Tachycardia: Difference between revisions
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* Cardiogenic shock | * Cardiogenic shock | ||
Additional information about drug is mandatory. Toxic levels of digoxin and cocain can lead to VT's. | Additional information about drug use is mandatory. Toxic levels of digoxin and cocain can lead to VT's. Also additional information about family history of sudden cardiac death is helpfull, as it is a strong predictor of susceptibility to ventricular arrhythmias and sudden cardiac death. | ||
===Physical Examination=== | ===Physical Examination=== | ||
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* Variable splitting of the first and second heart sounds, and intermittent presence of a third and/or fourth heart sound. | * Variable splitting of the first and second heart sounds, and intermittent presence of a third and/or fourth heart sound. | ||
===Diagnostic Evaluation=== | |||
'''Exercise testing''' | |||
: Exercise testing is recommended in adult patients with ventricular tachycardias who have an intermediate or greater probability of having coronary heart disease by age, gender and symptoms. It is meant to provoke ischemic changes or ventricular arrhythmias. | |||
'''Ambulatory (Holter) ECG''' | |||
: Ambulatory ECG is necessary if the diagnosis needs to be clarified, by detecting arrhythmias, QT-interval changes, T-wave alternans (TWA) or ST-segment changes. | |||
'''Echocardiography, Cardiac CT, MRI''' | |||
: Echocardiography is recommended in patients with ventricular tachycardias who are suspected of having a structural heart disease. If echocardiography does not provide accurate assessment of the left and right ventricular function and/or structural changes, cardiac CT or MRI can be done. | |||
'''Exercise testing with an image modality (echocardiography or nuclear perfusion)''' | |||
: Some patients with ventricular arrhythmias have an intermediate probability of coronairy heart disease, but their ECG is less reliabe (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 coronairy heart disease in patients with ventricular arrhythmias who have an intermediate or greater probability of having coronairy 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 coronairy heart disease. | |||
==Ventricular tachycardia== | ==Ventricular tachycardia== | ||
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===Differential diagnosis=== | ===Differential diagnosis=== | ||
(Non)sustained | (Non)sustained VT may be idiopathic, but occurs most frequently in patients with underlying structural heart disease of various types including: | ||
* Coronary heart disease (CHD) with prior myocardial infarction (is the most frequent cause in developed countries) | * Coronary heart disease (CHD) with prior myocardial infarction (is the most frequent cause in developed countries) | ||
* Hypertrophic cardiomyopathy | * Hypertrophic cardiomyopathy | ||