AUTOMATIC-ANALYSIS OF HIGH-RESOLUTION ATRIAL ACTIVATION IN MITRAL-VALVE-STENOSIS

High resolution P-waves of 28 patients having a mean age of 45 years a nd affected by isolated mitral valve stenosis (nine of whom showed par oxysmal atrial fibrillation) have been compared with those obtained fr om 30 healthy subjects about 35 years old. Our primary aim was to char acterize the signal-averaged P-wave in mitral valve stenosis. Paramete rs which differed between the two groups in time domain analysis were the P-wave duration, the abscissa of the maximum positive voltage ampl itude, the peak-to-peak amplitude and the integrated voltage-time prod uct, which turned out to be greater in the patient class than in the h ealthy set; furthermore, in the frequency domain analysis, amplitudes in the range from 37 to 60 Hz were greater in healthy subjects than in patients. A successive analysis carried out to predict those patients with mitral valve stenosis who are at risk of developing paroxysmal a trial fibrillation showed that the P-wave duration and the amplitudes (in the range 60-106 Hz) were the most distinctive parameters, but, un fortunately, without any significant difference with respect to those of patients with mitral valve stenosis alone. Finally, some correlatio ns between the age, the P-wave duration and the left atrial diameter o f patients, were revealed to exist only in patients affected by episod es of atrial fibrillation.