History

Fact Explanation
Asymptomatic Some patients are asymptomatic especially if the VF is non-sustained. VF is common in patients who are 45 to 75 years old.
History of coronary artery disease Patients with coronary artery disease and a history of myocardial infarction are at high risk of VF. Presence of cardiovascular risk factors (obesity, unhealthy dietary practices, physical inactivity, smoking) should also be looked for. [3,6]
Syncope Patients experience syncope or near syncope. Ventricular tachycardia causes rapid and unproductive ventricular contractions, leading to reduced cerebral perfusion and syncope. [2]
Sudden cardiac death VF is the commonest cause of sudden cardiac death. Sudden cessation of cardiac output leads to sudden death. Presence of family history of sudden cardiac death is also an important risk factor of VF. [1,2]
History of arrhythmia History of frequent ventricular ectopy, premature ventricular contractions or rapid ventricular tachycardia are risk factors of VF. Patients may develop VF after therapeutic cardioversion as well. [1,8]
History of cardiomyopathy Patients with dilated cardiomyopathy and hypertrophic cardiomyopathy are at risk of VF. [4,5,7]
History of myocarditis Myocarditis is another cause for the development of VF. [10]
History of structural heart diseases [9] Structural heart diseases, surgical repair of congenital heart diseases (Tetralogy of Fallot, Ebstein’s anomaly, single ventricle, transposition of the great arteries carry the highest risk of VF. Atrial septal defect and valvar pulmonary stenosis carry a small risk of VF. ) and valvular heart diseases can lead to VF. Sarcoidosis and other infiltrative heart diseases and right ventricular dysplasia are other causes of VF. [14]
History of ECG abnormalities Patients with ECG evidence of long QT syndrome, Wolff-Parkinson-White syndrome and Brugada syndrome can have VF. [11,12]
Triggering factors VF can be triggered by antiarrhythmic drugs, hypoxia, electrolyte imbalances, myocardial ischemia, cardioversion, and competitive ventricular pacing. [13]
References
  1. CIANCIULLI T. F., FERREIRO D. E., DAVOLOS D. G., SACCHERI M. C., LAX J. A., PREZIOSO H. A., VIDAL L. A.. Transesophageal Echocardiography During Ventricular Fibrillation. Circulation [online] December, 120(7):e43-e43 [viewed 09 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.109.853192
  2. PRYSTOWSKY ERIC N., PADANILAM BENZY J., JOSHI SANDEEP, FOGEL RICHARD I.. Ventricular Arrhythmias in the Absence of Structural Heart Disease. Journal of the American College of Cardiology [online] 2012 May, 59(20):1733-1744 [viewed 09 July 2014] Available from: doi:10.1016/j.jacc.2012.01.036
  3. GHEERAERT P. J., DE BUYZERE M. L., TAEYMANS Y. M., GILLEBERT T. C., HENRIQUES J. P.S., DE BACKER G., DE BACQUER D.. Risk factors for primary ventricular fibrillation during acute myocardial infarction: a systematic review and meta-analysis. European Heart Journal [online] 2006 September, 27(21):2499-2510 [viewed 09 July 2014] Available from: doi:10.1093/eurheartj/ehl218
  4. ELLIOTT PERRY M, SHARMA SANJAY, VARNAVA AMANDA, POLONIECKI JAN, ROWLAND EDWARD, MCKENNA WILLIAM J. Survival after cardiac arrest or sustained ventricular tachycardia in patients with hypertrophic cardiomyopathy. Journal of the American College of Cardiology [online] 1999 May, 33(6):1596-1601 [viewed 09 July 2014] Available from: doi:10.1016/S0735-1097(99)00056-X
  5. VON OLSHAUSEN K, SCHäFER A, MEHMEL HC, SCHWARZ F, SENGES J, KüBLER W. Ventricular arrhythmias in idiopathic dilated cardiomyopathy. Br Heart J [online] 1984 Feb, 51(2):195-201 [viewed 09 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC481483
  6. SAYER J W. Prognostic implications of ventricular fibrillation in acute myocardial infarction: new strategies required for further mortality reduction. [online] 2000 September, 84(3):258-261 [viewed 09 July 2014] Available from: doi:10.1136/heart.84.3.258
  7. ASHWATH ML, SOGADE FO. Focal origin of ventricular fibrillation in a patient with ischemic cardiomyopathy. J Natl Med Assoc [online] 2004 Sep, 96(9):1228-1231 [viewed 09 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2568466
  8. CRIJNS HJ, WIESFELD AC, POSMA JL, LIE KI. Favourable outcome in idiopathic ventricular fibrillation with treatment aimed at prevention of high sympathetic tone and suppression of inducible arrhythmias. Br Heart J [online] 1995 Oct, 74(4):408-412 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC484048
  9. AYDIN A, OKMEN E, ERDINLER I, SANLI A, CAM N. Adrenal Adenoma Presenting with Ventricular Fibrillation Tex Heart Inst J [online] 2005, 32(1):85-87 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC555832
  10. FIDDLER GI, CAMPBELL RW, POTTAGE A, GODMAN MJ. Varicella myocarditis presenting with unusual ventricular arrhythmias. Br Heart J [online] 1977 Oct, 39(10):1150-1153 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC483385
  11. LIM SM, PAK HN, LEE MH, KIM SS, JOUNG B. Fever-Induced QTc Prolongation and Ventricular Fibrillation in a Healthy Young Man Yonsei Med J [online] 2011 Nov 1, 52(6):1025-1027 [viewed 10 July 2014] Available from: doi:10.3349/ymj.2011.52.6.1025
  12. BREMBILLA-PERROT B. Electrophysiological evaluation of Wolff-Parkinson-White Syndrome Indian Pacing Electrophysiol J [online] , 2(4):143-152 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1557416
  13. PASQUIé JL. May Fever Trigger Ventricular Fibrillation? Indian Pacing Electrophysiol J [online] , 5(2):139-145 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1502075
  14. WALSH E. P., CECCHIN F.. Arrhythmias in Adult Patients With Congenital Heart Disease. Circulation [online] 2007 January, 115(4):534-545 [viewed 13 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.105.592410

