Evidence for risk stratification using exercise stress echocardiography (ESE) in patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS) is currently lacking. Cardiac power output (CPO) has demonstrated prognostic value in patients undergoing TAVI for severe AS. This study investigated prognoses in patients undergoing TAVI for severe AS and to explore the additional information that ESE can provide for risk stratification. In this retrospective observational study, we included 96 consecutive patients who underwent TAVI for severe AS and patients with preserved left ventricular (LV) ejection fraction (≥ 50%) who underwent ESE at 3-6months after TAVI. CPO was calculated as 0.222 × cardiac output × mean blood pressure/LV mass, where 0.222 was the conversion constant to W/100g of the LV myocardium. All patients were followed up for all-cause mortality and hospitalization for heart failure. Of the 96 patients, 3 were excluded and 93 patients (82.0years; 45.2% male) were included in this study. During a median follow-up period of 1446 (1271-1825) days, the composite end point was reached in 17 patients. Multivariable Cox regression analysis revealed that CPO at rest and the change in CPO from rest to exercise (ΔCPO) were independently associated with the composite end point (hazard ratio = 0.278, p = 0.023). The addition of ΔCPO resulted in an incremental value of the model containing clinical and resting echocardiography variables (p = 0.030). This study suggests that resting CPO and exercise-induced changes in CPO are useful for risk stratification of patients undergoing TAVI for severe AS.
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