si·nu·a·tri·al block, S-A blocksinus block
blockade of the impulse leaving the sinus node before it can activate atrial muscle.
Synonym(s): sinoauricular block
Farlex Partner Medical Dictionary © Farlex 2012
si·nu·a·tri·al block, sinoatrial block (sin'yū-ā'trē-ăl blok, sī'nō-)
Blockade of an impulse leaving the sinuatrial node before it can activate atrial muscle or be propagated to the atrioventricular node. The condition is indicated on electrocardiography by the absence of some P waves.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012