Effects of rest and exercise on cardiac blood volume determinations.

Aim: The purpose of this study was to investigate the changes in blood activity during rest, exercise and recovery, and to assess its influence on left ventricular (LV) volume determination using the count-based method requiring blood sampling.

Methods: Forty-four patients underwent rest-stress radionuclide ventriculography; Tc-99m-human serum albumin was used in 13 patients (Group I), red blood cells was labeled using Tc-99m in 17 patients (Group II) in vivo, and in 14 patients (Group Ill) by modified in vivo/in vitro method. LV volumes were determined by a count-based method using corrected count rate in blood samples obtained during rest, peak exercise and after recovery.

Cardiovascular effects of thyroxine in combination with methimazole in premenopausal female Graves' disease patients: case-control study.

Aim: To evaluate cardiovascular consequences of combined treatment in Graves' disease patients with addition of thyroxine (LT4) to antithyroid drugs in doses sufficient to suppress serum thyrotropin (TSH) levels below normal.

Methods: Eleven premenopausal female patients who reached subnormal TSH levels (<0.3 microIU/mL) under the combined therapy were evaluated by equilibrium radionuclide ventriculography at rest, and during the peak stage of fixed moderate exercise workload (75W) initially at diagnosis and after at least 8 months of stable euthyroidism, as judged by peripheral free thyroxine and triiodothyronine.

Worsening of left ventricular diastolic function during long-term correction of anemia with erythropoietin in chronic hemodialysis patients--an assessment by radionuclide ventriculography at rest and exercise.

We studied the effect of correction of anemia with erythropoietin on left ventricular systolic and diastolic function at rest and exercise in 17 chronic hemodialysis patients by means of maximum exercise testing and equilibrium gated radionuclide angiocardiography on three occasions: 1) initial--before erythropoietin administration, 2) intermediate--at the time when the target hemoglobin level reached 100 g/l, and 3) long-term--after 12 months of therapy. After correction of anemia, the patients showed a significant improvement in their response to exercise regarding maximal work load achieved, exercise duration and recovery time. Ejection fraction and peak ejection rate remained unchanged during therapy.

Cor triatriatum dextrum--an unusual variant of triatrial heart.

The present report describes a rare case of triatrial heart, cor triatriatum dextrum in a 31-year-old woman in whom the anomaly was incidentally detected by radionuclide angiocardiography. Subsequent assessment with two-dimensional echocardiography and right heart catheterization confirmed the presence of a membrane subdividing the right atrium into two distinct chambers. To the best of our knowledge, this is the only case in which this cardiac anomaly was demonstrated by radionuclide technique.