What are the risks of severe left atrial dilation?

Question

Hello doctor,

I have had atrial fibrillation (AF) for six years. I underwent direct current cardioversion (DCC), which restored sinus rhythm for 12 months, but I returned to AF six months ago.

My echocardiogram showed significant left atrial dilation (more than 200 percent of normal, with a volume of 180 ml compared to the normal 60 ml) and mild ventricular dilation. A 24-hour Holter monitor recorded heart rates ranging from tachycardia of up to 120 beats per minute to bradycardia with up to two seven-second pauses per night.

However, my condition was stable until about a year ago. My ejection fraction remains normal at 60 percent. I have scheduled an ablation procedure.

Could you please explain the risks associated with such severe dilations and what interventions might help restore normal heart structure and function?

Please help.

Thank you.

Answer 1

Hello,

Welcome to icliniq.com.

I have reviewed your query. While ablation can help prevent atrial fibrillation (AF), it is unlikely to restore the atrial size to its normal state. The primary risk associated with atrial dilation in AF is the formation of blood clots within the left atrial appendage, which can lead to embolism and increase the risk of stroke.

Typically, a transesophageal echocardiogram (TEE) is performed to rule out the presence of a thrombus before considering direct current cardioversion (DCC). When the left atrial size exceeds 1.77 inches (and some consider 2.16 inches as a critical threshold), anticoagulation therapy (blood thinners) is necessary to reduce the risk of stroke. In some instances, left atrial appendage closure devices or surgical removal of the appendage may be considered to decrease stroke risk further.

I recommend discussing these considerations with your consultant cardiologist, especially as you plan for the ablation.

I hope this information is helpful.

Thank you.