Nonlinear Dynamics of Left Ventricular Mass Remodeling in Chagas Cardiomyopathy

Left ventricular (LV) mass remodeling in chronic Chagas cardiomyopathy (CCC) is progressive, but whether its population-level dynamics follow nonlinear patterns and track mortality remains unexplored. Fifty SEARCH-Rio outpatients were followed for 10 years (40 survivors, 10 nonsurvivors). Serial echocardiography provided paired LV mass measurements fitted to the logistic equation x = {middle dot}x{middle dot}(1-{gamma}{middle dot}x). Lyapunov exponents (LE) were computed from consecutive inter-patient derivatives. A clinical risk score was developed using Firth penalized logistic regression with bootstrap validation (B = 1,000) and Cox-Firth sensitivity. LV mass data were fitted to the logis