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K Wegscheider

Publications and source records attributed to K Wegscheider.

36 records · Page 2Linked to original sources
PubMed1988

Functional versus structural changes of forearm vascular resistance in hypertension.

Structural changes in resistance vessels have been considered an important factor in triggering and maintaining chronic hypertension in humans and in experimental animals. To determine whether the increased forearm vascular resistance observed following vasodilator maneuvers in hypertensive patients is predominantly due to structural or to functional changes, we examined the influence of different vasodilator stimuli on forearm blood flow and blood pressure in 22 male patients with established essential hypertension and in 22 age-matched normotensive men (age range, 28-52 years). Blood pressure was measured directly, and blood flow was measured by venous occlusion plethysmography. The maneuvers applied were 1) arterial occlusion combined with handgrip exercise and local heating, 2) intra-arterial infusion of the calcium entry blocker nifedipine, 3) intra-arterial infusion of the nonspecific vasodilator sodium nitroprusside, 4) arterial occlusion initiated after intra-arterial infusion of nifedipine. Vascular resistance during vasodilation induced by arterial occlusion or infusion of nifedipine or sodium nitroprusside remained significantly higher in the hypertensive than in the normotensive subjects. However, the maximal vasodilation achieved by the combination of arterial occlusion and nifedipine resulted in a similar resistance in both groups (1.6 +/- 0.2 in the hypertensive vs 1.4 +/- 0.2 mm Hg/ml/min/100 ml tissue in the normotensive subjects. These data suggest that there is an important functional component of the elevated resistance in patients with essential hypertension.

Adult↗
PubMed1986

[Comparative study of the anti-arrhythmia effect of flecainide acetate and prajmalium bitartrate in patients with tachycardiac ventricular rhythm disorders].

In an open randomized therapeutic study, 20 patients known to have frequent ventricular premature beats (VPB) and/or ventricular pairs (VP) were treated with both 2 X 200 mg flecainide (F) and 4 X 20 mg prajmalium-bitartrate (P) for 3 months each. There was a drug-free interval of one week between the two therapy phases. 24-hour long-term ECG-registrations were carried out before the start of the therapy phases as well as 1 week, 1 month, 2 months and 3 months after the initiation of antiarrhythmic therapy. After one week, the group as a whole evidenced a VPB reduction of 94% under F and only 57% under P (p less than or equal to 0.05). The percentage of individual patients in whom there was a statistically significant VPB reduction was also higher under F than under P (65% vs. 40%). In the group as a whole, there was a VP reduction of 99% under F and 88% under P (p less than or equal to 0.05) after one week. Of the 13 individuals with frequent VP (over 16 VP/24 h), a significant reduction was seen in 77% under F and only 38% under P. The difference between the two antiarrhythmic agents registered after one week was also observed in the further course of therapy but could no longer be statistically confirmed for the ventricular pairs. An aggravation of ventricular arrhythmias was observed in 2 patients under F and in 3 under P.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Idiopathic ventricular tachyarrhythmia. Spontaneous variability and effect of various antiarrhythmic agents].

20 patients with idiopathic complex ventricular arrhythmias received propafenone 450 mg/d, disopyramide 600 mg/d and metoprolol 100 mg/d. Before commencement of the 3-week treatment period the 95% normal range for spontaneous changes in ventricular extrasystoles (VES), as couplets and runs, were determined from three 24 h-ECG recordings in each patient under drug-free conditions. A drug effect was assumed when the rate of VES/24 h for the control period decreased by greater than or equal to 83.5% or increased by greater than or equal to 505% in the test period. The frequency dependent normal range for couplets varied between a decrease from 100% to 92% (greater than or equal to 16 to greater than or equal to 44/d) and an increase from 650% to 1000% (greater than or equal to 3 to greater than or equal to 38/d) and for runs between a decrease from 100% to 85% (greater than or equal to 6 to 32/d) and an increase from 600% to 1000% (greater than or equal to 1 to 14/d). A decrease in all rhythm disturbances under the action of the 3 drugs could be shown for the whole group (P less than 0.01). On the basis of the calculated normal range, ventricular extrasystoles in the patients decreased significantly by 26-37%, couplets by 13-33% and runs by 0-55% depending to the drug. A drug dependent arrhythmogenic effect occurred in 4 patients. A preference for one or other of the drugs could not be established statistically.

Adult↗
PubMed1985

Follow-up of prostaglandin plasma levels after acute myocardial infarction.

