Outcome in Elderly Patients With Cardiogenic Shock Complicating Acute Myocardial Infarction

INTRODUCTION: Despite advances in treatment of patients with cardiogenic shock following acute myocardial infarction (AMICS) in-hospital mortality remains around 50%. Outcome varies among patient subsets and the elderly often have a poor a priori prognosis. We sought to investigate outcome among elderly AMICS patients referred to evaluation and treatment at a tertiary university hospital. METHODS: Current analysis was based on the RETROSHOCK registry comprising consecutive AMICS patients admitted to tertiary care. Patients in the registry were individually identified and validated. RESULTS: Of 1,716 admitted patients, 496 (28.9%) patients were ≥75 years old. Older patients were less likely to be admitted directly to a tertiary centre (59.4% vs. 69.9%, P = 0.003), receive mechanical support devices (i.e., Impella® (8.9% vs. 15.0%, P = 0.003), and undergo revascularization attempt (76.8% vs. 90.2%, P < 0.001). Thirty-day survivors ≥75 years were characterized by having higher left ventricular ejection fraction (30.2% ± 12.5% vs. 26.5% ± 11.8%, P = 0.004) and lower arterial lactate (3.2[2.2-5.2] mmol/L vs. 5.5[3.3-8.2] mmol/L, P < 0.001) at admission. In a multivariable analysis of patients ≥75 years, higher age (HR 1.09, 95% CI 1.05-1.14, P < 0.001), higher heart rate (HR 1.01, 95% CI 1.001-1.014, P = 0.03), and higher lactate (HR 1.11, 95% CI 1.07-1.16, P < 0.001) at admission were associated with an increased risk of 30-day mortality. CONCLUSION: Among patients ≥75 years with AMICS referred for tertiary specialized treatment, 30-day mortality was 73.4%. Survivors were characterized by lower arterial lactate and heart rate at admission.