Atrioventricular nodal parasystole

Ten cases of atrioventricular nodal parasystole have been discussed in detail. The variation of the shortest interectopic intervals was noted to be much greater than anticipated. The atrioventricular nodal parasystolic rate was somewhat slower than would be expected in view of the physiologic automaticity of the atrioventricular node; this finding is similar to the experiences reported by other clinicians. The youngest patient in our series (38 years) had the most diseased heart which weighed 830 gm. at autopsy. Two patients did not show evidence of heart disease or cardiomegaly. One patient (Case 7) had marked electrolyte imbalance which presumably produced the parasystole.