Postoperative atrial fibrillation (AF) after coronary artery bypass grafting (CABG) may occur in as many as 30% of cases. Medical management of this problem is often ineffective. While the etiology for postoperative AF remains unclear, increased cardiac sympathetic nervous activity is a likely factor. Previous animal studies have shown that TMR with a Holmium:YAG laser can sympathectomize the regional myocardium. The purpose of this study is to examine the effect of TMR on the incidence of postoperative AF.
Fourteen U.S. centers participated in a nonrandomized study during the period from January 1, 2002 to March 31, 2005. Patients with diffuse multi –small vessel coronary artery disease (CAD) who could not be completely revascularized by CABG alone compromise the study population. Patients were followed in-hospital and through 30 days.
A total of 739 (men 72%) patients with a mean age of 64±11 years and a mean ejection fraction of 51%±10% underwent CABG + TMR. Among comorbidities (hyperlipidemia:83%; hypertension:78%; prior myocardial infarction:36%; smoking:59%), only diabetes (47%) occurred more frequently compared to the Society of Thoracic Surgeons (STS) database for primary CABG (p<0.05). An on pump technique was used in 643 (87%) operations. Patients received an average of 3.0±1.1 bypass grafts and 22±9 TMR channels. At 30 days, all-cause mortality was 2.4%. The incidence of postoperative AF was 5.3%, and significantly lower (p<0.001) than that reported for CABG alone in a multicenter (32%) experience.
Postoperative AF in the CABG patient increases CVA risk, length of stay and complicates patient management. While TMR has proven itself valuable in angina reduction for patients with diffuse CAD it’s effect on postoperative AF has not been previously described. Study patients undergoing CABG + TMR demonstrated a significantly lower incidence of postoperative AF compared to historical controls. This striking difference warrants further investigation.
TMR with a Holmium:YAG laser may have a place in the prevention of AF in the post CABG patient.
Gary Allen, None.