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J Ennker

Publications and source records attributed to J Ennker.

At least 19 recordsLinked to original sources
PubMed2006

[Should we avoid cardiopulmonary bypass with diabetic patients?].

In the peri-operative and post-operative course of coronary bypass operations, the diabetic patient is susceptible to complications that cause morbidity and mortality. Morbidity might best be conceptualized as the cumulative effect of the diabetic patient chronically at risk and a variety of surgically related insults, including surgical stress, anaesthesia, hypo- and hypertension, anaemia, dysrhythmias, de- or hyperhydration and cardiopulmonary bypass (CPB) that exceed the compensatory capacities of the patient. Because all these factors for adverse outcome coexist, it becomes difficult to determine which ones are most important. However, it is reasonable that, in the presence of generalized atherosclerosis affecting the aorta ascendens, carotids and the cerebral arteries, the interaction of CPB-associated embolization, hypoperfusion and inflammation may cause neurologic morbidity. Many physiologic alterations (such as non-pulsatile perfusion and hemodilution) occur during CPB and may worsen renal dysfunction in patients with diabetic nephropathy. Pulmonary dysfunctions, associated with diabetic microangiopathy, could be unmasked by atelectasis, capillary leak and other pathophysiological conditions developing after the use of extracorporeal circulation. Actually, there is evidence that with the avoidance of CBP and the use of adequate OPCAB (Off Pump Coronary Artery Bypass) techniques, by experienced teams, the incidences of neurological, renal and pulmonary complications decrease, in high-risk patients, e. g. diabetics, as well as in unselected cohorts. Because it is not possible to identify confidently those patients who are at risk for CPB-associated complications, we use a strategy where all CABG (Coronary Artery Bypass Grafting) are performed in OPCAB technique. The total OPCAB approach will in addition ascertain the development of organizational OPCAB routines and expertise. The process of re-engineering the unit towards total OPCAB needs systematic training and re-training of cardiac surgeons by surgeons, experienced in both, OPCAB surgery and knowledge transfer, according to the principles of continuing medical education (CME). Thus, the chances of the OPCAB technique improving the outcome of diabetic patients can be fully realized.

Atherosclerosis↗
PubMed2006

[Experiences collected in more than 2,300 diabetics undergoing coronary artery bypass grafting: patients with a specific risk profile].

BACKGROUND: The objective of this paper was to analyze demographic and clinical characteristics of diabetic patients undergoing coronary artery bypass grafting on the basis of a significant number of cases. METHODS: The data of 8,195 patients who have undergone coronary bypass operations between 1996 and 2003 were analyzed. Non-diabetic patients (no DM), oral treated diabetics (DM oral) and insulin-treated diabetics (DM insulin) were compared in terms of their pre-operative, intra-operative and post-operative characteristics. The statistical analyses were performed with the support of SPSS 11.5 under application of chi-square and student-t tests. RESULTS: In cardiosurgery, diabetics differ in various ways from non-diabetic patients. They show a significantly higher prevalence of the known cardiovascular risk factors such as raised body mass index, age and hypertension. Furthermore they present a higher prevalence of vascular comorbidity such as peripheral vascular disease and carotid disease. At the postoperative stage, cerebral dysfunction occurred more often among the diabetic patients (no DM 5.2% vs. DM oral 7.3% vs. DM insulin 10.5%; p < 0.05), they suffered from apoplexies more frequently (no DM 1.9% vs. DM oral 2.1% vs. DM insulin 3.2%; p < 0.05), and they required re-intubation more frequently (no DM 2.6% vs. DM oral 3.1% vs. DM insulin 5.6%; p < 0.05). Peri-operative mortality was highest in the group of insulin-treated diabetics (no DM 1.1% vs. DM oral 1.6% vs. DM insulin 1.8%; p < 0.05). CONCLUSION: In coronary surgery, diabetic patients represent an especially challenging patient group with an independent risk profile, who require specific consideration as far as the selection of the operative approach, on, one hand, and the post-operative follow-up, on the other hand, are concerned.

Age Factors↗
PubMed2006

Fracture of Colvin-Galloway-Future band in a patient with mitral valve annuloplasty.

Annuloplasty with various annuloplasty ring systems is a fundamental part of mitral valve repair and has been frequently performed since its introduction by Carpentier in 1969. Due to the different advantages or disadvantages of each system, some controversies exist regarding the best type of ring annuloplasty support. Here we describe, for the first time, the case of a female patient in which a fracture of a semi-rigid open annuloplasty ring occurred, leading to annular deformation and mitral regurgitation.

