https://orcid.org/0000-0001-8372-4132
Abstract
To assess changes in the results of septal myectomy (SM) following introduction of three-dimensional (3D) imaging and 3D printing in surgical interventions planning and performing in the single-centre settings.
Between January 2007 and March 2022, 268 consecutive symptomatic patients with hypertrophic obstructive cardiomyopathy and peak pressure gradient at obstruction area ≥50 mmHg underwent conventional SM (n = 112) or SM with heart 3D modelling (n = 156).
For comparative analysis, we used propensity score matching (PSM) by 14 variables and there were formed group 1PSM (conventional SM, n = 77) and group 2PSM (3D-modelled SM, n = 77). It was noted for group 2PSM: larger mean resected myocardium mass [10.0 (standard deviation 4.3) vs 5.2 (standard deviation 2.7) g], P < 0.001, no mitral valve replacement cases [0 vs 28 (36.4%), P < 0.001], no iatrogenic ventricular septal defects cases [0 vs 6 (7.8%), P = 0.028], lower rate of major complications [6 (7.8%) vs 17 (22.1%), P = 0.011], smaller residual peak systolic gradient at the obstruction level [7.0 (5.0–9.0) vs 11.0 (7.0–16.0) mmHg, P < 0.001]. During the long-term follow-up, it was noted for group 2PSM as compared to group 1PSM: lower 5-year cumulative incidence of major adverse cardiovascular events [3.8% (95% confidence interval 0.7–11.7%) vs 16.9% (9.5–26.1%), P = 0.007] and cardiac-related death [3.8% (95% confidence interval 0.7–11.7%) vs 13% (95% confidence interval 6.6–21.6%), P = 0.05].
SM based on 3D virtual and printed heart models is more effective than conventional SM.
INTRODUCTION
The 1st and foremost utilization of three-dimensional (3D) imaging and printing in surgery lies in planning and performing of high-risk complex procedures that leave little margin for an error. Clinical experience with this technology is limited despite encouraging results in cardiac surgery [1, 2]. In hypertrophic obstructive cardiomyopathy (HOCM) surgical treatment, 3D-printed models proved to be a useful tool in personalized preoperative planning and assessment [3–6]. Performing septal myectomy (SM) based on high-quality imaging data rather than subjective assessment helps to achieve the most durable intraoperative results and improve long-term patient outcomes [7, 8]. Long-term follow-up showed that adequate SM induces remodelling of the entire left ventricle (LV) [9, 10].
However, there were no studies aimed at objective comparison of in-hospital and long-term outcomes of conventional SM and SM based on personalized 3D virtual and printed heart models. This precluded from recommending the latter approach as an advanced first-line method of choice in HOCM surgical management.
MATERIALS AND METHODS
Ethical statement
The study was approved by the Local ethics committee (No 12/19, December 2016).
Patients, examination, surgical planning and surgery
This was a single-centre retrospective study. Two-hundred and sixty-eight consecutive patients with HOCM symptoms were admitted for conventional SM (n = 112, group 1, January 2007 to July 2020) or for SM based on 3D virtual and printed heart models (n = 156, group 2, January 2017 to March 2022), according to the previously described protocol [4, 7, 10, 11]. Since 2017, the 3D-modelled SM method has become our standard and has not been used only in case of technical issues. The inclusion criterion was a peak LV pressure gradient at ≥50 mmHg at rest or with exercise—for cases with latent obstruction. The exclusion criteria were contraindications to surgical treatment.
In both groups, preoperative examinations included transthoracic echocardiography (TTE) and additionally in group 2—computed tomography angiography (Siemens SOMATOM Force, Siemens Healthcare AG, Erlangen, Germany) or cardiovascular magnetic resonance (Siemens MAGNETOM Aera 1.5 T) [7, 12]. Transoesophageal echocardiography was performed before and after cardiopulmonary bypass during surgery.
In group 2, we built virtual 3D models of interventricular septum (IVS) and LV abnormal muscle bundles (Fig. 1A) using the InVesalius (https://invesalius.github.io/) open source software and Autodesk Meshmixer (https://meshmixer.com) software, based on cardiovascular magnetic resonance data in 52 patients (33.3%) and computed tomography angiography data in 104 patients (66.7%). We performed computer mapping [7, 11] of the IVS with 3D model cross-cutting in different planes with taking measurements of IVS and abnormal muscle bundles (Fig. 1B). Following this analysis, we performed a virtual SM aiming at producing an IVS close to ideal with resulting maximum thickness of 10–13 mm. IVS model and resected fragment were 3D-printed in polylactide using a 3D printer with low production costs (FlashForge Guider 3D printer; FlashForge Corp., Zhejiang, China). It takes 10–18 h to get a printed 3D model from imaging to the surgeon.
(A) 3D models of the interventricular septum with abnormal muscle bundles after virtual septal myectomy. (B) 3D models of the interventricular septum for septal myectomy planning, first surgeon view. 3D: three-dimensional; IVS: interventricular septum; LCA: left coronary artery; LVOT: left ventricular outflow tract; RCA: right coronary artery; VSM: virtual septal myectomy.
In group 1, conventional SM surgery was done via the ascending aorta according to classic guidelines [13]. In group 2, SM was performed as per description in our previous publications [4, 7, 10]. We used needles inserted into the 3D model for precise visualization of resected myocardium layer during myectomy. Sterilized 3D model was taken to the operating theatre. Removed myocardium was put in layers on the 3D model until tips of the needles were reached. Once myectomy was completed, excised myocardium was weighed (Fig. 2).
Surgery steps: (A) using 3D-printed model in measuring myocardial resection depth and width and (B) weighing of resected myocardium. 3D: three-dimensional.
Surgical interventions were performed by 5 surgeons. The surgeon who performed most of the 3D-modelled SM cases had an experience of 13 SM surgeries before 2017, 7 of which resulted in mitral valve (MV) replacement. One more surgeon was involved in performing 3D-modelled SM operations. He had no previous experience in performing SM, and his learning curve started with 3D-modelled SM approach. These 2 surgeons together performed 98% of 3D-modelled SM cases.
Complications, 30-day mortality and follow-up
Clavien–Dindo classification (grades IIIb–V) was used for the assessment of 30-day mortality and major hospital complications. During follow-up, patients were reviewed for clinical symptoms, along with electrocardiography and TTE. Checkpoints for the follow-up were d: discharge, 3 months, and then every 12 months after the surgery until April 2022. Major adverse cardiovascular events (MACE) are defined as a composite of nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death.
Statistical analysis
IBM SPSS Statistics software (v. 20.0; IBM Corp., Armonk, NY, USA) was used for the purpose of statistics calculations. For comparative analysis, we utilized method of propensity score matching (PSM) [14] incorporating «psmatching» software into IBM SPSS Statistics with ratio matching 1:1, calliper 0.2, and calculation of standardized mean difference. We used Kolmogorov–Smirnov test for continuous variables with normal distribution, which were presented as mean and standard deviation. Student’s t test was utilized for comparison of the above-mentioned values. Two-sided Pearson’s χ2-test and Fisher’s exact test were used to compare categorical variables, which were reported as number and percentage. Mann–Whitney U-test was used to compare continuous variables with asymmetric distribution, which were reported as median and 25th and 75th percentiles. For paired comparison between group 1PSM and group 2PSM, paired t-test, McNemar’s test and signed-rank test were used. Kaplan–Meier method was used for the follow-up and survival analysis (mean and 95% confidence interval, CI). The comparison of TTE data, functional class of heart failure New York Heart Association (NYHA) and all events was done using time-dependent methods including Gray’s test. A statistical hypothesis of equal distributions was rejected at P ≤ 0.05.
RESULTS
For comparative analysis, we used method of PSM [14] by 14 variables: gender, age, body mass index, functional class of heart failure NYHA, risk of cardiac surgery, organic changes in the aortic and MVs, peak gradient in the left ventricular outflow tract and at the mid-segments of LV, degree of mitral regurgitation, LV ejection fraction, maximum thickness of IVS, degree of MV systolic anterior motion and LV end-diastolic volume. There were formed group 1PSM (n = 77) and group 2PSM (n = 77), based on cardiovascular magnetic resonance data in 33 patients (42.9%) and computed tomography angiography data in 44 patients (57.1%). Table 1 summarizes patients’ data before surgery. There was no difference between 2 groups in any of the parameters, except slightly higher systolic pulmonary artery pressure in group 1PSM: 35.0 (30.0–38.5) vs 29.0 (25.0–36.5) mmHg, P = 0.002. Table 2 demonstrates patients’ main perioperative characteristics.
