(123)I-BMIPP fatty acid analogue imaging is a novel diagnostic and prognostic approach following acute myocardial infarction

Biswas SK, Sarai M, Hishida H, Ozaki Y
Correspondence: Dr Shankar Kumar Biswas, biswas_70@yahoo.com

ABSTRACT
Fatty acid oxidation is the most efficient mode of myocardial energy production which requires a large amount of oxygen. Thus, alteration of fatty acid oxidation is considered to be a sensitive marker of ischaemia and myocardial damage. ¹²³I-BMIPP (¹²³I-ß-methylp-iodophenylpentadecanoic acid) is a newly-investigated single-photon branching free fatty acid radiopharmaceutical with slow metabolism; thus, it is well-suited for single-photon emission computed tomography (SPECT). Assessment of fatty acid metabolism by radionuclide techniques has a potential role for the early detection of myocardial ischaemia and the assessment of the severity of ischaemic heart disease. Although stable patients with a healed myocardial infarction may have a relatively good prognosis, risk stratification in the predischarge period should be valuable for deciding upon appropriate management. In this respect, the presence of discordant BMIPP uptake relative to 201Tl perfusion appears to be the best predictor of future cardiac events among all other cardiovascular imaging modalities. Since discordant BMIPP uptake correlates well with redistribution on stress 201Tl imaging and perfusion-metabolism mismatch on positron emission tomography, it is considered that such BMIPP and 201Tl discordance may identify a high-risk subgroup among patients with acute myocardial infarction. A BMIPP scan may reflect prior severe ischaemia after recovery of perfusion, the so-called “ischaemic memory”. Gated BMIPP SPECT has been recently introduced for simultaneous assessment of myocardial metabolism and ventricular function. Such a new technique seems to be valuable for a better understanding of the pathophysiological state of heart failure and cardiomyopathy.

Keywords: acute myocardial infarction, ß-methyl-p-iodophenylpentadecanoic acid scan, fatty acid metabolism, ischaemic memory
Singapore Med J 2009; 50(10): 943-948