G. Spadacini

Electroanatomic Analysis of Sinus Impulse Propagation in Normal Human Atria

Sinus Impulse Propagation in Normal Human Atria. Introduction: Better understanding of atrial propagation during sinus rhythm (SR) in normal hearts under the most normal physiologic conditions may be propaedeutic to pathophysiologic studies of complex atrial arrhythmias. In this study, qualitative and quantitative analyses of sinus impulse propagation in both atria were performed by electroanatomic mapping in patients with no organic heart disease who were undergoing an electrophysiologic procedure.

Comparison of single premature versus continuous overdrive stimulation for identification of a protected isthmus in macro-reentrant atrial tachycardia circuits

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Complex Supraventricular Tachycardia Ablation: What Is the Role of Alternative Technology?

Radiofrequency catheter ablation is a safe and effective treatment for curing supraventricular tachycardias (SVT), including those related to different forms of atrioventricular (AV) nodal reentry and to the Wolff-Parkinson-White syndrome. Although this treatment is largely considered as a first-line therapy for these tachycardias, under some circumstances the safety and/or the effectiveness of the procedure might be endangered. This review will focus on the difficulties that can be met during SVT catheter ablations, and on the role of special tools and new technologies in improving the success rate and reducing the complications.

Ablation of Atrial Fibrillation: Are We Still “Learning While Burning”?

During the 1990s, the concept of “learning while burning” was introduced and developed by Callans et al. in a series of articles [1–3]. In these papers, the authors expressed the idea that catheter ablation (burning), far from marking the end of pathophysiological investigation, may be viewed as a tool to provide unique and new information (learning) about arrhythmia substrates. Earlier, since with the introduction of catheter ablation electrophysiology had focused more and more on procedural efficacy and case volume, Smith and Cain [4] showed the possible detrimental development from electrophysiology to “electrotechnology,” with loss of research, investigation, and learning-teaching, which has always surrounded the field of cardiac electrophysiology. Recently, the “learning while burning” concept has been revisited and applied [5] to the pathophysiology of atrial fibrillation, where, although the experience of pulmonary vein ablation contributes to the increase of our knowledge day by day, much still remains to be understood of the ultimate mechanism of the arrhythmia. On the other hand, it has been pointed out that trying to elucidate the mechanism of human atrial fibrillation appears as frustrating as being the translator at the Tower of Babel [6], meaning that the pathophysiology of this arrhythmia may present multiple aspects in different clinical and electrophysiological settings, difficult to investigate in humans. In the present paper, we attempt to revisit some aspects of the experience in catheter ablation of atrial fibrillation, trying to point out what we have learnt and what we still have to learn to improve our knowledge and, hopefully, results. For reasons of brevity, only catheter ablation for electrical isolation of the pulmonary veins with an electrophysiological end-point [7] is considered.