Effects of the main green tea polyphenol epigallocatechin-3-gallate on cardiac involvement in patients with AL amyloidosis

Amyloid light chain (AL) amyloidosis is a rare disease with poor prognosis and limited therapeutic alternatives. Recently, one clinical case with cardiac involvement, as well as a compelling evidence of green tea polyphenol, epigallocatechin-3-gallate (EGCG), inducing the formation of benign aggregation products that do not polymerize into fibrils were published. This is a report of the cardiac effects of green tea consumption in these patients. Patients with known cardiac involvement in AL amyloidosis were examined by routine cardiovascular examinations that took place every 3–6 months. Of 59 patients with cardiac involvement, 11 revealed a decrease of at least 2 mm of interventricular wall thickness, after initiation of regular green tea consumption (GT). A matched historic control group (n = 22) was selected. Comprehensive echocardiography was conducted at every control examination and analyzed offline by two independent examiners. GT patients showed an improvement in New York Heart Association (NYHA) class from a median of 3 (25th, 75th percentiles: 2, 3) to 2 (2, 3), P = 0.038. Septal thickness decreased from 18 (18, 20) to 16 (16, 17) mm, P = 0.021. Left ventricular mass index decreased from 175 (154, 180) to 133 (128, 154) g/m2, P = 0.007. Comparing both groups, an increase in left ventricular ejection fraction could be found in the GT group, 65 (51, 73) versus 53 (47, 59)%, P = 0.012. These changes could not be observed in the control group. Consumption of green tea polyphenol EGCG in patients with cardiac involvement with AL amyloidosis causes a significant decrease in left ventricular wall thickness and mass, as well as an improvement in NYHA functional classification and left ventricular ejection fraction.