Sequential versus simultaneous biventricular resynchronization for severe heart failure: evaluation by tissue Doppler
Peter Sogaard1, Henrik Egeblad, Anders K Pedersen
1Department of Cardiology, Aarhus University Hospital, Skejby Sygehus, Aarhus, Denmark. psogaard@dadlnet.dk
Insights
Sequential cardiac resynchronization therapy (CRT) significantly enhances heart function by optimizing biventricular pacing delays. This approach improves both systolic and diastolic performance in heart failure patients.
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Cardiac resynchronization therapy (CRT) with biventricular pacing improves heart failure outcomes.
- Simultaneous pacing is standard, but optimal timing remains debated.
Purpose of the Study:
- To evaluate sequential CRT using tissue tracking and 3D echocardiography.
- To determine the impact of individualized interventricular delay programming on cardiac performance.
Main Methods:
- Twenty patients with heart failure and bundle-branch block underwent CRT.
- Tissue tracking and 3D echocardiography assessed myocardial contraction before and after pacing.
- Multiple interventricular delays were tested to find optimal sequential programming.
Main Results:
- Sequential CRT significantly reduced delayed longitudinal contraction (DLC) and increased left ventricular ejection fraction (LVEF%).
- Optimal sequential CRT further improved DLC and LVEF% compared to simultaneous CRT.
- Three-month follow-up showed sustained improvements in LVEF% with sequential CRT.
- Sequential CRT increased diastolic filling time by 7%.
Conclusions:
- Sequential CRT offers significant advantages over simultaneous CRT for both systolic and diastolic performance.
- Tissue tracking is effective for optimizing interventricular delay in CRT.
Background:
Cardiac resynchronization therapy (CRT) by means of simultaneous biventricular pacing improves left ventricular systolic performance and synchrony in patients with heart failure and bundle-branch block. We used tissue tracking and 3D echocardiography to evaluate the impact of sequential CRT with individualized interventricular delay programming.
Methods And Results:
Twenty consecutive patients with severe heart failure and left bundle-branch block were included. Tissue tracking and 3D echocardiography were carried out before and on the day after pacemaker implantation. Eleven different interventricular delays were examined in each patient. Patients were reexamined after 3 months. Simultaneous CRT immediately reduced the extent of myocardium displaying delayed longitudinal contraction (DLC) from 48.6+/-16% to 23.2+/-13% (P<0.01) and increased left ventricular ejection fraction percentage (LVEF%) from 22.4+/-6% to 29.7+/-5% (P<0.01). However, optimum sequential CRT caused a further reduction in the extent of DLC from 23.2+/-13% to 11.1+/-7.2% (P<0.01), with a simultaneous increase in LVEF% (from 29.7+/-5% to 33.9+/-6%, P<0.01). Three months of optimum sequential CRT further improved LVEF% (from 33.6+/-6% to 38.6+/-7.2%, P<0.01). Tissue tracking detected the segments with DLC, and their location determined optimum interventricular delay programming. Compared with simultaneous CRT, sequential CRT increased diastolic filling time by 7+/-2.5%.
Conclusions:
Compared with simultaneous CRT, sequential CRT significantly improves left ventricular systolic and diastolic performance. Tissue tracking can be used to select optimum interventricular delay during CRT.
More Related Videos
12:45Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
10:17Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
Published on: April 11, 2025
Related Concept Videos
01:30Heart Failure IV: Classification and Diagnostic Evaluation
01:30Cardiomyopathy II: Dilated Cardiomyopathy