Tachycardia: Difference between revisions

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==Ventricular tachycardia==
==Ventricular tachycardia==
[[Image:Vent1.jpg|thumb|right|400px]]
[[Image:SR_VT.svg|thumb|right|400px]]


Ventricular tachycardias (VT's) are rhythm disturbances that arise in the ventricles.  
Ventricular tachycardias (VT's) are rhythm disturbances that arise in the ventricles.  
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*'''Exercise testing with an image modality (echocardiography or nuclear perfusion):''' Some patients with ventricular arrhythmias have an intermediate probability of coronary heart disease, but their ECG is less reliable (because of digoxin use, LVH, greater than 1mm ST-segment depression at rest, WPW syndrome or LBBB). For detecting silent ischemia in these patients exercise testing with an image modality can be done. If patients are unable to perform exercise, a pharmacological stress test with an imaging modality can be done.  
*'''Exercise testing with an image modality (echocardiography or nuclear perfusion):''' Some patients with ventricular arrhythmias have an intermediate probability of coronary heart disease, but their ECG is less reliable (because of digoxin use, LVH, greater than 1mm ST-segment depression at rest, WPW syndrome or LBBB). For detecting silent ischemia in these patients exercise testing with an image modality can be done. If patients are unable to perform exercise, a pharmacological stress test with an imaging modality can be done.  
*'''Coronary angiography:''' Coronary angiography can diagnose or exclude the presence of significant obstructive coronary heart disease in patients with ventricular arrhythmias who have an intermediate or greater probability of having coronary heart disease.  
*'''Coronary angiography:''' Coronary angiography can diagnose or exclude the presence of significant obstructive coronary heart disease in patients with ventricular arrhythmias who have an intermediate or greater probability of having coronary heart disease.  
*'''Electrophysiological testing:''' Electrophysiological testing can be performed to guide and assess the efficacy of VT ablation in patients with ventricular arrhythmias. It can also be done to clarify the mechanism of broad complex tachycardias in patients with coronary heart disease.  
*'''Electrophysiological testing:''' Electrophysiological testing can be performed to guide and assess the efficacy of VT ablation in patients with ventricular arrhythmias. It can also be done to clarify the mechanism of broad complex tachycardias in patients with coronary heart disease.


==Overview of ventricular tachycardias==
==Overview of ventricular tachycardias==