Biswas SK, Sarai M, Toyama H, Yamada A, Harigaya H, Naruse H, Hishida H, Ozaki Y
Correspondence: Dr Shankar Kumar Biswas, biswas_70@yahoo.com
ABSTRACT
Introduction Myocardial scintigraphy with 123I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (123I-BMIPP) is used to evaluate impaired fatty acid metabolism. B-type natriuretic peptide (BNP), which is secreted by the ventricular myocardium on stretching and/or pressure overload, is a useful cardiac biomarker. This study aimed to evaluate the usefulness of 123I-BMIPP imaging and serum BNP levels in patients with heart failure (HF).
Methods 113 patients with HF were enrolled. There were 68 patients with ischaemic heart disease (IHD) and 22 with overt HF. Cardiac scintigraphy was performed 7 ± 3 days after admission, and heart-to-mediastinum (H/M) count ratios on early and delayed images and washout rates (WR) of 123I-BMIPP were recorded. Serum BNP levels were recorded on the day of 123I-BMIPP imaging. The ejection fraction (EF) was calculated just before cardiac scintigraphy using conventional echocardiography.
Results The mean BNP level and EF were 282 pg/mL and 47%, respectively, with significant correlation between them. The mean H/M count ratios on early and delayed images were 2.29 and 1.93, respectively, showing significant positive correlations with EF (r = 0.31, p = 0.0006). The WR was significantly correlated with EF (r = -0.36, p < 0.0001) and BNP levels (r = 0.33, p = 0.003), and mean WR was significantly higher in patients with overt HF compared to those without (p < 0.001). Patients with IHD had significantly higher EFs than those with non-IHD (p = 0.03).
Conclusion The evaluation of impaired myocardial metabolism using 123I-BMIPP scintigraphy and serum BNP levels appears to be useful for the evaluation of severity of HF.
Keywords: B-type natriuretic peptide, cardiac scintigraphy, heart failure, myocardial fatty acid metabolism
Singapore Med J 2012; 53(6): 398–402