Abnormalities of right ventricular long axis function after atrial repair of transposition of the great arteries

BACKGROUND—While volume derived global indices of right ventricle (RV) function are frequently abnormal after the Mustard procedure, the mechanism for these abnormalities is poorly understood. RV muscle fibres are predominantly arranged longitudinally and thus indices derived in the long axis may better describe RV function.
METHODS—20 survivors of the Mustard operation were studied (age 7.8-37.3 years, median 14.2 years). Long axis recordings from the apical four chamber view were obtained with the M mode cursor positioned through the lateral angle of the tricuspid valve annulus. M mode traces were recorded on paper and later digitised to derive total atrioventricular ring excursion, peak lengthening rate, and peak shortening rate. These data were averaged and compared with control data for the normal RV and left ventricle (LV).
RESULTS—RV total atrioventricular ring excursion was lower than that for the RV (p < 0.0001) or LV (p < 0.005) of controls. Peak lengthening rate was lower than the normal RV (p < 0.0001) and LV (p < 0.0001) rates. Furthermore, peak shortening rate was less than that of normal RV (p < 0.0001) and normal LV (p < 0.005) controls.
CONCLUSION—Systemic RV long axis function is notably reduced compared with that of either the normal subpulmonary RV or the systemic LV. This presumably reflects the response of the predominantly longitudinally arranged myocardial fibres to increased afterload. However, such measurements may provide a more sensitive marker for progressive changes in global function during long term follow up.


Keywords: Mustard procedure; right ventricular function; transposition of the great arterie

Can atrioventricular septal defects exist with intact septal structures?

The hallmark of an atrioventricular septal defect (AVSD) is a common atrioventricular junction, giving rise to a trileaflet left atrioventricular valve. AVSDs have the potential for interatrial shunting alone, interventricular shunting alone, or both. AVSDs without interatrial or interventricular communications have been identified at postmortem examination, but there are no reports of AVSDs with intact septal structures diagnosed in life. Six patients are described with AVSD and intact atrial and ventricular septa diagnosed echocardiographically. This report shows that AVSDs can exist without interatrial or interventricular communications and that the characteristic feature of this condition, the common atrioventricular junction with a trileaflet left atrioventricular valve, can be diagnosed in life by using cross sectional echocardiography. AVSDs with intact septal structures may be more common than previously described

Serial changes in longitudinal strain are associated with outcome in children with hypoplastic left heart syndrome

Introduction: Hypoplastic Left Heart Syndrome (HLHS) has high mortality and morbidity and systemic right ventricle (RV) dysfunction may play a key-role. Study aim is to evaluate the accuracy of speckle-tracking echocardiographic (STE) assessment of RV deformation and 2D standard echo parameters in predicting outcome in HLHS patients. Methods: We studied 27 HLHS patients (17 male) who successfully completed Norwood palliation. All the patients underwent in-hospital interstage stay. Serial echocardiographic assessment was performed: baseline, one-month after Norwood, three-months after Norwood, one-week before bidirectional cavopulmonary anastomosis (BCPA) and two-months after BCPA. From the apical view we measured: tricuspid annulus peak systolic excursion (TAPSE), fractional area change (FAC), longitudinal strain (LS) and strain rate (LSR). Results: After a mean follow-up of 1.18 (\ub1 1.16) years, 8 out of 27 of the included patients met the composite endpoint of death/heart transplant (HT). At pre-Norwood assessment, there was no difference in echo measurements between survivors and patients with events. In death/HT group TAPSE and LS declined already one-month after Norwood procedure: TAPSE 645 mm had good sensitivity (85.71%) and moderate specificity (63.16%) for death/HT (AUC = 0.767); a decrease of LS > 8.7% vs baseline showed 100% sensitivity and 84.21% specificity for death/HT (AUC = 0.910). At multivariate analysis, one-month-after-Norwood LS drop >8.7% was the best predictor of outcome (P = 0.01). Conclusions: RV dysfunction in HLHS carries prognostic value. Our findings encourage serial measurements of RV function to identify the subgroup of HLHS patients at higher risk. In our experience, 06 LS showed the best predictive value