Atrial fibrillation is a common heart rhythm problem. More than 2 million Americans have this condition, which can cause palpitations, shortness of breath, fatigue and stroke.

Heart rhythm problems occur when the electrical impulses in your heart that coordinate your heartbeats don’t function properly, causing your heart to beat too fast, too slow or irregularly.

Here's a tidbit I stumbled upon. It looks like, according to MarketCharts.Com that MayoClinic.Com has been topped by RightHealth.Com in the standings as online medical sources.

MayoClinic.com has won a gold award in the Health Promotion/Disease &; Injury Prevention Web site category and an award for Best Site Structure &; Navigation in the spring 2004 World Wide Web ...