Mechanical circulatory support with microaxial flow pump for high-risk PCI: a comparative analysis in left main disease

Background High-risk percutaneous coronary interventions (HR-PCI) are increasingly common, and mechanical circulatory support (MCS) has emerged as a potential adjunct to improve patient outcomes. However, data comparing MCS to standard care remain limited. This study evaluates the impact of microaxial flow pump (m-AFP)-supported HR-PCI in left main (LM) disease on achievement of complete revascularization and on mortality at follow-up. Methods The standard-of-care (SOC) cohort was derived from the Delta (Drug Eluting Stent for Left Main Coronary Artery) 2 Registry and included all patients with distal LM bifurcation disease and left ventricular ejection fraction (LVEF) <40%. The m-AFP population was extracted from the IMP-IT (IMPella Mechanical Circulatory Support Device in Italy) Registry and comprised patients with severe LM stenosis who underwent HR-PCI with m-AFP support. Baseline characteristics were compared to assess key differences between the two populations. The primary endpoint was complete revascularization, defined as treatment of all identified diseased vessels. Mortality was assessed at follow-up using Kaplan-Meier analysis. Results A total of 414 patients were included in the analysis (332 form the Delta 2 and 82 from the IMP-IT Registry). Baseline characteristics such as age, body mass index, hypertension, dyslipidemia and diabetes were comparable between the two cohorts. Baseline creatinine and LVEF did not differ (1.38±1.5 vs 1.63±1.7mg/dl and 32.3±11.4 vs 32.3±7%). SOC patients had more frequently suffered from myocardial infarction (36.5 vs 52.7%, p=0.009). Upon coronary angiography, the rate of three-vessel disease was higher among the m-AFP patients (71.6 vs 34.0%, p<0.001). Despite a higher burden of coronary artery disease, patients in the m-AFP cohort were more likely to achieve complete revascularization, and this association remained significant after adjusting for prior MI (45.6% vs. 23.9%, OR 2.71, 95% CI 1.62–4.55, p<0.001). At a comparable median follow-up, the m-AFP cohort showed a numerical trend toward lower mortality (15.4% vs. 25.3%, HR 1.70, 95% CI 0.93–3.13, p=0.087). Conclusions In HR-PCI for LM disease, m-AFP support was associated with a higher likelihood of achieving complete revascularization. A numerical trend towards lower mortality was also observed.