Comparing outcomes in cardiogenic shock patients with ischemic versus nonischemic cardiomyopathy: A nationwide retrospective observational study

Abstract Introduction Ischemic and non-ischemic cardiomyopathy are common causes of heart failure. In our study, we compare the in-hospital outcomes between these two groups of patients with cardiogenic shock. Methods Data was obtained from the Nationwide Inpatient Sample database between January 2016 to December 2020. The study included all adult patients who were in cardiogenic shock and either ischemic cardiomyopathy (ICM) or non-ischemic cardiomyopathy (NICM). The primary outcome was inpatient mortality. Secondary outcomes were cardiac arrest, arrhythmias, acute respiratory failure, and acute renal failure, as well as the need for ventilators, dialysis, and ECMO. Results Among 168,591 adult patients who had cardiogenic shock during their hospitalization, 72,538 patients had either ischemic cardiomyopathy or nonischemic cardiomyopathy. Among them, 31,854 (43.9%) had ischemic cardiomyopathy (ICM) vs 40,684 (56.1%) who had nonischemic cardiomyopathy (NICM). Patients with NICM had higher in-patient mortality (24.6% vs 26.1, aOR: 1.12; 95% CI: 1.08-1.16, p<0.001); when adjusted for age, sex, race, and Charlson comorbidity index. Furthermore, patients with NICM also had a higher risk of respiratory failure (54.1% vs 53.8%, aOR:1.11, 95% CI: 1.07-1.14, p<0.001) and required more life-saving treatments like pressors (1.6% vs 0.7%, aOR: 1.14; 95% CI: 1.10-1.20, p< 0.001) and dialysis (12.7.1% vs 11.3%, aOR:1.20, 95% CI: 1.14-1.26, p<0.001). However, these patients with NICM had a lower risk of cardiac arrest (7.2% vs 7.8%, aOR: 0.88; 95% CI: 0.84-0.94, p< 0.001) and ventricular arrhythmias (29.5% vs 32.2%, aOR: 0.82; 95% CI: 0.80-0.86, p<0.001) as well as lower ECMO utilization (2.5 vs 2.1, aOR:0.82; 95% CI: 0.73-0.92, p <0.001) and blood transfusions (9.8% vs 11.7%, aOR:0.839; 95% CI: 0.80-0.88, p< 0.001). There was no significant difference in the ventilator use between the 2 groups (40.3% vs 39.7%, aOR:1.01, 95% CI: 0.97-1.04, p=0.714). Conclusion The findings of this study underscore the higher in-patient mortality among patients with non-ischemic cardiomyopathy (NICM) presenting with cardiogenic shock. These results emphasize the need for tailored treatment approaches targeting NICM-CS, warranting dedicated diagnostic and therapeutic strategies to improve prognosis in this vulnerable patient subset.Odd's ratios for NICM-CS vs ICM-CS