Resolution of giant cell myocarditis after extended ventricular assistance.

Lower recurrence rates and improved long-term outcomes are the goal of treatment for giant cell myocarditis (GCM). We describe a case of GCM in an Asian woman who presented with new onset palpitations and syncope. She initially had normal systolic function by echocardiography with magnetic resonance imaging evidence of infiltrative cardiomyopathy.

Radiofrequency catheter ablation of atriofascicular and nodoventricular Mahaim tracts.

Background: Several mechanisms have been proposed to explain the pathogenesis of tachycardia in patients with Mahaim tracts. The tachycardia may involve antegrade conduction over an atriofascicular pathway with decremental properties or a nodofascicular pathway.

Methods And Results: We report six patients with recurrent episodes of preexcited tachycardia with findings consistent with "Mahaim tract" conduction.

Curative percutaneous catheter ablation using radiofrequency energy for accessory pathways in all locations: results in 100 consecutive patients.

Patients with accessory pathway-mediated supraventricular tachycardia have typically been treated with drugs or surgery. Although catheter ablation using high voltage direct current shocks has been used to treat patients with drug-refractory supraventricular tachycardia, there are associated disadvantages, including damage due to barotrauma as well as the need for general anesthesia. Recently, transcatheter radiofrequency energy has evolved as an alternative to direct current shock or surgery to ablate accessory pathways.

Catheter modification of the atrioventricular junction with radiofrequency energy for control of atrioventricular nodal reentry tachycardia.

Background: The utility of transcatheter application of radiofrequency energy to eliminate atrioventricular nodal reentrant tachycardia (AVNRT) was investigated.

Methods And Results: Thirty-nine patients (mean age, 53 +/- 20 years; range 14-86 years) with medically refractory AVNRT underwent perinodal ablation with radiofrequency energy. A custom-designed 6F catheter with a large (3-mm-long) distal electrode and interelectrode pacing of 2 mm was used in the majority of cases.

Ablation of the atrioventricular junction with radiofrequency energy using a new electrode catheter.

Percutaneous catheter ablation using radiofrequency energy can be used to interrupt atrioventricular (AV) conduction in patients with supraventricular tachycardia refractory to drugs. Results of radiofrequency ablation of the AV junction using a custom-designed catheter with a large, 3-mm-long distal electrode, 2-mm interelectrode spacing, and a shaft with increased torsional rigidity were compared with those using a standard quadripolar electrode catheter (Bard EP). An electrocoagulator (Microvasive Bicap 4005) supplied unmodulated radiofrequency current at 550 kHz, which was applied between the distal electrode of the ablation catheter and a large skin electrode.