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F Dapper

Publications and source records attributed to F Dapper.

At least 19 recordsLinked to original sources
PubMed2001

Endotoxemia and cytokine generation in cardiac surgery in relation to flow mode and duration of cardiopulmonary bypass.

We investigated whether pulsatile flow in cardiopulmonary bypass (CPB), which has been shown to improve intestinal perfusion, reduces endotoxin translocation from the gut and, in consequence, decreases cytokine generation. The study population consisted of 48 adult patients who underwent elective CPB surgery. Pulsatile flow was used during aortic cross-clamping in 24 patients and nonpulsatile flow in 24 patients. Plasma endotoxin concentration increased in all patients during CPB. Significantly (P < 0.05) lower peak levels of 8.25 +/- 1.17 (SEM) pg/mL were reached 30 min after CPB in patients with pulsatile flow in contrast to 11.26 +/- 1.42 pg/mL in patients with nonpulsatile flow. The extent of endotoxemia was not related to the duration of CPB. Following the increase of plasma endotoxin, the concentrations of IL-6 and IL-8 increased with delay of approximately 1 h. The peak levels of these cytokines corresponded significantly (P < 0.005 and P < 0.01, respectively) with duration of CPB, but not with flow mode. Thus, in patients with CPB of more than 97 min (median), IL-6 reached a peak of 335.5 +/- 48.87 pg/mL and IL-8 of 64.86 +/- 24.79 pg/mL in contrast to 210.9 +/- 18.45 pg/mL and 21.2 +/- 10.19 pg/mL, respectively, with bypass times of less than 97 min. The degree of endotoxemia in CPB mainly depends on the quality of tissue perfusion. Cytokine generation, however, is not triggered exclusively by endotoxin, but rather by the trauma of CPB and surgery.

Aged↗
PubMed1999

Selective Cerebral Perfusion Via Innominate Artery in Aortic Arch Replacement Without Deep Hypothermic Circulatory Arrest.

To attain satisfactory results in aortic arch surgery a reliable method of cerebral protection, avoidance of emboli, and control of hemorrhage is mandatory. Deep hypothermic circulatory arrest is the most common technique at present but gives only a limited period of protection, whereas a complicated aortic arch operation may require more time than anticipated. Therefore the selective cannulation and perfusion of the innominate artery has not been widely used until now because it is uncertain whether the left hemisphere of the brain is adequately perfused. Between 1990 and 1995, 21 of 69 patients within the last 36 months, consisting of 15 men and 6 women averaging 45 +/- 13.4 years, underwent operative treatment for aneurysm (n = 9) or type A dissection (n = 12) involving the aortic valve and aortic arch; selective innominate perfusion (SCP [i]) in moderate hypothermia (28 degreesC) for brain protection was used. Extended perioperative monitoring included bilateral somatosensory-evoked potentials (SEP), transcranial Doppler sonography (TCD), a computer-aided topographical electro-encephalometry (CATEEM), and analysis of the arterial and venous oxygen saturation and desaturation. Mean time periods were 229.7 +/- 56.5 minutes for extracorporeal circulation, 151.7 +/- 34.1 minutes for aortic cross-clamping, and 67.05 +/- 34.03 for selective cerebral perfusion via the innominate artery. Not once did the intraoperative monitoring reveal hints of cerebral damage due to inadequate perfusion. All patients survived surgery but two could not be weaned from the respirator; one died 2 days and the other 6 days after the operation due to multiple organ failure (MOF). Another two patients died after 13 days due to untreatable septic syndrome with pulmonary insufficiency. All four patients died within 30 days, during which time they had aortic dissection involving the complete aortic arch and severe aortic valvular incompetence (grade IV). There was no late death and follow-up time of 19.76 +/- 8.04 months revealed an overall mortality rate of 19%. Only temporary neurological affections (left-sided hemiparesis) were found in two patients (9.5%). Additionally, we observed neuropsychological disturbances in one of these. Our first experience with selective cerebral perfusion via innominate artery and the attendant CATEEM monitoring for assessment of adequate bilateral cerebral perfusion suggests that this method is a useful addition to the armamentarium in complicated aortic arch surgery.

