Impact of Age in Acute Myocardial Infarction Cardiogenic Shock: Insights From the National Cardiogenic Shock Initiative

Abstract

Background: Acute myocardial infarction complicated by cardiogenic shock (AMICS) is associated with high mortality. Patients ≥75 years old represent an increasing proportion of those who present with AMICS and are at high risk for adverse outcomes. Methods: The National Cardiogenic Shock Initiative includes patients with AMICS treated using a standard shock protocol with early invasive hemodynamic monitoring, mechanical circulatory support (MCS), and percutaneous coronary intervention (PCI). We evaluated the outcomes of patients based on their age group, dividing them into <75 and ≥75 years old. Results: We included 300 consecutive patients: 238 were <75 years old (79.3%) and 62 patients ≥75 years old. There were significant differences in survival; patients <75 years old had a 75.6% survival, while those ≥75 years old had a 50% survival (adjusted OR: 10.4, P = 0.001). SCAI shock classification impacted survival as well; those <75 years old with class C or D shock had a survival of 84%, compared with 57% in those ≥75 years old. Patients ≥75 years old requiring 1 or 2 vasopressors had significantly lower survival rates (36% and 25%, respectively) when compared with patients <75 years old (76.7% with 1 and 60.5% with >1 vasopressor). Conclusions: Age is inversely proportional to survival; patients <75 years old have high rates of survival if treated using best practices with invasive hemodynamic monitoring, early MCS, and PCI. However, using a standardized protocol can improve survival in the elderly; therefore, age on its own should not be a reason to withhold PCI or MCS use.