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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
Electrical optimization of cardiac resynchronization in chronic heart failure is associated with improved clinical
Christopher Adlbrecht1, Martin Hülsmann, Marianne Gwechenberger
1Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
Insights
Optimizing cardiac resynchronization therapy (CRT) with echocardiographic AV-interval evaluation improves clinical outcomes in heart failure patients. This study highlights the importance of proper device settings for better patient management and reduced hospitalizations.
Area of Science:
- Cardiology
- Biomedical Engineering
- Clinical Medicine
Background:
- Cardiac resynchronization therapy (CRT) is a treatment for chronic heart failure (CHF), but patient response varies.
- Inadequate device settings, particularly atrioventricular (AV) delay, may explain suboptimal outcomes.
- Echocardiographic evaluation of AV delay is underutilized in routine CRT practice.
Purpose of the Study:
- To investigate the impact of echocardiographic AV-interval evaluation on long-term clinical outcomes in CHF patients receiving CRT.
- To identify factors associated with improved or worsened clinical outcomes in CRT patients.
Main Methods:
- Retrospective observational study of 205 CHF patients undergoing CRT.
- Analysis of long-term clinical outcomes (death or cardiac hospitalization) over 32 months.
- Stepwise Cox regression model used to assess the association of AV-interval evaluation, pharmacotherapy, device function, and device type with outcomes.
Main Results:
- Failed AV-interval evaluation was independently associated with a higher risk of the primary endpoint (death or cardiac hospitalization) [HR = 1.72].
- Non-optimized pharmacotherapy dosages [HR = 2.12] and CRT/ICD combination devices [HR = 1.87] also increased endpoint risk.
- Satisfactory device function after the first implantation attempt was associated with a reduced risk [HR = 0.44].
Conclusions:
- Echocardiographic evaluation and optimization of the AV-interval in CRT patients are independently associated with improved clinical outcomes.
- These findings emphasize the importance of AV-interval assessment in daily clinical practice for heart failure patient care.
- Optimizing device settings through echocardiography can enhance the effectiveness of CRT in managing chronic heart failure.
Background:
Cardiac resynchronization therapy (CRT) is an established treatment option for symptomatic chronic heart failure (CHF) patients with pharmacological baseline therapy, but not all patients benefit from device therapy. One reason for this may be inadequate device settings. In real-world practice, echocardiographic evaluation of atrioventricular (AV) delay is not performed in a high proportion of patients, as the effect of electrical optimization of CRT is an issue open for investigation.
Materials And Methods:
We performed a retrospective observational study analysing the effect of AV-interval evaluation with echocardiography on long-term [32 (23?43) months] clinical outcome in 205 CHF patients. A stepwise Cox regression model including a co-morbidity score, failed AV-interval evaluation, satisfactory device function after the first implantation attempt, failure to reach 100% of the recommended renin-angiotensin system inhibitor and beta-blocker dose at follow-up and CRT device implantation compared with CRT in combination with an implanted cardioverter defibrillator (ICD) was applied.
Results:
In the total study cohort, 124 (60.5%) patients had reached the primary combined endpoint death or cardiac hospitalization and 59 (28.8%) had died. Cox regression analysis revealed that failed AV-interval evaluation [HR = 1.72 (1.19-2.49), P = 0.004] non-optimized CHF pharmacotherapy dosages [HR = 2.12 (1.32-3.42), P = 0.002], the presence of a CRT/ICD combination device [HR = 1.87 (1.28-2.71), P = 0.001] and satisfactory device function after the first implantation attempt [HR = 0.44 (0.25-0.77), P = 0.004] were associated with the primary endpoint.
Conclusion:
Echocardiographic evaluation of the AV-interval in patients with CRT was independently associated with improved clinical outcome, impacting on daily clinical practice of HF patient care.
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