Journal Article↗
PubMed1998

[Heart transplantation in infancy: experiences at the Giessen Pediatric Heart Center].

From June 1988 to December 1996 heart transplantations were performed in 36 newborns and infants below one year of age. Diagnosis were hypoplastic left heart syndrome (n = 26), endocardial fibroelastosis (n = 4), cardiomyopathy (n = 3), and other complex congenital heart defects (n = 3). Mean waiting time for transplantation was 52 days, the mean donor-recipient bodyweight ratio was 1.8. Seven patients (19%) died after transplantation mainly within the first month after transplantation. The cumulative probability of survival is 79% in all patients. The influence of increasing experience is indicated when patients transplanted from 1988-1993 (n = 15) are compared with transplants from 1994-1996 (n = 21). The overall survival in the first group was 50%, whereas patients transplanted from 1994 showed a probability of survival of 92%. The 1-year survival rate in the later group was 100%. In 20 patients a total of 31 rejection episodes were observed. 2 infants died due to rejection. 71% of all rejections occurred during the first month after transplantation. Renal function was slightly impaired one year after transplantation in all patients without tendency for deterioration in the sequel. The somatic development is normal in nearly all infants and the quality of life is excellent. All infants live at home without any restrictions. Two patients, however, suffer from a neurologic deficit. Until now there is no evidence of coronary vascular disease or malignancy. Heart transplantation is in our opinion a reconsiderable alternative in the treatment of complex cardiac disease and cardiomyopathy in infants.

Cause of Death↗
PubMed1998

[Status of intensified therapy and regionalized allocation of donor hearts in the management of patients with terminal heart failure].

BACKGROUND AND OBJECTIVE: The medical management of heart failure improved greatly during the last decade. Heart transplantation (HTx) as surgical alternative is an established measure but operation numbers stagnated due to the lack of donor organs and still the 1 year mortality is about 20%. Rising numbers of new registrations led to long waiting lists with a high mortality rate. Solutions are intensified therapeutic concepts and improvements in organ allocation. This study was done to show if a combined intensified medical management and a regional donor allocation system may improve outcome in heart transplant candidates. PATIENTS AND METHODS: A cohort of 396 elective candidates for heart transplantation from the years 1984-1997 without contraindications and at least in NYHA stage III at entry were investigated for total mortality, modes of death and the probability of heart transplantation. Patients were divided in two groups (group A: submitted from 1984-1994, n = 256, group B: 1995-1998, n = 150). RESULTS: The groups were comparable in clinical and hemodynamic baseline characteristics. Patients of group B had a better long-term prognosis after 2 years (87% versus 73.5%, p = 0.009) and had a significantly lower rate of heart transplantation (HTx rate in group A and B after 2 years: 35% and 15%, p = 0.002). Only two patients died due to heart failure in the years 1995-1998 compared to 20 heart failure death from 1984-1994. The waiting time for a donor heart fell from 81.8 +/- 80 days in group A to 22.1 +/- 21 days in group B. The main problem is the unchanged sudden death rate in patients with stable hemodynamics prior to the event. CONCLUSIONS: A combination of tailored medical therapy for heart failure plus regionalization of donor heart allocation with short waiting time seems to be the best way to treat patients with end-stage heart failure. A specialized cardiomyopathy program is necessary for such an approach. Sudden death in heart transplant candidates has to be studied more intensively.

Adult↗
PubMed1998

Clinical experience with heart transplantation in infants.

