Implantation of a Dual Chamber Pacing and Sensing Single Pass Defibrillation Lead

GRADAUS, R., et al. : Implantation of a Dual Chamber Pacing and Sensing Single Pass Defibrillation Lead. Dual-chamber ICDs are increasingly used to avoid inappropriate shocks due to supraventricular tachycardias. Additionally, many ICD patients will probably benefit from dual chamber pacing. The purpose of this pilot study was to evaluate the intraoperative performance and short-term follow-up of an innovative single pass right ventricular defibrillation lead capable of bipolar sensing and pacing in the right atrium and ventricle. Implantation of this single pass right ventricular defibrillation lead was successful in all 13 patients (  age 63 ± 8 years  ; LVEF  0.44 ± 0.16  ; New York Heart Association [NYHA]  2.4 ± 0.4  , previous open heart surgery in all patients). The operation time was  79 ± 29  minutes, the fluoroscopy time  4.7 ± 3.1  minutes. No perioperative complications occurred. The intraoperative atrial sensing was  1.7 ± 0.5 mV  , the atrial pacing threshold product was  0.20 ± 0.14 V/ms  (  range 0.03–0.50 V/ms  ). The defibrillation threshold was  8.8 ± 2.7 J  . At prehospital discharge and at 1-month and 3-month follow-up, atrial sensing was  1.9 ± 0.9, 2.1 ± 0.5, and 2.7 ± 0.6 mV  , respectively, (  P = NS, P < 0.05, P < 0.05  to implant, respectively), the mean atrial threshold product  0.79, 1.65, and 1.29 V/ms  , respectively. In two patients, an intermittent exit block occurred in different body postures. All spontaneous and induced ventricular arrhythmias were detected and terminated appropriately. Thus, in a highly selected patient group, atrial and ventricular sensing and pacing with a single lead is possible under consideration of an atrial pacing dysfunction in 17% of patients.     

IMMUNOLOGICAL AND GENETIC MARKERS IN A FAMILY WITH HASHIMOTO'S DISEASE

A family with Hashimoto's disease in three generations is described. Seven persons (all female) had Hashimoto's disease and four of them were initially hypothyroid. Hashimoto's disease was the only thyroid disorder occurring in this family; no other autoimmune disease was observed. Circulating thyroid antibodies were detected in all seven subjects with overt thyroiditis in this family. Thyroid antibodies were also detected in low titres in about half of the healthy relatives. Evidence of thyroid antigen-directed cell-mediated immunity was demonstrated using the leucocyte migration inhibition test in four out of seven subjects with thyroiditis and also in about half of the relatives without clinical thyroid disease. The relative number of thyroglobulin-binding circulating lymphocytes was elevated in six subjects with Hashimoto's disease. Again, the percentage of such cells was also increased in about half of the‘healthy’relatives. Thyroid-stimulating immunoglobulins were detected by the radio receptor assay in three of the seven subjects with Hashimoto's disease and in four out of thirteen relatives without overt signs of thyroiditis. In conclusion, all subjects with Hashimoto's disease carried immunological markers of autoimmune thyroid disease in the circulation. In addition, most of the‘healthy’relatives were also positive for some or all of the markers sought in this study. The expression of these markers thus seems to be variable. No clear-cut conclusion could be drawn regarding the inheritance of these markers. H LA genotypes were assayed for thirty-five specificities of A, B and C loci and five of the D loci. There was no correlation between any individual antigen or HLA haplotype and overt Hashimoto's disease in this family.