Tissue Doppler Imaging (TDI) Versus Electrocardiography (ECG) Interventricular Pacing Delay Optimization in Cardiac Resynchronization Therapy (CRT)
The aim of this study was to compare the response to cardiac resynchronization therapy when the interventricular pacing interval was optimized by Tissue Doppler Imaging (TDI) to response when it was optimized following QRS width criteria.
Cardiac Resynchronization Therapy
Device: Interventricular pacing delay optimization by using Tissue Doppler-derived displacement curves
Device: Electrocardiographic optimization of the interventricular pacing delay according to QRS width
|Study Design:||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
- 6-month echocardiographic response [ Designated as safety issue: No ]Reduction of the end-systolic volume (measured in mililiters according to transthoracic echocardiography) of >10% as compared to the baseline value.
- 6-month clinical response [ Designated as safety issue: No ]Combined end-point consisting in no death due to cardiovascular reasons, no heart transplantation and distance increase of >10% (measured in meters) in the 6-minute walking test.
Active Comparator: Tissue Doppler Imaging (TDI) optimization
Interventricular pacing delay optimized according to Tissue-Doppler echocardiography
|Device: Interventricular pacing delay optimization by using Tissue Doppler-derived displacement curves|
Active Comparator: Electrocardiographic optimization
Interventricular pacing delay optimized according to QRS width observation in the 12-lead surface electrocardiogram
|Device: Electrocardiographic optimization of the interventricular pacing delay according to QRS width|