Concertina effect in WPW syndrome is varying QRS width in WPW syndrome due to varying degrees of pre-excitation. More the pre-excitation, shorter the PR and wider the QRS.
Differentiation of late diastolic ventricular ectopic from intermittent pre-excitation: PJ interval constant in WPW syndrome, can vary in late diastolic VPC
In which situation is AF likely to cause VF?
1. Associated with hyperthyroidism
2. Associated with hypothyroidism
3. When associated with WPW syndrome
4. Associated with MS
