Anomalous atrioventricular excitation

Cardiovascular

Clinicals - History

Fact Explanation
Palpitations Anomalous atrioventricular excitation develops due to the presence of an accessory pathway between the atria and the ventricles which is a congenital anomaly (Wolff-parkinson-white syndrome). The atria and ventricles are usually separated from each other by fibrous rings and the only connection lies at the AV node. The accessory pathway leads to development of tachyarrhythmias. These are perceived by the patient as abnormal or fast heart beats. Palpitations
Anomalous atrioventricular excitation develops due to the presence of an accessory pathway between the atria and the ventricles which is a congenital anomaly (Wolff-parkinson-white syndrome). The atria and ventricles are usually separated from each other by fibrous rings and the only connection lies at the AV node. The accessory pathway leads to development of tachyarrhythmias. These are perceived by the patient as abnormal or fast heart beats.
Dizziness and Syncope Due to diminished blood flow to the cerebrum. Cardiac output is reduced due to rapid heart rate. Dizziness and Syncope
Due to diminished blood flow to the cerebrum. Cardiac output is reduced due to rapid heart rate.
Chest discomfort/ chest pain The cardiac arrhythmia may be perceived as chest discomfort. Chest discomfort/ chest pain
The cardiac arrhythmia may be perceived as chest discomfort.
Breathing difficulty Due to pulmonary congestion. Anxiety may also contribute to breathing difficulty. Breathing difficulty
Due to pulmonary congestion. Anxiety may also contribute to breathing difficulty.
Incidental finding The condition may be identified as an incidental finding on electrocardiography. Incidental finding
The condition may be identified as an incidental finding on electrocardiography.
The patient may present with cardiac arrest / sudden cardiac death Due to an acute onset catastrophic dysrhythmia. The patient may present with cardiac arrest / sudden cardiac death
Due to an acute onset catastrophic dysrhythmia.

Clinicals - Examination

Fact Explanation
Physical examination is usually normal Majority of patients will have no abnormality on examination of the cardiovascular system. Physical examination is usually normal
Majority of patients will have no abnormality on examination of the cardiovascular system.
Cardiovascular system examination : tachycardia The pulse rate would be elevated. The patient can develop supraventricular tachycardia, atrial fibrillation or atrial flutter leading to a rapid ventricular rate. Cardiovascular system examination : tachycardia
The pulse rate would be elevated. The patient can develop supraventricular tachycardia, atrial fibrillation or atrial flutter leading to a rapid ventricular rate.
Cardiovascular system examination : Irregularly irregular pulse In atrial fibrillation the pulse rhythm is irregular. In other atrial tachycardias the rhythm would be regular. Cardiovascular system examination : Irregularly irregular pulse
In atrial fibrillation the pulse rhythm is irregular. In other atrial tachycardias the rhythm would be regular.
Cardiovascular system examination : Variable pulse volume Different cardiac outputs at each ventricular contraction results in a change in the pulse volume. The ventricular filling is affected due to the arrhythmia. Cardiovascular system examination : Variable pulse volume
Different cardiac outputs at each ventricular contraction results in a change in the pulse volume. The ventricular filling is affected due to the arrhythmia.
Cardiovascular system examination : On auscultation variable intensity of the first heart sound In atrial fibrillation the irregular atrial activity results in variable cardiac filling times for each cardiac cycle. Cardiovascular system examination : On auscultation variable intensity of the first heart sound
In atrial fibrillation the irregular atrial activity results in variable cardiac filling times for each cardiac cycle.
Cardiovascular system examination : Hypotension During an acute episode the blood pressure may drop due to lowered cardiac output. Cardiovascular system examination : Hypotension
During an acute episode the blood pressure may drop due to lowered cardiac output.
Respiratory system examination : Fine crepitations Due to pulmonary congestion. This is secondary to ineffective pumping out of blood by the heart due to increased heart rate. Respiratory system examination : Fine crepitations
Due to pulmonary congestion. This is secondary to ineffective pumping out of blood by the heart due to increased heart rate.
Assessment of Airway, Breathing and Circulation Patients who present with cardiac arrest require prompt resuscitation. Inspect the mouth for objects which could cause obstruction - secretions, dentures. Observe for chest movements. Listen and feel for breathing. Pulse rate, blood pressure, capillary refill time will provide an assessment of the circulation. Assessment of Airway, Breathing and Circulation
Patients who present with cardiac arrest require prompt resuscitation. Inspect the mouth for objects which could cause obstruction - secretions, dentures. Observe for chest movements. Listen and feel for breathing. Pulse rate, blood pressure, capillary refill time will provide an assessment of the circulation.
Features of associated cardiac diseases Wolff-parkinson-white syndrome is associated with other cardiac diseases such as cardiomyopathies, Ebstein anomaly, Hypertrophic cardiomyopathy, transposition of the great arteries. etc. Features of associated cardiac diseases
Wolff-parkinson-white syndrome is associated with other cardiac diseases such as cardiomyopathies, Ebstein anomaly, Hypertrophic cardiomyopathy, transposition of the great arteries. etc.

