NCT00132977
RethinQ Study - Evaluating Pacing in Heart Failure Patients
PHASE3
COMPLETED
NCT00132977
INTERVENTIONAL
Resynchronization Therapy in Normal QRS (RethinQ) Clinical Investigation
Patients with heart failure have a pumping action of the ventricles in which one ventricle contracts before the other ventricle. This uncoordinated (unsynchronized) pumping is due to a delay in the stimulation of the left ventricle because of its increased size. Pacing both the right and the left side of the heart (or cardiac resynchronization therapy \[CRT\]) has been proven to be effective in the treatment of heart failure (HF). Current market-approved devices combine both pacing (CRT) and shocking (implantable cardioverter defibrillator \[ICD\]) therapy for patients who have severe heart failure and are at risk for developing life-threatening heart rhythms. These devices provide an electrical pacing stimulus to both ventricles and may help the heart contract in a more coordinated way and improve heart failure symptoms.
The investigational portion of this trial involves the implantation of a market-approved CRT implantable cardioverter defibrillator (CRT-D) system in patients who do not meet the current criteria for a CRT implant. In order to receive a CRT-D implant today, patients must have heart failure symptoms, have a weakened heart muscle, and have uncoordinated pumping of the heart. To demonstrate this uncoordinated pumping of the heart, a test (electrocardiogram \[ECG\]) is done. It is believed that by using a different test (echocardiogram) to measure whether this uncoordinated pumping is present, more patients will be identified that will benefit from CRT-D therapy. This study will look at whether patients identified by using this echocardiogram test show a benefit from having this CRT-D therapy.
Inclusion Criteria:
* Have an approved indication for implantation of an ICD.
* Have advanced HF with a New York Heart Association (NYHA) Classification of III, despite receiving optimal pharmacological therapy.
* Have a stable heart failure medical regimen.
* Have a left ventricular ejection fraction (LVEF) <= 35%.
* Have evidence of mechanical dyssynchrony as measured by echocardiography using tissue Doppler imaging or M-mode.
* Have a QRS duration < 130 ms (present in all ECG leads).
* Have the ability to complete exercise stress testing and 6-minute hall walk test, with the only limiting factors being related to cardiac fitness.
* Have the ability to independently comprehend and complete a quality of life questionnaire.
* Have the ability to provide informed consent for study participation and be willing and able to comply with the prescribed follow-up tests and schedule of evaluations.
Exclusion Criteria:
* Have a standard bradycardic indication for pacing.
* Have been previously treated with CRT.
* Have continuous atrial fibrillation \[AF\] (continuous is defined as AF lasting > 1 month) within 1 year prior to enrollment or have undergone cardioversion for AF in the past month.
* Have the ability to walk > 450 meters during the 6-minute walk test.
* Have a NYHA Classification of I, II or IV.
* Have symptomatic chronic obstructive pulmonary disease (COPD) as it relates to exercise ability.
* Have a classification of Status 1 for cardiac transplantation or consideration for transplantation over the next 6 months.
* Have had a recent myocardial infarction, unstable angina or cardiac revascularization (percutaneous transluminal coronary angioplasty \[PTCA\] or coronary artery bypass graft \[CABG\]) within 40 days of enrollment.
* Have had a recent cerebrovascular accident (CVA) or transient ischemic attack (TIA) within 3 months of enrollment.
* Have severe musculoskeletal disorder(s).
* Pregnant or planning for pregnancy in the next 6 months.
* Currently participating in, or have participated in any clinical investigation within the last 30 days (the only exception being that of a registry trial).
* Have a life expectancy of less than 6 months.
* Less than 18 years of age.
Heart Failure
- TREATMENT
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- Type: DEVICE
- Name: Cardiac Resynchronization Therapy
- Description:
- Arm Group Labels:
- Abbott Medical Devices