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H Oelert

Publications and source records attributed to H Oelert.

At least 37 records · Page 2Linked to original sources
PubMed2001

Troponin I concentrations of shed blood might influence monitoring of myocardial injury after coronary operations.

In a prospective study we evaluated the concentration of cardiac troponin I (cTnI) and creatine kinase activities (CK) in shed mediastinal blood in the early postoperative period after coronary artery bypass grafting (CABG). Forty seven patients who underwent first time elective CABG were studied. CTnI levels and CK activities in arterial blood and shed mediastinal blood were measured after admission to the intensive care unit (ICU) and 6 h after unclamping the aorta. Mediastinal shed blood samples were drawn from 23 patients (group A) before the filter of the cardiotomy reservoir and from 24 patients (group B) behind. Additionally, both markers were measured in blood samples collected from the cell-saver. There were no significant differences between both groups (A and B) with regard to perioperative parameters. Mean loss of mediastinal shed blood in all patients was 207 +/- 127 ml within the first 6 h after operation. There was a positive correlation between CK activities and cTnI concentrations in serum and mediastinal shed blood, but shed blood contained significantly higher concentrations of cTnI as well as CK activities than the circulating blood after admission to the ICU and 6 h after unclamping the aorta. At both time points the cTnI-concentrations and CK activities in shed blood in group B were lower than those in group A but much higher than in serum. The effects of the use of a blood filter diminishes with time. Mediastinal shed blood contains extremely high cTnI concentrations and CK activities. Retransfusion of higher quantities of shed blood might lead to false-positive diagnosis of perioperative myocardial infarction.

Aged↗
PubMed2001

Autogenous reconstruction of infected arterial prosthetic grafts utilizing the superficial femoral vein.

BACKGROUND: Prosthetic infection after reconstructive vascular surgery is a most serious complication, associated with high mortality and amputation rates. Following excision of the infected graft, several methods of reconstruction are available. We present here our experience with autogenous reconstruction of infected prosthetic arterial grafts using the superficial femoral vein (SFV). METHODS: From November 1995 to December 1999, we used the SFV in seven patients (mean age 70 years) for reconstruction of an infected aortobifemoral (n = 2), aortoiliac (n = 1), femorofemoral bypass (n = 1), femorotibial (n = 2) and carotid crossover bypass (n = 1). Treatment encompassed complete prosthetic excision and autogenous reconstruction with the SFV alone or as a spliced graft with the greater saphenous vein (GSV) or basilic vein. RESULTS: There were no perioperative deaths or amputations. Two patients exhibited transient moderate swelling of the donor limb. In the follow-up, six patients are alive and well without any signs of recurrent infection. One patient died with an unrelated cause 24 months postoperatively. All donor limbs were asymptomatic for venous congestion in the long-term follow-up. CONCLUSION: The SFV provides a reliable tool for autogenous reconstruction after resection of infected prosthetic arterial grafts. Harvesting the SFV is well tolerated as long as the deep femoral and the popliteal vein are preserved.

Aged↗
PubMed2001

Patterns and diagnostic value of cardiac troponin I vs. troponin T and CKMB after OPCAB surgery.

BACKGROUND: Cardiac troponin I (cTnI) has been shown to be a specific marker for myocardial injury in cardiac surgery. The object of this prospective study was to determine the patterns and kinetic and diagnostic value of cTnI, cardiac troponin T (cTnT), and creatine kinase MB (CKMB) activity after minimally invasive coronary revascularization using an octopus device on the beating heart (OPCAB). METHODS: 48 patients (33 male/15 female, mean age 68.3 +/- 8.7 years) underwent their first elective OPCAB surgery with median sternotomy without mortality. The mean number of grafts was 2.0 +/- 0.8 per patient. Preoperative mean ejection fraction was 56.6 % +/- 14.9%. CTnI and T levels, total creatine kinase (CK) and CK-MB activity in the serum were measured before operation, at arrival at the ICU, and 6, 12, 24, 48 and 120 hours afterward. Serial 12-lead ECGs were recorded preoperatively and at days 1, 2 and 5. The relationship between perioperative data and postoperative cTnI and cTnT levels and CKMB were statistically identified for all variables. RESULTS: The best cutoff value for cTnI was 8.35 micrograms/l. The patients were grouped by the ECG findings and maximal slopes of cTnI postoperatively (group I: unchanged ECG and cTnI < 8.35 micrograms/l, n = 38; group II: unchanged ECG and cTnI > 8.35 micrograms/l n = 6; group III: Q-wave in ECG and cTnI > 8.35 micrograms/l, n = 4). Baseline serum concentrations of cTnI were in the normal range, and significantly increased after surgery with a peak 24h after the operation. Maximal slopes of cTnI ranged in group II between 9.1 and 18.0 micrograms/l, and in group III between 35.9 and 88.8 micrograms/l. There was strong concordance between maximum cTnI, cTnT (p < 0.0001) and CK-MB levels (p = 0.003). First cTnI levels immediately post-op correlated with the maximum cTnI levels during the postoperative course (p = 0.009). CONCLUSIONS: CTnI after minimal invasive surgery shows a characteristic pattern with a maximum at 24h after the operation. The measurement of postoperative biochemical marker concentrations, specially cTnI, reflects myocardial injury incurred during the procedure. It is an accurate method for confirming or excluding a perioperative myocardial injury diagnosis after OPCAB surgery.

