Abstract 16130: Right Ventricular Dysfunction After Acute Myocardial Infarction in the Absence of Pulmonary Hypertension
Background. Cardiac remodelling after AMI is characterized by molecular and cellular mechanisms involving both the ischemic and non-ischemic myocardium. The extent of right ventricular (RV) dilatation and dysfunction and its relation to pulmonary hypertension (PH) following AMI are unknown. The aim of the current study was to evaluate changes in dimensions and function of the RV following acute myocardial infarction (AMI) involving the left ventricle (LV).
Methods. We assessed changes in RV dimensions and function in 10 patients with ST-segment elevation AMI sparing the RV and without pre-existing PH undergoing paired cardiac magnetic resonance and echocardiographic Doppler imaging studies at study entry (within 48 hours of hospital admission) and 3 months following STEMI.
Results. In patients with STEMI, RV ejection fraction or RV tricuspidal annulus tissue Doppler velocity declined by 17% (P=0.007) and 18% (P=0.024), respectively. Pulmonary artery systolic pressure estimated at Doppler remained within the normal values and unchanged following AMI. The percent reduction in RVEF was directly correlated with infarct size (R=+0.66, P=0.038). Final RVEF and final LVEF were significantly correlated with each other (R=+0.86, P=0.001), suggesting an interaction between LV and RV function. The changes in RVEF occurred independent of infarct location, culprit coronary artery, the presence of multivessel disease, type of stent, or use of pharmacotherapy (aspirin, beta-adrenergic receptor blockers, angiotensin converting enzyme inhibitors, or statins).
Conclusion. AMI involving the LV and sparing the RV induces a significant acute decline in RV systolic function in the absence of pulmonary hypertension indicating that RV dysfunction developed independent of changes in RV afterload.
- © 2011 by American Heart Association, Inc.