Experimental model of sudden cardiac death from unexplained cause.

To find a possible explanation for sudden cardiac death from unexplained cause, an experimental model was made with rabbits. The rabbits were fed an atherogenic diet for 2 and 4 months without precordial x-irradiation. Though the coronary sclerosis in the hearts of these rabbits was only slight or not detectable, the ventricular premature contraction threshold (VPCT) and the ventricular fibrillation threshold (VFT) decreased by about 50% and 60% of those in the control animals, respectively. The investigation of isozyme patterns of LDH, GOT, MDH and CPK in the hearts revealed that the changes of these isozyme patterns were almost identical with the results from the human hearts of sudden cardiac death from unexplained cause. From these results, the rabbits fed an atherogenic diet without precordial x-irradiation can be an experimental model of sudden cardiac death from unexplained cause.