Right ventricular dysfunction and exercise capacity after inferior (posterior) wall acute myocardial infarction.
Tissue Doppler echocardiography is a novel technique that can be used to diagnose right ventricular (RV) systolic dysfunction. Until recently, there have been no data on the influence of tissue Doppler-derived RV systolic dysfunction on exercise capacity after inferior (posterior) myocardial infarction (MI). We studied 90 consecutive patients (76% men, mean age 61 ± 10 years) with first inferior ST-segment elevation MI and left ventricular ejection fraction ≥45%. RV systolic dysfunction was defined as RV systolic myocardial velocity <11.5 cm/s at the basal segment of the RV free wall assessed by pulse tissue Doppler. Patients were categorized as with or without RV systolic dysfunction (RV systolic myocardial velocity 9.34 ± 1.36 and 13.74 ± 1.58 cm/s, respectively). A cardiopulmonary exercise test was performed before or soon after discharge (day 14 ± 10). Patients with RV systolic dysfunction had lower oxygen consumption assessed as percent predicted oxygen uptake in liters per minute and milliliters per kilogram per minute at their anaerobic threshold (61 ± 11% vs 69 ± 17%, p = 0.007; 53 ± 12% vs 61 ± 19%, p = 0.012, respectively) and at peak exercise (71 ± 12% vs 83 ± 16%, p = 0.0001; 62 ± 14% vs 74 ± 21%, p = 0.002, respectively). Multivariate regression analysis revealed that the following independent factors negatively influenced exercise capacity: RV systolic dysfunction, female gender, age, lower body mass index, current smoking, and maximal troponin I concentration. In conclusion, we found decreased exercise capacity in patients with systolic RV dysfunction assessed by pulse tissue Doppler in patients with inferior (posterior) wall acute MI despite preserved left ventricular function.
Department of Cardiology, Postgraduate Medical School, Grochowski Hospital, Warsaw, Poland. krzysztofsmarz@hotmail.com
Krzysztof
K
Smarz
Beata
B
Zaborska
Tomasz
T
Jaxa-Chamiec
Paweł
P
Maciejewski
Andrzej
A
Budaj
D018619:Echocardiography, Doppler, Pulsed / Q000379:methods*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D056989:Inferior Wall Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016278:Ventricular Function, Right