Aged↗
PubMed2005

Intraoperative bypass flow measurement reduces the incidence of postoperative ventricular fibrillation and myocardial markers after coronary revascularisation.

OBJECTIVE: Sudden ventricular fibrillation (VF) and myocardial infarction (MI) are life-threatening complications after coronary artery bypass grafting (CABG). We prospectively analysed the impact of intraoperative bypass flow measurement with the transit time flow Doppler method (TTFD) on the incidence and outcome of postoperative VF and MI. METHODS: In 1995 a standardized algorithm for the treatment of postoperative VF was introduced in our institution. The rate of postoperative VF was therefore exactly registered. In 1998 the TTFD method was implemented as a standard in all CABG cases. Whenever insufficient bypass graft flow was detected, anastomoses were redone and technical problems affecting the grafts were excluded. The incidence of postoperative VF and CK/CK-MB fraction was observed prospectively and the new data was compared to the data from 1995 to 1998. RESULTS: From 1/95 to 7/98 a total of 4321 patients (group A) were operated on with isolated CABG procedures using extracorporeal circulation. In the period from 8/98 to 10/02 a total of 3421 patients (group B) was operated on with isolated CABG procedures under the same conditions, except that the TTFD method was used in every case. The treatment of VF was standardised in both groups according to the algorithm. The most striking effect was the significant reduction of VF from 0.66% to 0.44% when TTFD was introduced and the steep decrease in mortality from 30% to 12.2% in patients with VF when the algorithm and TTFD were routinely applied. Furthermore the rate of insufficient bypass flow detected by angiography was reduced by 66%. CONCLUSION: Routinely the use of TTFD significantly reduced the incidence of postoperative VF, postoperative CK/CK-MB fraction, and angiographically detected bypass malfunction. A simultaneously implemented algorithm reduced the mortality with VF after CABG. The consequent use of TTFD intraoperatively reduced the incidence of postoperative anastomosis and technically related complications of bypass surgery and led to a significant reduction of postoperative mortality in CABG procedures.

Algorithms↗
PubMed2005

Mid term outcome and quality of life after aortic valve replacement in elderly people: mechanical versus stentless biological valves.

OBJECTIVE: To assess the benefit for patients older than 65 years of aortic valve replacement with stentless biological heart valves in comparison with mechanical valves. DESIGN: Multiple regression analysis of a retrospective follow up study. SETTING: Single cardiothoracic centre. PATIENTS: Between 1996 and 2001, 392 patients with a mean age of 74 years underwent aortic valve replacement with stentless Freestyle bioprostheses or mechanical St Jude Medical prostheses. MAIN OUTCOME MEASURE: Operative mortality and morbidity, postoperative morbid events, mid term survival, and New York Heart Association (NYHA) class improvement, and quality of life. RESULTS: No significant differences were found between patients receiving stentless biological valves and patients receiving mechanical prostheses. However, analysis of subgroups showed that patients older than 75 years with mechanical valves had an increased risk of major bleeding events (p = 0.007). Patients requiring anticoagulation by means of coumarin had a twofold increased risk of an impaired emotional reaction (p = 0.052). However, for patients who received a mechanical valve for severe combined aortic valve disease a survival advantage (p = 0.045) and a decreased risk of prolonged ventilation (p = 0.001) was observed. On the other hand, patients receiving a stentless bioprosthesis had an increased risk of a prolonged stay in intensive care (p = 0.04) and stroke (p = 0.01) if they had severely reduced cardiac function (NYHA class IV). CONCLUSIONS: Elderly people receiving stentless bioprostheses benefit emotionally because of the avoidance of coumarin. However, in patients with severe hypertrophied ventricles and extraordinary calcifications, stentless bioprostheses should be chosen with caution.

Aged↗
PubMed2004

On-line variable live-adjusted displays with internal and external risk-adjusted mortalities. A valuable method for benchmarking and early detection of unfavourable trends in cardiac surgery.