Aged↗
PubMed2001

Value of echocardiography in patient follow-up after surgically corrected type A aortic dissection.

BACKGROUND: To identify patients (pts) at risk of late complications, follow-up after surgery for type A aortic dissection is essential. We assessed the value of echocardiography to monitor patients after surgery for type A aortic dissection. METHODS: 80 out of 108 pts operated between 1989 and 1999 for type A aortic dissection survived surgery. 62 pts with at least one TEE, CT or MRI examinations during follow-up were included in this study. All pts had transthoracic echocardiography (TTE), 53 transesophageal echocardiography (TEE), 51 had CT, and 39 had MRI. RESULTS: At the first follow-up, 12 of 48 pts with aortic valve sparing surgery presented with aortic insufficiency >I degrees detected using echocardiography. 16 pts evolved a distal aortic aneurysm of over 5 cm, all seen in TEE, CT and MRI. A distal intimal flap was present in 39 pts and could be seen in TEE, CT and MRI in all patients. A new proximal aortic root dissection took place in 5 pts. Progressive aortic pathology led to reoperation in 9 pts. TEE was especially useful in 2 pts to confirm redissection, in 1 pt to rule out redissection assumed by CT, and in 1 with paraprosthetic blood flow after ascending aortic replacement. MRI led to additional information in 1 patient with false aneurysm of the distal anastomosis and 1 with redissection not seen in TEE 6 month before. CT and MRI were superior to TEE in demonstrating aortic arch pathology, whereas TEE was more effective in showing the flow pattern and residual entry sites. CONCLUSIONS: Echocardiography is an effective and cost-saving diagnostic tool to monitor pts after surgery for type A aortic dissection, and should be the method of choice to ascertain aortic pathology initially after surgery. Follow-up intervals and need for additional CT or MRI should be determined afterwards according to specific pathologies.

Adult↗
PubMed2001

Surgical treatment of pulmonary artery sarcoma.

OBJECTIVE: Pulmonary artery sarcomas are rare and usually fatal tumors. The diagnosis is difficult and delayed in most cases. Newer imaging techniques could allow early diagnosis in patients with symptoms of pulmonary vascular obstruction. Surgical resection improves clinical symptoms and offers the only chance of cure. We report the case histories of 7 patients with primary pulmonary artery sarcomas treated by surgical resection with or without adjuvant therapy. METHODS: Seven patients (3 women and 4 men; mean age, 52.3 years; preoperative New York Heart Association functional class III/IV, n = 5/2) underwent operations. Malignancy was preoperatively suspected in 5 patients, and 2 patients had a presumptive diagnosis of chronic pulmonary embolism. Tumor resection with partial or total prosthetic replacement (n = 2), reconstruction (n = 5), or both, of central parts of the pulmonary arteries was performed in 6 patients. Thromboendarterectomy was necessary in 4 patients, and pneumonectomy was necessary in 2 patients. Six patients received adjuvant therapy. RESULTS: There was no perioperative mortality. All patients had a substantial improvement in exercise tolerance and hemodynamics 3 months after their operations. Four patients died 7, 9, 18, and 19 months after their operations because of recurrent tumor or pulmonary metastases. Two patients are alive 21 and 35 months after primary surgical repair, with pulmonary metastases detected by computed tomographic scans. One patient is alive 62 months after resection without clinical or radiologic signs of tumor recurrence or metastasis. CONCLUSIONS: Early diagnosis of primary pulmonary artery sarcomas can be improved by computed tomography and magnetic resonance scanning. Radical surgical resection probably presents the only chance for cure. The role of neoadjuvant or adjuvant treatment modalities has to be defined. Pulmonary artery sarcoma need not necessarily be a fatal diagnosis.

