[Radiation exposure of health personnel and patients in the heart catheterization laboratory in during vascular brachytherapy]. / Untersuchungen zur Strahlenexposition von Beschäftigten und Patienten im Herzkatheterlabor und bei der vaskulären Brachytherapie.

Interventional radiological measures can lead to high radiation exposures for medical staff. In order to determine the radiation exposure to staff and patients, the resulting radiation exposures were directly measured for 52 measures at an cardiac catheterization laboratory with a new dosimetry system DIS (Direct Ion Storage). Beside the measurement of body dose behind the lead apron, measurements of radiation doses were performed in front of the lead apron and at the wrist of the physician. These measurements were taken as an approximation of the radiation exposure of the non-shielded body parts. The patients dose was estimated by placing a dosemeter close to the head of the patient and from the dose-area product. The mean value of body dose from 52 measurements for the physician behind the lead apron was 1.9 microSv per procedure with a range of 0-9 microSv. In front of the lead apron, a mean value of 53.9 microSv (3-233 microSv) per procedure was obtained. The mean value of partial body dose at the physician's wrist was determined to be 163.2 microSv (12-603 microSv) per procedure. It could be shown that measures combined with interventions lead to higher exposures compared with measures without interventions. For the medical technician, the mean value behind the lead apron was 3.9 microSv (0-58 microSv) per procedure. For the patient, a mean value of 800 microSv (119-8642 microSv) was measured close to the head. The mean dose to the skin of the patient at radiation entrance was determined to be 307 mGy (70-1190 mGy). From this data, the radiation dose per year for the physician performing 1000 measures, was determined to be 1.9 mSv/year. This is below the new dose limit of 20 mSv/year. Also the estimations for the dose to the eye lens and the hands of the physician show no conflicts with actual dose limits when obeying all radiation regulations. The results for vascular brachytherapy did not show significantly higher exposures, compared with conventional measures including interventions.

[Digoxin therapy in patients with long-term digitalis therapy. Comparison of the digoxin blood level after oral administration of digoxin and beta-methyldigoxin]. / Digoxin-Therapie bei dauerdigitalisierten Patienten Vergleich der Digoxin-Serumspiegel nach oraler Gabe von Digoxin und beta-Methyldigoxin.

UNLABELLED: The serum digoxin levels of 23 patients were measured by radio immune assay. The patients were divided into 2 groups receiving either 0,5 mg digoxin b.i.d. or 0,25 mg digoxin b.i.d. orally after having been changed from a maintenance dose of 0,2 mg beta-methyl-digoxin b.i.d. The applicated digoxin was the preparation Lenoxin. The question was whether typical or reduced maintenance doses of digoxin in the new preparation reached therapeutic digoxin serum levels in the absence of renal insufficiency. RESULTS: 1. The maintenance dose of 0,2 mg beta-methyl-digoxin produced stable serum digoxin levels within non-toxic range in all patients; 2. the dosage of 0,5 mg digoxin (group 1) induced accumulation to toxic levels (2,14 mg/ml). A change to 0,25 mg digoxin led to therapeutical serum levels; 3. when using the dosage of 0,25 mg digoxin from the onset of the test (group 2) accumulation was avoided and normal serum digoxin levels were observed during the test period.

[Relationship between digoxin-induced cardiac arrhythmias and serum-digoxin levels (author's transl)]. / Zusammenhang digoxinbedingter kardialer Arrhythmien mit dem Serumdigoxinspiegel

The serum-digoxin level was measured by radio-immunoassay (Immutope) on 245 patients in a coronary care unit. Cardiac arrhythmias were assumed to be digoxin-induced if they disappeared after the drug had been stopped. Patients who had received digitoxin or spironolactone were excluded. The results indicated a normal digoxin range of 1.52 +/- 0.2 ng/ml and a toxic one of 2.78 +/- 0.38 ng/ml. First degree A-V block, atrial ectopic beats and ventricular ectopics with variable coupling intervals were frequently associated with serum-digoxin levels of 1.5-2.5 ng/ml, while higher grade A-V block, atrial tachycardia, bigeminy and atrial tachycardia with block were more frequent with higher serum-digoxin levels (greater than 3.0 ng/ml). Atrial arrhythmias were especially frequent with serum levels above 3.0 ng/ml. This suggests different sensitivities of atrial and ventricular myocardium. Atrial arrhythmias thus in general indicate a higher degree of toxicity at high serum levels, while ventricular ectopic beats occur both with high serum levels and also with increased digoxin sensitivity of the ventricles.

[Serum glycoside concentration and digoxin intoxication]. / Serumglykosid-Konzentration und Digoxin-Intoxikation

Serum digoxin levels, estimated by radioimmuno assay, technique, and the pattern of cardiac arrhythmias due to digoxin intoxication seem to be correlated in cases with high serum digoxin levels. The prognostic value of those correlations is demonstrated and discussed. Serial observations of the course of cardiac arrhythmias under the suspicion of digoxin intoxication together with blood level measurements allow to introduce more objective criteria in clinical management of poor risk patients receiving digoxin.

Complications of permanent transvenous cardiac pacing.

Clinical experience with permanent transvenous pacing during a 6 year period at Hannover Medical School is presented. A total of 1,376 pacemaker operations were performed in 799 patients, with a mortality rate of 1.1 per cent. The most common complications were premature battery failure, dislocation of endocardial electrodes, infections of the generator and/or electrodes, and skin ulcerations. In our cumulative follow-up period of 1,225 years, a complication necessitating a reoperation is to be expected after an average function-time of 31 months. Including normal battery exhaustion in this calculation will make reoperation necessary every 21.9 months.