What is the Difference Between Polymorphic and Monomorphic Ventricular Tachycardia?

Polymorphic ventricular tachycardia (VT) and monomorphic ventricular tachycardia (VT) are both types of ventricular tachycardia, which is a fast heart rhythm originating from the ventricles. The key difference between the two lies in the QRS morphology on an electrocardiogram (ECG):

Polymorphic VT: Characterized by a constantly changing QRS complex, with beat-to-beat variation in QRS shape and multiple QRS morphologies. The electrical activity in the heart is more unstable in polymorphic VT.
Monomorphic VT: Characterized by a single, stable QRS morphology with no beat-to-beat variation. The QRS complexes are consistent in shape and appear uniform and symmetrical.

Polymorphic VT is often associated with unstable electrical activity in the heart and is considered more dangerous than monomorphic VT. Monomorphic VT, on the other hand, is usually caused by a myocardial scar and is more common in patients with structural heart disease or certain medications and electrolyte imbalances. Treatment options for both types of ventricular tachycardia may include medications, catheter ablation of the heart, or other therapeutic interventions.

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What is the Difference Between Polymorphic and Monomorphic Ventricular Tachycardia?

Comparative Table: Polymorphic vs Monomorphic Ventricular Tachycardia

Here is a table comparing the differences between Polymorphic Ventricular Tachycardia (PVT) and Monomorphic Ventricular Tachycardia (MVT):

Feature	Polymorphic Ventricular Tachycardia (PVT)	Monomorphic Ventricular Tachycardia (MVT)
QRS Complex	Constantly changing QRS complex	Consistent QRS complex
Origin	Ventricular tachycardia originates in different places around the ventricle	Ventricular tachycardia repeatedly originates in the same place of the ventricle
Association	Structural heart disease, certain medications, electrolyte imbalances	Structural heart disease, certain medications, electrolyte imbalances
QT Interval	More likely to have prolonged QT interval	Less likely to have prolonged QT interval
Treatment	Intravenous magnesium, removing offending drugs, or correcting potassium and calcium imbalances	Treatment generally better than PVT

PVT and MVT are both types of ventricular tachycardia, which are fast heart rhythms originating from the ventricles. The main difference between the two is that PVT is characterized by a constantly changing QRS complex, while MVT has a consistent QRS complex.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.