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Biomedical subjects

A Haverich

Publications and source records attributed to A Haverich.

At least 145 records · Page 8Linked to original sources
PubMed2000

Detection of CMV pneumonitis after lung transplantation using PCR of DNA from bronchoalveolar lavage cells.

BACKGROUND: Cytomegalovirus (CMV) is known as a common pathogen causing infections after lung transplantation. Rapid diagnosis of CMV infection is important for the initiation of a specific treatment. OBJECTIVE: Evaluation of methods for the rapid diagnosis of CMV pneumonitis. METHODS: The detection rates of CMV DNA in bronchoalveolar lavage (BAL) and bronchial brushes by polymerase chain reaction (PCR), of viral antigens (p52 and IE1) in BAL and of pp65 antigen in peripheral blood leukocytes were compared to the clinical status after lung transplantation. In 28 patients, 105 BAL, 96 blood samples and 14 brushes were analyzed. RESULTS: In 6 patients, a total of eight episodes of CMV pneumonitis occurred. Five of the 6 with positive CMV antigens in BAL (p52 or IE1) showed signs of CMV pneumonitis. All episodes of CMV pneumonitis were detected by the PCR of BAL cells. Fourteen samples positive for CMV pp65 antigen in blood were negative in BAL PCR. In these cases, no clinical signs of pulmonary CMV infection occurred. Overall sensitivity, specificity, and positive and negative predictive values for the detection of CMV pneumonitis by PCR of BAL cells were 100, 98.9, 88.9 and 100%, respectively. In brush samples, PCR did not provide additional information to the results of the PCR of BAL cells. CONCLUSIONS: PCR of DNA from BAL cells is suitable for reliable and rapid detection of CMV pneumonitis.

Adolescent↗
PubMed2000

Matched-pair analysis of conventional versus endoluminal AAA treatment outcomes during the initial phase of an aortic endografting program.

PURPOSE: To investigate whether endovascular stent-grafts implanted during the early phase of an aortic endografting program have advantages over conventional surgical procedures for treatment of infrarenal aortic aneurysm (AAA). METHODS: In the first months of an endografting program, 37 patients (36 men; mean age 67.9 +/- 7.1 years, range 55 to 86) underwent AAA repair with endovascular implantation of a Vanguard (n = 17) or Talent (n = 20) bifurcated stent-graft. Data collected during the perioperative period and in follow-up were compared retrospectively to a matched group of 37 elective surgical patients. RESULTS: All endograft implantations were completed. Two type I and 6 type II endoleaks (21.6%) were seen postoperatively. Five type II sealed without intervention; 1 type I endoleak was corrected with an additional stent, but 1 type I and 1 type II endoleaks persisted despite attempts with coil embolization. Two (5.4%) endograft patients died during the perioperative period; however, this was not significantly different (p = 0.15) from the control group. In the mean follow-up of 12 +/- 6 months for both groups, 1 (2.7%) late conversion was necessary at 2 years for aneurysm expansion in an endograft patient with an unsealed type I endoleak. CONCLUSIONS: In our learning curve experience with aortic endografting, postoperative morbidity and mortality were higher in endograft patients compared to conventionally treated controls. Only in the endograft group was reoperation required during follow-up. Careful monitoring with periodic imaging studies is mandatory after endoluminal AAA treatment.

Aged↗
PubMed2000

Hemoptysis following left ventricular aneurysm repair: a misleading clinical sign.

We report on a 66-year-old man with severe hemoptysis following coronary artery bypass grafting and repair of a left ventricular septal defect after acute myocardial infarction. Initial diagnosis was delayed by misleading clinical symptoms and radiologic studies. Due to subfebrile temperature and sputum culture positive for Pseudomonas aeruginosa, he had been treated with antibiotics before reoperation. At reoperation, replacement of all foreign material and reconstruction of the ventricular repair with bovine pericardium resulted in reinfection with the same organism despite prolonged antibiotic therapy after 6 months. Removal of the pericardial tissue with direct suture closure of the ventricles and interposition of omentum led to complete healing of the infection without reoccurrence after 2 years.