OBJECTIVE: Orthotopic heart transplantation has become an accepted therapeutic concept for adult patients with endstage heart disease. In newborns and infants this procedure is still a matter of discussion because of unknown long-term results and the lack of donor organs. METHODS: Since March 1988 we have performed 40 orthotopic heart transplantation in 39 infants who were from 1 to 280 days of age. Indications for transplantation included hypoplastic left-heart syndrome (n = 28), dilative cardiomyopathy (n = 4), endocardial fibroelastosis (n = 4) and other complex structural anomalies (n = 3). The mean waiting period for transplantation was 53 days. A donor-recipient weight ratio up to 4.0 was accepted. Profound hypothermic circulatory arrest was used for graft implantation in all those patients who required extensive aortic arch reconstruction (71%). The initial immunomodulation was based on Cyclosporine, Azathioprine and Prednisolone. Patients who underwent transplantation during the first 6 weeks of life received a chronic single-drug therapy with Cyclosporine after 1 year. RESULTS: There were six peri-operative deaths caused by drug-resistant right-heart failure in three cases, humoral rejection (n = 1), CMV infection (n = 1) and multi organ failure (n = 1). One infant died late, due to rejection. The actuarial survival rate for the entire group is now 82%. There is a remarkable influence of increasing experience. Whereas six of 15 infants who had heart transplantation between 1988 and 1993 died early post-operatively (survival rate: 60%), only one late death occurred among 24 recipients in the period from 1994 to April 1997 (survival rate: 96%). Episodes of rejection occurred once or several times in about half of the patients in this series (48%). All surviving children are living at home in excellent condition. CONCLUSIONS: Heart transplantation during early infancy is a rational and durable therapy for heart diseases with irreversible myocardial failure or severe structural anomalies. The intermediate-term results have been encouraging in many centers, but more data must be accumulated to determine the sequelae of chronic immunosuppression. The lack of donor organs remains one of the major problems in pediatric heart transplantation.

Body Height↗
PubMed1998

An assessment of selective cerebral perfusion via the innominate artery in aortic arch replacement.

Maintaining an adequate cerebral oxygen supply is a serious problem in aortic arch surgery. Deep hypothermic circulatory arrest is the most common method used for cerebral protection, but guarantees only a time-limited safety period. Based on experimental investigations, we applied selective cerebral perfusion via the innominate artery alone with only moderate hypothermia (28 degrees C) and without circulatory arrest in 25 consecutive patients undergoing surgical treatment of an aneurysm (n = 10) or acute type-A dissection (n = 15) involving the aortic valve and arch. In every case a test perfusion was carried out to assess whether the cerebral perfusion achieved would be adequate for the whole operation. In no case was the perfusion inadequate. As a new perioperative monitoring system, we used computer-aided topographical electroencephalometry (CATEEM). There were 18 male and 7 female patients, their age was 47.0 +/- 15.1 years (mean +/- SD). Mean time periods were 155.1 +/- 37.3 min for aortic cross-clamping, and 69.3 +/- 35 min for selective cerebral perfusion. Postoperatively, two patients (8%) revealed a temporary left-sided hemiparesis, and 4 patients (16%) died within 30 days. The overall mortality rate was 16% in a follow-up period of 24.2 +/- 9.5 months. In this small group the CATEEM monitoring enabled an intraoperative selection of patients with sufficient bihemispheric collateral circulation and therefore suitable for simple innominate artery perfusion.

Acute Disease↗
PubMed1998

Superficial femoral vein in arterial reconstruction for limb salvage: outcome and fate of venous circulation.

BACKGROUND: In some particular cases in vascular surgery it is mandatory to perform arterial reconstruction using autologous graft. Since 1985, we have been using the superficial femoral vein for arterial substitute in the case of limb salvage, when another autologous vein has not been available. We made a prospective investigation on 32 patients over a mean period of 24.5+/-12.1 months (1 to 48 months) to evaluate the usefulness of superficial femoral vein (SFV) for distal arterial reconstructive surgery and to objectify the fate of venous circulation of the limb after removal of this vein. METHODS: There were 20 male and 12 female patients averaging 64.3+/-10.3 years, who underwent crural arterial reconstructive surgery using the composite technique (PTFE and SFV). All grafts had been placed subcutaneously in lateral to knee position. Mean length of removed superficial femoral vein was 13.2+/-9.4 cm. RESULTS: In 6 patients (18.7%), we found an early occlusion of bypass followed by major amputation in 5 cases (15.6%). Minor amputation had to be done in 12 patients (37.5%). Cumulative patency was 56.3% after 48 months. Following the removal of superficial femoral vein, we had no complications due to venous stasis. We found a significant increase of plethysmographically measured venous capacity (1.7+/-0.49 to 2.51+/-0.71 [p<0.01]) and venous outflow (14.9+/-5.34 to 23.9+/-10.4 [p<0.05]) after 7.7 months. We did not observe more significant changes of venous circulation during further follow-up. CONCLUSIONS: Despite overall good results, we only recommend the use of superficial femoral vein in hazardous situations, when other autologous material is not available.

