Use of the pacing pulmonary arterial catheter to detect endocardial electrical activity during hypothermic cardioplegic arrest.

The pacing Swan-Ganz catheter was evaluated for its ability to monitor atrial and ventricular electrical activity during cardioplegic arrest on cardiopulmonary bypass. This endocardial electrical activity was compared with the activity found on the standard electrocardiogram (ECG). The atrial electrodes detected activity that was noted also by visual inspection. The ventricular electrodes detected recurring electrical activity in 7 of 18 patients. Three of these 7 patients did not have simultaneous standard ECG activity, indicating that, in the usual monitoring circumstances, this ventricular electrical activity would not have been treated with repeat cardioplegia. If the pacing Swan-Ganz catheter is used for clinical care, it can be used also to monitor myocardial electrical activity during cardioplegic arrest.