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Biomedical subjects

Ernst Wolner

Publications and source records attributed to Ernst Wolner.

At least 91 records · Page 5Linked to original sources
PubMed2003

Redo coronary artery bypass grafting with and without cardiopulmonary bypass in the elderly.

OBJECTIVES: Morbidity and mortality rates rise with increasing age in patients undergoing conventional redo coronary artery bypass grafting (CABG). The aim of this study was to compare our experience of minimal tissue dissection and target vessel revascularization without cardiopulmonary bypass (CPB) with the standard procedure of total dissection of the heart and complete revascularization with CPB for a population of elderly patients undergoing elective redo coronary artery CABG. METHODS: We retrospectively analyzed morbidity, mortality, and functional status of 47 patients older than 75 years who underwent redo CABG between January 1995 and June 2002. Thirty-one patients underwent redo CABG with CPB, and 16 patients underwent redo CABG without CPB. Follow-up end points were defined by patient survival, freedom from recurrence of angina (Canadian Cardiovascular Society [CCS] score), freedom from rehospitalizations and reinterventions, and the need for antianginal medication. RESULTS: There were 2 perioperative deaths (2 in the CPB group versus 0 in the group without CPB; P =.151). Nonfatal myocardial infarction occurred in 3 patients (3 in the CPB group versus 0 in the group without CPB; P =.082). Major adverse cardiac events occurred in 5 patients (5 in the CPB group versus 0 in the group without CPB; P =.058). At the time of follow-up, the mean CCS score of patients who underwent redo CABG with CPB was 1.5 +/- 0.8 and was 1.6 +/- 0.7 for patients who underwent redo CABG without CPB (P =.432). The rates of angina recurrence (16% with CPB versus 13.3% without CPB; P =.243), use of nitrates (8.7% with CPB versus 14.3% without CPB; P =.542), and survival (89% with CPB versus 93% without CPB; P =.238) were very comparable for the two groups. CONCLUSIONS: In this high-risk subgroup of patients, those patients who underwent target vessel revascularization without CPB showed a trend toward a lower rate of major adverse cardiac events, and this procedure seems promising with regard to long-term outcome. Therefore, target vessel revascularization may be offered liberally to elderly patients who are at high risk in surgeries involving complete revascularization with CPB. Further studies are needed to elucidate the long-term outcome of target vessel revascularization for elderly patients undergoing redo CABG.

Aged↗
PubMed2002

[National Health Care Plan for Austria: development and critical considerations].

Compared to health services in other countries in the world, the Austrian health care system works relatively well. At the moment it is shaped and dominated by various structures, decision makers and financial backers, which means that it does not work as well as it could under ideal circumstances. The government now wants to develop a national health care plan which, in a concerted action by all those involved in the health service, shall guarantee superior medical care while at the same time taking into account economic aspects. This paper takes a critical look at the idea of an Austrian health care plan from a clinical point of view.

Adult↗
PubMed2002

Optimizing ischemia/reperfusion in the failing rat heart--improved myocardial protection with acute ACE inhibition.

