Recurrent myocardial infarction with near-normal coronary angiogram and myocardial ischemia detected by Tc-99m SPECT and magnetic resonance perfusion imaging

✍ Scribed by Atiar M Rahman; Nabil Ahmad

• Publisher: Springer
• Year: 2003
• Tongue: English
• Weight: 178 KB
• Volume: 10
• Category: Article
• ISSN: 1071-3581
• DOI: 10.1016/s1071-3581(03)00430-6

✦ Synopsis

Introduction. The incidence of myocardial infarction (MI) with normal coronary arteries is extremely low (Ͻ1%). 1 This clinical entity often leads to a diagnostic dilemma, as the coronary angiogram does not correlate with the clinical scenario. We describe a patient who had large ST elevation MI with angiographically and hemodynamically near-normal coronary anatomy and physiology, respectively. To the best of our knowledge, this is the first report of a patient who had recurrent MI with magnetic resonance perfusion imaging showing myocardial injury but in whom no obstructive lesion were noted on repeated angiograms.

Case history. A 44-year-old man was seen at an outside hospital with acute chest pain associated with ST-segment elevation MI and elevated cardiac enzyme levels. His symptoms and anterior ST elevation resolved after intravenous thrombolysis. A transthoracic echocardiogram showed mildly depressed left ventricular function with apical hypokinesia. Cardiac catheterization performed 3 days later showed an approximately 30% mid-left anterior descending coronary artery stenosis and angiographically normal left circumflex and right coronary arteries (Figure 1). In the setting of angiographically insignificant coronary stenosis, the patient was treated conservatively and discharged taking the following: aspirin, nitrate, statin, ␤-blocker, and angiotensin-converting enzyme inhibitor. However, he presented 2 weeks later with non-ST-segment elevation MI.

For resolution of the clinical dilemma of recurrent MI in the presence of nonobstructive coronary artery disease (CAD), adenosine technetium 99m gated myocardial perfusion scanning with a 1-day rest-stress protocol was performed. It showed a large partially reversible perfusion defect in the anteroapical and lateral walls of the left ventricle (Figure 2) with akinetic apex. A