Amputation, Surgical↗
PubMed1998

Coarctation of the thoraco-abdominal aorta: operative treatment with a cryopreserved arterial homograft in a seven-year-old boy.

Compared to coarctation in the proximal descending aorta near the insertion of the ligamentum arteriosum, coarctation in the aortic arch, the lower descending or the abdominal aorta is a relatively rare disease. Operative treatment of abdominal coarctation is more complicated if there are concomitant stenoses of visceral or renal arteries. In young patients, surgical procedure and outcome is additionally determined by caliber and compliance mismatch between still growing native vessels and arterial substitute. Our report deals with a seven-year-old male patient, who was first diagnosed as having coarctation of the aorta at five years of age due to distinct bilateral brachial hypertension. The angiogram revealed a narrowing of the aorta, approximately ten centimeters in length, from the lower descending segment down to the proximal abdominal part of the aorta. The origin of the superior mesenteric artery and both renal arteries were not involved in the pathological process. Arterial reconstruction was carried out by anastomosis of cryopreserved arterial homograft with the thoracic aorta and with the abdominal aorta distal to the origin of the renal arteries. The postoperative course was uneventful, duplex sonography revealed no pressure gradient between the thoracic and abdominal aorta and brachial blood pressure was within normal ranges.

Aorta↗
PubMed1997

Effect of bradykinin B2-receptor antagonism on post-ischemic coronary reperfusion.

Isolated rabbit hearts in a modified Langendorff preparation were used to study the role of bradykinin B2-receptor antagonism on recovery from cardiac ischemia. The experiments were performed to clarify a potential risk of administrating BK-receptor antagonists in patients with coronary heart disease and patients undergoing heart surgery. The hearts were perfused in an open system at a constant pressure of 70 mm Hg and at a constant temperature of 37 degrees C with Krebs-Henseleit-buffer solution containing 6.5% HAES (hydroxyethyl-amylopectin) and 10 mmol Na-pyruvate/l. The perfusate was equilibrated to a PO2 of about 500-600 mm Hg. After a steady state period of 30 min, coronary perfusion was stopped for 30 min and the hearts were subsequently reperfused for further 30 min. Pretreatment with the B2-receptor antagonist, CP-0127, significantly increased (p < 0.001) the coronary vascular resistance during reperfusion from 31.9 +/- 2.1 to 59.0 +/- 6.5 mm Hg/ml/min/10 g wt and decreased the left ventricular pressure amplitude to 44.0 +/- 15.2% (p < 0.005) of it's baseline. When ischemia was combined with hyperkalaemic cardioplegia, CP-0127 did not influence coronary vascular resistance, but depressed, only to a minor degree, left ventricular pressure amplitude to 65.1 +/- 15.4% (p < 0.005) during reperfusion. Arrhythmias during reperfusion with cardiac arrest occurred only in 2 hearts with B2-receptor inhibition when ischemia was not combined with cardioplegia. Dependent on the initial functional status of the heart B2-receptor inhibition impaired recovery from acute coronary ischemia by increasing the coronary vascular resistance and depressing the myocardial function and therefore may constitute a risk in patients undergoing heart surgery and extracorporeal circulation.

Analysis of Variance↗
PubMed1997

The influence of acute preoperative plasmapheresis on coagulation tests, fibrinolysis, blood loss and transfusion requirements in cardiac surgery.

