Desaturation and esterification of fatty acids in kidney cells from spontaneously hypertensive rats.

In previous studies, several alterations in lipid metabolism have been related to hypertension, but the mechanisms explaining this relationship have not been elucidated. None of the previous works has focused on the lipid metabolism in kidney, which is a key organ in the overall regulation of blood pressure. The aim of the present work was to study the metabolism of polyunsaturated fatty acids, and the possible compositional changes in kidney from hypertensive rats. Radiolabelled linoleic acid (18:2,n-6) and dihomogammalinolenic acid (20:3, n-6) were incubated with isolated kidney cells from spontaneously hypertensive rats (SHR) or the parent normotensive strain (Wistar Kyoto, WKY). The rats were divided into groups of age 9 (young) and 17 (adult) weeks. Cellular uptake, desaturation, chain-elongation, oxidation and distribution into phospholipids and triacylglycerols were measured. Additionally, the lipid composition of kidney was characterized. With each of the labelled fatty acid substrates the uptake in cells from the SHR rats, compared to the WKY rats, was numerically lower in the young group and higher in the adult group. The incorporation of labelled fatty acids into phospholipids was increased and concomitantly decreased in triacylglycerols in cells from adult SHR rats. The delta6-desaturation, measured as the conversion of labelled 18:2(n-6) to 18:3(n-6) was between two and three times increased in cells from the adult rats compared to the young ones, while no difference was found in hypertensives compared to normotensives. Concomitantly, no difference in conversion of labelled 20:3(n-6) to 20:4(n-6) was observed in relation to blood pressure, but, different from delta6-desaturation, the delta5-desaturation was significantly decreased by age. Taken together, this study demonstrates for the first time desaturation of long-chain polyunsaturated fatty acids in isolated kidney cells in suspension and that, contrary to what has been observed in liver, the desaturase activity is unaffected by hypertension. Also different from what has been observed in liver, no blood-pressure-related changes in lipid composition of kidney were found.

[Tetralogy of Fallot. A 20-year material]. / Fallots tetrade. Et 20 års materiale.

Surgical repair of tetralogy of Fallot may be a first stage palliation with secondary physiologic correction or repair as a primary procedure. The aim of palliation is to increase the pulmonary blood flow. Since 1981 we have used an interposition shunt between the subclavian and the pulmonary artery for this purpose. Repair comprises closure of the ventricular septal defect and relief of the pulmonary stenosis. A primary repair may be performed if the pulmonary arteries have reached a certain size. The size and function of the left ventricle must also be able to cope with the increased work load. During the last 20 years, 333 operative procedures have been performed in patients with tetralogy of Fallot. This material comprises 107 shunts and 226 repairs. The total mortality while in hospital was 6%. During the last period from 1990 until January 1993 the mortality in hospital was 3% after operative repair. There have been no mortality following palliative procedures during the same period.

Factors influencing survival in total anomalous pulmonary venous drainage.

Surgical repair of total anomalous pulmonary venous drainage was performed on 20 patients in 1977-1986. In univariate and multivariate and survival-curve analyses of clinical, anatomic and haemodynamic features, elevated diastolic pulmonary artery pressure was the only parameter prognostic of total mortality. The early mortality rate was 25% and the 5-year survival was 65 +/- 10.6%. Anastomotic stenosis occurred in four patients, three of whom underwent reoperation; one patient was twice operated on for such stenosis.

[Magnetic tomography in congenital heart defects]. / Magnettomografi ved medfødte hjertefeil.

Magnetic resonance imaging (MR) has been shown to be valuable in defining cardiac anatomy in a variety of cardiac abnormalities. The article describes the technique and results of MR in 32 children with congenital heart disease. MR clearly depicts the anatomy of the great vessels, and may be used for the evaluation of palliative systemic-pulmonary artery shunts. In postoperative controls, MR may replace or postpone angio-cardiography. MR is also a promising technique for the evaluation of myocardial and valvular function. Especially in small children, the non-invasive nature of MR is of great importance.

Balloon debanding of the pulmonary artery.

Clinical balloon debanding of the pulmonary artery is reported in two patients, 6 months and 4 years of age. The band was made of Dacron, and was closed with one single polypropylene suture. This suture was subsequently ruptured with a balloon inflated within the pulmonary artery at the site of the band. Balloon debanding relieved the gradient almost completely in the two patients. No problems occurred during the procedure. In the future this may prove to be an efficient and reliable way to remove the effect of a pulmonary artery banding.

Coarctation of the aorta, early and late results of various surgical techniques.

