A novel repair for patients with atrioventricular septal defect requiring reoperation for left atrioventricular valve regurgitation

Reoperations After Repair for Atrioventricular Septal Defects: >25 Years Experience at a Single Center

Our aim was to evaluate the total burden of reoperations after previous repair for atrioventricular septal defects, including long-term survival and identify risk factors for reoperation. All patients with surgical correction for atrioventricular septal defect (AVSD) 1993- 2020 underwent a follow-up in October 2020. Clinical data were obtained by retrospective review and evaluated with Kaplan-Meier and competing risk analysis. Of 477 patients who underwent initial repair, 53 patients (11.1%) underwent a total of 82 reoperations. The perioperative mortality at reoperation was 3.8% (2/53). There were no late deaths (0/51) during follow-up. In patients requiring reoperation for left atrioventricular valve regurgitation, a re-repair was performed in 90% (26/29) at first attempt. Estimated overall survival was 96.2 ± 2.6% (95% CI 91.2-100) in the Any reoperation group and 96.7 ± 0.9% (95% CI 94.9-98.5) in the No reoperation group at 20 years (P = 0.80). The cumulative incidence function of Any reoperation (with death as competing risk) was 13.0% (95% CI 9.4-16.5) at 20 years. Independent risk factors for Any reoperation included severe mitral regurgitation after primary repair (HR 40.7; 95% CI 14.9-111; P < 0.001). The risk of perioperative mortality in AVSD patients undergoing reoperation was low in the present study. Long-term survival was very good and not significantly different when compared to patients who did not need reoperation. Re-repair for left atrioventricular valve regurgitation was possible in most cases and showed long-term durability. Our data suggest that reoperations after primary repair of AVSD have very good long-term outcomes when performed at a high-volume pediatric cardiac surgery center.

Repair of complete atrioventricular canal defects: Early and midterm results and comparison of the left anterior leaflet augmentation technique with traditional technics

BACKGROUND

Complete atrioventricular septal defects (CAVSD) include a variable spectrum of congenital malformations with different forms of clinical findings. We examined early and midterm outcomes, the need for reoperation, postoperative residual AV valve regurgitation, and other risk factors after various CAVSD repairs.

METHODS

Between 2014 and 2018, we have performed 89 isolated CAVSD repairs. We retrospectively reviewed the patients' medical records. Patients were divided into three groups according to their repair techniques modified one patch repair (MP) (n = 16); two patch repair (TP) (n = 49); and left anterior leaflet augmentation (ALA) technique (n = 24).

RESULTS

Eighty patients (89.8%) survived hospital discharge. Early mortality rates were three (18.8%) in the group MP, five (10.2%) in the group TP, and one (4.2%) in the group ALA. Thirteen patients died during the follow-up period. Late mortality rates were three (18.8%) in the group MP, four (16.6%) in the group ALA, and six (12.2%) in the group TP. The mean follow-up time was 35.9 ± 22.97 months (range: 0.3-77 months). The morbidity and mortality results were similar between-group TP and ALA but worse in the MP group. Low body weight (<4 kg) and younger age at surgery (<4 months) were found to be risk factors on mortality by univariate and multivariate analysis. Surgical technic was not found to be an independent risk factor.

CONCLUSION

In our series, TP and ALA techniques had satisfactory results in early and midterm periods. Younger age and small bodyweight might increase early mortality and the need for reoperation.

Double orifice and atrioventricular septal defect: dealing with the zone of apposition†

OBJECTIVES

A double orifice of the left atrioventricular valve (LAVV) associated with atrioventricular septal defects (AVSD) can significantly complicate surgical repair. This study reports our experience of AVSD repair over 3 decades, with special attention to the zone of apposition (ZoA) of the main orifice, and presents a technique of hemivalve pericardial extension in specific situations.

METHODS

We performed a retrospective study from 1987 to 2016 on 1067 patients with AVSD of whom 43 (4%) had a double orifice, plus 2 additional patients who required LAVV pericardial enlargement. Median age at repair was 1.3 years. Mean follow-up was 8.2 years (1 month-32 years).

