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M Turina

Publications and source records attributed to M Turina.

At least 289 records · Page 16Linked to original sources
PubMed1991

Different activation of the endothelial L-arginine and cyclooxygenase pathway in the human internal mammary artery and saphenous vein.

The endothelium releases substances controlling vascular tone and platelet function. We investigated mediators of endothelium-dependent responses in human internal mammary arteries and saphenous veins. The inhibitor of nitric oxide formation, NG-monomethyl L-arginine, enhanced the sensitivity to norepinephrine (fivefold) and evoked more pronounced endothelium-dependent contractions in internal mammary arteries (19 +/- 6% of 100 mM KCl) than in saphenous veins (2 +/- 1%; p less than 0.005). In internal mammary arteries, NG-monomethyl L-arginine, but not indomethacin, markedly reduced endothelium-dependent relaxations to acetylcholine (from 95 +/- 2% to 39 +/- 7%; p less than 0.005) and prevented those to histamine (78 +/- 6% to 4 +/- 3%; p less than 0.005). In saphenous veins, endothelium-dependent relaxations to acetylcholine were weak (24 +/- 11%), while nitric oxide caused comparable relaxations (85 +/- 3%) as in internal mammary arteries (80 +/- 5%; NS). NG-Monomethyl L-arginine prevented the relaxations to acetylcholine and unmasked endothelium-dependent contractions (30 +/- 10%). Indomethacin and the thromboxane synthetase inhibitor CGS-13080 augmented relaxations of saphenous veins to acetylcholine from 24 +/- 11% to 46 +/- 9% (p less than 0.05). Histamine-evoked contractions were converted to endothelium-dependent relaxations by indomethacin and the thromboxane A2/endoperoxide receptor antagonist SQ-30741 (38 +/- 3% and 40 +/- 6%; p less than 0.05) but not CGS-13080. Thus, 1) nitric oxide mediates endothelium-dependent relaxations in human arteries and veins; 2) internal mammary arteries release more nitric oxide than do saphenous veins, and 3) in saphenous veins, the effects of nitric oxide are reduced by endothelium-derived contracting factors originating from the cyclooxygenase pathway.

Acetylcholine↗
PubMed1991

[Early and late results after surgical treatment of pulmonary atresia with intact ventricular septum].

Between 1970 und 1989 30 children were admitted with the diagnosis of pulmonary atresia with intact ventricular septum (PA/IVS). Before palliation 4 children died. According to the grade of right heart hypoplasia the patients were divided into 3 groups of mild, moderate or severe hypoplasia. Palliative operations were performed in 25 children (17 m, 9 f) with a mean age of 10 days: 13 valvotomies (V), 5 aortopulmonary shunts (S), 7 V plus S. One patient had total correction as primary procedure. A total of 17 reoperations was necessary in 12 of 26 patients (10 palliations, 7 total corrections). Total corrections were: 2 conduits and 5 patches of the right ventricular outflow tract (RVOT). Total mortality was 14/30 (54%) children: early 10/26 (38%), late 4/16 (25%) children. After total correction mortality was 3/7 (43%) children. Actuarial survival after palliation was 46% after 5 and 10 years. For patients with PA/IVS we recommend the following surgical strategy: 1. mild hypoplasia: V plus S for palliation; 2. moderate hypoplasia: S plus patch of RVOT; 3. severe hypoplasia: after initial ballon septostomy S and antegrade decompression of the right ventricle (RV). For total correction in a well developed RV we prefer ASD-closure and patch of RVOT if possible with homograft monocusp. In moderate or severe hypoplasia a Fontan operation is done with closure of the ASD and tricuspid orifice with a single patch.

Cause of Death↗
PubMed1991

[Reduction of postoperative blood loss and donor blood use in heart surgery with aprotinin: experience with various dosages].

