Abstract 16192: Persistently Reduced Exercise Capacity After Cardiac Rehabilitation in Patients With Right Ventricular Infarction; Evidence of Impaired Right Ventricular Contribution
Background: It has been reported that exercise capacity is reduced in patients with right ventricular (RV) dysfunction but preserved left ventricular function early after acute myocardial infarction (AMI). However, it remains unknown whether exercise capacity is reduced in patients with “clinically diagnosed RV infarction” (RVI) than those with inferior AMI without RVI, and if so, whether or not the reduced exercise capacity in RVI patients persists even after cardiac rehabilitation with exercise training (CR/ET).
Methods and Results: To address these issues, we studied 356 consecutive inferior AMI patients who participated in CR/ET and underwent cardiopulmonary exercise test at the beginning and the end of the 3-month CR/ET program in our hospital. Patients were divided into RVI group (n=38) and Non-RVI (inferior AMI without RVI) group (n=318) according to the clinical diagnosis of RVI based on electrocardiographic, echocardiographic and hemodynamic criteria. At the beginning of CR/ET (approximately 3 weeks after AMI onset), RVI group showed significantly lower peak oxygen uptake (PVO2, RVI 71% vs Non-RVI 77%, p<0.05), but had higher peak CK (3826 vs 2220 U/L, p<0.001) than Non-RVI group, indicating a greater MI size in RVI than in Non-RVI patients. After paired matching in 1 to 2 ratio for age, sex, and peak CK in 37 RVI and 74 Non-RVI patients, peak CK (3931 vs 3848 U/L, NS), and LVEF (47 vs 48%, NS) were perfectly similar, but PVO2 remained significantly lower in RVI than in Non-RVI patients (71 vs 77%, p<0.05). After the 3-month CR/ET, the improvement in PVO2 was similar (+11% vs +13%, NS) in the two groups. However, PVO2 remained significantly lower in RVI than in Non-RVI patients (78% vs 87%, p<0.05).
Conclusion: Exercise capacity is reduced in RVI patients than in Non-RVI patients both early and late after AMI, although the magnitude of the increase by CR/ET was similar. This indicates that impaired RV contribution to exercise capacity persists in clinically diagnosed RVI patients.
- © 2013 by American Heart Association, Inc.