Variability in reporting of key outcome predictors in acute myocardial infarction cardiogenic shock trials

Background: Among acute myocardial infarction patients with cardiogenic shock (AMICS), a number of key variables predict mortality, including cardiac arrest (CA) and shock classification as proposed by Society for Cardiovascular Angiography and Intervention (SCAI). Given this prognostic importance, we examined the frequency of reporting of high risk variables in published randomized controlled trials (RCTs) of AMICS patients.

Methods: We identified 15 RCTs enrolling 2,500 AMICS patients and then reviewed rates of CA, baseline neurologic status, right heart catheterization data, lactate levels, inotrope and vasopressor requirement, hypothermia, mechanical ventilation, left ventricular ejection fraction (LVEF), mechanical circulatory support, and specific cause of death based on the primary manuscript and Data in S1.

Results: A total of 2,500 AMICS patients have been enrolled in 15 clinical trials over 21 years with only four trials enrolling >80 patients. The reporting frequency and range for key prognostic factors was: neurologic status (0% reported), hypothermia (28% reported, prevalence 33-75%), specific cause of death (33% reported), cardiac index and wedge pressure (47% reported, range 1.6-2.3 L min^-1 m^-2 and 15-24 mmHg), lactate (60% reported, range 4-7.7 mmol/L), LVEF (73% reported, range 25-45%), CA (80% reported, prevalence 0-92%), MCS (80% reported, prevalence 13-100%), and mechanical ventilation (93% reported, prevalence 35-100%). This variability was reflected in the 30-day mortality which ranged from 20-73%.

Conclusions: In a comprehensive review of seminal RCTs in AMICS, important predictors of outcome were frequently not reported. Future efforts to standardize CS trial data collection and reporting may allow for better assessment of novel therapies for AMICS.