Persistent Atrial Fibrillation And Atrial Flutter Complicated By Tachycardiomyopathy Because Of Intermittent Conduction Through Accessory Pathway.

The term tachycardiomyopathy refers to a specific form of tachycardia-related cardiomyopathy caused by supraventricular or ventricular tachyarrhytmias that are both associated with ventricular rates higher than 120 bpm. The arrhythmias which are most frequently associated with these forms of heart disease are atrial fibrillation and atrial flutter, particularly found in the elderly population. The most frequent clinical manifestation is heart failure. In this case we are reporting a clinical case of a patient that came to our attention because of an episode of heart failure associated with atrial fibrillation and atrial flutter. The patient had also prolonged and repetitive strips of rapid conduction with wide QRS morphology. We don't know if the cause is pre excitation or ectopia. We showed that those strips of tachycardia with wide QRS, particularly when they were associated with atrial flutter, were so fast and consistent to determine the left ventricular contractile dysfunction; we showed also that those strips of wide complex tachycardia were caused by pre-excitation through an accessory right posteroseptal pathway and supported by the reentry circuit of common atrial flutter. The block of conduction through the accessory pathway and the elimination of atrial arrhythmia allowed the regression of left ventricular contractile dysfunction. We believe that this case is interesting because it shows that there is a strict continuity between sophisticated electrophysiological mechanisms and clinical manifestation.

[Natriuretic peptides and the heart. Critical review and application]. / Peptidi natriuretici e cuore. Revisione critica ed applicazioni.

This paper deals with a literature survey on natriuretic peptides (NP) and their clinical use in prognostic stratification and therapy of arterial hypertension and cardiac failure. After a brief historical introduction, the phylogenesis of NP is analyzed and the reasons of their preservation in the evolution are emphasized. The biochemistry of the NP is then treated, and the structure, synthesis, mechanism of cellular action and systems of regulation are analyzed. Subsequently, the authors have analyzed the physiology of the NP as well as their hemodynamic and biohumoral effects and actions on the central nervous system. A literature review on the significance of NP in arterial hypertension, on their usefulness as indicators of damage and on their therapeutic practice is then made. In particular, the possible future applications in the prevention of atherosclerotic damage are analyzed. The significance of NP and of their metabolites in heart failure and the prognostic implication of these peptides particularly in ischemic heart failure are then discussed. The most important papers on this topic are described. Finally the studies on the use of NP in the therapy of heart failure are analyzed and a guide on research of this topic is defined.