A new scintigraphic method for determining left ventricular volumes.

A new scintigraphic count-based method for measuring absolute left ventricular volumes is presented. It is a fast and simple technique that allows geometrical assumptions to be avoided and is free of radiation attenuation corrections. This method requires the acquisition of an image of the left ventricle in the right anterior oblique projection and the collection of gated blood pool images in the left anterior oblique projection. To assess the accuracy of the method scintigraphic stroke volumes were compared with those derived from thermodilution measurements during cardiac catheterization in 20 subjects, and to assess its precision the technique was applied to phantom data of known radionuclide volumes. Excellent correlations were found between the scintigraphic and both the thermodilution (r = .98) and phantom data (r = .99). The reproducibility (r = .97) of results was investigated by repeating data acquisition and analysis for 15 subjects on two different days, and the interobserver variability (r = .97) of the method was studied by having two computer operators calculate volumes for the same patient data for 20 randomly selected studies.

Coronary artery fistula: estimation of shunt using 99m Tc-albumin particles.

A 60-year-old man presented with complaints on angina pectoris and was found to have a coronary artery fistula between his left main truck and main pulmonary artery. Particles of 99m Tc-Albumin were injected in the ostium of the left coronary artery, and differential radioactive counts were injected in the ostium of the left coronary artery, and differential radioactive counts were obtained over both lung fields and myocardium. The degree of left to right shunt was calculated at 56% of total left coronary artery flow. The patient underwent ligation of the fistula without any complications. This case report represents a new application of myocardial radioisotopic scanning.

Familial myxomas in four siblings.

Familial myxomas of the heart are very rare, with only two previous reports noted in the literature. This report documents four siblings with myxomas, and three of these patients had two or more myxomas. One sibling had four myxomas excised. The clinical findings, history, examination, and surgical treatment are described.

Myocardial scintigraphy. Post-Vineberg study.

In order to assess myocardial perfusion of Vineberg implants, tracer particles (99mCc and 131I-MAA) were injected into the internal mammary implants of 7 patients (6 years after the operation) after selective contrast visualization. The myocardial perfusion images were correlated with the internal mammary arteriographic findings. Of those patients with patent implants with communication, the myocardial scintigrams demonstrated even distribution of radioactive particles reflecting myocardial perfusion at the capillary or precapillary bed.

Radiation exposure to angiographer during coronary arteriography using the U arm image amplifier.

Radiation exposure to the angiographer was measured using thermoluminescent dosimeters (TLD), commercial film badges, and appropriate ionization survey meters. Data were collected during 47 coronary artery examinations with the lead overleaf. During a single coronary examination, the angiographer receives 0.9 mR to the lens and 2.8 mR to the hand. The calculated yearly exposure to the angiographer performing 10 examinations per week is 450 mR to the lens, 9% of the maximum permissible dose (MPD), and 1400 mR to the hand, 2% of the MPD. Exposure rates for the left anterior oblique (LAD) and right anterior oblique (RAO) projections during cine and fluoroscopy were taken at the position occupied by the angiographer. Scatter radiation is 5-10 times greater in the LAO projection. The second trial was monitored during 18 coronary artery examinations minus the lead overleaf. A significant decrease in radiation exposure was accomplished through the use of the lead overleaf.

Direct selective myocardial revascularization by internal mammary artery-coronary vein anastomosis.

In this report, we shall describe our work with retrograde coronary perfusion, first in mongrel dogs and then in 6 patients. The left internal mammary artery (LIMA) is anastomosed to the left anterior descending coronary vein (LADV) to provide myocardial perfusion. This procedure may be of great value in the treatment of patients who are not suitable candidates for direct coronary bypass grafting, i.e., those who have diffuse atherosclerosis, with poor or no runoff of the left anterior descending coronary artery (LADA),but who have satisfactory left ventricular contraction.