Association of Non-Severe Aortic Stenosis With Left Ventricular Reverse Remodeling and Clinical Outcomes After Cardiac Resynchronization Therapy.

Background: The clinical impact of non-severe aortic stenosis (AS) on the response to cardiac resynchronization therapy (CRT) remains unclear. We investigated whether non-severe AS affects left ventricular (LV) reverse remodeling and long-term outcomes after CRT. Methods and Results: We retrospectively analyzed 181 consecutive patients with chronic heart failure (mean age 70 years; 76% male) who underwent CRT at a single center. Patients were classified into a non-severe AS group (mild or moderate AS) and a no AS group. The primary endpoint was a composite of all-cause death and heart failure hospitalization. LV reverse remodeling, defined as a ≥15% reduction in LV end-systolic volume at 6 months, was evaluated as a secondary endpoint. Patients with non-severe AS were older and had a higher baseline LV ejection fraction. LV reverse remodeling occurred less frequently in the non-severe AS group (39% vs. 66%; P<0.05). Non-severe AS was independently associated with lower likelihood of LV reverse remodeling. During a median 3.5-year follow up, cumulative incidence of the composite endpoint was higher in the non-severe AS group. In multivariable Cox analysis, non-severe AS independently predicted adverse outcomes (hazard ratio 2.19; 95% confidence interval 1.19-4.16; P=0.01). Conclusions: Non-severe AS is associated with attenuated LV reverse remodeling and worse outcomes after CRT and may represent a modifier of CRT response.