Adult↗
PubMed2001

Expression of the proto-oncogene c-myc in human stenotic aortocoronary bypass grafts.

Proliferation and differentiation of vascular smooth muscle cells (VSMC) are central events in vascular pathobiology and play a major role in the development of stenotic and restenotic lesions. The proto-oncogene c-myc and other early cell cycle-regulating genes have been implicated in the induction of cell proliferation and differentiation under diverse pathophysiological conditions. In the present study we analyzed c-myc mRNA expression by indirect nonradioactive in situ hybridization technique (NISH) in human stenotic venous bypass grafts (n = 32) retrieved during re-do operations of coronary artery disease and compared the results with 28 native veins (vena saphena magna) from the same patients. Stenotic bypass grafts showed enhanced c-myc expression located predominantly in VSMC in the media and neointima (severity score: ++-+++, 32/32 stenotic veins). In native veins we observed only low levels of c-myc mRNA (severity score: +, 28/28 native veins), all signals were restricted to endothelial cells of either the innermost intimal layer or of the vasa vasorum. Our in situ hybridization studies demonstrate enhanced mRNA expression of the proto-oncogene c-myc in stenotic venous bypass grafts. These results suggest that--in analogy to other pathophysiological conditions--c-myc exerts essential regulatory functions in cellular events operative during the initiation and progression of venous bypass graft disease.

Adult↗
PubMed2001

Early clinical experience with the On-X prosthetic heart valve.

BACKGROUND AND AIM OF THE STUDY: The study was designed to investigate the clinical performance of the On-X prosthetic heart valve in a multicenter experience. METHODS: Between September 1996 and September 1999, 301 patients (56% males) underwent isolated On-X valve replacement (184 isolated aortic (AVR), 117 isolated mitral (MVR)) at 11 European centers under a standardized protocol. Average age at implant was 60.2 years. Office or hospital follow up was required by the protocol; average follow up on all patients was 11 months. RESULTS: Thirty-day mortality in the study was 2.2% for AVR and 6.0% for MVR, with valve-related mortality of 0.5% for AVR. There were eight late deaths (0.7%/pt-yr AVR and 2.3%/pt-yr MVR). Two of these deaths were sudden, and thus possibly valve-related (one AVR, one MVR). Early total valve-related morbidity was 3.5% for AVR and 2.6% for MVR. In total, 13 thromboembolic events occurred; one early event in AVR resulted in death (0.5%), and one transient early event occurred in MVR (0.9%). There were 11 late events (seven AVR (1.7%/pt-yr) and four MVR (1.8%/pt-yr)), for a two-year freedom from thromboembolism of 96.6% after AVR and 97.1% after MVR. Three late bleeding events occurred, all after AVR (0.7%/pt-yr and 98.9% free at two years). Major paravalvular leaks requiring reoperation occurred on two occasions early (one AVR (0.5%), one MVR (0.8%)) and once late in MVR (0.5%/pt-yr). Late minor, untreated paravalvular leaks occurred in three AVR patients (0.7%/pt-yr) and in one MVR patient (0.5%/pt-yr). Prosthetic endocarditis occurred four times (two AVR (0.5%/pt-yr), two MVR (0.9%/pt-yr)), all within the first 12 months of surgery. Actuarial freedom from all valve-related events at two years was 88.7% for AVR and 88.1% for MVR. NYHA class was improved in 75.8% of AVR patients and 70.6% of MVR patients at two years after surgery. CONCLUSION: These early results indicate that the On-X valve provides satisfactory clinical outcome in the immediate postoperative period, and that the valve is both safe and effective.

Actuarial Analysis↗
PubMed2001

In vitro investigation of prosthetic heart valves in magnetic resonance imaging: evaluation of potential hazards.

