Conduction disturbances common after new-generation self-expanding valve implantation

Implantation with new-generation, self-expanding aortic valves appears to result in a significant spike in the rates of high-degree cardiac conduction disturbance (HDCD), such as an increase in PR and QRS intervals, reports a new study.

The study included 344 consecutive patients who underwent transcatheter aortic valve replacement (TAVR) for severe aortic stenosis, all of whom received new-generation self-expandable valves. Electrocardiography parameters were assessed at baseline, before discharge, and after TAVR.

Immediately post-TAVR, researchers detected a large increase in PR interval (169.9 to 188.04 ms) and QRS complex width (101.7 to 129.55 ms) as compared with baseline values. This was followed by a partial in-hospital recovery (PR to 179.4 ms, QRS to 123.06 ms).

The net result was that by hospital discharge, both PR interval and QRS complex width saw a slight but significant increase from baseline, with respective change values of 12.6 and 21.4 ms (p<0.001 for both).

Overall, the global incidence rate of new-onset persistent HDCD was 46.3 percent at hospital discharge, with 17.7 percent of patients needing permanent pacemaker implants.

Valve recapture (odds ratio [OR], 2.8, 95 percent confidence interval [CI], 1.1–7.2; p=0.033) and an implantation depth ≥6 mm (OR, 1.9, 95 percent CI, 1.1–3.3; p=0.015) were significant risk factors for HDCD at discharge. Meanwhile, implantation depth <3

mm appeared to be significantly protective (OR, 0.3, 95 percent CI, 0.1–0.7; p=0.014).

“New generation self-expanding valves were associated with a significant increase in PR and QRS interval at hospital discharge leading to a very high rate of HDCD,” the researchers said.

“These results should be validated in a large-scale prospective study to corroborate their predictive capacity,” they added.