[The echocardiographic assessment of heart activity in paroxysmal tachycardia in children]. / Ekhokardiograficheskaia otsenka deiatel'nosti serdtsa pri paroksizmal'noi takhikardii u detei.

The echocardiograms of 42 children were examined during paroxysmal tachycardia attacks, as well as 15 minutes and 5 days after them. During paroxysms the electrical and mechanical cardiac activity gets dissociated, the end diastolic volume, the stroke index and ejection fraction decrease which is determined by the reduction of the volume load of the left ventricle because of the shortening of the diastolic phase of the cardiac cycle and the lack of the effective systole of the atria. The late diastolic opening of the mitral valve could not be recorded on the echocardiogram. During the interictal period, the most significant disorders of the cardiodynamics and alterations in the anatomical parameters were discovered in senior children suffering from paroxysmal tachycardia for 3 to 5 years and more.