Clinical meaning
Atrial fibrillation results from multiple re-entrant wavelets or focal triggers (often from pulmonary veins) causing chaotic atrial electrical activity at 350-600 impulses/min. Loss of organized atrial contraction creates stasis in the left atrial appendage, forming thrombi that can embolize to the brain causing stroke.
Diagnosis & workup
Diagnostics & workup: - Order 12-lead ECG (absent P waves, irregularly irregular) - Order echocardiogram to assess valve function and LA size - Order thyroid function tests - Order CHA2DS2-VASc score calculation - Order HAS-BLED score for bleeding risk - Order continuous Holter monitor for paroxysmal AFib
Risk factors: - Hypertension (most common modifiable cause) - Heart failure - Valvular heart disease - Obstructive sleep apnea - Obesity - Excessive alcohol (holiday heart) - Hyperthyroidism - Advanced age