Abstract 6075: Twenty-Five Year Outcome in Patients with Previous Myocardial Infarction Due to Coronary Artery Lesions Caused by Kawasaki Disease
The long-term prognosis in patients with previous myocardial infarction (MI) after Kawasaki disease (KD) is unknown. We investigated the outcome of 60 pts (45 male and 15 female) who had had MI due to coronary artery lesions caused by KD. The age at the initial MI ranged from 3 months to 33 years (median 2 years). The interval from the onset of KD to MI ranged from 16 days to 27 years (median 7 months), and the maximum follow-up period after MI was 32 years (median 15 years). Fifty-six pts after the initial MI underwent the selective coronary angiogram, the left ventriculogram by cardiac catheterization and the radioisotope myocardial perfusion imaging. The survival rate and the incidence of ventricular tachycardia (VT) after MI in the late period were analyzed by the Kaplan-Meier method. In this study, VT included non-sustained VT. Thirteen (22%) among the 60 pts died, and 3 among the 13 pts died of the initial MI. Twenty-five pts (42%) had had the thrombolysis therapy for acute MI, and the procedures had been effective in nine. Twenty-four pts (40%) underwent coronary artery bypass grafting after MI, and 3 pts had percutaneous coronary intervention (PCI). The 25-year survival rate after MI was 66%. In the late deaths, 5 pts (50%) among the 10 pts had unexpected sudden deaths. Two pts died of heart failure after MI, and 2 pts died after heart transplantation. Further, one had cardiac arrest during PCI. The incidence of VT and NSVT after MI at 25 years was 54%. Five among the 17 pts who had had either VT or NSVT died in the late period. One had implantable cardioverter defibrillator. The incidence of VT and NSVT in patients with the left ventricular ejection fraction (LVEF) less than 50% was significantly higher than that in patients with LVEF more than or equal to 50% (57%, n=35, versus 5%, n=21, p<0.01). Fifteen (88%) among the 17 pts with VT had had severe hypoperfusion area of the left ventricle, which implied non-viability myocardium in the radioisotope myocardial perfusion imaging. Severe myocardial damage of the left ventricle due to MI can induce VT in the late period, which influence on the prognosis in patients with previous MI strongly.