[Magnetic resonance imaging in long-term assessment after surgery for aortic coarctation]. / Valoración a largo plazo con resonancia magnética en pacientes corregidos de coartación de aorta.

OBJECTIVES: Spin echo or gradient echo magnetic resonance imaging provides enough information to plan patient management and can be completed with the use of three-dimensional magnetic resonance angiography to evaluate the need for reintervention, assess follow-up, or discharge the patient. PATIENTS AND METHODS: From 1990-2003, we evaluated 101 patients after initial corrective surgery for aortic coarctation at the age of 3.1 +/- 3 years, with subsequent postoperative assessment at 1 year and again 12.4 +/- 4.2 years later. No mortality was registered during the follow-up. Corrective surgery was performed in 32 patients (31.6 %) before the first month of life. All the patients were evaluated with spin-echo and echo gradient and 34 were evaluated with magnetic resonance angiography. The patients were classified into two groups: group A consisted of 68 patients (11 < 1 month old) with no complications. End-to-end anastomosis was performed in 55, the Alvarez technique in five, the Waldhausen technique in six, and conduit in two. Group B consisted of 33 patients complicated with early aortic recoarctation (21 corrected before the age of 1 month). End-to-end anastomosis was performed in 29, the Alvarez technique in two, and grafting in two. During the follow-up, 43 reinterventions were performed. Isthmus diameter/descending aorta diameter at the diaphragmatic level and repaired site diameter/descending aorta diameter at the diaphragmatic level were measured. RESULTS: Group A: the isthmus diameter/descending aorta diameter at the diaphragmatic level index was 0.92 +/- 0.08 and the repaired site diameter/ descending aorta diameter at diaphragmatic level index was 0.90 +/- 0.05. Twenty-three patients were assessed by means of three-dimensional magnetic resonance angiography, which revealed two late stenosis (one in a 10-year-old patient with an end-to-end anastomosis performed previously, and another in an 18-year-old patient with a proximal and distal obstructed conduit). Group B: the isthmus diameter/descending aorta diameter index was 0.84 +/- 0.1 and the repaired site diameter/ descending aorta diameter index was 0.82 +/- 0.11. Eleven patients were assessed by means of three-dimensional magnetic resonance angiography, which revealed five stenosis indexes (0.53-0.73) surgically corrected before the age of 2 months, four with an initial technique based on end-to-end anastomosis and one with a graft. CONCLUSIONS: Our results support the influence of young age, the use of end-to-end anastomosis and grafts in recoarctation and their late influence on recurrent recoarctation. The patients in group A were discharged in childhood or adulthood after periodic follow-up every 5 years with magnetic resonance angiography for 18 years with results within the normal range, while patients in group B required longer follow-up.

Adrenal response to tolbutamide-induced hypoglycemia in high altitude dwellers.

Adrenal response to tolbutamide-induced hypoglycemia was studied in 23 normal men born and living at high altitude (Morococha, Perú, 4,540 m) and compared to 23 men born and living near sea level. Fasting blood sugar was significantly lower in the high altitude dwellers (HAD) and this difference persisted throughout the test period. The blood glucose decrement at 30 min was significantly less in the HAD. Plasma cortisol response was significantly higher at 30 and 60 min in the HAD. Peak cortisol level occurred earlier in the HAD than in men living at sea level. The absolute cortisol increment at 30 min was significantly greater in the HAD.

Luteinizing hormone and progesterone in women under postcoital contraception with D-norgestrel.

Luteinizing hormone (LH) and progesterone (Pg) levels in blood were measured simultaneously by radioimmunoassay during 53 menstrual cycles in order to investigate the effect of 400 mug of D-norgestrel, administered postcoitally, on pituitary and ovarian function. Of 31 control cycles, 2 appeared to be anovulatory, since the LH peak and subsequent Pg elevation were absent. Twenty-nine cycles showed typical LH surges in the middle of the cycle, followed by a manifold Pg increase. Twelve women received 5 to 13 tables of D-norgestrel. A total absence or at least marked suppression of LH and Pg elevations was observed. In a third group, D-norgestrel was administered on scheduled days. Each woman ingested one to four tablets between the 6th and 18th days of the cycle. Two or more tablets disturbed LH and Pg ovulatory patterns. Of four women who received a tablet on day 10, one failed to show characteristic ovulatory patterns and three exhibited a delay in the time of the LH and Pg increase. These results demonstrate that D-norgestrel in a postcoital regimen alters pituitary and ovarian function, strongly suggesting an antiovulatory effect.

Attaining United States and European guideline LDL-cholesterol levels with simvastatin in patients with coronary heart disease (the GOALLS study).

The effectiveness and safety of simvastatin in reducing low-density lipoprotein cholesterol (LDL-C) to target levels in patients with coronary heart disease (CHD) were evaluated in the GOALLS (Getting to Appropriate LDL-C Levels with Simvastatin) study. This multinational, multicentre, prospective, open-label, study consisted of a six-week diet washout period followed by a 14-week titrate-to-goal treatment period with simvastatin. One hundred and ninety-eight men and women with documented CHD and a fasting LDL-C level between 115 mg/dl (3.0 mmol/l) and 180 mg/dl (4.7 mmol/l) and triglycerides (TGs) < or = 400 mg/dl (4.5 mmol/l) were enrolled. The patients were started on 20 mg simvastatin with dose titration up to 80 mg if the LDL-C remained above 100 mg/dl at weeks 6 and 10. The key efficacy parameters were the percentage of patients achieving US and European LDL-C goals [< or = 100 mg/dl (2.6 mmol/l) and < or = 115 mg/dl (3.0 mmol/l), respectively]. Safety was evaluated by monitoring laboratory tests and recording adverse events. After 14 weeks of simvastatin (20-80 mg) treatment, approximately 90% of the patients achieved LDL-C goals according to US (87%) and European (94%) guidelines. Most patients (72-93%) achieved target LDL-C levels on 20 mg simvastatin. An estimated 14% of the patients required titration to the 80 mg dose. Treatment with simvastatin (20-80 mg) produced statistically significant improvements in all measured lipid variables by the end of the study. The mean reductions in total cholesterol and LDL-C, and the median reduction in TG, were 28%, 41% and 16%, respectively. The increase in high-density lipoprotein cholesterol and apolipoprotein A-1 were 5% and 4%, respectively. Simvastatin was well tolerated across the dosage range. In conclusion, simvastatin, 20-80 mg/day, was safe and highly effective at reducing LDL-C levels. The recommended US and European LDL-C treatment goals were achieved in approximately 90% of the patients. These goals were similarly achieved for a variety of high-risk sub-groups (hypertensives, diabetics and elderly patients).