The effect of high dose aprotinin was evaluated in a prospective study on 100 patients undergoing cardiopulmonary bypass. Special attention was made on postoperative blood loss and transfusions of bank blood postoperatively. In the first part of the study, after induction of anesthesia, a loading dose of 2,000,000 kallikrein-inhibiting-unit (KIU) = 280 mg aprotinin was given intravenously over a 30-min period. Immediately afterward, a continuous infusion of 500,000 KIU/h was started and maintained until skin closure. Another 2,000,000 KIU was added to the priming volume of the heart-lung machine. A control group of 50 patients was randomized with similar indication for surgery and past cardiac history. The total loss from the thoracic drains was significantly reduced in the aprotinin group as compared with the loss in the control group (490 +/- 265 ml versus 1045 +/- 380 ml). In a separate group of risk patients (redo-operations, infective endocarditis) the total blood loss was even more significant reduced in the aprotinin group (690 +/- 195 ml versus 1585 +/- 290 ml). Patients of the aprotinin group received markedly less bank blood postoperatively (350 +/- 100 ml versus 900 +/- 240 ml without aprotinin). Part II of the study (36 patients) consisted of lower dosage (2,000,000 KIU intravenously during induction of anesthesia only or 2,000,000 KIU in the priming volume of the heart-lung machine only). Patients who received aprotinin in the heart-lung machine only showed no significant difference regarding blood loss and blood requirement to patients with high dose aprotinin. It appears possible that aprotinin reduces the activation of the coagulation during cardiopulmonary bypass and preserves platelet function without affecting platelet consumption during the extracorporeal circulation. The results of our study demonstrate that high dose aprotinin markedly reduces blood loss as well as homologous blood requirement in the early postoperative course of cardiosurgical patients. Similar effects due to reduced aprotinin dose have been observed in patients receiving aprotinin in the extracorporeal circulation only.

Aged↗
PubMed1991

[Preventive cytolytic treatment following heart transplantation: ATG versus OKT3].

The postoperative prophylactic cytolytic therapy with rabbit-ATG and OKT3 after heart transplantation are compared. The first 20 recipients were treated with ATG (5 days), the next 20 with OKT3 (14 days). The medium histological rejection grade (Texas classification) was significantly higher after 2 weeks in ATG group and after 4 weeks in OKT3 group. The linearised rejection rate was 7.1 (ATG) vs. 0.7 (OKT3) (p less than 0.005) at 2 weeks, resp. 3.6 vs. 8.6 (p less than 0.05) and 1.3 vs. 2.9 (p less than 0.005) at 4 weeks and 2 months. After 3 months there was no difference in histological rejection grade (3.6 +/- 1.5 vs. 3.3 +/- 1.7) and linearised rejection rate (2.4 vs. 2.6 per 100 days and patient) between the two groups. Severe rejections are more frequent after OKT3 (6 vs. 11) and probability of rejection free survival is higher after ATG (25% vs. 0%, resp. 21% vs. 0% after 2 resp. 3 months; p less than 0.05). In this study we find no short and medium term benefit of a rejection prophylaxis with OKT3 (14 days) compared with ATG (5 days). Acute allograft rejections in OKT3 group tend to be more severe with a higher mortality.

Antibodies, Monoclonal↗
PubMed1991

[Effect of hemodynamic conditions and prosthesis structure on endothelialization of clinical and experimental small lumen vascular prostheses].

Seeding of small-diameter vascular prostheses (ID less than or equal to 6 mm) with autologous microvascular cells (AMVC) results in a complete endothelial cell layer on the luminal surface. The purpose of this study was to examine the influence of the blood flow velocity (due to 4 or 6 mm ID) and the structure of inner graft surface (crimped, uncrimped) on the endothelialization. AMVC were harvested from omental adipose tissue (mean: 0.56 X 10(6) cells/g tissue) from 10 mongrel dogs (mean: 27.9 kg). During preclotting, the 4 mm uncrimped and the 6 mm crimped double velour Dacron prostheses (Meadox Medicals, Inc.) were seeded with 1.0 X 10(6) cells/cm2 graft surface. Grafts were implanted into the carotid arteries (N = 5 in each group). The animals received antiplatelet therapy. After five weeks, all seeded prostheses were patent. The thrombus free surface (TFS) of seeded prostheses was 99.9% (4 mm) and 90.5% (6 mm). Scanning electron microscopy revealed an athrombogenic layer of endothelial cells on a smooth surface. -It is concluded that in canine experiments endothelialization of 4 and 6 mm grafts after seeding with AMVC is not affected by blood flow velocity or graft structure.

