Assessment of the functional state of the right ventricle by radionuclide tomoventriculography

: The aim of this work was to evaluate the potential of radionuclide tomoventriculography (RTVG) for the study of the functional state of right ventricle (RV) in patients with thromboembolism of branches of the pulmonary artery (TEPA) or ventricular arrhythmias. A total of 96 patients were admitted for examination to the clinics of Research Institute of Cardiology, Siberian Division of Russian Academy of Medical Sciences in 2006-2008. They were divided into 3 groups. Group 1 (n = 40) included patients of mean age 62 +/- 11 years with non-massive TEPA, group 2 (n = 15) patients with coronary heart disease NYHA class I-II (50 +/- 9 years), group 3 (n = 4) children and adolescents 13.2 +/- 3.7 years with ventricular extrasystole and/or monomorphic ventricular tachycardia. All patients were examined by ECG-synchronized RTVG. The study showed that this method can be used to efficaciously determine volume characteristics of right ventricle, ejection fraction, relationship between fast and slow filling phases, and intreventricular dyssynchronism. The functional ability of the right side of the heart in patients with minor lesions in the pulmonary vasculature should be regarded as a sign of acute thromboembolism and marked systole-diastolic dysfunction of right ventricle (under similar conditions) as a manifestation of chronic post-thromboembolic hypertension. The number of areas of asynchronous myocardial contractions and the degree of intraventricular dyssynchronism detected by RTVG positively correlate with the degree of contractile dysfunction of right ventricle. Scintiographic signs of intraventricular dyssynchronism suggest predominance of contractile heterogeneity of right ventricle over physiological one.