OBJECTIVE: Withdrawal of autologous plasma and reinfusion after cardiopulmonary bypass (CPB) offers the opportunity of improving patients' haemostasis and reducing homologous blood consumption in cardiac surgery. The influence of acute, preoperative plasmapheresis (APP) on coagulation tests, fibrinolysis, blood loss and transfusion requirements was investigated in elective aortocoronary bypass patients. METHODS: Forty patients were randomized to a control or pheresis group. The pheresis group had platelet-rich plasmapheresis (PRP-group, n = 20) performed before incision and the platelet-rich plasma (PRP) was returned after CPB. The control group (n = 20) was managed without pheresis. All patients had serial coagulation studies, including prothrombin split products (F1/F2), fibrinopeptide A (FPA), protein C (PC), thrombomodulin (TM), tissue-plasminogen-activator (t-PA), plasminogen-activator-inhibitor (PAI 1), fibrinopeptide B beta 15-42 (FPB beta 15-42), haemoglobin and platelet counts determined intra- and postoperatively. Chest tube drainage and transfusion requirements were recorded. RESULTS: APP had no negative effects on the quality of PRP. The platelet count of the withdrawn autologous plasma was 239 +/- 33 x 10(9)/l. From the end of the operation (after retransfusion of autologous plasma) until the first postoperative day platelet counts were significant higher in the PRP-group (P > 0.05). Plasma concentrations of modified antithrombin III (ATM), F1/F2 and FPA increased (166-290% from baseline) and PC- and TM-antigen decreased (11-49% from baseline) to a different extent for both groups throughout CPB. t-PA-activity increased intraoperatively peaking at the end of CPB (PRP-group: 4.8 +/- 0.8 IU/ml, control-group: 8.1 +/- 2.3 IU/ml)(P > 0.05). With onset of CPB PAI-1 levels decreased and were further reduced after CPB in control patients in comparison to PRP-patients (P < 0.05). FPB beta 15-42 occurred in peak concentrations after neutralisation of heparin by protamine. Only PRP-patients showed baseline values of coagulation and fibrinolytic parameters on the next morning (P < 0.05). Total postoperative blood loss during the first 24 h was 503 +/- 251 ml (PRP-group) and 937 +/- 349 ml in the control-group (P < 0.05). None of the PRP-patients received allogeneic blood, whereas five control-patients received 11 units of packed red cells (P < 0.05). CONCLUSIONS: The findings suggest that in elective cardiac surgery heparin cannot prevent generation of both thrombin and fibrin, born throughout CPB and postoperatively. The use of PRP withdrawn immediately preoperatively is an attractive technique to reduce allogeneic blood usage and preoperative blood loss, especially in patients in whom withdrawal of autologous whole blood cannot be performed.

Aged↗
PubMed1997

Potential problems with simplified selective cerebral perfusion--experimental investigations and clinical improvements.

Currently the most used perfusion techniques during aortic arch surgery to prevent cerebral damage include hypothermic circulatory arrest, retrograde cerebral perfusion and selective cerebral perfusion (SCP). The application of simplified SCP, which does not require deep hypothermia, has become an alternative procedure for brain protection. Including the physiological principle of autoregulated cerebral blood flow, cerebral perfusion flow is not predetermined, but differentiated from the different cannula sizes for the lower and upper body perfusion. In a mock circulation loop, we could show that resistance changes in the two compartments led to flow shifts between the systemic and brachiocephalic regions. In addition to mechanical factors cerebral perfusion is determined from physiological changes. In practice, these shifts can be initiated with disrupted autoregulation due to ph-stat management or dramatic pressure changes. To prevent mismatched cerebral perfusion extended perioperative monitoring was included in our clinical setting. With bilateral somatosensory evoked potentials, a computer aided topographical electroencephalometry system, transcranial doppler-sonography and jugular venous bulb saturation, we could provide a sufficient bihemispheric perfusion. Between 1990 and 1995 we operated on 21 patients using SCP. Intraoperatively no signs of cerebral ischaemia due to inadequate perfusion could be observed. Only temporary neurological changes were found postoperatively. In summary, the simplified SCP, despite its physiological basis, is intricately involved in control and influence. We think that the application of SCP is safe if extended neurophysiological monitoring is included in the clinical setting.

