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T Wahlers

Publications and source records attributed to T Wahlers.

At least 19 recordsLinked to original sources
PubMed2006

Antegrade selective cerebral perfusion--how to proceed?

Aortic surgery still carries a high risk of brain damage that dominates postoperative morbidity and mortality. The concept and advantages of antegrade selective cerebral perfusion, which allows for numerous variations in its implementation, have been clearly seen for more than a decade now, but the preferred way of positioning remains unanswered. Ideal perfusion during ascending aorta/arch surgery should allow the easy implementation of selective antegrade cerebral perfusion while avoiding atheroembolization or false lumen perfusion during dissections.

Aortic Diseases↗
PubMed2006

The controversy of donor serum sodium levels in heart transplantation--a multicenter experience.

BACKGROUND: Elevated donor serum sodium is a phenomenon often encountered in the management of brain dead donors. The clinical relevance on recipient outcome is less examined. We investigated the impact of elevated donor serum sodium levels (DSL) on outcome after heart transplantation in 1800 heart transplantations. METHODS: Data was conducted in a retrospective analysis from 1989 until 2005. The transplantations were performed at three German heart transplant centers. The joined database included DSL at the time of organ procurement, recipient and donor age, ischemia time, primary graft failure and survival data. RESULTS: Mean DSL was 147.7 +/- 10.3 l/l (range 111 - 208 l/l). Recipients were divided into 4 groups with percentiles of 141, 147, and 154 l/l resulting in DSL of A: 135.8 +/- 4.4, B: 143.6 +/- 1.7, C: 149.7 +/- 1.9, and D: 161.3 +/- 7.7 l/l for the four quartiles. Primary graft failure occurred in 2.6 % of the patients with A: 2.8 %, B: 2.8 %, C: 3.7% and D: 1.4 % ( P = n.s.). Mean 5- and 10-year-survival rates were 70.9 % (57.6 %) with A: 71.1 % (53.86 %), B: 69.3 % (53.9 %), C: 72.7 % (61.0 %), D: 71.2 % (62.4 %), respectively ( P = n. s.). In a multivariate analysis a significant impact on postoperative results could be revealed for recipient age ( P = 0.002), ischemia time ( P = 0.002) and donor age ( P = 0.009). DSL were no individual risk factor in the multivariate analysis. CONCLUSION: There was no impact of donor serum sodium levels neither on early postoperative results, nor on long-term outcome indicating that cardiac allografts from donors with elevated sodium levels might be transplanted successfully, achieving favourable results.

Adolescent↗
PubMed2005

Transcriptomic and proteomic patterns of systemic inflammation in on-pump and off-pump coronary artery bypass grafting.

BACKGROUND: Coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB) provides controlled operative conditions but induces a whole-body inflammatory response capable of initiating devastating morbidity and mortality. Although technically more demanding, deliberate avoidance of CPB in off-pump surgery attenuates the physiological insult associated with CABG. METHODS AND RESULTS: To systematically assess the molecular mechanisms underlying the better-preserved remote organ function, we studied gene expression patterns in leukocytes and plasma proteomic response to on-pump and off-pump CABG. Proteomic analysis confirmed (tumor necrosis factor-alpha, interleukin [IL]-6, IL-10) and expanded (eg, interferon [IFN]-gamma, granulocyte colony-stimulating factor [G-CSF], monocyte chemotactic protein-1, macrophage inflammatory protein-1beta) the mediators released on CPB, whereas blood leukocyte transcriptomics suggested that circulating leukocytes are not primarily responsible for this response. Interestingly, release of some cytokines (eg, IL-6, IFN-gamma, G-CSF) was observed on off-pump surgery to a similar extent but with delayed kinetics. A total of 45 of 4868 transcripts were identified to be significantly altered as a result of initiation of CPB. Systematic analysis of transcriptional activation by CPB revealed primarily genes involved in inflammation-related cell-cell communication (such as L-selectin or intercellular adhesion molecule-2) and signaling (such as IL-1, IL-8, or IL-18 receptors and toll-like receptors 4, 5, and 6), thus confirming a "primed" phenotype of circulating peripheral blood mononuclear cells. CONCLUSIONS: Gene array and multiplex protein analysis, only in concert, can illuminate the molecular mechanisms responsible for systemic sequelae of CPB and indicate that circulating leukocytes overexpress adhesion and signaling factors after contact with CPB, which potentially facilitates their trapping, eg, in the lungs and may promote a subsequent tissue-associated inflammatory response.

