Simplified origins of the QT interval. Some say Einthoven chose PQRST because it’s the middle of the alphabet and allowed for extra letters to be added later – like the U wave. Others say it was because Waller (the first person to do an ECG) had used A and B for the ventricular contractions and so when Einthoven found the atrial deflections he used P. Some say P is for presystolic other that he was copying Descartes’ use of the letter P to designate a point on a curve.
Either way… we could have well be talking about Long BD Syndrome which doesn’t quite have the same ring to it.
The Long Cutie 