In the last decades we are observing a continuous increase in the number of patients wearing cardiac implantable electronic devices (CIEDs). At the same time, we face daily with a domestic and public ...environment featured more and more by the presence and the utilization of new emitters and finally, more medical procedures are based on electromagnetic fields as well. Therefore, the topic of the interaction of devices with electromagnetic interference (EMI) is increasingly a real and actual problem.In the medical environment most attention is paid to magnetic resonance, nevertheless the risk of interaction is present also with ionizing radiation, electrical nerve stimulation and electrosurgery. In the non-medical environment, most studies reported in the literature focused on mobile phones, metal detectors, as well as on headphones or digital players as potential EMI sources, but many other instruments and tools may be intentional or non-intentional sources of electromagnetic fields.CIED manufacturers are more and more focusing on new technological features in order to make implantable devices less susceptible to EMI. However, patients and emitter manufacturers should be aware that limitations exist and that there is not complete immunity to EMI.
This document has been developed by the Lazio regional chapters of two scientific associations, the Italian National Association of Hospital Cardiologists (ANMCO) and the Italian Society of Emergency ...Medicine (SIMEU), whose members are actively involved in the everyday management of Acute Coronary Syndromes (ACS). The document is aimed at providing a specific, practical, evidence-based guideline for the effective management of antithrombotic treatment (antiplatelet and anticoagulant) in the complex and ever changing scenario of ACS. The document employs a synthetic approach which considers two main issues: the actual operative context of treatment delivery and the general management strategy.
Background: Head-up tilt testing is widely used in the clinical assessment of patients with unexplained syncope. However, the lack of a standard methodology and the conflicting results concerning ...sensitivity and specificity of the procedure have prompted further studies to define a more cost-effective approach for tilt testing.
Objectives: Our clinical investigation was undertaken to assess the diagnostic value in unexplained syncope of a simple and time-saving protocol for head-up tilt testing, including low-dose sublingual isosorbide dinitrate administration.
Patients and Methods: A group of 73 consecutive patients (43 women and 30 men, mean age 39.6 ± 21.8 years) with unexplained syncope despite conventional clinical cardiovascular and neurologic assessment and 10 asymptomatic control subjects underwent head-up tilt testing with isosorbide dinitrate challenge. Participants were tilted at 60 degrees for 30 minutes without medication; if no symptoms occurred, 1.25 mg of isosorbide dinitrate was administered sublingually and tilting was continued for an additional 15 minutes.
Results: During the drug-free phase of the test 14 (19.2%) patients had syncope. After isosorbide dinitrate administration syncope occurred in another 28 patients (38.3%); minor symptoms in association with hypotension developed in 10 (13.7%) patients. The test result was negative in all control subjects. The positive rate and specificity of head-up tilt testing with isosorbide dinitrate provocation were 57.5% and 100%, respectively.
Conclusions: This new practical diagnostic procedure was found to be fairly sensitive and clearly specific in inducing a vasovagal reflex in patients with syncope of uncertain origin. Consequently, such approach could give a significant contribution in the diagnostic workup of these patients. (Am Heart J 1998;135:671-6.)
We sought to determine whether the introduction of EEG monitoring during head-up tilt testing could significantly improve the understanding of the cerebral events occurring during tilt-induced ...vasovagal syncope and the potential danger to the patient of this diagnostic procedure.
EEG monitoring was performed during head-up tilt testing in a group of 63 consecutive patients (27 males and 36 females; mean age, 41.5 years) with a history of recurrent syncope of unknown origin despite extensive clinical and laboratory assessment.
Syncope occurred in 27 of 63 patients (42.8%) during head-up tilt testing and was found to be cardioinhibitory in 11 of 27 (40.7%) and vasodepressor in 16 of 27 (59.3%). All patients with a negative response to head-up tilt testing showed no significant EEG modifications. In patients with vasodepressor syncope, a generalized high-amplitude, 4- to 5-Hz (theta range) slowing of EEG activity appeared at the onset of syncope, followed by an increase of brain-wave amplitude with the reduction of frequency at 1.5 to 3 Hz (delta range). The return to the supine position was associated with brain-wave amplitude reduction and frequency increase to 4 to 5 Hz, followed by restoration of a normal EEG pattern and arousal (mean total duration of syncope, 23.2 seconds.). In patients with cardioinhibitory syncope, a generalized high-amplitude EEG slowing in the theta range was noted at the onset of syncope, followed by a brain-wave amplitude increase and slowing in the delta range. A sudden reduction of brain-wave amplitude then ensued, leading to the disappearance of electrocerebral activity ("flat" EEG). The return to the supine position did not allow either the immediate resolution of EEG abnormalities or consciousness recovery, both of which occurred after a further time interval (mean total duration of syncope, 41.4 seconds.).
EEG monitoring during head-up tilt testing allowed recording and systematic description of electrocerebral abnormalities developing in the course of tilt-induced vasovagal syncope.
Responsabilidad Las Guías de Práctica Clínica recogen la opinión de la ESC y se han elaborado tras una consideración minuciosa de las evidencias disponibles en el momento en que fueron escritas. Se ...anima a los profesionales de la sanidad a que las tengan en plena consideración cuando ejerzan su juicio clínico. No obstante, las Guías de Práctica Clínica no deben invalidar la responsabilidad individual de los profesionales de la salud a la hora de tomar decisiones adecuadas a las circunstancias individuales de cada paciente, consultando con el propio paciente y, cuando sea necesario y pertinente, con su tutor o representante legal. También es responsabilidad del profesional de la salud verificar las normas y los reglamentos que se aplican a los fármacos o dispositivos en el momento de la prescripción.
Background: The effectiveness of cardiac pacing in preventing vasovagal syncope remains controversial. However, DDI pacing with rate hysteresis has been reported to prevent the recurrence of ...Cardioinhibitory vasovagal syncope in up to 35% of affected subjects and to reduce the overall incidence of syncopal episodes in the others. Recently, DDD pacing with a new promising rate drop response function (Medtronic Thera‐I model 7960) has become available in clinical practice. Aim of the study: The aim of the present open trial was to test the effectiveness of this new pacing modality in patients with Cardioinhibitory vasovagal syncope. Study population and methods: The study population included 20 patients (12 males and 8 females; mean age 61.1 ± 14 yrs) with recurrent syncope (mean number of prior episode = 6.8, range 5–11) and Cardioinhibitory responses during two head‐up tilt tests: the first diagnostic and the second during drug therapy with either β‐blockade or etilephrine. The study patients were randomized to receive either DDI pacing with rate hysteresis (8 patients) or DDD pacing with rate drop response function (11 patients). The head‐up tilt test performed 1 month after pacemaker implantation was positive in 3 of 12 patients (25%) with DDD pacing with rate drop response function and in 5 of 8 patients (62.5%) with DDI pacing with rate hysteresis. The mean duration of follow‐up was 17.7 ± 7.4 months. During follow‐up no patients with a DDD pacemaker with rate drop response function had syncope, while 3 of 8 patients with a DDI pacemaker with rate hysteresis had recurrence of syncope (P < 0.05). Conclusions: These data suggest that DDD pacing with rate drop response function is effective in Cardioinhibitory vasovagal syncope and may be preferable to DDI pacing with rate hysteresis.
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