An annotation-independent algorithm based on electrogram characteristics to guide the identification of ventricular tachycardia isthmuses in patients with structural heart disease.

Background: Criteria such as electrograms voltage or late potentials have been largely utilized in the past to help identify areas of substrate maps that are within the ventricular tachycardia (VT) isthmus; yet their specificity and positive predictive value are quite low. The Lumipoint fractionation tool of the Rhythmia system illuminates regions with fractionated electrograms irrespective of their timing and annotation. We aimed to ascertain whether the use of this tool can rapidly identify areas within VT isthmuses from substrate maps.

One-year outcomes in patients undergoing very high-power short-duration ablation for atrial fibrillation.

Background: The very high-power short-duration (vHPSD) temperature-controlled ablation (vHPSD) improves the efficiency of pulmonary vein isolation (PVI) procedures. We evaluated the procedural and 12-months outcomes in atrial fibrillation (AF) patients undergoing PVI by means of vHPSD ablation. In patients with AF or atrial tachyarrythmia (AT) recurrence undergoing a redo procedure the durability of the PVI was investigated.

[Cardiac resynchronization therapy: mortality, rehospitalization, and procedure-related complications. A three-year single-center observational study within the Italian Health System].

Background: The aim of this study was to evaluate whether the benefit of cardiac resynchronization therapy with an implantable defibrillator (CRT-D) may differ among classes of indications to device therapy.

Methods: All-cause mortality, first hospitalization for non-fatal heart failure, stable improvement of NYHA functional class (responders), and implant-related complications were evaluated retrospectively in 103 patients selected among those (n = 133) who received consecutively CRT-D between 2006 and 2009. Patients were divided into three groups: group IA (n = 65) included patients receiving CRT-D for a class IA indication; group IIa (n = 26) included patients with atrial fibrillation and QRS ≥ 130 ms receiving CRT-D for a class IA indication; nonconventional group (NC) (n = 12) included patients with an indication to defibrillator implantation extended to CRT-D because of NYHA class III-IV and echocardiographic evidence of electromechanical dyssynchrony.

Noninvasive assessment of left ventricular contractility by pacemaker stress echocardiography.

Background: Estimating contractility of the left ventricle with noninvasive techniques is an important yet elusive goal. Positive inotropic interventions are mirrored by smaller end-systolic volumes and higher end-systolic pressures. An increased heart rate progressively increases the force of ventricular contraction (Bowditch treppe or staircase phenomenon).

Biventricular pacing via a persistent left superior vena cava: report of four cases.

Persistence of left superior vena cava (LSVC) is an uncommon finding during pacemaker implantation, which may be particularly relevant in performing LV transvenous pacing. Rarely, it is further complicated by the presence of atresia of the coronary sinus ostium (CSO). This article reports the authors experience with biventricular pacing (Biv-P) in this unusual clinical setting.