New ESC syncope guidelines stratify patients who may be discharged from the ED safely
An algorithm to help stratify patients with syncope requiring hospitalization vs those that can be discharged from the emergency department (ED) safely forms part of the new European Society Cardiology (ESC) syncope guidelines launched at the EHRA 2018 meeting.
Syncope is defined in the guidelines as a transient loss of consciousness (TLOC) due to cerebral hypoperfusion, characterized by a rapid onset, short duration, and spontaneous complete recovery. For TLOC to be established, there should be a loss of awareness or amnesia, loss of motor control as in falling, and loss of responsiveness that is of short duration.
When is hospital admission not an option
The new guidelines recommend that patients with predominantly low-risk features, such as those with reflex, situational, or orthostatic syncope, be discharged directly from the ED with adequate patient education. If syncope episodes are recurrent, patients can be managed at syncope outpatient clinics. This was following an initial syncope examination that includes a physical exam, medical history and blood pressure taking, and electrocardiography at the ED. [EHRA 2018, presentations 75-79; Eur Heart J 2018;doi.org/10.1093/eurheartj/ehy037]
Patients with high-risk features (likely those with cardiac syncope), on the other hand, should receive an urgent and timely investigation at the ED and may require hospital admission, said guidelines task force member Dr Matthew J Reed, an emergency medicine consultant at Edinburgh University, Edinburgh, UK. Those falling between low-and high-risk should be observed in the ED, syncope observational unit, or syncope outpatient clinic, if available, instead of being hospitalized.
“The guidelines aim to reduce admission in syncope patients using novel strategies such as syncope units and emergency observation units where patients can be rapidly assessed, observed for 6-24 hours, and managed by syncope experts, then safely discharged without having to be admitted to the hospital,” Reed said.
“Hospitalization is not the most appropriate thing for the majority of syncope patients. However, 75 percent of the cost of syncope is hospitalization; so, if we can cut hospitalization, we cut 75 percent of the cost,” said task force chair Dr Michele Brignole from Ospedali Del Tigullio in Lavagna, Italy,
Reed added that there are many syncope risk-stratification scores available but these perform no better than clinical judgment at predicting short-term outcomes. “Hence, we don’t recommend routine use of these scores.”
Video recording a new feature in the guidelines
A new recommendation that was not in the 2009 syncope guidelines is the adoption of video recording to tilt-table testing (a tool to distinguish reflex syncope, particularly of hypotensive tendency) during syncopal episodes or falls to aid clinical assessment.
“Patients and their relatives should be urged to record attacks, if possible, in cases of diagnostic uncertainty,” said task force co-chair Dr Angel Moya from the Hospital Universitario Vall d'Hebron in Barcelona, Spain. “This gives us information to be able to make a differential diagnosis between syncope and epilepsy.”
The guidelines also recommend that clinicians consider basic cardiovascular autonomic function tests such as the Valsalva manoeuvre, deep-breathing test, or ambulatory and home blood pressure monitoring, in patients suspected of having neurogenic orthostatic hypotension. ECG monitoring is indicated only when there is a high pre-test probability of identifying an arrhythmia associated with syncope.
Finally, the guidelines recommend extending the use of implantable loop recorders (ILRs) to aid diagnosis in patients with unexplained falls, suspected epilepsy, or recurrent episodes of unexplained syncope with a low risk for sudden cardiac death as an alternative to implantable cardioverter defibrillator (ICD).
Other indications for ILRs are in patients with recurrent syncope of uncertain origin, no high-risk criteria, and a high likelihood of recurrence; those with high-risk criteria in whom a comprehensive evaluation failed to identify the cause of syncope or lead to a specific treatment; and those who have no primary prevention indications for ICD or pacemaker.
How to treat syncope
Treatment of syncope is based on risk stratification and identification of specific mechanisms rather than the aetiology, according to Moya. Cardiac pacing is recommended as the most powerful therapy for bradycardia, a common mechanism of syncope, but its efficacy is reduced in the presence of hypotension.
For recurrent and unpredictable reflex syncope, treatment is mainly non-pharmacological, including education, lifestyle modification, and patient reassurance regarding the benign course of syncope, with age as the most important discriminant for the choice of therapy. For cardiac syncope (arrhythmia or structural cardiac disease), therapy should be targeted towards the underlying disease. For those with unexplained syncope at high-risk of sudden cardiac death (SCD), physicians may consider ICD therapy.
“We need to explain the diagnosis, reassure, explain the risk of recurrence, and give advice on how to avoid triggers and situations in patients with reflex syncope and orthostatic hypotension,” said Moya.
In those with unexplained syncope at high-risk of SCD, for example, those with Brugada syndrome, hypertrophic cardiomyopathy, or reduced left ventricular ejection fraction, “the risk of SCD increases by two to fourfold, hence we should be attentive to these type of patients,” added Dr Vincent Probst, cardiologist at CHU de Nantes, Hôpital Nord, France. “If the aetiology of syncope remains unidentifiable despite conventional workups, patients can be managed with ICD, or implantable loop recorder, to ensure that the syncope is not in relation to arrhythmia.”
He said physicians are encouraged to take the ESC guidelines into account when exercising clinical judgment and implementing preventive, diagnostic, or therapeutic interventions for patients with syncope.