Baseline clinical characteristics and transthoracic echocardiography data before surgery
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P value | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P-value | ||
|---|---|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||||
| Male gender | 42 (54.5%) | 40 (51.9%) | 0.09 | 0.44 | 60 (53.6%) | 83 (53.2%) | –0.16 | 1.0 |
| Age (years) | 54.3 (12.0) | 54.8 (11.0) | 0.004 | 0.80 | 53 (43–61) | 54 (47–63) | 0.29 | 0.13 |
| Body surface area (m2) (SD) | 1.94 (0.2) | 1.97 (0.19) | 0.07 | 0.41 | 1.92 (0.21) | 1.95 (0.17) | –0.19 | 0.05 |
| FC NYHA I | 1 (1.3%) | 1 (1.3%) | 0.92 | 1 (0.9%) | 7 (4.5%) | 0.15 | ||
| FC NYHA II | 32 (42%) | 31 (40.3%) | 0.90 | 33 (29.5%) | 90 (57.7%) | <0.001 | ||
| FC NYHA III | 43 (55.8%) | 44 (57.1%) | 0.91 | 73 (65.2%) | 58 (37.2%) | <0.001 | ||
| FC NYHA IV | 1 (1.3%) | 1 (1.3%) | 0.92 | 5 (4.5%) | 1 (0.64%) | 0.09 | ||
| FC NYHA, mean | 3.0 (2.0–3.0) | 3.0 (2.0–3.0) | 0.09 | 0.91 | 2.7 (0.55) | 2.3 (0.57) | 0.71 | <0.001 |
| EuroSCORE 2 | 1.6 (1.0–2.2) | 1.5 (1.0–2.9) | 0.05 | 0.40 | 1.4 (1.0–2.5) | 1,3 (0.9–2.2) | 0.18 | 0.23 |
| Peak LVOT systolic gradient (mmHg) | 76.1 (22.3) | 72.9 (28.9) | –0.2 | 0.44 | 74 (62–90) | 70 (50–85.3) | –0.07 | 0.006 |
| Peak systolic gradient at midventricular segments (mmHg) | 3.0 (2.0–6.5) | 3.0 (3.0–6.5) | 0.1 | 0.41 | 4.0 (2.0–8.0) | 5.0 (3.0–11.0) | –0.01 | 0.37 |
| Maximum IVS thickness (mm) | 21.2 (2.9) | 21.2 (3.2) | –0.15 | 0.99 | 21 (19–23) | 21 (18.4–22) | –0.17 | 0.09 |
| LVEDV (ml) (SD) | 112.5 (32.9) | 113.9 (32.0) | 0.06 | 0.78 | 109.4 (33.8) | 111.2 (31.5) | –0.24 | 0.67 |
| LVESV (ml) (SD) | 39.4 (15.9) | 40.9 (15.1) | 0.55 | 38.5 (15.9) | 39.1 (14.8) | 0.77 | ||
| LVEF (Simpson, %) | 64.9 (7.4) | 64.1 (7.1) | –0.14 | 0.50 | 66 (60.3–70) | 65 (59–71) | 0.04 | 0.98 |
| SAM | 75 (97.4%) | 77 (100%) | –0.07 | 0.98 | 110 (98,2%) | 150 (96,2%) | –0.19 | 0.52 |
| No SAM | 2 (2.6%) | 0 | 0.48 | 2 (1.8%) | 6 (3.8%) | 0.32 | ||
| Grade 1/3 | 1 (1.3%) | 4 (5.2%) | 0.36 | 1 (0.9%) | 6 (3.8%) | 0.25 | ||
| Grade 2/3–3/3 | 74 (96.1%) | 73 (94.8%) | 0.70 | 109 (97,3) | 144 (92,3) | 0,12 | ||
| Mitral regurgitation: mean | 3.0 (2.5–3.5) | 3.0 (2.5–3.5) | –0.11 | 0.80 | 3 (2.5–4) | 3 (2.5–3) | 0.16 | <0.001 |
| Mild (1/4) | 2 (2.6%) | 2 (2.6%) | 1.0 | 2 (1.8%) | 7 (4.5%) | 0.31 | ||
| Moderate (2/4) | 22 (28.6%) | 21(27.3%) | 0.86 | 27 (24.1%) | 52 (33.3%) | 0.13 | ||
| Moderately severe (3/4) | 38 (49.3%) | 38 (49.3%) | 1.0 | 52 (46.4%) | 72 (46.2%) | 0.01 | ||
| Severe (4/4) | 15 (19.5%) | 16 (20.8%) | 0.84 | 31 (27.7%) | 19 (12.2%) | 0.003 | ||
| Tricuspid regurgitation, mean | 1.5 (1.5–2.0) | 1.5 (1.0–2.0) | 0.79 | 36,2 (10.7) | 29,4 (10.0) | <0.001 | ||
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P value | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P-value | ||
|---|---|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||||
| Male gender | 42 (54.5%) | 40 (51.9%) | 0.09 | 0.44 | 60 (53.6%) | 83 (53.2%) | –0.16 | 1.0 |
| Age (years) | 54.3 (12.0) | 54.8 (11.0) | 0.004 | 0.80 | 53 (43–61) | 54 (47–63) | 0.29 | 0.13 |
| Body surface area (m2) (SD) | 1.94 (0.2) | 1.97 (0.19) | 0.07 | 0.41 | 1.92 (0.21) | 1.95 (0.17) | –0.19 | 0.05 |
| FC NYHA I | 1 (1.3%) | 1 (1.3%) | 0.92 | 1 (0.9%) | 7 (4.5%) | 0.15 | ||
| FC NYHA II | 32 (42%) | 31 (40.3%) | 0.90 | 33 (29.5%) | 90 (57.7%) | <0.001 | ||
| FC NYHA III | 43 (55.8%) | 44 (57.1%) | 0.91 | 73 (65.2%) | 58 (37.2%) | <0.001 | ||
| FC NYHA IV | 1 (1.3%) | 1 (1.3%) | 0.92 | 5 (4.5%) | 1 (0.64%) | 0.09 | ||
| FC NYHA, mean | 3.0 (2.0–3.0) | 3.0 (2.0–3.0) | 0.09 | 0.91 | 2.7 (0.55) | 2.3 (0.57) | 0.71 | <0.001 |
| EuroSCORE 2 | 1.6 (1.0–2.2) | 1.5 (1.0–2.9) | 0.05 | 0.40 | 1.4 (1.0–2.5) | 1,3 (0.9–2.2) | 0.18 | 0.23 |
| Peak LVOT systolic gradient (mmHg) | 76.1 (22.3) | 72.9 (28.9) | –0.2 | 0.44 | 74 (62–90) | 70 (50–85.3) | –0.07 | 0.006 |
| Peak systolic gradient at midventricular segments (mmHg) | 3.0 (2.0–6.5) | 3.0 (3.0–6.5) | 0.1 | 0.41 | 4.0 (2.0–8.0) | 5.0 (3.0–11.0) | –0.01 | 0.37 |
| Maximum IVS thickness (mm) | 21.2 (2.9) | 21.2 (3.2) | –0.15 | 0.99 | 21 (19–23) | 21 (18.4–22) | –0.17 | 0.09 |
| LVEDV (ml) (SD) | 112.5 (32.9) | 113.9 (32.0) | 0.06 | 0.78 | 109.4 (33.8) | 111.2 (31.5) | –0.24 | 0.67 |
| LVESV (ml) (SD) | 39.4 (15.9) | 40.9 (15.1) | 0.55 | 38.5 (15.9) | 39.1 (14.8) | 0.77 | ||
| LVEF (Simpson, %) | 64.9 (7.4) | 64.1 (7.1) | –0.14 | 0.50 | 66 (60.3–70) | 65 (59–71) | 0.04 | 0.98 |
| SAM | 75 (97.4%) | 77 (100%) | –0.07 | 0.98 | 110 (98,2%) | 150 (96,2%) | –0.19 | 0.52 |
| No SAM | 2 (2.6%) | 0 | 0.48 | 2 (1.8%) | 6 (3.8%) | 0.32 | ||
| Grade 1/3 | 1 (1.3%) | 4 (5.2%) | 0.36 | 1 (0.9%) | 6 (3.8%) | 0.25 | ||
| Grade 2/3–3/3 | 74 (96.1%) | 73 (94.8%) | 0.70 | 109 (97,3) | 144 (92,3) | 0,12 | ||
| Mitral regurgitation: mean | 3.0 (2.5–3.5) | 3.0 (2.5–3.5) | –0.11 | 0.80 | 3 (2.5–4) | 3 (2.5–3) | 0.16 | <0.001 |
| Mild (1/4) | 2 (2.6%) | 2 (2.6%) | 1.0 | 2 (1.8%) | 7 (4.5%) | 0.31 | ||
| Moderate (2/4) | 22 (28.6%) | 21(27.3%) | 0.86 | 27 (24.1%) | 52 (33.3%) | 0.13 | ||
| Moderately severe (3/4) | 38 (49.3%) | 38 (49.3%) | 1.0 | 52 (46.4%) | 72 (46.2%) | 0.01 | ||
| Severe (4/4) | 15 (19.5%) | 16 (20.8%) | 0.84 | 31 (27.7%) | 19 (12.2%) | 0.003 | ||
| Tricuspid regurgitation, mean | 1.5 (1.5–2.0) | 1.5 (1.0–2.0) | 0.79 | 36,2 (10.7) | 29,4 (10.0) | <0.001 | ||
EuroSCORE 2: European System for Cardiac Operative Risk Evaluation; FC: functional class; IVS: interventricular septum; LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; LVOT: left ventricular outflow tract; NYHA: New York Heart Association; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; SMD: standardized mean difference.