BACKGROUND AND AIM OF THE STUDY: Magnetic resonance (MR) imaging is used in an increasing number of patients, and not only after cardiac valve replacement. However, ferromagnetic biomedical implants are often considered a contraindication for MR imaging because of the potential hazards with respect to their movement, dislodgement, or heating effects during the procedure. The purpose of this study was to assess ferromagnetism, attraction forces, heating effects, and artifacts associated with prosthetic heart valve implants. METHODS: Seventeen common heart valve prostheses (12 mechanical, five biological) were examined in vitro using a high-field-strength 1.5 Tesla (T) MR system. Attractive forces, temperature changes and the amount of artifacts were assessed by applying turbo-spin and gradient-echo sequences. RESULTS: The maximal calculated corresponding ferromagnetic force was (0.22 x 10(-3) N) in the static magnetic field. The temperature changes ranged from 0 to 0.5 degrees C maximum. Artifacts produced by the presence of the heart valve prostheses were less evident using a spin-echo sequence than a gradient-echo sequence. CONCLUSION: MR imaging exerted no significant force on the examined heart valve prostheses, and did not result in significant biological relevant temperature increase. None of the associated artifacts is considered to pose a substantial risk on MR imaging. MR procedures performed with a 1.5 T MR system can be applied safely in patients with heart valve prostheses evaluated in this study.

Artifacts↗
PubMed2001

Aortic valve preservation in acute type A dissection: mid-term results.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the long-term effectiveness of a strategy for managing the aortic valve, aortic root and ascending aorta according to the pathology in acute aortic type A dissection. Results after surgery for acute type A dissection with preservation of the aortic valve were reviewed. METHODS: The patient group included 57 hospital survivors operated on according to a surgical strategy of aortic valve resuspension and supracoronary ascending aortic graft implantation. Reinforcement of the aortic stumps with gelatin-resorcinol-formaldehyde glue was performed in all patients. Aortic valve function in all survivors was investigated by echocardiographic follow up at 30 days, 6 and 12 months after surgery, and yearly thereafter. RESULTS: During the follow up period, nine patients (16%) died without reoperation. Actuarial probability of freedom from reoperation for aortic valve failure in the complete series was estimated as 100% after both 30 days and 12 months. Postoperatively, one patient underwent reoperation 14 months for aortic regurgitation, and three patients for aortic regurgitation with sinus of Valsalva dilatation between 48 and 88 months. The hospital mortality rate at reoperation was 50% (n = 2). CONCLUSION: Valve-sparing surgery is possible and can be recommended for the majority of patients with acute type A aortic dissection.

Actuarial Analysis↗
PubMed2000

Expression of endothelial cell adhesion molecules on heart valves: up-regulation in degeneration as well as acute endocarditis.

Inflammatory cytokines such as interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF-alpha), as well as shear stress, cause endothelial cells (ECs), to undergo not only functional alterations but also structural reorganizations, which contribute to vascular leakage. Like ECs of the human aorta, ECs on heart valves are exposed to extreme shear stress. However, while ECs expression of cell adhesion molecules (CAMs) in large vessels has been widely studied, it seems that there are no such studies on ECs of heart valves, although this knowledge might be important for our understanding of the aetiological aspects of local inflammatory responses. Using immunohistochemistry, this study characterized the CAM expression of ECs on degenerative, mostly calcified heart valves and on heart valves with florid endocarditis. As expected, the constitutively expressed molecules (ICAM-1, CD34, CD31) were found both on degenerative and on inflamed valves. Furthermore, marked expression of E-selectin and VCAM-1 was found not only on inflamed valves, but also on larger portions of the degenerative valves with no morphological evidence of inflammation. This striking finding might help to explain why patients with fibrotic heart valves are susceptible to recurrent endocarditis. Why the endothelial activation markers E-selectin and VCAM-1 are expressed on degenerative heart valves requires further investigation.

Acute Disease↗
PubMed2000

[Aneurysm of the ductus arteriosus Botalli].

A congenital aneurysm of the ductus arteriosus Botalli was detected by chest X-ray as an intrathoracic mass in a 7-day-old infant. Following confirmation of the diagnosis by echocardiography and MRI the aneurysm was successfully resected via left lateral thoracotomy without cardiopulmonary bypass. The postoperative course was uneventful. Six years after operation the patient is asymptomatic and growing normally. An intrathoracic mass may be considered in the differential diagnosis especially in infants and children. Aneurysms of ductus arteriosus potentially are associated with serious complications. Timely diagnosis and early surgical intervention are decisive for prevention of serious complication and death.

Aneurysm↗
PubMed2000

Coronary artery bypass grafting in adult coronary artery disease due to suspected Kawasaki disease in childhood.

