Heart with defibrillator transitioning to pacemaker

Downgrading Defibrillators: When Less is More for Heart Patients

Rhea Morgan in Health & Wellness November 2025 • 4 min read.

"Discover a novel approach to safely transition from a CRT-D to a CRT-P device, optimizing cardiac care and extending device lifespan."

As medical technology advances, the ability to tailor treatments to individual patient needs becomes increasingly crucial. One area where this is particularly evident is in the management of cardiac rhythm devices. Traditionally, patients with heart failure and a risk of sudden cardiac death are often implanted with a cardiac resynchronization therapy-defibrillator (CRT-D). These devices combine the functions of a pacemaker and a defibrillator, providing both rhythm support and protection against life-threatening arrhythmias.

However, as patients' conditions evolve, the need for the defibrillator function may diminish. For instance, some patients experience significant improvement in their heart function with CRT, reducing their risk of ventricular tachyarrhythmias. In such cases, continuing with a CRT-D may expose them to unnecessary risks, such as inappropriate shocks and complications associated with device replacements. The decision to replace or downgrade a CRT-D system upon reaching battery depletion requires careful consideration.

A recent study highlights a novel approach to address this challenge: downgrading a CRT-D to a CRT-P (cardiac resynchronization therapy-pacemaker) by utilizing the existing defibrillator lead in a pacemaker system. This method offers a less invasive and potentially safer alternative to complete device replacement, optimizing cardiac care while minimizing patient risk. This article delves into the details of this innovative technique, exploring its benefits, limitations, and implications for patients and healthcare providers.

The Case for Downgrading: Identifying Patients Who Benefit

Heart with defibrillator transitioning to pacemaker

The decision to downgrade from a CRT-D to a CRT-P is not one to be taken lightly. It requires a thorough evaluation of the patient's clinical history, current condition, and individual risk factors. Several factors may indicate that a patient is a good candidate for downgrading. One of the primary considerations is the absence of ventricular tachyarrhythmias. If a patient has not experienced any life-threatening arrhythmias since receiving their CRT-D, the need for the defibrillator function may be reassessed.

Another important factor is the improvement in left ventricular ejection fraction (LVEF). Studies have shown that a significant percentage of patients receiving CRT-Ds for primary prevention experience improvement in LV function. If a patient's LVEF normalizes or significantly improves, their risk of sudden cardiac death may be reduced, making a CRT-P a more appropriate option. The patient's age and overall health should also be taken into account. Older patients may be more susceptible to complications from device replacements, making a less invasive approach like downgrading particularly appealing. Patient preference also plays a crucial role in the decision-making process.

Absence of ventricular tachyarrhythmias
Improvement in left ventricular ejection fraction (LVEF)
Older age and frailty
Patient preference for reduced interventions

In a case study, an 86-year-old woman with a history of hypertension, atrial fibrillation, and coronary artery disease presented for replacement of her biventricular ICD due to battery depletion. Her initial CRT-D was implanted in 2012 due to left bundle branch block, nonischemic cardiomyopathy, and heart failure with a low LVEF of 25%. After CRT-D therapy, her LV function normalized, and she experienced no ventricular tachyarrhythmias. Given these factors, the decision was made to downgrade to a biventricular pacemaker.

The Future of Cardiac Device Management

The innovative approach of downgrading CRT-Ds to CRT-Ps using existing leads represents a significant step forward in cardiac device management. By carefully selecting patients and utilizing existing technology, healthcare providers can optimize patient outcomes, reduce unnecessary interventions, and extend the lifespan of implanted devices. As technology advances and our understanding of cardiac physiology deepens, expect even more personalized and tailored approaches to cardiac rhythm management, improving the lives of patients worldwide.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.hrcr.2018.09.006, Alternate LINK

Title: A Novel Method To Enable Biventricular Defibrillator To Biventricular Pacemaker Downgrade Involving Df4 Defibrillator Lead

Subject: Cardiology and Cardiovascular Medicine

Journal: HeartRhythm Case Reports

Publisher: Elsevier BV

Authors: Arnoldas Giedrimas, Brian Sisson, David Casavant

Published: 2018-12-01

Everything You Need To Know

What does it mean to downgrade from a CRT-D to a CRT-P, and what are the reasons for considering this procedure?

Downgrading from a CRT-D to a CRT-P involves replacing a device that combines a pacemaker and defibrillator with one that functions only as a pacemaker. This is done when the defibrillator function of the CRT-D is no longer deemed necessary, potentially reducing unnecessary risks such as inappropriate shocks and complications from device replacements. The procedure uses the existing defibrillator lead in a pacemaker system, making it less invasive than a complete device replacement. Patient selection is important to determine the right candidates.

What specific patient characteristics make someone a suitable candidate for downgrading from a CRT-D to a CRT-P?

Several factors make a patient a good candidate. These include the absence of ventricular tachyarrhythmias (life-threatening arrhythmias), improvement in left ventricular ejection fraction (LVEF), older age and frailty, and the patient's preference for reduced interventions. Absence of ventricular tachyarrhythmias indicates the defibrillator function may no longer be required. Improvement in LVEF suggests the risk of sudden cardiac death has decreased, and a CRT-P may be sufficient. Older patients may benefit from the less invasive approach of downgrading.

What are the main advantages of downgrading from a CRT-D to a CRT-P using the existing leads?

The primary benefits of downgrading a CRT-D to a CRT-P include optimizing patient outcomes, reducing unnecessary interventions, and potentially extending the lifespan of implanted devices. By avoiding unnecessary shocks, patients experience a better quality of life and reduced anxiety. The less invasive nature of the procedure can lead to fewer complications, particularly in older or frail patients. Utilizing existing leads, the approach is less invasive than replacing the entire system.

What information or data is missing from this discussion that would provide a more complete understanding of the implications of downgrading?

While the text describes a specific case study, it does not delve into the long-term outcomes of patients who have undergone this procedure. It would be valuable to know how these patients fare in the years following the downgrade in terms of overall survival, incidence of arrhythmias, and need for further interventions. More information on the specific protocols used for patient monitoring after the downgrade would also be beneficial.

What does downgrading from a CRT-D to a CRT-P signify about the future of cardiac device management, and what implications does it have for patients and healthcare providers?

Downgrading from a CRT-D to a CRT-P signifies a move towards personalized cardiac device management. As technology and understanding of cardiac physiology advance, we can expect more tailored approaches. This shift has implications for device manufacturers, healthcare providers, and patients, requiring a collaborative approach to optimize care. This includes the development of algorithms for patient selection, training for implanting physicians, and education for patients about the benefits and risks of different device options.