Cerebrovascular Circulation↗
PubMed1997

Perioperative management of pulmonary hypertension after heart transplantation in childhood.

BACKGROUND: Pulmonary hypertension is responsible for a substantial part of perioperative and postoperative mortality and morbidity after cardiac transplantation. Treatment of right ventricular failure after increased pulmonary vascular resistance is difficult especially in infants and children. Therefore we started a preventive therapy of pulmonary hypertension after cardiac transplantation to avoid right ventricular failure and compared the results with a group of patients with conventional therapy. METHODS: Group 1 (n = 13), with transplantation from 1988 to 1991, was treated with vasodilators when symptoms of right ventricular failure developed. Group 2 (n = 19) had preventive treatment with prostaglandin E1 (PGE1), the phosphodiesterase-III inhibitor enoximone, and alkalinazation starting during weaning from cardiopulmonary bypass. RESULTS: Six patients in group 1 died; four of them as the result of right ventricular failure in the immediate postoperative course despite aggressive treatment. In group 2 there were three deaths as the results of rejection (2) and infection (1). None of these patients developed right ventricular failure (p = 0.02). Cold ischemic time, extracorporeal circulation time, and waiting time before transplantation were significantly longer in group 2. Side effects of this preventive therapy were not observed. CONCLUSIONS: We conclude that prophylactic therapy of pulmonary hypertension with vasodilators in infants and children after heart transplantation is safe and effective in preventing right ventricular failure in the postoperative course.

Alkalies↗
PubMed1996

[NO inhalation in heart surgery procedures: relevance for right heart function?].

UNLABELLED: The right ventricle is more jeopardized by a cardiopulmonary bypass than the left one. Impaired right ventricular performance may profit from an afterload reduction. A selective reduction in pulmonary artery pressure (PAP) or pulmonary vascular resistance (PVR) without impairment of the systemic circulation seems to be possible by inhalation of nitric oxide (NO). Therefore in the present study we looked for influences of NO inhalation on PAP, PVR and right heart parameters immediately after weaning from the bypass. The dependence of endothelial function on age, preoperative heart function and extracorporeal circulation is well established. The relevance of such parameters on NO inhalation was also investigated. METHODS: After ethical approval and informed consent were obtained, 20 patients with moderately increased PAP were included in the study. Ten patients inhaled NO at a concentration of 30 ppm; the other group served as a control group. Measurement points were 10 min after the end of extracorporeal circulation (baseline), 3, 10, and 20 min after the start, as well as 10 min after the end of NO inhalation. NO was injected near the tube into the tubing system during inspiration; dosage and monitoring of the concentration were achieved by means of a chemiluminometer. Measured parameters consisted of PAP, PVR, right ventricular ejection fraction and volumes, systemic blood pressure and resistance, central venous pressure, pulmonary capillary wedge pressure, and oxygenation parameters (paO2, pvO2, paCO2). RESULTS: The decrease in PAP (from 29.7 +/- 3.9 to a minimal 25.4 +/- 4.3 mm Hg, P < 0.005) and in PVR (from 169.4 +/- 51.9 to a minimal 116.3 +/- 60.9 dyn.s.cm-5, P.0.05) did not improve right heart function. A similar significant increase in SVR was observed in the NO group and in the control group. Age, haemodynamic parameters or duration of the ischaemic phase of the cardiopulmonary bypass did not influence the course of PAP or PVR. Changes in PAP (from 30.0 +/- 4.0 to a minimal 26.7 +/- 3.6 mm Hg, P < 0.05) and PVR (from 149.0 +/- 41.5 to a minimal 125.2 +/- 51.5 dyn.s.cm-5, in the control group were not statistically different from those in the NO group. Indicators of intoxication like an increase in NO2 or methaemoglobin concentrations or changes in compliance or resistance were not observed. CONCLUSIONS: Patients with moderate pulmonary hypertension did not profit from NO inhalation immediately after weaning from the cardiopulmonary bypass. The decreases in PAP and PVR found in the NO or control group did not improve right-heart function. When the NO and control group were compared, specific effects of NO inhalation on PAP and PVR must be questioned. This could perhaps be explained by data from animal experiments, which found high endogenous NO levels in situations with elevated cytokine levels. Cytokines are increased after extracorporeal circulation. Oxygenation was not impaired by inhalation of relatively high concentrations of NO. For all investigations with NO inhalation not preceded by steady-state conditions, a control group is recommended.

