Ridolfi R L, Bulkley B H, Hutchins G M
Am J Med. 1977 May;62(5):677-86. doi: 10.1016/0002-9343(77)90870-1.
Cardiac amyliodosis is frequently associated with major electrocardiographic conduction disturbances; but that these disturbances are due to infiltrative destruction of the conduction system by amyloid is unclear. We studied the conduction systems in 23 autopsy patients with cardiac amyloidosis (group 1) (mild in seven, moderate in five and severe in 11), 21 (91 per cent) of whom had had abnormalities of conduction or rhythm during life. For comparison, we examined the conduction system in 23 control subjects matched in age and heart weight (group 2). Of the 23 patients in group 1, only three had extensive amyloidosis of the conduction system; in all three, electrocardiograms showed first degree atrioventricular block and left anterior hemiblock. A more common morphologic abnormality of the conduction system was severe sinoatrial node fibrosis present in seven (30 per cent) patients, and idiopathic atrophy and fibrosis of the bundle branches present in six (26 per cent) patients. None of the patients in group 2 had severe sinoatrial node fibrosis, but two (9 per cent) had idiopathic atrophy and fibrosis of the left bundle branch. Marked fibrosis of the sinus node was more frequent in patients with severe or moderate amyloid, but fibrosis of the bundle branch did not appear to be related to the amount of amyloid elsewhere in the heart. Varying degrees of atrioventricular and bundle branch block were also present in six patients with no morphologic abnormalities of the conduction system. Thus, conduction and rhythm disturbances are frequent in cardiac amyloidosis, but direct amyloid infiltration of the specialized conduction tissue of the heart does not account for the majority of these disturbances. Whether the increased incidence of fibrosis of the conduction system in group 1 compared to that in group 2 relates to the infiltrative myocardiopathy is uncertain.
心脏淀粉样变性常伴有严重的心电图传导障碍；但这些障碍是否是由于淀粉样物质对传导系统的浸润性破坏所致尚不清楚。我们研究了23例心脏淀粉样变性尸检患者（第1组）（轻度7例，中度5例，重度11例），其中21例（91%）生前有传导或节律异常。为作比较，我们检查了23例年龄和心脏重量相匹配的对照者的传导系统（第2组）。第1组的23例患者中，只有3例有广泛的传导系统淀粉样变性；所有这3例患者的心电图均显示一度房室传导阻滞和左前分支阻滞。传导系统更常见的形态学异常是7例（30%）患者存在严重的窦房结纤维化，6例（26%）患者存在特发性束支萎缩和纤维化。第2组患者均无严重的窦房结纤维化，但2例（9%）有左束支特发性萎缩和纤维化。严重或中度淀粉样变性患者中窦房结明显纤维化更为常见，但束支纤维化似乎与心脏其他部位的淀粉样物质含量无关。6例传导系统无形态学异常的患者也存在不同程度的房室传导阻滞和束支阻滞。因此，心脏淀粉样变性中传导和节律障碍很常见，但心脏特殊传导组织的直接淀粉样浸润并不能解释这些障碍的大多数情况。第1组与第2组相比传导系统纤维化发生率增加是否与浸润性心肌病有关尚不确定。