Baseline clinical characteristics and transthoracic echocardiography data before surgery
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P value | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P-value | ||
|---|---|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||||
| Male gender | 42 (54.5%) | 40 (51.9%) | 0.09 | 0.44 | 60 (53.6%) | 83 (53.2%) | –0.16 | 1.0 |
| Age (years) | 54.3 (12.0) | 54.8 (11.0) | 0.004 | 0.80 | 53 (43–61) | 54 (47–63) | 0.29 | 0.13 |
| Body surface area (m2) (SD) | 1.94 (0.2) | 1.97 (0.19) | 0.07 | 0.41 | 1.92 (0.21) | 1.95 (0.17) | –0.19 | 0.05 |
| FC NYHA I | 1 (1.3%) | 1 (1.3%) | 0.92 | 1 (0.9%) | 7 (4.5%) | 0.15 | ||
| FC NYHA II | 32 (42%) | 31 (40.3%) | 0.90 | 33 (29.5%) | 90 (57.7%) | <0.001 | ||
| FC NYHA III | 43 (55.8%) | 44 (57.1%) | 0.91 | 73 (65.2%) | 58 (37.2%) | <0.001 | ||
| FC NYHA IV | 1 (1.3%) | 1 (1.3%) | 0.92 | 5 (4.5%) | 1 (0.64%) | 0.09 | ||
| FC NYHA, mean | 3.0 (2.0–3.0) | 3.0 (2.0–3.0) | 0.09 | 0.91 | 2.7 (0.55) | 2.3 (0.57) | 0.71 | <0.001 |
| EuroSCORE 2 | 1.6 (1.0–2.2) | 1.5 (1.0–2.9) | 0.05 | 0.40 | 1.4 (1.0–2.5) | 1,3 (0.9–2.2) | 0.18 | 0.23 |
| Peak LVOT systolic gradient (mmHg) | 76.1 (22.3) | 72.9 (28.9) | –0.2 | 0.44 | 74 (62–90) | 70 (50–85.3) | –0.07 | 0.006 |
| Peak systolic gradient at midventricular segments (mmHg) | 3.0 (2.0–6.5) | 3.0 (3.0–6.5) | 0.1 | 0.41 | 4.0 (2.0–8.0) | 5.0 (3.0–11.0) | –0.01 | 0.37 |
| Maximum IVS thickness (mm) | 21.2 (2.9) | 21.2 (3.2) | –0.15 | 0.99 | 21 (19–23) | 21 (18.4–22) | –0.17 | 0.09 |
| LVEDV (ml) (SD) | 112.5 (32.9) | 113.9 (32.0) | 0.06 | 0.78 | 109.4 (33.8) | 111.2 (31.5) | –0.24 | 0.67 |
| LVESV (ml) (SD) | 39.4 (15.9) | 40.9 (15.1) | 0.55 | 38.5 (15.9) | 39.1 (14.8) | 0.77 | ||
| LVEF (Simpson, %) | 64.9 (7.4) | 64.1 (7.1) | –0.14 | 0.50 | 66 (60.3–70) | 65 (59–71) | 0.04 | 0.98 |
| SAM | 75 (97.4%) | 77 (100%) | –0.07 | 0.98 | 110 (98,2%) | 150 (96,2%) | –0.19 | 0.52 |
| No SAM | 2 (2.6%) | 0 | 0.48 | 2 (1.8%) | 6 (3.8%) | 0.32 | ||
| Grade 1/3 | 1 (1.3%) | 4 (5.2%) | 0.36 | 1 (0.9%) | 6 (3.8%) | 0.25 | ||
| Grade 2/3–3/3 | 74 (96.1%) | 73 (94.8%) | 0.70 | 109 (97,3) | 144 (92,3) | 0,12 | ||
| Mitral regurgitation: mean | 3.0 (2.5–3.5) | 3.0 (2.5–3.5) | –0.11 | 0.80 | 3 (2.5–4) | 3 (2.5–3) | 0.16 | <0.001 |
| Mild (1/4) | 2 (2.6%) | 2 (2.6%) | 1.0 | 2 (1.8%) | 7 (4.5%) | 0.31 | ||
| Moderate (2/4) | 22 (28.6%) | 21(27.3%) | 0.86 | 27 (24.1%) | 52 (33.3%) | 0.13 | ||
| Moderately severe (3/4) | 38 (49.3%) | 38 (49.3%) | 1.0 | 52 (46.4%) | 72 (46.2%) | 0.01 | ||
| Severe (4/4) | 15 (19.5%) | 16 (20.8%) | 0.84 | 31 (27.7%) | 19 (12.2%) | 0.003 | ||
| Tricuspid regurgitation, mean | 1.5 (1.5–2.0) | 1.5 (1.0–2.0) | 0.79 | 36,2 (10.7) | 29,4 (10.0) | <0.001 | ||
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P value | Value, n (%), mean (SD) or median (25–75th percentile) | SMD | P-value | ||
|---|---|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||||
| Male gender | 42 (54.5%) | 40 (51.9%) | 0.09 | 0.44 | 60 (53.6%) | 83 (53.2%) | –0.16 | 1.0 |
| Age (years) | 54.3 (12.0) | 54.8 (11.0) | 0.004 | 0.80 | 53 (43–61) | 54 (47–63) | 0.29 | 0.13 |
| Body surface area (m2) (SD) | 1.94 (0.2) | 1.97 (0.19) | 0.07 | 0.41 | 1.92 (0.21) | 1.95 (0.17) | –0.19 | 0.05 |
| FC NYHA I | 1 (1.3%) | 1 (1.3%) | 0.92 | 1 (0.9%) | 7 (4.5%) | 0.15 | ||
| FC NYHA II | 32 (42%) | 31 (40.3%) | 0.90 | 33 (29.5%) | 90 (57.7%) | <0.001 | ||
| FC NYHA III | 43 (55.8%) | 44 (57.1%) | 0.91 | 73 (65.2%) | 58 (37.2%) | <0.001 | ||
| FC NYHA IV | 1 (1.3%) | 1 (1.3%) | 0.92 | 5 (4.5%) | 1 (0.64%) | 0.09 | ||
| FC NYHA, mean | 3.0 (2.0–3.0) | 3.0 (2.0–3.0) | 0.09 | 0.91 | 2.7 (0.55) | 2.3 (0.57) | 0.71 | <0.001 |
| EuroSCORE 2 | 1.6 (1.0–2.2) | 1.5 (1.0–2.9) | 0.05 | 0.40 | 1.4 (1.0–2.5) | 1,3 (0.9–2.2) | 0.18 | 0.23 |
| Peak LVOT systolic gradient (mmHg) | 76.1 (22.3) | 72.9 (28.9) | –0.2 | 0.44 | 74 (62–90) | 70 (50–85.3) | –0.07 | 0.006 |
| Peak systolic gradient at midventricular segments (mmHg) | 3.0 (2.0–6.5) | 3.0 (3.0–6.5) | 0.1 | 0.41 | 4.0 (2.0–8.0) | 5.0 (3.0–11.0) | –0.01 | 0.37 |
| Maximum IVS thickness (mm) | 21.2 (2.9) | 21.2 (3.2) | –0.15 | 0.99 | 21 (19–23) | 21 (18.4–22) | –0.17 | 0.09 |
| LVEDV (ml) (SD) | 112.5 (32.9) | 113.9 (32.0) | 0.06 | 0.78 | 109.4 (33.8) | 111.2 (31.5) | –0.24 | 0.67 |
| LVESV (ml) (SD) | 39.4 (15.9) | 40.9 (15.1) | 0.55 | 38.5 (15.9) | 39.1 (14.8) | 0.77 | ||
| LVEF (Simpson, %) | 64.9 (7.4) | 64.1 (7.1) | –0.14 | 0.50 | 66 (60.3–70) | 65 (59–71) | 0.04 | 0.98 |
| SAM | 75 (97.4%) | 77 (100%) | –0.07 | 0.98 | 110 (98,2%) | 150 (96,2%) | –0.19 | 0.52 |
| No SAM | 2 (2.6%) | 0 | 0.48 | 2 (1.8%) | 6 (3.8%) | 0.32 | ||
| Grade 1/3 | 1 (1.3%) | 4 (5.2%) | 0.36 | 1 (0.9%) | 6 (3.8%) | 0.25 | ||
| Grade 2/3–3/3 | 74 (96.1%) | 73 (94.8%) | 0.70 | 109 (97,3) | 144 (92,3) | 0,12 | ||
| Mitral regurgitation: mean | 3.0 (2.5–3.5) | 3.0 (2.5–3.5) | –0.11 | 0.80 | 3 (2.5–4) | 3 (2.5–3) | 0.16 | <0.001 |
| Mild (1/4) | 2 (2.6%) | 2 (2.6%) | 1.0 | 2 (1.8%) | 7 (4.5%) | 0.31 | ||
| Moderate (2/4) | 22 (28.6%) | 21(27.3%) | 0.86 | 27 (24.1%) | 52 (33.3%) | 0.13 | ||
| Moderately severe (3/4) | 38 (49.3%) | 38 (49.3%) | 1.0 | 52 (46.4%) | 72 (46.2%) | 0.01 | ||
| Severe (4/4) | 15 (19.5%) | 16 (20.8%) | 0.84 | 31 (27.7%) | 19 (12.2%) | 0.003 | ||
| Tricuspid regurgitation, mean | 1.5 (1.5–2.0) | 1.5 (1.0–2.0) | 0.79 | 36,2 (10.7) | 29,4 (10.0) | <0.001 | ||
EuroSCORE 2: European System for Cardiac Operative Risk Evaluation; FC: functional class; IVS: interventricular septum; LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; LVOT: left ventricular outflow tract; NYHA: New York Heart Association; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; SMD: standardized mean difference.
