Impact of right ventricular dysfunction assessed by cardiac magnetic resonance imaging on prediction of short term and long term prognoses after acute inferior myocardial infarction

Method We analyzed 20 consecutive patients (14 male; age 64 ± 12 years) with first acute inferior MI due to proximal right coronary lesion. All patients were assessed with cardiac MRI after primary percutaneous coronary intervention and followed up for a median (25, 75 percentiles) of 6 (5, 6) months. We assessed the association of RV function with length of cardiac care unit (CCU) treatment as an index of short-term prognosis by using multiple regression analysis, and used Kaplan-Meier analysis to demonstrate the association of RV dysfunction with occurrence of heart failure (HF) after discharge as an index of long-term prognosis. Results RV involvement was diagnosed with delayed enhancement MRI in 11 patients (55%). Patients with RV involvement had lower RV ejection fraction (EF) (32.4 ± 8.6 % vs 43.2 ± 7.7 %; p = 0.009) and longer duration of CCU treatment (5.3 ± 2.3 days vs 3.5 ± 1.9 days; p = 0.038) than those without RV involvement, although there were no significant differences regarding clinical, angiographic and the other MRI characteristics such as left ventricular parameters. By multiple regression analysis, RVEF was an independent predictor of length of CCU treatment (standardized partial regression coefficient -0.799, partial regression coefficient -0.127; 95% confidence interval -0.222 to -0.031; p = 0.017). KaplanMeier analysis demonstrated that RVEF <30% was associated with increased occurrence of HF in chronic phase (p = 0.003).