NCT01261065

Mechanisms of Improvement With Beta-Blocker Treatment in Heart Failure

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 55 (actual)
• Sponsor: Michael E. DeBakey VA Medical Center · Federal
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The overall hypothesis of this application is that the improvement in LV ejection performance following treatment with betablockers is due, at least in part, to improvement in intrinsic myocardial contractility.

Detailed description

The immediate specific objectives of this application are two-fold: (1) to determine whether the observed improvement in LV ejection performance is due to alterations in intrinsic cardiac myocardial contractility and (2) to determine whether changes in LV contractile reserve following an infusion of intravenous milrinone can be used to predict a salutary response to beta-blockers. The immediate specific objectives of this proposal will be addressed in the following two Specific Aims: In Specific Aim 1, we will determine whether the observed improvement in LV ejection fraction following treatment with beta-blockers is due to changes in intrinsic myocardial contractility, as opposed to changes in LV remodeling (i.e. reduction in LV volume) or changes in LV loading conditions. Changes in LV function will be evaluated using proven indexes, one an ejection phase index: the relation of end-systolic stress (ESS) to the mean velocity of fiber shortening (VCF), considered a relatively load independent measure of contractility. Changes in LV structure will be evaluated using echocardiography. In Specific Aim 2, we will determine whether the salutary response to beta-blockers can be predicted by measuring "contractile reserve", defined as a change in contractility determined by the relation of the mean velocity of fiber shortening (VCF) to end-systolic stress (ESS) in response to intravenous milrinone infusion at the cardiac catheterization lab prior to the institution of beta-blockade. The response to treatment with beta-blockers will be assessed by measurement of LV ejection fraction and LV end-diastolic volume by echocardiography after 6 months of treatment with beta-blockers, and these measurements will be correlated with the respective changes in contractile reserve measurement at baseline.

Conditions

• Heart Failure
• Cardiomyopathy

Interventions

Type	Name	Description
DRUG	carvedilol	Patients with heart failure and LVEF \< 35 % were treated with maximally tolerated dose of carvedilol for a period of six months. Target dose was 25 mg bid or 37.5 mg bid if patient's baseline weight \> 80 kg.

Timeline

• Start date: 2001-12-01
• Primary completion: 2005-10-01
• Completion: 2005-10-01
• First posted: 2010-12-16
• Last updated: 2025-09-26

Locations

1 site across 1 country: United States