Gallium-67 scanning in Sjögren's syndrome: concise communication.

We performed gallium-67 scans in 12 patients with primary or secondary Sjögren's syndrome (SS). Salivary-gland uptake of gallium-67 was noted in four of five patients with primary SS. Pulmonary uptake was observed in ten of 12 patients. Chest radiographs were essentially normal in all patients, although 60% complained of significant dyspnea with exertion. The gallium-67 scan may prove to be a sensitive noninvasive diagnostic test for lung and mediastinal involvement by either primary or secondary SS, and for salivary-gland involvement in primary SS.

Visualization of atrial myocardium with thallium-201: case report.

An adult patient evaluated for cyanotic congenital heart disease was found to have pulmonary atresia with intact ventricular septum, hypoplastic right ventricle, and right atrial enlargement. Thallium-201 myocardial imaging before surgical correction showed thallium activity in the right atrium. Following the establishment of a conduit from the right atrium to pulmonary artery, the right-atrial thallium uptake was even more prominent.

Value of gallium-67 citrate scanning in Crohn's disease: concise communication.

A frequent problem in Crohn's disease is the distinction between exacerbated inflammation of the bowel, which can be treated medically, and intra-abdominal abscess, a common complication that requires surgical management. We present evidence that the gallium scan is of value in making this distinction. From a series of 11 studies, negative gallium scans correctly excluded abscess in over half. All patients were symptomatic at the time of the scan. Most patients with active Crohn's disease do not have abnormal gallium uptake and in these patients the gallium scan is useful to exclude the possibility of abscess.

Comprehensive evaluation of renal function in the transplanted kidney.

By means of a comprehensive renal function test based on the analysis of orthoidohippurate kinetics carried out 223 times in 86 renal transplatn patients, we have been able to separate clearly five clinical entities: normally functioning transplanted kidneys, acute tubular necrosis, cell-mediated rejection, humoral (chromin) rejection, and postrenal obstruction. Accurate prediction of the fate of the rejecting kidney can be made while still subclinical as much as a week before manifestations by other techniques are evident. Data on 22 donors studied 44 times are also presented. The comprehensive test consists of measurements of effective renal plasma flow (ERPF), sequential scintigraphy, calculations of excretory index (EI) (percent dose actually found in bladder and voided urine as a fraction of the percent dose expected at a given time after injection at the patient's specific ERPF), and residual urine volume. Formulas and regression equations for the calculation of ERPF, EI, residual urine, etc., are presented.

Use of blood-pool imaging in evaluation of diffuse activity patterns in technetium-99m pyrophosphate myocardial scintigraphy.

It has been suggested that diffuse Tc-99m pyrophosphate precordial activity may be due to persistent blood-pool activity in routine delayed views during myocardial imaging. To answer this question, we reviewed myocardial scintigrams recorded 60--90 min following the injection of 12--15 mCi of Tc-99m pyrophosphate for the presence of diffuse precordial activity, and compared these with early images of the blood pool in 265 patients. Diffuse activity in the delayed images was identified in 48 patients: in 20 with acute myocardial infarction and in 28 with no evidence of it. Comparison of these routine delayed images with early views of the blood pool revealed two types of patterns. In patients with acute infarction, 95% had delayed images that were distinguishable from blood pool either because the activity was smaller than the early blood pool, or by the presence of localized activity superimposed on diffuse activity identical to blood pool. In those without infarction, 93% had activity distribution in routine delayed views matching that in the early blood-pool images. The usefulness of the diffuse TcPPi precordial activity in myocardial infarction is improved when early blood-pool imaging is used to exclude persistence of blood-pool activity as its cause. Moreover, it does not require additional amounts of radioactivity nor complex computer processing, a feature that may be of value in the community hospital using the technique to "rule out" infarction 24--72 hr after onset of suggestive symptoms.

Incidence of new pulmonary perfusion defects after routine cardiac catheterization.