Prostaglandin plasma levels are elevated in patients with transient myocardial ischemia. We measured 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane (B2(TXB2) in venous blood of 32 patients with myocardial infarction on the first, third, and seventh days. TXB2 and 6-keto-PGF1 alpha levels in these patients (up to 117 +/- 237 pg/ml and 96 +/- 105 pg/ml mean +/- SD, respectively) differed significantly from levels in normal control subjects (10 +/- 12 pg/ml and 4 +/- 7 pg/ml mean +/- SD, respectively) (p less than 0.01). Prostaglandin values remained elevated from day 1 through day 7. In most patients, 6-keto-PGF1 alpha levels prevailed over those of TXB2. In a subgroup suffering from cardiac arrhythmias, the ratio of 6-keto-PGF1 alpha/TXB2 was inverse. It is concluded that prostaglandin generation is increased for at least 7 days after myocardial infarction. A disturbed ratio of 6-keto-PGF1 alpha/TXB2 in favor of the latter might be associated with cardiac arrhythmias in myocardial infarction.

6-Ketoprostaglandin F1 alpha↗
PubMed1985

Prophylaxis of constipation by wheat bran: a randomized study in hospitalized patients.

To evaluate the efficacy of wheat bran in preventing constipation, 200 hospitalized patients were randomly allocated to groups receiving either a dietary supplement of 40 g bran daily or no dietary supplement at all. A quarter of the bran group patients refused to take their bran from the very beginning (refusers), one third stopped bran consumption during the study (dropouts), and only 42% of the patients continued on bran until discharge or death (participants). Independent of a previous history of constipation, neither the hospital incidence of constipation nor the average percentage of days on laxatives was significantly different between the bran group and the control group. Only the dropouts were significantly more constipated than the control patients, whereas no such difference could be demonstrated in the refusers or participants. It is concluded that the administration of bran as a prophylactic laxative confers no benefit in patients hospitalized for a relatively short time.

Aged↗
PubMed1984

[Standardized psychological stress test for the provocation of tachycardial ventricular arrhythmias. Comparison with long-term ECG and stress ECG].

The effect of a standardized psychological stress test on frequency and severity of ventricular extrasystoles was compared in 42 patients with the results of 24-hour ECG monitoring and of an exercise ECG test. Frequent ventricular extrasystoles (greater than 1/min) occurred in the 24-hour-ECG in 22, in the psychological stress test in 24 and on physical exercise in 22 patients. 24-hour monitoring gave the only positive finding in ten, the psychological stress test in six, the exercise test in four. Complex arrhythmias (coupled or runs of ventricular extrasystoles) occurred in the 24-hour ECG in 30, with the psychological stress test in 16 and the exercise test in 12 patients. The 24-hour ECG was alone positive in 16, the psychological test in two, the exercise test in one. Thus in an individual patient the psychological stress test may provoke additional arrhythmias which are not recorded in either the 24-hour ECG or after exercise. The findings point to an independent significance of the psychological stress test in the diagnosis of simple and complex ventricular arrhythmias.

Adult↗
PubMed1984

[A new method for the evaluation of the success of anti-arrhythmic drug therapy and a paradoxical drug-induced arrhythmogenic effect in individual patients].

The aim of this study was to develop standards to define both antiarrhythmic drug efficacy and a drug-induced arrhytmogenic effect. In 45 patients with frequent and complex ventricular tachyarrhythmias 3 continuous 24-hour Holter recordings were performed. The spontaneous variability of ventricular premature beats and ventricular pairs was calculated using a new statistical method (transformation model). If two 24-hour Holter monitoring periods, one period before and the other with antiarrhythmic therapy, are compared, at least 75% reduction of ventricular premature beats and 90% reduction of ventricular pairs is necessary to be reasonably certain that one is measuring a drug response rather than spontaneous arrhythmia reduction (p less than or equal to 0.05). On the other hand, drug-induced aggravation can be assumed if ventricular premature beats and ventricular pairs have increased by more than 144% and 227%, respectively (p less than or equal to 0.05).

Anti-Arrhythmia Agents↗
PubMed1984

[Normal ranges of the regional movement of the left ventricular wall in 2-dimensional echocardiography].

