Left Ventricular Structural Predictors of Sudden Cardiac Death

This study is currently recruiting participants. (see Contacts and Locations)
Verified February 2013 by Johns Hopkins University
Sponsor:
Collaborators:
Donald W. Reynolds Foundation
Christiana Care Health Services
Information provided by (Responsible Party):
Katherine C. Wu, Johns Hopkins University
ClinicalTrials.gov Identifier:
NCT01076660
First received: February 25, 2010
Last updated: February 19, 2013
Last verified: February 2013
  Purpose

Sudden cardiac death (SCD) poses a significant health care challenge with high annual incidence and low survival rates. Implantable cardioverter defibrillators (ICDs) prevent SCD in patients with poor heart function. However, the critical survival benefit afforded by the devices is accompanied by short and long-term complications and a high economic burden. Moreover, in using current practice guidelines of reduced heart function, specifically left ventricular ejection fraction (LVEF)≤35%, as the main determining factor for patient selection, only a minority of patients actually benefit from ICD therapy (<25% in 5 years). There is an essential need for more robust diagnostic approaches to SCD risk stratification.

This project examines the hypothesis that structural abnormalities of the heart itself, above and beyond global LV dysfunction, are important predictors of SCD risk since they indicate the presence of the abnormal tissue substrate required for the abnormal electrical circuits and heart rhythms that actually lead to SCD. Information about the heart's structure will be obtained from cardiac magnetic resonance imaging and used in combination with a number of other clinical risk factors to see if certain characteristics can better predict patients at risk for SCD.


Condition
Ischemic Cardiomyopathy
Nonischemic Cardiomyopathy

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Left Ventricular Structural Predictors of Sudden Cardiac Death [Substudy of: Functional Energetics and Imaging for Phenotypic Characterization of Patients at Risk for Sudden Cardiac Death, See Also NCT000181233]

Resource links provided by NLM:


Further study details as provided by Johns Hopkins University:

Primary Outcome Measures:
  • Composite SCD outcomes [ Time Frame: Every 6 months for 5 years ] [ Designated as safety issue: No ]
    The first occurrence of an adjudicated appropriate ICD firing for ventricular tachycardia/ventricular fibrillation or cardiac death not treated by the ICD.


Secondary Outcome Measures:
  • Composite cardiac outcomes [ Time Frame: Every 6 months for 5 years ] [ Designated as safety issue: No ]
    The first occurrence of an adjudicated appropriate ICD firing for ventricular tachycardia/ventricular fibrillation, hospitalization for heart failure or cardiac death.


Estimated Enrollment: 400
Study Start Date: October 2003
Estimated Study Completion Date: June 2015
Estimated Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Detailed Description:

Sudden cardiac death (SCD) poses a significant health care challenge with high annual incidence and low survival rates. Implantable cardioverter defibrillators (ICDs) prevent SCD in patients with left ventricular (LV) systolic dysfunction. However, the critical survival benefit afforded by the devices is accompanied by short and long-term complications and a high economic burden. Moreover, in using current practice guidelines of LV ejection fraction (LVEF)≤35% as the main determining factor for patient selection, only a minority of patients actually benefit from ICD therapy (<25% in 5 years). There is an essential need for more robust diagnostic approaches to SCD risk stratification.

This project examines the hypothesis that LV structural abnormalities above and beyond global LV dysfunction are important predictors of SCD risk since they indicate the presence of abnormal pathophysiologic substrate required for the ventricular arrhythmogenicity leading to SCD. This premise is supported by pre-clinical models and limited patient cohort studies examining the contribution of individual LV structural indices. However, there has been no prospective study of primary prevention ICD candidates in sufficiently large numbers to investigate the incremental value of a comprehensive assessment of LV structure on SCD risk over and above that of LVEF and readily available demographic and clinical variables.

LV structure can be quantified in detail using cardiac magnetic resonance imaging with late gadolinium enhancement (CMR-LGE). Specifically, accurate assessment of global LV function, volumes, mass, geometry, and infarct/scar characteristics are feasible and obtainable clinically in a single examination. We aim to examine whether or not any of these CMR indices or combination of indices are better able to discriminate between patients with high versus low susceptibility to SCD within the broader population of reduced LVEF patients. If the results of these studies demonstrate that LV structure is an important prognostic risk factor, it may be then be possible to more specifically focus ICD therapy to those who are most likely to benefit and avoid unnecessary device implantations.

  Eligibility

Ages Eligible for Study:   21 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Patients with LV ejection fraction (LVEF) ≤35% of ischemic or nonischemic etiology (as measured by a clinical echocardiogram, ventriculogram, or radionuclide study) referred clinically for ICD insertion for primary prevention purposes (i.e. no prior history of sustained ventricular arrhythmias)

Criteria

Inclusion Criteria:

  • LVEF≤35%, referred clinically for ICD insertion for primary prevention purposes (i.e. no prior history of sustained ventricular arrhythmias)
  • Between the ages of 21 and 80 years old
  • Permission of the patient's clinical attending physician

Exclusion Criteria:

  • Patients who refuse or are unable to give consent.
  • Individuals with contraindications to MRI (i.e. implanted metallic objects such as pre-existing cardiac pacemakers, cerebral clips or indwelling metallic projectiles)
  • Minors.
  • Pregnant women.
  • NYHA Class IV heart failure.
  • Chronic renal insufficiency with creatinine clearance<60 ml/min; acute renal insufficiency of any severity
  • Claustrophobia
  • Prior adverse reaction to gadolinium-based contrast
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01076660

Contacts
Contact: Jeannette Walker, RN 410-502-7310 jhoefli1@jhmi.edu

Locations
United States, Delaware
Christiana Care Health Services Not yet recruiting
Newark, Delaware, United States, 19718
United States, Maryland
Johns Hopkins Medical Institutions Recruiting
Baltimore, Maryland, United States, 21287
Principal Investigator: Katherine Wu, MD         
Sponsors and Collaborators
Johns Hopkins University
Donald W. Reynolds Foundation
Christiana Care Health Services
Investigators
Principal Investigator: Katherine Wu, MD Johns Hopkins University
Study Director: Robert G Weiss, MD Johns Hopkins University
  More Information

Publications:

Responsible Party: Katherine C. Wu, Associate Professor of Medicine, Johns Hopkins University
ClinicalTrials.gov Identifier: NCT01076660     History of Changes
Other Study ID Numbers: Reynolds03073103
Study First Received: February 25, 2010
Last Updated: February 19, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Johns Hopkins University:
Ischemic cardiomyopathy
Nonischemic cardiomyopathy
Implantable cardioverter defibrillator
Sudden Cardiac Death
Ventricular tachycardia
Ventricular fibrillation

Additional relevant MeSH terms:
Death
Ischemia
Death, Sudden, Cardiac
Cardiomyopathies
Pathologic Processes
Heart Arrest
Heart Diseases
Cardiovascular Diseases
Death, Sudden

ClinicalTrials.gov processed this record on July 22, 2014