Animals↗
PubMed2005

[Aortic valve replacement in elderly patients].

Aortic valve procedures represent the second most frequent surgical intervention in cardiac surgery. Due to the demographic developments there is a shift into the seventh to ninth decade of age. For patients beyond 65 years biological valve prostheses are recommended. In these patients xenografts are showing only a slow degeneration. Furthermore, especially these patients are threatened by complications caused by cumarine therapy. Modern valve-sparing procedures might also be used in old patients with an insurable risk. Mortality is slightly increased in old patients compared to younger patients. However, additional risk factors like clinical stage as well as co-morbidity affect the mortality significantly. The specific operative procedure has to select with respect to the individual situation of the patient. In conclusion, aortic valve surgery should be taken into account also in older, symptomatic patients.

Aged↗
PubMed2005

Healing characteristics of a new silver-coated, gelatine impregnated vascular prosthesis in the porcine model.

OBJECTIVES: To investigate the intraluminal and extraluminal healing behaviour of a new metallic silver coated, gelatine impregnated vascular graft. DESIGN: Comparative animal experimental investigation with randomisation of the animals to control and experimental groups. MATERIAL AND METHODS: 24 pigs were assigned to two control and two experimental groups. The prostheses were interposed in the pigs' infrarenal aorta. For the evaluation, macroscopic, histological and immunohistochemical criteria were applied. RESULTS: The macroscopic evaluation after explantation of the prosthesis revealed similar healing characteristics in the control and experimental groups. The microscopic determination of neo-intimal thickness showed no significant differences between the groups; nor did the immunohistochemical investigations show any significant difference between the control group and the silver-coated prosthesis group. CONCLUSIONS: No disadvantage of the silver coating in terms of healing and graft patency was found. A possible advantage in terms of the antibacterial effect of the silver coating must be investigated in the clinical setting.

Animals↗
PubMed2005

Selective cerebral perfusion via right axillary artery direct cannulation for aortic arch surgery.

BACKGROUND: The risk of neurological complications is still a life-threatening event for patients undergoing proximal aortic arch or total aortic arch surgery. To prevent these complications, axillary artery cannulation and antegrade selective cerebral perfusion were utilized. We compared the effects of using hypothermic circulatory arrest (HCA) alone or with selective cerebral perfusion (SCP/AX) via right side axillary artery direct cannulation. METHODS: 120 patients, mean age 61 +/- 12 years (range 26 - 80), underwent proximal aortic or total aortic arch replacement between 1999 and 2004; 46 were female. We retrospectively compared the results of the two patient groups comparable for preoperative risk factors: 71 pts were operated using HCA beginning in 1999 and 49 pts using HCA/SCP via axillary artery direct cannulation since 2002. The indication for surgery was an aortic aneurysm in 80 (67 %) patients and aortic dissection in 36 (30 %) patients. The groups were well matched with regard to median age (60 vs. 62 yrs), urgency (emergent/urgent 36 vs. 44 %; elective 64 vs. 65 %), and several other known risk factors ( p = ns). RESULTS: Overall in-hospital mortality was 13 %: 10 % with HCA vs. 6 % with SCP/AX. Permanent neurological dysfunction occurred in 10 % with HCA vs. 6 % with SCP/AX. Transient neurological dysfunction (TND) in patients surviving without stroke was lower with SCP/AX (10 %) than with HCA (17 %) ( p = ns). Mean duration of HCA was 28 +/- 12 min when isolated HCA was used, and significantly shorter with 21 +/- 6 min when the combination of SCP/AX ( p = 0.03) was used. Mean duration of CPB was 202 +/- 55 min with HCA vs. 192 +/- 50 min with SCP/AX ( p = ns). Comparison of the groups who had comparable preoperative risk factors showed a trend towards lower in-hospital mortality, stroke and TND rates, a significant reduction in cardiac ( p = 0.034), infectious ( p = 0.025) and bleeding complications ( p = 0.04) in SCP/AX compared with HCA, as well as a significantly shorter duration of hospitalization ( p = 0.046) and shorter ICU stay ( p = ns). CONCLUSION: Our results suggest that HCA/SCP is superior to HCA alone for preventing cerebral injury during operations on the aortic arch. By reducing embolic risk, as well as the duration of HCA, SCP with axillary artery direct cannulation may be the optimal technique for averting cerebral events, reducing complications, and shortening hospital stays following aortic arch repair.

