Laraki R
Service de médecine interne, hôpital de la Pitié, Paris, France.
Rev Med Interne. 1994 Apr;15(4):257-67. doi: 10.1016/s0248-8663(94)80030-8.
Cardiac amyloidosis, most often of AL type, is a non-exceptional disease as it represents 5 to 10% of non-ischemic cardiomyopathies. It realizes typically a restrictive cardiomyopathy. Nevertheless the wide diversity of possible presentation makes it a "big shammer" which must be evoked in front of every unexplained cardiopathy after the age of forty. If some associated manifestations can rapidly suggest the diagnosis, as a peripheric neuropathy especially a carpal tunnel syndrome or palpebral ecchymosis, cardiac involvement can also evolve in an apparently isolated way. The most suggestive paraclinic elements for the diagnosis are, in one hand, the increased myocardial echogenicity with a "granular sparkling" appearance seen throughout all walls of the left ventricle and, in the other hand, the association of a thickened left ventricle and a low voltage (electrocardiogram could also show pseudo-infarct Q waves). In front of such aspects, the proof of amyloidosis is brought by an extra-cardiac biopsy or by scintigraphy with labelled serum amyloid P component, so that the indications of endomyocardial biopsy are very limited today. The identification of the amyloid nature of a cardiopathy has an direct therapeutic implication: it contra-indicates the use of digitalis, calcium channel blockers and beta-blockers. The treatment of AL amyloidosis (chemotherapy with alkylant agents) remains very unsatisfactory especially in the cardiac involvement which is the most frequent cause of death (in AL amyloidosis). Last, cardiac amyloidosis is a bad indication for transplantation which results are burden by rapid progression of deposits especially in the gastro-intestinal tract and the nervous system.
心脏淀粉样变性,最常见的是AL型,并非罕见疾病,因为它占非缺血性心肌病的5%至10%。它通常表现为限制性心肌病。然而,其可能的表现形式多种多样,使其成为一个“大伪装者”,在40岁以后每例不明原因的心肌病面前都必须考虑到。如果一些相关表现能迅速提示诊断,如周围神经病变尤其是腕管综合征或眼睑瘀斑,心脏受累也可能以明显孤立的方式发展。诊断最具提示性的辅助检查因素,一方面是心肌回声增强,在左心室所有壁上均可见“颗粒状闪烁”外观,另一方面是左心室增厚与低电压并存(心电图也可能显示假性梗死Q波)。面对这些表现,淀粉样变性的确诊需通过心外活检或用标记血清淀粉样P成分的闪烁扫描法,因此如今心内膜活检的适应证非常有限。确定心肌病的淀粉样变性性质具有直接的治疗意义:它禁忌使用洋地黄、钙通道阻滞剂和β受体阻滞剂。AL淀粉样变性的治疗(用烷化剂化疗)仍然很不理想,尤其是在心脏受累方面,这是(AL淀粉样变性中)最常见的死亡原因。最后,心脏淀粉样变性是移植的不良适应证,移植结果因沉积物尤其是胃肠道和神经系统的快速进展而受到影响。