Harald Teufelsbauer

Endovascular Stent Grafting Versus Open Surgical Operation in Patients With Infrarenal Aortic Aneurysms

Background— Although transfemoral endovascular aneurysm management (TEAM) of infrarenal abdominal aortic aneurysms (AAA) is widely performed, open graft replacement is still considered the standard of care. The aim of this study was to investigate whether clear indications for TEAM can be established in patients with significant comorbidities without investigating differences in relative procedure efficacy or durability. Methods and Results— A propensity score–based analysis of 454 consecutive patients treated electively for AAA from January 1995 through December 2000 was performed. Of those 454 patients, 248 received open surgery and 206 received TEAM. In-hospital mortality rates (MRs) were compared. After adjusting for propensity scores, a Cox proportional hazard model (COX) was employed to test the influence of the respective treatment on postoperative 900-day survival estimates (SEs). Several potential preoperative risk factors were used as covariates. The MR of all patients was 3.7%. Explorative anal...

Hemostasis activation in patients with liver cirrhosis

In patients with liver cirrhosis a decrease of the coagulant potential is well-documented and has been linked to the high bleeding tendency among these patients. Whether the decrease of the coagulant potential is only due to a reduced hepatic synthesis of coagulation factors or also to its consumption by disseminated intravascular coagulation is debatable. We investigated hemostasis activation markers thrombin-antithrombin III complexes (TAT), fibrin degradation products (D-Dimer) and plasmin-alpha 2-antiplasmin complexes (PAP) in 41 outpatients with liver cirrhosis (Child-Pugh index 1 n = 18, 2 n = 15, 3 n = 8). Compared to controls similar in terms of age and sex, TAT, D-Dimer and PAP was elevated in the whole group of patients. A progressive increase of D-Dimer and PAP from Child 1 to 3 indicates a relationship between the severity of cirrhosis and the amount of hemostasis activation. Investigation of the natural anticoagulant potential showed significant decreases of antithrombin III (AT III), protein C, and protein S, most pronounced in Child 3 patients. Statistical analysis revealed significant negative correlations between levels of D-Dimer and both AT III and protein C, indicating that hemostasis activation is linked to the loss of anticoagulant potential.

Improved Survival After Abdominal Aortic Aneurysm Rupture by Offering Both Open and Endovascular Repair

BACKGROUND In the treatment of ruptured abdominal aortic aneurysm (rAAA), the results of open graft replacement (OGR) have remained constant but discouraging for the last 4 decades. Provided suitable anatomy, elective endovascular abdominal aortic aneurysm repair (EVAR) is less invasive and leads to improved perioperative mortality. Thus, it is reasonable to assume that endovascular treatment should improve the results of rAAA therapy. OBJECTIVE To determine whether the use of both endovascular and open repair of rAAA leads to improved results. DESIGN A single-center, retrospective analysis of 89 patients suffering from rAAA treated either by EVAR or OGR. PATIENTS From October 1999 until July 2006, a consecutive series of patients with rAAA were analyzed. Time was divided into 2 periods of 41 months. During the first period, 42 patients were treated by OGR exclusively. Period 2 started with the availability of an EVAR protocol to treat rAAA; 31 patients received open repair while 16 patients underwent EVAR. MAIN OUTCOME MEASURES Kaplan-Meier survival estimates were calculated and compared. RESULTS Survival estimates showed a statistically significant reduction in overall postoperative mortality following the introduction of EVAR (P < .03). The 90-day overall mortality rate was reduced from 54.8% to 27.7% during the second period (P < .01). Survival of patients older than 75.5 years was especially improved (75% vs 28.6%; P < .01). There was a parallel pattern of significant reduction of the mortality rate after OGR to 29% (P < .03). CONCLUSION Offering both EVAR and OGR to patients with rAAA leads to significant improvements in postoperative survival.

Endovascular treatment of a multimorbid patient with late AAA rupture after stent-graft placement: 1-year follow-up.

