Search PubMed⌕ Search

Biomedical subjects

H Oelert

Publications and source records attributed to H Oelert.

At least 145 records · Page 8Linked to original sources
PubMed1989

Influence of incremental preoperative risk factors on the perioperative outcome of patients undergoing emergency versus urgent coronary artery bypass grafting.

A retrospective analysis of 127 patients with impending myocardial infarction undergoing coronary artery bypass grafting was performed to evaluate incremental risk factors associated with perioperative mortality and morbidity. Fifty-four patients (group 1) were operated upon as emergencies within 24 h and 73 patients underwent urgent coronary revascularization within a mean of 3.4 days (group II) after admission. The incidence of non-transmural myocardial infarctions (NTMI), haemodynamic parameters, the number of diseased vessels and the incidence of a preceding percutaneous coronary dilatation (PTCA) were not statistically different between the groups. The overall perioperative mortality was 8.7% (16.7% group I, 2.7% group II). Major non-fatal complications were frequent in the surviving collective including low cardiac output in 14 patients (12.1%) and transmural or subendocardial perioperative infarction in 12 patients (10.3%). Perioperative mortality was associated with reduced left ventricular myocardial function (P less than 0.001), operation within 24 hr after onset of anginal symptoms (P less than 0.001) or subendocardial infarction (P less than 0.025) in the 4 weeks before operation. Perioperative mortality was independent of the degree of coronary stenosis, number of distal anastomoses or performance of a coronary endarterectomy. Of the patients, 90.5% (87.5% of group I and 92.3% of group II) included in a mean follow-up of 16.8 months (range 5-27 months) were graded into Canadian Heart Functional Class I. Successful coronary surgery for acute myocardial ischaemia results in excellent late functional recovery. The major risk factors for fatal perioperative outcome are reduced left ventricular function and the necessity of every early surgical intervention.

Angioplasty, Balloon, Coronary↗
PubMed1989

Emergency surgical revascularization following coronary angioplasty: evaluation of operative results by isoenzyme analysis and electrocardiography.

Seventeen patients underwent emergency coronary artery bypass grafting due to balloon catheter induced occlusion or dissection of a major coronary artery. Patients were revascularized within a maximum of 210 min from the onset of ischaemia and received an average of 1.6 distal anastomoses. A perioperative transmural or non-transmural myocardial infarction as diagnosed by CK-MB activity and electrocardiographic patterns occurred in 7 patients (41.2%). One early death resulted in an overall perioperative mortality of 5.9%. Successful preservation of myocardium was demonstrated in 10 patients by a rapid decline of CK-MB activity, no perioperative electrocardiographic changes and no requirement for inotropic support. The incidence of a perioperative myocardial infarction was independent of the anginal status before coronary angioplasty or the angiographic evidence of a complete occlusion versus a dissection. Major ischaemic myocardial complications associated with coronary angioplasty are rare but frequently catastrophic events. Fast surgical intervention is mandatory to prevent myocardial infarction or to limit the extent of injury. The operative outcome can be evaluated by careful analysis of time release curves and cumulative parameters of CK-MB activity.

Adult↗
PubMed1989

Anatomically corrected malposition of the great arteries, inflow ventricular septal defect, and subaortic stenosis: diagnostic and operative implications.

Intracardiac correction of the combination of rare congenital heart lesion of anatomically corrected malposition of the great arteries, severe muscular as well as fibrous subaortic stenosis, and ventricular septal defects in the inflow and the trabecular septum in a 2 1/2 years old boy is reported. There was an additional large secundum atrial septal defect. The operation consisted of resection of the subaortic stenosis by a combined transatrial and transaortic approach, thereby regaining a wide outflow tract of the systemic ventricle. Both the ventricular and atrial septal defects were closed with Dacron patches. Reinvestigation 10 days after the operation revealed a residual pressure gradient across the outflow of the systemic ventricle of less than 10 mmHg. A secondary ventricular septal defect was detected in the anterior muscular septum at the same time and closed with a patch in a reintervention. At discharge from the hospital two weeks later the child was in excellent condition and had a stable sinus rhythm. The preoperative differential diagnosis of a double outlet right ventricle with L-malposition of the aorta as well as possible surgical approaches are discussed.