Aged↗
PubMed1996

Transcranial Doppler detection of microemboli in prosthetic heart valve patients: dependency upon valve type.

Transcranial Doppler ultrasound has revealed the existence of cerebrovascular microemboli in asymptomatic patients with prosthetic heart valves. We investigated the relation between the presence and number of emboli signals and valve type. Patients with six types of prosthetic valves (Björk-Shiley monostrut, Medtronic-Hall, Carbomedics, ATS, Carpentier-Edwards standard, Carpentier-Edwards supraannular) were examined using transcranial Doppler ultrasound in two centers. The monitoring time was 30 min over the right middle cerebral artery. All patients were stabilized on warfarin at the time of study. Microemboli signals were identified by their characteristic audiovisual signal and on subsequent spectral analysis, based on accepted criteria. A standard neurologic questionnaire was completed by all patients. The prevalence of microemboli signals varied between 49% (Medtronic Hall) and 97% (Björk-Shiley monostrut), while their number varied between 1 [0-3] (Carpentier-Edwards standard) and 187 [136-240] (Björk-Shiley monostrut) per hour (median and 95% CI). Both parameters were significantly higher in patients with Björk-Shiley monostrut valves compared to the other patient groups. There were no significant differences in the prevalence of neurologic complications among the groups examined (overall 16%), or in emboli numbers between symptomatic and asymptomatic patients. The prevalence and quantity of microemboli signals in patients with prosthetic heart valves, as detected by transcranial Doppler, is dependent upon valve type. The clinical significance of these microemboli signals remains to be further evaluated.

Aged↗
PubMed1996

Endothelin plasma levels during heart surgery: influence on pulmonary artery pressure?

OBJECTIVE: Some studies found endothelin-1 to be a trigger for pulmonary hypertension. Endothelin-1 is an endothelial derived substance with generally vasoconstrictive properties, but probably vasodilatory effects on pulmonary arteries. The aim of the present study was to look for influences of endothelin-1 plasma values on pulmonary artery pressure. METHODS: Endothelin-1 levels during and after cardiac surgery and correlations to pulmonary artery pressure were tested in 10 control patients and 21 patients with pulmonary hypertension (mean pulmonary arterial pressure > 20 mmHg, systolic pulmonary arterial pressure > 30 mmHg). RESULTS: According to endothelin-1 values before anaesthesia (normal value below 4 pg/ml) patients with pulmonary hypertension could be divided into a "high endothelin-1" (10 patients, mean 8.25 +/- 2.06 pg/ml) and a "normal endothelin-1" (11 patients, mean 2.13 +/- 0.86 pg/ml) subgroup (p < 0.01). Values of the "high endothelin-1" group decreased until end of operation (from 7.58 +/- 2.35 to 2.95 +/- 1.44 pg/ml, n = 6) when pulmonary artery pressure returned to normal. Otherwise they slightly increased (from 9.43 +/- 2.24 to 11.07 +/- 1.96 pg/ml, n = 4). Levels of the "normal endothelin-1" group increased (to 2.55 pg/ml). Endothelin-1 values peaked on the intensive care unit (ICU) in all patients. Baseline endothelin-1 and systolic pulmonary artery pressure values correlated well with each other (r = 0.73, p < 0.001). Endothelin-1 decreased after extracorporeal circulation in all patients in whom pulmonary artery pressure tended to normalise, whereas no rise in pulmonary artery pressure paralleled the marked increase in endothelin-1 on the ICU. Vasodilatory effects of endothelin on pulmonary arteries can attribute to this course. CONCLUSIONS: Endothelin-1 seems not to trigger pulmonary hypertension but rather to vasodilate pulmonary vasculature.

