Diagnosis and management of neurocardiogenic syncope

Syncope in the Elderly

A rapid change in ageing demographic is taking place worldwide such that healthcare professionals are increasingly treating old and very old patients. Syncope in the elderly is a challenging presentation that is under-recognised, particularly in the acute care setting. The reason for this is that presentation in the older person may be atypical: patients are less likely to have a prodrome, may have amnesia for loss of consciousness and events are frequently unwitnessed. The older patient thus may present with a fall rather than transient loss of consciousness. There is an increased susceptibility to syncope with advancing age attributed to age-related physiological impairments in heart rate and blood pressure, and alterations in cerebral blood flow. Multi-morbidity and polypharmacy in these complex patients increases susceptibility to syncope. Cardiac causes and more than one possible cause are also common. Syncope is a major cause of morbidity and mortality and is associated with enormous personal and wider health economic costs. In view of this, prompt assessment and early targeted intervention are recommended. The purpose of this article is to update the reader regarding the presentation and management of syncope in this rapidly changing demographic.

Cardiovascular assessment of falls in older people

Falls in older people can be caused by underlying cardiovascular disorders, either because of balance instability in persons with background gait and balance disorders, or because of amnesia for loss of consciousness during unwitnessed syncope. Pertinent investigations include a detailed history, 12-lead electrocardiography, lying and standing blood pressure, carotid sinus massage (CSM), head-up tilt, cardiac electrophysiological tests, and ambulatory blood pressure and heart rate monitoring, which includes external and internal cardiac monitoring. The presence of structural heart disease predicts an underlying cardiac cause. Conversely, the absence of either indicates that neurally mediated etiology is likely. CSM and tilt-table testing should be considered in patients with unexplained and recurrent falls. Holter monitoring over 24 hours has a low diagnostic yield. Early use of an implantable loop recorder may be more cost-effective. A dedicated investigation unit increases the likelihood of achieving positive diagnoses and significantly reduces hospital stay and health expenditure.

Preliminary Observations on the Effect of Amitriptyline Treatment in Preventing Syncope Recurrence in Patients with Vasovagel Syncope

PURPOSE

Vasovagal syncope is a common and challenging problem that may result in injury and causes substantial anxiety among patients and their relatives. However, treatment of vasovagal syncope with standard pharmacologic approaches is not satisfactory. The aim of this study is to investigate the effect of amitriptyline, a tricyclic antidepressant drug, by using its anticholinergic effects in preventing syncopal episodes in patients with vasovagal syncope.

METHODS

In this study, 74 patients (mean age 24 +/- 1.9 years, 26 male) with a history of recurrent syncope and baseline positive head-up tilt table test (syncope or presyncope) were included. Oral amitriptyline treatment was given to all patients, with a starting dose of 10 mg once a day. Head-up tilt table test was performed in all patients 4 weeks after the treatment started. Patients were followed up clinically for 6 months.

RESULTS

After 4 weeks, during head-up tilt table test in 69 patients (93%), syncope or presyncope was not seen and test was assumed as negative. At the end of the 6th month, 67 patients (91%) were free of symptoms. Only two patients (0.3%) did not tolerate amitriptyline due to side effects.

CONCLUSIONS

Oral amitriptyline can be used in the prevention of recurrent episodes of vasovagal syncope safely. However, randomized controlled studies are essential to assess the real effectiveness of this therapy.

Assessment of autonomic activity during daily life of patients with head-up tilt-induced prolonged asystole

Autonomic activity is important in the pathophysiology of neurally mediated syncope (NMS) patients diagnosed by the head-up tilt (HUT) test, and prolonged systole induced by HUT is associated with a malignant vasovagal syndrome. This study investigated whether or not daily autonomic activity evaluated by heart rate variability (HRV) assessed through 24-hour ambulatory ECG monitoring was augumented in HUT-induced asystole (AS; > 30 s) and whether or not HRV differed between NMS patients with and without AS. Ambulatory ECG monitoring was performed in 176 patients with suspected NMS and in 62 age-matched healthy control subjects (C group, age: 36 +/- 13 yr), with HRV time and frequency domain indices measured within 48 hours of HUT. Six patients displayed prolonged AS (PAS group, age: 33 +/- 12 yr), and 109 patients had positive HUT (P group, age: 29 +/- 17 yr), while 61 patients had negative HUT (N group, age: 40 +/- 18 yr). Several HRV indices in the P group were higher than those in the N and C groups. However, HRV indices did not differ between the P group and the PAS group. It is concluded that impairment of autonomic activity specifically related to orthostatic stress could be important in the pathophysiology of HUT-induced prolonged asystole, while impairment of autonomic activity in daily life is not as important in NMS patients with HUT-induced prolonged asystole.

Diagnosis and Management of Vasovagal Syncope and Dysautonomia

Vasovagal syncope is a condition better known as neurocardiogenic or neurally mediated syncope. Dysautonomic syncope is the irregular neuroautonomic response during the body's attempt to maintain homeostasis. Both types of syncope are associated with orthostatic hypotension and are nonlethal. The underlying pathophysiology manifests the vast symptoms suffered by the individual. Research continues to develop new markers to improve diagnostic testing and therapies for treatment. Advanced practice nurses now have a new tool with Head-Up Tilt Training Programs to offer the patients who suffer from frequent and refractory neurocardiogenic and dysautonomic syncope.