RESULTS

Associated abnormalities of the LAVV subvalvular apparatus were found in 7 patients (5 parachute LAVV and 2 absence of LAVV subvalvular apparatus). ZoA was noted in 4 patients (9%): partially closed in 15 (35%) and completely closed in 24 (56%). Four patients required, either at first repair or secondarily, a hemivalve enlargement using a pericardial patch without closure of the ZoA. The early mortality rate was 7% (n = 3), all before 2000. Two patients had unbalanced ventricles and the third had a single papillary muscle. There were no late deaths. Six patients (14%) required 7 reoperations (3 early and 4 late reoperations) for LAVV regurgitation and/or dysfunction, of whom 4 (9%) required mechanical LAVV replacement (all before 2000). Freedom from late LAVV reoperation was 97% at 1 year, 94% at 5 years and 87% at 10, 20 and 30 years. Unbalanced ventricles (P = 0.045), subvalvular abnormalities (P = 0.0037) and grade >2 LAVV postoperative regurgitation (P = 0.017) were identified as risk factors for LAVV reoperations. Freedom from LAVV mechanical valve replacement was 95% at 1 year, 90% at 5 years and 85% at 10, 20 and 30 years. An anomalous LAVV subvalvular apparatus was identified as a risk factor for mechanical valve replacement (P = 0.010). None of the patients who underwent LAVV pericardial extension had significant LAVV regurgitation at the last follow-up examination.

CONCLUSIONS

Repair of AVSD and double orifice can be tricky. Preoperative LAVV regurgitation was not identified as an independent predictor of surgical outcome. LAVV hemivalve extension appears to be a useful and effective alternate surgical strategy when the ZoA cannot be closed.

Mid-term outcome with pericardial patch augmentation for redo left atrioventricular valve repair in atrioventricular septal defect†

OBJECTIVES

Recurrent left atrioventricular valve (LAVV) regurgitation after atrioventricular septal defect (AVSD) repair is a difficult technical issue. This study exposes the various techniques successively employed to repair the recurrent LAVV regurgitation and their different outcomes. Emphasis however will be put on the new technique used in our unit called cleft patch augmentation, which has been used continuously since 1998 in the anatomical context of normal papillary muscles (NPMs).

METHODS

This is a retrospective follow-up study using a Cox regression model for risk analyses from November 1991 to July 2008, including 45 patients who underwent reoperation for LAVV regurgitation after AVSD repair. Of those, 3 patients were lost to follow-up; therefore, 42 patients were included in the study. With regard to the AVSD morphology, there were partial AVSD in 12, complete AVSD in 30.

RESULTS

Age at the primary valve repair was 1.5 ± 2.1 years and the time span to the reoperation was 7.1 years in median (0.41-12.3 years). Age at the first reoperation was 10.1 ± 6.8 years. Median follow-up after the reoperation was 7.4 years. Three patients died in the follow-up period. Freedom from second reoperation at 10 years was 72.8% [59.5-89.0% of 95% confidence interval (CI)]. Of 37 patients with NPMs, freedom from reoperation at 10 years was 59.4% (37.2-94.7% 95% CI) in cleft closure group whereas, in the cleft patch augmentation group, it was 92.3% (78.9-100% 95% CI) (P = 0.04). Five patients required valve replacement.

CONCLUSIONS

Surgical result for the redo LAVV repair had good outcomes. In the NPM group, the cleft patch augmentation technique had better results. Various techniques may have to be performed in combination according to the morphological features.

Surgical outcome of reoperation due to left atrioventricular valve regurgitation after previous correction of complete atrioventricular septal defect

OBJECTIVES

The aims of this study were to evaluate the early and late outcomes in patients undergoing reoperation due to left atrioventricular valve regurgitation (LAVVR) after initial complete repair (ICR) of complete atrioventricular septal defect (CAVSD).

MATERIALS AND METHOD

Between January 1990 and April 2013, 45 consecutive patients underwent reoperation due to severe LAVVR. The mean age was 7.5 ± 6.2 years. Associated LAVV malformations were found in 22 (49%) patients and associated cardiac malformations in 18 (40%). The mean follow-up was 6.8 ± 2.6 years.

RESULTS

LAVV repair was possible in all patients. There were two hospital deaths (4.5%). Ten patients (22%) required a second reoperation due to severe LAVVR at mean 7.5 ± 8.4 months after the first reoperation. The actuarial overall survival and free-reoperation survival rates at one, three, and five years were 95.4%, 92.8%, and 92.8% and 89%, 80.5%, and 72%, respectively. Multivariate analysis revealed that the associated cardiac malformations, LAVV leaflet prolapse or detachment from the septal patch, associated LAVV malformations, and post-first correction LAVVR grade ≥ 2 were strong predictors for poor overall free-reoperation survival in patients undergoing reoperation due to LAVVR after ICR of various forms of ACVSD.

