* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Supraventricular Arrhythmias
Survey
Document related concepts
Heart failure wikipedia , lookup
Management of acute coronary syndrome wikipedia , lookup
Hypertrophic cardiomyopathy wikipedia , lookup
Cardiac surgery wikipedia , lookup
Cardiac contractility modulation wikipedia , lookup
Myocardial infarction wikipedia , lookup
Quantium Medical Cardiac Output wikipedia , lookup
Lutembacher's syndrome wikipedia , lookup
Ventricular fibrillation wikipedia , lookup
Electrocardiography wikipedia , lookup
Arrhythmogenic right ventricular dysplasia wikipedia , lookup
Transcript
Supraventricular Arrhythmias AAT.A FLUTTER.A FIB MEHDI BAKHSHI MSN PhD ICNS Definition • Rapid heart rhythm during which the electrical impulse propagates down the normal His Purkinje system similar to normal sinus rhythm • Distinct from ventricular tachycardia which only originates in the ventricles Mechanisms of Arrhythmia • Automaticity – Enhanced automaticity – Abnormal automaticity Mechanisms of Arrhythmia • Triggered Activity – Small depolarizations during or just after repolarization (phases 3 or 4) which can trigger a new depolarization. Mechanisms of Arrhythmia • Reentry-most common mechanism – Short circuit that forms between two “pathways” that are either anatomically or functionally distinct – Typically: • Path 1: Slow conduction, short refractory period • Path 2: Rapid conduction, long refractory period Reentry Panel A: Most impulses conduct down both pathways. Panel B: Unidirectional block, due to longer refractoriness in one pathway. Panel C: Potential to have reentry back up the previously refractory pathway Panel D: Reentry then can persist. Supraventricular Arrhythmias • Atrial arrhythmias (AT, AFL and AF) • Atrioventricular nodal reentrant tachycardia (AVNRT) and junctional ectopic tachycardia (JET) • Atrioventricular reentrant tachycardia (AVRT) Wolf-Parkinson-White Syndrome – Orthodromic AVRT – Antidromic AVRT SVT: Symptoms • May be variable – – – – – – Palpitations, chest pounding, neck pounding Weakness/malaise Dyspnea Chest pain Lightheadedness Near syncope/syncope • Symptoms usually abrupt in onset and termination • May have history of symptoms since childhood or have a positive FHx SVT: Physical Exam • In absence of tachycardia, usually normal • Rapid heart rate (150-250) – May be irregular or regular (mechanism) • BP may be low or with narrow pulse pressure • Neck veins may reveal cannon waves. Supraventricular Arrhythmias • Atrial arrhythmias (AT, AFL and AF) • Atrioventricular nodal reentrant tachycardia (AVNRT) and junctional ectopic tachycardia (JET) • Atrioventricular reentrant tachycardia (AVRT) Wolf-Parkinson-White Syndrome – Orthodromic AVRT – Antidromic AVRT Sinus Rhythm • Originates in sinus node (automaticity) • 50-100 bpm resting • Up to 200 bpm • Conduction through normal AV axis • P wave morphology reflects site of onset Atrial Tachycardia • Ectopic atrial focus – Reentrant, automatic or triggered • • • • 150-250 bpm 1:1 AV conduction Paroxysmal or “warm up” P wave morphology variable Focal Atrial Tachycardia RAA LAA SN * * * CT RAFW PV CSO IVC LAFW 20 yr woman with post-partum congestive heart failure I II III aVR aVL aVF V1 V2 V3 V4 V5 V6 Adenosine Injection I II III aVR aVL aVF V1 V2 V3 V4 V5 V6 Atrial Flutter • Reentrant circuit localized to the RA • 250-350 bpm • 2:1 or variable AV block • Classic “saw-tooth” P waves Activation on Halo Catheter Typical = Counterclockwise V1 II aVF TA 19,20 TA 9,10 TA 1,2 TA 1,2 TA 3,4 TA 5,6 TA 7,8 CS Os TA 9,10 TA 11,12 TA 13,14 TA 17,18 TA 19,20 CS Os Activation on Halo Catheter Atypical = Clockwise V1 II aVF TA 19,20 TA 9,10 TA 1,2 TA 1,2 TA 3,4 TA 5,6 TA 7,8 CS Os TA 9,10 TA 11,12 TA 13,14 TA 17,18 19,20 CS Os Atrial Fibrillation • Chaotic atrial rhythm due to multiple reentrant wavelets • 350-500 bpm • Ventricular rate irregular and rapid due to variable AV block • HTN, valvular dz., metabolic dz., CMP, Atrial Fibrillation • The rapid atrial activity results in: – Increased risk of thrombus formation and stroke – Rapid and irregular ventricular rate • The treatment is aimed at: – Decreasing