Aged↗
PubMed2000

Examination of hemolytic potential with the On-X(R) prosthetic heart valve.

BACKGROUND AND AIM OF THE STUDY: Mechanical valves are known to produce chronic, subclinical hemolysis in most patients. Generally, haptoglobin is reduced to below normal in most patients, while lactate dehydrogenase (LDH) is increased to as much as 200% above the upper normal, sometimes resulting in anemia. The study was designed to investigate the clinical hemolysis of the On-X(R) prosthetic heart valve in a multicenter experience with a standard protocol and a single clinical laboratory. METHODS: Between September 1996 and August 1998, 248 patients underwent isolated valve replacement at 10 European centers. Blood samples were collected from these preoperatively and at 3-6 months and one year postoperatively. All samples were analyzed at a central laboratory, thus assuring poolability of the data. In total, 151 patients were tested at 3-6 months, and 62 at one year. Blood parameters measured were LDH, haptoglobin, hematocrit, total hemoglobin, red cell count and reticulocyte count. Paired analysis was used to compare preoperative baseline values with 3-6-month and one-year values. Data were analyzed with regard to both valve position and size. RESULTS: At 3-6 months and one year after surgery, average values for hematocrit, hemoglobin, red cell count and reticulocyte count were all near the center of the normal range, regardless of valve position or size. Statistically significant increases in red cell count and decreases in reticulocyte count occurred after both aortic valve replacement (AVR) and mitral valve replacement (MVR). These changes were of no clinical importance, but indicate that anemia has not occurred in these patients. At 3-6 months, haptoglobin was reduced to below normal in 86% of both AVR and MVR patients; this also occurred after one year and was statistically significant. Postoperatively, the mean LDH value in AVR was 228 U/l (91% of upper normal, 250 U/l) at 3-6 months, and 246 U/l (98% of upper normal) at one year. In MVR, these LDH values were 271 U/l (108% of upper normal) and 265 U/l (106% of upper normal). CONCLUSIONS: These results indicate that the On-X valve causes lower levels of chronic hemolysis in the immediate postoperative period and up to one year after surgery, especially when compared with reports of LDH elevations up to 200% of upper normal. Hemolytic anemia has not occurred in this patient population.

Aortic Valve↗
PubMed2000

[Advances and perspectives of heart-lung transplantation].

Thoracic organ transplantation has evolved as standard therapy in end-stage cardiac and pulmonary failure. Meanwhile more than 50,000 heart, 2500 heart-lung and 10,000 lung transplantations have been performed worldwide. Improvements in patient selection as well as in the postoperative management have led to 1-year survival rates of 70-90%. Long-term results are still influenced by the development of graft vessel disease, bronchiolitis obliterans syndrome and malignancies. Furthermore, indications and results of different procedures will be presented and new developments discussed.

Aged↗
PubMed2000

Clinical cardiac and pulmonary transplantation: the Hannover experience.

Thoracic organ transplantation has evolved from an experimental to a standard treatment modality for patients suffering from end-stage heart and lung failure. Based on our experience after 1,033 heart, lung, and heart-lung transplantation procedures performed at the Hannover Thoracic Organ Transplant Program, we report: 1. Survival rates following thoracic organ transplants were similar and ranged from 76-81% after one year. 2. The one-, 5-, 10- and 15-year survival rates for heart transplant recipients were 81%, 70%, 52% and 33%, respectively. 3. The 9-year survival rate for bilateral-lung transplant recipients (56%) was significantly better than that for single-lung recipients (36%, p < 0.05). 4. Heart-lung recipients had the poorest long-term survival rate in our program--18% surviving after 9 years. 5. Retransplantation has been an effective treatment for chronic graft dysfunction in lung transplant recipients, but was less successful when used to treat acute graft failure. The one-year regraft survival rate was 74% among 15 patients retransplanted for chronic graft failure compared with only 50% for 4 patients retransplanted for acute failure.

