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F C Schoebel

Publications and source records attributed to F C Schoebel.

50 records · Page 3Linked to original sources
PubMed1997

[Chronic intermittent urokinase therapy: anti-ischemic and hemodynamic effects].

Long-term intermittent urokinase therapy has been developed for patients with severe coronary artery disease and refractory angina pectoris. This therapeutic approach is predominantly effective at the microcirculatory level based on a combination of rheologic and fibrinolytic effects; furthermore, plaque regression seems to be a possible mechanism. Patients with refractory angina pectoris are characterized by severe coronary artery disease without a therapeutic option for conventional revascularization procedures, only slight impairment of left ventricular systolic function and hyperfibrinogenemia, which results in further enhancement of myocardial ischemia due to microcirculatory impairment of blood flow. In this article data on the anti-ischemic effectiveness as well as first results on the impact of this therapeutic approach on hemodynamics are described. A dose-response study, which compared 3 x 50,000 IU with 3 x 500,000 IU urokinase three times a week over a treatment period of 12 weeks demonstrated subjective as well as objective antiischemic effectiveness. Only patients who were treated with 500,000 IU per injection achieved marked increases in exercise capacity, while some patients in the low-dose group presented even with a deterioration of exercise performance. First hemodynamic studies could not show marked changes of systolic parameters, either at rest or during exercise. But a decrease of pulmonary capillary wedge pressure at rest after treatment with 500,000 IU per injection indicates an improvement of diastolic function as a result of enhanced myocardial perfusion. Echocardiographic measurements of transmitral Doppler flow in 21 patients with end-stage coronary artery disease demonstrated normalization of early and late diastolic filling rates in most cases. These changes were accompanied by a reduction of clinical signs of heart failure. Long-term intermittent urokinase therapy is a valuable approach as it not only improves quality of life during the actual treatment period but by the persistence of therapeutic effects following the cessation of therapy.

Angina Pectoris↗
PubMed1997

Activation of the fibrinolytic system in patients with coronary artery disease and hyperfibrinogenemia.

Elevated fibrinogen levels as well as an impaired activity of the fibrinolytic system are regarded as important cardiovascular risk factors. To elucidate a potential interrelation between fibrinogen as an indicator of a hypercoagulable state and the endogenous fibrinolytic function hemostatic and rheological as well as lipid parameters were determined in 224 consecutive patients, who underwent elective coronary angiography. In the selected study population of 81 men and 19 women with fibrinogen concentration either > or = 3.5 g/l (n = 70) or < or = 2.5 g/l (n = 30) hyperfibrinogenemia was found to be significantly associated with increased concentrations of plasmin-alpha 2-antiplasmin complex [PAP [median (25.-75. percentile)], 534 (361-680) micrograms/l vs. 289 (243-440) micrograms/l; p < 0.001] and tissue plasminogen activator (t-PA) antigen [9 (6-11) micrograms/l vs 8 (5-9) micrograms/l; p < 0.05] while this association was lost in the subgroup of patients with angiographically normal coronary arteries (n = 26). In addition to these findings fibrinogen was significantly correlated with PAP (r = 0.40, p < 0.001; n = 224) and t-PA antigen (r = 0.2, p < 0.01; n = 224) after adjustment for age, diabetes mellitus, lipid parameters and leucocyte counts. It can be argued that elevated fibrinogen levels in patients with coronary artery disease are concomitant with an activation of the fibrinolytic system.

Blood Viscosity↗
PubMed1996

Acute myocardial infarction with origin of the left circumflex coronary artery from the right (anterior) aortic sinus with retroaortic course to the left atrioventricular sulcus.

The case of a 17-year-old boy is described, who had myocardial infarction during scholastic sports 15 minutes after scrotal trauma. Cardiac catheterization revealed a nonstenosed aberrant left circumflex artery originating from the right (anterior) sinus of Valsalva with retroaortic course, which has to be regarded the infarct vessel according to electrocardiographic, ventriculographic, and scintigraphic findings.

Adolescent↗
PubMed1996

Long-term intermittent urokinase therapy in patients with end-stage coronary artery disease and refractory angina pectoris: a randomized dose-response trial.

