Radionuclide bone scans and skeletal radiographs were obtained before and during combination chemotherapy or initial hormonal treatment in 46 patients with disseminated adenocarcinoma of the prostate. The purpose of the study was to determine the usefulness of these two modalities in evaluating tumor response to therapy. Prior to treatment, bone scans were positive in 44 patients (96%). In all but one patient either bone radiographs or bone marrow biopsy revealed evidence of osseous metastases. In 22 patients partial response to therapy was documented by a variety of other staging tests. Eleven of these patients showed concurrent or later improvement on bone scans; one showed improvement on a radiograph. "Flare phenomena" were observed relatively frequently since 23% of the scans and 50% of the radiographs showed worsening at the time of response. Bone scans revealed worsening in 79% of 33 patients with disease progression of extraosseous tumor; radiographs were equally sensitive (82% worsening). It is concluded that bone scans in particular are useful for monitoring tumor status in systemically treated patients with prostate cancer. However, because of the lack of sensitivity for response and paradoxical worsening with tumor regression in some patients, scans are not accurate enough to be employed as the sole test in following these patients.
SUMMARY The effects of encainide on ventricular arrhythmia and left ventricular function were studied in 21 patients with chronic, high-grade ventricular arrhythmia using a prospective, 3-month, placebo-controlled, single-blind trial design.Encainide caused a 96% decrease in the average hourly frequency of ventricular premature complexes (VPCs) and comparable reductions in salvos of nonsustained ventricular tachycardia (VT) and episodes of sustained VT. Intracardiac electrophysiologic testing showed prolonged intraatrial and intraventricular conduction times and increased atrial, atrioventricular nodal, and ventricular refractory periods with both i.v. and oral encainide without His-Purkinje block, despite marked prolongation of HV and QRS intervals. Induced repetitive ventricular beating after ventricular extrastimuli in 15 patients showed persistent repetitive ventricular beating with chronic oral encainide in seven patients, four of whom had sustained VT within 2 months of treatment on encainide. Encainide did not reduce exercise capacity or left ventricular ejection fraction at rest or during supine exercise. Minor adverse effects of encainide in 11 of 21 patients included dose-related visual disturbances, dizziness and sinus pauses (< 3 seconds). Major adverse effects included the new appearance of sustained VT in three of 20 patients (15%).Oral encainide effectively reduces the frequency and grade of VPCs, prolongs intracardiac conduction times, and does not impair left ventricular performance. However, it is associated with frequent minor side effects and uncommon but potentially severe major side effects (sustained VT), both of which apparently have a direct relationship to the size of the dose. 1134 frequency ventricular arrhythmia were studied. In addition, the study design included quantification of ventricular arrhythmia during multiple 24-hour ambulatory ECG recordings obtained during alternating placebo and encainide treatment phases. The effects of encainide on exercise-related ventricular arrhythmia were also evaluated during treadmill testing. Exercise duration and myocardial performance were studied off and on encainide using treadmill exercise testing and radionuclide cineangiography at rest and during exercise. The electrophysiologic effects of acute i.v. and chronic oral encainide, including the response to provocative extrastimulus techniques, were determined at cardiac catheterization.", 12
MethodsPatient Characteristics (table 1) All patients were older than 21 years of age and had a history of frequent ventricular arrhythmias (minimum mean VPC frequency . 60 beats/hour for at least 48 hours) for more than 3 months, without known reversible cause. No other antiarrhythmic agents were allowed during the trial; however, digitalis, diuretics and potassium supplements for patients with congestive heart failure and A-blocking agents for patients with angina pectoris were continued without modification (table 1). Each patient gave informed consent before the study. The protocol was approved by t...
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