Main perioperative characteristics
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| AV replacement | 4 (5.2%) | 6 (7.8%) | 0.75 | 8 (7.1%) | 9 (5.8%) | 0.8 |
| Aorta replacement | 1 (1.3%) | 4 (5.2%) | 0.37 | 3 (2.7%) | 6 (3.8%) | 0.74 |
| CABG | 15 (19.5%) | 12 (15.6%) | 0.67 | 16 (14.3%) | 24 (15.4%) | 0.86 |
| MV replacement | 28 (36.4%) | 0 | <0.001 | 45 (40.2%) | 0 | <0.001 |
| Mechanical prosthesis | 23 (29.9%) | 0 | <0.001 | 38 (33.9%) | 0 | <0.001 |
| Biological prosthesis | 5 (6.5%) | 0 | 0.07 | 7 (6.3%) | 0 | <0.001 |
| Concomitant procedure, mean | 0 (0–1.0) | 1.0 (1.0–2.0) | <0.001 | 0 (0–1) | 1 (1–2) | <0.001 |
| Cross-clamp time (min) (SD) | 103.0 (41.1) | 119.4 (40.6) | 0.02 | 101 (68.3–136) | 112 (94–140) | 0.001 |
| Weight of resected muscle (g) (SD) | 5.2 (2.7), min 0.4, max 11.5 | 10.0 (4.3) min 4.1, max 32.6 | <0.001 | 5.1 (3.0), min 0.4, max 11.5 | 10 (4.4), min 4.1, max 32.6 | <0.001 |
| Iatrogenic VSD | 6 (7.8%) | 0 | 0.02 | 7 (6.3%) | 0 | <0.001 |
| Major perioperative complications, total | 17 (22.1%) | 6 (7.8%) | 0.011 | 21 (18.8%) | 13 (8.3%) | 0.015 |
| Postoperative ICU stay (days) | 1.0 (1.0–2.0) | 1.0 (1.0–1.0) | 0.036 | 1 (1–2) | 1 (1–1) | 0.004 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| AV replacement | 4 (5.2%) | 6 (7.8%) | 0.75 | 8 (7.1%) | 9 (5.8%) | 0.8 |
| Aorta replacement | 1 (1.3%) | 4 (5.2%) | 0.37 | 3 (2.7%) | 6 (3.8%) | 0.74 |
| CABG | 15 (19.5%) | 12 (15.6%) | 0.67 | 16 (14.3%) | 24 (15.4%) | 0.86 |
| MV replacement | 28 (36.4%) | 0 | <0.001 | 45 (40.2%) | 0 | <0.001 |
| Mechanical prosthesis | 23 (29.9%) | 0 | <0.001 | 38 (33.9%) | 0 | <0.001 |
| Biological prosthesis | 5 (6.5%) | 0 | 0.07 | 7 (6.3%) | 0 | <0.001 |
| Concomitant procedure, mean | 0 (0–1.0) | 1.0 (1.0–2.0) | <0.001 | 0 (0–1) | 1 (1–2) | <0.001 |
| Cross-clamp time (min) (SD) | 103.0 (41.1) | 119.4 (40.6) | 0.02 | 101 (68.3–136) | 112 (94–140) | 0.001 |
| Weight of resected muscle (g) (SD) | 5.2 (2.7), min 0.4, max 11.5 | 10.0 (4.3) min 4.1, max 32.6 | <0.001 | 5.1 (3.0), min 0.4, max 11.5 | 10 (4.4), min 4.1, max 32.6 | <0.001 |
| Iatrogenic VSD | 6 (7.8%) | 0 | 0.02 | 7 (6.3%) | 0 | <0.001 |
| Major perioperative complications, total | 17 (22.1%) | 6 (7.8%) | 0.011 | 21 (18.8%) | 13 (8.3%) | 0.015 |
| Postoperative ICU stay (days) | 1.0 (1.0–2.0) | 1.0 (1.0–1.0) | 0.036 | 1 (1–2) | 1 (1–1) | 0.004 |
AV: aortic valve; CABG: coronary aortic bypass grafting; ICU: intensive care unit; MV: mitral valve; PSM: propensity score matching; SD: standard deviation; VSD: ventricular septal defect.
Main perioperative characteristics
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| AV replacement | 4 (5.2%) | 6 (7.8%) | 0.75 | 8 (7.1%) | 9 (5.8%) | 0.8 |
| Aorta replacement | 1 (1.3%) | 4 (5.2%) | 0.37 | 3 (2.7%) | 6 (3.8%) | 0.74 |
| CABG | 15 (19.5%) | 12 (15.6%) | 0.67 | 16 (14.3%) | 24 (15.4%) | 0.86 |
| MV replacement | 28 (36.4%) | 0 | <0.001 | 45 (40.2%) | 0 | <0.001 |
| Mechanical prosthesis | 23 (29.9%) | 0 | <0.001 | 38 (33.9%) | 0 | <0.001 |
| Biological prosthesis | 5 (6.5%) | 0 | 0.07 | 7 (6.3%) | 0 | <0.001 |
| Concomitant procedure, mean | 0 (0–1.0) | 1.0 (1.0–2.0) | <0.001 | 0 (0–1) | 1 (1–2) | <0.001 |
| Cross-clamp time (min) (SD) | 103.0 (41.1) | 119.4 (40.6) | 0.02 | 101 (68.3–136) | 112 (94–140) | 0.001 |
| Weight of resected muscle (g) (SD) | 5.2 (2.7), min 0.4, max 11.5 | 10.0 (4.3) min 4.1, max 32.6 | <0.001 | 5.1 (3.0), min 0.4, max 11.5 | 10 (4.4), min 4.1, max 32.6 | <0.001 |
| Iatrogenic VSD | 6 (7.8%) | 0 | 0.02 | 7 (6.3%) | 0 | <0.001 |
| Major perioperative complications, total | 17 (22.1%) | 6 (7.8%) | 0.011 | 21 (18.8%) | 13 (8.3%) | 0.015 |
| Postoperative ICU stay (days) | 1.0 (1.0–2.0) | 1.0 (1.0–1.0) | 0.036 | 1 (1–2) | 1 (1–1) | 0.004 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| AV replacement | 4 (5.2%) | 6 (7.8%) | 0.75 | 8 (7.1%) | 9 (5.8%) | 0.8 |
| Aorta replacement | 1 (1.3%) | 4 (5.2%) | 0.37 | 3 (2.7%) | 6 (3.8%) | 0.74 |
| CABG | 15 (19.5%) | 12 (15.6%) | 0.67 | 16 (14.3%) | 24 (15.4%) | 0.86 |
| MV replacement | 28 (36.4%) | 0 | <0.001 | 45 (40.2%) | 0 | <0.001 |
| Mechanical prosthesis | 23 (29.9%) | 0 | <0.001 | 38 (33.9%) | 0 | <0.001 |
| Biological prosthesis | 5 (6.5%) | 0 | 0.07 | 7 (6.3%) | 0 | <0.001 |
| Concomitant procedure, mean | 0 (0–1.0) | 1.0 (1.0–2.0) | <0.001 | 0 (0–1) | 1 (1–2) | <0.001 |
| Cross-clamp time (min) (SD) | 103.0 (41.1) | 119.4 (40.6) | 0.02 | 101 (68.3–136) | 112 (94–140) | 0.001 |
| Weight of resected muscle (g) (SD) | 5.2 (2.7), min 0.4, max 11.5 | 10.0 (4.3) min 4.1, max 32.6 | <0.001 | 5.1 (3.0), min 0.4, max 11.5 | 10 (4.4), min 4.1, max 32.6 | <0.001 |
| Iatrogenic VSD | 6 (7.8%) | 0 | 0.02 | 7 (6.3%) | 0 | <0.001 |
| Major perioperative complications, total | 17 (22.1%) | 6 (7.8%) | 0.011 | 21 (18.8%) | 13 (8.3%) | 0.015 |
| Postoperative ICU stay (days) | 1.0 (1.0–2.0) | 1.0 (1.0–1.0) | 0.036 | 1 (1–2) | 1 (1–1) | 0.004 |
AV: aortic valve; CABG: coronary aortic bypass grafting; ICU: intensive care unit; MV: mitral valve; PSM: propensity score matching; SD: standard deviation; VSD: ventricular septal defect.
