Clinical trial NCT05557006: Change of QRS Morphology and Electrophysiological Characteristics During Pacing Within the Interventricular Septum
Official title: Change of QRS Morphology and Electrophysiological Characteristics During Pacing Within the Interventricular Septum: a Prospective, Observational Study
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Cardiac Pacing
Keywords: Left Bundle Branch Pacing
Left Bundle Branch Area Pacing
Septal Pacing
Left Ventricular Activation Time
Right Ventricular Activation Time
Lead sponsor: General Hospital of Shenyang Military Region
Sponsor class: OTHER
First posted: 2022-09-27
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Patients requiring a high percentage of ventricular pacing (\>40% expected ventricular pacing) include patients with advanced or third-degree atrioventricular block and atrial fibrillation with bradycardia.

Brief summary: Conduction system pacing (CSP), including His bundle pacing (HBP) and left bundle branch (LBB) pacing (LBBP), as a physiological pacing strategy, can achieve interventricular and/or intra-left ventricular mechanical synchronization by delivering physiological or nearly physiological ventricular activation. And many studies have verifed clinical efficacy of CSP that it can significantly relieve dyssynchrony of ventricular contraction, improve cardiac function and reduce the risk of heart failure as compared to right ventricular pacing. However, CSP has some shortcomings which limit its widespread application to some extent. As for HBP, although it can achieve optimal physiological ventricular synchronization, the problems of relatively high pacing threshold, low R-wave amplitude, the long-term performance, and inability to correct infra-Hisian atrioventricular block and intraventricular block in some patients have always been concerns. Nevertheless, LBBP is likely free of the restrictions mentioned above. On the contrary, LBBP can capture the left conduction system by directly stimulating the proximal LBB distal to the site of conduction block, thereby achieving rapid and physiological LV activation with a lower and stable pacing threshold and higher R-wave amplitude. However, as a newly emerged physiologic pacing technology, LBBP is currently in the exploratory stage and there are some phenomena to be interpreted, such as the evolution of pacing QRS morphology during the lead penetration into the interventricular septum. Therefore, the aim of this study is to assess the morphological evolution and electrophysiological characteristics of various pacing QRS patterns observed as the lead penetrates the interventricular septum from right to left.


Eligibility criteria: Inclusion Criteria:

* The indications for pacemaker implantation are in accordance with the 2021 European Society of Cardiology (ESC) guidelines.
* Patients requiring a high percentage of ventricular pacing (\>40% expected ventricular pacing) include patients with advanced or third-degree atrioventricular block and atrial fibrillation with bradycardia.
* Left bundle branch pacing will be performed.
* Patients voluntarily participate and sign informed consent.

Exclusion Criteria:

* Atrioventricular block caused by reversible factors such as acute myocardial infarction and electrolyte disturbance.
* Patients with severe liver or renal failure.
* Life expectancy \< 1 year.
* Patients with age \< 18 years.
* Left ventricular ejection fraction (LVEF) \< 40%.

Primary outcomes:
measure: Left ventricular activation time (LVAT)
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
measure: Right ventricular activation time (RVAT)
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
measure: Paced QRS morphology
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
Secondary outcomes:
measure: Stimulus-QRSend duration (s-QRSend)
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
measure: The late-R wave duration and amplitude in lead V1 (r´dur、r´amp)
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
measure: The S wave duration and amplitude in lead V6 (Sdur、Samp)
timeFrame: Continuous uninterrupted monitoring during the lead penetration into the interventricular septum.
Other outcomes:
Locations:
city: Shenyang
country: China
facility: General Hospital of Northern Theater Command
state: Liaoning
Study officials:
affiliation: The General Hospital of Northern Theater Command
name: Yanchun Liang, MD、PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Shimeno K, Tamura S, Nakatsuji K, Hayashi Y, Abe Y, Naruko T. Characteristics and proposed mechanisms of QRS morphology observed during the left bundle branch pacing procedure. Pacing Clin Electrophysiol. 2021 Dec;44(12):1987-1994. doi: 10.1111/pace.14382. Epub 2021 Oct 31.
citation: Zhang J, Sheng X, Pan Y, Wang M, Fu G. Electrophysiological Insights into Three Modalities of Left Bundle Branch Area Pacing in Patients Indicated for Pacing Therapy. Int Heart J. 2021 Jan 30;62(1):78-86. doi: 10.1536/ihj.20-490. Epub 2020 Dec 26.