Angiocardiography↗
PubMed1989

Functional role of cholinoceptors and purinoceptors in human isolated atrial and ventricular heart muscle.

1. The effects of cholinergic and purinergic stimulation on action potential, force of contraction and 86Rb efflux were investigated in human atrial and ventricular heart muscle. 2. In atrial heart muscle, carbachol and (-)-N6-(R-phenyl-isopropyl)-adenosine (R-PIA) and 5'-(N-ethyl)-carboxamido-adenosine (NECA) evoked transient decreases of action potential duration and force of contraction; the steady-state effects on force of contraction were virtually identical to control values. In the presence of propranolol, steady-state values after carbachol, R-PIA or NECA amounted to about 50% of control values. 3. In ventricular heart muscle, carbachol, NECA and R-PIA did not significantly affect the action potential configuration or force of contraction. 4. Carbachol, NECA and R-PIA induced a maintained depression of the positive inotropic response to isoprenaline in both atrial and ventricular heart muscle. 5. The rate constant of 86Rb efflux was slightly increased by carbachol, NECA and R-PIA in atrial (10-20%) but not in ventricular heart muscle. 6. In the presence of isoprenaline, carbachol, NECA and R-PIA did not significantly affect the rate constant of 86Rb efflux in both atrial and ventricular heart muscle. Isoprenaline alone increased the rate constant of 86Rb by about 25% in both tissues.

Action Potentials↗
PubMed1989

Ambulatory follow-up of aortic dissection by transesophageal two-dimensional and color-coded Doppler echocardiography.

Follow-up of 18 patients with aortic dissection (five with type I, one with type II, 11 with type III dissection according to DeBakey) by transesophageal, two-dimensional and color-coded Doppler echocardiography showed a persistence of the false lumen in five of seven patients (71%) after surgery and in nine of 11 patients (82%) after medical therapy. In two patients treated with surgery, the dissected part of the aorta had been resected, whereas in two patients treated medically, a progressive and complete obliteration of the false lumen was observed. In the false lumen, thrombus formation was absent in four, localized in four, and progressive in six patients. Flow within the false lumen could be registered in 14 patients, and two distinct flow patterns were differentiated (laminar biphasic flow or slowly circulating flow). Persisting intimal tears were visualized by two-dimensional echocardiography in four patients, whereas color-coded Doppler showed an additional one to three intimal tears in the descending aorta in 10 patients. Flow across these intimal tears was biphasic in 75% of patients; that is, systolic flow was directed from the true to the false lumen with diastolic flow reversal. Unidirectional flow was detected in 25% of the communications, directed in 20% from the true to the false lumen, serving as an entry only and in one (5%) as reentry only. Additional information concerning complications like extension of the dissection (one of 18 patients), localized dilatation of the regurgitation (three of 18 patients) were detected by this method. Concerning the morphologic findings and the detection of flow characteristics, the transesophageal approach was superior to conventional echocardiography especially in the descending thoracic aorta. Thus, transesophageal two-dimensional and color-coded Doppler echocardiography seems to be an ideal method not only for the easy detection of aortic dissection but also for follow-up.

Adult↗
PubMed1989

Urgent indications for surgery in primary or secondary cardiac neoplasm.

Ten patients underwent resection of primary or secondary cardiac tumor. Two-dimensional transthoracic echocardiography per se accurately located the endoluminal cardiac mass in nine patients, and transesophageal echocardiography demonstrated a right atrial tumor in the tenth case. The indications for urgent surgery included prior embolic events (3 cases), syncopal attacks (2) or echocardiographic evidence of a multilobulated mass (2 cases). The operative strategy was standardized for atrial tumors, but for malignant myocardial neoplasm both the anatomic site and the extent of tumor growth determined the surgical procedure. Histologic examination showed myxoma in seven cases, fibroma in one and metastases of malignant melanoma in two cases. The course after resection of endoluminal benign tumor was uneventful apart from transient atrial fibrillation in four cases. Follow-up echocardiography (after 4-28 months) showed no recurrent growth. In both cases of intracardiac metastases there was recurrence within 6 to 8 months after resection of the growth.

Adult↗
PubMed1989

Initial clinical experience with an endoluminal spiral prosthesis for treating complicated venous thrombosis and preventing pulmonary embolism.

