Volker Schlosser

Determination of aortic valve orifice area in aortic valve stenosis by two-dimensional transesophageal echocardiography

Two-dimensional transesophageal echocardiography was used to measure aortic valve orifice area in 24 patients with aortic valve stenosis (AS) and 15 patients without aortic valve disease. Using transesophageal echocardiography, orifice area could be measured in 20 of 24 patients with AS. With transthoracic echocardiography, orifice area could be determined in only 2 of 24 patients. In patients with AS, orifice area determined by transesophageal echocardiography was 0.75 +/- 0.34 cm2 and that calculated with Gorlins formula was 0.75 +/- 0.32 cm2. In normal aortic valves, orifice area was 3.9 +/- 1.2 cm2 by transesophageal echocardiography. A good correlation was demonstrated between aortic valve orifice area determined using transesophageal echocardiography and calculated orifice area using Gorlins formula in patients with AS: r = 0.92, standard error of estimate = 0.14 cm2. The absolute difference between orifice area measured with both methods ranged from 0.0 to 0.4 cm2 (mean 0.09 +/- 0.1). In 4 patients orifice area could not be determined with transesophageal echocardiography. The orifice could not be identified in 2 patients because an appropriate cross-sectional view of the aortic valve could not be achieved and in 2 patients with pinhole stenosis (aortic valve orifice area 0.3 cm2). These data show that aortic valve orifice area can be measured reliably using 2-dimensional transesophageal echocardiography.

Transcranial Doppler ultrasonography during cardiopulmonary bypass in patients with severe carotid stenosis or occlusion.

Blood flow velocity of the middle cerebral artery was monitored during cardiopulmonary bypass procedures by means of transcranial Doppler ultrasonography. Our investigation was carried out in a group of 16 patients with severe carotid stenosis or occlusion and in a control group of 42 patients with no or stenosis of less than 50% local diameter reduction. After onset of cardiopulmonary bypass, both groups showed a short unstable phase followed by increased blood flow velocity (10% increase ipsilateral to the obstruction, 27% increase in the control group). Just before rewarming, blood flow velocity was still comparable to (control group -3%) or higher than (ipsilateral to obstructions +14%) prebypass values. Analysis of three patients with postoperative diffuse encephalopathy did not reveal reduced blood flow during cardiopulmonary bypass as a relevant factor. Two of the three showed luxury perfusion. Reduced perfusion due to carotid obstruction was not observed during cardiopulmonary bypass and therefore cannot be considered a significant risk factor for the development of intraoperative stroke.

Multiple Venous Aneurysms of the Saphenous Vein: Report of an Uncommon Case

Venous aneurysms are rare entities. They may cause serious complications like thrombosis or pulmonary embolism. An uncommon case of multiple large aneurysms of the saphenous vein of a forty-one-year old woman is reported. The literature is reviewed and etiology, potential complications, diagnosis, and treat ment are discussed.

Acute surgical intervention for complications of percutaneous transluminal angioplasty

Since 1979, percutaneous transluminal angioplasty (PTA) resulting in an overall improvement of 80.3% has been performed in 4380 patients with occlusive atheroma of the lower extremities. Complications requiring immediate surgical treatment occurred in 123 (2.8%) of the cases, consisting of occlusion (16%), dissection (13%), perforation (10%), embolisation (15%) and haematoma at the puncture track (69%). Of the group treated surgically, 18 (14.6%) patients underwent amputation of a lower limb. Since 1980 348 percutaneous transluminal coronary angioplasties (PTCAs) have been performed for coronary artery disease. In 15 cases (4.3%) emergency coronary bypass surgery was necessary because of complications encountered with PTCA. Two patients died and perioperative myocardial infarction occurred in 7 (subendocardial-3: transmural-4). In spite of a low complication rate and good results from PTA and PCTA acute surgical intervention for complications carries a significant operative morbidity and mortality. We conclude that selection for PTA and PTCA has to involve vascular and cardiac surgeons, their presence being mandatory at institutions in which therapeutic radiological procedures are undertaken.

Cystic adventitial degeneration as a cause of dynamic stenosis of the popliteal artery: a case report.

Cystic adventitial degeneration, which is generally localized in the popliteal artery, leads to a dynamic, exercise-dependent flow inhibition. The cysts of the adventitia, which increase in size with exercise, cause an increasing degree of stenosis which can be completely reversed after a longer period if rest. Angio graphic presentation may therefore be misleading. Functional examination with Doppler sonography is able to identify the obstruction in such cases. Resection of the involved vessel and restoration of flow by interposition of a vein graft is the therapy of first choice.

Prophylaxis Against Thromboembolism in Vascular Surgery (A Randomised Clinical Trial)

Thrombosis prophylaxis is indicated in vascular surgical patients for two general considerations: to prevent thromboembolism from the venous system and occlusion of reconstructed arterial vessels. The purpose of this randomized, prospective study was to compare the effectiveness of low-dose heparin, heparin in combination with dihyder gotamine, and dextran-60 in the prevention of postoperative venous throm bosis and pulmonary embolism after vascular operations. In addition, any adverse effects of each medication on patency after arterial reconstruction was to be determined.

Nifedipine inhibits granulocyte activation during cardiopulmonary bypass.

Two groups of patients were investigated. Group 1 consisted of 6 patients (4 female, 2 male) with a mean age of 36.8_+9.1 years and group II of 7 male patients (56.3 _+ 1.7 years). Patients of group II received a continuous infusion of nifedipine (5.91 ±0.53 gg/kg of body weight/h) 15 min before the begin of the extracorporeal circulation till the end. Patients of group I acted as controls. Heparinized blood samples were taken as indicated. Plasma levels of C3a and granulocyte elastase in complex with cq-proteinase inhibitor (E-cq PI) were determined as previously described [31.

Open-Heart Surgery in Jehovahs Witnesses

Efforts to reduce blood loss and subsequent donor blood transfusions have gained increasing importance in open-heart surgery over the last few years [1, 2, 4, 8, 16].

Computerised tomography after abdominal aortic aneurysm repair

CT scan early after AAA resection and graft implantation enables the detection of local complications such as extensive haematomas around the implanted graft (25 cases), gas bubbles (7 cases) fluid collections, inflammatory infiltration in the tissue around the graft and compression of organs in the neighbourhood (1 case) to be detected. The possibility of detecting these complications as early as possible allows effective treatment. The addition of CT guided needle biopsy to allow culture of suspicious material makes this a very useful technique. For these reasons routine postoperative CT scanning after aortic aneurysm surgery is recommended.

Release of Granulocyte Proteins During Cardiopulmonary Bypass: Effect of Different Pharmacological Interventions

Leukopenia and anaphylatoxin formation occur during cardiopulmonary bypass1,2. Both C3a and C5a are converted to their respective desArg forms by plasma carboxypeptidase, but C5a-desArg still retains its capacity to activate leukocytes2-6. After C5 cleavage C5b-9 complexes are generated on target membranes or SC5b-9 complexes in the fluid phase. Recent studies demonstrated deposition of C5b-9 on blood cells during cardiopulmonary bypass. It was suggested that C5b-9 complexes may be partly responsible for the hemolysis and may augment granulocyte activation by the stimulation of arachidonate metabolism in those cells7.