The incidence of pulmonary perfusion defects after routine cardiac catheterization was assessed in 57 patients by comparing ventilation-perfusion lung scans obtained before and 1 day after catheterization. Patients were prospectively randomized to two groups, one in which right heart catheterization was performed using an antecubital venous cutdown procedure and one in which the percutaneous femoral vein approach was used. Seven patients (12 percent) had new postcatheterization perfusion defects consistent with pulmonary emboli. These patients did not differ significantly from patients without new defects in clinical characteristics, duration of catheterization, hemodynamic variables or route of right heart catheterization. The data suggest that pulmonary embolism may be a more common complication of routine cardiac catheterization than previously appreciated.

Results of radionuclide assessment of cardiac function following transplantation of the heart.

Radionuclide assessment of ejection fraction was determined early and late postoperatively following cardiac transplantation in 16 patients. In 11 patients, ejection fraction was determined within 48 hours of an endocardial biopsy. There was no relationship between the severity of histologically evident rejection and the ejection fraction (Pearson correlation coefficient [r] = -0.11; p = 0.47). In 2 patients, severe graft fibrosis developed with consequent diminution in ejection fraction. There was no relationship between severity and duration of rejection or the amount of immunosuppression required to treat acute rejection and the development of graft fibrosis. The mean resting ejection fraction in 7 patients in follow-up ranging from 6 to 21 months after transplantation was 0.59 +/- 0.06 (standard deviation), and the mean exercise ejection fraction in 6 of these patients was 0.72 +/- 0.08. Radionuclide-determined ejection fraction is not predictive of rejection early after operation. During short-term late follow-up, systolic left ventricular function at rest and exercise has been retained at normal levels.

Maximizing the information from thallium studies.

The clinical role of maximizing the value of T1-201 scintigraphy, both at rest and during a graded exercise tolerance test, as well as variations on that theme, have been described. Technical aspects of scintigraphy have been reviewed in view of the many complex properties of this radionuclide, including photon detection and attenuation. Rest studies may be important in acute myocardial infarction to predict complications, survival, and reoccurrence. The potential for stress testing has been emphasized, as well as the apparent problems of such studies in patients at high-risk, such as those with definite angina and post-coronary by-pass surgery. A comprehensive approach to the complementary or exclusionary nature of T1-201 (or other potential myocardial perfusion imaging agents) and ventricular function analysis using radionuclide techniques will be left to the present and future seers, which, of course, hopefully include this author and his associates.

Rapid assessment of ventricular fibrillation thresholds during experimental infarction in the canine heart.

Sophisticated instrumentation is described which allows the rapid estimation of vulnerability of the ventricle to multiple responses and fibrillation with the classical technique described by Wiggers and Wegria. It seems particularly pertinent to the assessment of the significance of "R on T" type of ventricular extrasystoles in myocardial infarction. The thresholds to tachyarrhythmia were decreased by about 64% within 10 min of coronary occlusion and persisted at that level for 60-90 min, suggesting the usefulness of this model in assessing anti-fibrillatory drug regimes during the early evolutionary stage of myocardial infarction.

Antiarrhythmic anesthetic action I: the effect of halothane on canine intracardiac impulse conduction during sinus rhythm.

The effect of halothane on intracardiac impulse conduction was assessed in dogs before and after pharmacologic vagotomy. Impulse conduction was measured by anesthetic-related changes in the A-H and H-V intervals of the His bundle electrogram. Prior to vagotomy, both "light" and "deep" halothane prolonged the A-H interval significantly. Maximal A-H interval prolongations corresponded to the maximal decrease in heart rate with either dose of anesthetic. Following vagotomy, the A-H prolongation produced by light halothane was abolished and the prolongation produced by the deep level greatly reduced. Neither dose of halothane had a measurable effect on the H-V interval before or after vagotomy. In one animal in which the effects of increasing rates of atrial pacing were measured without the addition of halothane, the A-H interval lengthened with no measurable change in the H-V interval. In two dogs in which the heart rate was held near pre-halothane levels by atrial pacing, the A-H interval was slightly prolonged and the H-V interval unchanged during the administration of deep halothane. These studies indicate that during sinus rhythm: (1) halothane prolongs A-V impulse conduction, (2) that this effect is correlated with a concomitant decrease in heart rate, and (3) that these effects are largely dependent upon intact vagal innervation of the heart. During atrial pacing, A-V conduction is prolonged by increased heart rate or by deep halothane when the heart rate is held constant. Thus, in addition to the known effects of halothane on pacemaker automaticity, concomitant changes in conduction may contribute to the antiarrhythmic action of this anesthetic.

