Quantitative evaluation of right ventricular myocardial blood flow using dynamic CZT SPECT imaging in patients with pulmonary arterial hypertension / 中华核医学与分子影像杂志

ABSTRACT

Objective:To establish SPECT quantitative method for assessment of right ventricular myocardial blood flow (MBF) and investigate the relationship between right ventricular MBF and pulmonary hemodynamics in patients with pulmonary arterial hypertension.Methods:From January 2018 to June 2019, 14 patients (13 females, 1 male; age (30.9±13.5) years) in Fuwai Hospital with pulmonary arterial hypertension related to congenital heart disease (PAH-CHD), whose right ventricular function were preserved, were retrospectively analyzed in this study. All subjects underwent dynamic SPECT myocardial perfusion imaging using cadmium-zine-telluride (CZT) SPECT. Full physical correction was applied for imaging reconstruction. One-tissue two compartmental model was used for kinetic analysis and the spill-over effect from right ventricular blood pool to right ventricular myocardium was considered into the correction, thus right ventricular MBF and left ventricular MBF was calculated. Right heart catheterization was performed within one week after SPECT imaging to evaluate the pulmonary hemodynamic parameters, and the right ventricular end-diastolic dimension (EDD) was measured by transthoracic echocardiography. Correlations between the MBF and other parameters were analyzed with Pearson correlation analysis.Results:The right ventricular MBF was (0.70±0.19) ml·min -1·g -1, which was significantly correlated with mean pulmonary artery pressure ((68.64±18.18) mmHg (1 mmHg=0.133 kPa); r=0.716, P<0.05) and pulmonary vascular resistance ((14.10±7.81) Wood units; r=0.768, P<0.05). The right ventricular MBF was also significantly correlated with right ventricular EDD ((32.00±7.75) mm; r=-0.624, P<0.05). Meanwhile, there was no significant relationship between left ventricular MBF and hemodynamic parameters ( r values from -0.350 to 0.310, all P>0.05). Conclusions:A method using SPECT to quantitively measure right ventricular MBF in patients with PAH-CHD is preliminarily established. Right ventricular MBF is increased with the increased pulmonary arterial pressure and pulmonary vascular resistance in patients with PAH-CHD.