Left Atrial Stiffness Index as a Predictor of Effort Intolerance and Hemodynamics Evaluated by Invasive Exercise Stress Testing in Degenerative Mitral Regurgitation.
Kosuke TakahariHitoshi SusawaHiroto UtsunomiyaAkane TsuchiyaAtsuo MogamiHajime TakemotoKanako IzumiYusuke UedaKiho ItakuraYukiko NakanoPublished in: The American journal of cardiology (2023)
In patients with degenerative mitral regurgitation (DMR), peak oxygen consumption is the significant prognostic factor, and exercise intolerance has been considered a trigger for surgical intervention. The significant mitral regurgitation (MR) induces left atrial (LA) remodeling, but the significance of LA stiffness calculated by the ratio of E/e' to LA reservoir strain in degenerative MR has not been elucidated. A total of 30 patients with asymptomatic or minimally symptomatic grade ≥III + DMR underwent the cardiopulmonary exercising test simultaneously with invasive hemodynamic assessment. LA stiffness index significantly correlated with exercise hemodynamic deterioration, including pulmonary arterial wedge pressure (r = 0.71, p <0.01), systolic pulmonary arterial pressure at peak exercise (r = 0.73, p <0.01), and pulmonary circulatory reserve (mean pulmonary arterial pressure/cardiac output slope, r = 0.45, p = 0.012). Multiple linear regression analysis revealed that the higher LA stiffness index was significantly associated with decreased percent predicted peak oxygen consumption (per 0.1 increase, β -4.0, 95% confidence interval -6.9 to -1.3, p <0.01) independently of MR deterioration during exercise. In conclusion, increased LA stiffness was associated with exercise intolerance through hemodynamic deterioration during exercise in patients with asymptomatic or minimally symptomatic severe DMR.