ENHANCE-Efficacy of the Presence of Right Ventricular Apical Pacing Induced Ventricular Dyssynchrony as a Guiding Parameter for Biventricular Pacing in Patients With Bradycardia and Normal Ejection Fraction

Not Applicable

Completed

Conditions: Bradycardia

Interventions: Device: CRT-P OFF
Device: CRT-P ON
Device: DDDR

Registration Number: NCT01559311

Lead Sponsor: Abbott Medical Devices

Brief Summary: The purpose of this clinical project is to evaluate the efficacy of the presence of Right Ventricular Apical (RVA) pacing induced ventricular dyssynchrony as a guiding parameter for bi-ventricular pacing in patients with bradycardia and normal left ventricular ejection fraction (LVEF). The results of this project may provide with the evidence based medicine for guidelines expansion of using Cardiac resynchronization therapy (CRT) in patients with Heart Block and normal LVEF (LVEF \>45%).

Detailed Description: All eligible patients willing to provide written informed consent were invited to participate in the study, and then randomized 1:2 to either the Control Group or Echo-guided Group. Patients randomized into the Control Group were implanted with a dual chamber pacemaker (DDDR) device (St. Jude Medical) standard therapy. Patients randomized into the Echo-guided Group were implanted with a cardiac resynchronization therapy pacemaker (CRT-P) device (St. Jude Medical), which was programmed to DDDR pacing mode (CRT-P OFF) at implant. For each Echo-guided Group patient, presence of RVA pacing induced ventricular dyssynchrony was assessed within 24-hour of implant using the standardized criteria of Doppler echocardiography. The Echocardiography Core Laboratory (Echo Core Lab) then analyzed each image and the treatment allocation of the Echo-guided Group was done within 72-hour post implant based on the Echo Core Lab outcomes:

* Patients with the presence of RVA pacing induced ventricular dyssynchrony were allocated to the CRT-P standard therapy with CRT-P turned ON

* Patients with the absence of RVA pacing induced ventricular dyssynchrony were allocated to the DDDR standard therapy with CRT-P remained OFF

Patients meeting all the inclusion criteria and not meeting any of the exclusion criteria were eligible for the study. Data was collected at the following study visits:Enrollment, Implant \& Randomization, Pre-discharge (PDH) (≤ 72 hours post implant), Month 1 follow-up visit: 30 ± 14 days post implant, Month 3 follow-up visit: 90 ± 14 days post implant, Month 6 follow-up visit: 180 ± 14 days post implant and Month 12 follow-up visit: 365 ± 14 days post implant

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 98

Inclusion Criteria

Patient meets current indications for implantation of a DDDR pacemaker
Patient is geographically stable and willing to comply with the required follow-up schedule
Patient has LVEF >45%
Patient has atrioventricular block (IIo or above)
Patient has adequate echocardiographic images to measure LV volumes and LVEF

Exclusion Criteria

Patient has permanent atrial fibrillation (AF)
Patient has unstable angina or an acute coronary syndrome
Patient has undergone percutaneous coronary intervention or coronary artery bypass surgery within the previous 3 months
Patient's life expectancy is less than 1 year
Patient is less than 18 years old
Patient is pregnant
Patient has received a heart transplant

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
CRT-P OFF	CRT-P OFF	Patients randomized into the Echo-guided Group were implanted with a CRT-P device (St. Jude Medical), which was programmed to DDDR pacing mode (CRT-P OFF) at implant. For each Echo-guided Group patient, presence of RVA pacing induced ventricular dyssynchrony was assessed within 24-hour of implant using the standardized criteria of Doppler echocardiography. The Echocardiography Core Laboratory (Echo Core Lab) then analyzed each image and the treatment allocation of the Echo-guided Group was done within 72-hour post implant based on the Echo Core Lab outcomes: • Patients with the absence of RVA pacing induced ventricular dyssynchrony were allocated to the DDDR standard therapy with CRT-P remained OFF
CRT-P ON	CRT-P ON	Patients randomized into the Echo-guided Group were implanted with a CRT-P device (St. Jude Medical), which was programmed to DDDR pacing mode (CRT-P OFF) at implant. For each Echo-guided Group patient, presence of RVA pacing induced ventricular dyssynchrony was assessed within 24-hour of implant using the standardized criteria of Doppler echocardiography. The Echocardiography Core Laboratory (Echo Core Lab) then analyzed each image and the treatment allocation of the Echo-guided Group was done within 72-hour post implant based on the Echo Core Lab outcomes: • Patients with the presence of RVA pacing induced ventricular dyssynchrony were allocated to the CRT-P standard therapy with CRT-P turned ON
DDDR	DDDR	Patients randomized into the Control Group were implanted with a DDDR device (St. Jude Medical) standard therapy.

Primary Outcome Measures

Name	Time	Method
LVEF	12 months	Left Ventricular Ejection Fraction (LVEF) for assessment of Left ventricular (LV) systolic function
LVESV	12 months	Left ventricular end-systolic volume (LVESV) for assessment of LV remodeling

Secondary Outcome Measures

Name	Time	Method

Trial Locations

Locations (7): Madras Medical Mission
🇮🇳
Chennai, India
All India Institute of Medical Sciences
🇮🇳
New Delhi, India
The Prince Charles Hospital
🇦🇺
Chermside, Australia
Istituto Clinico Humanitas
🇮🇹
Rozzano, Italy
Prince of Wales Hospital
🇨🇳
Hong Kong, China
CARE Banjara
🇮🇳
Hyderabad, India
Siriraj Hospital
🇹🇭
Bangkok, Thailand