Article Text
Abstract
Objective To determine the clinical and prognostic value of identifying metabolic abnormalities of myocardial fatty acid metabolism in idiopathic dilated cardiomyopathy using iodine-123 β-methyl-iodophenyl pentadecanoic acid (123I BMIPP).
Setting Cardiac care division in national hospital.
Patients 32 consecutive patients with idiopathic dilated cardiomyopathy in whom both 123I BMIPP and thallium-201 myocardial single photon emission computed tomography were performed.
Methods The uptake of each tracer was scored visually from 0 (normal) to 3 (defect) in 17 segments (eight basal, eight midventricular, and one apical). A total score for all 17 segments was compared with clinicopathological variables. Prognostic value of mismatches between the two tracers were also evaluated.
Results The123I BMIPP total score was correlated with pulmonary capillary wedge pressure (r = 0.68, p < 0.001), left ventricular end diastolic pressure (r = 0.65, p < 0.001), percentage fractional shortening at six months’ follow up (r = -0.58, p = 0.001), myocyte diameter (r = 0.66, p < 0.001), and percentage area of interstitial fibrosis (r = 0.69, p < 0.001) measured by morphometry in the biopsy specimens. During a mean (SD) follow up of 20 (11) months, deterioration of the New York Heart Association functional class was observed in 11 of the 32 patients; four of these died. Segments with a greater decrease in123I BMIPP than thallium-201 uptake (type B mismatching) were often observed in patients with deterioration (88/187, 29%v 58/357, 16%; p < 0.001).
Conclusions The extent of the abnormality of myocardial fatty acid metabolism in idiopathic dilated cardiomyopathy reflects the severity of haemodynamic deterioration and histopathological changes. Type B mismatching is one of the important prognostic indicators in idiopathic dilated cardiomyopathy.
- idiopathic dilated cardiomyopathy
- fatty acid metabolism
- β-methyl-iodophenyl pentadecanoic acid