Right Ventricular Function After Acute Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention (from the Glycometabolic Intervention as Adjunct to Primary Percutaneous Coronary Intervention in ST-Segment Elevation Myocardial Infarction III Trial)

Abstract

Right ventricular (RV) dysfunction is a powerful risk marker after acute myocardial infarction (MI). Primary percutaneous coronary intervention (PCI) has markedly reduced myocardial damage of the left ventricle, but reliable data on RV damage using cardiac magnetic resonance imaging (MRI) are scarce. In a recent trial of patients with acute MI treated with primary PCI, in which the primary end point was left ventricular (LV) ejection fraction after 4months measured with MRI, we conducted a prospectively defined substudy in which we examined RV function. RV ejection fraction (RVEF) and RV scar size were measured with MRI at 4months. Tricuspid annular plane systolic excursion (TAPSE) and RV free wall longitudinal strain (FWLS) were assessed using echocardiography before discharge and at 4months. We studied 258 patients without diabetes mellitus; their mean age was 58 ± 11years, 79% men and mean LV ejection fraction was 54 ± 8%. Before discharge, 5.2% of patients had TAPSE <17mm, 32% had FWLS >-20% and 11% had FWLS >-15%. During 4months, TAPSE increased from 22.8 ± 3.6 to 25.1 ± 3.9mm (p <0.001) and FWLS increased from-22.6 ± 5.8 to-25.9 ± 4.7% (p <0.001). After 4months, mean RVEF on MRI was 64.1 ± 5.2% and RV scar was detected in 5 patients (2%). There was no correlation between LV scar size and RVEF (p= 0.9), TAPSE (p= 0.1), or RV FWLS (p=0.9). In conclusion, RV dysfunction is reversible in most patients and permanent RVischemic injury is very uncommon 4months after acute MI treated with primary PCI.