Characteristics and Outcomes of Early vs Late Initiation of Mechanical Circulatory Support in Non-Acute Myocardial Infarction related Cardiogenic Shock: An Analysis of the National Inpatient Sample Database

Cardiogenic shock (CS) is significant cause of mortality. The use of mechanical circulatory support (MCS) in patients with non-acute myocardial infarction (Non-AMI) CS is lacking. We inquired data regarding the trends and outcomes early vs late initiation of MCS in non-AMI CS. We investigated National Inpatient Sample database between October 2015-December 2018, identifying hospitalizations with CS, either complicated by AMI or Non-AMI. Patients were divided into 2 cohorts, early initiation of MCS (<48 hours) and late initiation of MCS (>48 hours). The primary analysis included death within first 24 hours. A secondary analysis was adjusted after excluding patients who died in first 24 hours. A total of 85,318 patients with non-AMI-related CS with MCS placement were identified. Among this cohort, 54.6% (n=46,579) underwent early initiation of MCS within 48 hours, and 45.4% (n=38,739) underwent late initiation of MCS after 48 hours. In primary analysis, early MCS initiation was associated with more in-hospital mortality in primary outcome of all-cause hospital mortality (35.72% vs 27.63%, P<0.0001, OR 1.44, 95% CI: 1.40-1.49, P<0.0001), however, adjusted secondary analysis showed a statistically significant decrease in all-cause hospital mortality (23.63% vs 27.63%, P<0.0001, OR 0.80, 95% CI: 0.78-0.83, P<0.0001). In non-AMI-related CS and based on survival to 24 hours after admission, early initiation of MCS had statistically significant decrease in all-cause hospital mortality, with less incidence of vascular and renal complications, and shorter hospital stay. Late initiation of MCS was associated with a higher incidence of advanced therapies, including LVAD and transplant.