Examination

Fact Explanation
Level of consciousness Most patients are unconscious at the time of presentation. [2]
Pulse In the emergency setting patient can be pulseless. More than ten seconds should not be spent trying to palpate the pulse because life saving measures should be immediately carried out. [1,3]
Blood pressure Hypotension is commonly observed. This is due to diminished cardiac output which occurs secondary to unproductive ventricular contractions.
Cardiac auscultation No heart sounds are audible during a VF. This is due to uncoordinated atrial and ventricular contractions. [3]
References
  1. Part 7.2: Management of Cardiac Arrest. Circulation [online] 2005 November, 112(24_suppl):IV-58-IV-66 [viewed 13 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.105.166557
  2. BODDICKER K. A.. Hypothermia Improves Defibrillation Success and Resuscitation Outcomes From Ventricular Fibrillation. Circulation [online] 2005 June, 111(24):3195-3201 [viewed 13 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.104.492108
  3. SCHWARTZ S. P., HALLINGER L., IMPERIALLI A.. Transient Ventricular Fibrillation: IV. The Effects of Procaine Amide on Patients with Transient Ventricular Fibrillation during Established Auriculoventricular Dissociation. Circulation [online] 1952 August, 6(2):193-200 [viewed 13 July 2014] Available from: doi:10.1161/01.CIR.6.2.193

