Neovascularization of native cardiac valves, and correlation with histopathologic, clinical, and radiologic features

Native cardiac valves in the setting of chronic injury undergo remodeling that includes fibrous thickening and dystrophic calcification, as well as neovascularization, that result in abnormal valve function. In order to characterize the presence of neovascularization in valves, a retrospective review of 1246 sequentially reviewed native cardiac valves of all types was performed, with correlation with other histopathologic features, and clinical and echocardiographic findings. Neovascularization was present in 55.5% of cases, with the greatest prevalence amongst aortic valves. While microvasculature (representing capillaries, venules, and/or lymphatics) was at least present in all cases of valves with neovascularization, arterial vessels were never identified in valves without also the finding of concomitant microvasculature present. Patients with neovascularization had a greater mean age and body mass index compared to those without, and the proportions of cases with significant coronary artery disease, dyslipidemia, diabetes mellitus, rheumatic fever, and malignancy were greater in the setting of valves with neovascularization compared to cases without. The rate of neovascularization increased with degree of valve thickening and/or calcification, and stenosis; in contrast, neovascularization was observed at a greater rate with decreasing degrees of regurgitation. The prevalence rates of hemosiderin-laden macrophages, osseous metaplasia, chondromatous metaplasia, smooth muscle, and chronic inflammation were greater in valves with neovascularization compared to valves without. Neovascularization within native cardiac valves is a frequent histopathologic alteration associated with chronic valve disease, likely representing a constituent of structural remodeling that mediates and reflects chronic injury.