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Biomedical subjects

R Kolvenbach

Publications and source records attributed to R Kolvenbach.

10 recordsLinked to original sources
PubMed1992

Antioxidant depletion in aortic crossclamping ischemia: increase of the plasma alpha-tocopheryl quinone/alpha-tocopherol ratio.

To assess whether oxidative stress contributes to the ischemia/reperfusion injury of aortic surgery, the contents of alpha-tocopherol, alpha-tocopheryl quinone, ascorbate, lipid-derived malondialdehyde, protein thiols, cholesterol, and lactate were analyzed in plasma samples from 24 patients subjected to aortic crossclamping. alpha-Tocopherol, ascorbate, and protein thiols decreased during ischemia, whereas alpha-tocopheryl quinone increased in all but two cases, doubling on average in proportion to alpha-tocopherol. Upon reperfusion alpha-tocopherol, ascorbate, and protein thiols remained low, whereas alpha-tocopheryl quinone returned to the preischemic level. Lipid-derived malondialdehyde (a measure of lipid hydroperoxides) increased significantly only during reperfusion. The results suggest that oxidative stress occurs simultaneously with ischemia/reperfusion during aortic surgery, and that measurement of the tocopheryl quinone/tocopherol ratio may shed new light on the underlying pathological events.

Aged↗
PubMed1990

["Inflammatory aneurysm" of the aorta. Diagnosis, therapy, results].

From 1970 to 1987 among 964 patients with aortic aneurysms 52 (5.4%) underwent aortic graft replacement for inflammatory aortic aneurysm. 79.2% were symptomatic, 18.9% ruptured at the time of admission. CT-scan is of main diagnostic value. The perioperative mortality rate was 15.1%. At follow-up (28 months mean) 35 of 38 living patients (92.7%) were examined clinically, by sonography and in most cases by CT-scan. The late complication rate was 20% (n = 7, atrophic kidney 3, anastomotic aneurysms 4). In contrast to abdominal aortic aneurysms inflammatory aneurysms present an elevated morbidity and mortality rate which has to be reduced by exact preoperative diagnosis and modified surgical technique.

Aged↗
PubMed1979

[The clinical relevance of intraoperative electrophysiologic mapping (author's transl)].

Electrophysiological intraoperative mapping is described as a technique for identification of the specialized AV conduction system during open heart surgery; furthermore it is suitable for delineating the morphological origin of ventricular tachycardias which requre surgical therapy. The mapping technique is described with respect to its methodical aspects and illustrated by means of congenital and acquired heart disease.

Bundle of His↗
PubMed1979

Intraoperative electrophysiologic mapping during cardiac surgery.

Intraoperative mapping is a method to document the surgical anatomy of cardiac tissues with electrophysiologic importance cartographically at time of surgery. The presented communication gives a survey of the present status of the technique of electrophysiologic mapping and its essential clinical applications. Special attention in this regard is directed to the intraoperative identification of the specialized AV conduction system in congenital cardiac malformations with unpredictable location of His bundle, to the detection of accessory AV bundles in patients with the Wolff-Parkinson-White syndrome and to the intraoperative morphological study of ventricular reentry tachycardias. Suitable technical equipment for "clinical" intraoperative electrophysiologic mapping is described in detail.

Cardiac Surgical Procedures↗
PubMed1979

[Electrophysiological mapping during open-heart surgery (author's transl)].

Intraoperative electrophysiological mapping provides a method to identify the specialized atrioventricular conduction system and to localize the morphological origin of different tachycardiac rhythm disorders at time of surgery. The basic technical aspects and methodical implications are presented with respect to its clinical applications.

Atrioventricular Node↗