Clinical Trials Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Sep 26, 2018; 10(9): 110-118
Published online Sep 26, 2018. doi: 10.4330/wjc.v10.i9.110
Accuracy of myocardial viability imaging by cardiac MRI and PET depending on left ventricular function
Peter Hunold, Heinz Jakob, Raimund Erbel, Jörg Barkhausen, Christina Heilmaier
Peter Hunold, Jörg Barkhausen, Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck 23538, Germany
Heinz Jakob, Department of Thoracic and Cardiovascular Surgery, West German Heart Center, University of Duisburg-Essen, University Hospital Essen, Essen 45122, Germany
Raimund Erbel, Department of Cardiology, West German Heart Center, University of Duisburg-Essen, University Hospital Essen, Essen 45122, Germany
Christina Heilmaier, Department of Radiology and Nuclear Medicine, Stadtspital Triemli, Zürich 8063, Switzerland
Author contributions: Hunold P and Heilmaier C designed research; Hunold P, Heilmaier C, Barkhausen J, Erbel R and Jakob H acquired data; Hunold P, Heilmaier C and Barkhausen J analyzed data; Heilmaier C and Hunold P wrote the paper; Barkhausen J, Erbel R and Jakob H revised and approved final manuscript version
Institutional review board statement: This study was reviewed and approved by the Institutional review board of the Medical Faculty of the University Essen, Germany (No. 00-142-1497).
Clinical trial registration statement: N/A.
Informed consent statement: All patients gave written informed consent to participate in the study prior to study inclusion and agreed to the evaluation and publication of their anonymized data.
Conflict-of-interest statement: None of the authors states a conflict of interest concerning firms and products reported in this study.
Open-Access: This article is an open-access article which selected by an in-house editor and fully peer-reviewed by external reviewers. It distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Peter Hunold, MD, Assistant Professor, Vice Chairman, Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, Lübeck 23538, Germany. peterhunold@icloud.com
Telephone: +49-451-50017010 Fax: +49-451-50017004
Received: March 29, 2018
Peer-review started: March 29, 2018
First decision: April 23, 2018
Revised: June 28, 2018
Accepted: August 5, 2018
Article in press: August 5, 2018
Published online: September 26, 2018
ARTICLE HIGHLIGHTS
Research background

Cardiac magnetic resonance imaging (CMR) and positron emission tomography (PET) have been established for myocardial viability imaging in coronary artery disease (CAD). However, differences in accuracy have been reported. It has been shown that CMR provides higher sensitivity in detecting small scars due to the significantly higher spatial resolution. So far, no data are available on differences in diagnostic accuracy depending on left ventricular (LV) function although it might be suggested that LV volumes and wall thickness, for example, might have an impact on the sensitivity.

Research motivation

The above mentioned missing data have been collected in our large study and have now been made available. This study might help to better understand the advantages and disadvantages of the two different methods.

Research objectives

The primary objective of this research was to compare contrast-enhanced CMR and fluorodeoxyglucose-PET for the evaluation of myocardial viability in known CAD under different LV function conditions.

Research methods

One-hundred-five CAD patients were examined by CMR and PET. Myocardial scars were rated in both CMR and PET on a segmental basis in each 8 mm thick short axis slice concerning presence and extent of myocardial scar after myocardial infarction. For each of the evaluated 5518 segments, direct comparison was performed and three patient groups with different LV function were analyzed. In particular two aspects, diagnostic accuracy has been evaluated: (1) scar detection; and (2) functional improvement estimation by the two methods.

Research results

As expected, CMR has a higher sensitivity for scar detection and, therefore, is less optimistic than PET in the prediction of functional recovery after revascularization. In the different LV function groups, CMR found more scar segments than PET in subjects with EF < 30% and EF 30%-50% (44% vs 40 %; P < 0.005), whereas CMR revealed less scars than PET in patients with EF > 50%.

Research conclusions

There are differences in the diagnostic accuracy between both modalities that have not been described, yet. This new knowledge helps to understand the strengths and weaknesses of the two modalities. One should keep in mind that particularly in severely impaired LV function - where viability really matters - CMR is able to detect more scars. In those cases, using CMR instead of PET could prevent unnecessary revascularizations and accompanying complications.

Research perspectives

This study could initiate more research on particular myocardial viability imaging aspects to better sort outpatient conditions that influence the accuracy of available techniques.