CONCLUSIONS

Patients with severe LAVVR post-ICR of CAVSD may undergo reoperation with acceptable postoperative mortality and morbidity; however, they are at an increased risk for developing postoperative LAVVR and subsequent reoperation.

Reoperations for left atrioventricular valve dysfunction after repair of atrioventricular septal defect

OBJECTIVES

Postoperative left atrioventricular valve (LAVV) dysfunction is known to be the principal risk factor influencing outcome after repair of all types of atrioventricular septal defect (AVSD). The purpose of the present study was to identify the risk factors for reoperation and to assess the outcomes after reoperation for LAVV dysfunction.

METHODS

Records of 412 patients who underwent anatomical repair for different types of AVSD from January 2000 to July 2012 were reviewed. The study group (n = 60) included 13 additional patients for whom repair ± LAVV reoperation was performed in a primary institution. Outcomes, independent risk factors, reoperation and death were analysed.

RESULTS

There were 7 early, (1.7%) and 1 late death. Forty-seven (11.4%) required 64 reoperations for LAVV dysfunction. The median delay for the first LAVV reoperation was 3.5 months (range: 5 days to 10.0 years). Unbalanced ventricles with small left ventricle [odds ratio (OR) = 4.06, 95% confidence interval (CI): 1.58-10.44, P = 0.004], double-orifice LAVV (OR = 5.04, 95% CI: 1.39-18.27, P = 0.014), prior palliative surgery (OR = 3.5, 95% CI: 1.14-10.8, P = 0.029) and discharge echocardiography documenting LAVV regurgitation grade >2 (OR = 21.96, 95% CI: 8.91-54.09, P < 0.001) were found to be independent risk factors for LAVV reoperation. Twelve-year survival and freedom from LAVV reoperation rates were, respectively, 96.1% (95% CI: 94.1-98.1) and 85.8% (95% CI: 81.3-90.3). Survival was significantly worse in patients who underwent LAVV reoperation (P < 0.001) and in those who underwent valve replacement vs valve repair (P = 0.020).

CONCLUSION

After AVSD repair, LAVV dysfunction appears to be the principal factor that influences outcome. It can usually be managed by repair. Need for multiple reoperations is not uncommon. Long-term outcome in patients with repaired LAVV is favourable.

Early outcomes and prognostic factors for left atrioventricular valve reoperation after primary atrioventricular septal defect repair

This study aimed to identify early outcomes of and prognostic factors for left atrioventricular valve (LAVV) reoperation after primary atrioventricular septal defect (AVSD) repair. A retrospective cohort study was performed using the Pediatric Cardiac Care Consortium database, which included 370 patients with previously repaired AVSDs who subsequently underwent LAVV reoperation between 1982 and 2007. Of these patients, 243 underwent LAVV repair, and 127 underwent LAVV replacement. Median time to first reoperation after primary repair was 0.67 years in the repair subgroup and 0.18 years in the replacement subgroup. Thirty-day survival was significantly poorer in the replacement subgroup compared with the repair subgroup (P = 0.0002). In multivariable analysis, independent predictors of earlier time to valve replacement included presence of Down syndrome and postoperative left atrioventricular valve stenosis. Independent predictors of in-hospital death after valve replacement included presence of Down syndrome (hazard ratio [HR] 2.34, 95% CI 1.19-4.58) and prosthetic valve size-to-weight ratio >3 mm/kg (HR 3.02, 95% CI 1.52-6.01). The identification of a subgroup of previously repaired AVSD patients at high risk for early postoperative death after LAVV replacement suggests that for these patients, a low threshold for detailed hemodynamic monitoring and/or reintervention for hemodynamic aberrations is warranted.

Partial atrioventricular canal: pitfalls in technique

Partial atrioventricular (AV) canal represents approximately 25% of all AV septal defects. While often grouped with secundum ASD from the perspective of cardiopulmonary physiology, clinical presentation, and timing of surgical correction, their optimal management truly requires an understanding of their anatomic similarities to other forms of common AVC defects. By most measures, outcomes for surgical management of partial AV canal has improved over the last four decades, though some aspects of these defects continue to pose important challenges. Current experience has witnessed the reduction in early mortality and only rare complete heart block. Left AV valve dysfunction remains the most common indication for reoperation (10%) with LVOT stenosis the next most common reason (10% to 15% incidence, 5% to 10% reoperation rate). It is important to understand in this population that postoperative left AV valve problems and LVOT stenosis may be intimately linked, both from an etiologic standpoint, and with respect to their management.

