The value of the dynamic changes in cardiac power output in aortic stenosis patients following transcatheter aortic valve implantation: an exercise stress echocardiography study

AimsEvidence 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.MethodsIn 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 3-6 months after TAVI. CPO was calculated as 0.222 x cardiac output x mean blood pressure/LV mass, where 0.222 was the conversion constant to W/100 g of the LV myocardium. All patients were followed up for all-cause mortality and hospitalization for heart failure.ResultsOf the 96 patients, 3 were excluded and 93 patients (82.0 years; 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 (Delta CPO) were independently associated with the composite end point (hazard ratio = 0.278, p = 0.023). The addition of Delta CPO resulted in an incremental value of the model containing clinical and resting echocardiography variables (p = 0.030).ConclusionsThis study suggests that resting CPO and exercise-induced changes in CPO are useful for risk stratification of patients undergoing TAVI for severe AS.