Syncope is when you lose consciousness temporarily, also known as fainting, passing out, or blacking out. It may last a few seconds or minutes. You should recover quickly and fully unless you injure yourself during your fainting episode.

You may require emergency care if you lose consciousness after a head injury, seizure, heart attack, or stroke. We do not consider this syncope.

Cardiac syncope vs vasovagal syncope

Cardiac syncope can be confused with vasovagal syncope, known as the common faint or neurocardiogenic syncope. Vasovagal syncope occurs as a response to a trigger that causes a sudden drop in blood pressure. These can include dehydration, seeing blood, having your blood taken, standing up too long or too fast, and experiencing a sudden and unexpected trauma. Some people with postural orthostatic tachycardia syndrome (POTS) experience this type of syncope.

Syncope can have many causes, but we’ll discuss those related to cardiac causes here. Cardiac syncope refers to syncope caused by a heart problem, such as a rhythm disturbance or a structural problem, that prevents the brain from receiving enough oxygen and nutrients.

Heart conditions that can cause syncope include: 

• An arrhythmia, such as ventricular tachycardia or a bradycardia
• Brugada syndrome, a genetic disorder that causes arrhythmias
• Aortic valve stenosis (narrowing of the aortic valve opening)
• Cardiovascular disease, such as heart disease
• QT interval disorders (Long or short QT)
• Aortic dissection (a tear in your aorta)

However, you can also faint due to dehydration, overheating, a sudden drop in blood sugar, exhaustion and stress. We recommend speaking to a doctor about your symptoms, including when you experience them. They may refer you to a cardiologist (heart specialist) if they suspect a heart condition is responsible for your fainting episodes. 

Once we have determined the cause, we will form a tailored treatment plan with you. You may require new medications or to change any you are taking, such as beta-blockers, calcium channel blockers, and other anti-arrhythmic agents.

If an arrhythmia causes syncope, we may recommend catheter ablation for a fast, irregular heartbeat or a pacemaker for a slow heartbeat. We may suggest an implantable cardioverter defibrillator (ICD) for people with ventricular tachycardia or heart failure. An ICD can also help prevent sudden cardiac death in those at risk.

A surgical procedure can treat a structural problem, such as an issue with your aortic valve or a narrowed or blocked artery. These procedures include aortic valve replacement or revascularisation techniques, such as angioplasty or coronary artery bypass graft (CABG).

Our specialist will discuss your treatment in depth so you understand its purpose and how it will work. We are happy to answer any questions to ensure you feel comfortable with our treatment plan.