Animals↗
PubMed1991

[Simultaneous coronary and vascular surgery interventions: indications,technique and results].

Atherosclerosis is often a generalized disease, affecting not only coronary circulation, but other parts of vascular system as well. Vascular diseases most commonly encountered in patients with coronary atherosclerosis are carotid disease, abdominal aortic aneurysm and obliterative atherosclerosis in aortoiliac segment. In such situation two options are available: to treat the more significant, life-threatening manifestation first and postpone the other operation--staged approach; or to perform coronary artery bypass grafting (CABG) and other vascular procedures during one single operation--synchronous surgery. The advantages of this latter approach are obvious: patient has to undergo only one operation; there is no additional risk in the waiting period for second operation; surgical treatment is greatly accelerated. From 1978 until July 1990 a total of 123 synchronous CABG and vascular procedures were carried out in our clinic. In the same period, CABG was performed in 3867 pts in the same institution; combined procedures amount to 3.5% of all coronary revascularisations performed in the same period. CABG was done together with carotid endarterectomy (CEA) in 45 pts, associated with resection of abdominal aortic aneurysm (AAA) in 31 and in 28 pts it was combined with vascular procedures in aorto-iliac or femoral segment. In 4 pts a triple procedure--CABG, CEA and peripheral vascular reconstruction--were undertaken. Thoracic aortic aneurysm and CABG were performed in 15 pts. CEA is performed immediately prior to CABG in symptomatic carotid disease, past history of transient ischemic attack, severe bilateral carotid disease and unilateral carotid obstruction with contralateral stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Aneurysm↗
PubMed1991

[Simultaneous revascularization of the renal arteries in conjunction with reconstruction of aneurysms of the abdominal aorta].

Simultaneous revascularization of stenosed renal arteries during resection of aneurysms of the abdominal aorta was performed in a consecutive series of 30 patients (mean age: 65 +/- 7 years; men 27 [90%]; women 3 [10%]). Right renal artery was operated upon in 20/30 cases (66%) and left renal artery in 15/30 cases (50%) for a mean degree of stenosis of 79 +/- 19%. Suprarenal extension of the aneurysm of the abdominal aorta was observed in 7/30 cases (23%). Emergency operation because of rupture of the aneurysm was necessary in 7/30 cases (23%). The following procedures were performed upon the renal arteries, either isolated or combined, in addition to resection of the aneurysm of the abdominal aorta: reimplantation of the renal artery in 15 cases, thrombendarteriectomy of the renal artery in 11 cases, patchangioplasty in 8 cases, bypass in 4 cases, dilatation in 1 case, autotransplantation in 1 case. The 30-day mortality was 1/23 (4%) for elective procedures versus 3/7 (43%) for emergency procedures (ruptures). Systolic (diastolic) blood pressure dropped from a preoperative mean value of 181 +/- 139 (104 +/- 18) mm Hg to a postoperative mean value of 147 +/- 18 (80 +/- 18) mm Hg: p less than 0.05 (p less than 0.05). Hence, simultaneous revascularization of stenosed renal arteries during resection of aneurysms of the abdominal aorta helps not only to salvage renal parenchyma but also to control the risk factor hypertonia in a significant number of patients.

Adult↗
PubMed1991

[Blood transfusion and reducing the need for blood in heart transplantation].

