Yoshihito Saijo1, Erik Van Iterson2, Maria Vega Brizneda1, Milind Y Desai1, Harry M Lever1, Nicholas G Smedira3, Per Wierup3, Maran Thamilarasan1, Zoran B Popović1, Richard A Grimm1, Brian P Griffin1, Bo Xu1. 1. Section of Cardiovascular Imaging, Robert and Suzanne Tomsich Department of Cardiovascular Medicine, Sydell and Arnold Miller Family Heart, Vascular and Thoracic Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA. 2. Section of Preventive Cardiology and Rehabilitation, Heart and Vascular Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA. 3. Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
Abstract
AIMS: We sought to assess the relationship between left atrial (LA) strain mechanics and exercise intolerance, and to evaluate the prognostic impact of LA strain mechanics on clinical deterioration necessitating septal reduction therapy in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: Consecutive HCM patients who underwent exercise stress echocardiography and cardiopulmonary exercise testing on the same day between October 2015 and April 2019 were enrolled prospectively. LA strain mechanics were analysed using speckle tracking echocardiography. LA stiffness was calculated as the ratio of E/e' ratio to LA reservoir strain. The study cohort was divided into four groups based on the quartile of percent-predicted peak VO2, and exercise intolerance was defined as the lowest quartile (≤51%). Of 532 patients studied (mean age: 51 ± 15 years, 42% female), 138 patients demonstrated exercise intolerance. As exercise capacity worsened, LA strain mechanics worsened along a continuum (P < 0.001). LA contractile strain with a cut-off of -13.9% was optimal at identifying exercise intolerance. On multivariable analysis, worse LA contractile strain was an independent predictor for exercise intolerance (P = 0.002). Of patients with left ventricular outflow tract obstruction, patients with LA stiffness worse than the median value (≥0.41) were significantly more likely to require septal reduction therapy than those with better LA stiffness (P = 0.026). CONCLUSION: Worse LA contractile strain was an independent predictor for exercise intolerance in HCM. Patients with worse LA stiffness had a higher probability of clinical deterioration necessitating septal reduction therapy. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: We sought to assess the relationship between left atrial (LA) strain mechanics and exercise intolerance, and to evaluate the prognostic impact of LA strain mechanics on clinical deterioration necessitating septal reduction therapy in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: Consecutive HCM patients who underwent exercise stress echocardiography and cardiopulmonary exercise testing on the same day between October 2015 and April 2019 were enrolled prospectively. LA strain mechanics were analysed using speckle tracking echocardiography. LA stiffness was calculated as the ratio of E/e' ratio to LA reservoir strain. The study cohort was divided into four groups based on the quartile of percent-predicted peak VO2, and exercise intolerance was defined as the lowest quartile (≤51%). Of 532 patients studied (mean age: 51 ± 15 years, 42% female), 138 patients demonstrated exercise intolerance. As exercise capacity worsened, LA strain mechanics worsened along a continuum (P < 0.001). LA contractile strain with a cut-off of -13.9% was optimal at identifying exercise intolerance. On multivariable analysis, worse LA contractile strain was an independent predictor for exercise intolerance (P = 0.002). Of patients with left ventricular outflow tract obstruction, patients with LA stiffness worse than the median value (≥0.41) were significantly more likely to require septal reduction therapy than those with better LA stiffness (P = 0.026). CONCLUSION: Worse LA contractile strain was an independent predictor for exercise intolerance in HCM. Patients with worse LA stiffness had a higher probability of clinical deterioration necessitating septal reduction therapy. Published on behalf of the European Society of Cardiology. All rights reserved.