Complex atrioventricular canal

Complex forms of atrioventricular (AV) canal (C) such as; AVC with left ventricular outflow tract obstruction, tetralogy of Fallot with complete AVC, double orifice left AV valve, unbalanced complete AVC, and single ventricle patients with common AVC valve require careful preoperative planning and special techniques. This review will explore these technical modifications and outcomes for repair of complex variants of AVC. Optimal results will be achieved using an individually tailored approach that is guided by careful evaluation of the preoperative studies, precise operative technique, and intraoperative assessment of the reconstructed AV valve, as well as a willingness to re-intervene should the postoperative course not proceed as anticipated.

Three-dimensional Echocardiography Improves the Understanding of the Mechanisms and Site of Left Atrioventricular Valve Regurgitation in Atrioventricular Septal Defect

OBJECTIVES

The purpose of this study was to determine whether 3-dimensional echocardiography (3DE) provides additional information regarding the mechanisms and sites of left atrioventricular valve regurgitation in atrioventricular septal defect compared with transesophageal 2-dimensional echocardiography (2DE).

METHODS

Eleven patients with a median age of 5.4 years (2.9-11.6 years) and a median weight of 16.8 kg (13.7-38.3 kg) with an atrioventricular septal defect underwent simultaneous transesophageal 2DE and 3DE before operation.

RESULTS

The 2DE-3DE agreement for the assessment of the superior and mural leaflet size was 72.7%. The 2DE-3DE agreement for coaptation failure, a residual or primary cleft, and commissural abnormalities as a mechanism of regurgitation were 72.7%, 63.6%, and 36.4%, respectively. For jet sites the 2DE-3DE agreement was 63.6% for a commissural and central location.

CONCLUSION

Three-dimensional echocardiography provides new and superior data regarding the mechanisms and sites of left atrioventricular valve regurgitation in atrioventricular septal defect.

The Impact of Patch Augmentation on Left Atrioventricular Valve Dynamics in Patients with Atrioventricular Septal Defects: Early and Midterm Follow-up

OBJECTIVE

Left atrioventricular valve pericardial patch may prevent valve replacement. We assessed patch annular dynamics compared with conventional repair and normal annuli.

METHODS

Transesophageal 3-dimensional echocardiography was acquired preoperatively and postoperatively in atrioventricular septal defects (n = 10, 5 patch, 5 conventional repair). Real-time 3-dimensional annular motion at midterm was compared with that of healthy children (n = 10). Parameters were: annular area, perimeter, segmental diameter, bending angle, stenosis, and regurgitation.

RESULTS

Regurgitant jet area ratio decreased in both patient groups. Conventional repair reduced annular area (P = .02). Patch repair showed an annular area larger than normal (P = .01). Control subjects had increased systolic area whereas operative groups showed a reduction. Patch repair had segmental diameters similar to normal whereas conventional repair was inhomogeneous. Annular bending angle was maintained after operation.

CONCLUSION

Patch repair in pediatrics shows durability without shrinkage or expansion. Improved stenosis and regurgitation does not change by midterm. Operation causes increased annular stiffness and diminished compliance. Neither technique establishes normal annular eccentricity.

Utilization of double-orifice valve plasty in correction of atrioventricular septal defect

BACKGROUND

Atrioventricular valve regurgitation represents the principal indication for reoperation after repair of atrioventricular septal defect. Deciding how to correct atrioventricular valve regurgitation is challenging in some cases because of the complexity of the anatomic features. This report deals with our surgical experience in using a double-orifice valve plasty technique in cases with atrioventricular septal defect.

METHODS

From August 2002 to August 2004, 8 patients underwent double-orifice valve plasty in surgical correction of atrioventricular septal defect. Anatomic types were partial (6 patients), intermediate (1 patient), and complete (1 patient). After the mitral cleft was closed, moderate to severe atrioventricular valve regurgitation was still present in these patients. Double-orifice valve plasty was used in the mitral valve in 7 patients and in the tricuspid valve in 1.

RESULTS

No hospital deaths or postoperative morbidity occurred. The follow-up ranged from 6 months to 30 months (median, 14.4 months). No or trivial atrioventricular valve regurgitation was found in 6 patients and mild atrioventricular valve regurgitation was present in 2.

