Supraventricular tachycardia. Occasional nuisance or frequent threat?

Supraventricular tachycardias (SVTs) are common and are widely regarded as a nuisance. They are often repetitive and persistent, and cause more upset than is currently acknowledged although only rarely do they threaten life. Surprisingly, they are ill-defined. A modern approach to SVT requires an accurate diagnosis and a readiness to abandon obsolete therapies in favour of effective new strategies, whether pharmacological or ablative.