Purpose: To report successful endovascular management of a ruptured abdominal aortic aneurysm (AAA) in a multimorbid patient 40 months after primary stent-grafting. Case Report: A 64-year-old man presented with hypotension, severe back pain, and abdominal distension. Immediate computed tomography revealed a proximal type I endoleak due to distal migration of the stent-graft with subsequent rupture of the aneurysm. The patient was hemodynamically unstable, and open surgery was refused because of severe comorbidities that were the indications for initial endovascular repair. The diameter of the proximal aneurysm neck required the use of a thoracic stent-graft that was overly long, which led to occlusion of the contralateral stent-graft limb supplying not only the left leg but also a left kidney transplant. A crossover bypass was implanted to revascularize both. Conclusions: Minimally invasive strategies, even when challenged by complex vascular reconstructions, offer the possibility of managing ruptured aortic aneurysms in patients unsuitable for open surgery.

Effect of body armor on simulated landmine blasts to cadaveric legs.

BACKGROUND Antipersonnel landmine protective footwear relies on blast deflection or on exaggerated standoff between the foot and the explosive. Neither design has been tested for clinical effectiveness. METHODS 4 cadaveric lower extremities--3 fitted with a Koflach boot incorporating TABRE (Technology for Attenuating Blast Related Energy) were subjected to controlled blast with charges of up to 100 g trinitrotoluene (TNT). The blasts were recorded by a digital recording system. All legs were X-rayed and underwent computed tomography scanning before and after testing. RESULTS TABRE-protected limbs directly subjected to the blast hyperextended at the knee during firing. Injuries showed a pattern of open tibial fractures (Gustilo grade I, II), of multiple calcaneal (Sanders Type III, IV), and fibular fractures and of the tibial plateau, but showed no traumatic amputation. CONCLUSIONS Development of protective footwear against landmine blast is feasible. From medium mines up to charges of 100 g TNT limb salvage may be possible.

The impact of endovascular stent grafting on reducing mortality rates after surgical treatment of abdominal aortic aneurysms

OBJECTIVES to investigate whether appropriate selection in patients with infrarenal abdominal aortic aneurysms (AAA) for transfemoral endovascular aneurysm management (TEAM) or open graft replacement (OGR) may decrease in-hospital mortality rates (MR). DESIGN analysis of a clinical series over three periods in an university vascular center. Conclusions of the second period were drawn and prospectively applied in a third period and compared. METHODS during the period 1989-1994 only OGR was available (n=170). In the interval 1995-2000 either OGR or TEAM were carried out (n=454). During the period 01/2001-07/2002 the conclusions concerning selection of treatment modality were drawn and prospectively applied in 132 consecutive patients. MR were recorded and possible significant differences were checked. RESULTS during the first period MR was 6.5%. Overall MR decreased to 3.7% in the second interval. Overall MR of the last period was improved to 1.5% (p<0.05). No patient died after OGR (0% vs 6.5%, p<0.04). As all patients with significant individual risk profiles were treated by TEAM, MR slightly increased (2.9%), but the difference remained insignificant (2.4% in period 2). CONCLUSIONS risk adjusted selection of treatment modality influences the results after OGR significantly, thereby reducing overall MR of elective AAA treatment.

[Ruptured abdominal aortic aneurysms: status quo after a quarter century of treatment experience].

