Angermann C, Spes C, Pongratz D
Z Kardiol. 1986 Sep;75(9):542-51.
Autopsy studies have shown that cardiomyopathy of Duchenne's muscular dystrophy (DMD) is characterized by fibrosis of the posterobasal and contiguous lateral wall of the left ventricle. This study was designed to determine whether stress testing would improve the sensitivity of echocardiography to detect secondary impairment of regional myocardial function. 12 patients aged 5 to 23 years with DMD were investigated. TM- and 2D-echocardiograms were performed before and during graded infusion of angiotensin (A) (0.5 to 5.0 mcg/min), and parameters of cardiac function analyzed. Satisfactory echocardiograms were obtained in all patients. Stress testing with A proved feasible in DMD and did not interfere with echocardiography. Before A all patients were in regular sinus rhythm and free of cardiac symptoms. Left ventricular function was normal in 9 patients and considered abnormal in 3 patients with hypokinesis and increased echo intensity of the posterobasal and lateral wall (2D short axis view) and/or a posterior wall to septal amplitude ratio of less than or equal to 1.1 (TM-echocardiogram). During A mean blood pressure rose and heart rate dropped significantly. 9 patients had marked supraventricular arrhythmias, 8 complained of dyspnea, cough or chest pain. Hypo- or akinesis of the posterobasal and sometimes the lateral wall was seen in 8, and a posterior wall to septal amplitude ratio of less than or equal to 1.1 in 9 patients. 3 patients, all with a muscle score of 60% or higher, remained free of symptoms and had no regional contraction abnormalities. Thus, clinical symptoms during A suggested latent congestive heart failure in many of the patients, and echocardiography identified provokable contraction abnormalities of such segments of the ventricular wall known to be most frequently involved in the dystrophic process in DMD. Stress testing revealed a correlation between clinical symptoms, abnormal echocardiographic findings and extent of the skeletal muscle disease in our study group. Physical limitation seems to protect the heart against demands that would otherwise cause earlier clinical manifestation of the cardiomyopathy in DMD.
尸检研究表明，杜氏肌营养不良症（DMD）的心肌病特征为左心室后基底壁及相邻侧壁纤维化。本研究旨在确定负荷试验是否会提高超声心动图检测局部心肌功能继发性损害的敏感性。对12例年龄在5至23岁的DMD患者进行了研究。在分级输注血管紧张素（A）（0.5至5.0 mcg/分钟）之前及期间进行了TM和二维超声心动图检查，并分析了心功能参数。所有患者均获得了满意的超声心动图。A负荷试验在DMD患者中证明可行，且不干扰超声心动图检查。在使用A之前，所有患者均为窦性心律且无心脏症状。9例患者左心室功能正常，3例患者左心室功能异常，表现为后基底壁和侧壁运动减弱（二维短轴视图）及回声增强，和/或后壁与室间隔幅度比值小于或等于1.1（TM超声心动图）。在使用A期间，平均血压升高，心率显著下降。9例患者出现明显的室上性心律失常，8例患者主诉呼吸困难、咳嗽或胸痛。8例患者可见后基底壁有时还有侧壁运动减弱或消失，9例患者后壁与室间隔幅度比值小于或等于1.1。3例肌肉评分60%或更高的患者无症状，也无局部收缩异常。因此，使用A期间的临床症状提示许多患者存在潜在的充血性心力衰竭，超声心动图显示已知在DMD营养不良过程中最常受累的心室壁节段存在可诱发的收缩异常。在我们的研究组中，负荷试验揭示了临床症状、异常超声心动图表现与骨骼肌疾病程度之间的相关性。身体活动受限似乎可保护心脏免受那些否则会导致DMD心肌病更早临床表现的需求影响。
