[Image fusion of gated-SPECT and CT angiography in coronary artery disease. Importance of anatomic-functional...

Area of Science:

• Cardiovascular Imaging
• Nuclear Cardiology
• Interventional Cardiology

Background:

• Acute coronary syndrome (ACS) without ST elevation requires accurate risk stratification and identification of the culprit lesion.
• Myocardial perfusion gated SPECT is a key tool for assessing ischemia, but attributing defects to specific coronary arteries can be challenging.
• Coronary CT angiography (CCTA) provides detailed anatomical information of coronary arteries.

Observation:

• A 77-year-old patient presented with ACS without ST elevation and was initially assessed with myocardial perfusion gated SPECT, showing mild inferior ischemia.
• Despite optimized medical therapy, the patient experienced persistent exertional dyspnea, prompting CCTA.
• CCTA revealed severe lesions in the proximal right coronary artery (RCA).

Findings:

• SPECT-CT fusion imaging successfully correlated the perfusion defect with the posterior descending artery originating from the RCA.
• The fusion images were crucial in differentiating the RCA from the circumflex artery as the cause of ischemia in this co-dominant coronary system.
• This case demonstrates the utility of SPECT-CT fusion in complex coronary artery anatomy.

Implications:

• SPECT-CT fusion imaging can improve diagnostic accuracy in cases where the culprit artery is ambiguous.
• This technique facilitates more targeted treatment strategies for patients with coronary artery disease.
• Enhanced visualization through image fusion supports clinical decision-making in cardiology.