Abstract 21323: Myocardial Inflammation is Associated with Reduced Left Ventricular Function in Clinically Suspected Idiopathic Dilated Cardiomyopathy - A Cardiovascular Magnetic Resonance Study
Background: It is suggested that an inflammatory response may trigger the development of idiopathic dilated cardiomyopathy, however, the incidence and direct relationship between inflammation and LV function in iDCM remain poorly understood. Cardiac MRI allows for visualization of myocardial inflammation using early enhancement (EE) imaging. We applied EE in iDCM to determine the incidence of myocardial inflammation, as well as its relation to LV function.
Methods: 26 patients (17 males, age 44±14 years old) were referred to for iDCM following strong clinical suspicion. Standard CMR imaging procedures for the assessment of LV function and EE were utilized. EE images were acquired before and early after (over 4 minutes) Gd-DTPA 0.1ml/kgBW contrast injection using T1-weighted images. For EE images, myocardial signal intensity was normalized to skeletal muscle generating a ratio that had to be greater than or equal to 4 to be considered positive for inflammation.
Results: Eighteen patients (69%) presented with evidence for EE. Patients with elevated EE had significantly dilated left ventricles and globally reduced ventricular function: LVEDVI (167.1±47.8 ml/m vs. 111.9±28.6 ml/m, p=0.006) and LVESVI (130.9±48.0 ml/m vs. 57.3±17.3 ml/m, p<0.001) were increased, while LVSVI (36.2±14.2 ml/m vs. 55.6±13.6 ml/m, p=0.005), LVEF (23.3±10.6% vs. 49.1±5.49%, p<0.001), and CI (2.26±0.64 l/min/m2 vs. 3.15±0.51 l/min/m2, p=0.002) were reduced.
Discussion: Using CMR-based EE as a marker of myocardial inflammation, we provide first evidence for a high incidence of inflammation in patients with iDCM. The extent of myocardial enhancement was directly related to reduced ventricular function. CMR-based assessment of myocardial inflammation may be utilized as a biomarker for patient prognosis and guide medical therapy to target patients with active myocardial inflammation.
- © 2010 by American Heart Association, Inc.