Real-time analysis of conduction disturbances during TAVR with the CARA monitor.

BACKGROUND

The occurrence of conduction disturbances (CDs) remains the most frequent complication of transcatheter aortic valve replacement (TAVR). However, little is known about the timing of electrocardiogram (ECG) changes and CDs during the TAVR procedure.

OBJECTIVE

The objective of this study was to describe ECG changes throughout the TAVR procedure using the CARA monitor.

METHODS

This was a multicenter study including 196 prospectively enrolled patients without preexisting CDs undergoing TAVR. All patients were monitored with the CARA system, which uses a 12-lead ECG to measure PQ and QRS intervals, QRS axis, and variations with each heartbeat at every step: baseline, wire insertion, pre-dilatation, valve deployment, post-dilatation, and end of procedure.

RESULTS

PQ and QRS intervals progressively increased throughout the procedure, with a cumulative increase from 169.2 ± 20.0 ms to 186.0 ± 31.6 ms (P < .001) for the PQ interval and from 101.3 ± 10.5 ms to 126.0 ± 25.4 ms (P < .001) for the QRS interval, from baseline to the end of the procedure. A significant increase in the number of patients with left axis deviation was observed (7.7% at baseline vs 31.8% at end of procedure; P < .001). A total of 161 (82.1%) patients exhibited at least 1 CD episode (PQ >200 ms, QRS ≥120 ms, advanced heart block) during the procedure, with most episodes occurring during pre-dilatation and valve implantation maneuvers.

CONCLUSION

The CARA system facilitated real-time ECG monitoring, detecting subtle and progressive changes during TAVR. ECG changes occurred at each step, with most patients experiencing CDs, especially during pre-dilatation and valve implantation. The potential clinical impact of monitoring ECG dynamics and timing for early detection of severe CDs should be explored in future studies.