BACKGROUND Postoperative mortality rates between 40% and 50% have been invariably reported for the treatment of ruptured abdominal aortic aneurysms (rAAA) over the last 50 years. The aim of this analysis was to investigate which patient subgroups benefit from open surgery and in which subgroups a change of treatment strategies should be considered due to lack of improvement despite optimal patient management. PATIENTS AND METHODS From 1980 to 2002 a total of 230 patients underwent surgery because of a ruptured AAA. The observation period was divided into 3 intervals to achieve an approximately equal distribution of patients. The effect of the observation period and of baseline parameters on mortality rates were investigated. RESULTS Between 1980 and 1990, 72 patients were operated with a mortality rate of 38.9% (n = 28). During the second period (1991-1996) surgery was performed in 72 patients with a mortality rate of 40.3% (n = 29). In the third observation interval (1997-2002) 86 patients underwent surgery with an unvaried high mortality rate of 40.7% (n = 35). By applying a logistic regression model including age, gender, modality of rupture, location of cross-clamping and type of operation, only the modality of rupture and the patients age, which are uncontrollable by the surgeon, could be shown to have a significant impact. CONCLUSION Summing up these findings, open surgical repair of rAAA only leads to acceptable results when performed in younger patients without supposed comorbidities. Survival appears to be accidental in patients with advanced age and increased prevalence of relevant comorbidities/underlying diseases. Minimally invasive techniques may offer promising treatment options to those patients, as they do in elective interventions.SummaryBackgroundPostoperative mortality rates between 40% and 50% have been invariably reported for the treatment of ruptured abdominal aortic aneurysms (rAAA) over the last 50 years. The aim of this analysis was to investigate which patient subgroups benefit from open surgery and in which subgroups a change of treatment strategies should be considered due to lack of improvement despite optimal patient management.Patients and methodsFrom 1980 to 2002 a total of 230 patients underwent surgery because of a ruptured AAA. The observation period was divided into 3 intervals to achieve an approximately equal distribution of patients. The effect of the observation period and of baseline parameters on mortality rates were investigated.ResultsBetween 1980 and 1990, 72 patients were operated with a mortality rate of 38.9% (n=28). During the second period (1991–1996) surgery was performed in 72 patients with a mortality rate of 40.3% (n=29). In the third observation interval (1997–2002) 86 patients underwent surgery with an unvaried high mortality rate of 40.7% (n=35). By applying a logistic regression model including age, gender, modality of rupture, location of cross-clamping and type of operation, only the modality of rupture and the patient’s age, which are uncontrollable by the surgeon, could be shown to have a significant impactConclusionSumming up these findings, open surgical repair of rAAA only leads to acceptable results when performed in younger patients without supposed comorbidities. Survival appears to be accidental in patients with advanced age and increased prevalence of relevant comorbidities/underlying diseases. Minimally invasive techniques may offer promising treatment options to those patients, as they do in elective interventions.ZusammenfassungHintergrundBei der Behandlung des rupturierten abdominellen Aortenaneurysmas (rAAA) wurde während der letzten 50 Jahre eine nahezu unveränderte Mortalitätsrate zwischen 40% und 50% publiziert. Ziel dieser Analyse war es festzustellen, welche Patientensubgruppen von der offenen Operationstechnik profitieren und bei welchen trotz postulierter Optimierung im Management keine Verbesserung der Mortalitätsrate zu erzielen und damit eine Änderung der Behandlungsstrategie zu erwägen ist.Patienten und MethodenVon 1980 bis 2002 wurden 230 Patienten wegen eines rAAA operative behandelt. Der Beobachtungszeitraum wurde in 3 Intervalle mit annähernd gleichen Patientenzahlen unterteilt. Der Beobachtungszeitraum und grundlegende Basisparameter wurden bezüglich ihres Einflusses auf die Mortalitätsrate untersucht.ErgebnisseZwischen 1980 und 1990 wurden 72 Patienten operiert. Die Gesamt-Mortalitätsrate betrug 38,9% (n=28). Während der zweiten Periode (1991–1996) erfolgte eine operative Sanierung bei 72 Patienten mit einer Gesamt-Mortalitätsrate von 40,3% (n=29). Im dritten Beobachtungszeitraum (1997 bis 2002) wurde bei 86 Patienten eine Operation vorgenommen. Die Mortalitätsrate war mit 40,7% (n=35) unverändert hoch. In einem logistischen Regressionsmodell mit Einbeziehung von Alter, Geschlecht, Rupturmodalität, Klemmort und Operationsart ließ sich nur ein signifikanter Einfluss nicht beeinflussbarer Parameter wie Rupturmodalität und Patientenalter nachweisen.SchlussfolgerungZusammenfassend scheint die konventionelle offene chirurgische Versorgung beim rAAA nur bei jüngeren Patienten, ohne zu vermutende signifikante Begleiterkrankungne, zu vertretbaren ergebnissen zu führen. Bei Patienten im fortgeschrittenem Lebensalter mit entsprechend erhöhter Prävalenz von relevanten Begleit- oder Grunderkrankungen ergibt sich ein schicksalshafter Verlauf. Bei diesen Patienten könnte ein minimal invasives Verfahren ähnlich wie beim Elektiveingriff eine erfolgversprechende Behandlungsalternative eröffnen.

