A novel approach to eliminate intraventricular lead placement in patients with congenital heart disease

Purpose

We describe two patients with congenital heart disease who were referred for implantable cardioverter-defibrillator (ICD) placement. Both patients possessed factors causing the conventional transvenous approach to be undesirable. We therefore devised a technique which circumvented both intravascular ICD lead placement, as well as placement of leads across the tricuspid valve.

Methods

For both patients, a bipolar pace?Csense lead was successfully placed in a branch of the coronary sinus. A shocking coil was then tunneled from the posterolateral margin of the device pocket, being positioned posterior and inferior to the cardiac silhouette. Defibrillation testing was carried out with goal of a 10-J safety margin.

Results

We were able to successfully achieve ICD implantation in both patients with complex congenital heart disease without requirement for surgical thoracotomy or a lead across the AV valve. R waves in excess of 5?mV were obtained and acceptable defibrillation characteristics were achieved. Both patients are doing well after mid-term follow-up.

Conclusion

A new implant approach is presented, which involves minimal intravascular hardware and eliminates passage across the atrioventricular valve for patients with congenital heart disease in whom conventional ICD implant techniques may be undesirable or not possible. This procedure is technically straightforward with proper technique and knowledge of the patient specific anatomy.     

Vitamin D receptor gene polymorphisms and bone mass indices in post-menarchal Indian adolescent girls

To study the association between vitamin D receptor (VDR) gene polymorphisms and bone mass indices in adolescent girls, a cross-sectional study was conducted in 120 post-menarchal girls aged 15–18 years in Pune city, India. Serum levels of ionised calcium, inorganic phosphorous, parathyroid hormone and 25-hydroxy vitamin-D were measured. Bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) were measured at total body (TB), lumbar spine (LS) and left femoral neck (FN) using dual energy X-ray absorptiometry. Polymorphisms of the VDR gene at the Fok1 and Bsm1 loci were detected using SYBR Green quantitative polymerase chain reaction. The overall distribution of genotypes at the Bsm1 locus in this study was 33.3 % Bb, 29.2 % bb and 37.5 % BB while that for the Fok1 locus was 44.2 % Ff, 7.5 % ff and 48.3 % FF. There were no significant differences in the blood parameters when classified according to Bsm1 or Fok1 genotypes. Subjects with BB genotype have significantly higher mean TBBMC, TBBA, TBBMD and LSBMD than Bb and bb (p < 0.05) and showed a tendency for association with LSBMC and LSBA (p < 0.1). Subjects with Ff genotype showed a tendency for association with left FNBMC and FNBA (p < 0.1). Bsm1 genotype did not show an association with FN bone indices whereas Fok1 genotype did not show association with TB or LS bone indices. In conclusion, the present study demonstrates VDR gene polymorphism, defined by Bsm1 genotype, has an influence on total body and lumbar spine bone mass indices in post-menarchal Indian girls.