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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Insights from a cardiac resynchronization optimization clinic as part of a heart failure disease management program
Wilfried Mullens1, Richard A Grimm, Tanya Verga
1Department of Cardiovascular Medicine, Cleveland, Ohio 44195, USA.
Insights
A protocol-driven evaluation is feasible for cardiac resynchronization therapy (CRT) patients with poor response. Optimizing CRT settings and therapies after multidisciplinary assessment can reduce adverse events.
Area of Science:
- Cardiology
- Heart Failure Management
- Medical Device Optimization
Background:
- Up to 33% of advanced heart failure patients do not respond to cardiac resynchronization therapy (CRT).
- Identifying reasons for CRT non-response is crucial for improving patient outcomes.
Purpose of the Study:
- To assess the feasibility and value of a systematic, protocol-driven evaluation for CRT non-responders.
- To identify common causes of suboptimal CRT response in advanced heart failure patients.
Main Methods:
- A cohort of 75 ambulatory patients with advanced heart failure and CRT >6 months underwent a comprehensive protocol-driven evaluation.
- Evaluations focused on identifying reasons for suboptimal CRT response, including device settings, medical treatment, arrhythmias, lead position, and baseline dyssynchrony.
Main Results:
- Most patients had identifiable reasons for suboptimal response, with inadequate device settings (47%) being the most common.
- Multidisciplinary recommendations led to therapy modifications in 74% of patients.
- Patients receiving recommendations experienced significantly fewer adverse events (13% vs. 50%).
Conclusions:
- A routine protocol-driven approach is feasible for evaluating CRT non-responders.
- Multidisciplinary evaluation and subsequent therapy adjustments may reduce adverse events in CRT patients.
Objectives:
Our aim was to determine the feasibility and value of a protocol-driven approach to patients with cardiac resynchronization therapy (CRT) who did not exhibit a positive response long after implant.
Background:
Up to one-third of patients with advanced heart failure do not exhibit a positive response to CRT.
Methods:
A total of 75 consecutive ambulatory patients with persistent advanced heart failure symptoms and/or adverse reverse remodeling and CRT implanted >6 months underwent a comprehensive protocol-driven evaluation to determine the potential reasons for a suboptimal response. Recommendations were made to maximize the potential of CRT, and adverse events were documented.
Results:
All patients (mean left ventricular [LV] ejection fraction 23 +/- 9%, LV end-diastolic volume 275 +/- 127 ml) underwent evaluation. Eighty-eight percent of patients had significantly better echocardiographic indexes of LV filling and LV ejection with optimal setting of their CRT compared with a temporary VVI back-up setting. Most patients had identifiable reasons for suboptimal response, including inadequate device settings (47%), suboptimal medical treatment (32%), arrhythmias (32%), inappropriate lead position (21%), or lack of baseline dyssynchrony (9%). Multidisciplinary recommendations led to changes in device settings and/or other therapy modifications in 74% of patients and were associated with fewer adverse events (13% vs. 50%, odds ratio: 0.2 [95% confidence interval: 0.07 to 0.56], p = 0.002) compared with those in which no recommendation could be made.
Conclusions:
Routine protocol-driven approach to evaluate ambulatory CRT patients who did not exhibit a positive response is feasible, and changes in device settings and/or other therapies after multidisciplinary evaluation may be associated with fewer adverse events.
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