Difference between revisions of "Bundle Branch Block"

From WikiVet English
Jump to navigation Jump to search
(Created page with '*Abnormal ventricular excitation as the result of blockage to the right bundle branch, the left bundle branch, or left anterior fascicular block. ====Right Bundle Branch Block=…')
 
 
(3 intermediate revisions by 2 users not shown)
Line 1: Line 1:
*Abnormal ventricular excitation as the result of blockage to the right bundle branch, the left bundle branch, or left anterior fascicular block.
+
{{OpenPagesTop}}
 +
== Introduction ==
  
 +
This condition is an '''abnormal ventricular excitation''' as the result of blockage to the right bundle branch, the left bundle branch, or left anterior fascicular block.
  
====Right Bundle Branch Block====
+
'''Right bundle branch block''' is characterised by the failure or delay of conduction through the right bundle branch. The left ventricle is unaffected. Some causes of this condition include pulmonary [[embolism]], [[Dirofilaria immitis|heart worm]], [[:Category:Electrolytes|electrolyte]] disturbances, congenital diseases etc.
Characterised by the failure or delay of conduction through the right bundle branch. Left ventricle is unaffected.
 
  
 +
In '''left bundle branch block''', there is failure of conduction through the left bundle branch and the right ventricle is unaffected. Causes of this include congenital abnormalities and [[:Category:Myocardial Pathology|myocardial diseases]].
  
=====Causes=====
+
There can also be a '''left anterior fasicular block''', which is characterised by the failure of conduction through the anterior fascicle of the left bundle branch. Causes of this include electrolyte abnormalities and [[:Category:Cardiomyopathy|cardiomyopathies]] e.g. in the cat.
Pulmonary embolism, heart worm, electrolyte disturbances, congenital diseases etc.
 
  
  
'''ECG Appearance:''' Wide QRS complex, Wide S wave
+
== Signalment ==
  
 +
The disease is described in both cats and dogs.
  
=====Treatment=====
 
Treat the underlying cause
 
  
 +
== Clinical Signs ==
  
====Left Bundle Branch Block====
+
Many cases of bundle branch block are asymptomatic and are only detected on ECG. However, more severe cases will cause ventricular muscle damage and therefore signs of heart disease will occur. Some animals may present due to syncope, weakness or exercise intolerance.
Characterised by the failure of conduction through the left bundle branch. Right ventricle is unaffected.
 
  
  
=====Causes=====
+
== Diagnosis ==
Congenital abnormalities, myocardial diseases etc.
 
  
=====Treatment=====
+
An '''Electrocardiograph''' (ECG) is the diagnostic method of choice.
Treat the underlying cause
+
:In a right bundle branch block, one may see a '''wide QRS complex and a wide S wave'''.
 +
:In left anterior fasicular block there will be a '''normal QRS wave, a tall R waves and deep S waves'''.
  
  
'''Left Anterior Fascicular Block'''=characterised by the failure of conduction through the anterior fascicle of the left bundle branch.
+
== Treatment ==
  
 +
Unless the condition is congenital, treatment is by treating the underlying cause.
  
'''Causes:''' Electrolyte abnormalities, hypertrophic cardiomyopathy (cat), etc.
 
  
 +
== References ==
  
'''ECG Appearance:''' Normal QRS, tall R waves, deep S waves
+
Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition), W.B. Saunders Company
  
 +
Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2), W.B. Saunders Company
  
'''Treatment:''' Treat the underlying cause[[Category:Impulse_Conduction_Abnormalities]][[Category:To_Do_-_Cardiovascular]]
+
Fossum, T. W. et. al. (2007) Small Animal Surgery (Third Edition), Mosby Elsevier
 +
 
 +
Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial
 +
 
 +
Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition), Mosby Elsevier.
 +
 
 +
 
 +
{{review}}
 +
 
 +
{{OpenPages}}
 +
 
 +
[[Category:Impulse_Conduction_Abnormalities]] [[Category:Expert_Review]]
 +
[[Category:Cardiology Section]]

Latest revision as of 14:40, 15 October 2013


Introduction

This condition is an abnormal ventricular excitation as the result of blockage to the right bundle branch, the left bundle branch, or left anterior fascicular block.

Right bundle branch block is characterised by the failure or delay of conduction through the right bundle branch. The left ventricle is unaffected. Some causes of this condition include pulmonary embolism, heart worm, electrolyte disturbances, congenital diseases etc.

In left bundle branch block, there is failure of conduction through the left bundle branch and the right ventricle is unaffected. Causes of this include congenital abnormalities and myocardial diseases.

There can also be a left anterior fasicular block, which is characterised by the failure of conduction through the anterior fascicle of the left bundle branch. Causes of this include electrolyte abnormalities and cardiomyopathies e.g. in the cat.


Signalment

The disease is described in both cats and dogs.


Clinical Signs

Many cases of bundle branch block are asymptomatic and are only detected on ECG. However, more severe cases will cause ventricular muscle damage and therefore signs of heart disease will occur. Some animals may present due to syncope, weakness or exercise intolerance.


Diagnosis

An Electrocardiograph (ECG) is the diagnostic method of choice.

In a right bundle branch block, one may see a wide QRS complex and a wide S wave.
In left anterior fasicular block there will be a normal QRS wave, a tall R waves and deep S waves.


Treatment

Unless the condition is congenital, treatment is by treating the underlying cause.


References

Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition), W.B. Saunders Company

Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2), W.B. Saunders Company

Fossum, T. W. et. al. (2007) Small Animal Surgery (Third Edition), Mosby Elsevier

Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial

Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition), Mosby Elsevier.




Error in widget FBRecommend: unable to write file /var/www/wikivet.net/extensions/Widgets/compiled_templates/wrt665c96974d30b7_94546589
Error in widget google+: unable to write file /var/www/wikivet.net/extensions/Widgets/compiled_templates/wrt665c9697510370_94519419
Error in widget TwitterTweet: unable to write file /var/www/wikivet.net/extensions/Widgets/compiled_templates/wrt665c9697546b61_87085507
WikiVet® Introduction - Help WikiVet - Report a Problem