Academic Medical Centers↗
PubMed1999

Famciclovir treatment of chronic hepatitis B in heart transplant recipients: a prospective trial.

UNLABELLED: Hepatitis B may take a rapid and aggressive course in patients under immunosuppression. Nucleoside analogues have been shown to suppress viral replication effectively. To investigate the effect of famciclovir in immunosuppressed patients, 21 heart transplant recipients with chronic hepatitis B infection were included in a prospective study. PATIENTS AND METHODS: Patients have been treated with Famciclovir for a median of 14 months. Hepatitis B virus replication and biochemical parameters were regularly tested and liver biopsies were taken before treatment and after a median time of 7 months. HBV-polymerase was sequenced in all patients before therapy and in those patients who experienced virological breakthrough. RESULTS: Nineteen patients were treated for at least 6 months. Hepatitis B virus-DNA levels declined in all patients and became negative in 8 patients. Mean hepatitis B virus-DNA levels decreased from 199+/-269 to 34+/-53 pg/ml after 24 weeks (P=0.003). During treatment HBeAg became negative in five patients. Mean alanine aminotransferase decreased from 42+/-26 to 24+/-10 U/L (P=0.006). Histological analysis revealed improved inflammatory activity according to the Ishak-score in 11/16 (69%) patients. Total inflammatory activity scores decreased from 8 to 6 (median, NS), but interface hepatitis score (P=0.02) and lobular inflammation score (P=0.006) improved significantly. Median fibrosis scores fell from 5 to 3 (P=0.002). Three patients developed virological breakthrough on famciclovir after 7, 8, and 26 months of treatment showing HBV-polymerase amino acid changes L528 M, S567A, and I581K, respectively. CONCLUSIONS: Famciclovir improves not only biochemical and virological features but also hepatic inflammation and liver fibrosis in patients with chronic hepatitis B under heavy immunosuppression. Virological breakthrough may develop and requires close monitoring.

2-Aminopurine↗
PubMed1999

Ascending aortic replacement with aortic valve reimplantation.

BACKGROUND: Reimplantation of the native, structurally intact aortic valve within a Dacron tube graft in patients with aortic root aneurysms corrects annular ectasia and dilatation of the sinotubular junction. The durability of this valve repair with respect to the increased mechanical stress on valve cusps has been discussed, is quite controversial, and is yet unknown. METHODS AND RESULTS: From July 1993 to November 1998, a replacement of the ascending aorta with a repair of the aortic valve was performed in 75 patients (53 men and 22 women aged 50+/-19 years). Twenty-one patients (28%) had Marfan syndrome, and 11 patients (15%) had an aortic dissection, type Stanford A (6 acute, 5 chronic). In 17 patients (23%), concomitant replacement of the aortic arch was necessary. Clinical and echocardiographic follow-up was performed in 6- to 12-month intervals for a cumulative study period of 137 patient-years. No operative deaths occurred. Two patients (3%) died 5 and 20 months postoperatively. One additional patient experienced a transient ischemic attack within the first postoperative week. Three patients (4%) with progressive aortic insufficiency required aortic valve replacement after 9, 11, and 14 months. All other patients had no or mild aortic insufficiency. The repairs have now remained stable for </=65 months (mean, 22+/-20 months). Other valve-related complications did not occur. CONCLUSIONS: Our results demonstrate that this type of aortic valve repair achieves excellent results in selected patients. Perfect coaptation of valve cusps during the repair with no or only trace aortic insufficiency at initial echocardiography seems to be essential for durability.

Adolescent↗
PubMed1999

Predictors of proximal aortic dissection at the time of aortic valve replacement.

