Cardiac resynchronization therapy (CRT) can have a positive impact on heart failure patients by improving cardiac function, quality of life and for some patients, life expectancy.1-3 Much like heart failure medication, CRT devices need regular optimization in response to clinical changes in the patient. Consider the following factors:
- Timing cycles change
- Major trials include optimization
- Few patients are being optimized today
- Risks of improper delay settings are many
Timing Cycles Change4, 5
Timing cycle optimization can be the first line of defense for non-responders and an opportunity to improve the outcomes of patients who do respond to CRT therapy.
Echo Optimization may not occur as frequently as needed due to:
- Lack of clear guidelines from ESC (European Society of Cardiology) and ACC/AHA (American College of Cardiology/American Heart Association)
- Typically being reserved only for CRT non-responders
- Skilled echo sonographer required
- Cost and time constraints
A study by O’Donnell, et al. demonstrates that timing cycles in CRT patients do change in optimal A-V and V-V delay over time in the total patient cohort.4
Clinical Perspectives
QuickOpt Timing Cycle Optimization is clinically proven to correlate with more time-consuming echo-based methods. QuickOpt optimization can be used for all St. Jude Medical CRT and dual-chamber ICD device recipients at implant or follow up. QuickOpt Timing Cycle Optimization provides a reliable and simple alternative to standard optimization techniques and has been clinically proven to correlate with echo-based optimization.
Acute IEGM AV Study - Max Echo VTI vs. IEGM VTI
A study by Baker, et al. compares IEGM methods and echocardiogram for cardiac resynchronization therapy in heart failure patients and dual-chamber ICD implants.6
QuickOpt Timing Cycle Optimization optimizes A-V and V-V intervals for responders and non-responders in about one minute, leading to a more efficient practice. QuickOpt Timing Cycle Optimization also can simplify patient management at a fraction of the time and cost of echo-based optimization methods.
Optimizing the A-V Delay can maximize ventricular filling and allow for proper timing of mitral valve closure. The V Sense, RV Pace, and LV Pace tests are used to calculate the optimal V-V Delay (Interventricular Pace Delay). The goal of optimizing the V-V Delay is to time the pacing stimuli so that the resultant LV and RV contractions meet near the ventricular septum. Regular optimization with QuickOpt Timing Cycle Optimization can improve patient outcomes by recommending optimal A-V and V-V delays.
Echocardiographic Measurements Before and After Optimization of CRT Systems
A clinical study in which Porciani, et al. assessed the effects of QuickOpt Timing Cycle Optimization on LV asynchrony and performance, as evaluated using real-time 3D echocardiography (RT3DE), supports QuickOpt Timing Cycle Optimization and CRT optimization.7 During follow up visits (9 +/- 8 months post implant), an echo test was performed before and after QuickOpt Timing Cycle Optimization of the A-V and V-V delays.
QuickOpt Timing Cycle Optimization suggested delays that resulted in a decrease in LV dyssynchrony and an improvement in LV systolic function.
1 Cazeau, S, et al. for the MUSTIC Study Investigators. “Effects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delay.” N Eng J Med 2001; 344:873-880.
2 Abraham, W, et al. “Cardiac resynchronization in heart failure.” (MIRACLE). N Engl J Med 346:1845-1853.
3 Bristow, M, et al. “Cardiac resynchronization therapy with or without and implantable defibrillator in advanced chronic heart failure.” N Engl J Med 2004;
350:2140–2150.
4 O’Donnell et al. Long-term variations in optimal programming of cardiac resynchronization therapy devices. PACE: Vol 28 Supp S24-S26 (Jan 2005).
5 Porciani MC. A real-time three-dimensional echocardiographic validation of intracardiac electrogram based method for optimizing cardiac resynchronization. PACE 2008; 31:56-63.
6 Baker et al. Acute evaluation of programmer-guided AV/PV and VV delay optimization comparing an IEGM method and echocardiogram for cardiac resynchronization therapy in heart failure patients and dual-chamber ICD implants. J Cardiovasc Electrophysiol 2007; 18:1-7.
7 Porciani et al. Temporal variation in optimal atrioventricular and interventricular delay during cardiac resynchronization therapy. J Cardiac Failure: Vol 12 No 9, 2006 p 715-719.