Abstract
Abnormal (<50%) ejection fraction (EF) is a cornerstone of risk stratification and therapy, but also an imperfect proxy of left ventricular (LV) cardiac pump function, better assessed with stroke volume (SV).
To assess the value of SV in stratifying risk of patients with abnormal EF.
In a prospective, observational, multicenter study, we recruited 746 patients (age 66± 11 years, 536 males, 72%, 359 with previous myocardial infarction, 48%) with chronic coronary syndromes (CCS) and EF <50% referred for resting transthoracic echocardiography with technically successful 2-dimensional volumetric echocardiography in 17 accredited laboratories. We quantitatively assessed LV end-diastolic volume (EDV) and end-systolic volume (ESV) by Simpson’s biplane method. EF (EDV-ESV/EDV) and SV (EDV-ESV) were calculated from LV volumes. The outcome end-point was all-cause death.
EF was 39±9%, SV 48±20 ml. There were 100 all-cause deaths during a median follow-up of 796 days (interquartile range 420-1286 days). Receiver-operating curve analysis identified SV≤31.4 ml/b as the best cut-off for predicting mortality. At multivariable analysis, after adjustment for age and prior myocardial infarction, EF <40% and SV ≤31.4 ml/b were significantly associated with decreased survival (HR 2.09, 95%, confidence intervals 1.09-4.01, p=0.024). The annual mortality was lowest (3.19%) in the group with mildly reduced (40-49%) EF and normal (>31.4 ml) SV, and highest (8.30%) in patients with both reduced EF and abnormal SV: see figure.
Figure
Author notes
Funding Acknowledgements: None.