BACKGROUND: Whereas the number of patients with reduced left ventricular function after myocardial infarction who need revascularization is increasing, the operative outcome is still inadequate. Consequently, drugs that increase myocardial perfusion and decrease oxygen consumption of the remodeled myocardium are of particular interest to cardiac surgeons. Angiotensin-converting enzyme inhibitors (ACE-I) provide this pharmacologic profile. This study tests the hypothesis whether acute ACE inhibition during cardioplegic arrest improves outcome in failing rat hearts. METHODS AND RESULTS: Male Wistar rats (260+/-15 g) underwent coronary ligation. Ten weeks later the rats had developed heart failure (HF). Hearts were harvested and studied on a red cell-perfused working heart: 60 minutes of ischemia, protected by cold blood cardioplegia (CP) every 20 minutes, and 45 minutes of reperfusion. Rats were randomly assigned to 2 groups, 1 group receiving the ACE-I quinaprilat with CP (QuinaMI, n=11), and 1 group receiving CP only (MI, n=8). Hemodynamic recovery, high-energy phosphates (HEP), and morphometry were analyzed. Groups showed similar degrees of myocardial infarction (44+/-5 versus 39+/-4% of LVmass), LVEDP (5.0+/-1 versus 4+/-1 mm Hg) and no differences in baseline values such as external heart work (EHW) and coronary flow (CF). At the end of reperfusion, EHW and CF were significantly higher in QuinaMI than MI (P<0.05 and 0.01), LVEDP had returned to baseline in QuinaMI (P<0.01). HEP were significantly higher preserved in QuinaMI than MI (P<0.05). CONCLUSIONS: Acute ACE inhibition during CP improves postischemic systolic and diastolic function, coronary perfusion as well as HEP-levels in a rat model of HF. These results may have clinical impact on patients with HF undergoing cardiac surgery.

Adenine Nucleotides↗
PubMed2002

Prosthetic replacement of the aorta is a risk factor for aortic root aneurysm development.

BACKGROUND: Noncompliant prostheses are used in aortic replacement. We hypothesized that this leads to increased distension and wall stress in the aortic root because of the loss of ventriculo arterial coupling. METHODS: Pressure relations in the aortic root caused by changes of aortic elasticity simulating prosthetic aortic replacement were tested in a computer model. We then developed an in vitro model using porcine aortas and performed in vivo validation. RESULTS: Findings in vitro and in vivo confirmed the predicted changes of the computer model. Pressure amplitude increased significantly by 17% after prosthetic replacement (p < 0.01). Pressure-time differential (Dp/dt) and dicrotic notch pressure amplitude both increased significantly. Echocardiography demonstrated systolic aortic root distension with percentage area change increasing in vitro from 28.2%+/-9.7% to 35.9%+/-10% (p < 0.05) and in vivo from 13.3%+/-3.1% to 24.3%+/-3.1% (p < 0.0001). Aortic root wall stress increased markedly. CONCLUSIONS: Replacement of the aorta with vascular prostheses causes important negative alterations of hemodynamics and increases in wall stress.

Animals↗
PubMed2002

Surgical treatment of acute type A dissection: is rupture a risk factor?

BACKGROUND: The purpose of this study was to evaluate the significance of aortic rupture on clinical outcome in patients after aortic repair for acute type A dissection. METHODS: One hundred and twenty patients underwent aortic operations with resection of the intimal tear and open distal anastomosis. Median age was 60 years (range 16 to 87); 78 were male. Thirty-six patients had only ascending aortic replacement, 82 had hemiarch repair, and 2 had the entire arch replaced. Retrograde cerebral perfusion was utilized in 66 patients (53%). Rupture defined as free blood in the pericardial space was present in 60 patients (50%). Univariate and multivariate analyses were performed to assess the risk factors for mortality and neurologic dysfunction. RESULTS: Overall hospital mortality rate was 24.2% +/- 4.0% (+/- 70% confidence level) but did not differ between patients with aortic rupture or without (p = 0.83). The incidence of permanent neurologic dysfunction was 9.4% overall, 10.5% with rupture and 8.3% without rupture (p = 0.75). Multivariate analysis revealed absence of retrograde cerebral perfusion and any postoperative complication as statistically significant indicators for in-hospital mortality (p < 0.05). Overall 1- and 5-year survival was 85.3% and 33.7%; among discharged patients, survival in the nonruptured group was 89% and 37%, versus 81% and 31% in the ruptured group (p = 0.01). CONCLUSIONS: Aortic rupture at the time of surgery does not increase the risk of hospital mortality or permanent neurologic complications in patients with acute type A dissections. However, aortic rupture at the time of surgery does influence long-term survival.

Acute Disease↗
PubMed2002

Cognitive deficit after aortic valve replacement.

