• There is atrial fibrillation. No P waves are visible. The rhythm is irregularly irregular (random).
• There is the suggestion of right ventricular hypertrophy. Right axis deviation and deep S waves in the lateral leads. Another important feature of right ventricular hypertrophy not shown here is a dominant R wave in lead V1.

The combination of Atrial Fibrillation and Right Axis Deviation on the ECG suggests the possibility of mitral stenosis.