Differential Diagnoses

Fact Explanation
Ventricular tachycardia VT is another cause for broad QRS complexes. But the QRS complexes are regular and the ventricular rate is more than 100 beats/minute in VT. [3]
Aortic stenosis Aortic stenosis may lead to acute coronary syndrome and development of VF.
Cardiomyopathy Hypertrophic cardiomyopathy can cause ventricular tachycardia which later develops in to ventricular fibrillation. [4]
Ebstein anomaly Ebstein anomaly is a rare congenital heart disease. The tricuspid valve is malformed and the right ventricle is partially incorporated in to the right atrium. [5]
Long QT syndrome An abnormality in the ion channels in the ventricles causes slow transmission of the signals for ventricular repolarization, leading to long QT interval. This can propagate into VF. [6]
Lown-Ganong-Levine syndrome An abnormal atrioventricular node transmits most of the atrial impulses to the ventricle leading to rapid ventricular excitation and VF. [7]
Myocardial infarction Myocardial infarction can lead to VF. [8]
Torsade de pointes Torsade de pointes is one of the polymorphic ventricular tachycardia. ECG shows marked prolongation of the QT interval. [2]
Wolff-Parkinson-White syndrome In Wolff-Parkinson-White syndrome there is an aberrant conduction pathway connecting the atria and the ventricle leading to rapid ventricular rate. VF is one of the rhythm abnormalities associated with Wolff-Parkinson-White syndrome. [8]
Pulseless electrical activity Pulseless electrical activity can cause sudden cardiac death, commonly seen in elders and in females. [1]
References
  1. SADEGHI R, ADNANI N, SOHRABI MR, ALIPOUR PARSA S. Risk of sudden cardiac death ARYA Atheroscler [online] 2013 Sep, 9(5):274-279 [viewed 09 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3845694
  2. TRAPPE HJ. Treating critical supraventricular and ventricular arrhythmias J Emerg Trauma Shock [online] 2010, 3(2):143-152 [viewed 09 July 2014] Available from: doi:10.4103/0974-2700.62114
  3. HEBBAR AK, HUESTON WJ. Management of common arrhythmias: Part II. Ventricular arrhythmias and arrhythmias in special populations. Am Fam Physician [online] 2002 Jun 15, 65(12):2491-6 [viewed 13 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/12086238
  4. SAUMAREZ R. C., CAMM A. J., PANAGOS A., GILL J. S., STEWART J. T., DE BELDER M. A., SIMPSON I. A., MCKENNA W. J.. Ventricular fibrillation in hypertrophic cardiomyopathy is associated with increased fractionation of paced right ventricular electrograms. Circulation [online] 1992 August, 86(2):467-474 [viewed 13 July 2014] Available from: doi:10.1161/01.CIR.86.2.467
  5. ATTENHOFER JOST C. H., CONNOLLY H. M., DEARANI J. A., EDWARDS W. D., DANIELSON G. K.. Ebstein's Anomaly. Circulation [online] 2006 December, 115(2):277-285 [viewed 13 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.106.619338
  6. HUNTER J. D., SHARMA P., RATHI S.. Long QT syndrome. Continuing Education in Anaesthesia, Critical Care & Pain [online] 2008 February, 8(2):67-70 [viewed 13 July 2014] Available from: doi:10.1093/bjaceaccp/mkn003
  7. OMETTO R, THIENE G, CORRADO D, VINCENZI M, ROSSI L. Enhanced A-V nodal conduction (Lown-Ganong-Levine syndrome) by congenitally hypoplastic A-V node. Eur Heart J [online] 1992 Nov, 13(11):1579-84 [viewed 13 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/1464347
  8. SAYER J, ARCHBOLD R, WILKINSON P, RAY S, RANJADAYALAN K, TIMMIS A. Prognostic implications of ventricular fibrillation in acute myocardial infarction: new strategies required for further mortality reduction Heart [online] 2000 Sep, 84(3):258-261 [viewed 13 July 2014] Available from: doi:10.1136/heart.84.3.258
  9. KLEIN GEORGE J., BASHORE THOMAS M., SELLERS T. D., PRITCHETT EDWARD L. C., SMITH WILLIAM M., GALLAGHER JOHN J.. Ventricular Fibrillation in the Wolff-Parkinson-White Syndrome. N Engl J Med [online] 1979 November, 301(20):1080-1085 [viewed 13 July 2014] Available from: doi:10.1056/NEJM197911153012003

Investigations - for Diagnosis

Fact Explanation
ECG [2,3] There are few characteristic features of the ECG. The waves are bizarre and irregular. The QRS complexes and P waves can not be clearly identified and the baseline is irregular.
Exercise ECG Exercise induced arrhythmia can be detected by the exercise ECG. [4]
Holter monitoring [5] Holter monitoring is indicated if VF is strongly suspected and if the ECG is normal.
Echocardiography Reduced ejection fraction and abnormal left ventricular wall motion predicts the risk of VF. Transesophageal echocardiogram demonstrates irregular ventricular oscillations. [1]
References
  1. CIANCIULLI T. F., FERREIRO D. E., DAVOLOS D. G., SACCHERI M. C., LAX J. A., PREZIOSO H. A., VIDAL L. A.. Transesophageal Echocardiography During Ventricular Fibrillation. Circulation [online] December, 120(7):e43-e43 [viewed 09 July 2014] Available from: doi:10.1161/​CIRCULATIONAHA.109.853192
  2. PRYSTOWSKY ERIC N., PADANILAM BENZY J., JOSHI SANDEEP, FOGEL RICHARD I.. Ventricular Arrhythmias in the Absence of Structural Heart Disease. Journal of the American College of Cardiology [online] 2012 May, 59(20):1733-1744 [viewed 09 July 2014] Available from: doi:10.1016/j.jacc.2012.01.036
  3. TRAPPE HJ. Treating critical supraventricular and ventricular arrhythmias J Emerg Trauma Shock [online] 2010, 3(2):143-152 [viewed 09 July 2014] Available from: doi:10.4103/0974-2700.62114
  4. YOUNG D. Z., LAMPERT S., GRABOYS T. B., LOWN B.. Safety of maximal exercise testing in patients at high risk for ventricular arrhythmia. Circulation [online] 1984 August, 70(2):184-191 [viewed 12 July 2014] Available from: doi:10.1161/01.CIR.70.2.184
  5. KATRITSIS D. Nonsustained ventricular tachycardia: where do we stand?. European Heart Journal [online] 2004 July, 25(13):1093-1099 [viewed 12 July 2014] Available from: doi:10.1016/j.ehj.2004.03.022

