Feasibility of His bundle pacing facilitated by EASI derived 12­lead ECG.

INTRODUCTION: His bundle pacing (HBP) has become popular in recent years as a more physiological alternative to conventional right ventricular pacing. Implantation requires 12­lead ECG during surgery, which is not readily available in a standard operating room. Often but not always HBP is performed in an electrophysiology lab. EASI is a reduced lead system which enables derived 12­lead ECG. EASI derived 12­lead ECGs on modern tablet computers offer a more mobile and lightweight ECG solution which does not obstruct fluoroscopy during implantation. This case series aims to compare standard 12­lead ECG to EASI derived 12­lead ECG in patients undergoing HBP implantation. METHODS AND RESULTS: A total of 11 patients received permanent HBP guided only by fluoroscopy, a pacing system analyzer (Medtronic CareLink SmartSync Device Manager) and EASI derived 12­lead ECG (CardioSecur Pro). During the first postoperative device interrogation HBP criteria, as defined in the EHRA consensus paper on conduction system pacing, were evaluated with the EASI derived system as well as a standard 12­lead ECG and compared to each other. There was perfect agreement with regards to these criteria which lead to identical conclusions in all cases. CONCLUSION: HBP implantation can be performed with EASI derived 12­lead ECG instead of conventional 12­lead ECG. Criteria for discriminating between selective His bundle, non-selective His bundle or myocardial capture alone are clearly visible in the EASI derived ECG leading to the same conclusion when compared to standard 12­lead ECG. Compared to a conventional 12­lead ECG the EASI system offers a leaner setup with less visual obstruction on fluoroscopy.

Smartphone-derived multichannel electrocardiogram for exercise stress testing.

INTRODUCTION: The use of mobile devices for electrocardiogram (ECG) recording and the ability to use this technology to immediately review dynamic waveforms is growing tremendously. While over-the-counter ECG devices may display rhythm disorders and ST-segment changes at rest, changes during physical exercise have thus far not been evaluated. We compared a mobile device (smartphone/tablet)-enabled vectorial 4-electrode ECG system (SPE) with the current standard 12­lead (STE) ECG both at rest and during exercise. METHODS AND RESULTS: A total of 428 patients underwent simultaneous ECG testing with both technologies during rest and maximal exercise. The vectorial ECG was displayed as 12­lead ECG, and diagnostic accuracy and ECG quality (independently judged by blinded cardiologists) were compared with the current standard. Signal quality was good with both ECG technologies. At rest, there was excellent agreement between SPE and STE regarding rhythm (98%), AV-conduction (97%), wave duration (90%), and electrical axis (88-97%). During exercise the presence or absence of ST-deviation (>0.1 mm) corresponded in 90% of cases with no statistically significant difference. The positive predictive value was 48.5% and the negative predictive value was 94%. For ST-deviations >0.2 mm the percentage match was 97% during exercise. For rhythm disorders and for intraventricular conduction (left- and right-bundle branch block detection) it was >90%. CONCLUSION: A smart-device-enabled vectorial ECGs system using the CardioSecur system can be used in daily practice to reliably interpret an ECG at rest and during physical exercise, although it is less accurate with respect to the detection of ST-deviation.