AVNRT medical therapy: Difference between revisions

Jump to navigation Jump to search
No edit summary
Line 4: Line 4:


==Overview==
==Overview==
Medical therapy can be initiated with drugs that slow AV nodal conduction.
Medical therapy can be initiated with drugs that slow AV nodal conduction:


==First Line Therapy==
====  First Line Therapy ====
===[[Adenosine]]===


===[[Beta blocker]]s===
=====  [[Adenosine]] =====
Adenosine is generally considered first line therapy for AVNRT.


==Second Line Therapy==
Treatment of AVNRT with adenosine can be complicated by:
Numerous other antiarrhythmic drugs may be effective if the more commonly used medications have not worked; these include [[flecainide]] or [[amiodarone]]. Both adenosine and beta blockers may cause [[Bronchoconstriction|tightening of the airways]], and are therefore used with caution in people who are known to have [[asthma]].  Calcium channel blockers should be avoided if there is a [[wide complex tacycardia]] and the diagnosis of AVNRT is not clearly established in so far as [[calcium channel blockers]] should be avoided in [[ventricular tachycardia]].  If the diagnosis of AVNRT is established, then non-dihydropyridine [[calcium channel blocker]]s (such as [[verapamil]]) may be administered to terminate the rhythm is other agents are not effective.
*The development of [[shortness of breath]] due to [[bronchospasm]]
*In some cases there can be [[asystole]] which is transient given the short [[half life]] of adenosine
*[[Atrial fibrillation]] may be induced by [[adenosine]] administration
*[[Ventricular fibrillation]] is rarely induced by adenosine. When it does occur it is due to block of the [[AV node]] with rapid antegrade conduction of [[atrial fibrillation]] down the bypass tractIt is for this reason that [[defibrillation]] equipment be available.
*Adenosine should not be used in [[heart transplant]] patients
*[[Dipyridamole]] may potentiate the effect of [[adenosine]]
*[[Theophylline]] may reduce the effectiveness of [[adenosine]]
 
Administration:
*Place a large bore (18 gauge and larger) intravenous line
*The initial dose is 6 mg and this should be followed a saline flush with elevation of the arm to assure that the drug is infused
*If this is not effective, then 12 mg or 18 mg of [[adenosine]] can be admininistered
 
=====[[Beta blocker]]s=====
A short acting beta-blocker such as [[esmolol]] (half life of 8 minutes) can be used to terminate an episode of AVNRT.  Longer acting beta-blockers such as [[atenolol]], [[metoprolol]], and [[propranolol]] can also be used to reduce the risk of recurrent episodes.  [[Atenolol]] may be preferable among patients with [[bronchospasm]] as it selectively blocks [[beta-1 receptors]] with little effect on [[beta- 2 receptors]].
==References==
==References==
{{Reflist|2}}
{{Reflist|2}}

Revision as of 21:08, 9 September 2012

AVNRT Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating AVNRT from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diaagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography and Ultrasound

CT Scan

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Overview

Medical Treatment

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Case Studies

Case #1

AVNRT medical therapy On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of AVNRT medical therapy

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on AVNRT medical therapy

CDC on AVNRT medical therapy

AVNRT medical therapy in the news

Blogs on AVNRT medical therapy

Directions to Hospitals Treating AVNRT

Risk calculators and risk factors for AVNRT medical therapy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Medical therapy can be initiated with drugs that slow AV nodal conduction:

First Line Therapy

Adenosine

Adenosine is generally considered first line therapy for AVNRT.

Treatment of AVNRT with adenosine can be complicated by:

Administration:

  • Place a large bore (18 gauge and larger) intravenous line
  • The initial dose is 6 mg and this should be followed a saline flush with elevation of the arm to assure that the drug is infused
  • If this is not effective, then 12 mg or 18 mg of adenosine can be admininistered
Beta blockers

A short acting beta-blocker such as esmolol (half life of 8 minutes) can be used to terminate an episode of AVNRT. Longer acting beta-blockers such as atenolol, metoprolol, and propranolol can also be used to reduce the risk of recurrent episodes. Atenolol may be preferable among patients with bronchospasm as it selectively blocks beta-1 receptors with little effect on beta- 2 receptors.

References