Background: One of the first clinically detectable alterations in heart function in hypertrophic cardiomyopathy (HCM) is a decline in diastolic function. Diastolic dysfunction is caused by changes in intrinsic properties of cardiomyocytes or an increase in fibrosis. We investigated whether clinical and cellular parameters of diastolic function are different between male and female patients with HCM at the time of myectomy.

Methods and Results: Cardiac tissue from the interventricular septum of patients with HCM (27 women and 44 men) was obtained during myectomy preceded by echocardiography. At myectomy, female patients were 7 years older than male patients and showed more advanced diastolic dysfunction than men evident from significantly higher values for E/e′ ratio, left ventricular filling pattern, tricuspid regurgitation velocity, and left atrial diameter indexed for body surface. Whereas most male patients (56%) showed mild (grade I) diastolic dysfunction, 50% of female patients showed grade III diastolic dysfunction. Passive tension in HCM cardiomyocytes was comparable with controls, and myofilament calcium sensitivity was higher in HCM compared with controls, but no sex differences were observed in myofilament function. In female patients with HCM, titin was more compliant, and more fibrosis was present compared with men. Differences between female and male patients with HCM remained significant after correction for age.

Conclusions: Female patients with HCM are older at the time of myectomy and show greater impairment of diastolic function. Furthermore, left ventricular and left atrial remodeling is increased in women when corrected for body surface area. At a cellular level, HCM women showed increased compliant titin and a larger degree of interstitial fibrosis.

背景：肥厚型心肌病（HCM）心脏功能的第一个临床上可检测到的改变之一是舒张功能下降。舒张功能障碍是由心肌细胞内在特性的改变或纤维化增加引起的。我们调查了男性和女性HCM病人在我切除术时，舒张功能的临床和细胞参数是否有所不同。

方法和结果：HCM患者（27名女性和44名男性）的心室间隔的心脏组织是在超声心动图检查期间进行的全部切除术中获得的。在肌瘤切除术中，女性患者比男性患者大7岁，并且比男性患者表现出更严重的舒张功能障碍，这可以从E / e'值，左心室充盈模式，三尖瓣关闭不全速度和左心房直径（以体表指数）显着提高中看出。大多数男性患者（56％）表现为轻度（I级）舒张功能障碍，而50％的女性患者表现为III级舒张功能障碍。HCM心肌细胞的被动张力与对照组相当，并且HCM的肌丝钙敏感性高于对照组，但在肌丝功能上未观察到性别差异。在患有HCM的女性患者中，titin更顺应，与男性相比，存在更多的纤维化。校正年龄后，女性和男性HCM患者之间的差异仍然很显着。

结论：女性HCM患者在进行肌瘤切除术时年龄较大，并表现出更大的舒张功能损害。此外，校正体表面积后，女性的左心室和左心房重塑增加。在细胞水平上，HCM妇女表现出顺应性滴定蛋白增加和间质纤维化程度增加。