Ventricular Tachycardia in Young Women
Primary Etiologies
- In a 30-year-old white female, VT most commonly occurs in the absence of structural heart disease and is often related to elevated catecholamines, though congenital long QT syndrome, pregnancy-related cardiomyopathy, and idiopathic VT are critical considerations 1, 2
- Catecholamine-mediated VT occurs frequently in young women without overt structural disease and is typically beta-blocker sensitive 1, 2
- Women have significantly higher risk of long QT-related VT and torsades de pointes compared to men, with 70% of Long QT Registry subjects being female 3, 1, 2
Congenital and Structural Heart Disease
- Post-pubertal females experience predominant incidence of cardiac arrests and syncope from long QT syndrome, whereas males are at higher risk before puberty 3, 1, 2
- Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death in young people, including young adults, with complex ventricular arrhythmias occurring in 90% of adults with HCM 5
- Dilated cardiomyopathy can present with ventricular arrhythmias 3
Metabolic and Endocrine Causes
- Thyroid disorders: Hypothyroidism causes QT prolongation and VT risk, while thyrotoxicosis rarely causes VT except with electrolyte disturbances 6
- Pheochromocytoma may present with VT due to catecholamine excess and can cause reversible cardiomyopathy 6
- Electrolyte imbalances from primary aldosteronism, Addison disease, or parathyroid disorders cause arrhythmogenesis through QRS and QTc prolongation 6
- Diabetes is a more pronounced predictor of coronary disease and VT in women compared to men 3, 1, 2
Diagnostic Considerations
- The American College of Cardiology recommends obtaining a 12-lead ECG during sinus rhythm to identify QT prolongation, pre-excitation, or structural abnormalities, although this specific recommendation is from the Journal of the American College of Cardiology 5
- Echocardiography is recommended to evaluate for structural heart disease, including HCM, cardiomyopathy, and valvular disease 5
- Laboratory evaluation including electrolytes, thyroid function, and consideration of catecholamine levels if pheochromocytoma suspected is necessary 6
- Family history of sudden cardiac death or long QT syndrome should be considered 5