Quarterly vs. yearly clinical follow-up of remotely monitored recipients of prophylactic implantable cardioverter-defibrillators: results of the REFORM trial.

Aims: The rapidly increasing number of patients with implantable cardioverter-defibrillators (ICD) places a large burden on follow-up providers. This study investigated the possibility of longer in-office follow-up intervals in primary prevention ICD patients under remote monitoring with automatic daily data transmissions from the implant memory.

Methods And Results: Conducted in 155 ICD recipients with MADIT II indications, the study compared the burden of scheduled and unscheduled ICD follow-up visits, quality of life (SF-36), and clinical outcomes in patients randomized to either 3- or 12-month follow-up intervals in the period between 3 and 27 months after implantation.

Catheter ablation of electrical storm in patients with structural heart disease.

Aims: Electrical storm (ES) adversely affects prognosis of patients and may become a life-threatening event. Catheter ablation (CA) has been proposed for the treatment of ES. Our goal was to evaluate the efficacy of CA ablation both in acute and long-term suppression of ES.

The relationship between right ventricular pacing voltage and QRS complex duration.

Compared to the natural electrical activation of the myocardium through the His-Purkinje system, right ventricular pacing is associated with prolonged QRS complex duration, thereby impeding the synchronicity of contractions. In left ventricular pacing, a higher pacing voltage decreases the QRS complex duration. The aim of our study was to describe the relation between the right ventricular pacing voltage and the QRS complex duration.

Decrease in plasma B-type natriuretic peptide early after initiation of cardiac resynchronization therapy predicts clinical improvement at 12 months.

Background: Decrease in neurohormonal activation during pharmacotherapy for chronic heart failure (CHF) is associated with haemodynamic and clinical improvement. We tested the hypothesis that changes in neurohormonal activation after initiation of cardiac resynchronization therapy (CRT) predict its long-term clinical effect.

Methods: The study group included 43 patients with CHF (37 males, mean age 62+/-9 years, NYHA class 3.

Optimization of right ventricular lead position in cardiac resynchronisation therapy.

Background: The benefit of biventricular pacing (BiV) may be substantially affected by optimal lead placement.

Aim: To evaluate the importance of right ventricular (RV) lead positioning on clinical outcome of BiV.

Methods And Results: A total of 99 patients with symptomatic heart failure and implantation of BiV system were included.

Ventricular activation patterns during different pacing modes. An insight from electroanatomical mapping.

Background: Biventricular pacing (BiV) is employed as the current standard for cardiac resynchronisation therapy. Other pacing modalities have been proposed as alternatives; however, data on changes in electrical activation sequence caused by pacing from various sites are limited.

Aim: To describe changes in activation patterns during different ventricular pacing modes in patients with chronic heart failure.

Percutaneous extraction of a fractured permanent pacemaker lead with no free end.

From various points of view abandoned or displaced permanent pacemaker leads should be extracted in indicated cases using a broad spectrum of catheter-based techniques. We describe a relatively easy extraction procedure of almost the whole pacemaker lead, which broke near the pulse generator and migrated into right-heart chambers; so both ends were indwelling. The described procedure was undertaken using a simple homemade nitinol-based extractor.

The spectrum of inter- and intraventricular conduction abnormalities in patients eligible for cardiac resynchronization therapy.

Although cardiac resynchronization therapy (CRT) has clearly demonstrated its clinical benefit in patients with congestive heart failure (CHF) and intraventricular conduction abnormalities, selection of eligible patients and/or optimal pacing site are still a matter of debate. The aim of the study was to analyze the spectrum of conduction abnormalities in CRT candidates. A total of 26 patients (mean age 62 +/- 9 years) with CHF and conduction disturbances (QRS > or = 130 ms) were studied.

Surgical ablation of post-infarction ventricular tachycardia guided by mapping in sinus rhythm: long term results.

Objective: Some patients after myocardial infarction have an increased risk of malignant ventricular tachyarrhythmias (VTA) or sudden cardiac death. The aim of the study was to evaluate long-term results of surgical ablation of an arrhythmogenic substrate guided by simplified intraoperative mapping of pathological ventricular electrograms during sinus rhythm.

Methods: The study population consisted of 77 patients (9 women; mean age 62.

Technical aspects of implantation of LV lead for cardiac resynchronization therapy in chronic heart failure.

The goal of this study was to analyze total procedural and fluoroscopic time during initial experience with implantation of LV lead in a single center, and to assess the performance of electrophysiologically-guided approach for cannulation of the coronary sinus (CS) in a subsequent period. Over an initial period of 29 months, a total of 46 attempts to implant biventricular pacing system were revised. During the first phase, only one type of LV electrode was available for three implanters (11 attempts).

Percutaneous extraction of a severed and frayed permanent pacing lead.

From the point of view of established practice, redundant permanent pacing leads have been abandoned or extracted using various catheter-based procedures. An unusual complication was caused by failed surgical lead extraction resulting in electrode severing and wire unbraiding with subsequent induction of electric interaction between the metallic, noninsulated part of the lead fragment and the defibrillating electrode. This interaction was sensed and detected by the ICD system.

Clinical application of electroanatomical mapping in the characterization of "incisional" atrial tachycardias.

Unlabelled: Scar tissue after surgical procedures for congenital heart disease may create a complex arrhythmogenic substrate and expose patients to the risk of "incisional" tachycardia. We report the usefulness of electroanatomical mapping in the characterization of reentrant circuits and identification of sites of successful radiofrequency (RF) ablation.

Methods: Electroanatomical mapping was used to draw activation maps of the right atrium in 6 men and 4 women (mean age 45 +/- 13.

Catheter ablation of ventricular tachycardia following myocardial infarction using three-dimensional electroanatomical mapping.

One challenge encountered during catheter ablation of postinfarction ventricular tachycardia (VT) is the inducibility of multiple VT morphologies associated with variable hemodynamic instability. The clinical usefulness and safety of a three-dimensional electroanatomical mapping in guiding radiofrequency (RF) catheter ablation of VT, used in parallel with a multichannel recording system, was studied in 28 men (mean age = 63.8 +/- 10.