Current US prevalence of myocardial injury patterns and clinical outcomes among hospitalised patients with familial hypercholesterolaemia: insight from the National Inpatient Sample—a retrospective cohort study

Abstract

Background Familial hypercholesterolaemia (FH) increases propensity for premature atherosclerotic disease. Knowledge of inpatient outcomes among patients with FH admitted with acute myocardial injury (AMI) is limited.Objectives Our study aimed to identify myocardial injury types, including type 1 myocardial infarction (MI), type 2 MI and takotsubo cardiomyopathy, assess lesion severity and study adverse short-term inpatient outcomes among patients with FH admitted with AMI.Setting Our study retrospectively queried the US National Inpatient Sample from 2018 to 2020.Population Adults admitted with AMI and dichotomised based on the presence of FH.Study outcomes We evaluated myocardial injury types and complexity of coronary revascularisation. Primary outcome of all-cause mortality and other clinical secondary outcomes were studied.Results There were 3 711 765 admissions with AMI including 2360 (0.06%) with FH. FH was associated with higher odds of ST-elevation MI (STEMI) (adjusted OR (aOR): 1.62, p<0.001) and non-ST-elevation MI (NSTEMI) (aOR: 1.29, p<0.001) but lower type 2 MI (aOR: 0.39, p<0.001) and takotsubo cardiomyopathy (aOR: 0.36, p=0.004). FH was associated with higher multistent percutaneous coronary interventions (aOR: 2.36, p<0.001), multivessel coronary artery bypass (aOR: 2.65, p<0.001), higher odds of intracardiac thrombus (aOR: 3.28, p=0.038) and mechanical circulatory support (aOR: 1.79, p<0.001). There was 50% reduction in odds of all-cause mortality (aOR: 0.50, p=0.006) and lower odds of mechanical ventilation (aOR: 0.37, p<0.001). There was no difference in rate of ventricular tachycardia, cardioversion, new implantable cardioverter defibrillator implantation, cardiogenic shock and cardiac arrest.Conclusion Among patients hospitalised with AMI, FH was associated with higher STEMI and NSTEMI, lower type 2 MI and takotsubo cardiomyopathy, higher number of multiple stents and coronary bypasses, and mechanical circulatory support device but was associated with lower all-cause mortality and rate of mechanical ventilation.