Adaptive Cardiac Resynchronization Therapy Study (aCRT)
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|ClinicalTrials.gov Identifier: NCT00980057|
Recruitment Status : Completed
First Posted : September 18, 2009
Results First Posted : October 16, 2018
Last Update Posted : October 16, 2018
|Condition or disease||Intervention/treatment||Phase|
|Heart Failure||Device: Adaptive CRT (aCRT) Device: Echo||Not Applicable|
The trial has 3 primary end points:
- to demonstrate that over 6-month follow-up, the proportion of the patients improved in the aCRT arm is at least as high as in the Echo arm
- to demonstrate that cardiac function is similar when using aCRT versus echo-optimized settings
- to demonstrate that aCRT does not result in inappropriate AV or VV delay settings
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||522 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Double (Participant, Investigator)|
|Official Title:||Adaptive Cardiac Resynchronization Therapy Study|
|Actual Study Start Date :||October 1, 2009|
|Actual Primary Completion Date :||August 4, 2011|
|Actual Study Completion Date :||March 8, 2012|
Experimental: Adaptive CRT (aCRT) arm
Intervention: Cardiac resynchronization therapy (CRT-D) with Adaptive CRT algorithm ON
Device: Adaptive CRT (aCRT)
Adaptive CRT (aCRT) is an algorithm, which provides ambulatory adjustment of pacing configuration (LV-only or BiV) and AV and VV delays based on periodic automatic evaluation of electrical conduction to optimize cardiac function
Other Name: aCRT
Active Comparator: Echo-optimized arm
Intervention: Cardiac resynchronization therapy (CRT-D) with standard biventricular pacing (Adaptive CRT algorithm OFF)
Standard BiV pacing with settings optimized using a standardized echocardiographic protocol
Other Name: Control
- Percentage of Patients With Improved Heart Failure Outcomes Clinical Composite Score [ Time Frame: randomization to six month visit ]
Patients considered worsened if they died, were hospitalized with worsening heart failure (HF), crossed over to other arm, demonstrated worsening in New York Heart Association (NYHA) functional class, or reported moderately/markedly worse on 'patient global assessment' compared to before CRT implant. Patients are improved if they are not worsened and have an improved NYHA or reported moderately/markedly improved on the 'patient global assessment' compared to before CRT implant
Global assessment question for the patient: Specifically in reference to your heart failure symptoms, how do you feel today as compared to how you felt before your CRT system was implanted? O Markedly improved O Moderately improved O Mildly improved O No change O Slightly worse O Moderately worse O Markedly worse
- Correlation Between Aortic Velocity Time Integral (AoVTI) at Adaptive CRT and Echo-optimized Device Settings [ Time Frame: randomization visit and six month visit ]Correlation between aortic velocity time integral (AoVTI) at Adaptive CRT and echo-optimized device settings. AoVTI is an echocardiographic representative of stroke volume and cardiac performance.
- Percentage of Patients With a Safety Event (Inappropriate AV or VV Delay Settings Related to the aCRT Feature) [ Time Frame: randomization to 6 months post randomization ]For each subject, the Adaptive CRT-determined AV and VV delay settings from randomization up to 183-days post-randomization were evaluated to identify any period of 28-days with a wide delay range (>60 ms)
- Right Ventricular Pacing Percentage [ Time Frame: implant to six months post randomization ]The percentage of time the right ventricle is paced by the device
- Change in Left Ventricular End Systolic Volume Index (LVESVi) [ Time Frame: baseline to six month visit ]Change in left ventricular end systolic volume index (LVESVi).
- Change in Left Ventricular Ejection Fraction (LVEF) [ Time Frame: baseline to six month visit ]
- Change in New York Heart Association (NYHA) Classification [ Time Frame: baseline to six month visit ]
The New York Heart Association (NYHA) Functional Classification places patients in one of four categories based on how much they are limited during physical activity.
Class - Patient Symptoms I - No limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea (shortness of breath).
II- Slight limitation of physical activity. Comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea (shortness of breath).
III- Marked limitation of physical activity. Comfortable at rest. Less than ordinary activity causes fatigue, palpitation, or dyspnea.
IV- Unable to carry on any physical activity without discomfort. Symptoms of heart failure at rest. If any physical activity is undertaken, discomfort increases.
- Change in Distance Walked During the Six Minute Hall Walk [ Time Frame: baseline to six month visit ]
- Change in Quality of Life Measured by the Minnesota Living With Heart Failure Questionnaire (MLWHF) [ Time Frame: baseline to six month visit ]The MLWHF is a 21 question survey. Scores range from 0-105, with lower scores indicating better health.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00980057
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|Study Chair:||Adaptive CRT Trial Leader||Medtronic|