OBJECTIVES: This dose-response study was designed to test two low dose regimens of urokinase administered over a prolonged time period in patients with chronic refractory angina pectoris with respect to effects on clinical symptoms and objective variables of myocardial ischemia. BACKGROUND: Patients with severe and chronic refractory angina pectoris in end-stage coronary artery disease represent an increasing clinical problem. Favorable therapeutic effects on myocardial ischemia have been reported for long-term application of low dose urokinase. METHODS: Ninety-eight patients with chronic refractory and end-stage coronary artery disease were randomly assigned to two treatment groups: group A (49 patients) received 50,000 IU and group B (49 patients) 500,000 IU of urokinase as an intravenous bolus infection three times a week over a period of 12 weeks. Variables evaluated were number of weekly anginal events, data from ergometric exercise testing with simultaneous electrocardiographic registration, semiquantitative evaluation of Tc-99m 2-methoxy isobutyl isonitrile (MIBI) scans and rheologic variables. RESULTS: After 12 weeks of treatment, anginal symptoms (events/week) were reduced significantly in group B by 70% compared with 24% in group A (p < 0.001). Fibrinogen decreased by 3% in group A and by 33% in group B (p < 0.001). Plasma viscosity and red blood cell aggregation were reduced by 6.4% (p < 0.001) and 19.9% (p < 0.001), respectively, in group B. Objective variables of myocardial ischemia were improved significantly in group B only. No cumulation of coronary ischemic events was observed in group B. CONCLUSIONS: Long-term intermittent urokinase therapy in an applied dose of 3 X 500,000 IU/week represents an effective anti-ischemic and antianginal approach for patients with refractory angina pectoris and end-stage coronary artery disease. Apart from rheologic improvement, antithrombotic properties and plaque regression are likely anti-ischemic mechanisms.

Aged↗
PubMed1996

Chronic-intermittent urokinase therapy in patients with end-stage coronary artery disease and refractory angina pectoris--a pilot study.

Patients with coronary artery disease and severe angina pectoris refractory to conventional medical treatment (beta blockers, nitrates, calcium antagonists) and without the option for invasive revascularization procedures represent an increasing clinical problem. For these patients, chronic-intermittent urokinase therapy has been developed. Twenty patients received 500,000 IU urokinase as intravenous bolus injection 3 times a week over a period of 12 weeks. The average reduction in anginal symptoms in 19 patients was 74%, from 23.5 +/- 10.8 to 5.2 +/- 4.8 events/week (p < 0.001); 1 patient was excluded from further treatment because of an increase of > 66% in anginal events. Fibrinogen decreased by 34% from 370 +/- 57 to 244 +/- 44 mg/dl (p < 0.001), the rheological parameters plasma viscosity by 6.1% from 1.39 +/- 0.04 to 1.31 +/- 0.03 mPas (< 0.001), and red blood cell aggregation by 18% from 13.9 +/- 2.4 to 11.2 +/- 2.2 (p < 0.001). Exercise tolerance increased by 51%. Average ST-segment depression decreased from 0.16 +/- 0.10 to 0.12 +/- 0.09 (p < 0.01). After 12 weeks of follow-up, angina pectoris and fibrinogen levels were still significantly reduced compared with baseline values. Chronic-intermittent urokinase therapy represents an effective anti-ischemic and antianginal approach in patients with refractory angina pectoris and end-stage coronary artery disease. Improvement of rheological blood properties and thrombolytic effects are likely therapeutic mechanisms.

Aged↗
PubMed1996

[Endothelin and big endothelin in coronary heart disease and acute coronary syndromes].