Adult↗
PubMed2004

Bland-White-Garland syndrome. Surgical treatment using a minimal-invasive approach.

We report the surgical treatment of a Bland-White-Garland syndrome (BWG-syndrome) of adult type in a 61-year old female patient. Coronary catheterization revealed an anomalous origin of the left coronary artery from the trunk of the pulmonary artery. Based on excellent collateral perfusion of the artery from the right coronary artery, ligation near its origin from the pulmonary artery was attempted via a minimally-invasive approach. No saphenous vein bypass was implanted, no reimplantation of the anomalous vessel in the aorta was performed. The patient recovered uneventfully without signs of ischemia. Appearance of BWG-syndrome in adults is very rare, especially without symptoms of myocardial ischemia. The different modalities of the treatment of these syndromes in adult patients are often debated. In this case, closure without revascularisation appeared to be appropriate.

Collateral Circulation↗
PubMed2003

Post-operative hypoalbuminaemia and procalcitonin elevation for prediction of outcome in cardiopulmonary bypass surgery.

BACKGROUND: Because few studies have addressed postoperative hypoalbuminaemia in relation to hospital mortality, we evaluated this association and the prognostic value of increased procalcitonin (PCT) after cardiopulmonary bypass (CPB) surgery. METHODS: In 454 consecutive patients undergoing CPB, minimal serum albumin, colloid osmotic pressure (COP) and maximal PCT were retrospectively obtained from the 2nd to 10th postoperative day. Receiver operating characteristic (ROC) and multiple regression analyses determined independent predictive strength for 28-day mortality from preoperative albumin, Euroscore, postoperative minimal albumin and COP, and maximal PCT. Cut-off points for the four strongest predictors were calculated by the area under the curve (AUC) in the ROC for the 28-day mortality. RESULTS: Maximal PCT showed the largest AUC (0.85; 95% CI 0.79-0.90) and the highest relative risk (RR 12.17; 95%CI 5.26-28.16; P < 0.001), compared with postoperative albumin (AUC 0.72; 95% CI 0.62-0.81; RR 5.35; 95%CI 2.99-9.56; P < 0.001) and EuroSCORE (AUC 0.73; 95%CI 0.63-0.83; RR 4.48; 95%CI: 1.78-11.28; P < 0.01). By logistic regression, postoperative albumin was the strongest predictor of mortality (odds ratio 0.86; 95% CI 0.84-0.89). Cut-off values for predicting 28-day mortality were found for postoperative albumin and PCT at 17.8 g l(-1) and 2.5 ng l(-1), respectively. A slight but significant inverse correlation between PCT and albumin was found. Patients with albumin less than the cut-off showed significantly higher median values for PCT levels (2.5 vs. 1.0 g l-1), a higher 28-day mortality rate (20.8% vs. 4.5%), and a longer ICU stay (6 vs. 3 days) in comparison with patients with minimal albumin greater than 18 g l(-1). CONCLUSIONS: Post-operative serum albumin <18 g l(-1) and PCT >2.5 ng l(-1) are predictive for a higher 28-day mortality rate in cardiosurgical patients. Both peak PCT and minimal albumin were better outcome predictors than the Euroscore, which better represents the preoperative condition of the patient.

Aged↗
PubMed2002

Redo- extirpation of a cardiac leiomyosarcoma to avoid transplantation.

Cardiac leiomyosarcoma is a very rare entity that is found in less than 0.2 % of all cardiac tumors. At the time of primary diagnosis, it often shows advanced local invasion or may even be metastasized. Thus, complete resection can not easily be achieved. Cardiac transplantation has been reported as a therapeutic option. Here, we report on a case of a leiomyosarcoma reoccurrence arising 2 years after initial surgery. We performed a radical redo-extirpation without the necessity of transplantation.

Adult↗
PubMed2002

Tissue engineering of heart valves -- current aspects.

