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Updated: Jul 30, 2026
A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
Implantable defibrillators for high-risk patients with heart failure who are awaiting cardiac transplantation
L A Saxon1, I Wiener, D B DeLurgio
1Department of Medicine, UCLA Medical Center 90024-1679, USA.
Insights
Implantable defibrillators are safe and effective for high-risk heart failure patients awaiting transplantation. These devices significantly reduce sudden cardiac death, offering excellent survival rates during the waiting period.
Area of Science:
- Cardiology
- Medical Devices
- Transplantation
Background:
- Sudden cardiac death is a primary cause of mortality in stable outpatients awaiting cardiac transplantation.
- The efficacy of implantable defibrillators in this specific patient group remains largely unestablished.
- Patients awaiting cardiac transplantation face a significant risk of mortality from sudden cardiac events.
Purpose of the Study:
- To evaluate the operative risks associated with implantable defibrillator implantation in heart failure patients awaiting transplantation.
- To determine the efficacy of implantable defibrillators in preventing sudden cardiac death in this high-risk population.
- To assess the rate of appropriate shocks and survival free from sudden death in patients receiving implantable defibrillators before cardiac transplantation.
Main Methods:
- A retrospective analysis was conducted on 15 high-risk patients accepted onto the outpatient cardiac transplant waiting list.
- Operative risk, time to appropriate shock, and incidence of sudden death were analyzed.
- Comparison of outcomes between epicardial and transvenous lead systems was performed.
Main Results:
- Implantable defibrillator placement demonstrated low operative risk, with no major complications in transvenous lead systems.
- Sudden death-free survival until transplantation was excellent at 93%.
- 60% of patients received at least one appropriate shock, indicating device efficacy in managing arrhythmias.
Conclusions:
- Implantable defibrillators are a viable option for selected high-risk heart failure patients awaiting cardiac transplantation.
- The procedure carries a low operative risk, and effective defibrillation energies can be achieved.
- The therapy significantly improves survival by preventing sudden cardiac death during the pre-transplant waiting period.
Abstract:
The objective of this study was to assess the operative risk and efficacy of implantable defibrillators for preventing sudden death in patients with heart failure awaiting transplantation. The average waiting time for elective cardiac transplantation is 6 months to 1 year. Sudden cardiac death is the major source of mortality in outpatients in stable condition awaiting cardiac transplantation. The efficacy of implantable defibrillator therapy in this population is not established. We analyzed the operative risk, time to appropriate shock, and sudden death in 15 patients determined to be at high risk of sudden death who were accepted onto the outpatient cardiac transplant waiting list. Nonfatal postoperative complications occurred in two (13%) subjects with epicardial defibrillating lead systems and in none with transvenous lead systems. Defibrillation energies were 16 +/- 2 J versus 24 +/- 2 J with epicardial and transvenous lead systems, respectively. Sudden death free survival until transplantation was 93%. Most of the patients (60%) had an appropriate shock during a mean follow-up of 11 +/- 12 months. The mean time to an appropriate shock was 3 +/- 3 months. Hospital readmission was required in three (20%) subjects to await transplantation on an urgent basis. However, two of these subjects had received appropriate shocks before readmission. In selected patients at high risk for sudden death while on the outpatient cardiac transplant waiting list, the operative risk is low and adequate defibrillation energies can be obtained to allow implantable defibrillator placement. Most subjects will have an appropriate shock as outpatients before transplantation, and sudden death free survival is excellent.(ABSTRACT TRUNCATED AT 250 WORDS)
