Prediction of ARrhythmic Events With Positron Emission Tomography

Ischemic Cardiomyopathy Clinical Trial

— PAREPET  

Official title:

Hibernating Myocardium and Sudden Cardiac Death

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01400334
• Other study ID #: HL76252
• Status: Completed
• Start date: July 2004
• Est. completion date: December 2012

Study information

• Verified date: October 2020
• Source: State University of New York at Buffalo
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The hypothesis of PAREPET is that hibernating myocardium (viable myocardium with reduced resting flow) and/or viable but denervated myocardium can predict the risk of sudden death in subjects with ischemic cardiomyopathy.

Description:

Currently available electrophysiological approaches are limited in their ability to identify the majority of patients with CAD and LV dysfunction that succumb to sudden cardiac death (SCD). Half of the patients developing SCD are not inducible at electrophysiological testing underscoring the need for new ways to identify substrates leading to arrhythmic death. Viable chronically dysfunctional with reduced resting flow, or hibernating myocardium, not amenable to revascularization appears to be a major risk factor for subsequent cardiac death and is present in up to 60% of patients with ischemic cardiomyopathy. Cause specific mortality data is limited but appears to be arrhythmic rather than from fatal myocardial infarction or progressive heart failure. Revascularization improves survival but most patients with hibernating myocardium are managed medically due to prohibitive procedural risks or technical limitations. Basic studies in swine with hibernating myocardium demonstrate SCD arising from VT/VF in the absence of myocardial scar or heart failure. The central hypothesis of this proposal is that the presence of hibernating myocardium as opposed to scar identifies a large subset of patients with ischemic cardiomyopathy that are at high risk for SCD. We further hypothesize that this risk is related to inhomogeneity in sympathetic innervation arising from chronic repetitive ischemia. PAREPET is a prospective observational study that will enroll patients with coronary disease, Class I-III heart failure and an ejection fraction ≤35%. Using positron emission tomography (PET), the frequency and amount of hibernating myocardium will be quantified in patients that are not candidates for coronary revascularization. Three Specific Aims are proposed. Aim 1 will determine whether imaging the mismatch between viability (preserved 18F-2-deoxyglucose) and reduced resting flow (13NH3) can predict an increased risk of SCD (or ICD discharge for VT/VF as a surrogate end-point) in hibernating myocardium. Aim 2 will image norepinephrine uptake using 11C-hydroxyephedrine to determine whether inhomogeneity in myocardial sympathetic innervation predicts SCD risk better than viability testing. Aim 3 will identify whether the substrate identified by PET is stable after an aborted SCD event by evaluating temporal changes in function, viability and sympathetic innervation in patients with an ICD. Our long-term objective is to develop better approaches to identify patients with CAD who are most likely to benefit from primary prevention of SCD with placement an ICD.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 257
• Est. completion date: December 2012
• Est. primary completion date: December 2012
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• LV EF =35% (by nuclear imaging, cardiac catheterization or echocardiography)

• Coronary artery disease documented by cardiac catheterization, a history of definite myocardial infarction, or reversible ischemia on nuclear imaging

• New York State Heart Association functional Class I-III heart failure

• Not a candidate for surgical or percutaneous coronary revascularization at the time of enrollment

Exclusion Criteria:

• History of resuscitated sudden cardiac death, sustained ventricular tachycardia, appropriate implantable cardiac defibrillator (ICD) discharge, or unexplained syncope

• Myocardial infarction within 30 days

• Coronary artery bypass grafting within 1 year

• Percutaneous intervention within 3 months

• Claustrophobia or physical limitation that would preclude PET scanning

• Pregnancy

• Tricyclic antidepressant drug therapy

• Comorbidities that would be expected to result in noncardiac death within 2 years

• Inability to provide informed consent

Related Conditions & MeSH terms

• Cardiomyopathies
• Hibernating Myocardium
• Ischemic Cardiomyopathy
• Nerve; Disorder, Sympathetic

Intervention

Radiation:
• Positron Emission Tomography
Quantification of cardiac function using positron emission tomography and: a)11C-meta-hydroxyephedrine [HED, 20 mCi (740 MBq)] to quantify sympathetic nerve function, b) 13N-ammonia [NH3, 20 mCi (740 MBq)] for regional perfusion, and c) 18F-2-deoxyglucose [FDG; 6.5 mCi (241 MBq)] administered during a hyperinsulinemic-euglycemic clamp to assess viability.

Locations

Country	Name	City	State
United States	SUNYBuffalo	Buffalo	New York

Sponsors (1)

Lead Sponsor	Collaborator
State University of New York at Buffalo

Country where clinical trial is conducted

United States, 

References & Publications (4)

Al-Zaiti SS, Fallavollita JA, Canty JM Jr, Carey MG. Electrocardiographic predictors of sudden and non-sudden cardiac death in patients with ischemic cardiomyopathy. Heart Lung. 2014 Nov-Dec;43(6):527-33. doi: 10.1016/j.hrtlng.2014.05.008. Epub 2014 Jul 2 — View Citation

Al-Zaiti SS, Fallavollita JA, Wu YW, Tomita MR, Carey MG. Electrocardiogram-based predictors of clinical outcomes: a meta-analysis of the prognostic value of ventricular repolarization. Heart Lung. 2014 Nov-Dec;43(6):516-26. doi: 10.1016/j.hrtlng.2014.05. — View Citation

Fallavollita JA, Heavey BM, Luisi AJ Jr, Michalek SM, Baldwa S, Mashtare TL Jr, Hutson AD, Dekemp RA, Haka MS, Sajjad M, Cimato TR, Curtis AB, Cain ME, Canty JM Jr. Regional myocardial sympathetic denervation predicts the risk of sudden cardiac arrest in — View Citation

Fallavollita JA, Luisi AJ Jr, Michalek SM, Valverde AM, deKemp RA, Haka MS, Hutson AD, Canty JM Jr. Prediction of arrhythmic events with positron emission tomography: PAREPET study design and methods. Contemp Clin Trials. 2006 Aug;27(4):374-88. Epub 2006 May 2. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Sudden Cardiac Death	Adjudicated sudden cardiac death and implantable cardiac defibrillator therapy for fast ventricular tachycardia (>240 bpm) or ventricular fibrillation.	every 3 months
Secondary	Cardiac Death	Sudden cardiac death and adjudicated non-sudden cardiac death	every 3 months