Fourteen patients with complicated venous thrombosis or recurrent pulmonary embolism were treated by implantation of an endoluminal spiral prosthesis subsequent to balloon angioplasty, surgical thrombectomy or embolectomy, a combination of these, or, in 2 cases, no other treatment. The patients were divided into 2 groups, based on their primary diagnosis and the purpose of the prosthesis. Group I included 8 patients with extensive iliofemoral or caval thrombosis, caused by congenital caval stenosis (1 case) or extravascular compression or retraction (7 cases); 7 of these patients had had previous operations, and the remaining patient had undergone thrombolysis, which failed. The current treatment consisted of balloon angioplasty and surgical thrombectomy or embolectomy, and implantation of an endoluminal spiral stent to prevent elastic recoil of the vessel. In 4 cases, an arteriovenous fistula was constructed and was taken down 3 months later; in 1 additional patient, a bilateral arteriovenous fistula was created. Group II comprised 6 patients with recurrent pulmonary embolism (4 cases), massive pulmonary embolism (1 case), or paradoxical bilateral carotid artery embolism (1 case). Four of these patients underwent surgical thrombectomy or embolectomy, while 2 had no treatment other than filter implantation. All 6 underwent transluminal implantation of a helix caval filter (a modification of the endoluminal spiral stent). All but 1 implantation was accomplished by means of either a transfemoral or a transjugular cutdown; the remaining implantation was performed transatrially after a pulmonary embolectomy. The only device-related complication was a retroperitoneal hematoma in Group I, resulting from perforation of the inferior vena cava by the guidewire during device implantation. This complication necessitated an emergency laparotomy and takedown of the arteriovenous fistula, which resulted in rethrombosis of the left iliofemoral vein. The other 7 stented veins were patent at early phlebographic follow-up, as were all 5 of those studied later. One Group-I patient died 4 months after surgery, due to tumor progression and without signs of caval restenosis. Twelve months postoperatively, 1 Group-II patient died of urosepsis without a recurrence of pulmonary embolism. Four of the 6 Group-II patients were studied late postoperatively, and all of their stented vessels were patent. There was no operative mortality or postoperative embolism. On the basis of these results, we conclude that endoluminal stenting with an expandable spiral prosthesis is a promising method for remote venous reconstruction. Moreover, it appears that the modified stent, or helix caval filter, compares favorably with commercially available filters.

Journal Article↗
PubMed1989

Concentrations of some trace elements (Se, Zn, Cu, Fe, Mg, K) in blood and heart tissue of patients with coronary heart disease.

We measured Se, Zn, Fe, Cu, Mg, and K in blood and heart tissue of patients with coronary heart disease. Such patients have subnormal selenium concentrations in serum, whole blood, and (calculated per gram of hemoglobin) erythrocytes. Concentrations of zinc and copper in serum were also subnormal in these patients. Heart tissue collected from these patients during bypass surgery was analyzed for Se, Zn, Fe, Cu, Mg, and K; results are expressed in terms of wet weight and in relation to nitrogen and phosphorus content. Concentrations of these elements in blood are correlated with those in heart tissue. Selenium concentrations in serum correlated positively with those in tissue but not with those in erythrocytes. We found no association between concentrations of zinc, iron, copper, magnesium, and potassium in serum and the corresponding concentrations in heart tissue. There was a moderately positive correlation between the concentration of ferritin in serum and that of iron in tissue. We conclude that the turnover rate for selenium in tissue is similar to that in serum but greater than that for erythrocyte selenium. The concentrations of these six elements in heart tissue are partly correlated with the ejection fraction of the left ventricle.

Copper↗
PubMed1989

[The 4 mm plasma-tetrafluoroethylene prosthesis as a coronary vessel replacement in the animal experiment].

