TY - JOUR
T1 - Cardiopulmonary Exercise Testing Determination of Functional Capacity in Mitral Regurgitation. Physiologic and Outcome Implications
AU - Messika-Zeitoun, David
AU - Johnson, Bruce D.
AU - Nkomo, Vuyisile
AU - Avierinos, Jean François
AU - Allison, Thomas G.
AU - Scott, Christopher
AU - Tajik, A. Jamil
AU - Enriquez-Sarano, Maurice
PY - 2006/6/20
Y1 - 2006/6/20
N2 - Objectives: This study was designed to evaluate prevalence, determinants, and clinical outcome implications of reduced functional capacity (FC) in patients with organic mitral regurgitation (MR). Background: Evaluation of FC by exercise testing is rarely performed in MR because little is known about the clinical determinants and outcome implications of FC. Methods: Cardiopulmonary exercise testing (CPET) was prospectively performed in 134 asymptomatic patients with organic MR to assess FC (peak oxygen consumption [Vo2]) simultaneously to Doppler-echocardiographic quantitation of MR (effective regurgitant orifice [ERO]) and left ventricular (LV) systolic and diastolic function. Results: Peak Vo2 was 26 ± 6 ml/kg/min (96 ± 16% of age-predicted), but varied widely (57% to 145% of predicted) and was markedly reduced (≤84% of predicted) in 19% of patients. Although ERO of MR was univariately associated with reduced FC (26 vs. 9% with ERO ≥40 vs. <40 mm2), independent determinants of reduced FC were LV diastolic function (higher E/E′ ratio, p = 0.006), atrial fibrillation (p = 0.01), and lower forward stroke volume (p = 0.03). Clinical events (death, heart failure, new atrial fibrillation) and clinical events or surgery were more frequent with than without reduced FC (3 years, 36 ± 14% vs. 13 ± 4%, p = 0.02; and 66 ± 11% vs. 29 ± 5%, p = 0.001, respectively), even adjusting (risk ratios 1.80 and 1.54 respectively, both p ≤ 0.03) for age and ERO. Conclusions: In asymptomatic organic MR, FC quantitatively assessed by CPET is unexpectedly markedly reduced in one out of every four to five patients. Reduced FC is independently determined by consequences rather than severity of MR and predicts increased subsequent clinical events. Therefore, CPET frequently reveals functional limitations not detected clinically and is an important tool in managing patients with organic MR.
AB - Objectives: This study was designed to evaluate prevalence, determinants, and clinical outcome implications of reduced functional capacity (FC) in patients with organic mitral regurgitation (MR). Background: Evaluation of FC by exercise testing is rarely performed in MR because little is known about the clinical determinants and outcome implications of FC. Methods: Cardiopulmonary exercise testing (CPET) was prospectively performed in 134 asymptomatic patients with organic MR to assess FC (peak oxygen consumption [Vo2]) simultaneously to Doppler-echocardiographic quantitation of MR (effective regurgitant orifice [ERO]) and left ventricular (LV) systolic and diastolic function. Results: Peak Vo2 was 26 ± 6 ml/kg/min (96 ± 16% of age-predicted), but varied widely (57% to 145% of predicted) and was markedly reduced (≤84% of predicted) in 19% of patients. Although ERO of MR was univariately associated with reduced FC (26 vs. 9% with ERO ≥40 vs. <40 mm2), independent determinants of reduced FC were LV diastolic function (higher E/E′ ratio, p = 0.006), atrial fibrillation (p = 0.01), and lower forward stroke volume (p = 0.03). Clinical events (death, heart failure, new atrial fibrillation) and clinical events or surgery were more frequent with than without reduced FC (3 years, 36 ± 14% vs. 13 ± 4%, p = 0.02; and 66 ± 11% vs. 29 ± 5%, p = 0.001, respectively), even adjusting (risk ratios 1.80 and 1.54 respectively, both p ≤ 0.03) for age and ERO. Conclusions: In asymptomatic organic MR, FC quantitatively assessed by CPET is unexpectedly markedly reduced in one out of every four to five patients. Reduced FC is independently determined by consequences rather than severity of MR and predicts increased subsequent clinical events. Therefore, CPET frequently reveals functional limitations not detected clinically and is an important tool in managing patients with organic MR.
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U2 - 10.1016/j.jacc.2006.02.043
DO - 10.1016/j.jacc.2006.02.043
M3 - Article
C2 - 16781383
AN - SCOPUS:33744997385
SN - 0735-1097
VL - 47
SP - 2521
EP - 2527
JO - Journal of the American College of Cardiology
JF - Journal of the American College of Cardiology
IS - 12
ER -