There was no statistical difference between group 1PSM and group 2PSM in the rate of the following postoperative outcomes: permanent pacemaker implantation—13 (16.9%) and 9 (11.7%), P = 0.5; cardioembolic complications—3 (3.9%) and 4 (5.2%), P = 1.0; atrial fibrillation paroxysms—16 (20.8%) and 26 (33.8%), P = 0.1; major non-cardiac complications—5 (6.5%) and 1 (1.3%), P = 0.2; 30-day mortality due to cardiac and non-cardiac causes—1 (1.3%) vs 0, P = 1.0 and 1 (1.3%) vs 0, P = 1.0; total 30-day mortality—2 (2.6%) vs 0, P = 0.5, accordingly.
Following isolated SM, it was noted lower rate of cardiopulmonary bypass restart in group 2PSM as compared to group 1PSM [8 (10.4%) vs 27 (35.0%), P < 0.001], mainly due to lower rate of severe mitral regurgitation [6 (7.8%) vs 18 (23.4%), P = 0.01]. There was no difference between the groups in total MV repair rate [10 (13.0%) for group 2PSM vs 17 (22.1%) for group 1PSM, P = 0.20]. Majority of MV repairs in group 1PSM were Carpentier ring annuloplasty—8 (10.4%) vs 0 in group 2PSM, P = 0.012.
In group 2PSM, there were no cases of MV replacement. The rate of reoperations was higher in group 1PSM [9 (11.7%) vs 2 (2.6%), P = 0.03].
There was no difference between group 1PSM and group 2PSM in the total rate of major cardiac complications excluding permanent pacemaker implantation [12 (15.6%) vs 5 (6.5%), P = 0.12]. There was a statistically significant difference in the rate of iatrogenic ventricular septal defect (VSD) between the groups with no such cases in group 2PSM [6 (7.8%) vs 0, P = 0.028].
In group 1PSM, 2 patients (2.6%) died within 30 days postoperatively: from progressive multiple organ failure due to bleeding and cardiac tamponade on day 27 and from haemorrhagic shock due to intestinal bleeding on day 23. In group 2PSM, there was no 30-day mortality.
Table 3 demonstrates comparison of TTE data between group 1PSM and group 2PSM in the early postoperative period.
Transthoracic echocardiography data in the early postoperative period
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| Residual peak systolic gradient at the obstruction level (mmHg), mean | 11.0 (7.0–16.0) | 7.0 (5.0–9.0) | <0.001 | 11 (7–18) | 6 (5–8) | <0.001 |
| LVEDV (ml) | 112.0 (31.4) | 124.3 (31.4) | 0.017 | 110 (81–132) | 120 (98.5–139) | 0.006 |
| LVESV (ml) (SD) | 45.1 (15.6) | 49.5 (18.5) | 0.11 | 44 (31.5–53.5) | 45 (38–59) | 0.078 |
| LVEF (Simpson, %) (SD) | 59.8 (7.4) | 61.0 (7.9) | 0.35 | 60 (55–66) | 59 (54–66) | 0.65 |
| SAM, Grade 2/3–3/3 | 2 (2.6%) | 0 | 0.48 | 3 (2.7) | 0 | 0.02 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 1.5 (1.0–2.0) | 0.11 | 1.5 (1.0–1.9) | 1.5 (1.0–2.0) | 0.013 |
| Moderately severe (3/4) | 2 (2.6%) | 1 (1.3%) | 1.0 | 2 (1.8%) | 1 (0.6%) | 0.94 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.0–2.0) | 1.5 (1.0–1.5) | 0.09 | 1.5 (1.0–2) | 1.5 (1.0–1.5) | <0.001 |
| sPAP (mmHg) | 32.3 (9.8) | 27.4 (7.9) | 0.001 | 32 (27–37) | 26 (21–31) | <0.001 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| Residual peak systolic gradient at the obstruction level (mmHg), mean | 11.0 (7.0–16.0) | 7.0 (5.0–9.0) | <0.001 | 11 (7–18) | 6 (5–8) | <0.001 |
| LVEDV (ml) | 112.0 (31.4) | 124.3 (31.4) | 0.017 | 110 (81–132) | 120 (98.5–139) | 0.006 |
| LVESV (ml) (SD) | 45.1 (15.6) | 49.5 (18.5) | 0.11 | 44 (31.5–53.5) | 45 (38–59) | 0.078 |
| LVEF (Simpson, %) (SD) | 59.8 (7.4) | 61.0 (7.9) | 0.35 | 60 (55–66) | 59 (54–66) | 0.65 |
| SAM, Grade 2/3–3/3 | 2 (2.6%) | 0 | 0.48 | 3 (2.7) | 0 | 0.02 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 1.5 (1.0–2.0) | 0.11 | 1.5 (1.0–1.9) | 1.5 (1.0–2.0) | 0.013 |
| Moderately severe (3/4) | 2 (2.6%) | 1 (1.3%) | 1.0 | 2 (1.8%) | 1 (0.6%) | 0.94 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.0–2.0) | 1.5 (1.0–1.5) | 0.09 | 1.5 (1.0–2) | 1.5 (1.0–1.5) | <0.001 |
| sPAP (mmHg) | 32.3 (9.8) | 27.4 (7.9) | 0.001 | 32 (27–37) | 26 (21–31) | <0.001 |
LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; sPAP: systolic pulmonary artery pressure.
Transthoracic echocardiography data in the early postoperative period
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| Residual peak systolic gradient at the obstruction level (mmHg), mean | 11.0 (7.0–16.0) | 7.0 (5.0–9.0) | <0.001 | 11 (7–18) | 6 (5–8) | <0.001 |
| LVEDV (ml) | 112.0 (31.4) | 124.3 (31.4) | 0.017 | 110 (81–132) | 120 (98.5–139) | 0.006 |
| LVESV (ml) (SD) | 45.1 (15.6) | 49.5 (18.5) | 0.11 | 44 (31.5–53.5) | 45 (38–59) | 0.078 |
| LVEF (Simpson, %) (SD) | 59.8 (7.4) | 61.0 (7.9) | 0.35 | 60 (55–66) | 59 (54–66) | 0.65 |
| SAM, Grade 2/3–3/3 | 2 (2.6%) | 0 | 0.48 | 3 (2.7) | 0 | 0.02 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 1.5 (1.0–2.0) | 0.11 | 1.5 (1.0–1.9) | 1.5 (1.0–2.0) | 0.013 |
| Moderately severe (3/4) | 2 (2.6%) | 1 (1.3%) | 1.0 | 2 (1.8%) | 1 (0.6%) | 0.94 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.0–2.0) | 1.5 (1.0–1.5) | 0.09 | 1.5 (1.0–2) | 1.5 (1.0–1.5) | <0.001 |
| sPAP (mmHg) | 32.3 (9.8) | 27.4 (7.9) | 0.001 | 32 (27–37) | 26 (21–31) | <0.001 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 77) | Group 2PSM (n = 77) | Group 1 (n = 112) | Group 2 (n = 156) | |||
| Residual peak systolic gradient at the obstruction level (mmHg), mean | 11.0 (7.0–16.0) | 7.0 (5.0–9.0) | <0.001 | 11 (7–18) | 6 (5–8) | <0.001 |
| LVEDV (ml) | 112.0 (31.4) | 124.3 (31.4) | 0.017 | 110 (81–132) | 120 (98.5–139) | 0.006 |
| LVESV (ml) (SD) | 45.1 (15.6) | 49.5 (18.5) | 0.11 | 44 (31.5–53.5) | 45 (38–59) | 0.078 |
| LVEF (Simpson, %) (SD) | 59.8 (7.4) | 61.0 (7.9) | 0.35 | 60 (55–66) | 59 (54–66) | 0.65 |
| SAM, Grade 2/3–3/3 | 2 (2.6%) | 0 | 0.48 | 3 (2.7) | 0 | 0.02 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 1.5 (1.0–2.0) | 0.11 | 1.5 (1.0–1.9) | 1.5 (1.0–2.0) | 0.013 |
| Moderately severe (3/4) | 2 (2.6%) | 1 (1.3%) | 1.0 | 2 (1.8%) | 1 (0.6%) | 0.94 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.0–2.0) | 1.5 (1.0–1.5) | 0.09 | 1.5 (1.0–2) | 1.5 (1.0–1.5) | <0.001 |
| sPAP (mmHg) | 32.3 (9.8) | 27.4 (7.9) | 0.001 | 32 (27–37) | 26 (21–31) | <0.001 |
LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; sPAP: systolic pulmonary artery pressure.
