Biomedical subjects

H Schmidinger

Publications and source records attributed to H Schmidinger.

46 records · Page 3Linked to original sources

PubMed1988

Subsidiary pacemaker function in complete heart block after His-bundle ablation.

To investigate the electrophysiological properties of ventricular impulse formation after His-bundle ablation in 11 patients, incremental ventricular overdrive stimulation studies were performed. The studies, which were spread over a follow-up period of up to 601 days, were carried out invasively with temporary leads as well as noninvasively with the implanted pacemakers and chest wall inhibition. The overdrive pacing rate was increased in steps of 10 beats/min, and the pacing duration was 2 minutes at each level. Ten out of 11 patients had a reliable ventricular escape rhythm; in the remaining patient, consistently no subsidiary pacemaker function was observed up to 10 seconds. In 83% of the studies, incremental ventricular overdrive stimulation caused progressive suppression of ventricular impulse formation with exponential increase in ventricular recovery time and progressive postrecovery subsidiary pacemaker depression. In the remaining 17%, ventricular recovery time showed a heterogeneous response to overdrive stimulation--as possible cause alterations in the sympathetic tone and limitations attributable to the method used are discussed. The results of this study demonstrate a rate-dependent overdrive suppression of subsidiary ventricular pacemaker tissue. This can be of clinical importance in patients with complete heart block and rate-adaptive pacemakers because sudden pacemaker failure or temporary pacemaker inhibition at high stimulation rates may cause Stokes-Adams attacks not reproducible at lower pacing rates.

Aged↗

PubMed1987

Potential life-threatening cardiac arrhythmias associated with a conventional hypocaloric diet.

Nine obese children (mean age 12.7 years, mean overweight 74.2%) were treated for 3 weeks with a very low calorie diet containing high quality protein. Eight patients (patients A) received a commercially available diet (240 kcal/1004 kJ/day) and 1 patient (patient B) a homemade dietary regimen (500 kcal/2100 kJ/day). Both preparations were supplemented with micronutrients; however, the daily intake of minerals was significantly less in patient B. All patients were monitored for the appearance of cardiac arrhythmias by frequent 24-hour Holter recordings. In patients A the mean loss of body weight was 9.4 +/- 2.4 kg, patient B lost 8.7 kg. The mean daily nitrogen balance was negative (patients A: 10.2 g/day, patient B: 6.8 g/day). Frequent blood chemistry evaluations were unremarkable. On the 14th day of treatment patient B developed arrhythmias (ventricular couplets, non-sustained ventricular tachycardias); in patients A no ventricular dysrhythmias were observed. Our data suggest that very low calorie diets containing protein of high biologic value can be associated with potentially dangerous arrhythmias.

Adolescent↗

PubMed1987

Sudden death during ambulatory Holter monitoring.

Four cases of sudden cardiac death during ambulatory Holter monitoring are described. All had coronary arterial disease. Two patients were on antiarrhythmic drug therapy and both had a prolonged QTc-interval on their resting electrocardiogram. The predominant rhythm was sinus rhythm in all. In one patient, severe bradycardia terminated in asystole. In the remaining 3 patients, ventricular flutter (which was initiated in 2 instances by a short run of polymorphous ventricular tachycardia) degenerated into ventricular fibrillation. The lethal event was triggered once by an early cycle ventricular premature beat and twice by late cycle ventricular premature beats. There was no specific pattern of warning arrhythmias preceding sudden cardiac death. Signs of ischemia/sympathetic overactivity preceding sudden cardiac death were found in 3 patients. Autopsy studies were performed in 2 patients and revealed acute ischemic myocardial damage.

Aged↗

PubMed1987

Dysrhythmias following the Mustard and Senning operation for transposition of the great arteries.

The prevalence and nature of late dysrhythmias following operative repair of transposition of the great arteries were evaluated in 32 children using pre- and postoperative standard electrocardiograms and postoperative Holter monitoring. The Mustard procedure was performed in 17 patients, the Senning procedure in 15 patients. The mean age at operation was 40 +/- 35 months in the Mustard and 9 +/- 6 months in the Senning group. The mean interval between operation and Holter monitoring 7 +/- 2 years in the Mustard and 1.6 +/- 1 years in the Senning group. All patients had sinus rhythm preoperatively. Following operation, the incidence of sinus rhythm increased from 59% in the Mustard and 87% in the Senning group in the first postoperative week to 76% in the Mustard and 100% in the Senning group at the end of follow-up (mean 4.6 +/- 3.5 years). Holter monitoring revealed dysrhythmias or conduction abnormalities in 12 patients (9 Mustard, 3 Senning). A permanent pacemaker had to be inserted in 2 Mustard patients because of complete atrioventricular block and sinus bradycardia with sinus arrest, respectively. Results indicate a prevalence of late postoperative dysrhythmias of 20% in the Senning and of 59% in the Mustard group (p less than 0.05). However, the significantly longer mean follow-up period of the Mustard group precludes a direct comparison between the 2 types of repair.

Arrhythmias, Cardiac↗

PubMed1986

[A new method for the treatment of supraventricular rhythm disorders].

Initial experience of His-bundle ablation is presented in 12 patients with intractable supraventricular arrhythmias which were not amenable to treatment with conventional drugs. In 8 patients His-bundle ablation resulted in total AV-block and in 2 patients significant improvement without total AV-block was achieved. During long-term follow-up (mean 5.3 months) tachycardia recurred in 1 patient with total AV-block resulting in an overall success rate of 75%. A permanent pacemaker was implanted in 10 patients. 1 patient developed deep leg vein thrombosis as a direct result of this procedure and in 2 patients there were complications due to pacemaker implantation. His-bundle ablation appears to be a promising tool in the management of intractable supraventricular tachycardia.

Aged↗

PubMed1971