Rate of Progression of Aortic Stenosis and its Impact on Outcomes in Patients With Radiation-Associated Cardiac Disease: A Matched Cohort Study.

Objectives The aim of this study was to study differences in progression of aortic stenosis (AS) in patients with mediastinal radiotherapy (XRT)-associated moderate AS versus a matched cohort during the same time frame, and to ascertain need for aortic valve replacement (AVR) and longer-term survival. Background Rate of progression of XRT-associated moderate AS and its impact on outcomes is not well-described. Methods We included 81 patients (age 61 ± 13 years; 57% female) with at least XRT-associated moderate AS (aortic valve area [AVA] 1.05 ± 0.3 cm 2 ; mean gradient 24 ± 10 mm Hg) who had ≥2 transthoracic echocardiograms (TTEs) 1 year apart and matched them in a 1:2 fashion on the basis of age, sex, and AVA with those without prior XRT. Serial aortic valve gradients and AVA were recorded. AVR and longer-term all-cause mortality during follow-up were recorded. Results A total of 100% of patients had 1, a total of 71% had 2, and 39% had 3 follow-up TTEs. Before AVR, mean AVG and AVA were not significantly different between XRT and comparison groups. At 3.6 ± 2.0 years from baseline TTE, 146 (60%) underwent AVR (16% transcatheter), with significantly more patients in the XRT group undergoing AVR (80% vs. 50%; p < 0.01), at a much shorter time (2.9 ± 1.6 years vs. 4.1 ± 2.4 years; p < 0.01). At 6.6 ± 4.0 years from the initial TTE, 49 (20%) patients died, with a significantly higher mortality in the XRT group (40% vs. 11%; p < 0.01), with prior XRT associated with increased longer-term mortality, whereas AVR was associated with improved longer-term survival. Conclusions In patients with moderate AS, those with prior XRT have a similar rate of progression of AS versus a comparison group. A higher proportion of patients in the XRT group were referred for AVR at a shorter time from baseline TTE. Despite that, the XRT patients had significantly higher longer-term mortality, and prior exposure to XRT was associated with significantly increased longer-term mortality. [ABSTRACT FROM AUTHOR]