Biomedical subjects

H Gloor

Publications and source records attributed to H Gloor.

15 recordsLinked to original sources

PubMed1991

Relative preservation of the responsiveness to endothelin-1 during reperfusion following renal ischemia in the rat.

Reperfusion after renal ischemia is characterized by a preglomerular vasoconstriction. As endothelin-1 (ET-1) is a potent preglomerular vasoconstrictor, we designed a study to investigate the role of ET-1 in postischemic renal vasoconstriction. Renal ischemia was induced by 45 min of left renal artery clamping in anesthetized rats. After ischemia, renal blood flow was restored to only 61 +/- 4% of its preischemic value. The sensitivity to exogenous ET-1 after renal ischemia was decreased, but much less than the sensitivity to angiotensin II, which almost lost its vasoconstrictor effect, and to norepinephrine, which became a vasodilator. In addition, the binding affinity of [125I]ET-1 in the kidney increased significantly after renal ischemia, despite no change in the density of binding sites. These findings may be in favor of a role of endogenous ET-1 in postischemic renal vasoconstriction.

Angiotensin II↗

PubMed1990

Clinical experience with a new software-based antitachycardia pacemaker for recurrent supraventricular and ventricular tachycardias.

The Intermedics Intertach 262-12 tachycardia reversion pulse generator was implanted in 14 patients (six male, eight female, mean age at implantation 45 +/- 16 years) with recurrent symptomatic tachycardias. Six patients had atrioventricular (AV) nodal reentrant tachycardia, three patients had orthodromic tachycardia with Wolff-Parkinson-White syndrome, two had circus movement tachycardia via a concealed bypass tract, two had ventricular tachycardia, one patient had atrial flutter. Mean duration of symptoms before implantation was 8 +/- 4 years and mean number of antiarrhythmic drug trials was 3.5 +/- 1. The primary tachycardia response made consisted of autodecremental pacing in one patient, burst pacing in two patients, and adaptive scanning of the initial delay or burst cycle length in eleven patients. The secondary tachycardia response mode consisted of autodecremental pacing in four patients, burst pacing in three patients and burst scanning in four patients. Tachycardia response was automatic in all but one patient with ventricular tachycardia. During a follow-up period of 30.5 +/- 10.6 months, one patient with ventricular tachycardia died from a nonarrhythmic cause. Reinterventions were necessary due to electrode fracture in one patient and due to pacemaker software defect in another one. Two patients underwent surgical cure of their arrhythmia: one patient with atrial flutter and one patient with AV nodal reentry tachycardia, 24 months and 11 months postpacemaker implantation, respectively. Four patients required digitalis to prevent pacing induced atrial fibrillation. Other proarrhythmic effects were not encountered. The pacemaker proved to be a versatile system with reliable tachycardia detection and termination functions. It provided a valuable adjunctive therapy in these selected patients.

Adult↗

PubMed1990

Clinical experience with the Intertach 262-12 pulse generator in patients with recurrent supraventricular and ventricular tachycardia.

An antitachycardia pulse generator, the Intermedics Intertach 262-12 was implanted in 16 patients (14 patients with supraventricular tachycardia of various origins and two patients with recurrent ventricular tachycardia), who were not responsive to various antiarrhythmic drug regimens. The follow-up was from 6-49 months (mean 30.9 +/- 13.8). Five patients had a follow-up of over 3 years. The device was used in all patients. One patient with ventricular tachycardia died from a nonarrhythmic cause. Loss of responsiveness to burst pacing was observed in 1/14 patients with supraventricular tachycardia and nontolerance of antitachycardia pacing in one patient. Overall clinical success of pacing was observed in 13/16 patients = 81%. The pacemaker proved to be a versatile system with reliable tachycardia detection and termination functions.

Adult↗

PubMed1988

[Prolonged course in patients with symptomatic ventricular tachycardia].

In a retrospective study we analyzed the long-term course in 77 patients (71 males and 6 females) with symptomatic ventricular tachycardias. Initially all patients had undergone an electrophysiological examination. 56/77 patients received drug therapy and 19/77 underwent surgery (implantation of an automatic defibrillator in 2 patients). Two patients received no therapy. After an observation period of 30 (5-81) months, 60% of the patients who had received drug therapy and 77% who had undergone surgery were free of tachycardia. 16/56 (29%) of the patients under drug management and 6/19 (32%) of the surgically treated had died in the meantime. In the whole group the mortality rate was 9.6 times higher than in an age and sex matched control group. In younger subjects (16-50 years) the mortality rate was 4 times greater than in those aged 51-81 years. The highest mortality was observed in the first year. The most important prognostic parameter was the left ventricular ejection fraction, which was significantly higher in survivors. We conclude that ventricular arrhythmias can be effectively controlled, and quality of life enhanced, with drug therapy or surgery.

Adolescent↗

PubMed1985

[Effect of heart rate on the refractory period of the accessory atrioventricular pathway in Wolff-Parkinson-White syndrome].

Electrophysiologic investigations have been performed in 13 patients with symptomatic WPW syndrome. The effective refractory periods of the right atrium (AERP), the antegrade effective refractory periods of the accessory pathway (AP-ERP) during sinus rhythm and at different cycle length, the shortest RR-intervals with preexcitation during atrial fibrillation (RR-AF) and the appearance of block in the AP during incremental atrial pacing have been measured. The data collected during sinus rythm (SR) and at different pacing rates were analyzed and compared. During SR (cycle length 851 +/- 157 ms) AERP measured 263 +/- 56 ms and AP-ERP 309 +/- 55 ms. At a cycle length of 450-550 ms, AERP measured 221 +/- 36 ms and AP-ERP 250 +/- 35 ms, and at a cycle length of 400-450 ms AERP was 213 +/- 35 ms and AP-ERP 230 +/- 42 ms. The mean RR-AF was 253 +/- 35 ms. A significant correlation was found between AERP and AP-RP at a cycle length of 400-450 ms (r = 0.92), but not between AP-ERP and RR-AF at any cycle length. Block in the AP occurred at a mean pacing cycle length of 280 +/- 42 ms. The electrophysiologic measurements of patients with syncope did not differ from patients without syncope in our group. The data show that in patients with a long AP-ERP (greater than 290 ms) during SR an increase of the heart rate leads to a significant shortening of the AP-ERP. No relevant correlation was found between AP-ERP and mean RR-AF. Patients with AP-ERP shorter than RR-AF appear to be a high-risk subgroup for ventricular fibrillation during AF.

Adolescent↗

PubMed1982

Genetic effects in the mouse of formaldehyde in combination with adenosine and hydrogen peroxide.

Male mice of the Q strain were injected (i.p.) with a synthetic methylene dinucleotide (Ado-CH2-Ado) and with a mixture of formaldehyde and hydrogen peroxide. Neither injection induced any chromosome lesions in spermatogonia. In the dominant lethal mutation test, the mixture of formaldehyde and hydrogen peroxide had an effect throughout spermatogenesis, but only the rate of pre-implantation losses was increased. Injection of Ado-CH2-Ado increased both pre-and post-implantation deaths at the 1st week but only the frequency of pre-implantation losses at the 6th week.

Adenosine↗

PubMed1969