Left ventricular contractility and function in Kawasaki syndrome: effect of intravenous γ-globulin

To investigate the effect of Kawasaki syndrome on myocardial function, as well as the influence of high-dose intravenous gamma-globulin therapy on resolution of functional abnormalities, we studied 98 patients with Kawasaki syndrome during five time intervals from onset of illness: 1) 10 days or less, 2) 11-31 days, 3) 1-3 months, 4) 3-12 months, and 5) 1-3 years. Normal controls included 48 children under age 8 years, without known cardiovascular disease. Using two-dimensional directed M-mode echocardiograms, we obtained chamber dimensions, fractional shortening, rate-corrected velocity of shortening (Vcfc) adjusted for end-systolic wall stress, and early diastolic function parameters that included adjusted peak rates of left ventricular dimension change, wall thinning, and their respective timing. Left ventricular systolic and diastolic dimensions were larger (both p less than 0.01) in patients than in normal subjects in period 1. Stress-adjusted Vcfc was much lower in patients in the 3 months after disease onset; by period 5, contractility was comparable in patients and normal subjects. Adjusted indexes of early diastolic function did not differ significantly between patients and normal subjects. To investigate the effect of gamma-globulin, we analyzed data on 47 patients prospectively randomized to therapy with aspirin alone (n = 19, 40%) or to aspirin plus gamma-globulin, 400 mg/kg/day for 4 consecutive days (n = 28, 60%). In period 1, before treatment, the two groups had mean fractional shortening and stress-adjusted Vcfc comparable to each other but much lower than those of normal subjects (p less than or equal to 0.001). Patients treated with aspirin alone continued to have diminished fractional shortening and Vcfc compared with normal subjects in periods 2, 3, and 4 (all p less than or equal to 0.05). In contrast, fractional shortening and Vcfc in gamma-globulin-treated patients in these periods were comparable to those of normal subjects. By period 5, no difference was detected in systolic function or contractility between either treatment group and normal subjects. We conclude that early abnormalities of left ventricular contractility and myocardial function, as assessed by echocardiography, generally resolve by 1-3 years after disease onset and that recovery is accelerated by administration of IVGG in the acute phase.