Two-dimensional echocardiographic (2D-Echo) studies were performed in 51 healthy subjects to set up normal ranges of regional left ventricular (LV) wall motion for three different standard planes: the short axis (SA), recorded at a level between the mitral valve and the papillary muscles, the apical two-chamber view (2 CV) and the apical four-chamber view (4 CV). Wall motion analysis was performed using a fixed (Fix) as well as a floating reference system (Float). For regional wall motion, calculated by segmental area shortening, tolerance limits were estimated by using two well established statistical methods. The lowest coefficient of variation (V) was found for the SA (VFix = 0.18; VFloat = 0.11). The apical planes showed higher variations (2 CV: VFix = 0.20, VFloat = 0.20; 4 CV: VFix = 0.26, VFloat = 0.19). Defining the normal LV contraction ranges, a comparison of the reference systems showed advantages of the floating procedures, mainly in the SA and in the 4 CV. The obtained normal contraction ranges can be used for the evaluation of regional LV contraction abnormalities after acute myocardial infarction (AMI) if the 2D-Echo images are of excellent quality. We suggest an "index of dyssynergy" as a measure of wall motion abnormality.

Adult↗
PubMed1984

Prostaglandin production in patients with pulmonary embolism.

Release of prostaglandins (PG's) after experimental pulmonary embolism has been reported. Therefore, prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2 alpha), thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were determined in venous plasma of 21 patients with acute pulmonary embolism. Venous plasma levels were followed up for one week after admission. Arterial and mixed-venous PG levels were additionally determined in 6 patients with acute pulmonary embolism prior to pulmonary angiography. Venous levels were substantially elevated (PGE2 16-1300, PGF2 alpha 48-592, TXB2 1-247, 6-ketoPGF1 alpha 1-248 pg/ml), differing significantly from normal controls (p less than 0.001). PG's remained elevated throughout the 7-day postadmission study period. No significant arterial-venous PG differences were detected, though 6-keto-PGF1 alpha and TXB2 levels were somewhat higher in arterial blood. There was no correlation between clinical data (blood pressure, mean pulmonary artery pressure, etc.) and PG levels. These data suggest that elevated prostaglandin levels are probably not, or only in part, responsible for the cardiopulmonary changes that occur in patients with acute pulmonary embolism.

6-Ketoprostaglandin F1 alpha↗
PubMed1983

Avoidance of perinatal transmission of hepatitis B virus: is passive immunisation always necessary?

Screening of 8918 pregnant women revealed that 107 (1.2%) were HBsAg-positive. 92 of them (50 of German and 42 of predominantly Asian origin) have already delivered and were followed up for 12 months together with their infants. 14 infants of HBeAg-positive (or anti-HBe-negative) carrier mothers received a single dose of hepatitis B immunoglobulin (HBIG) immediately after birth, while 60 infants of anti-HBe-positive mothers were not immunised. 57 of the 60 "unprotected" children remained seronegative for HBsAg and HBeAg. 3 children showed HBs-antigenaemia immediately after birth; 2 of these lost HBsAg and developed anti-HBs after 6 and 9 months. The third lost HBsAg after 4 months without an antibody response developing. This suggests that the HBsAg particle only was transmitted rather than the whole virus. 12 of the 14 infants born to HBeAg-positive, or anti-HBe-negative carrier mothers were protected with one single high dose of HBIG. 2 had HBs-antigenaemia, 1 had HBeAg as well. These data show that in a West European population the risk of perinatally acquired HBV infection in the infants of anti-HBe-positive carrier mothers is small, and that passive immunisation of this group is not necessarily indicated.

Asia↗
PubMed1983

Intravenous short-term infusion of streptokinase in acute myocardial infarction.

Short-term i.v. infusion of streptokinase was performed in 93 patients within 6 hours after the onset of acute myocardial infarction. Twenty-six patients underwent angiography in the acute phase (group A) and 52 underwent angiography in the fourth week only (group B); 15 patients had no angiography. Seven patients died during the hospital stay and six suffered nonfatal reinfarctions. There were no bleeding complications. In 11 of 21 group A patients, occluded coronary arteries were opened within 1 hour after the streptokinase infusion was started. In 84% of groups A and B, the infarct-related coronary artery was patent in the fourth week. In 75% of the patent arteries, the residual luminal diameter stenosis was less than 70%. According to serial serum CK-MB curves, recanalization was achieved mostly within 1-2 hours. Myocardial salvage was indicated by improvement in local contraction disorders in the recanalized group A patients and by the significant relationship between infarct size and time from symptom onset to treatment in group B. These data suggest that a high-dose, short-term, i.v. infusion of streptokinase is a safe and efficient method of restoring coronary blood flow. Expeditious initiation of i.v. streptokinase infusion is a critical determinant for early recanalization and salvage of myocardium. Patients with thrombotically subtotal occlusion probably receive the most benefit. Evaluation of the true impact on survival and myocardial function will require controlled clinical trials.

