Impact of mitral regurgitation severity and cause on effort tolerance-integrated stress myocardial perfusion imaging and echocardiographic assessment of patients with known or suspected coronary artery disease undergoing exercise treadmill testing Journal Article


Authors: Kampaktsis, P. N.; Albert, B. J.; Kim, J.; Xie, L. X.; Brouwer, L. R.; Tehrani, N. H.; Villanueva, M.; Choi, D. Y.; Szulc, M.; Ratcliffe, M. B.; Levine, R. A.; Devereux, R.; Weinsaft, J. W.
Article Title: Impact of mitral regurgitation severity and cause on effort tolerance-integrated stress myocardial perfusion imaging and echocardiographic assessment of patients with known or suspected coronary artery disease undergoing exercise treadmill testing
Abstract: Background: Mitral regurgitation (MR) has the potential to impede exercise capacity; it is uncertain whether this is because of regurgitation itself or the underlying cause of valvular insufficiency. Methods and Results: The population comprised 3267 patients who underwent exercise treadmill myocardial perfusion imaging and transthoracic echocardiography within 6±8 days. MR was present in 28%, including 176 patients (5%) with moderate or greater MR. Left ventricular systolic function significantly decreased and chamber size increased in relation to MR, paralleling increments in stress and rest myocardial perfusion deficits (all P<0.001). Exercise tolerance (metabolic equivalents of task) decreased stepwise in relation to graded MR severity (P<0.05). Workload was significantly lower with mild versus no MR (mean±SD, 9.8±3.0 versus 10.1±3.0; P=0.02); magnitude of workload reduction significantly increased among patients with advanced versus those with mild MR (mean±SD, 8.6±3.0 versus 9.8±3.0; P<0.001). MR-associated exercise impairment was accompanied by lower heart rate and blood pressure augmentation and greater dyspnea (all P<0.05). Both functional and nonfunctional MR subgroups demonstrated significantly decreased effort tolerance in relation to MR severity (P≤0.01); impairment was greater with functional MR (P=0.04) corresponding to more advanced left ventricular dysfunction and dilation (both P<0.001). Functional MR predicted reduced metabolic equivalent of task–based effort (B=−0.39 [95% CI, −0.62 to −0.17]; P=0.001) independent of MR severity. Among the overall cohort, advanced (moderate or greater) MR was associated with reduced effort tolerance (B=−1.36 [95% CI, −1.80 to −0.93]; P<0.001) and remained significant (P=0.01) after controlling for age, clinical indexes, stress perfusion defects, and left ventricular dysfunction. Conclusions: MR impairs exercise tolerance independent of left ventricular ischemia, dysfunction, and clinical indexes. Magnitude of exercise impairment parallels severity of MR. © 2019 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Keywords: coronary artery disease; mitral regurgitation; exercise stress test
Journal Title: Journal of the American Heart Association
Volume: 8
Issue: 5
ISSN: 2047-9980
Publisher: Wiley Blackwell  
Date Published: 2019-03-05
Start Page: e010974
Language: English
DOI: 10.1161/jaha.118.010974
PUBMED: 30808228
PROVIDER: scopus
PMCID: PMC6474934
DOI/URL:
Notes: Article -- Export Date: 1 May 2019 -- Source: Scopus
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  1. Lola Xie
    4 Xie