Role of ¹²³I-BMIPP and serum B-type natriuretic peptide for the evaluation of patients with heart failure

<p><b>INTRODUCTION</b>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).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>

The accuracy and optimal slice thickness of multislice helical computed tomography for right and left ventricular volume measurement / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Multislice helical computed tomography (MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy of ventricular volume as measured by MSCT.</p><p><b>METHODS</b>Fourteen human left ventricular (LV) and 15 right ventricular (RV) casts were scanned by MSCT. A series of LV and RV short-axis images were reconstructed later with slice thickness of 2.0 mm, 3.5 mm, 5.0 mm, 7.0 mm, and 10.0 mm. Ventricular volume was calculated by the multislice tomographic Simpson's method. True LV and RV cast volumes were determined by water displacement.</p><p><b>RESULTS</b>Both calculated LV and RV volumes correlated highly with the corresponding true volumes (all r >0.95, P <0.01). But with slice thickness from 2.0 mm to 10.0 mm, MSCT scanning overestimated the corresponding true volume by (3.21 +/- 5.95) ml to (12.58 +/- 8.56) ml for LV and (10.22 +/- 8.45) ml to (23.91 +/- 12.24) ml for RV (all P <0.01). There was a very high correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements (r=0.998 and 0.996, P <0.01, respectively). However, when slice thickness was reduced to 5.0 mm, the overestimation for both LV and RV volume measurements became nonsignificant for slice thickness from 2.0 mm to 5.0 mm.</p><p><b>CONCLUSIONS</b>Both LV and RV volumes can be accurately estimated by MSCT. Thinner slice has more accurate calculated volume. However, 5.0 mm slice thickness is thin enough for an accurate measurement of LV or RV volume.</p>