Response to Cardiac Resynchronization Therapy of Previously Right Ventricular Paced Heart Failure Patients

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT01466621

Enrollment

743

Registered

2011-11-08

Start date

2011-10-31

Completion date

2014-06-30

Last updated

2016-02-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Heart Failure, Pacing Induced Dyssynchrony

Keywords

cardiac resynchronization therapy, heart failure, mortality

Brief summary

The present proposal is designed to investigate the response to CRT in patients who were previously paced from the right ventricle (RV). The negative physiologic and structural changes associated with chronic RV pacing are well documented, but patient response following upgrade to CRT after chronic RV pacing has not been well characterized in a large cohort.

Detailed description

The RV apex has historically been used as the site for ventricular pacing in cases of sinus node dysfunction or atrioventricular block because of its relatively accessible location for lead implantation. Initial studies showed RV pacing improved symptoms, exercise capacity, quality of life, and survival in these patients.11-13 However, more recent studies have illustrated that chronic RV pacing may actually impair LV systolic function and increase the risks of heart failure, hospitalization, and death in some patients. The primary hypothesis is that patients upgraded to CRT from a RV pacemaker respond better than those receiving CRT as a first time device. To test this hypothesis the investigators will compare changes in cardiac size and function, and hospitalization and survival rates between the two patient groups. The second hypothesis will investigate whether changes in septal dyssynchrony are correlated with changes in ejection fraction in previously RV paced patients. The investigators believe that the patients with the most improvement in septal dyssynchrony due to RV pacing will see the greatest improvement in LV function following upgrade to CRT. A significant correlation between change in IM-S and change in EF will support the hypothesis.

Interventions

None listed

Study design

Time perspective

RETROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Received a CRT device between 2003 and 2009 at United Heart & Vascular Clinic * QRS duration \> 120 msec * Pre-CRT ejection fraction =\< 35%

Design outcomes

Primary

Measure	Time frame	Description
Death from any cause	Average of 4 years	Retrospectively measure the time in days from device implant to death, if applicable.
Cardiovascular Hospitalization	Average of 4 years	Retrospectively measure the time in days from device implant to hospitalization, if applicable.

Secondary

Measure	Time frame	Description
Change in ejection fraction	Approximately one year	A measure of cardiac performance.

Countries

United States

Outcome results