北村 浩一¹, 古川 啓三¹, 西田 和夫¹, 辻 光¹, 海老沢 哲也¹, 樋上 雅一¹, 幸田 正明¹, 盛川 洋一¹, 中川 博昭¹, 杉原 洋樹¹, 朝山 純¹, 勝目 紘¹, 伊地知 浜夫¹, 斎藤 良夫², 国重 宏²

Hirokazu KITAMURA¹, Keizo FURUKAWA¹, Kazuo NISHIDA¹, Hikari TSUJI¹, Tetuya EBIZAWA¹, Masaichi HIGAMI¹, Masaaki KOHDA¹, Yohichi MORIKAWA¹, Hiroaki NAKAGAWA¹, Hiroki SUGIHARA¹, Jun ASAYAMA¹, Hiroshi KATSUME¹, Hamao IJICHI¹, Yoshio SAITO², Hiroshi KUNISHIGE²

¹京都府立医科大学第二内科, ²松下病院第三内科

¹The Second Department of Internal Medicine, Kyoto Prefectural University of Medicine, ²The Third Department of Internal Medicine, Matsushita Hospital

キーワード : Mitral stenosis, Left ventricular systolic performance, Dynamic exercise echocardiography

　To assess the correlation among exercise tolerance, mitral valve are (MVA) and the left ventricular (LV) systolic performance, dynamic exercise echocardiography was performed on 21 patients with mitral stenosis (MS). The patients were divided into 3 groups by the attained work load and exercise time: 6 patients whose attained work load was 25 watts and exercise time was less than 6 minutes (group I); 7 patients, 50 watts and less than 9 minutes (group II); and 8 patients, 75 watts and 9 minutes (group III). MVA in group I was smaller than that in group III, however, the correlation between exercise time and MVA was poor (r=0.48). Resting LV end-diastolic and end systolic dimensions (EDD, ESD) and systolic functions (% shortening fraction, mean Vcf) showed no statistical differences among three groups. During exercise EDD decreased significantly in all three groups, but at peak exercise it did not show significant differences among three groups. ESD, whereas, decreased significantly with exercise in all three groups, but at peak exercise ESD in group I was significantly larger than that in group III (p<0.01).
　Per cent shortening fraction (% SF) decreased or unchanged with exercise in group I and in group II, while it increased significantly in group III (p<0.01). Mean Vcf in group I did not increase significantly with exercise, either. The extent of the increase in % SF and mean Vcf at peak exercise correlated well with exercise time (r=0.83, r=0.79).
　We conclude that exercise tolerance in MS patients is dependent not only MVA but also LV systolic function, and thus, exercise echocardiography is a useful method to evaluate the LV functional reserve in MS patients.