Development of coronary artery aneurysms is one typical complication of Kawasaki disease and can cause coronary artery disease even in early childhood. Information about course and outcome in adults is rare. Here, we present a 49-year-old man with serious three-vessel coronary artery disease and giant coronary artery aneurysms following suspected Kawasaki disease.

Coronary Aneurysm↗
PubMed2000

[In vitro investigation of biological and technical prosthetic heart valves using MRI: evaluation of possible deflection and heating of the implants].

PURPOSE: In vitro evaluation of possible deflection and heating of present-day prosthetic heart valves during MR imaging at 1.5 T. METHODS: 17 prosthetic heart valves, 12 technical and 5 biological, were investigated using a 1.5 Tesla Siemens Vision system. Deflection was measured at the edge of a 1.5 Tesla superconducting magnet. Each valve was then submerged in a vial of a 1/1 electrolyte solution and temperature was measured before and after imaging with a turbo-spin-echo sequence (TR 5200 ms, TE 138 ms, Flip angle 180 degrees, acquisition time 10.5 minutes, length of echo train 29). MR imaging was performed with phase encoding parallel and perpendicular to the plane of the valves. RESULTS: None of the investigated prosthetic heart valves were deflected. The maximal observed temperature rise was 0.5 degree C. During MR investigation of the prostheses, artifacts caused by metallic parts were less evident using a spin-echo sequence than a gradient-echo sequence. CONCLUSIONS: Patients with the tested present-day prosthetic heart valves can be safely imaged by MRI.

Bioprosthesis↗
PubMed2000

[Solitary fibrous pleural tumors--rare tumors with unpredictable clinical behavior].

Solitary fibrous tumors of the pleura are rare tumors with unpredictable clinical behaviour. We report about two patients with an incidental finding of an intrathoracic tumor. Preoperative diagnosis was uncertain. In both patients, a solid tumor of the pleura was resected en bloc in combination with a wedge resection of the lung following anterolateral thoracotomy. The postoperative course was eventful. Six months after primary complete resection there were no signs of tumor recurrence.

Diagnosis, Differential↗
PubMed2000

Decalcification of the aortic valve does not prevent early recalcification.

BACKGROUND AND AIM OF THE STUDY: The excellent results with atrioventricular valve reconstruction have stimulated surgeons to attempt reconstruction of calcified aortic valves using decalcifying techniques, but long-term results have been disappointing. The aim of this in vitro study was to evaluate the surface structure of decalcified aortic valve tissue and its potential for recalcification. METHODS: Aortic leaflets were removed from 26 patients with aortic stenosis during elective valve replacement and decalcified by meticulous dissection. Representative specimens were prepared for scanning electron microscopy (SEM) and calcium content in the heavily calcified part of the leaflet in both macroscopically non-calcified and decalcified tissue was determined by atomic absorption spectroscopy (AAS). Additional probes of 'non-calcified' and decalcified tissue were incubated for two and four weeks with medium containing a physiological concentration of calcium to determine their potential for recalcification. As a control, 13 specimens from non-calcified valves were incubated according to the same protocol. RESULTS: All calcified specimens contained high calcium levels (142.70+/-53.76 mg/g). Surgical dissection reduced tissue calcium content significantly (10.04+/-13.43 mg/g). Following two weeks' incubation with calcium, these specimens retained significantly higher levels of calcium (2.88+/-5.17 mg/g) than the 'non-calcified' specimens (19.17+/-7.61 versus 13.49+/-6.27 mg/g; p<0.05); after four weeks similar calcium levels were reached (32.00+/-10.27 versus 28.35+/-9.84 mg/g; p = NS). Non-calcified tissue showed the lowest calcium uptake (4.75+/-4.55 mg/g and 12.29+/-9.43 mg/g at two and four weeks; p<0.05). SEM revealed a loss of endothelial coverage in the calcified areas; decalcification led to an irregular fibrillar surface. Only parts of the macroscopically normal tissue contained endothelial cells, whereas the control tissue showed intact cellular coverage. CONCLUSION: Aortic valve decalcification can effectively remove calcifications, but leaves a fibrillar structure that tends rapidly to accumulate calcium. Even normal-appearing tissue from diseased valves has a higher potential for calcification than normal valvular tissue. These data support the observation of only limited clinical benefits being derived after aortic valve decalcification for aortic stenosis.

Aortic Valve↗