ACLS 2000

The Tachycardia Algorithms

胡為雄

Major New Concepts for the International Guidelines 2000

• Unstable tachycardias → Cardioversion

• Stable tachycardias– Making a specific rhythma diagnosis– Recognizing patients who have significantly impaired cardiac function ( EF < 40%, overt signs of heart failure )

Specific Rhythm Diagnosis Rationale

• Overuse of adenosine has often delayed more appropriate treatment

• Unpleasant side effects of adenosine, the possibility of worse rhythms, and a destablilization of heart rate and blood pressure

• Lidocaine is ineffective for termination of hemodynamically stable sustained VT

Specific Rhythm Diagnosis

• 12-lead ECG• Esophageal lead

~ Looking for AV dissociation ~

Specific Rhythm Diagnosis

• History– CAD, structural heart disease– accessory pathways, preexisting BBB, rate-

dependent BBB, previous aberrant rhythms

• Physical signs of AV dissociation– Irregular cannon A waves in the jugular venous

pulse– Varying intensity of S1– Beat – to – beat changes in SBP

Antiarrhythmics or Proarrhythmics

• Negative inotropic effects• Proarrhythmic effects

~ never use more than 1 agent unless absolutely necessary ~

Af/ AF with Normal Cardiac Function

Contro l rate Convert Rhythm ( < 48 hrs )

D C Cardiovers ionAm iddarone ( Ia)Ibutilide ( I Ia)F lec ain ide ( I Ia)P roc ainam ide ( I Ia)S otalo l ( I Ib)D is opyram ide (I Ib)

Calc ium bloc kers (I)£ ]- Bloc kers ( I )

Af / AF with Impaired Heart Function

Convert Rhythm ( < 48 hrs )D igoxin ( I Ib)D iltiazen ( I Ib)Am iodarone ( I Ib)

D C c ardiovers ionAm iodarone (I Ib)

Contro l Rate

Af/Af > 48 hrs or unknown duration

• Delayed cardioversionAnticoagulation x 3 wks

DC cardioversion

Anticoagulation x 4 more weeks

• Early cardiovesionBegin IV heparin at once

TEE to exclude atrial clot

Cardioversion within 24 hrs

Anticoagulation x 4 more weeks

Af / AF with WPW syndrome (< 48hrs)Normal Heart

D C c ardiovers ionAm iodarone (IIb)F lec ain ide (IIb)P roc ainam ide (IIb)P ropafenone ( I Ib)S otalo l ( I Ib)

Adenos ine ( I I I )-Bloc kers ( I I I )Calc ium bloc kers ( I I I )D igoxin ( II I )

Af / AF with WPW syndrome (< 48hrs)Impaired Heart

• DC cardioversion

• Amiodarone (IIb)

Af / AF with WPW syndrome( > 48 hrs or unknown )

• Anticoagulation

• DC cardioversion