Saturday, November 03, 2007

Stroke and amyloidosis

Zubkov AY et al. Primary systemic amyloidosis with ischemic stroke as a presenting sign.

Neurology 2007 69:1136-1141.

Widjicks most patients (37/49) had light chain disease rather than primary or secondary systemic amyloidosis. In AL (amyloid due to light chain) the amyloid sheets are made by clonal expansion of the bone marrow rather than the liver as in the other types. Most strokes were large vessel, single arterial territory. 2 patients had cardiac amyloid and recurrent strokes. Most patients had abnormal ECHO c/w amyloid. There was no gender preference and the average age was 70. The median time to death was 7 months. A few patients presented with stroke (or TIA). The average delay of diagnosis was over nine months, that could be shortened by discovering amyloid on ECHO. The cardiac disease is a constrictive cardiomyopathy with CHF. The classic finding with increased echogenicity, valvular infiltration, and biventricular thickening is seen only in cardiac amyloidosis. LVEF is normal but strain and strain rate imaging are abnormal with long axis dysfunction and disproportionate impairment of longitudinal contraction. 70 % had cardioembolic strokes. Amyloid is actually common in atrial appendage (40/259 in surgical specimens) and may be associated with Atrial fibrillation. Clues thickened valves and septum can lead to diagnostic myocardial biopsy or referral to hematologist for additional evaluation.