Tissue engineering of heart valves is an evolving research field. Driven by the shortcomings of the heart valve substitutes currently available, such as need for anticoagulation, susceptibility to infections, inability to grow and autorepair, the multidisciplinary approach for designing and growing viable heart valves identical to the native heart valves has begun. The following will give an update of the recent developments, current limitations and potential future applications of tissue-engineered heart valves.

Animals↗
PubMed2002

Outcome of patients after cardiac surgery transferred to other hospitals following prolonged intensive care stay.

BACKGROUND: The steady rise in complex cardiac procedures as well as the increase in comorbidity often result in a prolonged intensive care unit (ICU) stay. As a consequence, considerable numbers of patients have to be transferred to other hospitals so that the primary institution can maintain its capacity. The purpose of this study was to investigate the outcome of these patients. METHODS: 1,175 consecutive patients underwent various open heart procedures. 115 patients (9.8 %) requiring prolonged ICU treatment were retrospectively analyzed. 74 patients (EuroSCORE 8.1) underwent transferral to either rehabilitation units with ventilation capacity, multidisciplinary ICUs, or cardiac ICUs. 41 patients (EuroSCORE 7.9) remained in our hospital. Morbidity, mortality, and clinical condition were assessed and compared. RESULTS: Transferred patients exhibited an overall mortality of 38 % compared to only 17 % in patients who remained. Mortality was 81 % in rehabilitation units, 30 % in multidisciplinary ICUs, and 16 % in cardiac ICUs. 66 % of the survivors among the transferred patients showed significantly impaired clinical condition (NYHA III-IV) compared to 33 % who showed a good postoperative condition (NYHA I-II). The patients who remained exhibited 44 % NYHA III-IV and 56 % NYHA I-II. CONCLUSION: Transferral of patients after prolonged intensive care stay to external hospitals carries significant risks for early death and impaired outcome. However, transferral to cardiac ICUs appears to be an adequate option. Further studies may identify potential subgroups of patients who do not benefit from transferral.

Adult↗
PubMed2001

Retrograde versus antegrade crystalloid cardioplegia in coronary surgery: value of troponin-I measurement.

BACKGROUND: The optimal route for delivery of cardioplegia is still in debate in patients with ischemic heart disease. Cardiac troponin-I is a new marker with the potential for detection of minor differences in myocardial ischemia. METHODS: In a prospective randomized trial 58 patients undergoing elective coronary artery bypass grafting for two- or three-vessel coronary artery disease were divided into groups with antegrade (group A, n = 29) and retrograde (group R, n = 29) application of crystalloid cardioplegia (St. Thomas II). Patients with major risk factors were excluded. In addition to routine electrocardiogram monitoring, cardiac troponin-I and creatine kinase-MB activity were measured in all patients preoperatively at 2, 5, 8, 24, and 48 hours after aortic cross-clamp release, and at hospital discharge. RESULTS: In both groups, there were no differences regarding operative parameters. A significantly higher cardiac troponin-I concentration was observed in the antegrade group at 24 hours after cross-clamp (8.2 +/- 8.5 microg/L vs 3.2 +/- 3.1 microg/L; p = 0.02). Patients with subtotal stenosis or occlusion of one or more main coronary arteries showed significantly lower cardiac troponin-I levels after retrograde application. CONCLUSIONS: Lower concentrations of the cardiac troponin-I marker after retrograde application of cardioplegia indicate advantages of myocardial protection in ischemic heart disease.

Aged↗
PubMed2001

Aerosolized iloprost for severe pulmonary hypertension as a bridge to heart transplantation.

Preexisting pulmonary hypertension in pediatric patients is associated with poor outcome after cardiac transplantation because of donor right ventricular dysfunction. To avoid a combined heart-lung transplantation in a 17-year-old patient, we used an intensified pretreatment with intravenous prostacyclin and dobutamine combined with an inhalative therapy with the aerosolized prostacyclin-analog Iloprost. With this regimen, the patient was hemodynamically stabilized for the waiting period of 21 days after which an uneventful cardiac transplantation was performed.

Adolescent↗
PubMed2001

Coronary artery bypass grafting surgery without the routine application of blood products: Is it feasible?

