Congenital: Atrioventricular Septal Defect
Complete atrioventricular septal defect with absent or diminutive primum component: Incidence, anatomic characteristics, and outcomes

Accepted for the 46th Annual Meeting of the Western Thoracic Surgical Association.
https://doi.org/10.1016/j.jtcvs.2021.06.041Get rights and content
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Abstract

Background

Repair of complete atrioventricular septal defect with absent or diminutive primum defect is challenging because of atrial septal malposition and abnormal anatomy of the left atrioventricular valve. We sought to define the incidence, anatomy, and surgical outcomes of this entity.

Methods

We identified all patients in our institutional database presenting for complete atrioventricular septal defect repair from 2006 to 2018. Operative reports and echocardiograms were reviewed to determine the presence and size of the primum defect, atrioventricular valve anatomy, degree of atrioventricular valve regurgitation, repair method, and complications, including reoperation for atrioventricular valve regurgitation. Functionally univentricular patients and those receiving repair at an outside institution were excluded.

Results

Of 183 patients with complete atrioventricular septal defect, absent/diminutive primum defect occurred in 16 patients (8.7%; 10 absent, 6 diminutive). Six patients (38%) had leftward malposition of the atrium septum on the common atrioventricular valve. The rate of reoperation for left atrioventricular valve regurgitation was 31% (3 early, 2 late), for which preoperative predictors included leftward malposition of the atrial septum onto the common atrioventricular valve (4/6 patients with malposition required reoperation, P = .036, Fisher exact test). One patient exhibiting this risk factor died. The overall rate of moderate or greater left atrioventricular valve regurgitation on the most recent postoperative echocardiogram was 13% (2/16 patients; median follow-up, 141 days; range, 3-2236 days).

Conclusions

Complete atrioventricular septal defect with absent or diminutive primum defect is a unique variant of complete atrioventricular septal defect for which the risk of reoperation for left atrioventricular valve regurgitation after complete repair is high and risk factors include leftward malposition of the atrial septum on the common atrioventricular valve.

Key Words

atrioventricular valve defect
congenital cardiac surgery

Abbreviations and Acronyms

ASD
atrial septal defect
AVSD
atrioventricular septal defect
AVV
atrioventricular valve
CAVSD
complete atrioventricular septal defect
CPB
cardiopulmonary bypass
PFO
patent foramen ovale
TEE
transesophageal echocardiogram
TTE
transthoracic echocardiogram
VSD
ventricular septal defect

Cited by (0)

Institutional Review Board Approvals: No. STUDY0001624, approval date January 9, 2019; No. MODCR00001591, approval date January 27, 2021. Informed consent waived (retrospective, no patient contact).