WPW syndrome is caused by:

Answer is B (Right sided accessory pathway) Wolf Parkinson White syndrome is caused by the presence of on additional / accessory pathway (connection) between the atria and ventricle. The acessary pathway (called bundle of Kent) may be present as a connection between the left atrium and left ventricle (Left sided) or as a connection between the right atrium and right ventricle (Right sided). Pre excitation resulting from left sided accessory pathways is called Type A Pre-excitation Pre excitation resulting from right sided accessory pathway is called Type B Pre-excitation The most common accessary pathways leading to pre-excitation syndromes (WPW) are left sided (connecting left atrium to left ventricle).