Investigations - Diagnosis

Fact Explanation
Electrocardiography (ECG) The diagnosis of WPW syndrome is made by ECG findings. Holter monitoring may be used to monitor the cardiac electrical activity for 24 hours. Classic ECG changes identified : narrow PR interval, widened QRS complex & Delta wave (slow rise of the upstroke of QRS complex). Electrocardiography (ECG)
The diagnosis of WPW syndrome is made by ECG findings. Holter monitoring may be used to monitor the cardiac electrical activity for 24 hours. Classic ECG changes identified : narrow PR interval, widened QRS complex & Delta wave (slow rise of the upstroke of QRS complex).
Thyroid function test Rule out hyperthyroidism which may cause tachyarrhythmias. Thyroid function test
Rule out hyperthyroidism which may cause tachyarrhythmias.
Full blood count Anemia may lead to rapid heart rate. Full blood count
Anemia may lead to rapid heart rate.
Serum creatinine, blood urea, serum electrolytes. Renal failure can induce a rapid heart rate. Serum creatinine, blood urea, serum electrolytes.
Renal failure can induce a rapid heart rate.

Investigations - Management

Fact Explanation
Echocardiography Echocardiography is used assess left ventricular function. Associated cardiac conditions such as cardiomyopathy, congenital heart diseases can also be excluded. Echocardiography
Echocardiography is used assess left ventricular function. Associated cardiac conditions such as cardiomyopathy, congenital heart diseases can also be excluded.
Electrophysiological studies Uses of Electrophysiological studies : Find the location of the accessory pathway, determine the electrophysiological properties of the abnormal pathway, determine response to drug therapy. Electrophysiological studies
Uses of Electrophysiological studies : Find the location of the accessory pathway, determine the electrophysiological properties of the abnormal pathway, determine response to drug therapy.

Management - Supportive

Fact Explanation
Patient education and counseling The patient should be provided information about the condition, complications, triggering factors and treatment options available. Counsel the patient regarding the risk of sudden cardiac arrest and occupational risks. Patient education and counseling
The patient should be provided information about the condition, complications, triggering factors and treatment options available. Counsel the patient regarding the risk of sudden cardiac arrest and occupational risks.
Management plan should be individualized The most appropriate treatment option should be selected following consideration of the disease presentation, severity of symptoms, risks to patient and patient wishes/ expectations. Treatment options include expectant management, anti-arrhythmic drug therapy, radio-frequency ablation and surgical therapy. Management plan should be individualized
The most appropriate treatment option should be selected following consideration of the disease presentation, severity of symptoms, risks to patient and patient wishes/ expectations. Treatment options include expectant management, anti-arrhythmic drug therapy, radio-frequency ablation and surgical therapy.