In the 10-year period 1973-1983, 158 patients aged one day to 16.4 years were operated upon for coarctation of the aorta; 25% of them were less than one month of age. The main surgical procedure was aortoplasty with a prosthetic patch (114 patients), and resection and end-to-end anastomosis (36 patients). Associated cardiovascular anomalies were found in 42%. There were 11 early and 6 late deaths and the majority of these were due to severe coexistent cardiac lesions. The frequency of moderate and severe recoarctation was much higher in patients operated on with resection and end-to-end anastomosis than in those with aortoplasty and prosthetic patch, 25% and 6.7%, respectively. In 18 patients, surgery for recoarctation was necessary using aortoplasty and a prosthetic patch technique. There were no postoperative complications or deaths in these patients. So far, in 2 cases with a prosthetic patch, aneurysmal dilatation of the aorta adjacent to the patch has developed.

[Aneurysm after patch graft aortoplasty in aortic coarctation]. / Aneurisme etter patchplastikk for coarctatio aortae.

In the period 1973-83, 114 patients with coarctation of the aorta were operated on with patch plasty. Early results were encouraging. Two of these patients had to be reoperated, however, because of aneurysmatic dilatation of the aorta adjacent to the prosthetic patch. In one case acute rupture of the aneurysm occurred eight years after the patch plasty, and surgery was performed under dramatic conditions as a life-saving procedure. In the other patient increasing dilatation of the distal part of the aortic arch was observed at chest X-ray 4-5 years after the operation. DSA revealed a large aneurysm proximal and distal to the site of coarctation, and he was operated with excision of the aneurysm and closure of the aorta with a patch of PTFE. Careful follow-up of patients operated for coarctation of the aorta is important. In addition to clinical investigation, patients with patch plasty must be referred to chest X-ray examination every 2nd to 3rd year for a relatively long time.

Senning operation for transposition of the great arteries in the first month of life.

Twelve patients with uncomplicated transposition of the great arteries were operated upon in the first month of life following an initial Rashkind procedure. They were all in a clinically unacceptable condition and were mostly acidotic or bad mixers without acidosis. Two patients died postoperatively from a cerebral haemorrhage not discovered prior to operation. One patient died 5 months postoperatively from bronchiolitis. At postoperative follow-up, all patients were asymptomatic. Cardiac catheterization showed that 1 patient had a significant upper caval vein stenosis, 2 patients had small atrial shunts, and 1 patient had an unimportant pulmonary stenosis. Innocent atrial rhythm disturbances were encountered in 1 case only, whereas 9 patients had normal sinus rhythm at the last examination. The Senning operation remains a good alternative for transposition repair in the neonate.

Altered natural killer cell activity in childhood acute non-lymphoid leukaemia. Augmented natural killer cell activity and cells expressing the Leu 7 and Leu 11b (CD 16) markers in the bone marrow of children in remission.

Peripheral blood and bone marrow mononuclear cells from 25 children with acute non-lymphoid leukaemia were analysed for natural killer cell activity and for cells with the Leu-7 and Leu-11b (CD 16) markers. Significantly reduced spontaneous cytotoxicity was detected in peripheral blood from children with untreated and active acute non-lymphoid leukaemia compared with that of the controls (P = 0.01 and P less than 0.05). Patients in remission, however, had normal natural cytotoxicity and normal numbers of Leu-7 and Leu-11b (CD 16)-positive cells. The natural killer cell activity in bone marrow from patients with untreated acute non-lymphoid leukaemia was also significantly reduced (P = 0.025). On the other hand, patients in remission had both an increased percentage of Leu-7 and Leu-11b (CD 16)-positive cells (P less than 0.05) and an increased natural killer cell activity (P less than 0.0005) in their bone marrow cells in comparison with the control group. This augmented natural killer cell activity is most probably a result of anti-leukaemic treatment. Stimulation with recombinant alpha interferon and recombinant interleukin 2 caused an increase in natural killer cell activity that was both significant and normal in both peripheral blood and bone marrow from children with acute non-lymphoid leukaemia.

In vitro balloon dilatation of the banded pulmonary artery.

The pulmonary artery of unfixated human heart-lung specimens was banded by placing a Dacron tape around the artery and securing the tape with a 5.0 Prolene suture at selected circumferences. The banding was successfully dilated with a balloon catheter in 24 instances. The mean pressure necessary to burst the suture securing the tape was 2.4 atmospheres.

Balloon dilatation of pulmonary artery banding in dogs: an experimental study.

