Diastolic function evaluation in children with ventricular arrhythmia. 

Premature ventricular contractions(PVCs) are frequently seen in children. The diastolic function has not been investigated in PVC children. We evaluated the left ventricular diastolic function in PVC children with normal left ventricular systolic function to detect whether potential diastolic function disturbances influence physical performance. In the study group (36 PVCs children) and the controls (33 healthy volunteers). Echocardiographical diastolic function parameters such as left atrial volume index(LAVI), left atrial strains (AC-R, AC-CT, AC-CD), E wave, E’ medial atrial tissue doppler velocity, E/E’ and isovolumic relaxation time (IVRT) were measured. In the CPET, oxygen uptake (VO2max) was registered. Evaluation of diastolic function parameters revealed statically significant differences between the study and control group regarding Edt 176.58 ± 54.8ms vs 136.94 ± 27.8ms,p < 0.01; E/E’12.6 ± 3.0 vs. 6.7 ± 1.0,p < 0.01; IVRT 96.6 ± 19.09ms. vs. 72.86 ± 13.67 ms,p < 0.01, respectively. Left atrial function was impaired in the study group compared to controls: LAVI 25.3 ± 8.2ml/m 2 vs. 19.2 ± 7.5ml/m 2 ,p < 0.01, AC-CT 34.8 ± 8.6% vs. 44.8 ± 11.8%,p < 0.01; AC-R-6.0 ± 4.9% vs. -11.5 ± 3.5%, p < 0.01, respectively. Statistically significant moderate, negative correlation between VO2max and E/E’(r =-0.33, p = 0.02) was found. Left ventricular diastolic function is impaired and deteriorates with the arrhythmia burden increase in PVC children. Ventricular arrhythmia in young individuals may be related to the filling pressure elevation and drive to exercise capacity deterioration.