Changes

===Small Animals===

===Small Animals===

Patients with primary atrial fibrillation are usually asymptomatic, but may present with exercise intolerance.

Patients with primary atrial fibrillation are usually asymptomatic. However, there may be signs of haemodynamic compromise due to the rapid heart rate and a loss of atrial contribution to ventricular filling; which would usually account for up to 20% of cardiac output.  

Other signs are generally related to the underlying disease process or [[:Category:Heart Failure|'''congestive heart failure''']]. There may be a history of coughing, dyspnoea, tachypnoea, exercise intolerance, episodes of syncope.

Other signs are generally related to the underlying disease process or [[:Category:Heart Failure|'''congestive heart failure''']]. There may be a history of coughing, dyspnoea, tachypnoea, exercise intolerance, episodes of syncope.