Managed ventricular pacing

Sweeney MO, Ellenbogen KA, Casavant D, Betzold R, Sheldon T, Tang F, Mueller M, Lingle J. Multicenter, prospective, randomized safety and efficacy study of a new atrial-based managed ventricular pacing mode (MVP) in dual chamber ICDs. J Cardiovasc Electrophysiol 2005 16 811-7. 

Halinen MO. Mexiletine for the management of ventricular arrhythmias in ischemic heart disease. Clin Progr Electrophysiol Pacing 1986 4 580-1. 

Sami MH. Mexiletine its role in the management of chronic ventricular arrhythmias. Clin Progr Electrophysiol Pacing 1986 4 582-8. 

A woman with congenital heart disease and atrial and ventricular arrhythmias managed by an implanted cardioverter defibrillator, epicardial pacing and amiodarone 400 mg daily, experienced deterioration in the control of her condition. She developed palpitations and experienced a shock from the defibrillator. Her amiodarone serum levels were 40% lower than 2 months previously, and her A-desethylamiodarone levels were undetectable. It was noted that 5 weeks earlier rifampicin 600 mg daily had been started to treat an infection of the pacing system. The amiodarone dose was doubled, but the palpitations continued. Amiodarone and A-desethy-lamiodarone levels increased after rifampicin was discontinued. Rifampicin is a potent enzyme inducer and it may have increased the metabolism and clearance of amiodarone. This case suggests that combined use of amiodarone and rifampicin should be well monitored. 

Bristow, M.R., A.M. Feldman, and L.A. Saxon, Heart failure management using implantable devices for ventricular resynchronization Comparison of Medical Therapy, Pacing, and Defihrillation in Chronic Heart Failure (COMPANION) trial. COMPANION Steering Committee and COMPANION Clinical Investigators. J Card Fail, 2000. 6(3) p. 276-85. 

Although it has not been extensively studied at present, some patients with chronic AF may receive CRT ICD devices. In these patients the mode is preferably VVIR. Again, since the goal is to pace the ventricles 100% of the time, native conduction to the ventricles in AF needs to be prevented. This is accomplished by providing an adequate lower and upper rate, and utilizing adjunctive AV nodal blocking medicines when needed. In more extreme circumstances the AV node may need to be ablated when medical management cannot control a rapid ventricular response in AF. 

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