OBJECTIVE: Benchmarking and early detection of unfavourable trends. METHODS: We implemented a dedicated project-orientated data warehouse, which continuously supplies data for on-line computing of the variable live-adjusted displays (VLADs). To calculate the expected cumulative mortality, we used the multi-variate logistic regression model of the EuroSCORE model. In addition to the external EuroSCORE standard, we calculated a centre-specific risk score for internal standards by analysing the data of 9135 patients, which enables both internal and external comparisons. The VLADs are embedded into the multi-purpose web-based information portal, so that the physicians can investigate several types of VLADs interactively: performance of different types of surgery and individual surgeons for different time intervals. We investigated clinically important events such as modification of operative techniques and personnel changes of the team by the VLADs. RESULTS: We found transient declines in the performance curves during major changes in patient management, indicating that systemic--rather than accidental or patient related factors--were involved in the mortality risk. The internal standard line represents these clusters more clearly than the external line. We evaluated examples of how periods of increased risk could be monitored by the VLAD curves: (1) the introduction of OPCAB surgery; (2) training of surgeons; (3) staff changes and staff-related management. CONCLUSIONS: On-line VLADs based on a day-to-day updated database, displaying both internal and external standards, are a helpful visualisation tool for earlier detection of unfavourable trends. They enable the surgeon teams and clinical management to take countermeasures at an early stage.

Benchmarking↗
PubMed2004

Diabetes mellitus in coronary artery surgery: therapeutic strategies in the light of recent studies.

Advances in percutaneous coronary revascularization have meant that, increasingly, patients with multivessel diseases are initially treated with the methods of interventional cardiology. Ongoing studies involving new stent coatings and optimized anti-thrombotic therapies could help to lower future restenosis rates and improve the success rate of stenting. Thrombocyte glycoprotein IIb/IIIa receptor blockers have already been shown to reduce the rate of acute PTCA complications in high-risk patients and could have a sustained impact on the long-term prognoses for PTCA patients. However, for diabetic patients with coronary multivessel diseases, coronary artery bypass grafting using arterial grafts as the initial revascularization method must be given preference over other therapy methods. Consequently, this group of patients is bound to grow in importance in cardiac surgery. The advances made in percutaneous coronary revascularization and in coronary surgery call for further prospective, controlled, randomized clinical studies in order to establish the best possible treatment strategy for patients with diabetes. It should be noted, however, that the therapeutic effect of myocardial revascularization is generally limited to individual coronary-arterial segments, whereas the pathological process of atherosclerosis is rather diffuse. The surgical strategy should therefore be seen as part of an overall strategy which encompasses other forms of treatment (e.g. intensive efforts to improve control of blood glucose level, blood pressure, and cholesterol level) in order to arrest the general progression of the disease and to reduce the risk of myocardial infarction and death.

Angioplasty, Balloon, Coronary↗
PubMed2003

INR self-management permits lower anticoagulation levels after mechanical heart valve replacement.

BACKGROUND: The Early Self Controlled Anticoagulation Trial (ESCAT I) showed that anticoagulation self-management after mechanical heart valve replacement decreased complication rates by maintaining INR levels closer to the target range than International Normalized Ratio (INR) home doctor management. The therapeutic range for the INR in that study was between 2.5 and 4.5 for all positions of prosthetic valves. ESCAT II should find out whether lowering the target range for INR self-management would further reduce complication rates. METHODS: ESCAT II is a prospective controlled randomized (valves: St. Jude Medical Standard or Medtronic Hall, treatment: conventional/low-dose) multicenter study with 3,300 patients. We present interim results of 1,818 patients. 908 were categorized as having a low-dose target range, which was INR 1.8 to 2.8 for prostheses in aortic position and 2.5 to 3.5 for prostheses in mitral position or in combined valve replacement. The control group (conventional group) with 910 patients aimed at an INR of 2.5 to 4.5 for all valve positions. RESULTS: In the conventional group, 74% of INR values measured were within the therapeutic range. In the low-dose group, 72% of the values were within that range. The linearized thromboembolism rate (% per patient year) was 0.21% for both groups. The bleeding complication rate was 0.56% in the low-dose regimen group versus 0.91% in the conventional group. CONCLUSIONS: Early onset INR self-management under oral anticoagulation after mechanical heart valve replacement enables patients to keep within a lower and smaller INR target range. The reduced anticoagulation level resulted in fewer grade III bleeding complications without increasing thromboembolic event rates.

Anticoagulants↗
PubMed2003

[Is age an independent predictor of mortality in cardiac surgery as postulated in EuroScore?].