BACKGROUND: Impairment of cognitive brain function after coronary artery bypass grafting (CABG) is well known. In contrast the potential neurocognitive damage related to aortic valve replacement (AVR) is uncertain. METHODS: In this contemporary case-matched control study we followed 30 patients (mean age 70 years) receiving isolated AVR with a biological prosthesis. A cohort of sex-and age-matched patients (n = 30, mean age 70 years) receiving CABG with cardiopulmonary bypass served as controls. Cognitive brain function was measured by means of auditory evoked P300 potentials (peak latencies, ms) before the operation and 7 days and 4 months after the operation. Additionally, two standard psychometric tests (Mini-Mental State Examination and the Trailmaking Test A) were performed. RESULTS: In preoperative measures there was no difference between patients undergoing AVR and patients undergoing CABG (AVR 378 +/- 37 ms, CABG 374 +/- 32 ms, p = 0.629). One week after surgery P300 peak latencies were prolonged (impaired) in both groups compared with preoperative values (AVR 405 +/- 43 ms, p = 0.001; CABG 398 +/- 44 ms, p = 0.004). At this point of follow-up there was no difference between the groups (p = 0.607). Finally, 4 months after surgery P300 auditory evoked potentials returned to normal in the CABG group (380 +/- 24 ms, p = 0.940) while in contrast in the valve group they continued to become prolonged (worsened) compared with preoperative values (410 +/- 47 ms, p = 0.005). At this time of follow-up P300 peak latencies were prolonged in AVR patients as compared with CABG patients (p = 0.032). The Trailmaking Test A and Mini-Mental State Examination failed to discriminate any difference. CONCLUSIONS: Four-month impairment of cognitive brain function is more pronounced in patients undergoing biological AVR as compared with age-matched control patients undergoing CABG. Further studies are needed to clarify the potential pathologic mechanisms causing an ongoing cognitive impairment in patients with biological aortic valve prostheses.

Aged↗
PubMed2002

Combined surgical and endovascular treatment of acute aortic dissection type A: preliminary results.

BACKGROUND: The established treatment modality of acute Stanford type A dissection includes repair of the ascending aorta and various portions of the aortic arch, whereas the descending aorta is left untreated. We report a simultaneous approach of open repair of the ascending aorta with transluminal stent grafting of the descending aorta to minimize the consequences of an untreated descending aorta. METHODS: From April 2001 to February 2002, 8 consecutive patients (3 women [37.5%] and 5 men [62.5%]) with a mean age of 55.7 years (range, 45 to 70 years) were intended to be treated with the combined method of surgical repair of the ascending aorta and transluminal stent grafting into the descending aorta during the period of deep hypothermic circulatory arrest. Circulatory arrest time ranged between 30 and 67 minutes (average, 38.8 minutes). Specially designed Talent stent grafts (32 to 40 mm in diameter, length 13 cm) were inserted under direct vision and deployed with the proximal end at the origin of the left subclavian artery. RESULTS: Intraoperative stent graft placement was successful in 7 patients (87.5%). Because of severe kinking of the distal arch, stent insertion failed in 1 patient (12.5%). One patient with a history of preoperative stroke in the middle cerebral artery died because of intracerebral bleeding on postoperative day 2, resulting in an in-hospital mortality of 12.5%. Mean intensive care unit stay was 6.4 days (range, 2 to 21 days) and overall hospital stay was 18.2 days (range, 7 to 33 days). Completion computed tomographic scans revealed complete thrombosis of the false lumen in 2 patients and partial thrombosis in 4 patients. Follow-up was complete and ranged from 1 to 9 months (mean, 5.4 months). CONCLUSIONS: This preliminary study shows that combined surgical and endovascular treatment of acute type A dissection is feasible, and at least partial thrombosis of the false lumen can be achieved, potentially minimizing the risk of further dilatation or rupture. Additionally, the stent graft expands the otherwise sickle-shaped true lumen, thereby ameliorating distal aortic perfusion. Long-term results are warranted to demonstrate the effectiveness of this new combined treatment modality.

