Mechanical complications in STEMI: prevalence and mortality trends in the primary PCI era. The Ruti-STEMI registry

Introduction and objectives: Mechanical complications confer a dreadful prognosis in ST-elevation myocardial infarction (STEMI). Their prevalence and prognosis are not well-defined in the current era of primary percutaneous coronary intervention (pPCI) reperfusion networks. We aimed to analyze prevalence and mortality trends of post-STEMI mechanical complications over 2 decades, before and after the establishment of pPCI networks.

Methods: Prospective, consecutive registry of STEMI patients within a region of 850 000 inhabitants over 2 decades: a pre-pPCI period (1990-2000) and a pPCI period (2007-2017). We analyzed the prevalence of mechanical complications, including ventricular septal rupture, papillary muscle rupture, and free wall rupture (FWR). Twenty eight-day and 1-year mortality trends were compared between the 2 studied decades.

Results: A total of 6033 STEMI patients were included (pre-pPCI period, n=2250; pPCI period, n=3783). Reperfusion was supported by thrombolysis in the pre-pPCI period (99.1%) and by pPCI in in the pPCI period (95.7%). Mechanical complications developed in 135 patients (2.2%): ventricular septal rupture in 38 patients, papillary muscle rupture in 24, and FWR in 73 patients. FWR showed a relative reduction of 60% in the pPCI period (0.8% vs 2.0%, P<.001), without significant interperiod changes in the other mechanical complications. After multivariate adjustment, FWR remained higher in the pre-pPCI period (OR, 1.93; 95%CI, 1.10-3.41; P=.023). At 28 days and 1 year, mortality showed no significant changes in all the mechanical complications studied.

Conclusions: The establishment of regional pPCI networks has modified the landscape of mechanical complications in STEMI. FWR is less frequent in the pPCI era, likely due to reduced transmural infarcts.