Management - Specific

Fact Explanation
Management of acute episodes Patients who present in a collapsed unconscious state require prompt resuscitation. Assess and support the airway, breathing and circulation. If the patient is in cardiac arrest administer advanced life support. Assess the rhythm of heart. Use electrical cardioversion if the arrhythmia is causing haemo-dynamic instability. Medical management depends on the type of tachy-arrhythmia that has developed. Patients experiencing atrial fibrillation/ atrial flutter can be managed with calcium channel blockers - verapamil, diltiazem or beta-blockers - Propranolol or digoxin. For junctional tachycardia (AVRT & AVNRT) vagal manoeuvres followed by adenosine or beta-blocker therapy can be used. Management of acute episodes
Patients who present in a collapsed unconscious state require prompt resuscitation. Assess and support the airway, breathing and circulation. If the patient is in cardiac arrest administer advanced life support. Assess the rhythm of heart. Use electrical cardioversion if the arrhythmia is causing haemo-dynamic instability. Medical management depends on the type of tachy-arrhythmia that has developed. Patients experiencing atrial fibrillation/ atrial flutter can be managed with calcium channel blockers - verapamil, diltiazem or beta-blockers - Propranolol or digoxin. For junctional tachycardia (AVRT & AVNRT) vagal manoeuvres followed by adenosine or beta-blocker therapy can be used.
Treat precipitants of arrhythmia attacks Conditions which may precipitate or worsen dysarrhythmia such as coronary heart disease, valvular heart disease cardiomyopathy, pericarditis, electrical/metabolic disturbances hyperthyroidism, anemia etc should be treated appropriately. Treat precipitants of arrhythmia attacks
Conditions which may precipitate or worsen dysarrhythmia such as coronary heart disease, valvular heart disease cardiomyopathy, pericarditis, electrical/metabolic disturbances hyperthyroidism, anemia etc should be treated appropriately.
Conservative observation Asymptomatic patients diagnosed incidentally by ECG can be observed expectantly. Conservative observation
Asymptomatic patients diagnosed incidentally by ECG can be observed expectantly.
Radiofrequency ablation This is the treatment of choice for many symptomatic patients and patients who experience episodes of arrhythmia. Indications : Symptomatic patients, Patients at high risk of cardiac arrest/sudden cardiac death, asymptomatic patients with occupational, live hood hazards and patients who develop rapid ventricular rates following atrial tachyarrhythmias. Catheters inserted via the femoral vessels are advanced to the heart. The accessory pathway is located and ablated using radiofrequency thermal energy. This procedure can be used in any age group and has a high success rate. Advantages of the procedure are that it is curative and eliminates the need for lifelong medication. Prophylactic radio-frequency ablation is currently being increasingly used in asymptomatic patients with high risk of dysarrhythmia as there is a marked reduction in arrhythmic events. Radiofrequency ablation
This is the treatment of choice for many symptomatic patients and patients who experience episodes of arrhythmia. Indications : Symptomatic patients, Patients at high risk of cardiac arrest/sudden cardiac death, asymptomatic patients with occupational, live hood hazards and patients who develop rapid ventricular rates following atrial tachyarrhythmias. Catheters inserted via the femoral vessels are advanced to the heart. The accessory pathway is located and ablated using radiofrequency thermal energy. This procedure can be used in any age group and has a high success rate. Advantages of the procedure are that it is curative and eliminates the need for lifelong medication. Prophylactic radio-frequency ablation is currently being increasingly used in asymptomatic patients with high risk of dysarrhythmia as there is a marked reduction in arrhythmic events.
Anti-arrhythmic medications Anti-arrhythmic agents can be used to slow the conduction via the accessory pathway and block conduction through the AV node. Agents that can be used are : Class 1c drugs – flecainide, Class 3 drugs – amiodarone, sotalol, Class 4 drugs – verapamil. Dual therapy with class 1a and class 4 agents can be used. Commonly used drugs are propranolol, lidocaine, Procainamide, amiodarone, sotalol. Even though used in practice long term anti-arrhythmic therapy has low success rate in preventing paroxysmal arrhythmic episodes. This mode of therapy is considered for patients contraindicated for radio-frequency ablation. Anti-arrhythmic medications
Anti-arrhythmic agents can be used to slow the conduction via the accessory pathway and block conduction through the AV node. Agents that can be used are : Class 1c drugs – flecainide, Class 3 drugs – amiodarone, sotalol, Class 4 drugs – verapamil. Dual therapy with class 1a and class 4 agents can be used. Commonly used drugs are propranolol, lidocaine, Procainamide, amiodarone, sotalol. Even though used in practice long term anti-arrhythmic therapy has low success rate in preventing paroxysmal arrhythmic episodes. This mode of therapy is considered for patients contraindicated for radio-frequency ablation.
Open heart surgery Use of open heart surgery has diminished with the use of radio-frequency ablation. This may be considered if repeated attempts of radio-frequency ablation fail to improve the patient’s condition. Newer modified close heart surgeries which are simple and less invasive are being experimented with. Open heart surgery
Use of open heart surgery has diminished with the use of radio-frequency ablation. This may be considered if repeated attempts of radio-frequency ablation fail to improve the patient’s condition. Newer modified close heart surgeries which are simple and less invasive are being experimented with.
Management of pregnant patients During the antenatal period manage the patient with anti-arrhythmic drugs such as sotalol and flecainide. Radio-frequency ablation may be considered after pregnancy. Management of pregnant patients
During the antenatal period manage the patient with anti-arrhythmic drugs such as sotalol and flecainide. Radio-frequency ablation may be considered after pregnancy.