Investigations - Followup

Fact Explanation
ECG VF can recur even after treatment, so ECG monitoring is necessary. [1]
References
  1. PRYSTOWSKY ERIC N., PADANILAM BENZY J., JOSHI SANDEEP, FOGEL RICHARD I.. Ventricular Arrhythmias in the Absence of Structural Heart Disease. Journal of the American College of Cardiology [online] 2012 May, 59(20):1733-1744 [viewed 09 July 2014] Available from: doi:10.1016/j.jacc.2012.01.036

Management - General Measures

Fact Explanation
Basic life support Cardiopulmonary resuscitation should be immediately started. Assessment of the airway, breathing and circulation should be carried out but it should not delay cardiac defibrillation. Oxygen should be delivered via a face mask and if the patient is unconscious immediate intubation and bag and mask ventilation is necessary. Patient should be connected to a cardiac monitor. Administration of intravenous fluid is considered if necessary. Some patients with severe cardiac failure and cardiogenic shock may require mechanical cardiac support. Intravenous adrenaline is also helpful because it is a vasoconstrictor and increases the cerebral perfusion. [3] Patients should be given intensive care because of the high risk of recurrence. [1]
Correct any electrolyte imbalances Electrolyte imbalance especially hypomagnesaemia and hypokalemia can precipitate arrhythmia and it is reversible. If present magnesium supplementation should be done. [1,2]
References
  1. TRAPPE HJ. Treating critical supraventricular and ventricular arrhythmias J Emerg Trauma Shock [online] 2010, 3(2):143-152 [viewed 09 July 2014] Available from: doi:10.4103/0974-2700.62114
  2. AYDIN A, OKMEN E, ERDINLER I, SANLI A, CAM N. Adrenal Adenoma Presenting with Ventricular Fibrillation Tex Heart Inst J [online] 2005, 32(1):85-87 [viewed 10 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC555832
  3. MAGNANI J. W.. Myocarditis: Current Trends in Diagnosis and Treatment. Circulation [online] 2006 February, 113(6):876-890 [viewed 12 July 2014] Available from: doi:10.1161/CIRCULATIONAHA.105.584532

Management - Specific Treatments

Fact Explanation
Defibrillation Defibrillation is the most important management option in managing VF. Early defibrillation is lifesaving in emergencies. Ideally it should be done within two minutes in the emergency department. The two paddles should be kept over the right upper sternum and over the cardiac apex or over the tip of the left scapula and anterior left chest. [3]
Implantation of defibrillator [1] Insertion of internal cardioverter-defibrillator (ICD) is recommended in all patients with VF even in the absence of non-sustained VF. [1,2]
Catheter ablation Catheter ablation of the premature ventricular contraction triggers are useful in some patients. [1]
Medical management Isoproterenol and quinidine are used in the acute and long term management of VF respectively. Beta blockers are proven to reduce the risk of recurrence of VF. Amiodarone is the drug of choice if defibrillation fails. [1,3,4]
References
  1. PRYSTOWSKY ERIC N., PADANILAM BENZY J., JOSHI SANDEEP, FOGEL RICHARD I.. Ventricular Arrhythmias in the Absence of Structural Heart Disease. Journal of the American College of Cardiology [online] 2012 May, 59(20):1733-1744 [viewed 09 July 2014] Available from: doi:10.1016/j.jacc.2012.01.036
  2. MITTAL SUNEET, HAO STEVEN C, IWAI SEI, STEIN KENNETH M, MARKOWITZ STEVEN M, SLOTWINER DAVID J, LERMAN BRUCE B. Significance of inducible ventricular fibrillation in patients with coronary artery disease and unexplained syncope. Journal of the American College of Cardiology [online] 2001 August, 38(2):371-376 [viewed 09 July 2014] Available from: doi:10.1016/S0735-1097(01)01379-1
  3. TRAPPE HJ. Treating critical supraventricular and ventricular arrhythmias J Emerg Trauma Shock [online] 2010, 3(2):143-152 [viewed 09 July 2014] Available from: doi:10.4103/0974-2700.62114
  4. EXNER DEREK V., REIFFEL JAMES A., EPSTEIN ANDREW E., LEDINGHAM ROBERT, REITER MICHAEL J., et al. Beta-blocker use and survival in patients with ventricular fibrillation or symptomatic ventricular tachycardia: the antiarrhythmics versus implantable defibrillators (AVID) trial. Journal of the American College of Cardiology [online] 1999 August, 34(2):325-333 [viewed 09 July 2014] Available from: doi:10.1016/S0735-1097(99)00234-X