Left Valvar Morphology is Associated with Late Regurgitation in Atrioventricular Canal Defect
Ho DY, Katcoff H, Griffis HM, Mercer-Rosa L, Fuller SM, Cohen MS.
Ann Thorac Surg. 2020 Feb 20. pii: S0003-4975(20)30219-8. doi: 10.1016/j.athoracsur.2020.01.012. [Epub ahead of print]
PMID: 32088289
Select item 32079620
Take Home Points:
- Residual left atrioventricular valve regurgitation (LAVVR) is commonly seen after surgery.
- Complex leaflet morphology, which results in complex valve repair is associated with early LAVVR.
- However, after controlling the weight at surgery, presence of genetic syndrome and bypass time, multivariate analysis showed presence of widely spaced papillary muscles and larger mural leaflet area were associated with late LAVVR.
- There may be other pathology, other than the progression of LAVVR which is responsible for late onset LAVVR.
Commentary from Dr. M.C. Leong (Kuala Lumpur, Indonesia), section editor of ACHD Journal Watch: Left atrioventricular valve regurgitation (LAVVR) following repair of atrioventricular canal repair is not uncommon and it causes significant morbidity. The authors sought to characterise the left mural leaflet and papillary muscle morphology in patients with atrioventricular canal defects to determine if variation in leaflet anatomy were risk factors for postoperative LAVVR.
This is single-centre, retrospective review of all patients with complete or transitional atrioventricular canal who underwent repair from January 2011 until December 2016. During this period, 156 patients, of whom 84% had complete atrioventricular septal defect were included (Table 1). Majority of these patients underwent repair using a two-patch technique and cleft closure. Of these patients, 58 (37%) patients had significant early postoperative LAVVR. 16 (10%) patients underwent left atrioventricular valve reoperation or replacement. In 11 of these patients, reoperation occurred within the first 3 months. Four patients required two or more reoperation and of these, 3 eventually underwent mechanical valve replacement. In the long term, 30 of 93 (32%) had significant LAVVR (Figure 3).
Longer bypass time, deep hypothermia circulatory arrest, and repeat bypass runs were associated with early postoperative LAVVR but not late LAVVR (Table 5). This underscored the surgical complexity as the cause for early postoperative LAVVR. However, late LAVVR was associated with papillary morphology. The authors characterised the morphology into (a) widely spaced papillary muscle, (b) closely spaced papillary muscles, (c) Dominant papillary muscle, (d) mural leaflet area : overall left atrioventricular valve area and cleft length: overall left atrioventricular valve diameter (Figure 2). They noted that after controlling the weight at surgery, presence of genetic syndrome and bypass time, multivariate analysis showed presence of widely spaced papillary muscles and larger mural leaflet area were associated with late LAVVR (Table 6).
The results of the study came as a surprise for a few reasons. Firstly, patients with complex valve morphology was associated with early but not late LAVVR suggesting that late AVVR may not be a progression of the early LAVVR. Secondly, patients with widely spaced papillary muscles usually has a larger mural leaflet area which generally confer less atrioventricular valve regurgitation post-operatively but has been shown to be associated to late LAVVR, which suggest other pathology being the cause the late LAVVR. Unfortunately, the study was not powered to assess these causes of the late LAVVR.
