MYOCARDIAL DYSFUNCTION AND DEPRESSED FATTY-ACID METABOLISM IN PATIENTS WITH CYANOTIC CONGENITAL HEART-DISEASE

Background, Myocardial contractile dysfunction has been frequently obs erved in adolescents or adults with cyanotic congenital heart disease, Impaired energy metabolism may be present in such dysfunctional myoca rdium. Methods and Results, To evaluate the findings of myocardial fre e fatty acid metabolism, and its relations to ventricular wall motion and myocardial perfusion in cyanotic congenital heart disease, we perf ormed a combined study of iodine 123-labeled 15-(p-iodophenyl)-3-(R,S) -methylpentadecanoic acid (BMIPP) scintigraphy, thallium scintigraphy, and contrast cineangiography in seven patients with single right or l eft ventricle, The results showed that wall motion was reduced in 17 o f 35 ventricular segments (49%), which were mostly identical in locati on to decreased BMIPP uptake, The severity of BMIPP uptake deficit cor related positively with the degree of impairment of wall motion, On th e other hand, thallium uptake was abnormal only in 5 of 35 segments (1 4%), and the severity of the perfusion defect did not correlate with t he degree of wall motion abnormality, Conclusions, Contractile dysfunc tion in cyanotic heart disease was primarily linked to impaired free f atty acid metabolism rather than to myocardial scar as represented by perfusion defect on thallium imaging.