Monomorphic sustained ventricular tachycardia

A monomorphic sustained ventricular tachycardia does not occur frequently in ACS, especially in patients without prior infarctions. However, it has been shown to have worse prognosis in 1-year follow-up period than that of patients with primary VF (Newby et al., 1998). It is partly related to prior infarction scar, which explains its lower incidence following a first myocardial infarction (Fiol, 2001 Mont et al., 1996). Rarely, it may appear during the course of a significant and sustained coronary spasm. 

Pinar Bermudez E, Garcia-Alberola A, Martinez Sanchez J, Sanchez Munoz JJ, Valdes Chavarri M. Spontaneous sustained monomorphic ventricular tachycardia after administration of ajmaline in a patient with Brugada syndrome. Pacing Clin Electrophysiol 2000 23(3) 407-9. 

A 71-year-old Japanese man with bouts of sustained monomorphic ventricular tachycardia, in whom non-sustained polymorphic ventricular tachycardia was induced by rapid pacing during electrophysiological studies, was given amiodarone and developed three different types of sustained monomorphic ventricular... 

Symptomatic bradycardia, junctional rhythm, non-sustained and/or monomorphic ventricular tachycardia... 

In patients with sustained monomorphic ventricular tachycardia inducible by programmed electrical stimulation, who had previously been unsuccessfully treated with... 

Bashir Y, Thomsen PE, Kingma JH, Moller M, Wong C, Cobbe SM, Jordaens L, Campbell RW, Rasmussen HS, Camm AJ. Electrophysiologic profile and efficacy of intravenous dofetilide (UK-68,798), a new class III antiarrhythmic drug, in patients with sustained monomorphic ventricular tachycardia. Dofetilide Arrhythmia Study Group. Am J Cardiol 1995 76(14) 1040-4. 

Mont L, Cinca J, Blanch P et al. Predisposing factors and prognostic value of sustained monomorphic ventricular tachycardia in the early phase of acute myocardial infarction. J Am Coll Cardiol 1996 28 1670. 

Gorgels A, van den Dool A, Hofs A, et al. Comparison of procainamide and lidocaine in terminating sustained monomorphic ventricular tachycardia. Am J Cardiol 1996 78 43-46. 

The introduction and manipulation of pacing leads are frequently associated with both tachyarrhythmias and bradyarrhythmias as a lead negotiates the chambers of the right heart. Ventricular tachycardia is extremely common as the pacing electrode or guidewire contacts the right ventricular myocardium. Simple withdrawal of these objects usually terminates the arrhythmia. In extreme cases, sustained monomorphic ventricular tachycardia and even ventricular fibrillation may occur. Some institutions have instituted a policy of placing external defibrillation pads prophylactically in anticipation of required cardioversion. 

MADIT was the first randomized trial to show that the ICD, used as a prophylactic, can reduce the risk of death in high-risk patients. The MADIT assessed patients who had coronary artery disease and a prior Q-wave myocardial infarction. To be included, patients had to have (a) asymptomatic nonsustained ventricular tachycardia recorded on a 24-h Hotter monitor, (b) a left ventricular ejection fraction of < 0.35 and, (c) inducible sustained monomorphic ventricular tachycardia or ventricular fibrillation not suppressed by procainamide at electrophysiology testing. 

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