Purpose: Controlled hypothermia of the right atrium has been shown to reduce postoperative atrial fibrillation after on-pump coronary artery bypass grafting. A device has been developed that couples right atrial and nodal cooling with modified dual-stage venous drainage by circulating cold sterile saline through an intracavity, shape-memory balloon.
Description: The atrial cooling device was used in 41 patients undergoing elective coronary artery bypass grafting. Systemic temperatures were held at 36 degrees C, and temperatures of atrial structures were reduced to about 19 degrees to 20 degrees C at 30 minutes.
Evaluation: Electrical activity was effectively suppressed during cross-clamp by controlled cooling of the right atrium. Hemodilution was reduced by right atrial isolation and collection of crystalloid cardioplegia. Cardiac electrical activity returned without sustained arrhythmias in all patients. Postoperative atrial fibrillation developed in only 3 of the 38 patients.
Conclusions: The results indicate that local atrial cooling may contribute to protection of the right atrium, subsequently reducing the incidence of transient postoperative atrial fibrillation.