BACKGROUND: Type I aortic dissection develops in 0.6% of patients late after aortic valve replacement (AVR), and 13% of patients with type I aortic dissections have a history of AVR. Predictors of aortic dissection at AVR, however, have not been characterized. METHODS AND RESULTS: A study group of 33 patients with type I aortic dissection had aortic surgery 49+/-55 months after routine AVR. A group of 101 controls, who did not have morphological progression of aortic diameters >/=6 years after AVR, was used to identify predictors of postsurgical dissection. Multivariate analysis identified aortic regurgitation (P<0.002) and fragility (P<0.001) or thinning of the aortic wall (P<0.007) at AVR as predictors, associated with a 14%, 22%, and 7% probability of late aortic dissection, respectively. Clamping times, types of valve prostheses, concomitant coronary artery bypass grafting, and mean ascending aortic diameters of 43+/-10 mm at AVR did not predict late dissection. A separate analysis of 29 nondissecting aneurysms of the ascending aorta developing 104+/-64 months after routine AVR revealed younger age at AVR (P<0.003) and congenitally bicuspid aortic valves (P<0.03) as predictors of late aneurysm formation. CONCLUSIONS: Aortic regurgitation combined with fragile and thinned aortic walls in patients with moderate aortic dilation may reflect aortic root disease, with a high risk for postsurgical aortic sequelae if it is treated incompletely by isolated valve replacement.

Adult↗
PubMed1999

Attitudes of patients before and after transplantation towards various allografts.

BACKGROUND: The presence of an allogeneic graft inside the body may have psychological impact on transplant patients. It was the aim of this study to evaluate the attitude of patients before and after different types of organ transplantation towards organ allografts. METHODS: A total of 1,049 patients (722 patients after and 327 patients on the waiting list for either kidney, liver, heart, or lung transplantation) under care of a single transplant center were studied using a questionnaire with blinded analysis of the data. Mental condition of the patients, their attitude towards the allograft and its donor, emotional stress caused by a graft, and correlation of the attitudes with clinical and demographic parameters were analyzed. RESULTS: The self-reported mental condition of the patients was markedly and consistently better after organ transplantation; 27% of patients before and 60% after transplantation were in good mental condition. Sixty-two percent of transplant patients considered the graft as their own organ, 37% regarded it as a foreign organ now belonging to their body, and 1% considered it as a foreign body; among waiting list patients, 40%, 55%, and 5% assumed they would perceive their graft accordingly. The graft caused considerable emotional stress for 2% of transplant patients, whereas for 70% it did not cause any stress; the latter was assumed by 47% of patients before transplantation. Eleven percent of transplant patients frequently think about the origin of their graft, and 30% would like to have information about their donor. Knowledge about different religion, opposite sex, homosexuality, suicidal death, and age above 65 years of their donor would be of moderate or major concern for 0%, 3%, 21%, 24%, and 38% of the patients, respectively. CONCLUSIONS: The comprehensive survey shows that transplant patients incorporate their graft well into their body image. Emotional stress caused by the graft is very low and is generally less than assumed before transplantation. Knowledge about certain characteristics of the donor may cause increased concerns in some patients.

Adult↗
PubMed1999

Identification of 9 novel FBN1 mutations in German patients with Marfan syndrome.

We report 9 new mutations in German patients presenting with classical Marfan syndrome. All mutations occur in exons with calcium-binding (cb) epidermal growth factor-like (EGF) domains. Five mutations are missense involving exons 12, 27, 30, 44, and 52 with the resultant substitution of cysteine by phenylalanine (C504F), cysteine by tyrosine (C1129Y), tyrosine by cysteine (Y1261C), cysteine by serine (C1833S), and cysteine by tyrosine (C2142Y), respectively. The other four mutations are single base deletions in exons 39, 43, 48, and 58, at nucleotide A4826, C5311, T6018, and A7291, respectively, each resulting in frameshift with premature termination. Four mutations were detected in sporadic cases and are likely to be de novo.

Adult↗
PubMed1999

Enhanced oxygen delivery reverses anaerobic metabolic states in prolonged sandwich rat hepatocyte culture.

