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Biomedical subjects

S Christiansen

Publications and source records attributed to S Christiansen.

At least 19 recordsLinked to original sources

Ultrasound imaging of infrainguinal arterial disease has a high interobserver agreement.

OBJECTIVES: to evaluate and compare the operator dependency of duplex ultrasound and digital subtraction arteriography (DSA) in patients suffering from chronic lower limb ischaemia. DESIGN: prospective and blinded validation study. MATERIAL: twenty-six consecutive patients (13 male and 13 females) with severe claudication (n=6, 23%), rest pain (n=7, 27%) or tissue loss (n=13, 50%). METHODS: two physicians independently performed a duplex scan of the lower limb from groin to foot (15 segments). Segments were classified as insignificantly (<50% stenosis) or significantly (>50% stenosis or occlusion) diseased. DSA was performed within 24h of the duplex scanning and was independently reported by two radiologists in the same manner. Interobserver agreement was assessed for both diagnostic methods. After 10 months the arteriograms were reassessed and the intraobserver agreement calculated. RESULTS: for the limb as a whole the interobserver agreement was good and similar for both duplex and DSA, with kappa-values of 0.79 (95%-CI: 0.72-0.86) and 0.80 (0.74-0.87). In the femoral, crural and pedal segments the interobserver agreement was similar for both methods. The intraobserver agreement between the two DSA readings was 0.84 (0.79-0.90). CONCLUSION: ultrasound is comparable to arteriography when visualising arterial occlusive disease in patients with chronic lower limb ischaemia.

Adult↗

[First experiences with a miniaturized heart-lung-machine].

Conventional heart-lung-machines (HLM) used for many cardiosurgical procedures lead to an impaired function of nearly all organs. This deleterious effect may be reduced by miniaturized HLMs. Therefore we report on our first experiences in 9 patients (4 women, 5 men) undergoing beating heart coronary artery bypass grafting from 10/01 to 04/02 in our department employing a miniaturized HLM with the Deltastream extracorporeal rotary blood pump. Eight patients had an uneventful postoperative course, one patient died on the first postoperative day. Using this miniaturized HLM beating heart coronary artery bypass grafting was successful in all patients. Further studies are necessary to support these results.

Aged↗

Does a suitable animal model for research on partial left ventriculectomy exist? Animal models for PLV.

Partial left ventriculectomy is a new surgical option quickly introduced into clinical use worldwide for treating end-stage heart failure in patients with dilated cardiomyopathy. Due to the overwhelming success of this new kind of surgical treatment for dilated cardiomyopathy, experimental research on the physiological and pathophysiological basis was initially not performed. Now, demands for an appropriate animal model have arisen more and more since the outcome of patients treated by partial left ventriculectomy has differed considerably. This review summarizes available experimental models for heart failure in large animals, and discusses their suitability for research on partial left ventriculectomy.

Animals↗

Treatment strategy and perioperative risk in patients with idiopathic thrombocytopenic purpura undergoing cardiac surgery.

Patients suffering from idiopathic thrombocytopenic purpura undergoing cardiac surgery with extracorporeal circulation may be at increased risk for postoperative bleeding complications. Therefore, different treatment strategies, such as conservative treatment, splenectomy, transfusion of platelet concentrates and therapy with immunoglobulins have been proposed. We report on our experiences with preoperative immunoglobulin treatment in selected patients with special regard on the optimal dosage.

Aged↗

Successful cardiac transplantation after Novacor implantation in a HIT II-patient using heparin.

The anticoagulative management of patients tested positive for heparin-induced thrombocytopenia type II (HIT II) and requiring cardiac surgery has been difficult until now. A special challenge arises, when left ventricular assist devices have to be implanted for bridging to cardiac transplantation. We report on the anticoagulative management of such a patient, based on the consideration of HIT II-pathophysiology and using heparin for Novacor LVAD implantation and cardiac transplantation.

Adult↗

Preoperative immunoglobulin treatment in patients with Werlhof's disease undergoing cardiac operation.

BACKGROUND: Patients with Werlhof's disease and undergoing a cardiac surgical procedure with cardiopulmonary bypass are at increased risk for bleeding complications. We report the usefulness of preoperative immunoglobulin treatment in selected patients. METHODS: Between May 1995 and July 1998, 10 patients with Werlhof's disease underwent a cardiac surgical procedure with cardiopulmonary bypass in our department. Five patients with mean platelet counts of less than 80x10(9)/L received immunoglobulin therapy preoperatively (group 1). The other 5 patients with mean platelet counts higher than 80x10(9)/L were not so treated (group 2). RESULTS: In group 1, mean platelet count increased from 54x10(9)/L 5 days before operation to 112x10(9)/L after immunoglobulin treatment (p = 0.018) and did not fall to less than 60x10(9)/L postoperatively. Patients in group 1 received 16 units of packed red blood cells and 5 units of platelet concentrate. Patients in group 2 required 24 units of packed red blood cells, 5 units of platelet concentrate, and 23 units of fresh frozen plasma. Only 1 patient (group 2) had a surgical bleeding complication that required reexploration. Mean drainage loss was 1,100 mL in group 1 and 1,210 mL in group 2. CONCLUSIONS: Our data demonstrate that immunoglobulin treatment of patients with Werlhof's disease and mean platelet counts of less than 80x10(9)/L significantly augments platelet counts preoperatively. It may be useful in selected patients.

Adult↗

Anticoagulative management of patients requiring left ventricular assist device implantation and suffering from heparin-induced thrombocytopenia type II.

BACKGROUND: Heparin-induced thrombocytopenia type II (HIT II) is a rare but life-threatening side effect of heparin therapy. We describe the perioperative anticoagulative management of patients tested positive for HIT II and requiring implantation of a left ventricular assist device (LVAD). METHODS: We report on 3 patients with a different perioperative anticoagulative management (preoperative, intraoperative, and postoperative anticoagulation with danaparoid-sodium; preoperative anticoagulation with recombinant hirudin, anticoagulation with danaparoid-sodium intraoperatively and postoperatively; preoperative anticoagulation with recombinant hirudin, intraoperative anticoagulation with heparin, and postoperative anticoagulation with danaparoid-sodium) and discuss the difficulties of the treatment. RESULTS: Anticoagulation with alternative drugs such as recombinant hirudin and danaparoid-sodium led to serious and life-threatening bleeding complications as well as to thromboembolic events in the first 2 patients. Therefore the third patient underwent LVAD implantation using heparin for intraoperative anticoagulation to avoid administration of high doses of recombinant hirudin or danaparoid-sodium. Despite very low anti-factor Xa activities, when using danaparoid-sodium postoperatively, the patient suffered from a bleeding complication on the 4th day after LVAD implantation requiring reexploration. CONCLUSIONS: In selected cases (negative heparin-induced platelet aggregation (HIPA) test at the time of LVAD implantation and continuation of postoperative anticoagulation with recombinant hirudin or danaparoid-sodium), heparin may be used for LVAD implantation in HIT II patients to reduce bleeding complications.

Adult↗

Surgical management of extensive lipomatous hypertrophy of the right atrium.

Lipomatous hypertrophy of the right atrium is a rare lesion that is usually limited to the interatrial septum. The authors report on a patient that suffered from an extensive lipomatous hypertrophy, which protruded into the right and left atrium as well as the superior vena cava and caused inflow obstruction. Therapeutic management is discussed.

Cardiomegaly↗

Impact of malignant hematological disorders on cardiac surgery.

BACKGROUND: Patients suffering from malignant hematological disorders may be at increased risk, when undergoing cardiac surgery. We report on our experiences with ten cardiac procedures in nine patients (3 males, 6 females, 19-85 yr old, mean age 61 yr). METHODS AND RESULTS: There were two patients with Hodgkin's lymphoma and one patient each with Waldenstrom's syndrome, multiple myeloma, polycythemia, myelodysplasia, chronic lymphocytic leukemia, non-Hodgkin's lymphoma and idiopathic aplastic anemia. Cardiac diseases included coronary artery disease in six, aortic stenosis in two, and mitral insufficiency in one patient. Consecutively, cardiac procedures were coronary artery bypass grafting in six, aortic valve replacement in two, and mitral valve replacement in one patient. No patient died. Postoperatively, one patient suffered from a pericardial tamponade requiring surgical removal and 5 months later from a prosthetic endocarditis necessitating change of the bioprosthesis. One patient developed a superficial wound infection, which was treated conservatively. Four patients received no blood products. Altogether, we transfused 32 packed red blood cells, seven units of fresh frozen plasma and 16 platelet concentrates. Total drainage loss was 883 ml (250-1510 ml). CONCLUSIONS: Cardiac surgery in patients suffering from malignant hematological disorders may be performed, but carries an increased morbidity. Therefore, indications for cardiac procedures must be carefully considered.

Adult↗

Are patients with Werlhof's disease at increased risk for bleeding complications when undergoing cardiac surgery?

BACKGROUND: It is generally assumed, that patients with Werlhof's disease (WD) are at increased risk for bleeding complications when undergoing cardiac surgery with extracorporeal circulation. Therefore we performed this case control study to estimate the real risk for bleeding complications of these patients. METHODS: Between 05/95 and 07/98, ten patients with WD (eight males, two females) underwent cardiac surgery employing extracorporeal circulation (WD-group). Five of these patients with platelet counts below 80/nl were treated by immunoglobulins preoperatively. Each patient with WD was matched to five patients without WD (no-WD-group) using diagnosis, age, gender, ejection fraction, number of distal anastomosis and body-mass-index as matching criteria. RESULTS: Mean number of platelet counts were significant lower in the WD-group than in the no-WD-group despite a significant increase of platelet counts after immunoglobulin treatment (54/nl-->112/nl, P=0.018). On the day before, directly after and on the first day after surgery they were 141/nl vs. 215/nl (P=0.012), 75/nl vs. 147/nl (P=0.001) and 93/nl vs. 136/nl (P=0.009). Accordingly, patients of the WD-group received significantly more platelet concentrates than patients of the no-WD-group (mean number of platelet concentrates: 2.3 versus 0.7, P=0.007). Total drainage loss via the mediastinal chest tubes was almost identical (1197 ml in the no-WD-group and 1140 ml in the WD-group). One patient of each group suffered from a bleeding complication requiring reexploration. Three patients of the no-WD-group (6%) and one patient of the WD-group (10%) expired postoperatively unrelated to WD. CONCLUSIONS: Patients with WD may possibly undergo cardiac surgery without a markedly enhanced risk for bleeding complications despite a more than usual transfusion requirement and significantly lower platelet counts perioperatively.

Adult↗

Diagnosis, treatment and outcome of patients with Askin-tumors.

Askin tumors are highly malignant small-round-cell tumors of the thoracopulmonary region, which occur rarely. Therefore, we report on our experiences with eight patients (5 male, 3 females), who were treated in our department between 11'94 and 10'97 (age: 9-40 years, mean age: 20.5 years). All Askin tumors were diagnosed by histological and immunohistochemical examinations as well as molecular genetic proof of characteristic translocations. In all patients, the tumor arose from the chest wall, infiltrating adjacent ribs and parts of the lung. At the time of first diagnosis, five patients did not reveal any metastases. One patient suffered from intrapulmonary metastases and two patients from an infiltration of the diaphragm and of adjacent vertebral bodies. Treatment consisted of a pre- and postoperative (radio-) chemotherapy according to the EVAIA protocol and a radical tumor resection in all patients. The postoperative course was uneventful in seven patients, one patient suffered from pneumonia after multiple wedge resections for intrapulmonary metastases. Four patients, in whom primary tumor resection was complete, are alive 14, 20, 35 and 84 months after first diagnosis - only one patient had to undergo a second operation for a local relapse 17 months after first diagnosis. The other 4 patients, who suffered from a very extensive primary tumor, expired 13, 17, 18 and 39 months after the diagnosis was made. Our data demonstrate that Askin tumors require an aggressive multimodality treatment consisting of pre- and postoperative chemotherapy, radical surgical resection and postoperative irradiation, which may be performed preoperatively in selected cases, too.

Adolescent↗

Small thymomas and myasthenia gravis: a poorly understood association.

Myasthenia gravis (MG) is associated with about 20% of all patients with thymomas, but the occurrence in patients with small thymomas is rare. The pathogenetic relevance of these small thymomas for MG is poorly understood until now. We report on the clinical course of a 39-year-old female patient suffering from MG and undergoing thymectomy for a small thymoma and discuss the pathogenetic importance of small thymomas for MG.

Adult↗