Adult↗
PubMed1982

[Demonstration of complex ventricular tachy-arrhythmias by long-term ECG monitoring: relationship to duration of monitoring].

Continuous long-term ECG monitoring over three 24-hour periods was undertaken in 42 patients with complex ventricular tachy-arrhythmias. The arrhythmias were divided by degree of severity. The lowest degree was assigned to frequent ventricular extrasystoles (more than 20 per hour). The next degree was assigned to ventricular bigeminal rhythm, while runs of extrasystoles were assigned the highest degree. In 30 patients the highest arrhythmia level was reached within the first 24-hours, in nine after a further 24 hours, in three during the third 24-hour period. Comparing the three periods of registration there were differences between the various arrhythmias, not of kind but of frequency of the arrhythmia. Simple VES and the complex forms differed in their occurrence: although of 33 patients with frequent VES (more than 20/h) 30 also had runs of VES, in six patients with runs of VES the frequency of extrasystoles was low (less than 20/h). In 70% of cases 24-hour monitoring was sufficient to record the highest level of ventricular tachy-arrhythmia. If, however, no severe arrhythmias have been recorded during this period, increasing the duration of monitoring to 48-hours can be useful. A third period or more is of little further value.

Adult↗
PubMed1982

[Relations between ventricular extrasystole, time of day and heart rate].

42 patients with complex ventricular arrhythmias were subjected to continuous long-term ECGs for three 24-hour periods. In 21 patients, the occurrence and frequency of simple ventricular premature beats (VPB) did not depend on whether it was day or night. The other 21 patients showed a regular reproducible day-and-night rhythm during all three registration periods. 14 (33%) of them had the highest VPB-frequency during day and 7 (17%) at night.--16 patients showed paired VPB. Again, only 50% (8 patients) showed a regular reproducible day-and-night rhythm during all three registration periods. 6 of them had the highest frequency of paired VPB during day and 2 at night. 23 patients showed a clearly recognizable relationship between VPB-frequency and heart rate during all three periods. In 18, the VPB-frequency ran parallel to the heart rate, but in 5 patients the VPB-frequency ran contrary to the heart rate. In 16 patients, the VPB-frequency showed a constant relationship to both heart rate and time of day, 5 patients only evidenced a relationship to time of day and 7 only to heart rate. The distinct dependence of VPB-frequency upon heart rate and/or time of day in numerous patients could be of differential therapeutic significance.

Adult↗
PubMed1982

[Systemic thrombolysis with short-term streptokinase infusion in acute myocardial infarct].

Within 6 hours after the onset of acute myocardial infarction, 93 patients received a brief high-dose intravenous infusion of streptokinase, 49 patients received 500,000 IU within 30 min and 44 patients received 1,500,000 IU within 60 min. 26 patients had angiography in the acute phase, after 24 hours, and in the 4th week; 52 patients had angiography in the 4th week only; and 15 had no angiography. 7 patients died in hospital and 6 suffered a nonfatal reinfarction. There were no complications with bleeding. In 52% of cases, reopening of an occluded infarct vessel was achieved within 1 hour of the beginning of treatment. During the 4th week after infarction a patent infarct vessel was found in 84%, and 58% had a residual stenosis less than 70%. In contrast, in a control group that received no streptokinase treatment, 25% had a patent infarct vessel and 4% had a residual stenosis less than 70%. Indicative for salvage of ischemic myocardium are a significant improvement in local contraction disorders between the acute phase and the 4th week and a significant correlation between infarct size in the 4th week and beginning of treatment after onset of symptoms. 1. It may be concluded that: brief intravenous infusion of streptokinase results in restoration of blood flow in an infarcted coronary artery in a high percentage of cases; the shorter thrombus-lysis time with intracoronary streptokinase infusion could be made up for by the earlier initiation of intravenous streptokinase treatment; and a conclusive randomized trial is needed to ascertain the true impact of a brief high-dose intravenous infusion of streptokinase on mortality and morbidity following acute myocardial infarction.

Adult↗