ECG PR interval

Introduction

ECG segment joining P wave & the QRS complex, corresponding to the period of conduction through the AV node.

Clinical significance

• Normal: 120-200 msec

• PR segment elevation
  • atrial infarction

• PR segment depression
  • acute pericarditis

• shortened PR interval
  • WPW syndrome
  • AV junctional rhythm
  • HTN (occasional)
  • Lown-Ganong-Levine syndrome
  • glycogen storage disease
  • Fabry's disease
  • pheochromocytoma

• prolonged PR interval
  • AV block (also see 1st degree AV block)
    • endocarditis with extension in the aortic valve annulus & formation of a pericardial abscess
    • endocarditis with acute aortic insufficiency increases left ventricular filling pressure diminishing cardiac output resulting in pulmonary edema & systemic hypotension
  • hyperthyroidism
  • normal variation

More general terms

• electrocardiogram feature

Additional terms

• electrocardiogram (ECG, EKG)