Transition from classical to chimney Commando procedure: improved operative efficiency and zero permanent pacemaker in the chimney cohort – a single-surgeon experience

Background The Commando procedure (double valve replacement with annular enlargement) is technically challenging and associated with a high pacemaker rate. The chimney modification may simplify the operation. This study compared early outcomes between classical and chimney Commando performed by a single surgeon. Methods We retrospectively analysed 58 consecutive Commando procedures performed by a single surgeon (15 classical, 43 chimney). Early outcomes including operative times, 30-day mortality, permanent pacemaker implantation, and predischarge echocardiography were compared. Results Most baseline characteristics were similar, although concomitant tricuspid procedures were more frequent in the chimney group (51% vs 13%, p=0.014) and mitral valve size differed (27 vs 29 mm, p=0.002); active endocarditis (21% vs 6.7%) and atrial fibrillation (56% vs 33%) were also numerically more common. Chimney significantly reduced aortic cross-clamp time (96 [83, 116] vs 138 [104, 152] min, p=0.009) and cardiopulmonary bypass time (164 [148, 184] vs 215 [163, 235] min, p=0.019). No patient in the chimney group required a permanent pacemaker (0/43), compared with 6.7% (1/15) in the classical group (p=0.3). Thirty-day mortality was comparable (13.3% vs 11.6%, p>0.9). Predischarge aortic valve mean gradients and left ventricular ejection fraction were similar. No moderate or severe paravalvular leak occurred. Conclusions In this single-surgeon cohort, the chimney Commando procedure was associated with significantly shorter operative times and a zero pacemaker rate. These findings suggest that the chimney modification is a safe and efficient alternative to the classical technique, but they require validation in larger, multicentre studies. Trial registration Not applicable (retrospective observational study).