Radionuclide angiography in the evaluation of ductal shunts in preterm infants.

Radionuclide angiograms were compared with radiographic and physical findings and with echocardiographic left atrial to aortic ratios in 30 neonates clinically suspected of having a persistent ductus arteriosus. In three infants without clinical signs and with normal LA/Ao ratios (10%), radionuclide angiograms provided evidence of a large left-to-right shunt, which was confirmed by the finding of a large ducts arteriosus at surgery. Whereas routine physical, radiographic, and echocardiographic criteria fail to identify some neonates with large PDA's, the present study suggests that radionuclide angiography can be performed in a neonatal intensive care unit setting and may be a valuable addition to currently employed diagnostic techniques.

Measurement of effective renal plasma flow in congestive heart failure.

In the management of patients with congestive heart failure (CHF), it is often desirable to have precise knowledge of overall renal function, including the effective renal plasma flow (ERPF). It has long been recognized that ERPF is diminished in CHF. Since glomerular filtration rate is often decreased to a much lesser extent, other noninvasive procedures such as the measurement of creatinine clearances may not be entirely suitable. ERPF determination by the single plasma sampling (SPS) method affords a rapid, simple, noninvasive, and economical technique that is quite accurate and reproducible. A SPS method has been well-tested in patients following renal transplantation plus a wide variety of nephrological disorders. We have been concerned whether the SPS method would be valid in volume expanded patients. In 28 determinations of ERPF in patients with CHF, and in five patients who did not have CHF, we have found the SPS estimation of ERPF to yield results that are not clinically significantly different from those obtained by the detailed compartmental analysis method. The volumes of 131I-orthoiodohippurate (OIH) distribution were found to be somewhat higher in CHF than in controls, but fractional rate constants were proportionately lower so that intercompartmental flow rates and OIH concentrations were not different from controls. Therefore, the SPS estimation of ERPF is valid in patients with CHF and may be useful in monitoring the renal effects of various hemodynamic and pharmacological interventions.

Conversion from cyclosporine to azathioprine following heart transplantation.

Eleven patients receiving cyclosporine were converted to azathioprine immunosuppression because of persistent creatinine elevation greater than 2 mg/dl 6 months or more following heart transplantation. During conversion, the maintenance steroid dose was doubled for 3 months then tapered to the preconversion dose. Pretransplant renal function in these converted patients was similar to that in a group of azathioprine patients and a group of nonconverted cyclosporine patients. One year following transplant, the nonconverted group had stable but impaired renal function (mean creatinine, 1.45 +/- 0.06 mg/dl; effective renal plasma flow, 407 +/- 39 ml/min; glomerular filtration rate, 68 +/- 8.8 ml/min). The converted patients had evidence of progressive renal dysfunction (mean creatinine, 2.65 +/- 0.19 mg/dl; effective renal plasma flow, 193 +/- 16 ml/min; glomerular filtration rate, 29 +/- 5.1 ml/min). Following conversion, renal function improved toward normal in all patients. There were three episodes of rejection that were successfully treated. An important number of infective and noninfective complications occurred following conversion during the period of steroid augmentation. There were two deaths during the follow-up period. Conversion can be undertaken with low risk of rejection, death, or both, but protocols that employ prolonged periods of steroid augmentation are associated with important morbidity.