OBJECTIVE: Fresh frozen plasma (FFP) substitution is currently standard practise in cardiac surgery. In this study we investigate whether elective coronary artery bypass grafting (CABG) surgery is feasible without the administration of blood products compared to the substitution of fresh frozen plasma. PATIENTS AND METHODS: From September 1997 to April 1998, 120 consecutive patients underwent CABG surgery at our institution. In the FFP group patients (n=60; men, n=43; women, n=17; mean age: 64+/-8.5 years) received 4 units of fresh frozen plasma (FFP) intraoperatively. In comparison, patients in the control group (n=60; men, n=44; women, n=16; mean age: 65+/-7.5 years) did not receive FFP. Main endpoints included perioperative hematologic parameters, blood loss, and the amount of blood products that were administered. RESULTS: Intraoperatively, the substitution of packed red blood cells (pRBC) in the FFP group was significantly higher compared with the control group (0.63+/-0.94 units/patient vs. 0.12+/-0.38 units/patient, P=0.001). Postoperatively, patients in the FFP group required significantly more pRBC products than patients in the control group (0.78+/-1.09 vs. 0.42+/-0.77, P=0.024). There were no significant differences in hemoglobin (FFP group: 99+/-11.1 g/dl; control group: 105+/-13.5 g/dl) and hematocrit levels (FFP group: 30+/-3.39%; control group: 32+/-4%). Also, no significant differences regarding the postoperative blood loss was observed between groups (FFP group: 588+/-224 vs. control group: 576+/-272 ml/24 h). CONCLUSIONS: This study clearly demonstrates that the avoidance of routine intraoperative FFP administration does not lead to an increase in blood loss postoperatively compared to patients that received FFPs. Furthermore, we did not observe increased requirements for postoperative FFP infusion in patients that did not receive FFPs intraoperatively.

Aged↗
PubMed2001

Renal carcinoma with caval vein infiltration and triple coronary disease: one-stage surgical management.

We report the one-stage surgical management in a 68-year-old patient with a renal cell carcinoma with extended intravascular growth into the inferior vena cava combined with severe triple coronary artery disease. After nephrectomy the resection of the intravascular tumor and caval reconstruction were performed in deep hypothermic circulatory arrest. Coronary revascularization was accomplished while rewarming. The postoperative course was uneventful. Nine months after this operation there are no signs of reoccurrence.

Aged↗
PubMed2001

Impact of PAF antagonist BN 52021 (Ginkolide B) on post-ischemic graft function in clinical lung transplantation.

BACKGROUND: Platelet activating factor (PAF) is associated with ischemia/reperfusion injury (I/R) after lung transplantation. Following promising experimental results, this prospective trial investigated the potential effect of PAF antagonist BN 52021 (ginkolide B) on clinical Euro-Collins (EC)-based lung preservation. METHODS: We analyzed 8 double-lung transplant patients in each of 3 groups. In the low-dose group (LDG), donor lungs were perfused with EC containing 2 mg/kg BN 52021, whereas we used 10 mg/kg in the high-dose group (HDG) and placebo in the control group (CG). Before reperfusing the first lung, we administered intravenously 120 mg BN 52021 (LDG), 600 mg BN 52021 (HDG), or placebo (CG). Hemodynamics in terms of pulmonary arterial pressure, pulmonary vascular resistance and serial determinations of the alveolo-arterial oxygen difference (AaDO(2)) were recorded. We measured blood levels of PAF pre-operatively and post-operatively, after 10 minutes and after 3, 8, 24, 48, and 144 hours. RESULTS: Within 32 hours, we noted a tendency toward better AaDO(2) in the LDG and the HDG compared with the CG (p > 0.05). We observed a significant improvement of AaDO(2) after 3 hours (HDG, p = 0.033) and 8 hours (LDG, p = 0.024), with poorest values in the CG. The PAF concentrations were lowest in the HDG, with significant deterioration 10 minutes after reperfusion. In contrast, placebo led to higher PAF levels. We measured significantly lower PAF concentrations (HDG vs CG) at 10 minutes and at 6 days post-operatively. CONCLUSIONS: Use of high-dose PAF antagonist BN 52021 can easily be combined with clinical preservation methods and may help optimize pulmonary function with reduced PAF levels, in the early post-ischemic period.

Diterpenes↗