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  1. AL-KHATIB SM, PRITCHETT EL. Clinical features of Wolff-Parkinson-White syndrome. Am Heart J [online] 1999 Sep, 138(3 Pt 1):403-13 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/10467188
  2. BECKMAN KAREN J., GALLASTEGUI JOSE L., BAUMAN JERRY L., HARIMAN ROBERT J.. The predictive value of electrophysiologic studies in untreated patients with Wolff-Parkinson-White syndrome. Journal of the American College of Cardiology [online] 1990 March, 15(3):640-647 [viewed 15 July 2014] Available from: doi:10.1016/0735-1097(90)90639-7
  3. BERRY VA. Wolff-Parkinson-White syndrome and the use of radiofrequency catheter ablation. Heart Lung [online] 1993 Jan-Feb, 22(1):15-25 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/8420852
  4. BLOMSTROMLUNDQVIST C. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias—executive summary A Report of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines(Writing Committee to Develop Guidelines for the Management of Patients With Supraventricular Arrhythmias)Developed in collaboration with NASPE–Heart Rhythm Society. European Heart Journal [online] 2003 October, 24(20):1857-1897 [viewed 15 July 2014] Available from: doi:10.1016/j.ehj.2003.08.002
  5. CALKINS H. Catheter ablation of accessory pathways is associated with an excellent long-term prognosis. European Heart Journal [online] 2001 April, 22(7):532-533 [viewed 15 July 2014] Available from: doi:10.1053/euhj.2000.2523
  6. CHANDRA MS, KERBER RE, BROWN DD, FUNK DC. Echocardiography in Wolff-Parkinson-White syndrome. Circulation [online] 1976 Jun, 53(6):943-6 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/131657
  7. CHUNG EK. Wolff-Parkinson-White Syndrome--current views. Am J Med [online] 1977 Feb, 62(2):252-66 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/299982
  8. DEWAR RI, LIP GY. Identification, diagnosis and assessment of atrial fibrillation Heart [online] 2007 Jan, 93(1):25-28 [viewed 15 July 2014] Available from: doi:10.1136/hrt.2006.099861
  9. GUIRAUDON GM, KLEIN GJ, GULAMHUSEIN S, JONES DL, YEE R, PERKINS DG, JARVIS E. Surgical repair of Wolff-Parkinson-White syndrome: a new closed-heart technique. Ann Thorac Surg [online] 1984 Jan, 37(1):67-71 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/6691739
  10. KULIG J., KOPLAN B. A.. Wolff-Parkinson-White Syndrome and Accessory Pathways. Circulation [online] December, 122(15):e480-e483 [viewed 15 July 2014] Available from: doi:10.1161/CIRCULATIONAHA.109.929372
  11. MARK DG, BRADY WJ, PINES JM. Preexcitation syndromes: diagnostic consideration in the ED. Am J Emerg Med [online] 2009 Sep, 27(7):878-88 [viewed 15 July 2014] Available from: doi:10.1016/j.ajem.2008.06.013
  12. PAPPONE C, SANTINELLI V, MANGUSO F, AUGELLO G, SANTINELLI O, VICEDOMINI G, GULLETTA S, MAZZONE P, TORTORIELLO V, PAPPONE A, DICANDIA C, ROSANIO S. A randomized study of prophylactic catheter ablation in asymptomatic patients with the Wolff-Parkinson-White syndrome. N Engl J Med [online] 2003 Nov 6, 349(19):1803-11 [viewed 15 July 2014] Available from: doi:10.1056/NEJMoa035345
  13. ROSNER MH, BRADY WJ JR, KEFER MP, MARTIN ML. Electrocardiography in the patient with the Wolff-Parkinson-White syndrome: diagnostic and initial therapeutic issues. Am J Emerg Med [online] 1999 Nov, 17(7):705-14 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/10597097
  14. SETHI KK, DHALL A, CHADHA DS, GARG S, MALANI SK, MATHEW OP. WPW and preexcitation syndromes. J Assoc Physicians India [online] 2007 Apr:10-5 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18368860
  15. TAN H. Treatment of tachyarrhythmias during pregnancy and lactation. European Heart Journal [online] 2001 March, 22(6):458-464 [viewed 15 July 2014] Available from: doi:10.1053/euhj.2000.2130
  16. WELLENS H. J. J.. Catheter Ablation of Cardiac Arrhythmias : Usually Cure, but Complications May Occur. Circulation [online] 1999 January, 99(2):195-197 [viewed 15 July 2014] Available from: doi:10.1161/01.CIR.99.2.195
  17. WELLENS HJ, LIE KI, BäR FW, WESDORP JC, DOHMEN HJ, DüREN DR, DURRER D. Effect of amiodarone in the Wolff-Parkinson-White syndrome. Am J Cardiol [online] 1976 Aug, 38(2):189-94 [viewed 15 July 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/952262
  18. WOLFF L, PARKINSON J, WHITE, PD. Bundle-branch block with short P-R interval in healthy young people prone to paroxysmal tachycardia. American Heart Journal, 1930, 5, 685-704.