Viral infections transmitted by the donor organ or by blood and blood products are severe complications in heart transplantation. The use of blood and blood saving management is evaluated in 57 consecutive orthotopic heart transplantations. Indication was cardiomyopathy in 63%, coronary artery disease in 30%, valve disease in 5%, congenital in 5%, arrhythmia in 5% and primary cardiac malignancy in 2%. Previous open heart surgery was performed in 32%, and 81% had anticoagulation, with a mean quick value of 0.28 +/- 0.13. The total use of blood and blood products was 1151 units and was distributed as follows: whole blood and packed cells 41%, platelets 17%, fresh frozen plasma (FFP) and coagulation factors 36%, albumine 7%. Anticoagulated recipients received more FFP and factors, 7.9 +/- 5.7 U vs. 4.4 +/- 4.8 U. In the reoperation group 78% vs. 22% (p less than 0.001) in the primary operation group received platelets. Hemodilution to hematocrit 0.24 instead of 0.30 lead to a decrease of red cell transfusions per patient from 12.3 +/- 6.7 U to 6.3 +/- 7.4 U (p less than 0.001) and the percentage of patients receiving red cells was reduced from 100% to 82%. Intraoperative hemofiltration was performed in 49% (mean filtration volume was 1652 +/- 910 ml). No differences in the amount of blood and blood products could be shown. Heart transplantation is an operation with a high need for blood and blood products. Reoperation and anticoagulation are predictors for a higher use of platelets, FFP and coagulation factors. Hemodilution reduces the use of red cells, whereas intraoperative hemofiltration has no influence on the use of blood.

Adolescent↗
PubMed1991

[Aortic isthmus stenosis: a comparison of resorbable and non-resorb able sutures].

Absorbing vessel suture material presents the particular advantage of unlimited growth potential of young vessels. This is due to low tissue irritation and only a minimum of foreign-body reaction of the tissue. Retrospectively, we compared 9 patients (5 +/- 3 years of age), who underwent resection of the coarctation and end-to-end reanastomosis, with absorbing simple continuous suture material versus 8 patients (7 +/- 5 years of age; NS) with non-absorbing suture material using a prolong-thread suture technique, who were operated between 1980 and 1986. The growth increase before to 4 years after operation (24 +/- 10% in the "absorbing suture group-A" and 36 +/- 27% in the "non-absorbing suture group-B"; NS) just as the pressure gradient (55 +/- 11 mm Hg in group A, 58 +/- 16 mm Hg in group B (NS) before and 6 +/- 8 mm Hg in group A, 5 +/- 9 mm Hg in group B (NS) 4 years after operation) shows no significant difference. Therefore one may say that absorbing material in simple continuous suture technique presents a good alternative to the non-absorbing material in the prolonged-thread suture technique for correction of aortic isthmus stenosis, whereby analogous growth can be expected.

Anastomosis, Surgical↗
PubMed1991

[Surgery of extracranial aneurysms of the carotid artery. Analysis of 8 cases].

This article reviews the clinical manifestations, operative techniques, results and complications associated with the treatment of 8 aneurysms of the extracranial carotid artery encountered over a 13-year period. The etiology was atherosclerosis in 4 cases, congenital in two, posttraumatic in one and mycotic in another case. All patients were operated on because of symptomatic disease. Six patients had resection and reconstruction with end-to-end anastomosis, one with a patch of the saphenous vein. One patient had aneurysmorrhaphy and the last one had reconstruction with Gore Tex graft interposition. Two patients had a hemiparesis prior to the operation; this manifestation disappeared slowly in both patients but residual neurological deficit is still present in one of them 9 months postoperatively. One patient developed transient neurological symptomatology after the operation. We conclude that accessible aneurysms of the extracranial carotid artery can be operated with acceptable morbidity and mortality. Operative management is the treatment of choice because these lesions are attended by a high incidence of neurological complications if left untreated.

Adolescent↗
PubMed1991

[Conservative surgery of congenital isolated mitral valve anomalies in children. Early and late results].

Conservative surgery for non-av-canal mitral valve anomalies was performed in 30 children under 15 years of age between 1965 and 1986 at our institution. In 14/30 (47%) children these anomalies were isolated (without other intra- or extracardiac defects). Mean age of the 14 children was 6.7 years (range 9 months to 15 years). Preoperatively mitral insufficiency was found in 12 cases, stenosis in one and combined insufficiency and stenosis in one case. The following morphological substrates of mitral valve were found: annular dilation 3, leaflet anomalies 20, chordal anomalies 4, papillary muscle anomaly 1. Surgical technique was as follows: annuloplasty 9, plication of leaflet 4, closure of cleft 10, commissurotomy 2, displacement of papillary muscle 1. Early mortality was 1/14 (7%) patients. There was no death during a mean follow-up interval of 14.8 years (range 30 days to 25 years). Actuarial survival was 93% after 10 and 15 years (95% confidence limits 78-100%). A total of 2 reoperations was necessary (delay 16 day and 46 months). In both cases valve replacement was performed (valve size 27 and 29 mm). Actuarial reoperation-free interval was 77% after 10 and 15 years (95% confidence limits 53-100%). In conclusion conservative surgery for isolated mitral valve disease gives good long-term results. When reoperation is necessary, adult-sized prosthesis can be implanted. Conservative surgery is the procedure of choice for congenital mitral valve disease.

