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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
Cardiac resynchronization therapy in patients with mildly impaired left ventricular function
Paul W X Foley1, Berthold Stegemann, Russell E A Smith
1University of Birmingham, Department of Cardiology, Good Hope Hospital, Heart of England NHS Trust, Sutton Coldfield, United Kingdom.
Pacing and Clinical Electrophysiology : PACE
|March 3, 2009
Summary
Cardiac resynchronization therapy (CRT) benefits patients with left ventricular ejection fraction (LVEF) >35%, not just those with LVEF ≤35%. This study shows CRT improves outcomes and symptoms in this expanded patient group.
Area of Science:
- Cardiology
- Medical Devices
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) is standard for heart failure with reduced ejection fraction.
- Echocardiography (Echo) may underestimate left ventricular ejection fraction (LVEF), potentially excluding eligible patients.
Purpose of the Study:
- To evaluate the effects of CRT in patients with LVEF >35% initially misclassified by Echo.
- To compare outcomes between patients with LVEF ≤35% and LVEF >35% (based on CMR).
Main Methods:
- 157 patients with NYHA class III/IV and QRS duration ≥120 ms undergoing CRT were analyzed.
- Patients were divided into Group A (CMR-LVEF ≤35%) and Group B (CMR-LVEF >35%).
- Clinical evaluations, including 6-minute walk tests and quality of life questionnaires, were performed at baseline and post-CRT.
Main Results:
- Both groups showed similar improvements in NYHA class, quality of life, and 6-minute walking distance.
- Symptomatic response rates were high in both groups (79% in Group A, 92% in Group B).
- Group A (LVEF ≤35%) had a higher risk of all-cause death, cardiovascular events, and cardiovascular death compared to Group B (LVEF >35%).
Conclusions:
- The benefits of CRT extend to patients with LVEF >35% who may be identified by CMR.
- This suggests a broader potential patient population for CRT.
- Accurate LVEF assessment is crucial for optimal patient selection for CRT.
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