日本小児循環器学会雑誌 Pediatric Cardiology and Cardiac Surgery

Background: Atrioventricular valve regurgitation (AVVR) has a notable impact on the prognosis of patients with hypoplastic left heart syndrome (HLHS) and right atrial isomerism (RAI).

Methods: The study population comprised two groups: (1) HLHS and RAI group: n＝32 (HLHS＝15, RAI＝17), and (2) normal control group: n＝53. X-plane images of apical four-chamber view and orthogonal plane cutting through the center of annulus were acquired using transthoracic matrix array probe. Speckle-tracking of the two opposing points on the annulus in four-chamber plane and orthogonal plane was performed, and the distances of respective opposing points were consecutively measured along the cardiac cycle. Atrioventricular valve (AVV) area dynamics were classified into three categories according to the areal change pattern during systole in the normal group: Type-1: area decreases during systole; Type-2: area increases during systole; and Type-3: no significant areal change. The HLHS and RAI groups were subdivided into two subgroups according to the grade of AVVR: low-grade AVVR and high-grade AVVR, and the annular dynamics were compared between the groups.

Results: Normal group was classified into the subgroups as follows: Type-1＝22 (42％); Type-2＝24 (45％); and Type-3＝7 (13％). HLHS and RAI group was classified into the following subgroups: Type-1＝4 (13％), Type-2＝7 (24％), and Type-3＝21 (65％). Type-3 was predominant in the HLHS and RAI groups (p＜0.01). The subdivided groups were similarly classified into low-grade AVVR group (n＝16) and high-grade AVVR group (n＝16). Type-3 was predominant in the high-grade AVVR group (p＜0.01).

Conclusions: In patients with single ventricle associated with tricuspid valve or common AVV, significant valve incompetence was observed in those with reduced annular dynamics, suggesting the importance of annular function in the patients.