Abstract 14205: Determination of Desirable Periods on Performance of (18) F-Fluorodeoxyglucose Positron Emission Tomography after Onset of Clinically Suspected Acute Myocarditis for Detecting Inflammatory Left Ventricular Myocardium Compared with Endomyocardial Biopsy Findings
Purpose: To determine desirable periods on performance of (18) F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in subjects with suspected acute myocarditis (AM) for detection of active inflammatory left ventricular myocardium (AILVM) compared with endomyocardial biopsy (EB) findings.
Methods: Retrospective analysis of 53 consecutive subjects (35 males, mean age 50± 16yrs) with suspected clinical AM who underwent both FDG-PET (Advance NXi) (performed at mean 44±31 days after onset of suspected AM) and EB (performed at mean 37±22 days after onset of suspected AM) to detect AILVM. Subjects were fasted for 6 hrs before FDG PET. 21 subjects underwent FDG PET before EB.
Results: Final diagnoses were AM 15 subjects, post myocarditis 8 subjects, dilated cardiomyopathy 9 subjects, hypertrophic cardiomyopathy 3 subjects, hypertensive heart disease 4 subjects, unidentified cardiomyopathy 9 subjects and other 5 subjects. Of the 53 subjects, there were positive concerns in 13 and 15 about AILVM on FDG PET and EB, respectively. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and agreement of FDG-PET compared with EB for detecting AILVM were 66.7, 92.1, 76.9, 87.5 and 84.9%, respectively in all 53 subjects. These were then divided into four groups on the basis of performance of FDG-PET 1-14, 15-29, 30-44, 45-59, and 60- days after onset of suspected AM. Sensitivity, specificity, PPV, and NPV of FDG-PET compared with EB for detecting AILVM were best when FDG-PET was performed at 1-14 days after onset of suspected AM, where these values were all 100% (prevalence of AILVM on EB was 33.3%). However, these values worsened when FDG-PET was performed more than 15 days after onset of suspected AM (see Figure).
Conclusions: FDG-PET showed excellent agreement with EB in detecting AILVM in subjects with clinically suspected active AM. After onset of suspected AM, if FDG PET was performed <15 days, high accuracy would be expected compared with EB.
- © 2012 by American Heart Association, Inc.