What is cannon a waves?

Cannon A waves are a type of abnormal waveform that can occur on an electrocardiogram (ECG) or an invasive intracardiac electrophysiological study. These waves are typically seen in patients with certain types of heart conditions, such as atrioventricular block or ventricular tachycardia.

Cannon A waves are characterized by a large upward deflection in the atrial waveform on the ECG, which is caused by the contraction of the atria against a closed tricuspid valve during ventricular systole. This results in a retrograde transmission of the atrial contraction wave, leading to an abnormal "A" wave on the ECG.

Cannon A waves can be a sign of increased atrial pressure or volume overload, and are often associated with conditions such as atrial fibrillation, atrial flutter, or ventricular pre-excitation. They may also be seen in patients with certain types of congenital heart defects or structural heart diseases.

Treatment for cannon A waves depends on the underlying cause and may include medications to control heart rhythm or surgical intervention to correct any structural abnormalities. Close monitoring and regular follow-up with a cardiologist are important for patients with cannon A waves to ensure proper management of their condition.