The number of "older" patients undergoing cardiac surgery is steadily increasing. In the year 2000, 37% of all patients who underwent a cardiac operation in Germany were 70 years of age or older. Looking at data form our institution, we focused on the topic, whether age on its own is an independent determinant for mortality in cardiac surgery. Data from 8769 patients who underwent cardiac surgery in our institution from January 1996 until January 2002 were analyzed. For all patients, EuroScore and the corresponding age-stripped value was calculated. All recorded postoperative complications and 30-day mortality were statistically analyzed. EuroScore as well as the age-stripped EuroScore showed a significant rise with increasing age in the total number of patients as well as in the patients, who did not die during the first 30 days after the operation. The 30 day mortality and the incidence of postoperative complications increased significantly with age. While the EuroScore showed a significant age-dependent increase in patients who died within 30 days after the operation, the age-stripped EuroScore did not reveal a significant discrepancy in mortality with respect to age. Arterial hypertension, diabetes mellitus and atrial fibrillation, parameters not mentioned in EuroScore, showed significant differences among age groups. According to univariate analysis, arterial hypertension and diabetes mellitus were significant predictors of mortality. Entered into a multivariate logistic regression analysis, only diabetes mellitus achieved statistical significance. Our data and the known age-associated functional and structural changes of different organ systems show that age integrates risk factors together. In order to limit mortality in the steadily growing number of older and multi-morbid patients undergoing cardiac surgery, exceptional emphasis has to be put on patient selection and therapeutic measures to improve preoperative status.

Aged↗
PubMed2002

Is there any impact of the shape of aortic end-hole cannula on stroke occurrence? clinical evaluation of straight and bent-tip aortic cannulae.

OBJECTIVE: To compare the impact of straight and bent-tip aortic cannulae on stroke occurrence, location, and severity. METHODS: Prospective data were collected on 8,129 patients (coronary artery bypass grafting (CABG) and/or valvular surgery). 'Bent-tip' aortic cannulae were used in 15.6% of cases and 'straight' end-hole cannulae in 84.4% of cases. RESULTS: There were a total of 137 strokes: right anterior 52, left anterior 39, bilateral 23, posterior 18, and location not established 5. With the use of bent-tip cannulae, the incidence of strokes was 0.9% versus 1.8% with straight cannulae (chi2, p = 0.026). Bilateral and posterior strokes occurred more often with the use of straight cannulae (chi2, p = 0.015). Straight cannulae also related to the severity of strokes (chi2, p = 0.003). CONCLUSIONS: There is an influence of the type of cannula on the occurrence, location, and severity of strokes. Straight cannulae cause significantly more often and more severe bilateral and posterior strokes than bent-tip cannulae.

Aged↗
PubMed2001

[The impact of morbid obesity on the peri- and postoperative course after aortocoronary bypass surgery].

BACKGROUND AND OBJECTIVE: Excessive obesity is considered to be a risk factor in coronary bypass grafting. The aim of the current study was to examine if grossly overweight patients with a body mass index (BMI) > 35 suffer from higher morbidity and mortality when compared with patients with normal body weight (BMI = 20-25). PATIENTS AND METHODS: 206 extremely obese patients (group A) and 206 patients with normal body weight (group B) originating from a total of 5614 patients undergoing coronary bypass grafting in the time span between 1.4.1996-1.10.2000 were studied retrospectively and consecutively. The data were obtained from case histories, questionnaires and interviews. Statistical analysis was performed by the chi 2 test after Pearson, the t test and the Kaplan-Meier method depending on the statistical problem analysed using the SPSS software v. 8.0. RESULTS: The comparison of group A with group B revealed a significantly higher incidence of diabetes mellitus (p < 0.001), hypertension (p < 0.001) and hyperlipidaemia (p < 0.01) in group A. The only significant differences regarding the surgical procedure were the longer operation time (212.3 +/- 44.6 min, mean +/- SD) and aortic cross-clamp time (53.8 +/- 17.4 min, mean +/- SD) in group A (p < 0.05). The duration of mechanical ventilation, the incidence of respiratory insufficiency and the stay in the intensive care unit were not significantly different. The disorders of wound healing both in the sternal and the graft removal regions occurred significantly more frequently in group A (p < 0.001). The 30 days mortality rate in group A (1.5%) was not significantly different from group B (p < 0.001). The 30 days mortality rate in group A (1.5%) was not significantly different from group B (2.9%). The follow-up analysis of the 30 days mortality rate in different age groups revealed no significant differences in patients aged between 60 and 75 years. The mean survival rate after 4 years was 87.2% in group A and 86.4% in group B. CONCLUSION: In spite of higher morbidity our results did not reveal significantly higher mortality in extremely obese patients. After operation the patients considered their state improved, therefore elective coronary surgery in grossly overweight patients seems to be indicated also without previous weight reduction.