Aged↗
PubMed1996

Factor XIII in ulcerative leg disease: background and preliminary clinical results.

The therapy concept of topical factor XIII application was developed on the basis of clinical and experimental investigations on improvement of wound healing, as well as on the morphological and pathophysiological topical site of venous ulcers. Topical treatment with factor XIII is special with regard to mode of application as well as efficacy, since a lot of other medications used for local wound treatment contain a fibrinolytic component. In the last 32 months, 23 inpatients (17 female, 6 male) averaging 62.9 +/- 14.1 years and suffering ulcerative leg disease were treated with topically applied factor XIII. The average period of distal venous ulcer in these patients was 3.3 +/- 2.04 years. The extent of the ulcer surface ranged between 2.5 x 3.0 cm (minimum) and 18.5 x 8.0 cm (maximum). All patients had been in medical consultation for several years. The venous ulcers were based upon a "postthrombotic syndrome" in 15 patients. Six patients were suffering from ulcerations due to arterial and venous mixed disease, and there were 2 patients with ulcerations of unknown etiology. In 5 patients, 2 with unknown etiology and 3 with arterial and venous mixed disease, local treatment with factor XIII was discontinued after 4 weeks because there was definitely no improvement in wound healing. Additionally, 3 patients with ulcerations due to arterial and venous mixed disease were treated for a maximum of 6 weeks with only moderate improvement in healing. Twelve of the 15 patients (79.3%) with extended, chronic ulceration on the basis of a postthrombotic syndrome showed such a distinct improvement of topical site after an average of only 3.15 +/- 1.14 weeks that they were released for further ambulatory treatment. Three patients had to be treated for a maximum period of 6 weeks, also with distinct improvement in wound healing. Apart from a wound surface reduction and a clinically documentable improvement of granulation tendency, there was a marked reduction of secretion and bleeding tendency within the ulcer area observed in all patients. None of the patients showed any systemic or local allergic reactions.

Administration, Topical↗
PubMed1996

Comparison of different prophylactic myocardium saving measures during heart surgery. Effects on perioperative troponin-T levels.

OBJECTIVE: Different prophylactic myocardium saving strategies are often routine in open heart surgery. Even if theoretically well established, they must be critically reviewed in times of limited financial resources. EXPERIMENTAL DESIGN: Troponin-T (TnT) is a valuable tool to detect even minor myocardial damages independently from concomitant muscle injuries. We measured intra- and postoperative TnT-values and ST-wave deviations on the ECG in a control group and in patients receiving one of the following prophylactic MEASURES: hypothermia during cardiopulmonary bypass (CPB), nitroglycerine ([0.5 microgram/kg/min]) or nifedipine [0.1 microgram/kg/min] after aortic cross-clamping until end of operation, or perioperative Mg2+ per os. PATIENTS AND SETTING: The study included 65 patients of a university hospital with preoperative good heart function scheduled for elective aorto-coronary bypass operation. RESULTS: TnT values increased in all groups after CPB and peaked between end of operation and first post-operative day. TnT values above the critical border of 1.0 microgram/l in the early period after CPB were less often seen in the nitroglycerine and nifedipine group. No pronounced differences could be observed after the first postoperative day. Patients of the hypothermia group had most often TnT values above 1.0 microgram/l. Maximum TnT values of the control, the hypothermia and the Mg(2+)-group correlated with the duration of aortic-crossclamping. No correlation existed between ST-deviations and TnT-values. CONCLUSIONS: The prophylactic measures failed to reduce myocardial damage as evidenced by the course of TnT values. They can therefore not be recommended as routine strategies in patients with good left heart function. Especially hypothermia should be considered carefully.

Aged↗