Indications for pacemakers, implantable cardioverter-defibrillator and cardiac resynchronization devices.

Implantable cardiac devices are important management tools for patients with heart rhythm disorders and heart failure. In this article, the current implantable cardiac rhythm devices are described in their evolution. The current indications and contraindications for these cardiac rhythm devices are reviewed.

Clinical significance of increased tricuspid valve incompetence following implantation of ventricular leads.

Purpose: Cardiac rhythm management devices (CRMD) require a ventricular lead to be placed across the tricuspid valve. Tricuspid regurgitation (TR) is an under-recognized clinical complication of lead implantation and its clinical significance is unknown. We studied the incidence of hospitalizations for congestive heart failure (CHF) exacerbation among patients with worsening TR after ventricular lead implantation.

Dofetilide reduces the frequency of ventricular arrhythmias and implantable cardioverter defibrillator therapies.

Background: Patients with an implanted cardioverter defibrillator (ICD) and ventricular arrhythmias leading to ICD therapies have poor clinical outcomes and quality of life. Antiarrhythmic agents and catheter ablation are needed to control these arrhythmias. Dofetilide has only been approved for the treatment of atrial fibrillation.

Cardiac resynchronization therapy: evaluation of ventricular dysynchrony and patient selection.

Cardiac resynchronization therapy (CRT) is an established treatment modality for systolic heart failure. Aimed to produce simultaneous biventricular stimulation and correct the lack of ventricular synchrony in selected patients with congestive heart failure, CRT has shown to improve mortality and reduce hospital admissions when compared to medical treatment. At present, the indication criteria for the implantation of a CRT device include an ejection fraction of less than 35%, heart failure symptoms consistent with NYHA functional class III-IV and a QRS complex duration equal or longer than 120 milliseconds.

Distal balloon occlusion allows epicardial lead placement in a tortuous branch of the great cardiac vein.

Cardiac resynchronization therapy (CRT) is a well established treatment modality in heart failure. Using standard techniques, placement of the left ventricular (LV) lead is usually successful; however LV lead placement failure remains a clinical problem. In the present report, the standard over-the-wire technique was not successful due to absence of the necessary support to place the lead into a tortuous vein.

Efficacy and safety of dofetilide in patients with atrial fibrillation and atrial flutter.

Background: Dofetilide, an I(Kr) blocker has been demonstrated to be effective in terminating persistent atrial fibrillation and flutter (AF/AFL), and in maintaining sinus rhythm after direct current cardioversion (CV). It is not known, however, whether pharmacological conversion with dofetilide predicts maintenance of sinus rhythm. In addition, there is limited information comparing the efficacy of dofetilide in persistent versus paroxysmal AF/AFL.

Selection of drugs in pursuit of rate control strategy.

Atrial fibrillation is the most common sustained arrhythmia. Based on multiple large randomized trials, rate control therapy has been shown to be safe and effective and is gaining greater acceptance as a frontline alternative to drugs to maintain sinus rhythm. Adequate rate control can be achieved by atrioventricular nodal blocking agents both in the acute and chronic settings.

Ablation of tachyarrhythmias in pediatric patients.

Purpose Of Review: Radiofrequency (RF) ablation treatment for tachyarrhythmias has been available only for the past 15 years. The success rates have been excellent with a very low frequency of complications. Because of this efficacy, the use of RF ablation in children has become standard of care even though long-term data are unavailable.