Is minimally invasive mitral valve surgery equal to or worse than a full sternotomy: a perspective from the Netherlands National Heart Registration

Abstract

New surgical techniques and strategies need scientific analysis and evaluation of sufficiently large patient cohorts with respect to equality, possible superiority or even inferiority compared to established therapies. Because randomized trials may not be feasible in some instances for various reasons, single-centre patient populations, sometimes merged with multicentre databases, are studied. With the inherent limitations of single- and multicentre studies, excluding data from centres not adept with a specific treatment, the truth about the effectiveness of a new therapy is valid only for a fraction of the total population. So it appears obvious to use national registries that by definition include all patients in a certain country. Olsthoorn et al. [1] have analysed data from the Netherlands Heart Registration of 2501 patients who had mitral valve surgery either alone or combined with tricuspid valve surgery, atrial fibrillation ablation or ASD closure for differences in short- and long-term outcomes between minimally invasive, i.e. minithoracotomy [minimally invasive mitral valve surgery (MIMVS)] or full sternotomy approaches. After propensity matching for baseline characteristics and concomitant procedures, surgical and long-term results with respect to mortality were excellent and comparable in both cohorts, but patients who underwent MIMVS had a lower repair rate (76.3% vs 80.9%) and a slight, but significantly lower freedom from reintervention at 5 years (96.8% vs 97.9%). Interestingly, the total length of the hospital stay was longer in patients who had MIMVS.