CONCLUSIONS

Double-orifice valve plasty is an easy and effective additional procedure for children and for adult patients who have moderate or severe atrioventricular valve regurgitation after repair of atrioventricular septal defect.

Three-dimensional echocardiography improves the understanding of left atrioventricular valve morphology and function in atrioventricular septal defects undergoing patch augmentation

OBJECTIVES

We sought to address the role of 3-dimensional echocardiography in the evaluation of the left atrioventricular valve in children with an atrioventricular septal defect who underwent patch augmentation of their valve for either regurgitation or left ventricular outflow tract obstruction.

METHODS

Five children whose ages ranged between 4.5 and 9.2 years and who underwent patch augmentation of their left atrioventricular valve had a preoperative and postoperative transesophageal echocardiogram with 3-dimensional reconstruction to evaluate the left atrioventricular valve. The indication for operation was left atrioventricular valve regurgitation in 3 patients and left ventricular outflow tract obstruction in 2 patients. Three were rerepairs, and 2 were primary repairs. Both 3-dimensional morphology and color Doppler data were obtained. Two- and 3-dimensional findings were correlated with surgical observations through the use of direct inspection and video images obtained with a head-mounted super-VHS camera.

RESULTS

In each case there was precise correlation between the 3-dimensional and surgical findings as to the cause of leaflet failure in those with regurgitation. The site that would require leaflet augmentation could be determined by means of 3-dimensional echocardiography. Three-dimensional echocardiography provided more specific detail as to the morphology and function of the left atrioventricular valve than did its 2-dimensional counterpart.

CONCLUSIONS

Three-dimensional echocardiography provides detailed information about the status of the left atrioventricular valve in the atrioventricular septal defect and can aid in the planning of either primary or secondary repair.

Repair of complete atrioventricular septal defects in patients weighing less than 5 kg

BACKGROUND

The aim of this study was to evaluate the impact of weight less than 5 kg at operation on mortality and morbidity in patients with atrioventricular septal defect (AVSDc) undergoing total correction.

METHODS

Between January 1990 and December 2002, 190 consecutive patients with AVSDc underwent total biventricular correction. They were divided into two groups: group I (n = 64 patients weighing < 5 kg) and group II (n = 126 patients weighing > 5 kg). Associated major cardiac malformations were found in 49 (25.8%) patients. Associated left atrioventricular valve (LAVV) malformations were found in 35 (18.4%) patients. The mean follow-up time was 4.1 +/- 2.9 years (range 2 months-10.7 years).

RESULTS

The in-hospital mortality in group I was 7.8% (5 patients) versus 8.7% (11 patients) in group II (p = 0.95). Major associated cardiac malformations (p < 0.001) and pulmonary hypertension (p = 0.006) were found to be strong predictors for poor postoperative survival. At discharge the mean LAVVR grade in group I was 1.45 +/- 1.2 versus 1.2 +/- 1 in group II (p = 0.13). The actuarial overall survival rates at 1, 3, 5, and 7 years were 96.5%, 92.5%, 91.5%, and 89% respectively and the actuarial overall reoperation free survival rates at 1, 3, 5, and 7 years were 95%, 87%, 84%, and 73%. Twenty-three patients underwent reoperation due to severe left atrioventricular valve regurgitation (LAVVR). Strong predictors for overall reoperation free survival were the operation year before 1995 (p < 0.001), postoperative LAVVR greater than or equal to 2 (p = 0.006), major associated cardiac malformations (p = 0.00034), associated LAVV malformations (p = 0.0044), and non or partial LAVV cleft closure (p = 0.012). The actuarial survival rates between patients weighing less than 5 kg versus patients weighing more than 5 kg were similar (p = 0.51); instead the overall reoperation free survival was significantly lower in patients weighing less than 5 kg (p = 0.022) according to the log-rank test. Weight less than 5 kg (p = 0.023, beta = -0.6) was one of the predictors for reoperation due to severe LAVVR in this series.

CONCLUSIONS

We may conclude that in the current era repair of AVSDc can be carried out successfully in patients less than 5 kg, however, weight less than 5 kg at initial complete repair seems to be a predictor for late reoperation due to LAVVR. Suture separation at the cleft site or between the leaflets of the newly created mitral valve and the patch remain the main causes of postoperative LAVVR in patients weighing less than 5 kg.

