Abstract 17189: Radiation-induced Accelerated Multi-valve Disease In A Patient With Subaortic Membrane

Abstract

A 69-year-old woman with history of right breast cancer status post lumpectomy and radiation (4.2 cGy) 18 months prior, presented with progressive NYHA class III dyspnea. TTE obtained prior to her cancer diagnosis was notable for normal LV size and wall thickness, a subaortic membrane with systolic mean Doppler gradient of 21 mmHg and a mildly thickened mitral valve without significant stenosis or regurgitation. On presentation, TTE was notable for severely increased concentric LV wall thickness (LV mass index 140 g/m 2 ), preserved ejection fraction, increased RV wall thickness, subaortic stenosis with systolic mean Doppler gradient 35 mmHg, moderate-severe aortic regurgitation, thickened mitral valve with posterior leaflet tethering and anterior leaflet override causing severe mitral regurgitation and moderate mitral stenosis (valve area 1.7 cm 2 by pressure half-time). She underwent a surgical intervention with septal myectomy, subaortic membrane resection, aortic root reconstruction, aortic and mitral valve replacement with bioprostheses. She did well post-operatively and had complete resolution of symptoms following cardiac rehabilitation. Radiation-induced valvular heart disease is linked to the total dose of radiation, use of sequential chemotherapy and time since irradiation, with a typical latency of 10-20 years. However, there is paucity of data regarding the influence of these variables in patients with pre-existing valve disease. This case illustrates dramatic acceleration of underlying aortic and mitral valve pathology in a patient with a subaortic membrane, 18 months after radiation. We also noted development of significant concentric LV hypertrophy that was disproportionate to the degree of obstruction across the sub-aortic membrane. Potential candidates for radiation therapy must be carefully screened for pre-existing valve disease, which should warrant increased vigilance and early screening for progressive valve disease.