Acute Disease↗
PubMed2002

The vacuum-assisted closure system for the treatment of deep sternal wound infections after cardiac surgery.

BACKGROUND: The VAC system (vacuum-assisted wound closure) is a noninvasive active therapy to promote healing in difficult wounds that fail to respond to established treatment modalities. The system is based on the application of negative pressure by controlled suction to the wound surface. The method was introduced into clinical practice in 1996. Since then, numerous studies proved the effectiveness of the VAC System on microcirculation and the promotion of granulation tissue proliferation. METHODS: Eleven patients (5 men, 6 women) with a median age of 64.4 years (range 50 to 78 years) with sternal wound infection after cardiac surgery (coronary artery bypass grafting = 5, aortic valve replacement = 5, ascending aortic replacement = 1) were fitted with the VAC system by the time of initial surgical debridement. RESULTS: Complete healing was achieved in all patients. The VAC system was removed after a mean of 9.3 days (range 4 to 15 days), when systemic signs of infection resolved and quantitative cultures were negative. In 6 patients (54.5%), the VAC system was used as a bridge to reconstructive surgery with a pectoralis muscle flap, and in the remaining 5 patients (45.5%), primary wound closure could be achieved. Intensive care unit stay ranged from 1 to 4 days (median 1 day). Duration of hospital stay varied from 13 to 45 days (median 30 days). In-hospital mortality was 0%, and 30-day survival was 100%. CONCLUSIONS: The VAC system can be considered as an effective and safe adjunct to conventional and established treatment modalities for the therapy of sternal wound infections after cardiac surgery.

Aged↗
PubMed2002

The On-X prosthetic heart valve at five years.

BACKGROUND: Multicenter clinical trials were conducted in Europe and North America to evaluate the performance of the On-X bileaflet heart valve prosthesis (Medical Carbon Research Institute, Austin, TX). METHODS: A total of 532 patients underwent implantation, 303 for aortic valve replacement (AVR) and 229 for mitral valve replacement (MVR), at 20 centers from September 1996 to July 2001. The study followed the guidelines of the AATS/STS. Mean follow-up was 23 months (total 1024 patient-years; maximum 5 years). Poolability analysis was performed to show the equivalence of the populations. RESULTS: Patients and results were found to be similar and poolable. Freedom from adverse events at 2 years in the study were as follows: thromboembolism, 96.0% for AVR patients and 96.3% for MVR; thrombosis, 100% for AVR and 100% for MVR; bleeding events, 96.6% for AVR and 95.7% for MVR; and overall mortality, 95.2% for AVR and 92.4% for MVR. Median lactate dehydrogenate levels were in the normal range for AVR and MVR patients at all intervals. At 1 year, AVR echocardiographic results for the 19 to 25 valves, respectively, ranged from 1.5 to 2.8 cm2 for effective orifice area and 9.2 to 4.7 mm Hg for mean gradient, and MVR effective orifice area by pressure half-time was 2.8 cm2 and mean gradient was 4.2 mm Hg. CONCLUSIONS: The two trials have given similarly excellent results for the On-X valve.

Adult↗
PubMed2002

Dilatation of the autograft root after the Ross operation.

