Right atrial function late after biventricular repair of pulmonary atresia or stenosis with intact ventricular septum

Abstract

Right ventricular (RV) restrictive physiology and diastolic dysfunction reported in patients after repair of pulmonary atresia with intact ventricular septum (PAIVS) and pulmonary stenosis (PS) may alter right atrial (RA) function. Right atrial dysfunction may impact on P-wave indices and provide substrate for development of atrial arrhythmias. This study aimed to interrogate RA function in patients after biventricular repair of PAIVS and PS and to explore their relationships with RV diastolic function and P-wave indices.

Sixteen PAIVS patients aged 26±5 years, 20 PS patients aged 26±8 years, and 20 age-matched healthy subjects were studied. Right atrial function was assessed using two-dimensional (2D) speckle tracking echocardiography (STE) for quantification of peak positive, negative, and total strain, and strain rates at ventricular systole (aSRs), early diastole (aSRed), and atrial contraction (aSRac). Right ventricular diastolic function was assessed by pulsed-wave and tissue Doppler interrogation and 2D STE-derived diastolic strain rates. Restrictive RV physiology was defined by the presence of diastolic antegrade pulmonary flow. Maximum P-wave duration and P-wave dispersion were measured from 12-lead electrocardiograms.

Compared with controls, PAIVS and PS patients had significantly lower RA positive and total strain, aSRs and aSRed (all p<0.05). Right atrial strain values were worse in PAIVS patients (p<0.05), who had a higher prevalence of restrictive RV physiology (81% vs 32%, p<0.001), than PS patients. Parameters of RV diastolic function including transtricuspid early (E) and late (A) diastolic inflow velocities, E/A ratio, early diastolic tricuspid annular velocity (e), early to late diastolic annular velocity ratio, E/e ratio, and RV early diastolic strain rate were found to correlate significantly with RA positive and total strain and aSRed (all p<0.05). Maximum P-wave duration and P-wave dispersion increased progressively across the control, PS, and PAIVS groups (p for trend <0.001). Both P-wave indices correlated negatively with RA positive strain, total strain, and aSRed (all p<0.05).

Right atrial dysfunction occurs in patients long-term after biventricular repair of PAIVS and PS, worse so in the PAIVS group, and is associated with RV diastolic dysfunction, longer P-wave duration, and greater P-wave dispersion.