Thallium-201 myocardial perfusion imaging in myocarditis

Area of Science:

• Cardiology
• Nuclear Medicine
• Diagnostic Imaging

Background:

• Myocarditis diagnosis can be challenging, often presenting with non-specific symptoms.
• Electrocardiographic abnormalities and elevated cardiac enzymes are common in myocarditis.
• Coronary angiography is typically normal in myocarditis, ruling out significant coronary artery stenosis.

Observation:

• Thallium-201 (TI-201) myocardial perfusion imaging was conducted on six patients with clinically confirmed myocarditis.
• Patients exhibited electrocardiographic changes and elevated serum cardiac enzymes.
• Resting TI-201 images were reviewed by three independent observers.

Findings:

• Focal perfusion defects were identified in 50% of the cases (three out of six patients).
• Among those with defects, two patients showed multiple perfusion abnormalities.
• Emission computed tomography (ECT) with TI-201 effectively visualized multifocal lesions in one patient.
• No significant perfusion defects were observed in the remaining three patients.

Implications:

• Myocarditis should be recognized as a potential cause of perfusion defects on TI-201 myocardial imaging.
• TI-201 imaging, particularly with ECT, can aid in the detection and characterization of myocardial involvement in myocarditis.
• These findings highlight the utility of nuclear imaging in the diagnostic workup of suspected myocarditis.