The technique at our institution for banding of the pulmonary artery (PA) makes debanding by balloon dilatation theoretically possible. Previously we tested this hypothesis in an in vitro study (see previous article in this issue). This study describes balloon dilatation in dogs. Eight Labrador Retriever dogs had a PA band placed early in life, and when their body weight had doubled, they were restudied and debanded by balloon dilatation or surgical removal. One dog died of a virus infection before debanding and was excluded from the study. Five of the dogs (groups 1 and 2) underwent balloon dilatation with satisfactory relief of the gradient across the PA band. Two dogs (group 3) underwent surgical debanding without a plastic procedure on the PA, and this also produced satisfactory relief of the gradient. All dogs in group 2 and 1 dog in group 3 were studied 3 months later, and 1 dog in group 2 was also studied 6 months after the debanding procedure. The systolic pressure gradient fell from a mean of 54 to 18 mm Hg after the debanding procedure. There was no difference in the gradient after debanding in the balloon group compared to the surgical group.

Cerebral perfusion during major cardiac surgery in children.

Six children undergoing major cardiac surgery had extensive cerebral monitoring during cardiopulmonary bypass (CPB). The monitoring included continuous recording of arterial blood pressure (BP), central venous pressure (CVP), cerebral electrical activity by a cerebral function monitor (CFM), and middle cerebral artery (MCA) flow velocity by the transcranial pulsed Doppler (TCD) technique. Introduction of the precooled blood containing priming solution resulted in rapid fall in BP as well as MCA velocities in these children at the start of CPB. During steady-state CPB at 20 degrees C, MCA flow velocities were reduced in five of six children, range 45%-105% of pre-bypass value. These flow velocity values were recorded at cerebral perfusion pressures (CPP = BP - CVP) in the range of 14-26 mmHg. This reduced cerebral perfusion during steady-state CPB appears to be more than sufficient to meet the cerebral metabolic demands at the particular temperature. The reduced cerebral perfusion is in contrast to the enhanced perfusion found in adults during moderately hypothermic (28 degrees-30 degrees C) low-flow, low-pressure CPB previously reported. It was presumably due to the reduced temperature, reduced perfusion pressure, and less hemodilution. During periods of constant temperature, hematocrit, and partial pressure of carbon dioxide (PaCO2), MCA flow velocities varied passively with changes in CPP, demonstrating that cerebral autoregulation was not operative. Transcranial Doppler appears to be a suitable tool for investigating CPB techniques optimal with respect to cerebral circulation.

Echocardiographic evaluation of atrial function after Senning and Mustard correction for transposition of the great arteries.

Two groups of six children who had undergone either Senning or Mustard repair for uncomplicated transposition of the great arteries were studied with M mode echocardiography derived from a phased array sector scanner picture. The newly created atria were visualised from the subxiphoid region and the upper systemic venous inflow was selected for a simultaneous M mode registration with a subsequent wall motion analysis with a commercially available computer. In the Mustard group of patients the atrial walls seemed to move passively with the overall heart movements, while abrupt atrial wall excursions of both atria synchronous with heart action were noted in all patients after Senning repair. In this group also slow cyclic changes followed respiration. The atrial wall movements were significantly superior (p = 0.001) in the Senning group of patients. It is concluded that, in contrast to the Mustard method, the Senning operation seems to lead to a viable atrium with the capability of increasing and diminishing atrial diameter and with subsequent potential for growth.

Coarctation of the aorta in infancy.

In 57 infants with coarctation of the aorta severe congestive heart failure was the indication for surgical correction. More than half of them were less than 1 month of age. Associated cardiovascular anomalies were found in 48 patients. The surgical techniques utilized were resection and end-to-end anastomosis of the aorta and patch plasty using a Dacron patch or the left subclavian artery. The total mortality was 47%, and most of the deaths were due to severe associated cardiovascular anomalies. Of the 30 surviving patients 5 have been reoperated for coarctation 10 months to 8 years after the initial correction. However, recoarctation should be regarded not as an unsuccessful result but rather as a measure of the survival of these desperately ill infants.

Tricuspid atresia corrected with valved xenograft conduits.