Bouveret's syndrome: new cause of double-arch-shadow sign in cholecystosonography.

A case of Bouveret's syndrome which later presented as a jejunal obstruction is reported. Special reference is made to the echographic findings. Bouveret's syndrome has a double-arch-shadow image in the zone of the gallbladder bed on ultrasound examination. So far, this sign has been considered specific for gallstones inside the gallbladder.

Anaphylactic reactions to suxamethonium (succinylcholine).

We present the case of a woman who had two severe anaphylactic episodes with hypotension and bradycardia in relation to the administration of general anesthesia. In the allergy evaluation, IgE antibodies to suxamethonium, a muscle relaxant which was used in both procedures, were detected by skin prick tests. No cross-reaction was found to other muscle relaxants derived from quaternary ammonium. The patient was able to be operated on, and did not present any adverse reactions to the use of local anesthesia or to general anesthesia using pancuronium as a muscle relaxant.

[Hormonal variation during physical exertion at high altitude]. / Variaciones hormonales durante el esfuerzo físico en la altura.

The influence of the physical exercise at high altitude on the endocrine function was studied in 8 normal native men of sea level and in 8 natives men of high altitude. The sea level dwellers were studied both, at sea level, during an acute exposure to low barometric pressure and after 3 months of acclimatization to altitudes over 3,500 meters above the sea level. The experiments at high altitude were conducted at an altitude of 4,500 meters above the sea level. Two types of exercise were carried out, sub-maximal and maximal, at fasting state, between 8 and 10 a.m. During an acute exposure to altitude the physical exercise produced a marked rise of glucose, cortisol and growth hormone and a fall in the insulin content of plasma. In the sea level dwellers, acclimatized to altitude during 3 months, an elevation of growth hormone was observed only during maximal physical effort. Marked variation in glucose and cortisol were observed during both types of exercise. This shows that in these subjects some adaptative changes have ocurred but of lesser extent as those observed in altitude natives. In the high altitude native higher basal concentrations of growth hormone and glucagón as well as a lower glucose concentration in blood, were found. During exercise the high altitude dweller showed no significant changes in somatotropin, meanwhile an important elevation of cortisol occurred. These findings indicate that the high altitude native has metabolic and endocrine responses to exercise similar to those found in well fitted atletes of sea level. The exposure to altitude provoked a rise in glucagon concentration directly proportional to the time of exposition ot altitude. The physical exercise did not elucidate any change in the glucagon content of blood.

Subclavian artery to internal jugular vein fistula following percutaneous internal jugular vein catheterization.

The percutaneous internal jugular vein approach is now a commonly performed procedure for central venous catheterization. Iatrogenic arteriovenous fistulae are a very infrequent complication. We report an asymptomatic subclavian artery to internal jugular vein fistula following two percutaneous internal jugular vein catheterization attempts.

[Magnetic resonance of congenital cardiopathies]. / Resonancia magnética en las cardiopatías congénitas.

OBJECTIVE: The objective of this study was to determine the usefulness of magnetic resonance in the diagnosis and follow-up in congenital heart disease. PATIENTS AND METHODS: Between 1992 and 1994, we have evaluated 250 patients (between 1 day-22 years of age) with congenital heart disease. We used a Philips-Gyroscan 0.5 Tesla set-up and the studies were made with ECG-gated multislice sequences with the time of repetition adapted to the cardiac frequency. The slice thicknesses were 3-10 mm and the field of view was 100-400 mm. Three axes were used: axial, oblique coronal and 30-60 degrees oblique sagittal. Three groups were made: A) Patients in whom MR imaging was the elected technique for establishment of the diagnosis; B) Patients were MR imaging was an alternative technique; and C) Patients were MR imaging was complementary to other techniques. All patients underwent a Doppler echocardiographic study or an angiocardiogram. RESULTS: Group A) One hundred and fifty-one patients were included with the following conditions: Eighty-two with coarctation of the aorta or aortic arch interruption, 12 with vascular ring, 5 with truncus arteriosus in order to evaluate the pulmonary branches, 28 cases operated for Fallot or transposition of the great vessels for the evaluation of the pulmonary branches, 16 with single ventricle for the evaluation of the bulboventricular foramen, 5 with complex congenital heart disease and 3 with pericardial agenesia-herniation. Group B) Sixty-five patients were included in this group with the following diagnoses: Ten with aorto-pulmonary colateral arteries, 13 with anomalous pulmonary drainage of the systemic veins, 38 with tronco-conal anomalies and 4 with supravalvular aortic stenosis. Group C) Thirty-four patients with the following conditions were included in this group: Ten with common atrioventricular septal defects, 6 with tricuspid atresia, 6 with atrioventricular and ventriculoarterial discordance and 12 with other anomalies. CONCLUSIONS: MR imaging can replace other techniques in the diagnosis and follow-up of some congenital heart diseases and in a non-invasive way.