Relation of Aortic Valve Weight to Severity of Aortic Stenosis: A Clinico-Pathologic Study on Surgical Specimens.
Stefania Rizzo, Renato Razzolini, Susy Longhi, Giuseppe Tarantini, Massimo Napodano, Elena Abate, Chiara Fraccaro, Sabino Iliceto, Gino Gerosa, Gaetano Thiene, Cristina Basso. University of Padua Medical School, Italy
Background: The purpose of this study was to analyze the relation of aortic valve weight to both transvalvular gradient and area, with special regard to valve anatomy, size of calcific deposits, gender and body size.
Design: A total of 242 surgically excised stenotic aortic valves of patients (139 male, mean age 72±9 years) who had undergone preoperative cardiac catheterization and echocardiograms were weighed and examined with respect to the number of cusps (tricuspid vs. bicuspid), size of calcium deposits (“microaggregates” ≤4 mm vs. nodular “macroaggregates” >4 mm) and presence of cholesterol clefts. The relation between valve weight, gradient and area was studied.
Results: The transvalvular gradient was independent of gender or valve anatomy, and was linearly correlated with valve weight, either absolute (r = 0.33; p <0.01) or normalized by body surface area (r = 0.40; p <0.01). No correlation was evident between valve area and weight. Calcium macroaggregates were mainly present in males (51%) and in bicuspid valves (67%), and they were seen to be strong determinants of valve weight (2.84±1.03 g with macroaggregates vs. 1.63±0.56 g with microaggregates, p <0.001), but not of transvalvular gradient. Calcium microaggregates characterized tricuspid valves (62%), where transvalvular gradient was determined by valve weight (p = 0.0026). Finally, the heavier the valve the less frequent were hypercholesterolemia, valve cholesterol clefts, hypertension and diabetes mellitus.
Conclusions: In aortic stenosis due to dystrophic calcification, valve weight significantly correlates with transvalvular gradient when calcific deposits are arranged in diffuse microaggregates, a condition more commonly found in tricuspid valves and in females. Nodular calcium macroaggregates add to weight but not substantially to the severity of stenosis. Surprisingly, both valve weight and valve area were independent of plasma cholesterol concentration and cholesterol cleft deposits on the leaflets, suggesting that, once aortic stenosis is established, removing risk factors may have no influence on the severity of the disease.
Monday, February 28, 2011 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 46, Monday Morning