OBJECTIVE: Structural differences of the pulmonary root may predispose it to progressive dilatation in the systemic circulation after the Ross operation. We identified the incidence and risk factors of pulmonary autograft root dilatation. METHODS: One hundred and seven adult patients (mean age of 36+/-11 years) were followed after the Ross operation since 1991 including an echocardiogram within 3 months of surgery and yearly clinical assessment and echocardiography. The autograft was measured at the maximum diameter of the sinus (SV) and aortic insufficiency (AI) assessed. A SV of >37 mm was considered as root dilatation and the incidence over time was calculated using the Kaplan-Meier method. Clinically relevant dilatation was defined as a root diameter of >42 mm. In addition, we determined the percentage change of the sinus diameter between the early and latest echocardiogram. Furthermore we tested the influence of patient variables and risk factors on dilatation. RESULTS: By 1 year, dilatation was found in 21 patients (20%). The SV was >42 mm in eight patients (7%). By 7 years, only 45% of patients were free of dilatation. Eleven patients (10%) had a SV of >42 mm. Increase in SV was time related and linear. However, 90% of patients showed <25% dilatation during follow-up. Time from operation, early SV diameter, male gender and surgical technique were identified as significant risk factors of dilatation. However, dilatation has not lead to reoperation due to aneurysm formation or development of significant AI. CONCLUSIONS: We conclude that time dependent autograft root dilation occurs but does not cause an increase in AI and need for reoperation up to 7 years. These findings warrant the pursuit of the concept of the Ross operation in young patients who regain excellent functional status and life style without anticoagulation.

Adult↗
PubMed2002

Successful lung volume reduction surgery brings patients into better condition for later lung transplantation.

OBJECTIVES: Lung volume reduction surgery (LVRS) is accepted as a potential alternative therapy to lung transplantation (LTX) for selected patients. However, the possible impact of LVRS on a subsequent LTX has not been clearly elucidated so far. We therefore analyzed the course of 27 patients who underwent LVRS followed by LTX in our institution. METHODS: Twenty-seven patients (11 male, 16 female, mean age 51.9+/-2.2 years) out of 119 patients who underwent LVRS between 1994 and 1999 underwent LTX 29.7+/-3.2 months (range 2-57 months) after LVRS. Based on the postoperative course of FeV1 after LVRS (best value within the first 6 months postoperatively compared with the preoperative value) patients were divided into two groups: Group A (n=11) without any improvement (FeV1 <20% increase), and Group B (n=16) with FeV1 increase > or = 20% after successful LVRS which declined to preoperative values after 8-42 months. Subsequent LTX was performed 22.9+/-5.6 months after LVRS in Group A and 34.3+/-4.9 months after LVRS in Group B (P<0.05). Patients were analyzed according to the course of their functional improvement and of their body mass index (BMI) after LVRS and to survival after LTX, respectively. Values are given as the mean+/-SEM and significance was calculated by the chi(2)-test whereas continuous values were estimated by Student's t-test. RESULTS: Patients in Group A without improvement in FeV1 after LVRS had no increase in BMI as well and this resulted in a high perioperative mortality of 27.3% after LTX. On the contrary, patients in Group B, who had a clear increase of FeV1 after LVRS, experienced a significant increase of BMI of 23.2+/-4.5% as well (P<0.05). This improvement in BMI remained stable despite a later deterioration of FeV1 prior to LTX. After LTX, these patients had a significantly lower perioperative mortality of 6.3% as compared to Group A (P=0.03). CONCLUSIONS: Successful LVRS delays the need for transplantation, improves nutritional status and brings patients into a better pretransplant condition, which results in decreased perioperative mortality at LTX. Patients after failed LVRS, however, should be considered as poor candidates for later transplantation.

Body Mass Index↗
PubMed2002

Quinaprilat during cardioplegic arrest in the rabbit to prevent ischemia-reperfusion injury.

