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[Hemodynamic aspects of torsade de pointes: echocardiographic study of a case]
Insights
Torsade de Point (T.D.P.) causes reduced stroke volume due to mechanical failure from partial ventricular desynchronization. Echocardiogram showed inconsistent aortic valve opening during T.D.P. compared to ventricular pacing.
Area of Science:
- Cardiology
- Cardiac Electrophysiology
- Echocardiography
Background:
- Torsade de Point (T.D.P.) is a specific ventricular tachyarrhythmia often associated with complete heart block.
- Understanding the mechanical consequences of T.D.P. is crucial for patient management.
Observation:
- M-mode echocardiography was performed during a T.D.P. episode in a patient with complete heart block.
- The study observed inconsistent, incomplete, and unequal aortic valve opening during the T.D.P. attack.
- In contrast, ventricular pacing at a similar rate resulted in constant and complete aortic valve opening.
Findings:
- The reduction in stroke volume during T.D.P. is primarily attributed to mechanical failure.
- This mechanical failure stems from partial desynchronization of ventricular activation.
- The observed desynchronization is less complete than that seen in ventricular fibrillation.
Implications:
- These findings highlight the mechanical impact of ventricular arrhythmias on cardiac output.
- Echocardiography can reveal distinct patterns of aortic valve function during T.D.P. versus paced rhythms.
- Understanding T.D.P.'s mechanical basis may inform therapeutic strategies for arrhythmias affecting cardiac function.
Abstract:
In a patient with complete heart block complicated by "Torsade de point" (T.D.P.) we were able to record an M-mode echocardiogram during an attack of this peculiar ventricular tachyarrhythmia. The aortic valve opening was inconstant, incomplete and unequal during the T.D.P. (13 sec.), although the rate of the tachyarrhythmia was almost constant. On the other hand, during a subsequent ventricular pacing at a comparable rate like, the aortic valve opening was constant and complete. On the basis of these observations we conclude that the reduction of stroke volume, observed in T.D.P., is mainly due to mechanical failure as a result of partial desynchronization of the ventricular activation, as in ventricular fibrillation in which, however, the desynchronization is complete.