Abstract 10975: Prediction of Major Adverse Cardiac Events in Patients with Hypertrophic Cardiomyopathy by Quantitative Late Enhancement Volume in Left Ventricular Myocardium by Cardiac Magnetic Resonance
Purpose: To predict major adverse cardiac events (MACE) in patients with hypertrophic cardiomyopathy (HCM), we measured focal late enhancement volume (LEV) in left ventricular myocardium (LVM) by cardiac magnetic resonance (MR) quantitatively and followed patients for a median of 21 months.
Material and methods: 30 consecutive subjects with HCM (20 males, 65.8±11.8 years old, Maron HCM type 1, 1; type 2, 7; type 3, 10; type 4, 4; and type 5, 8) who underwent cardiac MRI (1.5T Intra achieva) were recruited and followed for a median of 20.8±12.6 months. Cardiac MR was acquired 15 minutes after injection of Gadopentetate dimeglumine for detecting LEV in LVM quantitatively, and the optimal cut off value of LEV was determined based on Receiver Operating Curved (ROC) analysis for prediction of MACE. Using optimal cut off value, we compared risks of MACE between groups with high and low LEV using a Kaplan Meier analysis.
Result: MFs were detected in 25 patients, and LEV was 35.7±26.7 cm3. Three (10%) had MACE, and their LEV (68.8±29.2cm3) was significantly greater than in subjects without MACE (32.0±24.3cm3; p<0.05). According to ROC analysis, at a cutoff of 49.8cm3, sensitivity and specificity for detection of MACE were 100% and 81.5%, respectively. HCM subjects were then divided into two groups on the basis of LEV ≥ 49.8cm3 and <49.8cm3, regarded as optimal cut-off value. MACE was observed more frequently in subjects with LEV ≥ 49.8cm3 (37.5%) than in those with LEV <49.8cm3 (0%; p=0.02) during observation period. A significant difference between the subjects with LEV ≥ 49.8cm3 and <49.8cm3 was also seen at each time point and when the whole period of follow up was compared with a Kaplan Meier analysis and log rank test (p<0.01). Inter observer variability of LEV was evaluated by two observers and its Pearson's correlation coefficient was 0.77 (p<0.05).
Conclusion: Risk of MACE was significantly higher in subjects with LEV ≥ 49.8cm3 than in those with LEV <49.8cm3 following a median of 21 months.
- © 2011 by American Heart Association, Inc.