OBJECTIVES: This study evaluated intracardiac angiotensin-converting enzyme inhibition as an adjuvant to cardioplegia and examined its effects on hemodynamic, metabolic, and ultrastructural postischemic outcomes. METHODS: The experiments were performed with an isolated, erythrocyte-perfused, rabbit working-heart model. The hearts excised from 29 adult New Zealand White rabbits (2950 +/- 200 g) were randomly assigned to four groups. Two groups received quinaprilat (1 microg/mL), initiated either with cardioplegia (n = 7) or during reperfusion (n = 7). The third group received l-arginine (2 mmol/L) initiated with cardioplegia (n = 7). Eight hearts served as a control group. Forty minutes of preischemic perfusion were followed by 60 minutes of hypothermic arrest and 40 minutes of reperfusion. RESULTS: All treatments substantially improved postischemic recovery of external heart work (62% +/- 6%, 69% +/- 3%, and 64% +/- 5% in quinaprilat during cardioplegia, quinaprilat during reperfusion, and l-arginine groups, respectively, vs 35% +/- 5% in control group, P <.001) with similarly increased external stroke work and cardiac output. When administered during ischemia, quinaprilat significantly improved recovery of coronary flow (70% +/- 8%, P =.028 vs quinaprilat during reperfusion [49% +/- 5%] and P =.023 vs control [48% +/- 6%]). l-Arginine (55% +/- 7%) showed no significant effect. Postischemic myocardial oxygen consumption remained low in treatment groups (4.6 +/- 1.2 mL. min(-1). 100 g(-1), 6.0 +/- 2.2 mL. min(-1). 100 g(-1), and 4.7 +/- 1.6 mL. min(-1). 100 g(-1) in quinaprilat during cardioplegia, quinaprilat during reperfusion, and l-arginine groups, respectively, vs 4.2 +/- 0.8 mL. min(-1). 100 g(-1) in control group), even though cardiac work was markedly increased. High-energy phosphates, which were consistently elevated in all treatment groups, showed a significant increase in adenosine triphosphate with quinaprilat during ischemia (2.24 +/- 0.14 micromol/g vs 1.81 +/- 0.12 micromol/g in control group, P =.040). Ultrastructural grading of mitochondrial damage revealed best preservation with quinaprilat during ischemia (100% [no damage], P =.001 vs control). CONCLUSION: These experimental findings have clinical relevance regarding prevention of postoperative myocardial stunning and low coronary reflow in patients undergoing heart surgery.

Analysis of Variance↗
PubMed2002

Loss of pRb2/p130 expression is associated with unfavorable clinical outcome in lung cancer.

Altered expression of cell cycle regulators represents a frequent event in both small cell and non-small cell lung cancer (NSCLC). Despite several studies that reported involvement of tumor suppressor genes, such as p53 and pRb, in the development and progression of lung cancer, contrasting opinions exist about the prognostic role of this protein in this neoplasm. We developed an immunohistochemical assay suitable for the detection of pRb2/p130, the last discovered member of the retinoblastoma gene family, on formalin-fixed and paraffin-embedded sections. We evaluated the immunohistochemical expression of pRb2/p130 in 135 lung cancer specimens, and performed Western blot analysis in a subset of 30 corresponding tumor lysates. A high correlation between immunohistochemical data and Western blot results (P = 0.0004) was found. We statistically analyzed the relationship between overall survival (OS) time and pRb2/p130 expression according to the different histological types in 105 patients. We did not find any correlation between pRb2/p130 expression and OS in small cell lung cancers, whereas in NSCLCs a direct relationship between pRb2 and OS was found in both adenocarcinoma (P = 0.0002) and squamous cell carcinoma (P = 0.0002) histotypes. According to univariate analysis, pRb2/p130 was a prognostic factor of which the lost or reduced expression correlated with a shorter OS (P < 0.0000). At multivariate analysis, pRb2/p130 expression was an independent predictor of OS (P = 0.0001) when considered together with histotype. This study demonstrates for the first time the potential independent prognostic value of pRb2/p130 expression on formalin-fixed, paraffin-embedded sections from lung cancer patients. pRb2/p130 immunoreactivity can be used to predict OS in patients with NSCLC and, therefore, may represent a new prognostic marker.

Blotting, Western↗
PubMed2002

The University of Vienna experience in heart transplantation.

