Prophylaxis with diltiazem decreases arrhythmia rate when compared to beta-blocker following lobectomy.

Background: There is mixed evidence supporting arrhythmia prophylaxis after lobectomy in patients not taking preoperative beta-blockers (BBs). We sought to determine the safety and efficacy of postoperative-BB versus diltiazem in BB-naïve patients in preventing post-lobectomy arrhythmia. Methods: This was a cohort study at one academic medical center (01/2019-03/2023). All patients undergoing elective lobectomy were included. Before May 2021, all patients undergoing lobectomy received low dose oral metoprolol postoperatively for arrhythmia prophylaxis. After May 2021, patients were started on oral diltiazem postoperatively unless they were receiving BB preoperatively, in which case their BB was continued. Patients were divided into pre-implementation versus post-implementation groups. The primary outcome was the rate of postoperative arrhythmia; secondary outcomes were the rates of postoperative heart failure, nonhome discharge, stroke and hypotension. Bivariable and multivariable logistic regression comparisons were performed. Results: In total, 606 patients were included; 318 patients (52.5%) were in the pre-implementation cohort. There were minimal differences in perioperative characteristics between groups. Patients in the post-implementation cohort had significantly lower rates of postoperative cardiac arrhythmias (5.2% Conclusions: Patients had lower risk-adjusted rates of post-lobectomy arrhythmia and hypotension when using diltiazem for arrhythmia prevention compared to metoprolol. Our findings support the use of postoperative diltiazem preferentially in BB-naïve patients.