Adult↗
PubMed2001

[Short and long term results of aortic valve replacement in patients 80 years of age and older].

BACKGROUND: Due to demographic changes in average life expectancy the age of patients undergoing cardiac surgery is increasing as well. We have reviewed the short- and long-term outcome in patients over 80 years of age after aortic valve replacement with or without concomitant coronary grafting. PATIENTS AND METHOD: From 1.1.1995 until 31.12.1999, 126 patients (93 women, 33 men between 80 and 89 years, 82.8 +/- 2.4) underwent aortic valve replacement. 64 patients (group A) received isolated valve replacement, 62 (group B) underwent myocardial revascularization as well. RESULTS: The 30-day hospital mortality rate was 6.3% for group A and 14.5% for group B. The follow-up time ranged between 3 and 63 months (32 +/- 16). None of the patients had to be reoperated for prosthetic valve dysfunction or endocarditis. Bleeding complications due to anticoagulation therapy were observed by one patient from group A 3 years after the operation. Of the 15 deaths during the follow-up period seven (47%) were cardiac in nature and two (13%) related to stroke. Acturial survival rates for group A were 89%, 85% and 77% at 1, 2 and 3 years, and for group B 76%, 72% and 70%. Permanent nursing care was not required 1 year after the operation by 100% of patients in group A (2 years: 98%, 3 years 95%) and by 100% of patients in group B (2 years: 93%, 3 years: 90%). At an interval of 1 year after the operation 96% of patients in group A had not been hospitalized as a result of cardiac disorders (2 years: 96%, 3 years: 94%). The rates for group B were 88%, 81% and 75%. CONCLUSION: Compared with younger age groups, aortic valve replacement in patients 80 years of age and older is associated with a distinctly increased mortality and morbidity. However, our data suggest that considering the poor prognosis of conservative therapy of symptomatic aortic valve disease, functional status as well as life expectancy in this age group seem to be positively influenced by aortic valve replacement.

Actuarial Analysis↗
PubMed2001

Aortic valve replacement with or without concomitant coronary artery bypass grafting in the ninth decade of life.

Due to demographic changes in average life expectancy, the age of patients undergoing cardiac surgery is increasing. We have reviewed the short- and long-term outcome after aortic valve replacement with or without concomitant coronary artery bypass grafting in patients over 80 years of age. From 1 January 1995 until 30 June 1999, 114 patients (83 women and 31 men, 80-89 years of age, 82.8+/-2.4 years) with symptomatic aortic valve disease underwent aortic valve replacement. Of these patients, 54% (group A) received isolated valve replacement and 46% (group B) underwent myocardial revascularization as well. The perioperative mortality rate was 4.8% for group A and 7.7% for group B. The 30-day hospital mortality rate was 4.8% for group A and 15.4% for group B. The follow-up time ranged between 3 months and 63 months (32+/-15 months). None of the patients had to be reoperated for prosthetic valve dysfunction or endocarditis. Bleeding complications due to anticoagulation therapy were not observed. Of the 15 deaths during the follow-up period, seven (47%) were cardiac in nature and two (13%) were related to stroke. Actuarial survival rates for group A were 90%, 84%, and 76% at 1, 2, and 3 years, respectively, and for group B were 75%, 71%, and 68%. One year after the operation, permanent nursing care was not required by 100% of patients in group A (2 years, 98%; 3 years, 95%) and by 100% of patients in group B (2 years, 95%; 3 years, 91%). At a 1-year interval after the operation, 98% of patients in group A had not been hospitalized as a result of cardiac disorders (2 years, 98%; 3 years, 95%). The rates for group B were 90%, 85%, and 85%. Compared with younger age groups, aortic valve replacement in patients 80 years of age and older is associated with a distinctly increased mortality and morbidity. However, our data suggest that, considering the poor prognosis of conservative therapy of symptomatic aortic valve disease, functional status as well as life expectancy in this age group seem to be positively influenced by aortic valve replacement.

Actuarial Analysis↗
PubMed2001

Postoperative evaluation of radial artery grafts for coronary artery bypass grafting by transit-time Doppler flow measurements.

