A Retrospective Review of Cardiogenic Shock Development in Patients With ST-Elevation Myocardial Infarction and Percutaneous Coronary Intervention Receiving Early Beta-Blockers.

Abstract

Beta-blockers (BBs) have proven to improve morbidity and mortality in patients after an ST elevation myocardial infarction (STEMI). Guidelines suggest initiating a BB within 24 hours, except in those with risk factors for developing cardiogenic shock, although published literature is conflicting regarding the true association of these risk factors with shock. This retrospective cohort study aimed to assess whether the presence of defined risk factors was associated with cardiogenic shock after early BB administration in patients with a STEMI and percutaneous coronary intervention. The primary outcome determined the rate of cardiogenic shock development and secondarily determined any characteristics associated with cardiogenic shock in patients who received beta blockers. The population included 299 patients and cardiogenic shock occurred in 8 patients (2.7%). There were no median (interquartile range) differences in age [63 years (60-71) versus 62 years (52-71); P = 0.4965], systolic blood pressure [110 mm Hg (105-115) versus 109 mm Hg (103-114); P = 0.6027], or heart rate [90 (78-104) versus 76 (64-90); P = 0.0697] before BB administration in patients who developed shock versus those who did not, respectively. Hours to BB administration from arrival [15.6 (6.0-54.8) versus 21.9 (10.6-42; P = 0.6968] and the number (%) with anterior infarction [3 (37.5%) versus 107 (36.8%); P = 1.000] were similar between groups. There was a statistically significant higher median (interquartile range) peak troponin [140 ng/mL (54-304) versus 49 ng/mL (16-132); P = 0.0354] in patients who developed shock. Early initiation of a BB in patients with STEMI and percutaneous coronary intervention with risk factors for cardiogenic shock does not seem to be associated with shock in most patients.