Abstract 4362363: Recent Trends and Outcomes of Mechanical Complications of Acute Myocardial Infarction

Background: Mechanical complications (MC) of acute myocardial infarction (AMI) [papillary muscle rupture (PMR), ventricular septal rupture (VSR), and ventricular free wall rupture (FWR)] have historically carried high morbidity and mortality. With the advent of early reperfusion therapies, their incidence has declined to less than 0.1% among AMI patients. However, limited data exists regarding outcomes of these serious complications in recent years. In this study, we evaluated recent trends and outcomes associated with MC in AMI. Methods: The National Inpatient Sample database from 2018 to 2022 was used, and regression analysis was performed. Results: AMI was the primary diagnosis in 2.9 million, of whom 1,255 (0.04%) developed MC: 540 (43%) PMR, 40 (3%) VSR, and 680 (54%) FWR. Patients with MC were older (70.1 vs 66.6 years, p<0.001), more often female (43% vs 36%, p=0.02) and white (81% vs 73%, p=0.01), but had similar Charlson Comorbidity Index ≥3 compared to those without (54% vs 52%, p=0.56). Multivariable logistic regression identified age and diabetes as independent predictors of mortality in patients with MC (p<0.05 for both). Adjusted analysis showed higher in-hospital mortality (57% vs 5%), longer length of stay (7 vs 4 days), and higher total cost of hospitalization ($259,564 vs $113,945) in those with MC (p<0.001 for all). Other in-hospital adverse outcomes were also noted more frequently in those with MC [Table]. In subgroup analysis, early PCI (<24 hours) was associated with lower odds of MC in STEMI patients {adjusted odds ratio(aOR) = 0.49 [95% confidence interval (CI)] = 0.35-0.67, p<0.001}, but not in NSTEMI (aOR = 0.48, 95% CI = 0.17-1.4, p=0.18). In AMI patients with MC, early PCI was not associated with lower in-hospital mortality regardless of the type of AMI (STEMI or NSTEMI). There was no significant trend noted in the prevalence of MC over the study period using a regression model (p=0.74). Conclusion: This study demonstrates that MC are more prevalent in older white women. Although MC is relatively rare, it is associated with significantly increased in-hospital morbidity, mortality, length of stay, and hospitalization costs. There was a lower incidence of MC in AMI patients treated with early PCI, but the timing of PCI did not affect in-hospital mortality.