Clinical, electrocardiographic and echocardiographic findings in significant cardiac amyloidosis detected only at necropsy: comparison with cases diagnosed in life.

BACKGROUND: Currently, many cases of heart amyloidosis still fail to be diagnosed.
OBJECTIVE: To disclose factors related to the difficulty in attaining the diagnosis of cardiac amyloidosis.
METHODS: We compared the clinical, electrocardiographic and echocardiographic data of 17 patients in whom amyloidosis was diagnosed only at the necropsy (group I) with data from 9 patients in whom the disease was diagnosed in life (group II). The quantitative variables were compared by t-test and qualitative ones by Fisher's exact test. Significance was set at p< or = 0.05.
RESULTS: The two groups showed differences regarding age (group I: 75.29 +/- 11.61, group II: 58.67 +/- 11.07 years), association with other cardiac disease (group I: 52.94%, group II: 0%), low voltage at the ECG (group I: 17.65%, group II: 66.67%), and diastolic dysfunction at the echocardiogram (group I: 7.69%, group II: 62.50%). Some degree of left ventricular thickening was found in 75% of necropsy cases and 100% of controls (p=0.23), but wall thickness was lower in group I (free left ventricular wall: 1.20 +/- 0.28 cm versus 1.53 +/- 0.18 cm in group II, p=0.01). Systolic dysfunction was present in 57.89% of the cases, without significant difference between the groups.
CONCLUSION: Amyloidosis is diagnosed when the clinical, ECG, and echocardiogram patterns are "typical", but most of the cases fail to be diagnosed, especially in elderly people, due to the association with other cardiac diseases, lack of diastolic dysfunction at the echocardiogram and only a slightly thickened ventricular wall.