Category:Impulse Conduction Abnormalities
Atrial Standstill
- Temporary or permanent lack of atrial activity resulting from a failure of atrial depolarisation. Ventricles still function normally.
Causes
Electrolyte abnormalities, cardiomyopathies, muscular dystrophy, hypoadrenocorticism
ECG Appearance: Absence of P waves
Treatment
Treat the underlying cause
Bundle Branch Block
- 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
Characterised by the failure or delay of conduction through the right bundle branch. Left ventricle is unaffected.
Causes
Pulmonary embolism, heart worm, electrolyte disturbances, congenital diseases etc.
ECG Appearance: Wide QRS complex, Wide S wave
Treatment
Treat the underlying cause
Left Bundle Branch Block
Characterised by the failure of conduction through the left bundle branch. Right ventricle is unaffected.
Causes
Congenital abnormalities, myocardial diseases etc.
Treatment
Treat the underlying cause
Left Anterior Fascicular Block=characterised by the failure of conduction through the anterior fascicle of the left bundle branch.
Causes: Electrolyte abnormalities, hypertrophic cardiomyopathy (cat), etc.
ECG Appearance: Normal QRS, tall R waves, deep S waves
Treatment: Treat the underlying cause
Wolff-Parkinson-White Syndrome (Ventricular Preexcitation Syndrome
- This syndrome occurs when the conduction travels from the SA node and then completely bypasses the AV
node and travels to the bundle of His or the ventricles.
Causes
Hypertrophic cardiomyopathy (cats); congenital heart disorders
ECG Appearance: Short PR interval; Prolonged QRS complex; Notch in the R wave
Treatment
Treatment for tachycardia if necessary: digoxin, quinidine etc.
Sick Sinus Syndrome
- This is a blanket term used to describe multiple abnormalities of the SA node involving impulse formation and conduction disturbances.
Causes
Myocardial diseases, idiopathic, breed predispositions (e.g. miniature schnauzer)
ECG: Variable depending on the specific SA abnormality
Treatment
Surgical implantation of a pacemaker; +/- antiarrhythmic treatments
Pages in category "Impulse Conduction Abnormalities"
The following 6 pages are in this category, out of 6 total.