Beta 2-microglobulin. A reliable parameter for differentiating between graft rejection and severe infection after cardiac transplantation.

We investigated the role of beta 2-microglobulin as a noninvasive parameter to monitor acute rejection and severe infection in 45 consecutive heart transplant recipients. Endomyocardial biopsy revealed moderate (41 patients) or severe (three patients) rejection in 44 patients. Severe infections of bacterial septicemia (11 patients), bronchopneumonia (two patients), and viral infection (seven patients) were detected by a meticulous schedule of various clinical and laboratory tests. beta 2-Microglobulin levels in serum, generally corrected for serum creatinine, were significantly elevated in patients with infections (median, 6.3 mg/l; range Q10-Q90, 3.47-10.27 mg/l) compared with levels in patients with rejection (p less than 0.0001) or in patients in obviously good condition (p less than 0.0001). At the onset of acute rejection, the median corrected beta 2-microglobulin serum level was 1.56 mg/l (range Q10-Q90, -0.05-3.46 mg/l) and was significantly different from the control group (p less than 0.01). In addition, density function and empirical quantile analyses allowed us to define ranges of beta 2-microglobulin levels that would differentiate between rejection (2.05-3.46 mg/l) and infection (greater than 3.46 mg/l). With these values, sensitivity and specificity were 0.9 and 0.938 for detection of infection and 0.23 and 0.925 for detection of rejection, respectively. By means of beta 2-microglobulin, two cases of infection were misinterpreted as rejection (10%), and four of 44 rejections were mistaken for infections (9%). We conclude that measurements of beta 2-microglobulin may improve the management of heart transplant patients.

Repair of abdominal aortic aneurysms : The benefits of offering both endovascular and open surgical techniques

Two treatment options are available for abdominal aortic aneurysms (AAAs): open surgical technique with graft replacement and endovascular aortic aneurysm repair (EVAR) as a minimally invasive procedure. The intention of this review is to highlight the advantages of both procedures and to demonstrate that offering both procedures is beneficial for the patient when he or she makes the important decision regarding which treatment to select. A comparative evaluation of both treatment options is offered as well as a short description of the risk of rupture and its consequences. The authors discuss the latest literature as well as their own experiences. An innovative statistical approach-the propensity score-based Cox model-is presented to evaluate the 2 treatment options. The benefits of offering both EVAR and open surgery permit optimal management of AAA for the individual patient and tailor the treatment to his or her organ dysfunctions and impaired physical status. In addition, EVAR offers a treatment option for otherwise incurable high-risk patients.

Diagnostic Value of Hemostatic Parameters for Prediction of Complications in Patients Undergoing Aorto-Coronary Bypass Grafting

Though there has been rapid progress in coronary bypass surgery, postoperative hemostatic disorders due to extracorporeal circulation (ECC) are one of the remaining obstacles of this technique. Thrombocytopenia and platelet dysfunction [5], hyperfibrinolysis [3, 7] or activation of the anticoagulant system [4] going along with consumption of pro- and anticoagulant proteins [3–5] can cause extensive postoperative bleeding. Furthermore, the activation of intravasal coagulation might be the pathophysiological base for complex postoperative complications [4]. Thus, the aim of this study was to investigate whether a reduction in the preoperative thromboresistant potential quantified by various hemostatic parameters is linked to intra- or postoperative complications.