- See:
A. Fib - Discussion: - atrial flutter may be assoc w/ sick sinus syndrome, hypoxia,
Pericarditis, valvular heart dz, and less commonly, acute myocardial infarction; - orginates in a single atrial ectopic focus; - flutter waves occur in rapid succession & are identical; - flutter waves have "saw tooth" appearance & do not have a flat baseline; - usually there are several "flutter waves" before each
QRS; - typically 2:1 or 4:1, or less often 3:1 or 5:1; - typically 2:1 in pts not on
Digoxin;
- Management: Stable A. flutter: - r/o
WPW as a predisposing cause; - as with
A.fib inital goal is rate control, rather than restoration of sinus; - mild symptoms, then attempt control rate w/ pharmological therapy first; - ventricular rate can be slowed with digitalis, verapamil, or Beta blocking agents; (the latter 2 may exacerbate CHF) - carotid massage may convert 2:1 block to 4:1 block; -
flutter waves may not be seen at 2:1 conduction, and this rhythm is often mistaken for PAT or sinus tachycardia; - carotid sinus massage to block just one beat to 3:1 conduction will clearly show
flutter waves; - once rate is controlled, pt is placed on
Type I antiarrhythmic agent such as
quinidine or procainamide to convert flutter; - these agents are not useful in the management of new onset atrial fib and
flutter, because they may increase rate of ventricular response; - these agents should be only used after complete digitalization; -
Unstable A. flutter (pt awake); - requires
Digoxin loading, but do not wait 30 min for IV
Digoxin to work; - consider either IV
B blocker or Ca blocker along w/ IV digitalization; -
Propanolol 0.5-1 mg IV q 5-8 min, then 10-20 mg PO q6hr -
Verapamil: 5 mg IV q10-15 min x 3 doses, then 80 mg PO q8hr -
Diltiazem - Unstable A. flutter (pt unconscious); - w/ hypotension, ischemic pain, or CHF, pt requires
Cardioversion; - is one of the easiest rhythms to convert to sinus rhythm; -
Cardioversion may require less than 50 Joules, but atrial
flutter often converts to
atrial fibrillation w/ low energy discharges (5-10 J);
- Resistant A. fib; - if 3 days of
quinidine does not convert the rhythm to NSR; - then hold
Digoxin for 24 hrs, and attempt DC conversion;
- Chronic A. flutter: - maintenance of NSR is unlikely if A. fib has continued for > 6 months; - DC conversion is unlikely to work - consider Anticoagulation: (see
Heparin) --------------------------------------
Preliminary report of the Stroke Prevention in Atrial Fibrillation Study. Original Articles: The Effect Of Low-Dose Warfarin On The Risk Of Stroke In Patients With Nonrheumatic Atrial Fibrillation. Kowey PR, Taylor JE, Rials SJ, Marinchak RA. Meta-analysis of the effectiveness of prophylactic drug therapy in preventing supraventricular arrhythmia early after coronary artery bypass grafting. Am J Cardiol 1992;69:963-5.
