Higher doses of renin angiotensin system (RAS) blockade were found to be associated with improved survival and beneficial left ventricular remodeling 3 years after transcatheter aortic valve replacement (TAVR), according to a study published in the Canadian Journal of Cardiology.
Researchers retrospectively assessed 323 patients on whom TAVR was conducted with different doses of RAS blockade: group 1 (n=98; no RAS blockade), group 2 (n=109; 25% of maximum daily dose), group 3 (n=77; 50% of maximum daily dose), and group 4 (n=39; full daily dose). Demographic characteristics were as follows: group 1 (median age, 79.8±9.3; 46% women), group 2 (81.3±6.4; 38% women), group 3 (80.4±6.4; 47% women), and group 4 (79.4±7.2; 56% women).
A trend toward better overall survival was observed at the 3-year follow-up in patients who received higher doses of RAS blockade (56% with no RAS blockade; 66% with the 25% dose; 79% with the 50% dose; and 78% with the full dose; P =.063). The difference in survival was still significant after adjusting for baseline characteristics (P =.042).
RAS blockade dose was found to be an independent predictor of all-cause mortality at 3 years in a multivariate Cox regression analysis (hazard ratio, 0.72; 95% CI 0.54-0.97; P =.03) in addition to New York Heart Association class ≥III and left ventricular ejection fraction at baseline. A greater reduction in left ventricular mass index was observed during the follow-up with higher doses of RAS blockade.
Study limitations include its retrospective nature, the relatively small number of patients, and the availability of complete echocardiographic follow-up for only half of the cohort.
“The present study showed for the first time that the impact of RAS blockade treatment on clinical outcome after TAVR is dose-dependent,” noted the researchers. “Patients who received lower doses or no treatment had significantly higher all-cause mortality compared [with] those with higher doses. In addition to clinical outcome regression of left ventricular mass index after TAVR was associated with RAS blockade dose.”
Ledwoch J, Olbrich I, Poch F, et al. Dose dependent effect of renin angiotensin system blockade following transcatheter aortic valve replacement [published online August 21, 2020]. Can J Cardiol. doi: 10.1016/j.cjca.2020.08.014