Endothelin (ET), the most potent endogenous vasoconstrictor with mitogenic potency, is generated from its precursor big-endothelin (BET) in a proteolytic process and discussed as a pathogenetic factor in coronary artery disease and in the acute coronary syndromes. Several studies documented elevated plasma endothelin concentrations in acute myocardial infarction, but conflicting results were reported in patients with stable and unstable angina. Only few studies determined big endothelin, although it half-life and plasma concentrations are higher in comparison to endothelin. ET and BET levels (Radioimmunoassay, Biomedica GmbH, Vienna) were determined in patients with stable angina (SAP, n = 20), unstable angina (IAP, n = 12), acute myocardial infarction (AMI, n = 12) and healthy subjects (NP, n = 11). The concentrations of ET and BET (median (minimum-maximum) in fmol/ml) of the patients with stable angina (SAP: ET 0.7 (0.3-1.1); BET 1.7 (0.7-2.9)), unstable angina (IAP: ET 1.0(0.5-1.7); BET 2.5 (1.3-4.1)) and acute myocardial infarction (AMI: ET 1.2 (0.6-2.3); BET 3.6 (3.2-5.3)) showed a significant difference compared to controls (NP: ET 0.5 (0.4-0.7); BET 1.4 (1.1-1.7)) (SAP vs. NP: ET p < 0.01; BET p < 0.05; IAP and AMI vs. NP: ET and BET p < 0.001). Also, the concentrations of the peptides differed significantly dependent on the clinical severity of coronary artery disease (AMI vs. SAP: ET and BET p < 0.001; AMI vs. IAP: BET p < 0.05; IAP vs. SAP: ET p < 0.05; BET p < 0.01). Twelve of 15 patients with big endothelin concentrations over 3 fmol/ml suffered acute myocardial infarction. Seven of 12 patients with AMI showed elevated ET and BET concentrations before the increase of creatinecinase. There was no correlation between number of risk factors per patient, cholesterin and subfractions, severity of CAD classified in one-two-three-vessel disease or coronary score according to modified criteria of the American Heart Association (AHA). We conclude that in patients with coronary artery disease endothelin and big endothelin levels are elevated and related to the clinical and not to the morphological severity of coronary artery disease. Big endothelin is the more sensitive parameter in comparison to endothelin and indicates a severe course of myocardial ischemia in patients with unstable angina. The development of assays with the possibility of a quick determination of the peptides may be valuable for risk stratification of acute coronary events.

Adult↗
PubMed1992

Reduced peripheral and coronary vasomotion in systemic hypertension.

In 53 patients with a history of arterial hypertension and 16 normotensive control subjects, coronary blood flow reserve by means of the argon method, and peripheral vascular flow reserve by means of venous occlusion plethysmography, were studied. The coronary flow reserve, expressed as the ratio of coronary vascular resistance under resting conditions to the minimal coronary vascular resistance after the administration of dipyridamole, was 4.34 +/- 0.89 in the normotensive group and 2.18 +/- 0.60 in the hypertensive group. There was no significant difference in forearm peak flow after 3 min of arterial occlusion between normotensive and hypertensive patients, while the peripheral minimal vascular resistance was significantly higher in hypertensive patients (8.8 +/- 3.8 mmHg x ml.min-1 x 100 ml-1 tissue) as compared to normotensive subjects (6.37 +/- 2.37 mmHg x ml.min-1 x 100 ml-1 tissue). Parallel to the reduction in coronary reserve, the peripheral flow reserve, expressed as the ratio of peripheral resting vascular resistance to peripheral minimal vascular resistance after 3 min of arterial occlusion, was significantly lower (P less than 0.01) in hypertensive subjects (3.85 +/- 2.28) as compared to normotensive subjects (5.31 +/- 1.72). These data suggest that in hypertensives an impaired vasodilator reserve of both coronary and peripheral microcirculation exists.

Angina Pectoris↗
PubMedDate not supplied

Low-dose intermittent urokinase therapy in chronic symptomatic end-stage arterial disease--clinical relevance for patients with coronary artery disease or peripheral arterial occlusive disease.

Symptomatic end-stage arterial disease in coronary artery or peripheral arterial occlusive disease represents an increasing clinical problem as cardiovascular mortality in these patient groups has declined due to improved secondary prevention. While in peripheral arterial occlusive disease amputation with subsequent life-long physical disability is the major problem, patients with end-stage coronary artery disease and refractory angina pectoris repeatedly report to the emergency ward with the clinical symptoms of unstable coronary syndromes, but myocardial infarction is generally ruled out. For these patients long-term intermittent urokinase therapy has been developed as an alternative treatment modality. Potential mechanisms for clinical effectiveness include improvement of rheological blood properties, thrombolysis of non-occluding arterial thrombi and possibly plaque regression. In coronary artery disease urokinase is applied as an intravenous bolus injection of 500,000 IU urokinase three times a week over a period of 12 weeks. This leads to a marked reduction of fibrinogen by about 35% and of clinical symptoms by around 70% accompanied by a reduction of exercise-induced myocardial ischemia. In observational studies in patients with peripheral arterial occlusive disease injections of 500,000 IU of urokinase were usually given daily for a shorter time period of three to four weeks with a clinical success rate, defined as a cessation or marked reduction of rest pain and/or salvage of a limb, of around 50%. Given the state of critical ischemia in both entities of atherosclerotic disease, long-term intermittent urokinase therapy represents a promising antiischemic approach. In particular in patients with peripheral arterial occlusive disease randomized controlled trials with prolonged treatment periods, which are likely to improve clinical results, are warranted.

Arterial Occlusive Diseases↗