Percutaneous insertion of the Kimray-Greenfield filter: technical considerations and problems

Kimray-Greenfield filters were inserted percutaneously into the inferior vena cava (IVC) in 57 patients. Thirty-six were placed from the right femoral vein, 14 from the left femoral vein, and seven from the right internal jugular vein. There were no deaths or major complications and only six minor complications. Inferior vena cavography was done before filter insertion in all cases. Cavography is vital to determine feasibility of filter insertion, route of insertion, and filter location; pertinent findings include caval size, presence or absence of clot in the IVC or iliac veins, and position of the renal veins. The guide wire provided with the standard filter introduction set has a tendency to catch on the filter as the wire is withdrawn. A stiff wire with a straight, tapered, floppy tip was substituted. The femoral approach is preferred when it is feasible. Though there was only one known occurrence of femoral vein thrombosis at the filter insertion site, other cases may have occurred and may not have been detected. If the frequency of this complication proves to be significant, the preferred route for filter insertion may have to be reconsidered.     

PAROXYSMAL TACHYCARDIA IN INFANCY AND CHILDHOOD II. Paroxysmal Ventricular Tachycardia and Fibrillation

A retrospective 3–20-years follow-up study of 1 infant and 10 children with paroxysmal ventricular tachycardia (8 cases) or fibrillation (3 cases) is presented. Additional heart disease has been observed in 60% (myocarditis 3 cases, cardiomyopathy 3 cases, congenital heart disease 1 case). Symptoms of tachycardia were: palpitation, tiredness, weakness, dyspnoea, precordial and abdominal pain. Syncopes were observed in 3 cases; 1 child had no symptoms. Tachycardia of hours to days' duration have been noted in 8 patients, 7 had tachycardia of repetitive type with a-v dissociation, one continuous tachycardia without any intervening sinus beats after the onset of tachycardia and with retrograde atrial activation. The remaining 3 children had brief malignant tachycardia, i.e. stress-provoked bursts of ventricular activity occasionally converting to ventricular fibrillation causing syncope. The diagnosis of brief malignant tachycardia had to be based on exercise ECG (2 cases) or long-term ECG-monitoring by telemetry (one case). One child with cardiomyopathy had died at the time of follow-up and the 3 patients with brief malignant tachycardia had experienced repeated life-threatening attacks—one of which had to be stopped by emergency d.c. countershock. The period of attacks ceased in 5 cases within 2 years after onset, in 1 patient, 9 years elapsed between first and second attack. Preventive treatment with betablocking agents proved beneficial in the 3 children with brief malignant tachycardia.     

Early-life nutritional and environmental determinants of thymic size in infants born in rural Bangladesh

Aim:  The aim was to assess the impact of nutritional status and environmental exposures on infant thymic development in the rural Matlab region of Bangladesh.
Methods:  In a cohort of N_max 2094 infants born during a randomized study of combined interventions to improve maternal and infant health, thymic volume (thymic index, TI) was assessed by ultrasonography at birth and at 8, 24 and 52 weeks of age. Data on birth weight, infant anthropometry and feeding status were also collected.
Results:  At all ages, TI was positively associated with infant weight and strongly associated with the month of measurement. Longer duration of exclusive breastfeeding resulted in a larger TI at 52 weeks. TI at birth and at 8 weeks correlated positively with birth weight, but by 24 and 52 weeks and when adjusted for infant weight this effect was no longer present. Thymic size was not affected by pre-natal maternal supplementation or by socioeconomic status but was correlated to arsenic exposure during pregnancy.
Conclusion:  In this population of rural Bangladeshi infants, thymic development is influenced by both nutritional and environmental exposures early in life. The long-term functional implications of these findings warrant further investigation.     

Preimplantation diagnosis of non-deletion Duchenne muscular dystrophy (DMD) by linkage polymerase chain reaction analysis

The use of preimplantation diagnosis for sex determination and detection of exon deletion means that unaffected babies can be born to parents suffering from Duchenne muscular dystrophy (DMD). However, those who do not have exon deletion should also be considered for further investigation. A new method, known as linkage analysis, has been developed to diagnose the presence of non-deletion DMD in preimplantation embryos. Linkage analysis uses informative intragenic and flanking markers to track the chromosome bearing the mutated gene. The present study reports the analysis of two polymorphic sites, in blastomeres biopsied from embryos from a female carrier of DMD. A single male embryo was obtained who had inherited alternate maternal alleles to the woman's affected surviving son, and this embryo was transferred.