The Role of Radionuclide Ventriculography in Diagnosing of Right Ventricle Myocardial Infarction

Full text: Purpose: The purpose of the paper is to use radionuclide ventriculography (RNV) in order to study the alteration of the cardiac performance of the right ventricle and the occurrence of right ventricular dyssynergy in patients with lower right ventricle myocardial infarction. Material and Methods: RNV was performed with a SPECT ADAC camera with a single head. In order to perform the RNV, i.v. pyrophosphate was first administered, followed by a 30- minute break (so that pyrophosphate could attach to the erythrocytes) and the injection of 99mTc that attaches instantly to the pyrophosphate-erythrocyte complex. The image acquisition was carried out in the OAS 300C incidence with a 10-150C caudal inclination so that SIV could be properly visualized. The parietal kinetics can be followed during one full cardiac cycle (divided into 16 equally-long sequences) by in vivo marking of the erythrocytes with 99mTc and highlighting the volume of the right and left ventricular cavities while the parameters of systolic and diastolic performance of the two ventricles can be calculated from the radioactivity-time curves of the right and left ventricle. Thirty patients, 27 males and 3 females, with lower myocardial infarction were included in the study. The patients' age ranged from 29 to 72 years. The following parameters were studied: FEVS, FEVD, VMU, VMG, tVMG. Normal values: FEVS N>50%; FEVD N>45%; VMU(PFR)N>2.5VTD/s; VMG(PER) N>- 2.5VTD/s; tVMG(tPER)N<180ms. Results: Thirty patients (100%) presented dyssynergy or decreased FE,VMG,VMU in the right ventricle. The dysfunction of the right ventricle was interpreted as being necrosis a complication of the lower myocardial infarction. Conclusions: RNV is an appropriate technique for diagnosing right ventricular myocardial infarction as a complication of lower myocardial infarction. The alteration of the systolic and diastolic function of the right ventricle, as well as the occurrence of right ventricular dissynergy, represent diagnosis parameters for right ventricle myocardial infarction. (author)