Ventricular fibrillation medical therapy

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

Overview

In the event of cardiac arrest due to ventricular fibrillation, the immediate implementation of ACLS guidelines is indicated. When a sudden cardiac arrest occurs, immediate CPR is a vital link in the chain of survival. Another important link is early defibrillation, which has improved greatly with the widespread availability of AEDs. It often starts with analysing patient’s heart rhythms with a manual defibrillator.

Medical Therapy

Defibrillation

Electric Defibrillator

The condition can often be reversed by the electric discharge of direct current from a defibrillator. Although a defibrillator is designed to correct the problem, and its effects can be dramatic, it is not always successful.

Implantable Electric Defibrillator

In patients at high risk of ventricular fibrillation, the use of an implantable cardioverter defibrillator has been shown to be beneficial.

Precordial Thump

If no defibrillator is available, a precordial thump can be delivered at the onset of VF for a small chance to regain cardiac function. However, research has shown that the precordial thump releases no more than 30 joules of energy. This is far less than the 200–360 J typically used to bring about normal sinus rhythm. Consequently, in the hospital setting, this treatment is not used.

Antiarrhythmic Agents

Antiarrhythmic agents like amiodarone or lidocaine can help, but, unlike atrial fibrillation, ventricular fibrillation rarely reverses spontaneously in large adult mammals. Drug therapy with antiarrhythmic agents in ventricular fibrillation does not replace defibrillation and is not the first priority, but is sometimes needed in cases where initial defibrillation attempts are not successful.

Medications that may be used include:

Amiodarone, 300 mg bolus IV for VF/pulseless VT arrest and then 1 mg/min for 6 h.
- Common side effects include hypotension, bradycardia, atrioventricular block, Torsade de point, corneal microdeposits, thyroid abnormalities, and pulmonary fibrosis.
Lidocaine, 1 mg/kg bolus IV and then 1–3 mg/min 1–1.5 mg/kg.
- Common side effects include bradycardia, hemodynamic collapse, atrioventricular block, and sinus arrest.
Quinidine, 800 mg in 50 mL IV infused at 50 mg/min.
- Common side effects include syncope, Torsade de point, atrioventricular block.
Sotalol, 75 mg IV.
- Common side effects include bradycardia, hypotension, heart failure, and syncope.

Contraindicated medications

Ventricular fibrillatioins is considered an absolute contraindication to the use of the following medications:

2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death^[1]

Acute Management of Ventricular Fibrillation

Class I
“ In patients with hemodynamically unstable VA that persist or recur after a maximal energy shock, intravenous amiodarone should be administered to attempt to achieve a stable rhythm after further defbrillation. (Level of Evidence: A)”

Class IIa
“In patients with symptomatic, non–lifethreatening VA, treatment with a beta blocker is reasonable. (Level of Evidence: C)”

Class IIb
“In patients with VT/VF storm in whom a beta blocker, other antiarrhythmic medications, and catheter ablation are ineffective, not tolerated, or not possible, cardiac sympathetic denervation may be reasonable.(Level of Evidence: C)”

Ventricular Fibrillation in Specific Conditions

Class I
“In patients with polymorphic VT or VF with ST-elevation MI, angiography with emergency revascularization is recommended. (Level of Evidence: B)”

Class IIa
“In patients with a witnessed cardiac arrest due to VF or polymorphic VT that is unresponsive to CPR, defbrillation, and vasopressor therapy, intravenous lidocaine can be benefcial.(Level of Evidence: B)”
“In patients with a recent MI who have VT/VF that repeatedly recurs despite direct current cardioversion and antiarrhythmic medications (VT/VF storm), an intravenous beta blocker can be useful.(Level of Evidence: B)”

Class III (No Benefit)
” In patients with refractory VF not related to torsades de pointes, administration of intravenous magnesium is not benefcial.(Level of Evidence: C)”
“In patients with incessant VT or VF, an ICD should not be implanted until suffcient control of the VA is achieved to prevent repeated ICD shocks. (Level of Evidence: C)”

References

↑ Al-Khatib, Sana M.; Stevenson, William G.; Ackerman, Michael J.; Bryant, William J.; Callans, David J.; Curtis, Anne B.; Deal, Barbara J.; Dickfeld, Timm; Field, Michael E.; Fonarow, Gregg C.; Gillis, Anne M.; Granger, Christopher B.; Hammill, Stephen C.; Hlatky, Mark A.; Joglar, José A.; Kay, G. Neal; Matlock, Daniel D.; Myerburg, Robert J.; Page, Richard L. (2018). “2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death”. Circulation. 138 (13). doi:10.1161/CIR.0000000000000549. ISSN 0009-7322.

Template:WH Template:WS

[Al-KhatibStevenson2018-1] Al-Khatib, Sana M.; Stevenson, William G.; Ackerman, Michael J.; Bryant, William J.; Callans, David J.; Curtis, Anne B.; Deal, Barbara J.; Dickfeld, Timm; Field, Michael E.; Fonarow, Gregg C.; Gillis, Anne M.; Granger, Christopher B.; Hammill, Stephen C.; Hlatky, Mark A.; Joglar, José A.; Kay, G. Neal; Matlock, Daniel D.; Myerburg, Robert J.; Page, Richard L. (2018). “2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death”. Circulation. 138 (13). doi:10.1161/CIR.0000000000000549. ISSN 0009-7322.

[1]