Prognostic Value of CMR and FDG-PET in Patients with Myocarditis

Presenting Author(s)

• 

  Chaitanya Rojulpote, MD

  Fellow
  Brigham and Women's Hospital
  Boston, Massachusetts, United States

Primary Author(s)

• 

  Chaitanya Rojulpote, MD

  Fellow
  Brigham and Women's Hospital
  Boston, Massachusetts, United States

Co-Author(s)

• SH

  Stephen J. Hankinson, MD

  Fellow
  Brigham and Women's Hospital, United States
• 

  Michael M. Givertz, MD

  Medical Director, Heart Transplant and Mechanical Circulatory Support
  Brigham and Women's Hospital, Harvard Medical School
  Brigham and Women's Hospital
  Boston, Massachusetts, United States
• JH

  Jon Hainer

  Business Systems Analyst Principal
  Brigham and Women's Hospital, United States
• 

  Sharmila Dorbala, MD, MPH

  Director, Nuclear Cardiology
  Brigham and Women's Hospital
  Boston, Massachusetts, United States
• 

  Raymond Y. Kwong, MD, MPH, FSCMR

  Professor of Medicine
  Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
  Chestnut Hill, Massachusetts, United States
• RB

  Ron Blankstein
• MD

  Marcelo Dicarli

  Cardiovascular Imaging Program, Departments of Radiology and Medicine, Brigham and Women's Hospital, United States
• SD

  Sanjay Divakaran, MD, MPH

  Associate Chief and Clinical Director
  Brigham and Women's Hospital, United States

Background: Cardiac magnetic resonance (CMR) is a powerful diagnostic and prognostic tool in evaluating patients with suspected myocarditis. The presence of perfusion/metabolism mismatch via fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET) is associated with worse outcomes in patients with cardiac sarcoidosis. We aimed to study if perfusion/metabolism mismatch is associated with worse outcomes in patients with a different inflammatory cardiomyopathy, myocarditis.


Methods: From a database registry of 1,646 patients at the Brigham and Women’s Hospital who underwent FDG-PET for suspected inflammatory cardiomyopathy, we identified patients who met the following criteria: 1) had a primary diagnosis of myocarditis, 2) had both FDG-PET and CMR, 3) had abnormal CMR, defiend as presence of focal late gadolinium enhancement suggestive of myocarditis, 4) had no evidence of cardiac or extracardiac sarcoidosis via imaging or biopsy. Using these criteria, we identified 140 patients (58.1±13.7, 69% male, LVEF 51.4±12.4). Patients were stratified based on the presence or absence of perfusion/metabolism mismatch via FDG PET-CT. Major adverse cardiovascular events (MACE) were defined as a composite of cardiac transplant or death. Kaplan-Meier curve and cox-proportional hazard ratios were utilized for analysis.

Results: Perfusion/metabolism mismatch was present in 30 patients (age 61.6 ± 8.9, 67% male, LVEF 48.2 ± 14.9) and absent in 110 patients (age 57.1±14.6, 70% male, LVEF 52.3±11.5). In an unadjusted analysis, patients with perfusion/metabolism mismatch had a trend toward worse MACE (HR: 3.43, 95% CI: [0.92, 12.8], p=0.066; Figure 1A). However, there was no association after adjustment for resting left ventricular ejection fraction, sex, and age (HR: 2.36, 95% CI 0.563, 9.53, p=0.244, Figure 1B).

Conclusion: Among patients with suspected myocarditis who had an abnormal CMR, perfusion-metabolism mismatch via FDG-PET was not found to be an incremental prognostic indicator of adverse outcomes. Future studies with larger sample sizes are warranted to further investigate the potential prognostic utility of complementary advanced imaging in this patient population.

Baseline Characteristics Stratified by Imaging of Sequential CMR/PET

Characteristic	EarlyN = 36	LateN = 121	p-value
Age (years)	60.0 ± 12.0	56.8 ± 14.1	0.3
Race			0.027
Black	5 (14%)	10 (8.3%)
Other	5 (14%)	4 (3.3%)
White	26 (72%)	107 (88%)
Gender	22 (61%)	85 (70%)	0.3
BMI	30.2 ± 5.5	29.9 ± 6.0	0.4
History of Pacemaker	0 (0%)	7 (5.8%)	0.4
History of AICD	2 (5.6%)	30 (25%)	0.012
Diabetes mellitus	5 (14%)	8 (6.6%)	0.2
Coronary artery disease	0 (0%)	5 (4.1%)	0.6
RestLVEF	51.0 ± 15.1	52.1 ± 11.5	0.8
CMR			0.2
Negative	2 (5.6%)	7 (5.8%)
Nonspecific	4 (11%)	4 (3.3%)
Present	30 (83%)	110 (91%)
PET			0.3
Abnormal	20 (56%)	50 (41%)
Negative	12 (33%)	51 (42%)
Nonspecific	4 (11%)	20 (17%)

Figure 1A: Kaplan-Meier survival curve depicting mismatch vs no mismatch
Figure 1B: Forest plot depicting an adjusted cox-proportional hazard ratio