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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
Temporal variation in optimal atrioventricular and interventricular delay during cardiac resynchronization therapy.
Maria Cristina Porciani1, Cristina Dondina, Roberto Macioce
1Division of Cardiology, Clinica Medica Careggi, Florence, Italy.
Journal of Cardiac Failure
|December 19, 2006
Summary
Optimal atrioventricular delay (AVd) and interventricular delay (VVd) settings for cardiac resynchronization therapy (CRT) need adjustment over time. Re-optimization is crucial for maintaining hemodynamic benefits in heart failure patients.
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Cardiac resynchronization therapy (CRT) utilizes tailored atrioventricular delay (AVd) and interventricular delay (VVd) to improve patient hemodynamics.
- The dynamic changes in optimal AVd-VVd combinations over time in CRT patients are not well understood.
Purpose of the Study:
- To investigate whether the optimal AVd-VVd combination in CRT patients changes over a 12-month period.
- To assess the impact of re-optimization on hemodynamic performance and clinical outcomes.
Main Methods:
- Twenty-two heart failure patients (NYHA class III, QRS > or = 130 ms) received biventricular devices.
- Myocardial performance index (MPI) was measured at baseline, 6, and 12 months to identify optimal AVd-VVd settings.
- Patients underwent re-optimization if MPI indicated suboptimal performance.
Main Results:
- The optimal AVd-VVd combination required re-optimization in 95% of patients within 6 months.
- Re-optimization significantly improved MPI compared to pre-re-optimization values.
- Clinical symptoms and left ventricular remodeling remained stable at 6 and 12 months post-initial optimization.
Conclusions:
- Optimal AVd and VVd settings are dynamic and change over time in CRT patients.
- While re-optimization improves MPI, sustained clinical benefits and reverse remodeling are not directly correlated with MPI changes over time.
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