Cardioverter Discharges Following Sensing of Electrical Artifact Due to Fluid Penetration in the Connector Port

We report a unique case of fluid penetration, 3 months after implantation, in the connector port of an automatic implantable Cardioverter defibrillator (ICD) with transvenous subcutaneous lead system. The patient had coronary artery disease and recurrent episodes of ventricular fibrillation, the fluid caused electrical signals interpreted as ventricular fibrillation by the device, which triggered shock delivery .     

Induction of Life-threatening Ventricular Tachyarrhythmias by Serial Inappropriate AICD-pulsing in the Hyperthyroid State

A patient treated with the automatic implantable defibrillator exhibited serial inappropriate shacks during amiodarone-induced hyperthyroidism. This case illustrates the elective effectiveness of the AICD in the termination of ventricular tachyarrhythmias as well as its potency to induce them by serial erroneous interventions on supraventricular tachyarrhythmias so that external life-saving efforts are needed.     

Activity-Controlled Circadian Base Rate

The current pacing rates are clustered around a fixed base rate since pacemaker patients are usually sedentary, resting, or sleeping most of the time. This fixed base rate is either too low for daytime hemodynamic support or too high for nighttime rest and recovery. Multiple Holter studies involving normal individuals have suggested that the resting base rate fluctuates during the course of the day. The circadian base rate (CBR) algorithm was designed to provide patients with a circadian change in paced resting rate and a normal rate distribution. The CBR algorithm, using a sophisticated accelerometer sensor, was developed and tested using the downloaded activity data from patients implanted with Trilogy DR+ pacemakers. Twenty-five patients (19 men, 6 women, age 72 ± 9 years) were studied. Trilogy DR+ is able to record the detailed sensor and system behavior data for a week. During outpatient visits, the pacemaker was interrogated and the data accumulated in the pacemaker memory were downloaded. The CBR algorithm was applied to the activity variance histogram to calculate the base rate and to construct its histogram. The base rates in the CBR histogram are generally below 100 ppm with a distribution that mimics the natural sinus rate distribution of normal subjects. The CBR algorithm provides the highest daytime rates for hemodynamic support and the lowest nighttime rates for cardiac recovery, with a smoothly changing base rate modeling the normal circadian variation in heart rate.     

Long-term photochemotherapy: histopathological and immunofluorescence observations in 243 patients

Skin biopsies of 243 patients treated with photochemotherapy (PUVA) for 1--4 years were examined histologically. Two hundred and six patients were examined retrospectively after total cumulative UV-A doses of 579 . 6 +/- 598 . 0 J/cm2 (mean +/- s.d.). An eosinophilic homogenization and a reduction of elastic fibres at the dermo--epidermal junction, and an increase of dermal macrophages were found as possible abnormalities. However, except for the increase of melanophages there was no statistically significant correlation between the incidence of these changes, the total UV-A dose applied and the skin type of the patients. Neither were such correlations found in thirty-seven patients biopsies twice after 394 . 8 +/- 267 . 6 J/cm2 and 808 . 5 +/- 458 . 9 J/cm2 (mean +/- s.d.), respectively. Studies with direct immunofluorescence techniques revealed no immunoglobulin deposits in PUVA treated skin in fifty-six patients after 469 . 2 +/- 370 . 2 J/cm2; antinuclear antibodies were observed in 4 . 6% of 129 patients after 169 J/cm2 (mean); in 11% of fifty-three patients reexamined after 381 J/cm2 (mean) and in 13 . 6% of twenty-two patients reexamined a second time after 643 J/cm2 (mean). Thirteen out of a total of 572 patients developed a peculiar mottling of skin in areas previously overdosed by PUVA. Subepidermal homogenization and reduction of elastic fibres were found in 45% of the patients, indicating that these changes indeed are a consequence of PUVA. Nuclear and cellular irregularities were found in 45% of the biopsies and 63% showed a disturbed epidermal architecture, but no carcinomas were observed. PUVA-induced mottling was reversible in 31%, partially reversible in 15%, but continued to be present in 54%.