- Oral presentation
- Open Access
Delayed-enhanced magnetic resonance imaging for identifying the ventricular arrhythmia substrate in non-ischemic cardiomyopathy
© Desjardins et al; licensee BioMed Central Ltd. 2009
- Published: 28 January 2009
- Ventricular Tachycardia
- Ventricular Arrhythmia
- Scar Tissue
- Premature Ventricular Complex
Scar tissue is often noted in the myocardium of patients with non-ischemic cardiomyopathy. Delayed-enhanced magnetic resonance imaging (DE-MRI) can precisely define the extension and distribution of this scar tissue. Such scar tissue can act as arrhythmogenic substrate and lead to ventricular arrhythmia. Patients with non-ischemic cardiomyopathy who present with ventricular arrhythmia can undergo ablation therapy to eliminate these arrhythmia.
The purpose of the study is to determine if DE-MRI is useful to guide mapping of ventricular arrhythmias in patients with non-ischemic cardiomyopathy.
Scar tissue was identified by DE-MRI in 13 out of 28 patients. Characteristics of these 13 patients were as follow. Patients had either sarcoidosis (n = 3) or dilated cardiomyopathy (n = 10). They either had a single focus on DE-MRI (n = 5) or multifocal disease (n = 8). The ventricular arrhythmia were VT (n = 9) or PVC (n = 4). The distribution was predominantly endocardial (n = 5), midmyocardial (n = 4), epicardial (n = 2) and transmural (n = 2). On the electroanatomic map, there was always low voltage present and matching the endocardial or epicardial surface displaying DE on MRI. The size of the endocardial scar on DE-MRI correlated well with the size of the endocardial scar defined by voltage mapping (45+-14 cm2, R = 0.94, p < 0.0001 with cutoff of 1.5 mV). All patients with inducible VT or sustained VT had evidence of DE on MRI. In all patients with DE on MRI where a critical site for the arrhythmia could be identified, this critical site was confined to the scar tissue.
DEMRI in patients without prior infarctions can help to identify the arrhythmogenic substrate; furthermore it helps to plan an appropriate mapping and treatment strategy.
This article is published under license to BioMed Central Ltd.