Rhythm disturbances following rapid-deployment aortic valve replacement

OBJECTIVES: There have been reports of postoperative conduction disturbances after rapid-deployment aortic valve replacement. Our objective was to assess electrocardiogram changes in patients undergoing this procedure and review the literature on this topic. METHODS: In this retrospective case series, clinical data were extracted from patient records at St Vincent's Hospital Melbourne and the Australia New Zealand Society of Cardiac and Thoracic Surgeons database. Electrocardiogram data were obtained at baseline and postoperatively on day 5 and at week 6 and reviewed for rhythm disturbances and intracardiac conduction problems. Pacemaker status was also recorded. RESULTS: From 2013 to 2017, 100 consecutive patients underwent rapid-deployment aortic valve replacement with 1 valve type at our institution. Three patients were excluded because of paced rhythm preoperatively, leaving 97 patients (mean age 74.7 ± 8.12 years; 56.7% male) for analysis. Some 18.6% of patients developed new left bundle branch block at 5 days postoperatively and only 4.1% of patients found with persistent left bundle branch block at 6-week follow-up compared with preoperatively. No significant changes were observed in the frequencies of atrial fibrillation, first-degree heart block, and right bundle branch block. However, there was evidence of increases in paced rhythm and subsequent need for a permanent pacemaker. A total of 14 patients (14.4%) had a permanent pacemaker implanted at an average of 11.1 ± 2.9 days postoperatively. CONCLUSIONS: Rhythm disturbances and conduction abnormalities are noted with the rapid-deployment aortic valves used at our institution, but appear comparable to other rapid-deployment aortic valve replacement bioprostheses. These abnormalities may be related to the effect of the sub-annular stent frame of the valve system and implantation technique.