[Lesions caused by techniques of endocavitary ablation using high frequency currents: anatomo-pathological aspects]

Anatomopathological studies have considerably increased our understanding of the ablative technique by radiofrequency current. They have provided information on the nature, extent and time dependency of the lesions induced. Despite variable results according to whether the experiments were performed in vitro or in vivo, a correlation has been observed between the volumes of the lesions and the energies used. One factor is unquestionable: monitoring the temperature allows better control of the lesion size than monitoring current intensity. However, other technical points are essential for this control such as ensuring good contact between the catheter and the endocardium and the definition of the optimal surface area of the electrode. Now that the conditions of efficacy and security of ablation by high frequency currents are known, anatomopathological studies in man have become rare. These studies, which will take a long time to perform due to the very nature of the technique and pathologies treated, should provide interesting anatomo-electrical comparisons to increase our understanding of certain arrhythmias.