Reply to Patel and Hunt

We appreciate Patel and Hunt's interest in our study and their comments regarding this [1, 2].

In the last decades, focus has shifted from mortality to more interest on morbidity in surgical procedures. If morbidity is reduced, the risk of mortality will expectedly follow.

Postoperative atrial fibrillation occurs in 5–65% of patients undergoing surgery for lung cancer and is therefore a main contributor to morbidity [3].

The magnitude of risk not only depends on the definition of atrial fibrillation, but also on the type of surgery, use of antiarrhythmic medication and follow-up time.

Although postoperative atrial fibrillation is often regarded as a temporary, benign, operation-related problem, it is associated with a 2- to 3-fold increase of adverse events, including transient or permanent stroke, acute myocardial infarction and death [3].

Reduced diastolic filling of the left ventricle due to unstructured contractions in the left atrium reduces cardiac output by 20–30%, resulting in a worse short- and long-term prognosis after lung surgery [4].

An increase in length of stay in the intensive care unit and prolonged total hospital stay—with increased costs—has also been reported [2].

The observed incidence of atrial fibrillation following lung surgery has increased over the last 20 years, which may be due to advanced patient age, more extensive surgery and an increased focus on atrial fibrillation [5].

There have been several attempts to reduce the risk of atrial fibrillation and, to date, amiodarone has proved to be the most efficient medical prophylactic agent [3]. We agree with Patel and Hunt that studies have shown similar results regarding calcium blockers [1]. Nevertheless, calcium blockers have an increased risk of bradycardia and hypotension compared with placebo and amiodarone.

Regarding cost analysis, the prophylactic regime mentioned and suggested by Patel and Hunt [1] was based on a non-randomized population where a single surgeon admitted 600 mg amiodarone per day, whereas other surgeons did not. Accordingly, the study is severely biased, and conclusions must be drawn with caution. Furthermore, different strategies in patient care postoperatively in different hospital settings alter cost–benefit analyses, and hence a general cost–benefit strategy in prophylactic amiodarone is difficult to determine. We fully agree with the comments regarding Patel and Hunt [1]. However, studies from cardiac surgery suggest that an efficient and cost–benefit prophylactic regime could consist of ∼1–2 g of amiodarone a day for 5 days starting on the first postoperative day [6]. We also agree that a tailored prophylactic regime would be an optimal way to administer prophylactic drugs in regard to safety, minimizing medicine given and reduce hospital cost. So far, the preoperative detection of high-risk patients is though not consistent and hence further studies into this area are warranted.

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