UNLABELLED: Due to the histological configuration of the vessel wall, the radial artery is prone to spasm as a result of handling or harvesting. Therefore, certain degrees of arterial wall spasm are unpreventable, even with appropriate pharmacologic treatment, while using the radial artery as a bypass graft in CABG. Consequently, the radial artery is only reluctantly used compared to saphenous vein grafts in CABG. In our clinical experience, the radial artery, if harvested carefully, has proved to be an excellent bypass graft. This investigation was undertaken to study the differences in blood flow measured directly after extracorporeal circulation in radial artery grafts and venous grafts. Both grafts were compared to the left internal mammarian artery anastomosed to the LAD. METHODS: Between January 1998 and December 1999, 198 patients who were undergoing coronary artery revascularization with two grafts were retrospectively investigated. In all patients, the left internal mammarian artery (LIMA) was anastomosed to the left anterior descending branch (LAD). For the second graft, either the saphenous vein or the radial artery was used. Proximal anstomoses were performed as end-to-side into the ascending aorta. Patients were divided into four groups: Group 1: n = 79 IMA-LAD, vein to the circumflex artery; Group 2: n = 56 IMA-LAD, vein to the right coronary artery; Group 3: n = 34; IMA-LAD, radial artery to the circumflex artery; Group 4: n = 29 IMA-LAD, radial artery to the right coronary artery. Graft-flow measurements were performed using the transit-time method after extracorporeal circulation was terminated. The mean systolic, diastolic, and mean blood flow were measured, and the pulsatility index was calculated. Statistical analysis was performed using the of t-test analysis between the variables mean blood flow and pulsatility index. A p-value of < 0.05 was defined as statistically significant. RESULTS: There were no statistically significant differences in mean blood flow or pulsatility index between radial artery and saphenous vein grafts to the right coronary artery and the circumflex artery, respectively. Also, there were no differences regarding vein grafts to the right coronary artery and to the circumflex artery, or regarding radial artery grafts to the two coronaries, respectively. In group 4, significantly lower blood flow to the LAD was found compared to group 1, and a significantly higher pulsatility index compared to groups 2 and 3. CONCLUSIONS: Radial artery grafts compared to saphenous vein grafts do not show significant differences early after operation in mean blood flow or pulsatility index. Further studies are needed to evaluate long-term performance of radial arteries as coronary bypass grafts and to compare the radial artery to the right mammarian artery and the standard saphenous vein graft.

Blood Flow Velocity↗
PubMed2001

Gadolinium-enhanced elliptically reordered three-dimensional MR angiography in the assessment of hand vascularization before radial artery harvest for coronary artery bypass grafting: first experience.

RATIONALE AND OBJECTIVES: To assess the suitability of contrast-enhanced magnetic resonance angiography (MRA) in the preoperative evaluation of hand vasculature in potential candidates for radial artery bypass grafting. METHODS: In 21 patients, gadobenate dimeglumine-enhanced, three-dimensional gradient-echo sequences of both hands were performed, as well as a Doppler ultrasound study with radial artery compression. Doppler findings were correlated with MRA, focusing on the assessment of anastomoses between the vascular bed of the ulnar and radial arteries. RESULTS: One individual had to be excluded because of accidentally disclosed metal foreign bodies. Sufficient depiction of the hand vasculature was achieved in the remainder. Seventeen patients had evidence of adequate collateral flow between the ulnar and radial artery supply on Doppler ultrasound. Three patients exhibited inadequate collateral flow, with angiographic signs of vessel occlusion or missing collaterals between the palmar arches. Two patients presented with stenosis or occlusion of the radial artery. Magnetic resonance angiograms displayed great variations in hand vasculature and collateral formation, with no mismatch compared with Doppler ultrasound results. CONCLUSIONS: Contrast-enhanced MRA displays vascularization of the hand in detail and supplies ultrasound flow measurements for radial artery harvest, with high-resolution angiographic data about possible vessel variations and the presence of anastomoses between the radial or ulnar artery supply.

Adult↗
PubMed2001

[Prophylaxis of bacterial endocarditis].

An effective prophylaxis against bacterial endocarditis is necessary in patients at risk. In all medical specialities, a lack of information about the importance concerning an antibiotic prophylaxis of bacterial endocarditis remains. Among other institutions the American Heart Association has updated recommendations for the prevention of bacterial endocarditis in order to more clearly define when prophylaxis is or is not recommended, improve practitioner and patient compliance, and reduce cost as well as potential side effects.

Adult↗
PubMed2001

[Mechanical versus biological heart valves].

Since the first successful heart valve replacement procedures were performed in the 1950s, a multitude of different heart valves have been developed and implanted. This review offers a structured overview of the most important mechanical and biological heart valves with special regard to the individual indications of mechanical versus biological heart valve replacement and to possible postoperative complications.

Adult↗