Honda Takeaki, Tamano Kouichi, Takahashi Masaki, Kobayashi Tsutomu, Uetake Shuichiro, Seta Hitoshi
Department of Hypertension and Cardiorenal Medicine, Dokkyo University School of Medicine, Kitakobayashi 880, Mibu-machi, Shimotsuga-gun, Tochigi 321-0293.
J Cardiol. 2002 Mar;39(3):141-50.
Midwall fractional shortening (MFS) is a useful index to evaluate left ventricular myocardial function in patients with essential hypertension. The study investigated the prevalence and characterization of low MFS in hemodialysis patients.
MFS was calculated from M-mode echocardiograms in 67 patients (34 males, 33 females) receiving maintenance hemodialysis in whom fractional shortening was normal. Plasma levels of atrial and brain natriuretic peptides were also measured in these patients before and after hemodialysis. MFS was evaluated by stress-corrected MFS (ratio of observed to predicted MFS). The relationship of MFS to circumferential end-systolic stress in 122 healthy subjects was used to calculate the predicted MFS.
Stress-corrected MFS was depressed in 18 of the 67 patients (26.9%). In the low MFS group, duration of hypertension was significantly longer (p < 0.05), wall thickness was significantly greater (p < 0.001), left ventricular dimension was significantly smaller (p < 0.0001), and relative wall thickness was significantly greater (p < 0.0001) than in the normal MFS group. Reduction of brain natriuretic peptide level by hemodialysis in the low MFS group was significantly higher (p < 0.05) than in the normal MFS group.
Depression of stress-corrected MFS may be common in hemodialysis patients. Long duration of hypertension and concentric geometry of the left ventricle occur in patients with low MFS.
室壁中层缩短分数（MFS）是评估原发性高血压患者左心室心肌功能的一项有用指标。本研究调查了血液透析患者中低MFS的患病率及特征。
对67例接受维持性血液透析且缩短分数正常的患者（34例男性，33例女性）进行M型超声心动图检查以计算MFS。还对这些患者血液透析前后的心房利钠肽和脑利钠肽血浆水平进行了测量。通过应力校正MFS（观察到的MFS与预测的MFS之比）来评估MFS。利用122名健康受试者中MFS与收缩末期圆周应力的关系来计算预测的MFS。
67例患者中有18例（26.9%）应力校正MFS降低。在低MFS组中，高血压病程明显更长（p<0.05），室壁厚度明显更大（p<0.001），左心室尺寸明显更小（p<0.0001），相对室壁厚度明显更大（p<0.0001），均高于正常MFS组。低MFS组血液透析后脑利钠肽水平的降低明显高于正常MFS组（p<0.05）。
应力校正MFS降低在血液透析患者中可能很常见。低MFS患者存在高血压病程长和左心室向心性几何形态的情况。