Actuarial Analysis↗
PubMed1991

[Peritoneal dialysis in treatment of postoperative heart failure after correction of complex heart defects in young children and infants].

Low cardiac output can be encountered after corrective surgery for complex congenital malformation in children and infants and is often accompanied by an impairment of renal function, ascites, hyperosmolarity and hyperpyrexia. In most instances, combined afterload-reduction and inotropic stimulation will be effective. If low cardiac output persists, a peritonealdialysis (PD) may allow correction of fluid balance and consecutive improvement of hemodynamics. During a 18 month-period, PD was performed in 14 children in the postoperative period following major cardiac surgery (transposition 5, Fallot tetralogy 5, various complex anomalies 4). This represents 3.1% of all cardiac operations performed in children with congenital heart disease throughout the same period. There were 8 males and 6 females with a median age of 2.5 years (range 3 days to 4 years) and a median bodyweight of 5.5 kg (range 3.4 to 10 kg). Low cardiac output was defined when two or more of the following factors were met: mean arterial pressure (MAP) below 40 mm Hg despite inotropic stimulation, central venous pressure (CVP) over 15 mm Hg, urine production less than 1 ml/kg/hour and/or increasing transaminases. Before starting peritoneal dialysis all children received combined positive inotropic and vasodilative therapy. The PD-catheter was introduced 8 to 30 hours after operation. We used a PD-solution with 1.5% and/or 4.5% glucose. Fluid balance was monitored hourly. Just after introduction of the catheter a mean of 65 ml +/- 25 ml/kg ascites could be removed and the total quantity of removed fluid was 175 ml +/- 45 ml/kg bodyweight.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1991

[Rest ventricular function in left heart bypass].

During partial left heart bypass (LHBP), the flow delivered by an assist device is easy to measure while residual left ventricular function (LVI) seems difficult to assess. In this study, we have attempted to define the separate right and left ventricular function during LHBP. In 6 anesthetized dogs, following thoracotomy and systemic heparinization, aorta and left atrium were cannulated and connected to the servo-controlled roller pump (modified Stöckert-System). Following saline infusion (30 ml/kg), LHBP was started and maintained at 50 ml/min/kg throughout 6 h. Standard hemodynamic parameters were continuously monitored. Cardiac output, blood gas analyses, hemoglobin and activated coagulation time were measured at regular intervals. LVI was calculated as the difference between cardiac output and assist-flow rate. Other derived variables were obtained using standard formulas. The Wilcoxon rank-test was used for the statistical analysis. The results, as median and 25th-75th percentile, are summarized in the graphics 1-6. Under the experimental conditions of this study, the flow performance and stroke work of the right ventricle remained unchanged, while the work-unloaded left ventricle maintained only a part of systemic perfusion. Neglecting the physiological shunt and its changes, which influences the difference between the left and right ventricular output, the simple formula to assess LVI during LHBP seems plausible.

Animals↗
PubMed1991

[Mechanical circulatory assist using a miniaturized Archimedes screw].

An axial flow blood pump (Archimedes screw) for intraarterial left ventricular assist was evaluated in comparison to standard roller pump left heart bypass (LHBP) in 13 bovine experiments (bodyweight 74 +/- 15 kg). Full systemic heparinization (ACT greater than 500 s) was used for LHBP in comparison to limited systemic heparinization (ACT greater than 180 s) for axial. A standard battery of blood samples was taken before and at regular intervals throughout perfusion: (table; see text) Transarterial access and relatively limited blood trauma appear to be the main advantages of the evaluated axial flow blood pump. However, the impossibility to assess the pump flow may be a major problem for the management of the failing left ventricle.

Animals↗