Dual-Source Computed Tomography to Improve Prediction of Response to Cardiac Resynchronization Therapy

Massachusetts General Hospital38 enrolled

Overview

Cardiac Resynchronization Therapy (CRT) is a widely accepted treatment that has led to improved clinical outcomes for patients with refractory congestive heart failure (CHF), systolic dysfunction, and wide QRS duration. However, it requires implantation of an expensive device ($30,000) and about 1/3 of patients do not have clinical improvement. Inadequate amounts of LV dyssynchrony or suboptimal lead placement may limit clinical response. Dual-Source computed tomography (DSCT) allows for subtle detection during myocardial contraction for assessing LV dyssynchrony, and can also assess coronary venous anatomy and scar burden. Thus DSCT may be the ideal noninvasive modality to predict response to CRT.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Heart Failure - NYHA II - IV Wide QRS Complex

Interventions

Randomization of Pre-knowledge of CT coronary venographyOTHER

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Older than 18 years of age * Ability to provide informed consent * Planned CRT implantation * NYHA Functional Class II-IV heart failure * Echo Ejection Fraction less than or equal to 35% * QRS duration greater than or equal to 120 ms * Normal or mildly reduced kidney function (estimated serum creatinine less than or equal to 1.5 mg/dL or less than or equal to 1.3 mg/dL for diabetic subjects on metformin * For diabetic subjects on glucophage (metformin) they will be required to stop glucophage (metformin) for at least 48 hours after the administration of contrast. Exclusion Criteria: * Known allergy to iodine or iodinated contrast * Chronic persistent atrial fibrillation * Pregnancy or unknown pregnancy status * Subjects on glucophage (metformin) therapy that are unable or unwilling to discontinue therapy for 48 hours after CT scan * Known inadequate venous access for appropriate IV caliber placement * Iodinated contrast administration within the past 48 hours * Subjects who cannot hold their breath for 10-15 seconds

Outcomes

Primary Outcomes

Clinical Response to CRT

The clinical response to CRT will be adjudicated by two experienced cardiologists taking into account left ventricular ejection fraction, NYHA functional class, and patient global assessment score.

Time frame: 6 months post implantation of CRT

Secondary Outcomes

Major adverse cardiovascular events (MACE)

MACE defined as composite endpoints of death, cardiac transplant, left ventricular assist device, and HF hospitalization

Time frame: 2 years

Secondary endpoints

Change in NYHA Functional Class, Echo volumes and ejection fraction, Minnesota Quality of Life score, 6-minute walk distance, NT-proBNP levels, and hospitalization at 6 months

Time frame: 6 months