Left ventricular volumes by gated equilibrium radionuclide angiography: a new method.

Abstract

To compare radionuclide end-diastolic (EDV) and end-systolic (ESV) volumes with angiographic volume, we studied 52 patients with equilibrium radionuclide angiography using 99mTc-human serum albumin within 48 hours of contrast angiography. Each RR interval was divided into 20--28 equally timed frames and a time-activity curve generated. End-diastolic counts were taken at the early peak of the curve and end-systolic counts at its nadir. Counts were divided by the total number of processed heart beats and normalized for: 1) dose per body surface area; 2) plasma volume; and 3) counts/ml of plasma. A cardiac phantom was developed and serial volumes were studied using a normalization factor. Radionuclide values were expressed as dimensionless units and compared with either biplane angiographic volumes (in the patient studies) or known phantom volumes. Good correlations were obtained with methods 1 and 2 in 35 patients (r greater than 0.84), but the best correlation was obtained in 17 patients when normalization for counts/ml of plasma was used (r = 0.98; y = 0.255 x -0.121). The standard error of the estimate (SEE) was +/- 11.5 ml for EDV and +/- 7.3 ml for ESV. The phantom study also showed an excellent correlation (r = 0.99), with a SEE of +/- 6.5 ml. We conclude that a radionuclide method independent of geometric assumptions can be used to estimate left ventricular volume in man.

Effect of exercise on erythrocyte count and blood activity concentration after technetium-99m in vivo red blood cell labeling.

“…Exercise duration, reason for exercise termination, maximal heart rate, and percent change in blood radioactivity concentration and in erythrocyte count are listed in table 1 Abbreviations: MR = mitral regurgitation; CAD -coronary artery disease; AVR = status after aortic valve replacement; CP = atypical chest pain syndrome; AR = aortic regurgitation; nitr = nitrates; asp = aspirin; lidof = lidoflazine; prop = propranolol; thia = thiazide diuretic; fur = furosemide; CHF = congestive heart failure.…”

A Study on Comparison of Cardiac Ejection Fraction Values Measured in Myocardium SPECT and Cine MRI

“…Methods to measure the function include angiocardiography, cardiovascular ultrasonography, radioisotope angiography and MRI [8][9][10][11].…”

Evaluation of relationship between myocardial contractile state and left ventricular function in patients with aortic regurgitation.

“…'9 Left ventricular volumes were determined by a nongeometric technique. 24 25 To compensate for differences in the amount of radioactivity injected, a peripheral venous blood sample was drawn immediately after each imaging session, counted at a distance of 8.5 cm by the same collimator, and corrected for background in the field. With knowledge of the transpired time and half-life of 99mTc, the activity in blood at the midpoint of each imaging session was calculated.26 Attenuated radionuclide left ventricular volumes were derived from a standard formula.24' 25 In our laboratory, the nongeometric radionuclide estimation of absolute left ventricular end-diastolic volume has been validated against the value obtained with contrast angiography in which angiographic end-diastolic volume -3.77 x attenuated radionuclide enddiastolic volume + 9.…”