Advanced Cardiac Imaging in Cardiac Allograft Vasculopathy

NCT01927614 | Terminated

• 1 other identifier: CDHA_CAV
• Study Type: observational
• Target: 5
• Locations: 1 country
• Sites: 1

Brief Summary

Cardiac allograft vasculopathy (CAV) is a process of both immune and non-immune mediated thickening of the heart arteries of transplanted hearts. CAV limits the long term survival of heart transplant patients and is one of the common causes of death in the late post transplant period. Current methods of detecting CAV rest with invasive cardiac catheterization which carry repeated risks, as this test needs to be performed periodically through the life of a heart transplant patient. Traditional methods of coronary angiography identify CAV late in its course and is a crude method of evaluating coronary anatomy in heart transplant patients. Intravascular ultrasound is an additive tool that is able to detect early CAV before it becomes angiographically apparent, but still requires invasive cardiac catheterization to perform. However, it also limits assessment to the major epicardial arteries and does not give any information regarding the smaller branch vessels and cardiac microvasculature. Advances in cardiac CT and cardiac MRI hold potential to evaluate for CAV non-invasively. In addition, perfusion techniques may provide additional functional information regarding the status of the microvascular. In this pilot study, we aim to demonstrate the feasibility of cardiac CT and cardiac MRI with and without perfusion protocols, in patients post-heart transplant and to describe and compare CT and MRI findings in patients with established CAV versus those with no CAV, as diagnosed by standard invasive methods.

Conditions

Heart Transplantation

Keywords

Cardiac Allograft Vasculopathy; Cardiac MRI; Cardiac CT; Observational study

Outcome Measures

Primary Outcomes (1)

• Number of patients with adverse events from cardiac CT and cardiac MRI scan in heart transplant patients

  Testing the safety and feasibility of performing cardiac CT and MRI with perfusion protocols in heart transplant patients. Adverse events: serum creatinine increase \>25% from baseline within 1 week, drop in systolic blood pressure \>30mmHg, arrhythmias, chest pain, shortness of breath during drug infusion for perfusion protocols, inability to reduce heart rate \<80bpm for cardiac CT.

  Day 1

Secondary Outcomes (3)

• Describe CT and MRI imaging findings of established CAV

  Day 1

• Correlation between intimal thickening by IVUS imaging at cardiac catheterization and CCT and CMR perfusion abnormalities

  Day 1

• The association between CCT/CMR perfusion abnormalities one year post transplant and the development of angiographically apparent CAV, graft dysfunction, cardiac adverse events, and overall survival long term

  10 years

Study Arms (3)

Cohort 1

20 patients 1-year post heart transplant will undergo standard of care invasive cardiac catheterization but will also have intravascular ultrasound performed to measure the maximal intimal thickness of the proximal left anterior descending artery. Patients will be dichotomized into those with MIT \<0.5mm (10 patients) and those with MIT \>0.5mm (10 patients). All 20 patients will undergo both cardiac CT and cardiac MRI with perfusion imaging.

Radiation: Cardiac CT

Cohort 2

10 patients 1 year post heart transplant classified as CAV grade 0 by standard cardiac catheterization will undergo both cardiac CT and cardiac MRI with perfusion imaging.

Radiation: Cardiac CT

Cohort 3

10 patients with a diagnosis of CAV grade 1 as assessed by routine coronary angiogram at any time point post heart transplantation, will undergo cardiac CT and cardiac MRI with perfusion imaging

Radiation: Cardiac CT

Interventions

Cardiac CT RADIATION

A 128-slice dual-source CT system will be used (Somatom Definition Flash, Siemens Healthcare, Germany). The CT scan protocol will comprise 3 steps. 1. Prospectively gated calcium scoring. 2. Stress-myocardial CT perfusion. 3. Rest Coronary CT angiography and myocardial CT perfusion. Automated computed tomography dose index (CTDIvol) and dose- length-product (DLP) will be collected from the scanner, and effective dose will be calculated using the DLP conversion factor (0.014) for each component of the cardiac CT protocol. Based on local dose audits the predicted dose range will be 3.5 mSv to 8 mSv depending on patient body habitus.

Cohort 1; Cohort 2; Cohort 3

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Heart Transplant Patients

You may qualify if:

• \> 18 years of age
• Greater than or equal to 12 months post transplant
• Able to undergo cardiac CT and cardiac MRI

You may not qualify if:

• Creatinine clearance less than or equal to 45ml/min per 1.73m2)
• Severe aortic stenosis
• Long-QT syndrome (corrected QT \>440ms)
• AV block grade II/III
• Sick sinus syndrome
• New York Heart Association heart failure class III/IV
• Chronic obstructive pulmonary disease
• Asthma
• Atrial fibrillation
• Left ventricular ejection fraction \<50%
• Presence of a pacemaker or ICD
• Presence of any metal in body

Sponsors & Collaborators

• Nova Scotia Health Authority: lead

Study Sites (1)

Queen Elizabeth II Health Science Centre

Halifax, Nova Scotia, B3H 3A7, Canada

Location

Study Officials

• Brian Clarke, MD

  Staff Cardiologist and Clinical Assistant Professor, Division of Cardiology, QE II Health Science Centre, Dalhousie University and Capital District Health Authority

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 12, 2013
• First Posted: August 22, 2013
• Study Start: October 13, 2013
• Primary Completion: July 17, 2015
• Study Completion: July 17, 2015
• Last Updated: August 21, 2024

Record last verified: 2022-10

Locations

CA (1)