PreFER Managed Ventricular Pacing (MVP) For Elective Replacement

• Time to first event of cardiovascular hospitalization [ Time Frame: >2 years follow-up ]
  

• Demonstrate that fewer patients experience atrial tachycardia/atrial fibrillation (AT/AF) with MVP programmed ON compared to patients with MVP OFF and common device programming [ Time Frame: >2 years follow-up ]
  
• Compare the percentage ventricular pacing in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the change in New York Heart Association (NYHA) functional class over time [ Time Frame: >2 years follow-up ]
  
• Compare the change in use of anticoagulation in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the change in the use of cardiovascular medication over time in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the incidence of high voltage therapies in both groups [ Time Frame: >2 years follow-up ]
  
• Compare the hazard rate for all cause mortality in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the hazard rate for stroke in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the hazard rate for amount and duration of cardiovascular related hospitalization in both arms [ Time Frame: >2 years follow-up ]
  
• Evaluate incidence of Class I pacemaker indication in ICD patients in both arms [ Time Frame: >2 years follow-up ]
  
• Compare patient symptoms in both arms [ Time Frame: >2 years follow-up ]
  
• Compare the percentage atrial pacing in both arms [ Time Frame: >2 years follow-up ]
  
• Evaluate health economics in both arms [ Time Frame: >2 years follow-up ]
  

A number of clinical studies (Danish I1,2, Danish II3,4, David5,27, MOST6) over the past few years have shown that, in patients with intact AV conduction, unnecessary chronic right ventricular (RV) pacing can cause a variety of detrimental effects, including atrial fibrillation (AF), left ventricular (LV) dysfunction, and congestive heart failure (CHF). These effects are believed to result from the mechanical dyssynchrony and ventricular chamber dysfunction that occurs with chronic, single-site, apical ventricular stimulation.

Therefore a new pacing modality, Managed Ventricular Pacing (MVP), was designed to give preference to natural heart activity by minimizing unnecessary right ventricular pacing. This is accomplished by automatically switching between single chamber atrial and dual-chamber pacing based on specific patient needs.

MVP is an atrial-based dual-chamber pacing mode that provides functional AAI/R pacing with ventricular monitoring and back-up DDD/R pacing only as needed during episodes of AV block.

The reversibility of the detrimental effects caused by ventricular pacing has been initially investigated in small patient populations with short pacing durations in AAI3, 13 and needs further investigation.