From the Guidelines
Cardiac syncope can be effectively managed with treatments tailored to the underlying cause, including pacemaker implantation, catheter ablation, antiarrhythmic drug therapy, and implantable cardioverter-defibrillator (ICD) placement, as recommended by the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1. The potential solutions for cardiac syncope include:
- Pacemaker implantation for patients with sinus node disease, second-degree Mobitz II, advanced or complete AV block, or bundle branch block with positive electrophysiological study (EPS) results, as suggested by the 2009 guidelines for the diagnosis and management of syncope 1
- Catheter ablation for patients with symptom-arrhythmia ECG correlation in supraventricular tachycardia (SVT) or ventricular tachycardia (VT) without structural heart disease, as recommended by the 2009 guidelines 1
- Antiarrhythmic drug therapy, including rate control drugs, for patients with syncope due to onset of rapid atrial fibrillation, as suggested by the 2009 guidelines 1
- Implantable cardioverter-defibrillator (ICD) placement for patients with documented VT and structural heart disease, or for patients with inherited cardiomyopathies or channelopathies, as recommended by the 2009 guidelines 1
- Hospital evaluation and treatment for patients presenting with syncope who have a serious medical condition potentially relevant to the cause of syncope, as recommended by the 2017 ACC/AHA/HRS guideline 1 The choice of treatment depends on the underlying cause of the syncope, and a thorough evaluation, including EPS and imaging studies, may be necessary to determine the best course of treatment. Some key points to consider when managing cardiac syncope include:
- Identifying the underlying cause of the syncope, such as cardiac arrhythmias, structural heart disease, or other conditions
- Selecting the most appropriate treatment based on the underlying cause, such as pacemaker implantation, catheter ablation, or antiarrhythmic drug therapy
- Monitoring treatment effectiveness and adjusting therapy as needed to prevent recurrent syncope and improve quality of life, as recommended by the 2017 ACC/AHA/HRS guideline 1.
From the Research
Potential Solutions for Cardiac Syncope
The potential solutions for cardiac syncope can be identified through a careful evaluation of the patient and assignment of the identified mechanism of syncope to either a hypotensive or bradycardic phenotype.
- Mechanism-specific treatment strategies include:
- Evaluation of the patient with syncope is mandatory, and if the underlying cause of syncope can be diagnosed during initial evaluation, the patient should be treated accordingly 3
- If the cause of syncope remains unclear, the patient has to be stratified with respect to the risk of a cardiovascular event and sudden cardiac death, and further evaluation initiated 3
- Prolonged electrocardiographic monitoring, stress testing, and echocardiography may be beneficial in patients at higher risk of adverse outcomes from cardiac syncope 4
- A 12-lead electrocardiogram (ECG) is the only instrumental test recommended for the initial evaluation of patients with suspected syncope, and may disclose an arrhythmia associated with a high likelihood of syncope 5
Diagnosis and Risk Stratification
- A careful, well-conducted medical history focused on the suspected syncopal event is crucial for the diagnosis 5
- The ECG is a mandatory diagnostic tool which, although normal in the majority of patients with syncope, has the potential to identify patients with high likelihood of cardiac syncope due to arrhythmic or cardiopulmonary disorder 5
- Risk stratification tools, such as the Canadian Syncope Risk Score, may be beneficial in informing decisions regarding hospital admission 4
- The prognosis of patients with cardiac syncope is more likely to be associated with adverse outcomes, whereas patients with reflex and orthostatic syncope have a good prognosis 4