the risk of stroke (coumadin, ASA) – Decreasing the ventricular rate (beta-blockers, calcium channel blockers, digoxin) – Restoring the rhythm to sinus (drug therapy, catheter ablation, surgical Maze) Atrial Fibrillation • Advantages of rhythm control: – Abolition of symptoms – Halting atrial enlargement – Improvement in left ventricular function and exercise capacity • Disadvantages of rhythm control: – Subjecting patients to drug therapy and/or procedure that might be associated with complications Atrial Fibrillation Treatment • In patients with minimal symptoms and normal left ventricular function: – Coumadin/ASA – Rate control (drugs, AVJ ablation + BV pacing) • In patients with significant symptoms and/or left ventricular dysfunction: – Coumadin/ASA – Rate control (drugs, AVJ ablation + BV pacing) – Rhythm control (anti-arrhytmic drugs, catheter ablation) Drug Therapy to Maintain Sinus Rhythm in Patients with Recurrent Paroxysmal or Persistent Atrial Fibrillation ACC/AHA/ESC Guidelines Heart Disease No (or minimal) Flecainide Propafenone Sotalol Yes Heart Failure CAD Amiodarone Dofetilide Sotalol Amiodarone, Dofetilide Disopyramide Procainamide Quinidine Consider nonpharmacological options Amiodarone Dofetilide Disopyramide Procainamide Quinidine Amiodarone Fuster et al. J Am Coll Cardiol. 2001;38:1231-1265. Hypertension LVH greater than or equal to 1.4 cm Yes No Flecainide Propafenone Amiodarone Dofetilide Sotalol Disopyramide, Procainamide, Quinidine Atrial Fibrillation Catheter Ablation Ablate PV potentials PV Isolation Pappone (circumferential LA ablation) Supraventricular Arrhythmias • Atrial arrhythmias (AT, AFL and AF) • Atrioventricular nodal reentrant tachycardia (AVNRT) and junctional ectopic tachycardia (JET) • Wolf-Parkinson-White Syndrome – Orthodromic AVRT – Antidromic AVRT – Atrial fibrillation with preexcitation AV Nodal Reentrant Tachycardia Morphology and location of P wave relative to QRS distinct 27 y.o with palpitations Pseudo R’ in V1 during tachycardia NSR AVNRT Junctional Ectopic Tachycardia Normal sinus rhythm Junctional tachycardia Supraventricular Arrhythmias • Atrial arrhythmias (AT, AFL and AF) • Atrioventricular nodal reentrant tachycardia (AVNRT) and junctional ectopic tachycardia (JET) • Atrioventricular reentrant tachycardia (AVRT) Wolf-Parkinson-White Syndrome – Orthodromic AVRT – Antidromic AVRT Wolff-Parkinson-White Syndrome • Second electrical connection exists between the atria and ventricles (accessory pathway) – Resemble atrial tissue – Results in a short PR and – Delta wave (pre-excitation) • Some AP conducts only retrograde (concealed) Arrythmias in WPW • The most common arrhythmia is orthodromic AV reentrant tachycardia (narrow QRS) • Less common are pre-excited tachcyardias (wide QRS) – – – – Antidromic AV reentrant tachycardia Atrial tachycardia/flutter with pre-excitation AVNRT with pre-excitation Atrial fibrillation with pre-excitation (most life threatening due to rapid ventricular response) Orthodromic AVRT Conduction down AV axis during tachycardia gives NARROW QRS complex Pre-excited Tachycardia Mechanisms AVRT AT AVNRT Conduction down AP during tachycardia gives WIDE QRS complex Atrial Fibrillation RF Ablation in WPW Supraventricular Arrhythmias • Atrial arrhythmias (AT, AFL and AF) • Atrioventricular nodal reentrant tachycardia (AVNRT) and junctional ectopic tachycardia (JET) • Atrioventricular reentrant tachycardia (AVRT) Wolf-Parkinson-White Syndrome – Orthodromic AVRT – Antidromic AVRT SUMMARY Mechanisms of SVT SP Atrial Tachycardia FP AVNRT AVRT Differential Diagnosis of NCT • Short RP – AVRT – AT – Slow-Slow AVNRT • Long RP – AT – Atypical AVNRT – PJRT • P buried in QRS – Typical AVNRT – AT – JET SUMMARY • Obtain a 12 lead ECG. The location of the P wave will dictate the differential diagnosis • If hemodynamically unstable (chest pain, heart failure, hypotension) CARDIOVERSION • If hemodynamically stable AV NODAL AGENT • Long term therapy depends on mechanism and can be conservative, pharmacologic or invasive • EP study often needed for definitive characterization of mechanism and can cure most SVTs with 90% success rate