Safety and the Effects of Isolated Left Ventricular Pacing in Patients With Bradyarrhythmias

Study Overview
=================
Brief Summary
-----------------
Previous experimental and clinical studies have consistently suggested that right ventricular (RV) apical pacing has important adverse effects. Ventricular pacing, however, is required, and cannot be reduced in many patients with atrioventricular block. The SAFE-LVPACE study is a randomized controlled trial that compare the effects of conventional right ventricular (RV) pacing vs. left ventricular (LV) in patients with AV block.

Detailed Description
-----------------
Over the past several years, there has been growing concern over the significant deleterious effects of RV pacing, including electromechanical dyssynchrony, proarrhythmia and development of heart failure (HF). However, it remains unclear whether pacing-related ventricular dyssynchrony can translate into significant LV structural changes and produce important clinical impairment in an average pacemaker population with compromised AV conduction. Alternatively, left ventricular pacing has been shown to minimize ventricular dyssynchrony and to improve symptoms and prognosis in patients with mild to moderated systolic HF and prolonged QRS duration. This randomized controlled study is been conducted to compare the effects of conventional right ventricular (RV) pacing vs. left ventricular (LV) in patients with AV block. The hypothesis is that isolated LV pacing through the coronary sinus can be used safely and provide greater hemodynamic benefits to patients with AV block and normal ventricular function who require only the correction of heart rate. Specifically, the investigator aims are to evaluate the safety, efficacy and the effects of left ventricular pacing using active-fixation coronary sinus lead-the Attain StarFix® Model 4195 OTW Lead, compared to right ventricular pacing in patients with implantation criteria for conventional pacemaker stimulation.

Official Title
-----------------
Randomized Clinical Study to Assess the Safety and the Effects of Isolated Left Ventricular Pacing in Patients With Bradyarrhythmias

Conditions
-----------------
Bradyarrhythmias, Arrhythmias, Atrioventricular Block, Ventricular Dysfunction, Cardiovascular Disease

Intervention / Treatment
-----------------
* Device: Left ventricular pacing through coronary sinus tributaries (Attain StarFix)
* Device: Right ventricular pacing (Medtronic)


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Older than 18 years Pacemaker initial implant by transvenous approach Presence of AV block Presence of atrial fibrillation / atrial flutter with slow ventricular response Left ventricular systolic function > 0.40 Subject agreed to participate and signed the consent form Exclusion Criteria: Absence of venous access Impediment of venous access due to presence of intracardiac defects Impediment of venous access due to presence of tricuspid valve prosthesis Need for radiotherapy in the chest Presence of chest deformity Pregnancy Life expectancy of less than one year Contraindication to administration of iodinated contrast (creatinine > 3.0) Unable to attend the follow-up appointments

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: RV Pacing<br>Right ventricular pacing | Device: Right ventricular pacing (Medtronic)<br>* Conventional right ventricular pacing in patients with bradycardia.<br>* Other names: Right ventricular lead Medtronic 5076-58;|
| Experimental: LV Pacing<br>Left ventricular pacing through coronary sinus tributaries | Device: Left ventricular pacing through coronary sinus tributaries (Attain StarFix)<br>* Left ventricular pacing in patients with bradycardia<br>* Other names: Attain StarFix® Model 4195 OTW Lead;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical success | Surgical success: absence of complications | Participants will be evaluated during the perioperative period and during the hospital stay, an expected average of 2 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Echocardiographic and Clinical composite | Echocardiographic: ventricular dysfunction Clinical composite: all mortality, cardiovascular mortality, hospitalization, heart failure | Participants will be evaluated at 6 and 24 months after PM implantation | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Pacemaker implantation, Coronary sinus, Ventricular dysfunction, Right ventricular pacing, Left ventricular pacing, Pacemaker