Mitral valve replacement in children: predictors of long-term outcome

BACKGROUND

Mitral valve replacement (MVR) in children has been associated with a high complication rate. We sought to assess predictors of outcomes in children undergoing MVR.

METHODS

A retrospective review of clinical, surgical, and echocardiographic records of patients undergoing MVR was performed. Between 1982 and 2000, 53 children underwent 76 MVR procedures at a median age of 5 years (range, 1 day to 18 years) and weight of 17 kg (range, 3 to 121 kg). Eighteen patients (34%) had more than one MVR. Previous cardiac surgery had been performed in 39 (74%), with 27 (51%) undergoing previous mitral repair. Patients were followed for 9.2 +/- 4.8 (range, 2 to 20) years.

RESULTS

There were 14 patient deaths, with 6 patients dying within 30 days, and five transplants (36%). Ten-year freedom from reoperation was 66%. Long-term survivors were older at initial repair (7.0 vs 2.5 years, p = 0.02), with a lower incidence of residual cardiac lesions (3% vs 37%, p < 0.001) and a lower incidence of surgical procedures at the time of MVR (31% vs 63%, p = 0.04). Survivors had better left ventricular function preoperatively (ejection fraction, 68% vs 54%; p = 0.001) and placement of a prosthetic valve within 1 z-score of the echocardiographically measured mitral valve annulus (p = 0.02).

CONCLUSIONS

Adverse outcome after MVR is common, particularly in the young child undergoing palliative surgery or requiring additional surgical procedures. Preoperative assessment of mitral valve size and ventricular function is essential for risk stratification of these patients.

Simplified technique for patch augmentation and chorda reconstruction of left atrioventricular valve in complete atrioventricular septal defect

Management of the left AV valve is the most crucial component of the repair of complete atrioventricular septal defect (cAVSD). A scarcity or deficiency of leaflet tissue may compromise satisfactory repair in a small number of patients with cAVSD, especially in patients with a normal karyotype. We describe the case of a 44-day-old baby who had cAVSD with severe left atrioventricular valve regurgitation due to dysplastic bridging leaflets. The repair was successfully performed by augmenting leaflet tissue and reconstructing the chorda using single patch. This technique could be one of the options in the repair of valves in order to avoid valve replacement in a small infant, although material of patch and reoperation need to be considered.

A modified 'single patch' technique for complete atrioventricular septal defect correction

We propose a modified single-patch technique consisting in plication of the patch on the left side, which then is sutured with the free edge of the left atrioventricular valve. The proposed technique offers all the advantages of the single-patch technique and at the same time provides additional tissue for reconstructing appropriately the left atrioventricular valve in cases with leaflet tissue deficiency such as severely dysplastic valve, double orifice left atrioventricular valve. This modification augments the left atrioventricular valve tissue appropriately to the orifice size, promotes leftward displacement and improved coaptation with the mural leaflet.

Echocardiographic assessment of obstructive lesions in atrioventricular septal defects

OBJECTIVES

We sought to determine the accuracy of transthoracic echocardiography (TTE) in identifying risk factors in patients with an atrioventricular septal defect (AVSD).

BACKGROUND

Atrioventricular septal defect is a common lesion, and many decisions about it are based on echocardiography alone. The identification of associated left-sided inflow and outflow obstructive lesions is important, as they are responsible for mortality and morbidity.

METHODS

Between 1983 to 1998, 549 patients with AVSD underwent repair. The TTE findings were correlated with surgery, angiocardiography, autopsy or postoperative TTE. Papillary muscle measurements were made in those with either a left ventricular outflow tract (LVOT) or left ventricular inflow abnormality and compared with those measurements from control subjects. Measurements of the LVOT were made in patients with an identified LVOT abnormality.

RESULTS

There were 63 missed lesions, decreasing over time. Double-orifice left atrioventricular valve (DOLAVV) and nonobstructive chordae in the LVOT were more often missed. Reoperation was performed to address a missed lesion in 2 of 68 patients. Two of 55 patients died of reasons related to a missed lesion. In 67% of patients, DOLAVV was missed. Abnormal papillary muscle angles were seen with either a LVOT abnormality or DOLAVV. High insertion of the anterolateral papillary muscle was a risk factor for death or residual LVOT obstruction. Abnormal LVOT measurements were found in patients with tunnel obstruction and those with an acquired subaortic ridge.

CONCLUSIONS

Transthoracic echocardiography provides accurate preoperative information on AVSD.