Follow-up
Long-term follow-up in group 1PSM was 7.6 years (standard deviation 3.7), in group 2PSM—3.2 years (standard deviation 1.2) (P < 0.001). TTE follow-up was completed in all patients discharged from the hospital: in group 1PSM—97.4% (75 of 77 patients), in group 2PSM—in 100% (77 of 77 patients) (Tables 4 and 5).
Transthoracic echocardiography data and FC NYHA at 2-year follow-up
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 44) | Group 2PSM (n = 37) | Group 1 (n = 53) | Group 2 (n = 63) | |||
| FC NYHA I | 28 (63.6%) | 20 (54.1%) | 0.3 | 35 (66.0%) | 36 (57.2%) | 0.45 |
| FC NYHA II | 13 (29.6%) | 13 (35.1%) | 0.61 | 16 (30.2%) | 21 (33.3%) | 0.78 |
| FC NYHA III | 3 (6.8%) | 4 (10.8%) | 0.70 | 2 (3.8%) | 6 (9.5%) | 0.34 |
| FC NYHA IV | 0 | 0 | 0.95 | 0 | 0 | 1.0 |
| FC NYHA, mean | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.57 | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.66 |
| Residual peak systolic gradient at the obstruction level (mmHg) | 7.0 (4.5–10.5) | 5.0 (4.0–7.0) | 0.13 | 7 (4–9) | 5 (4–7) | 0.19 |
| Maximum IVS thickness (mm) | 16.7 (3.6) | 13.5 (2.6) | <0.001 | 16 (14–18) | 13 (11–15) | <0.001 |
| LVEDV (ml) | 110.0 (84.5–135) | 114.5 (97–150) | 0.09 | 109 (84–134) | 121 (101.5–144) | 0.005 |
| LVESV (ml) | 39.0 (33.5–49.5) | 45.5 (41–60) | 0.05 | 38 (31–48) | 48 (42–61.5) | <0.001 |
| LVEF (Simpson, %) | 60.9 (6.7) | 58.5 (7.8) | 0.08 | 61.9 (7.1) | 58.5 (5.8) | 0.06 |
| SAM, Grade 2/3–3/3 | 1 (2.3%) | 0 | 0.41 | 5 (9.6%) | 0 | 0.03 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 2.0 (1.5–2.0) | 0.09 | 1.5 (1–2.0) | 1.5 (1.5–2.0) | 0.03 |
| Moderate (2/4) | 19 (43.2%) | 18 (48.6%) | 0.62 | 17 (32.1%) | 25 (39.7%) | 0.4 |
| Moderately severe (3/4) | 1 (2.3%) | 2 (5.4%) | 0.46 | 1 (1.9%) | 2 (3.2%) | 0.66 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.25–1.75) | 1.5 (1.0–1.5) | 0.7 | 1.5 (1–1.5) | 1.5 (1–1.5) | 0.79 |
| sPAP (mmHg) | 29.5 (25.5–33.5) | 18.5 (15.4–24) | <0.001 | 29 (24–33) | 17 (15–17) | <0.001 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 44) | Group 2PSM (n = 37) | Group 1 (n = 53) | Group 2 (n = 63) | |||
| FC NYHA I | 28 (63.6%) | 20 (54.1%) | 0.3 | 35 (66.0%) | 36 (57.2%) | 0.45 |
| FC NYHA II | 13 (29.6%) | 13 (35.1%) | 0.61 | 16 (30.2%) | 21 (33.3%) | 0.78 |
| FC NYHA III | 3 (6.8%) | 4 (10.8%) | 0.70 | 2 (3.8%) | 6 (9.5%) | 0.34 |
| FC NYHA IV | 0 | 0 | 0.95 | 0 | 0 | 1.0 |
| FC NYHA, mean | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.57 | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.66 |
| Residual peak systolic gradient at the obstruction level (mmHg) | 7.0 (4.5–10.5) | 5.0 (4.0–7.0) | 0.13 | 7 (4–9) | 5 (4–7) | 0.19 |
| Maximum IVS thickness (mm) | 16.7 (3.6) | 13.5 (2.6) | <0.001 | 16 (14–18) | 13 (11–15) | <0.001 |
| LVEDV (ml) | 110.0 (84.5–135) | 114.5 (97–150) | 0.09 | 109 (84–134) | 121 (101.5–144) | 0.005 |
| LVESV (ml) | 39.0 (33.5–49.5) | 45.5 (41–60) | 0.05 | 38 (31–48) | 48 (42–61.5) | <0.001 |
| LVEF (Simpson, %) | 60.9 (6.7) | 58.5 (7.8) | 0.08 | 61.9 (7.1) | 58.5 (5.8) | 0.06 |
| SAM, Grade 2/3–3/3 | 1 (2.3%) | 0 | 0.41 | 5 (9.6%) | 0 | 0.03 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 2.0 (1.5–2.0) | 0.09 | 1.5 (1–2.0) | 1.5 (1.5–2.0) | 0.03 |
| Moderate (2/4) | 19 (43.2%) | 18 (48.6%) | 0.62 | 17 (32.1%) | 25 (39.7%) | 0.4 |
| Moderately severe (3/4) | 1 (2.3%) | 2 (5.4%) | 0.46 | 1 (1.9%) | 2 (3.2%) | 0.66 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.25–1.75) | 1.5 (1.0–1.5) | 0.7 | 1.5 (1–1.5) | 1.5 (1–1.5) | 0.79 |
| sPAP (mmHg) | 29.5 (25.5–33.5) | 18.5 (15.4–24) | <0.001 | 29 (24–33) | 17 (15–17) | <0.001 |
FC: functional class; IVS: interventricular septum; LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; NYHA: New York Heart Association; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; sPAP: systolic pulmonary artery pressure.
Transthoracic echocardiography data and FC NYHA at 2-year follow-up
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 44) | Group 2PSM (n = 37) | Group 1 (n = 53) | Group 2 (n = 63) | |||
| FC NYHA I | 28 (63.6%) | 20 (54.1%) | 0.3 | 35 (66.0%) | 36 (57.2%) | 0.45 |
| FC NYHA II | 13 (29.6%) | 13 (35.1%) | 0.61 | 16 (30.2%) | 21 (33.3%) | 0.78 |
| FC NYHA III | 3 (6.8%) | 4 (10.8%) | 0.70 | 2 (3.8%) | 6 (9.5%) | 0.34 |
| FC NYHA IV | 0 | 0 | 0.95 | 0 | 0 | 1.0 |
| FC NYHA, mean | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.57 | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.66 |
| Residual peak systolic gradient at the obstruction level (mmHg) | 7.0 (4.5–10.5) | 5.0 (4.0–7.0) | 0.13 | 7 (4–9) | 5 (4–7) | 0.19 |
| Maximum IVS thickness (mm) | 16.7 (3.6) | 13.5 (2.6) | <0.001 | 16 (14–18) | 13 (11–15) | <0.001 |
| LVEDV (ml) | 110.0 (84.5–135) | 114.5 (97–150) | 0.09 | 109 (84–134) | 121 (101.5–144) | 0.005 |
| LVESV (ml) | 39.0 (33.5–49.5) | 45.5 (41–60) | 0.05 | 38 (31–48) | 48 (42–61.5) | <0.001 |
| LVEF (Simpson, %) | 60.9 (6.7) | 58.5 (7.8) | 0.08 | 61.9 (7.1) | 58.5 (5.8) | 0.06 |
| SAM, Grade 2/3–3/3 | 1 (2.3%) | 0 | 0.41 | 5 (9.6%) | 0 | 0.03 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 2.0 (1.5–2.0) | 0.09 | 1.5 (1–2.0) | 1.5 (1.5–2.0) | 0.03 |
| Moderate (2/4) | 19 (43.2%) | 18 (48.6%) | 0.62 | 17 (32.1%) | 25 (39.7%) | 0.4 |
| Moderately severe (3/4) | 1 (2.3%) | 2 (5.4%) | 0.46 | 1 (1.9%) | 2 (3.2%) | 0.66 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.25–1.75) | 1.5 (1.0–1.5) | 0.7 | 1.5 (1–1.5) | 1.5 (1–1.5) | 0.79 |
| sPAP (mmHg) | 29.5 (25.5–33.5) | 18.5 (15.4–24) | <0.001 | 29 (24–33) | 17 (15–17) | <0.001 |
| Variables | Value, n (%), mean (SD) or median (25–75th percentile) | P value | Value, n (%), mean (SD) or median (25–75th percentile) | P value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 44) | Group 2PSM (n = 37) | Group 1 (n = 53) | Group 2 (n = 63) | |||
| FC NYHA I | 28 (63.6%) | 20 (54.1%) | 0.3 | 35 (66.0%) | 36 (57.2%) | 0.45 |
| FC NYHA II | 13 (29.6%) | 13 (35.1%) | 0.61 | 16 (30.2%) | 21 (33.3%) | 0.78 |
| FC NYHA III | 3 (6.8%) | 4 (10.8%) | 0.70 | 2 (3.8%) | 6 (9.5%) | 0.34 |
| FC NYHA IV | 0 | 0 | 0.95 | 0 | 0 | 1.0 |
| FC NYHA, mean | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.57 | 1.0 (1.0–2.0) | 1.0 (1.0–2.0) | 0.66 |
| Residual peak systolic gradient at the obstruction level (mmHg) | 7.0 (4.5–10.5) | 5.0 (4.0–7.0) | 0.13 | 7 (4–9) | 5 (4–7) | 0.19 |
| Maximum IVS thickness (mm) | 16.7 (3.6) | 13.5 (2.6) | <0.001 | 16 (14–18) | 13 (11–15) | <0.001 |
| LVEDV (ml) | 110.0 (84.5–135) | 114.5 (97–150) | 0.09 | 109 (84–134) | 121 (101.5–144) | 0.005 |
| LVESV (ml) | 39.0 (33.5–49.5) | 45.5 (41–60) | 0.05 | 38 (31–48) | 48 (42–61.5) | <0.001 |
| LVEF (Simpson, %) | 60.9 (6.7) | 58.5 (7.8) | 0.08 | 61.9 (7.1) | 58.5 (5.8) | 0.06 |
| SAM, Grade 2/3–3/3 | 1 (2.3%) | 0 | 0.41 | 5 (9.6%) | 0 | 0.03 |
| Mitral regurgitation: mean | 1.5 (1.0–2.0) | 2.0 (1.5–2.0) | 0.09 | 1.5 (1–2.0) | 1.5 (1.5–2.0) | 0.03 |
| Moderate (2/4) | 19 (43.2%) | 18 (48.6%) | 0.62 | 17 (32.1%) | 25 (39.7%) | 0.4 |
| Moderately severe (3/4) | 1 (2.3%) | 2 (5.4%) | 0.46 | 1 (1.9%) | 2 (3.2%) | 0.66 |
| Severe (4/4) | 0 | 0 | 1.0 | 0 | 0 | 1.0 |
| Tricuspid regurgitation, mean | 1.5 (1.25–1.75) | 1.5 (1.0–1.5) | 0.7 | 1.5 (1–1.5) | 1.5 (1–1.5) | 0.79 |
| sPAP (mmHg) | 29.5 (25.5–33.5) | 18.5 (15.4–24) | <0.001 | 29 (24–33) | 17 (15–17) | <0.001 |
FC: functional class; IVS: interventricular septum; LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; NYHA: New York Heart Association; PSM: propensity score matching; SAM: systolic anterior motion; SD: standard deviation; sPAP: systolic pulmonary artery pressure.