For coronary artery revascularisation the availibility of a prosthesis may be useful, which in case of insufficient or inadequate veins may be used as a biocompatible substitute. The new 4 mm Plasma TFE prosthesis consisting of a woven fiber of polyethylenteraphtalate (PET) coated with an ultrathin layer of Tetrafluoroethylene (TFE) has shown to be highly non thrombogenic in vitro and was therefore regarded as being promising. In an experimental study 10 beagle dogs underwent aortocoronary bypass grafting in order to evaluate the in vivo behavior of the prosthesis. In group 15 dogs received a Plasma TFE prosthesis of 7 cm length. To overcome the problems of inadequate caliber at the distal side of the anastomosis another 5 dogs in group II received a composite sequential graft composed of a 4 cm proximal Plasma TFE prosthesis and a 3 cm distal autologous saphenous vein. Treatment with antiplatelet drugs (Aspirin) was started during the operation and continued by daily doses of 500 mg p. os. Control-angiography 1 week after the operation demonstrated patency of 1 out of 5 grafts in group I and 4 out of 5 grafts in group II. Half a year later the only graft from group I was still patent, whereas in group II all grafts had thrombosed. Histological examinations showed the graft coated with a layer of 50-250 microns fibrous tissue mear the aortic anastomosis, while more distally the prosthesis was completely occluded. In conclusion the 4 mm Plasma TFE prosthesis though promising from in vitro experiments has proven to be not suitable as a substitute for aortocoronary artery bypass grafting in the dog.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

[Supravalvular pulmonary stenosis following anatomic correction of transposition of great vessels: report of a successful balloon dilatation].

Primary anatomical repair of TGA has several theoretical advantages over conventional atrial baffle techniques. However, one of the most common postoperative complications of the new technique is the development of an obstruction at the arterial anastomosis to the pulmonary artery (PA). A supravalvular pulmonary stenosis developed progressively over the first months after an arterial switch operation of a simple TGA in a newborn infant. The diagnosis was easily performed by Doppler-echocardiographic follow-up studies. Hemodynamic assessment by cardiac catheterization performed when the patient was five months old revealed a systolic gradient of 76 mm Hg at the arterial anastomosis. Percutaneous balloon angioplasty was successfully performed.

Catheterization↗
PubMed1988

Improved diagnostic value of echocardiography in patients with infective endocarditis by transoesophageal approach. A prospective study.

In a prospective study, the clinical value of transoesophageal two-dimensional echocardiography (TOE) as compared with transthoracic two-dimensional echocardiography (TTE) was determined in patients with suspected infective endocarditis. Ninety-six patients were studied consecutively with an electronic sector scanner using 2.25 and 3.5 MHz probes for TTE and a 3.5 MHz probe embedded in tip of a flexible 12 mm gastroscope for TOE. Results of surgery and autopsy were available for 20 of the 96 patients with infective endocarditis and echocardiographically demonstrated vegetations and 70 control patients with valvular heart disease without infective endocarditis and no signs of vegetations, who were studied preoperatively with TTE and TOE. For TTE and TOE, the measured sensitivity was 63% and 100%, specificity 98% and 98%, positive predictive accuracy 92% and 95%, and negative predictive accuracy 91% and 100%, respectively. In 39 patients who had positive blood cultures, vegetations were found by TOE in 32 patients (82%), but in only 27 patients (69%) by TTE. Image quality was the main factor contributing to the superiority of TOE over TTE: it was reduced in 11/20 patients (55%) in whom vegetations were not detected by TTE. Another important factor was the size of vegetations. Only 6/24 vegetations (25%) of less than 5 mm but 9/13 vegetations of 6-10 mm, and 14/14 vegetations of greater than 11 mm detected by TOE were also observed with TTE. The clinical importance of detecting vegetations was demonstrated by the rate of embolism. In patients with vegetations embolism was 25% when blood cultures were positive and 21% when they were negative. In patients without echocardiographically detectable vegetations signs of embolism were seen in no patient with positive and 7% of the patients with negative blood cultures. Evidence of vegetations was found on the aortic valve in 14 patients and on the mitral valve in seven patients in whom valvular incompetence was not present, indicating that the valve had not yet been damaged significantly. TOE is superior to TTE in detecting vegetations in suspected infective endocarditis because of better image quality, particularly when vegetations are small. TOE seems to be indicated in patients with suspected endocarditis and reduced image quality or negative TTE results. Early detection of vegetations on valves may help confirm the diagnosis of infective endocarditis at an early stage and hopefully lead to an improved prognosis by reducing delay in instituting appropriate therapy.

Echocardiography↗