In eight patients from 1976 until 1980, tricuspid atresia (TA) was corrected with valved xenograft conduits between either the right atrium and the main pulmonary artery or between the right atrium and the rudimentary right ventricle. All patients suffered from transient right-heart failure postoperatively and eventually developed normalized cardiac function throughout the first two months after operation. At recatheterization one year postoperatively, the right atrial pressure had generally only increased slightly, the pulmonary artery pressure was normal in all patients and only minor pressure differences were present across the valved conduits. X-ray examination showed normalization of the heart size in the majority of the patients, and in those with conduits between the right atrium and the right ventricle a considerable enlargement of the right ventricular chamber together with normalization of right ventricular contractility had developed. Arterial oxygen saturation, haemoglobin and haematocrit valves had normalized in all patients. One patient died postoperatively of intractable right ventricular failure, septicaemia and intravascular coagulation, and another was uneventfully re-operated on two years postoperatively because of conduit thrombosis. Clinical results were gratifying. Two patients with valved conduits between the right atrium and the right ventricle showed a normal unrestricted level of activity without medication, while patients with valved conduits between the right atrium and the main pulmonary artery were digitalized with an almost normal level of activity. Early repair with valved conduits of patients with TA is advocated.

"Balloon valvulotomy" of congenital pulmonary valve stenosis with tricuspid valve insufficiency.

The rare congenital anomaly of pulmonary valve stenosis and massive tricuspid valve insufficiency with intact ventricular septum is a lethal condition without reported survival after attempted treatment. In a neonate suffering from this syndrome, the pulmonary valve stenosis was relieved by rupturing the fused valve with a balloon catheter introduced transvenously. The desperate condition of the patient quickly improved after this procedure, with subsequent disappearance of the tricuspid valve incompetence. Balloon rupturing of fused valves at angiography may represent a therapeutic alternative in cases in which surgical valvulotomy is associated with a high mortality.

Correction of Fallot's tetralogy after palliative operations.

During the period 1960 to 1978, 98 patients underwent intracardiac repair of Fallot's tetralogy after palliative operations. Preoperative symptoms were cyanosis, dyspnea, increased fatigue with squatting and hypoxic spells. The hemoglobin concentration varied from 19 to 22 g/100 ml. At correction only 65 of 95 shunts were patent and needed surgical closure. Seventeen early deaths occurred (19%), the main causes being cardiac failure and arrhythmia. One patient died 3 years after correction from pneumonia. The subjective clinical result was excellent or good in all surviving patients. At repeat heart catheterization in 26 patients a high percentage of residual ventricular septal defects and pulmonary stenosis/insufficiency was found. However, the majority of defects were of minimal haemodynamic significance, and so far did not seem to do harm to the patients' subjective function.

Total anomalous pulmonary venous drainage.

Twelve patients with total anomalous pulmonary venous drainage (TAPVD) underwent complete surgical correction. Six were of the supracardiac type, 2 were cardiac and 4 of the infracardiac type. Pulmonary hypertension due to pulmonary vein obstruction was present in 6 patients. There were 6 early deaths, which occurred on the table or soon after surgery. One patient died 8 months after the operation because of a marked obstruction of the pulmonary venous inflow. Early diagnosis and operative correction in these severely ill patients should not be delayed. Postoperative intensive care and long-term follow-up are of the greatest importance.

The adhesiveness of blood platelets before, during and after cardiopulmonary bypass.

The influence of cardiopulmonary bypass on the adhesiveness of blood platelets, using both bubble (Bentley and Rygg-Kyvsgaard) and membrane (Landé-Edwards) oxygenators, was investigated. With both types of oxygenators, there was a considerable fall in platelet adhesiveness during cardiopulmonary bypass, particularly with the Rygg-Kyvsgaard apparatus. The adhesiveness increased 30 minutes after bypass, but it was still not restored to the initial value.

Transposition of great arteries. Early results of Mustard's operation in paediatric patients.

Between May 1969 and June 1975, 43 patients with d-transposition of the great arteries, ranging in age from 2 months to 13 years (mean 19 months), underwent surgical correction. In the first 3 patients Mustard's original method was followed. Later a modified procedure was performed using a Teflon patch. Forty-two of the 43 patients had previously had 50 various palliative procedures, of which 30 were balloon atrial septostomy only. Five patients died in hospital (up to 5 weeks after operation). Of the 32 patients with simple repair of transposition of the great arteries (including 3 with ligation of a persistent ductus arteriosus), 3 died. One patient died as a result of complete AV block, one as a result of renal damage associated with unrelieved coarctation of the aorta, and one of cerebral infarction and peritonitis which probably were initiated preoperatively. Six patients who had additional surgery for pulmonary stenosis survived, including 3 patients who had closure of ventricur septal defect, including 2 who had debanding of the pulmonary artery, 2 died in a low cardiac output state. One infant operated on for subpulmonary stenosis developed permanent complete AV block and was successfully treated with a pacemaker. All the patients with combined operations had some problems postoperatively. The survivors improved greatly, but 2 patients died suddenly one, and one and a half years after the operation respectively.