It must be assumed that current petri dish primary hepatocyte culture models do not supply sufficient amounts of oxygen and thus cause anaerobic metabolism of the cells. This is contrary to the physiologic state of the cells. In vivo the liver is a highly vascularized organ with a rather high blood flow rate of a mixture of arterial and venous blood. The aim of the present study was to show the oxygen dependence of primary rat hepatocytes in long-term culture and to define appropriate conditions that could allow hepatocytes to maintain tissue specific functions in an aerobic environment. To this purpose matrix overlaid hepatocytes were either cultured on gas-permeable (fluorinated hydrocarbon films) or gas-impermeable (polystyrene) supports at 10% and 20% ambient oxygen concentration (v/v), respectively. Tissue-specific functions were assessed by studying albumin and urea secretion as well as xenobiotic metabolism. The mRNA expression and catalytic activities of the cytoprotective antioxidant enzymes mitochondrial manganese superoxide dismutase (MnSOD), cytosolic copper and zinc superoxide dismutase, peroxisomal catalase, and cytosolic glutathione peroxidase were investigated to assess intracellular responses to the defined variations in oxygen supply. Hepatocytes could successfully be maintained at aerobic conditions in long-term culture on gas-permeable PTFE films. At 50% (10%, v/v) of currently used oxygen levels lactate accumulation was prevented, a plateau-like albumin secretion reestablished, urea secretion improved, and xenobiotic metabolism proceeded at physiological rates. mRNA expression of cytoprotective enzymes responded to the pericellular availability of oxygen and was most pronounced in the case of MnSOD. However, the biggest stress factor for the hepatocytes still appeared to be the isolation procedure, as mRNA expression and catalytic activities were most elevated shortly thereafter. In conclusion, this study clearly shows the oxygen dependence of primary rat hepatocytes in long-term culture and indicates means to establish appropriate conditions for the aerobic culture of primary rat sandwich hepatocytes with full maintenance of function. The long-term culture of hepatocytes on oxygenating supports at in vivo-like oxygen tensions therefore appears to be more physiologic and beneficial for the cells.

Aerobiosis↗
PubMed1999

Surfactant replacement in reperfusion injury after clinical lung transplantation.

BACKGROUND: Reperfusion injury remains a significant risk factor in the immediate postoperative course after lung transplantation. We report on our initial clinical experience of surfactant replacement in reperfusion injury after clinical lung transplantation. METHODS AND RESULTS: In 31 consecutive patients, lung (8 single lung, 16 bilateral lung) or heart-lung (7) transplantation was performed. In 6 patients, severe reperfusion injury developed and was treated with continuously nebulized surfactant. Compliance of the allograft increased 40 +/- 25 % within 3 h following treatment with surfactant. Alveolar arterial oxygen gradient decreased by 23 +/- 11 % after 3 h and by 35 +/- 20 % after 6 h. Normal graft function was reestablished within 1-3 days after transplantation. All treated recipients were extubated until the 6th postoperative day. The 30-day mortality for the 31 recipients was 3.3 %, the 1-year survival 84 %. CONCLUSIONS: Surfactant replacement may become a clinical method for treatment of reperfusion injury after lung transplantation.

Adult↗
PubMed1999

C1-esterase inhibitor in graft failure after lung transplantation.

Graft failure after lung transplantation may occur immediately after transplantation due to reperfusion injury or later due to rejection and infection. Although the pathological mechanisms are not completely known, the clinical findings are similar to the adult respiratory distress syndrome. In this condition, the blood coagulation contact system and the complement system are activated, leading to a capillary leak syndrome. Activation of the contact as well as the complement system is regulated by a common inhibitor, C1-esterase inhibitor (C1-INH). We report on two patients who received high doses of C1-INH for 2 days during graft failure either due to reperfusion injury immediately after transplantation or due to an acute rejection 2 months after double-lung transplantation. In both cases of graft failure, a capillary leak syndrome occurred with pleural effusions of 7 l to more than 10 l per day. In case 1 disturbance of gas exchange during severe reperfusion injury could not be treated effectively with other treatment modalities like nitric oxide ventilation or surfactant administration. With the use of C1-INH, pleural effusions reduced within 12 h, leading to normal graft function within 4 days. In the second recipient, acute rejection forced the use of extracorporeal membrane oxygenation (ECMO) within 24 h despite immunosuppressive therapy. After administration of C1-INH, pleural effusions reduced from 19 l per day to 300 ml within 3 days of treatment. ECMO was discontinued after C1-INH treatment and the patient extubated 2 weeks later. This experience indicates that C1-INH may play a role in the management of capillary leak syndrome after lung transplantation.

