15 High Yield EKG

  • P
  • QRS
  • Intervals
  • ST

P

  • regular: spacing between QRS same

QRS

Intervals

  • atheletes (high vagal tones) and beta blockers prolong PR

ST

Practice 1

  • easily identifiable P
  • upright P in II, III, AVF: normal sinus P
  • QRS: regular
  • QRS: narrow
  • PR: less than 1 block
  • QT: less than half
  • ST: no significant depression, elevation

Practice 2

  • P: upright in II, III, AVF, normal sinus P
  • RR: regular QRS
  • QRS: wide in V1, upright QRS in V1 RBBB
  • PR: not prolonged
  • QT: less than 1/2
  • ST: T inversion in V1, normal in RBBB

Practice 2

  • P upright in II, III, AVF, sinus
  • QRS wide, negative V1, LBBB
  • peaked T and ST elevation in V1-3: common
  • T inversion 1, L, V5, V6: normal in LBBB

Practice 4

  • no clear P waves, afib
  • irregularly irregular: QRS closer in some, farther apart in others

Practice 5

  • sawtooth, aflut

Practice 6

  • ventricle contracts on its own

  • buried P waves at different rate as QRS (AV dissociation)

VFib

  • top: VFIB, cardiac arrest

PAC, PVC

  • top: early wide QRS, PVC, something stimulated ventricles to contract on its own (high catecholamines, infection, surgery)
  • bottom: early narrow QRS with compensatory pause after