Transcatheter aortic valve replacement (TAVR) is a minimally invasive procedure to replace narrowed aortic valves that fail to properly open. Following this procedure, however, left ventricular (LV) hypertrophy and myocardial fibrosis persist and are linked to worse prognosis. Renin-angiotensin system (RAS) inhibition can protect against these risks and in response to profibrotic stimuli such as aortic stenosis (AS).
A multicenter, retrospective study was performed to evaluate the clinical effect of RAS inhibition following successful TAVR. Clinical outcomes and echocardiographic evolution were evaluated and compared in2785 patients that underwent TAVR between 2007 and 2017. Baseline data were prospectively collected, and pre-specified follow-up was performed. RAS inhibitor type and dose was recorded at discharge and a matched comparison was performed according to their prescription.
Protective effect of RAS inhibitors
Patients treated with RAS inhibitors (n=1,622) had reduced left ventricular volume, hypertrophy and cardiovascular mortality at 3-year follow-up (odds ratio: 0.59; 95% confidence interval: 0.41 to 0.87; P=0.007). This was irrespective of baseline differences. Inhibitor treatment also showed a global cardiovascular protective effect, including a decrease in new-onset of atrial fibrillation, cerebrovascular events and readmissions. This improved clinical outcome may in part be explained by a LV positive remodeling.
Future studies with RAS inhibitors
RAS inhibitors after TAVR resulted in a global cardiovascular protective effect along with a lower rate of cardiac mortality. It is still unclear how RAS inhibition improves cardiovascular outcomes in TAVR patients and whether this holds true for patients undergoing surgical valve replacement. RASTAVI (NCT03201185), a randomized controlled trial currently underway, will help to clarify many of these findings.
Author: Catherine Sorbara
Original Article: JACC. 2019. 74. 631-41.