Impairment of BMIPP accumulation at junction of ventricular septum and left and right ventricular free walls in hypertrophic cardiomyopathy

Myocardial scintigraphy using I-123-15-(p-iodophenyl)-3-(R,S)-methylpentade canoic acid (BMIPP) reveals a high incidence of reduced accumulation of the tracer in patients with hypertrophic cardiomyopathy (HCM). This defect is thought to reflect impairment of myocardial fatty acid metabolism. in this study, the distribution of BMIPP defects was characterized and correlated w ith the clinical features of patients with HCM, Methods: Thirty patients wi th asymmetric septal hypertrophy (ASH) were examined. Regional BMIPP accumu lation was evaluated. Each region was normalized to the accumulation in the nonhypertrophic lateral region, which was represented as 100% on each bull 's-eye map. The corresponding thallium accumulation for each region was the n used to correct for the partial-volume effect. Results: BMIPP accumulatio n was significantly less in the septal portion of the anterior wall (As), t he septal portion of the posterior walt (Ps) and the apex than in the later al segments. BMIPP defects were significantly more frequent in the As, Ps a nd apical segments (20.0%, 20.0% and 33.3%, respectively) and were present in the As or Ps segments in 8 patients (27%). The patients with BMIPP defec ts in the As or Ps segments had a more frequent family history of HCM or su dden death and severe cardiac dysfunction. Conclusion: BMIPP defects occur predominantly in the As and Ps segments in some patients with ASH, which is often associated with severe cardiac dysfunction. The distribution of BMIP P detects may contribute to the classification of HCM and the assessment of its severity.