Fragola P V, Caló L, Luzi M, Mammarella A, Antonini G
Department of Internal Medicine, School of Cardiovascular Diseases, University of Rome Tor Vergata, Italy.
Cardiology. 1997 Nov-Dec;88(6):498-502. doi: 10.1159/000177398.
We utilized Doppler echocardiography to characterize left ventricular diastolic function in 42 patients with myotonic dystrophy (mean age 37 +/- 12 years, 64% male) who had no symptoms of heart failure and had normal left ventricular systolic function. Data were compared with those in 41 normal control subjects of similar age and gender. Heart rate, systemic blood pressure, and cardiac dimensions (wall thickness, left atrial and left ventricular cavity dimensions) were similar and not significantly different in patients and controls. As a group, patients showed significantly increased deceleration time and decreased rate of decline of flow velocity in early diastole (p < 0.0001 and p < 0.01, respectively) when compared to controls. Individual patient analysis showed that 10 (24%) of the 42 patients with myotonic dystrophy had 2 or more abnormal Doppler indexes of diastolic function consistent with a pattern of impaired left ventricular relaxation. The most common abnormalities were increased deceleration time (> 224 ms; 9 patients), prolonged isovolumic relaxation time (> 103 ms; 8 patients) and reduced rate of decline of flow velocity in early diastole (< 2.1 m/s2; 5 patients). In addition, peak early diastolic flow velocity was reduced (< 43 cm/s) in 3 patients and early to atrial peak flow velocity ratio was reduced (< 1) in 2 patients. Comparison of subgroups of patients with and without abnormal Doppler indexes showed no significant differences with regard to age, gender, heart rate, systemic blood pressure, severity of neuromuscular disease, and cardiac dimensions. After study, patients were clinically followed up for a mean period of 20 +/- 7 months (range 12-35). During observation no patients died and none experienced symptoms of heart failure. This Doppler echocardiographic analysis demonstrates that diastolic abnormalities may be present in patients with myotonic dystrophy, even in the absence of symptoms of cardiac failure or left ventricular systolic dysfunction. These diastolic abnormalities suggest an intrinsic myocardial abnormality in patients with myotonic dystrophy; however, whether they represent a preclinical phase of myocardial involvement or an intrinsic feature of the primary myocardial disease process in myotonic dystrophy remains to be elucidated.
我们利用多普勒超声心动图对42例强直性肌营养不良患者（平均年龄37±12岁，64%为男性）的左心室舒张功能进行了评估，这些患者无心力衰竭症状且左心室收缩功能正常。将数据与41例年龄和性别相仿的正常对照者进行比较。患者和对照者的心率、体循环血压及心脏大小（室壁厚度、左心房和左心室腔大小）相似，无显著差异。与对照组相比，强直性肌营养不良患者作为一个整体，舒张期减速时间显著延长，舒张早期血流速度下降速率降低（分别为p<0.0001和p<0.01）。对个体患者的分析显示，42例强直性肌营养不良患者中有10例（24%）有2项或更多舒张功能的异常多普勒指标，符合左心室舒张功能受损模式。最常见的异常为减速时间延长（>224毫秒；9例）、等容舒张时间延长（>103毫秒；8例）以及舒张早期血流速度下降速率降低（<2.1米/秒²；5例）。此外，3例患者舒张早期血流峰值速度降低（<43厘米/秒），2例患者舒张早期与心房血流峰值速度比值降低（<1）。对有和无异常多普勒指标的患者亚组进行比较，在年龄、性别、心率、体循环血压、神经肌肉疾病严重程度及心脏大小方面无显著差异。研究结束后，对患者进行了平均20±7个月（范围12 - 35个月）的临床随访。观察期间无患者死亡，也无患者出现心力衰竭症状。这项多普勒超声心动图分析表明，强直性肌营养不良患者即使没有心力衰竭症状或左心室收缩功能障碍，也可能存在舒张功能异常。这些舒张功能异常提示强直性肌营养不良患者存在心肌内在异常；然而，它们是否代表心肌受累的临床前期阶段或强直性肌营养不良原发性心肌疾病过程的内在特征仍有待阐明。