Capillary Leak Syndrome↗
PubMed1999

Eosinophilic alveolitis in BAL after lung transplantation.

Lung transplantation has become a therapeutic option for patients with end stage lung disease. However, outcome after transplantation is complicated by episodes of rejection and infections. Bronchoalveolar lavage is a valuable tool in monitoring patients after transplantation, since it allows the detection of pathogens. A marker specifically indicating rejection from changes in BAL fluid has not been found yet. Especially changes in differential cell count, like lymphocytosis or an increase in polymorphnuclear granulocytes, are unspecific. The role of high eosinophil levels in BAL has not been elucidated yet. We analyzed 25 BAL samples and clinical data of 4 patients who underwent lung transplantation and presented with recurrent episodes of eosinophilic alveolitis in BAL. All patients demonstrated a deterioration of clinical condition, lung function, and blood gas analysis during times of eosinophilia in BAL, compared to previous examinations. In all cases, eosinophilia in BAL was accompanied by rejection. All patients were finally treated with high doses of steroids, resulting in improvement of all parameters. Eosinophilia was not associated with significant changes in the IL-5 concentration in BAL or the pattern of IL-5 expression in BAL cells. In conclusion, eosinophilic alveolitis may indicate acute rejection in patients after lung transplantation, if other causes of eosinophilia are excluded.

Bronchoalveolar Lavage Fluid↗
PubMed1999

[Therapy of acute heart failure--surgical possibilities].

Acute heart failure represents a severe complication of several cardiac disorders. Coronary artery disease, acute bacterial endocarditis or acute decompensation of preexisting heart valve disease as well as endstage cardiomyopathies are the most frequent underlying causes. Because of the high mortality, surgical therapy should be always considered in addition to medical treatment. However, any therapeutical intervention must be based on an immediate diagnosis to evaluate type and severity of the disease. Surgical options comprise coronary revascularization, valve replacement or--reconstruction as well as a temporary support by means of mechanical assist devices.

Acute Disease↗
PubMed1999

[Hybrid technique for myocardial revascularization: value of combined minimal invasive bypass technique (MIDCAB) with interventional therapy (PTCA)].

BACKGROUND: Minimally invasive direct coronary artery bypass (MIDCAB) grafting without cardiopulmonary bypass (CPB) through an anterolateral minithoracotomy has become a promising therapeutical option especially in multimorbid, elderly and reoperative patients with single vessel disease. However, this procedure precludes complete revascularization in multivessel disease because the minithoracotomy limits the surgical access either to anterior or lateral or posterior vessels of the beating heart. To expand the benefits of the MIDCAB concept to patients with multivessel disease, new interdisciplinary approaches have recently been introduced. METHODS: Since December 1996, 26 patients (21 male, 5 female, mean age 56.6 +/- 18.8 years) underwent a "hybrid" revascularization performed as a primary MIDCAB procedure for grafting of the left anterior descending artery (LAD) with the left internal mammary artery (LIMA) followed by staged angioplasty and stenting of additional coronary lesions. RESULTS: After MIDCAB grafting, the postoperative course was uneventful in all patients. Coronary re-angiography after a median of 7 days revealed patent and functioning LIMA grafts in all patients. Applying subsequent percutaneous transluminal coronary angioplasty (PTCA) and occasional stenting (n = 8), a total of 31 lesions were treated successfully. Procedure related complications did not occur. All patients remained angina-free and no stress electrocardiographic changes were recorded. CONCLUSION: Our preliminary results of a "hybrid" approach to myocardial revascularization suggest that this concept is a safe and effective approach of complete revascularization for selected patients with multivessel involvement. Especially elderly and reoperative patients with significant comorbidity may benefit from hybrid procedures avoiding cardiopulmonary bypass and midsternotomy.

Adult↗