Validating an Idiopathic Dilated Cardiomyopathy Diagnosis Using Cardiovascular Magnetic Resonance: The Dilated
Garrie J Haas1,2,3, Karolina M Zareba2,3, Hanyu Ni3,4
1Advanced Heart Failure and Cardiac Transplant Program (G.J.H., R.E.H.), all in the Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus.
Insights
Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) can identify myocardial scar in dilated cardiomyopathy (DCM) patients. A small percentage of patients with idiopathic DCM showed ischemic patterns on LGE-CMR, suggesting potential underlying coronary artery disease.
Area of Science:
- Cardiology
- Medical Imaging
- Precision Medicine
Background:
- Coronary angiography is a standard diagnostic tool for coronary artery disease (CAD) and differentiating causes of dilated cardiomyopathy (DCM).
- Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) is an emerging technique for detecting myocardial scar and determining cardiomyopathy etiology.
- Distinguishing between idiopathic DCM and ischemic cardiomyopathy is crucial for appropriate patient management.
Purpose of the Study:
- To evaluate the utility of LGE-CMR in identifying myocardial scar in patients diagnosed with idiopathic DCM.
- To assess the prevalence of ischemic-pattern LGE in a cohort of patients with idiopathic DCM.
- To investigate potential discrepancies between clinical adjudication of idiopathic DCM and findings on LGE-CMR.
Main Methods:
- A post hoc analysis of available CMR reports was conducted on patients enrolled in the DCM Precision Medicine Study.
- Patients with left ventricular dilation and dysfunction, clinically adjudicated as idiopathic DCM, were included.
- Patterns of LGE on CMR were classified as no LGE, ischemic-pattern LGE (subendocardial/transmural), or nonischemic LGE (midmyocardial/epicardial).
Main Results:
- Of 327 patients with LGE-CMR data, 178 (54.4%) showed LGE.
- 156 of those with LGE had patterns consistent with idiopathic DCM.
- 22 patients (6.7%) exhibited an ischemic-pattern of LGE, despite initial clinical adjudication of idiopathic DCM.
Conclusions:
- An ischemic pattern of LGE was identified in a small subset of patients with clinically diagnosed idiopathic DCM.
- These findings highlight the potential for LGE-CMR to identify underlying ischemic processes missed by initial clinical review or standard angiography.
- Further investigation may be warranted for idiopathic DCM patients with ischemic-pattern LGE to confirm or rule out significant coronary artery disease.
Background:
Coronary angiography to identify coronary artery disease has been foundational to distinguish the cause of dilated cardiomyopathy (DCM), including the assignment of idiopathic or ischemic cardiomyopathy. Late gadolinium enhancement (LGE) with cardiovascular magnetic resonance (CMR) has emerged as an approach to identify myocardial scar and identify etiology.
Methods:
The DCM Precision Medicine Study included patients with left ventricular dilation and dysfunction attributed to idiopathic DCM, after expert clinical review excluded ischemic or other cardiomyopathies. Ischemic cardiomyopathy was defined as coronary artery disease with >50% narrowing at angiography of ≥1 epicardial coronary artery. CMR was not required for study inclusion, but in a post hoc analysis of available CMR reports, patterns of LGE were classified as (1) no LGE, (2) ischemic-pattern LGE: subendocardial/transmural, (3) nonischemic LGE: midmyocardial/epicardial.
Results:
Of 1204 idiopathic DCM patients evaluated, 396 (32.9%) had a prior CMR study; of these, 327 (82.6% of 396) had LGE imaging (mean age 46 years; 53.2% male; 55.4% White); 178 of the 327 (54.4%) exhibited LGE, and 156 of the 178 had LGE consistent with idiopathic DCM. The remaining 22 had transmural or subendocardial LGE. Of these 22, coronary angiography was normal (13), showed luminal irregularities (3), a distant thrombus (1), coronary artery disease with <50% coronary artery narrowing (1), or was not available (4).
Conclusions:
Of 327 probands enrolled in the DCM Precision Medicine Study cohort who had LGE-CMR data available, an ischemic-pattern of LGE was identified in 22 (6.7%), all of whom had idiopathic DCM as adjudicated by expert clinical review.
Registration:
URL: https://www.
Clinicaltrials:
gov; Unique identifier: NCT03037632.
More Related Videos
Related Concept Videos
01:30Cardiomyopathy II: Dilated Cardiomyopathy
01:21Imaging Studies for Cardiovascular System IV: CMRI
01:29Cardiomyopathy III: Hypertrophic Cardiomyopathy
01:29Cardiomyopathy IV: Restrictive Cardiomyopathy
01:29Cardiomyopathy V: Interprofessional Care
01:25Cardiomyopathy I: Introduction and Classification