Clinical trial NCT01466621: Response to Cardiac Resynchronization Therapy of Previously Right Ventricular Paced Heart Failure Patients
Official title: Response to Cardiac Resynchronization Therapy of Previously Right Ventricular Paced Heart Failure Patients
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Heart Failure
Pacing Induced Dyssynchrony
Keywords: cardiac resynchronization therapy
heart failure
mortality
Lead sponsor: Allina Health System
Sponsor class: OTHER
Collaborators: name: Boston Scientific Corporation
First posted: 2011-11-08
Enrollment: 743
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: A retrospective review of patients receiving CRT at United Heart \& Vascular Clinic between 2003 and 2009.

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.

Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

Primary outcomes:
measure: Death from any cause
timeFrame: Average of 4 years
measure: Cardiovascular Hospitalization
timeFrame: Average of 4 years
Secondary outcomes:
measure: Change in ejection fraction
timeFrame: Approximately one year
Other outcomes:
Locations:
city: St. Paul
country: United States
facility: United Heart & Vascular Clinic
state: Minnesota
Study officials:
affiliation: United Heart & Vascular Clinic
name: Alan J Bank, MD
role: PRINCIPAL_INVESTIGATOR
References: