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A Schiessler

Publications and source records attributed to A Schiessler.

15 recordsLinked to original sources

Recovery of end-organ failure during mechanical circulatory support.

To evaluate organ recovery during mechanical assistance, respiratory, hepatic and renal function parameters of 40 patients who underwent bridge-to-transplant procedures were reviewed retrospectively. Mechanical circulatory support was indicated if the hemodynamic and clinical status deteriorated despite pharmacotherapy with catecholamines, vasodilators, and intravenous use of the phosphodiesterase inhibitor enoximone. Sequelae of cardiogenic shock such as renal, hepatic and respiratory insufficiency were not considered a contraindication for mechanical support. The analysis of preimplant data such as serum creatinine, liver enzymes and pulmonary gas exchange did not identify any predictive indicator of irreversible organ damage. Functional recovery of preexisting respiratory, hepatic and renal dysfunction was found in 91%, 90%, and 85%, respectively. Subsequent transplantation, however, was affected by the number of failing organs prior to mechanical support. Of 17 patients with isolated organ failure prior to assist, 14 (82%) were transplanted. By contrast, 9 (75%) of 12 with combined failure of two organs, and only 6 (54%) of 11 patients with clinical patterns of three failing organ systems received transplants. In all patients who underwent successful transplantation, transplantability was associated with rapid organ recovery within 10 to 15 days after initiating mechanical assistance.

Adolescent

[Heart transplantation--indications and results].

Heart transplantation has become a standard procedure in the treatment for irreversible heart failure. Criteria for both recipients and donors have been extended. One year survival now reaches 81%. In the immediate postoperative course patients are endangered by infection. In the long-term course coronary artery disease of the transplanted heart becomes the most serious problem. Alteration of liver and kidney function due to chronic medication as well as malignancies and hypertension also occur. In case of chronic transplant failure retransplantation may be indicated. Acute cardiac failure before transplantation nowerdays can be treated by mechanical circulatory assist devices.

Follow-Up Studies

Thromboxane B2 urinary metabolites in patients undergoing cardiopulmonary bypass.

The urinary excretion of selected markers for renal injury and thromboxane metabolites was studied in 16 patients undergoing cardiopulmonary bypass (CPB). Excretion of both tubular and glomerular markers sharply increased on day 1 after CPB and remained elevated throughout the observation period (five days). Immunoreactive thromboxane B2 (i-TXB2, mainly reflecting 2,3-dinor-TXB2) and immunoreactive 11-keto-thromboxane B2 (i-11-keto-TXB2) were measured by direct enzyme immunoassays. TXB2, 2,3-dinor-TXB2 and 11-keto-TXB2 were also measured in selected samples by GC-MS. Urinary excretion rates of both i-TXB2 and i-11-keto-TXB2 markedly increased on day 1 after surgery and decreased thereafter. Following CPB, excretion rates of 2,3-dinor-TXB2 and TXB2 displayed parallel changes, suggesting that in these patients most urinary TXB2 derives from blood platelets rather than the kidney. Taken together, our observations do not support the hypothesis that acute renal injury observed after CPB is caused by exaggerated thromboxane biosynthesis in the kidney.

Adult

[Progress in heart transplantation].

Within the past 10 years, heart transplantation has become established as a standard procedure in heart surgery. Improvements in immunosuppressive therapy and diagnosis of graft rejection have been crucial. The criteria for transplantation have been broadened for recipients as well as for donors. Newborns, pediatric patients, diabetics, and patients with impaired renal function will no longer be excluded from transplantation due to improved postoperative therapy. Furthermore, progress has been made with assisted circulation. Patients with acute heart failure can now be bridged to transplantation.

Adult

[Coronary revascularization in end-stage coronary heart disease in relation to assessment of myocardial vitality].

From 4/1986-12/1990, 177 pts. with endstage coronary artery disease (CAD) and left ventricular ejection fraction 10-30% received coronary artery bypass grafting (CABG). Preoperatively myocardial infarction rate was 1.5 (mean). Presupposition for CABGs was myocardial ischaemia at present demonstrated in myocardial viability test. 66.1% of the pts. had signs of ischaemia at e.c.g. after work. Additionally 97.6% of the pts. had myocardial ischaemia defined as redistribution in myocardial scintigraphy. Angina pectoris was present in 93.8% of the pts. preoperatively. 1-5 (mean 2.9) CABG per pt. were performed. 35 pts. received an internal mammaria bypass to the left coronary artery also. Operative mortality was 11.3% (1986-1990) and in 1990 alone 7.3%. Actuarial survival rate was calculated after one year to 87.4% after two years to 86.1% and after three years to 84.8%. Postoperatively all pts. were free from angina pectoris. 5 months after the operation e.c.g. after work was performed. The physical stress bearing area was increased to 82.7 Watt (mean) compared to 51.7 Watt (mean) preoperatively (p less than 0.001 s.). In conclusion pts. with endstage CAD and left ventricular ejection fraction 10-30% appeared to be good candidates for CABG with good prognosis and significant symptomatic improvement when signs of myocardial ischaemia are present preoperatively.

Aged

Patient selection for mechanical circulatory support as a bridge to cardiac transplantation.

Between 7/87 and 9/90 thirty-four patients underwent total artificial heart (Berlin Heart) (n = 2) or biventricular assist device (Berlin Heart) (n = 32) implantation as a bridge to cardiac transplantation. The time of mechanical support ranged from 2 to 60 days, for a mean of 19.2 days. Twenty-three patients received heart transplants, with 74% 30-day survival and 52% long-term survival. Implantation of a mechanical support system became indicated in those patients whose hemodynamic and clinical condition deteriorated despite treatment with enoximone in addition to maximal sympathomimetic medication. The strategy to administer enoximone routinely was the result of a prospective study on 24 pretransplant patients in whom enoximone therapy reduced the need for mechanical assistance by 62%. At the time of device implantation shock-related organ impairment such as cerebral, renal, hepatic, and respiratory dysfunction was present in 62% of patients. In addition, 7 patients had pneumonia. During mechanical support complete recovery of end-organ failure and resolution of pneumonia was observed in the majority of patients. The results indicate that end-organ dysfunction per se should not be considered a contraindication to mechanical circulatory support as a bridge to cardiac transplantation. However, further clinical investigations are needed to identify predictive indicators of irreversible organ damage.

Adult

[Stable postoperative phase after total artificial heart-replacement in animal-experiments (author's transl)].

Presented are results of an analysis of more than 30000 data which were sampled in seven long-surviving calves after total artificial heart-replacement (more than 35 days survival). The continuity of 24 types of data (hemodynamic, labor- and physical data) are transformed for every animal in time-equidistant datafields and after this an average continuity for all seven animals is calculated and plotted. Twenty days after the operation the data have reached the preoperative values in nearly all cases, indicating a stable phase starting, according to the clinical condition of the animals.

Animals

Mechanical circulatory support and heart transplantation.

Mechanical circulatory support systems are currently in clinical use to keep patients alive with the aim of either cardiac recovery after open heart surgery, myocardial infarction and after heart transplantation with acute graft failure, or as a bridge to transplantation in heart transplant candidates. At the German Heart Institute the "Berlin Heart" mechanical circulatory support system has been used invariably since 1987. Up to 1991 there were 22 patients in the "recovery" group. Four patients could be weaned from the system, but only one patient was discharged from the hospital. In 65 patients mechanical circulatory support systems were implanted as a bridge to transplantation, 39 patients had transplants, and 22 patients left the hospital. Risk factor analysis in the bridging group revealed that previous heart surgery, infective pneumonia, shock-related coagulation disorders, and an age greater than 50 years had an unfavorable influence on patient survival. It is concluded that patients may be kept alive for weeks and months after any kind of cardiogenic shock. Complete cardiac recovery may be achieved in the case of early posttransplant graft failure. Reliable prediction of outcome in the bridge to transplantation group requires further experience.

Female

Clinical use of the Berlin Biventricular Assist Device as a bridge to transplantation.

The Berlin Artificial Heart System/Biventricular Assist Device (BVAD) was used in 38 patients. 1) Twenty-eight patients were awaiting cardiac transplantation (Tx) (age 23-56 yrs). All patients had contraindications not allowing immediate Tx. 2) Five patients were emergency cases not on our Tx list (postcardiotomy cardiac failure, acute myocarditis) (age 28-59). 3) Five patients were post Tx patients with graft failure (age 22-52). Extracorporal circulation was used for implantation of the BVAD. In group 1, 21 of 28 patients (pts) recovered, and all were subsequently transplanted after 6 hours to 39 days, when all organ function was restored. In 7 pts, mechanical circulation was terminated after 1-40 days because of further deterioration. Five of the transplanted pts died, 14 pts survived (greater than 30 days), and 2 pts were just transplanted with satisfactory postoperative courses. Of group 2 and 3 pts, two were successfully weaned. In one patient the allograft recovered after 11 days of support.

Cardiac Output