Long-term results of endocardial pacing with Autocapture™ threshold tracking pacemakers in children

PubMedID: 16216759Aim: We aimed to evaluate the long-term results of endocardial pacing with Autocapture™ threshold tracking pacemakers in children. Methods and results: Implantation and follow-up data of 20 children with these pacemakers were retrospectively evaluated. The pacemakers were implanted subpectorally in five and subcutaneously in 15 patients. The indication for pacing was high-grade atrioventricular block in 18 cases. The mean age at implantation was 7 ± 4.8 years. Four patients were pacemaker dependant (heart rate < 30 bpm). At implantation, the mean pacing threshold was 0.5 V at 0.5 ms. The mean evoked response (ER) signal was 8.5 ± 3.6 mV, and the polarisation signal (PS) was <1 mV in 15 patients and 1-2 mV in five patients. During the mean follow-up period of 60 months, mean ER signal decreased significantly to 7.7 ± 6.3 mV at 24 months and 6.5 ± 2.5 mV at 60 months (P < 0.05). In four of 15 patients (26.6%), with a predischarge PS value of <1 mV, it increased between 1 and 2 mV over time. During follow-up, autocapture function was deactivated in six (30%) patients; due to inappropriate ER/PS values in four and due to severe muscle twitching in two with subpectoral implants. These problems occurred during a median period of 21 months after implantation. Generators were replaced in three patients with Microny pacemakers because of battery depletion at 54, 66 and 78 months. In two of them autocapture function had been working since implantation. In seven of 10 patients, who completed ?60 months of follow-up, battery impedances were still at the predischarge level. Conclusions: Autocapture function works well in most children at implantation. Mean ER signal significantly decreases over time despite stable pacing parameters. Autocapture function may become nonoperational due to decreased ER signal in some patients. Muscle twitching may be an important problem that may result in discontinuation of autocapture function in children with subpectoral implants. © 2005 The European Society of Cardiology. Published by Elsevier Ltd. All rights reserved

Migraine Patients with or without Vertigo: Comparison of Clinical and Electronystagmographic Findings

Objective: To find the differences between patients with migraine with and without vertigo. Study Deslgn: A prospective study. Setting: Ambulatory dizziness centre of a tertiary referral hospital. Methods: Eighty-four patients with migraine (31 with headache, 53 with headache and vertigo) according to the diagnostic criteria of migraine published by the International Headache Society in 1988 were included in the study. Patient history, vestibular tests, electronystagmography (ENG), and imaging studies were performed for differential diagnosis. Main Outcome Measures: Clinical findings and ENG parameters. Results: Fifty-three of 84 patients (63%) had episodic vertigo attacks. Vertigo was independent from headache in 24 patients (45%). Vertigo symptoms always appeared later in the history of migraine headache. Headache started at age 27 ± 8.3 years and vertigo symptoms began 7.7 ± 8. 7 years later. The beginning age of the migraine and female-to-male ratio were significantly greater in the vertigo group. Fifty-eight of the 84 patients had ENG testing. Fifty-eight percent of the patients with migraine and 55% of the patients with migraine + vertigo had abnormal ENG findings. None of the tests except the Dix-Hallpike manoeuvre had a statistically significant difference between the two groups. Conclusion: The presence of the same ENG abnormalities in patients with pure headache shows that the vestibular pathways are also affected in these patients, even when there are no vestibular symptoms