5-year cumulative incidence of cardiac and noncardiac events at follow-up
| Variables | 5-year cumulative incidence, % (95% CI) | P-value | 5-year cumulative incidence, % (95% CI) | P-value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 75) | Group 2PSM (n = 77) | Group 1 (n = 110) | Group 2 (n = 156) | |||
| Prosthesis-associated complications, total | 16.9 (9.5–26.2) | 0 | <0.001 | 17 (10.7–24.6) | 0 | <0.001 |
| Mitral valve prostheses | 16.9 (9.5–26.2) | 0 | <0.001 | 16.1 (10.0–23.6) | 0 | <0.001 |
| Biological prostheses | 2.6 (0.5–8.2) | 0 | 0.157 | 1.8 (0.3–5.7) | 0 | 0.12 |
| Mechanical prostheses | 14.3 (7.6–23.2) | 0 | 0.003 | 15.2 (9.3–22.6) | 0 | <0.001 |
| Cardioembolic complications | 7.8 (3.2–15.2) | 0 | 0.046 | 6.3 (2.7–11.8) | 0 | 0.008 |
| PPM implantation | 2.6 (0.5–8.2) | 2.6 (0.5–8.3) | 1.00 | 2.7 (0.7–7.0) | 1.3 (0.3–4.3) | 0.59 |
| Malignancies | 2.6 (0.5–8.2) | 4.2 (1.1–10.9) | 0.66 | 1.8 (0.3–5.7) | 4.4 (1.8–8.9) | 0.29 |
| Sudden cardiac death | 6.5 (2.4–13.5) | 1.8 (0.1–8.6) | 0.32 | 5.4 (2.2–10.6) | 1.1 (0.1–5.3) | 0.13 |
| Cardiac cause of death | 13 (6.6–21.6) | 3.8 (0.7–11.7) | 0.05 | 11.6 (6.5–18.3) | 3.1 (0.8–8.3) | 0.019 |
| Non-cardiac cause of death | 7.8 (3.2–15.2) | 11.4 (3.6–24.2) | 0.74 | 6.3 (2.7–11.8) | 9.6 (3.7–19.0) | 0.55 |
| Variables | 5-year cumulative incidence, % (95% CI) | P-value | 5-year cumulative incidence, % (95% CI) | P-value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 75) | Group 2PSM (n = 77) | Group 1 (n = 110) | Group 2 (n = 156) | |||
| Prosthesis-associated complications, total | 16.9 (9.5–26.2) | 0 | <0.001 | 17 (10.7–24.6) | 0 | <0.001 |
| Mitral valve prostheses | 16.9 (9.5–26.2) | 0 | <0.001 | 16.1 (10.0–23.6) | 0 | <0.001 |
| Biological prostheses | 2.6 (0.5–8.2) | 0 | 0.157 | 1.8 (0.3–5.7) | 0 | 0.12 |
| Mechanical prostheses | 14.3 (7.6–23.2) | 0 | 0.003 | 15.2 (9.3–22.6) | 0 | <0.001 |
| Cardioembolic complications | 7.8 (3.2–15.2) | 0 | 0.046 | 6.3 (2.7–11.8) | 0 | 0.008 |
| PPM implantation | 2.6 (0.5–8.2) | 2.6 (0.5–8.3) | 1.00 | 2.7 (0.7–7.0) | 1.3 (0.3–4.3) | 0.59 |
| Malignancies | 2.6 (0.5–8.2) | 4.2 (1.1–10.9) | 0.66 | 1.8 (0.3–5.7) | 4.4 (1.8–8.9) | 0.29 |
| Sudden cardiac death | 6.5 (2.4–13.5) | 1.8 (0.1–8.6) | 0.32 | 5.4 (2.2–10.6) | 1.1 (0.1–5.3) | 0.13 |
| Cardiac cause of death | 13 (6.6–21.6) | 3.8 (0.7–11.7) | 0.05 | 11.6 (6.5–18.3) | 3.1 (0.8–8.3) | 0.019 |
| Non-cardiac cause of death | 7.8 (3.2–15.2) | 11.4 (3.6–24.2) | 0.74 | 6.3 (2.7–11.8) | 9.6 (3.7–19.0) | 0.55 |
CI: confidence interval; PSM: propensity score matching.
5-year cumulative incidence of cardiac and noncardiac events at follow-up
| Variables | 5-year cumulative incidence, % (95% CI) | P-value | 5-year cumulative incidence, % (95% CI) | P-value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 75) | Group 2PSM (n = 77) | Group 1 (n = 110) | Group 2 (n = 156) | |||
| Prosthesis-associated complications, total | 16.9 (9.5–26.2) | 0 | <0.001 | 17 (10.7–24.6) | 0 | <0.001 |
| Mitral valve prostheses | 16.9 (9.5–26.2) | 0 | <0.001 | 16.1 (10.0–23.6) | 0 | <0.001 |
| Biological prostheses | 2.6 (0.5–8.2) | 0 | 0.157 | 1.8 (0.3–5.7) | 0 | 0.12 |
| Mechanical prostheses | 14.3 (7.6–23.2) | 0 | 0.003 | 15.2 (9.3–22.6) | 0 | <0.001 |
| Cardioembolic complications | 7.8 (3.2–15.2) | 0 | 0.046 | 6.3 (2.7–11.8) | 0 | 0.008 |
| PPM implantation | 2.6 (0.5–8.2) | 2.6 (0.5–8.3) | 1.00 | 2.7 (0.7–7.0) | 1.3 (0.3–4.3) | 0.59 |
| Malignancies | 2.6 (0.5–8.2) | 4.2 (1.1–10.9) | 0.66 | 1.8 (0.3–5.7) | 4.4 (1.8–8.9) | 0.29 |
| Sudden cardiac death | 6.5 (2.4–13.5) | 1.8 (0.1–8.6) | 0.32 | 5.4 (2.2–10.6) | 1.1 (0.1–5.3) | 0.13 |
| Cardiac cause of death | 13 (6.6–21.6) | 3.8 (0.7–11.7) | 0.05 | 11.6 (6.5–18.3) | 3.1 (0.8–8.3) | 0.019 |
| Non-cardiac cause of death | 7.8 (3.2–15.2) | 11.4 (3.6–24.2) | 0.74 | 6.3 (2.7–11.8) | 9.6 (3.7–19.0) | 0.55 |
| Variables | 5-year cumulative incidence, % (95% CI) | P-value | 5-year cumulative incidence, % (95% CI) | P-value | ||
|---|---|---|---|---|---|---|
| Group 1PSM (n = 75) | Group 2PSM (n = 77) | Group 1 (n = 110) | Group 2 (n = 156) | |||
| Prosthesis-associated complications, total | 16.9 (9.5–26.2) | 0 | <0.001 | 17 (10.7–24.6) | 0 | <0.001 |
| Mitral valve prostheses | 16.9 (9.5–26.2) | 0 | <0.001 | 16.1 (10.0–23.6) | 0 | <0.001 |
| Biological prostheses | 2.6 (0.5–8.2) | 0 | 0.157 | 1.8 (0.3–5.7) | 0 | 0.12 |
| Mechanical prostheses | 14.3 (7.6–23.2) | 0 | 0.003 | 15.2 (9.3–22.6) | 0 | <0.001 |
| Cardioembolic complications | 7.8 (3.2–15.2) | 0 | 0.046 | 6.3 (2.7–11.8) | 0 | 0.008 |
| PPM implantation | 2.6 (0.5–8.2) | 2.6 (0.5–8.3) | 1.00 | 2.7 (0.7–7.0) | 1.3 (0.3–4.3) | 0.59 |
| Malignancies | 2.6 (0.5–8.2) | 4.2 (1.1–10.9) | 0.66 | 1.8 (0.3–5.7) | 4.4 (1.8–8.9) | 0.29 |
| Sudden cardiac death | 6.5 (2.4–13.5) | 1.8 (0.1–8.6) | 0.32 | 5.4 (2.2–10.6) | 1.1 (0.1–5.3) | 0.13 |
| Cardiac cause of death | 13 (6.6–21.6) | 3.8 (0.7–11.7) | 0.05 | 11.6 (6.5–18.3) | 3.1 (0.8–8.3) | 0.019 |
| Non-cardiac cause of death | 7.8 (3.2–15.2) | 11.4 (3.6–24.2) | 0.74 | 6.3 (2.7–11.8) | 9.6 (3.7–19.0) | 0.55 |
CI: confidence interval; PSM: propensity score matching.
