PHRM3011 Lecture Notes - Lecture 7: Vasoconstriction, Antiplatelet Drug, Diltiazem
Document Summary
The normal rhythmical contraction of the cardiac atria are replaced by rapid irregular twitchings of the muscular wall that cause the ventricles to response irregularly . Av node filters out the rapid irregular twitching from atria but still causes irregular depolarisation = irregular ventricular rate. Multiple re-entrant pathways rapid atria rate of 400bpm. Ventricles slower: irregular in af 160-180bpm, regular in af 150bpm increased p waves. Paroxysmal: reverts in 24-48 hrs without any intervention (comes and goes) Permanent or chronic: events after interventions. Treatment conversion to and maintain sinus rhythm (normal) If had for more that 48hrs could have high chance of blood clot in heart, use anticoagulant (warfarin) to prevent stroke 3 weeks before cardioversion and. Dc shock: 90% effective, even if af>7 days, need to sedate pt. Pharmacological: 47-84% success (small studies, oral or iv, better if af<7 days. Flecainide iv or oral (class 1, avoid in structural heart disease and heart failure)