Since the University of Vienna Cardiac Transplant Program began in 1984, 892 heart transplant procedures have been performed through the end of 2001. One- and five-year survival has increased steadily over time to 80% and 75%, respectively, in the most recent cohort. Ten-year survival is 55%. Over the past 10 years our program has seen dramatic changes in patient selection, accepting now patients with more risk factors (age, diabetes, elevated pulmonary resistance,..). Developments in immunosuppression have decreased the incidence of infection, rejection and graft arteriosclerosis continuously. Our program continues to pursue novel strategies to improve the survival and quality of life of our heart transplant patients.

Adolescent↗
PubMed1990

[The determination of trace amounts of protein in solutions containing surface-active substances].

A rapid and sensitive method for protein determination (0.5-16 micrograms) in samples of any volume containing various surfactants in concentration up to 1% is suggested. The method includes the protein acid denaturation, the solution of acid insoluble precipitate of detergent in ethanol (25-30%), the protein determination on nitrocellulose filter, dyeing by aminoblack 10 B, elution of dyed complex and colorimetric determination at 630 nm.

Amido Black↗
PubMedDate not supplied

Establishment of vessel-like structures in long-term three-dimensional tissue culture of myocardium: an electron microscopy study.

To assess whether long-term three-dimensional (3D) tissue culture of myocardium enables the in vitro establishment of vessel-like structures, myocardial tissue from newborn mice was incubated under conditions of 3D culture for at least 3 weeks, and studied by phase-contrast microscopy, conventional histology, immunohistochemistry, and electron microscopy. During 3 weeks of culture, a mean 24.35 +/- 3.74% of all aggregates contracted spontaneously. The contracting aggregates displayed a tissue-like architecture with small basal and apical zones, and a large central zone. The basal and apical zone consisted of immature mesenchymal cells. The underlying shell of the aggregate contained many cardiomyocytes. Vessel-like structures were found concentrated within the aggregates. Immunohistochemistry showed that up to 15% of the cells in the central zone of the aggregate were positive for the endothelial-specific BS-I lectin. Vessel-like structures were formed by cells, which often showed intracytoplasmatic lumena. Surrounding the neocapillaries, structures of a rudimentary basal membrane could be detected. A 3D culture of myocardial tissue permits the establishment of a rudimentary capillary network within the tissue aggregates, which presumably guarantees a sufficient tissue perfusion up to a maximum aggregate diameter of approximately 900 microm.

Adaptation, Physiological↗
PubMedDate not supplied

Extensive coagulation monitoring in patients after implantation of the MicroMed Debakey continuous flow axial pump.

Ventricular assist device (VAD) implantation is associated with impaired primary hemostasis and thromboembolic complications. Recently, a new generation of implantable continuous flow axial pumps was introduced into clinical application. To study the potential thrombogenic properties of this type of pump, we applied extensive platelet monitoring was applied. In our institution, 13 patients received the MicroMed DeBakey VAD as a bridge to transplantation. Routine coagulation tests (platelet count, activated partial thromboplastin time, prothrombin time, antithrombin III activity) and platelet function tests (whole blood aggregometry, thrombelastography, flow cytometry) were performed. No clinically relevant thromboembolic events were detected. No correlation was found between global function tests, platelet aggregation, and thrombelastography. No correlation was detected between platelet activation and hemolysis parameters. Platelet aggregation and coagulation index were significantly suppressed early after operation. A subsequent phase of hyper-aggregability, starting around day 6, suggested the initiation of antiaggregation therapy. Platelet activation markers were upregulated in the postoperative period but were returned to preoperative levels after initiation of aspirin. In contrast to routine coagulation monitoring, platelet function tests reflect in detail the coagulation status of blood pump recipients and the efficiency of antiaggregation therapy. Aspirin and dipyridamole therapy in addition to oral anticoagulation using phenprocoumon may contribute to platelet function and clot mechanics restoration and is, therefore, recommended for patients after VAD implantation.

Adolescent↗