What is sinus rhythm and sinus tachycardia on an ECG? Diagnostics
Normal sinus rhythm is the correct rhythm with a frequency of 60-100 per 1 min, originating from the sinus node. If the duration of a heartbeat cycle decreases with inhalation and increases with expiration, this condition is called phase (respiratory) sinus arrhythmia. If duration fluctuations do not depend on the rhythm of breathing – non-phase.
Sinus tachycardia is the result of the automatic discharge of a sinoatrial pacemaker with a frequency exceeding 100 contractions per minute. Characterized by the presence of normal sinus teeth P with a frequency usually not exceeding 130-140 per 1 min at rest, although it is possible and reaching 180-200 per 1 min, especially during exercise.
Sinus tachycardia is a normal physiological response to stress or emotional stress, or a reaction caused by drugs such as adrenaline, ephedrine, or atropine. Alcohol, caffeine or nicotine can also trigger sinus tachycardia. Constant sinus tachycardia usually indicates a latent disease (such as heart failure, pulmonary embolism, hypovolemia, or hypermetabolic state).
Vagal techniques (carotid sinus massage or Valsalva maneuver) help to distinguish sinus tachycardia from other supraventricular tachycardias (NCT). A gradual decrease in elevated frequency, followed by a return to it, is characteristic of sinus tachycardia. In contrast, carrying out vagal samples can abruptly cut off other NZhT or block conduction through the AV node.
Sinus tachycardia usually does not require special treatment; Therapy should be directed towards the underlying disease. B-adrenergic blockers are often effective in slowing the rhythm. However, first of all it is necessary to make sure that tachycardia is not compensatory, as in heart failure.