Active clinical trials for "Syncope"

In the present study the investigators evaluate the sensitivity and specificity of passive tilt test in athletes, as well as their haemodynamic responses and autonomic nervous system activity during head-up tilt. Moreover, the investigators try to apply a novel algorithm for the improvement of diagnostic yield of tilt test in athletes.

OBJECTIVES: To evaluate syncope recurrence at follow up in patients with a positive cardio inhibitory response to the head up tilt testing (HUT) evaluation. METHODS: 36 consecutive patients affected by cardio inhibitory syncope to HUT without asystolia (2A type) have been enrolled in this study. These patients have been studied by electrophysiological study (ES). After ES patients have been differently treated (interventional treatment group A, v/s drug therapy group), and followed up during 360 days, to evaluate syncope recurrences.

All patients consecutively referred with the first episode of transient and short-lasting loss of consciousness will have a diagnostic workup for the assessment of the most common causes of syncope, and will be evaluated for the presence of pulmonary embolism (PE) with the use of an internationally accepted algorithm including a pre-test clinical probability (PTP according to the method of Wells et al.) and a high-sensitivity quantitative D-dimer assay. If the PTP is low and D-dimer negative, PE will be excluded. All other patients will undergo confirmatory diagnostic tests (either computerized tomography or ventilation/perfusion lung scanning) in order to confirm or rule out the presence of PE.

The goal of this IDE clinical study is to evaluate the quality of the cardiac signal recordings obtained by the St. Jude Medical (SJM) Confirm Implantable Cardiac Monitor (device).

This is a prospective, controlled, opened randomized study to evaluate the cost benefit of a primary implantation of a loop recorder versus the conventional diagnostic cascade for syncope most likely due to cardiac arrhythmia.

Syncope is a common Emergency Department (ED) presentation but the underlying diagnosis is not apparent in 60% of patients after assessment and serious adverse event rate is 7% at one month with most having acute cardiovascular events, also more likely to be unexplained after ED assessment. Many cardiovascular events are due to arrhythmia, difficult for clinicians to diagnose, as examination and Electrocardiogram (ECG) findings may both be normal and symptoms have resolved by the time the patient gets to the ED. Currently establishing a cardiac arrhythmia as the cause of syncope rests on correlating the arrhythmia with symptoms using monitoring devices such as Holter but these all have significant drawbacks. The clinical challenge in the ED is therefore to identify the moderate and high-risk patients and refer them for further investigation and monitoring if appropriate. The logistics of arranging follow up within a timely period of the patient's ED visit is often problematic for a variety of reasons including availability of timely specialty outpatient appointments, a lack of consensus of the specialty to whom the syncope patient should be referred (cardiology, medicine, neurology, general practice) and availability of Holter and other monitoring devices. For this reason most high and medium risk patients are admitted to hospital. Previous syncope clinical decision rules have not been well adopted due to their lack of sensitivity and specificity probably due to the varied and heterogeneous nature of potentially serious causes. However, the majority of patients with syncope have no serious underlying pathology and do not require hospitalisation. Rather than continued attempts at risk stratification of outcome based on presentation, more research is required into how we can better improve diagnosis and therefore treatment in order to provide improved patient benefit. We believe that ambulatory patch monitoring will allow better and earlier arrhythmia detection and plan to assess the ability of a 14-day ambulatory patch to detect serious arrhythmic outcomes at 90 days.

This study uses an Alizarin Red powder mixture to characterize the sweat distributions in youth during tilt table testing. Patients with a known orthostatic sweat response from a prior clinical tilt table test in the investigators laboratory will be recruited. The Alizarin Red powder will be applied to exposed skin, and quantitative sweat will be measured at the thigh. During tilt testing, serial photos will be taken once the sweat response occurs. Sweat distributions will be compared during syncope (orthostatic sweat), during periods of anxiety (emotional sweat), and in patients with POTS (with and without syncope).

The purpose of this study is to explore changes in patients' hemodynamic parameters during the Head-Up Tilt Test ("HUTT") and their timing with respect to onset of the Closed Loop Stimulation (CLS) pacing. This study aims to add knowledge to better understand the mechanisms underlying recurrent syncopal events and optimal pacing programming.

To observe the safety and efficacy of ImageReady™ MR Conditional Pacing System in Chinese subjects

Suspension syndrome refers to a potentially life-threatening condition that can occur in unconscious persons after prolonged suspension in a harness. To date, our understanding of the pathophysiology and appropriate treatment is based primarily on case reports and expert opinion. The main pathophysiological hypothesis implicates blood pooling in the lower extremity and lack of return via muscle pumping. However, a recent French study could not support this hypothesis. Other mechanisms, such as a central vagal reflex may play a role in the pathophysiology of suspension syndrome. The aim of this study is to better understand the pathophysiological basis of suspension syndrome and to develop practical recommendations for prevention and treatment.