Cumulative 5-year survival in group 1PSM and group 2PSM was 79.2% (95% CI 70.6–88.8%) and 84.8% (95% CI 74.2–96.9%), P = 0.108 (Log Rank test stratified by pairs); for group 1 and group 2, it was 79.2% (95% CI 75.3–89.5%) and 84.8% (95% CI 79.4–96%), respectively, P = 0.18 (Log Rank test).
Five-year cumulative incidence of heart failure progression (ejection fraction <45%) was 1.3% (95% CI 0.1–6.3%) and 2.8% (95% CI 0.5–8.7%) for groups 1PSM and 2PSM, respectively, P = 0.56.
Five-year cumulative incidence of aortic regurgitation progression (≥1 grade) in groups 1PSM and 2PSM was 10.4% (4.8–18.5%) and 7.6% (2.7–15.8%), respectively, P = 0.56.
Five-year cumulative incidence of cardiac surgeries and invasive procedures in group 1PSM (VSD repair, redo SM and 2 cases of MV replacement) vs group 2PSM (Amplatzer occluder delayed VSD closure, MV repair, pulmonary veins radiofrequency ablation, cardiac resynchronization therapy device implantation): 5.2% (1.7–11.9%) and 7.4% (2.7–15.4%), respectively, P = 0.41.
Five-year cumulative incidence of MACE was lower in group 2PSM—3.8% (95% CI 0.7–11.7%) vs 16.9% (9.5–26.1%), P = 0.007 and in group 2—3.2% (95% CI 0.8–8.5%) vs 15.2% (9.2–22.5%), P = 0.002.
In group 1PSM, 10 patients died due to cardiac causes: prosthetic endocarditis—1, progression of CHF—2, cardioembolic stroke—2, sudden cardiac death—4, myocardial infarction—1. Seven out of 10 deceased patients had mechanical MV prostheses, and in 4 patients, the cause of death were prosthesis-related complications; in another 2 patients with sudden cardiac death, prosthesis-related complications could have been a possible cause of death.
DISCUSSION
We have described previously the intragroup analysis of TTE data changes and results of surgical treatment in HOCM patients using 3D technologies [4, 7, 10].
To our knowledge, the present study is the 1st single-centre research aimed at PSM comparative analysis of HOCM surgical treatment results between conventional SM and SM using 3D imaging and printing.
We strongly believe that utilizing two-dimensional TTE as an assessment tool in HOCM surgery is associated with underestimation of maximum thickness and poor visualization of certain IVS segments. IVS 3D visualization is of a paramount importance for accurate assessment of LV obstruction anatomy and for SM planning [7, 10].
Study results showed that HOCM surgical treatment using 3D-modelled SM method was more radical than the conventional SM approach with larger resected myocardium mass, helped to avoid MV replacement provided no significant pre-existing structural valve changes and helped to avoid iatrogenic VSDs. It was associated with lower rate of cardiopulmonary bypass restarts, of reoperations in early postoperative period, of major complications and shorter stay in the intensive care unit. The method of 3D-modelled SM might shorten the learning curve as 2 surgeons who together performed 98% of 3D-modelled SM cases had limited or no previous experience in SM. Longer cross-clamp time in group 2PSM is explained by longer time required to perform more radical SM and larger number of concomitant procedures. More radical interventions in group 2 PSM were associated with a smaller residual peak systolic gradient at the obstruction level and more evident LV remodelling.
In the changed structure of early postoperative cardiac complications, 1st was paroxysmal atrial fibrillation followed by persistent complete AV-block and cardioembolic events.
The main reasons for long-term improvement of postoperative results in group 2PSM were more radical SM (confirmed by smaller resulting IVS thickness according to TTE data) and avoidance of MV replacement, which was proved to be a strong predictor of adverse events [15]. It was noted lower incidence of MACE, cardioembolic events and cardiac-related death, which was attributed mainly to the decrease in prosthesis-related complications rate. The tendency of higher grade of mitral regurgitation in group 2PSM postoperatively was not associated with severe clinical symptoms and is explained by implementing the strategy of native MV preservation provided no or moderate pre-existing structural valve changes and moderate degree of regurgitation.
We attribute progression of aortic valve insufficiency in the long-term postoperative period to prolonged traction of aortic valve ring during surgical intervention. Despite the low rate of this phenomenon, it also requires additional research and further improvements in surgical technique.
More radical SM was not associated with increase in 5-year cumulative incidence of heart failure progression; however, this requires further studies with larger number of cases.
To conclude, our study demonstrated improved early and long-term postoperative outcomes in HOCM patients with the use of 3D imaging and printing for SM planning and performing and identified new challenges in this area.
Limitations
Single-centre design of the study was a limitation. Conventional and 3D-modelled SM surgeries were performed during 2 discrete time periods, which could have had an indirect effect on study results. Matched patient’s cohort after PSM included 54% of total number of patients, which could have influenced representativeness of the results.
CONCLUSION
3D imaging and printing in SM planning and performing have radically improved its early and long-term results and changed structure of MACEs. Arrhythmias and cardioembolic complications were playing a key role in the changed pattern of perioperative complications. The recent profile of major long-term complications has included progression of mitral and aortic regurgitation, progression of heart failure and arrhythmias, rather than prosthesis-associated complications and relapses of LV obstruction.
FUNDING
None declared.
Conflict of interest: none declared.
DATA AVAILABILITY
Data will be available on request.
Author contributions
Uladzimir Andrushchuk: Conceptualization; Formal analysis; Methodology; Supervision; Writing—original draft. Artsem Niavyhlas: Formal analysis; Software; Visualization. Vitali Adzintsou: Data curation; Formal analysis; Writing—original draft. Dzmitry Tretsiakou: Data curation; Formal analysis; Visualization. Helena Zakharava: Data curation. Tatsjana Seuruk: Data curation; Visualization. Iraida Ustinava: Data curation; Visualization. Svetlana Kurganovich: Data curation; Visualization. Viktoryia Aleinikava: Data curation; Visualization. Mikalai Shchatsinka: Writing—original draft. Szymon Kocańda: Writing—original draft.
Reviewer information
Interactive CardioVascular and Thoracic Surgery thanks Nikolay O. Travin, Anton Tomsic, Hartzell V. Schaff and the other anonymous reviewers for their contribution to the peer review process of this article.
Presented at the Programme Committee for presentation at the 37th EACTS Annual Meeting, Vienna, Austria, 4–7 October 2023.
REFERENCES
ABBREVIATIONS
- 3D
Three-dimensional
- CI
Confidence interval
- HOCM
Hypertrophic obstructive cardiomyopathy
- IVS
Interventricular septum
- LV
Left ventricle
- MACE
Major adverse cardiovascular events
- MV
Mitral valve
- NYHA
New York Heart Association
- PSM
Propensity score matching
- SM
Septal myectomy
- TTE
Transthoracic echocardiography
- VSD
Ventricular septal defect
