Project description:Despite improved survival, surgical treatment of atrioventricular septal defect (AVSD) remains challenging. The optimal technique for primary left atrioventricular valve (LAVV) repair and prediction of suitability for biventricular approach in unbalanced AVSD are still controversial. We evaluated the ability of our recently developed echocardiographic left atrioventricular valve reduction index (LAVRI) in predicting LAVV reoperation rate and surgical strategy for unbalanced AVSD. Retrospective echocardiographic analysis was available in 352 of 790 patients with AVSD treated in our institution and included modified atrioventricular valve index (mAVVI), ventricular cavity ratio (VCR), and right ventricle/left ventricle (RV/LV) inflow angle. LAVRI estimates LAVV area after complete cleft closure and was analyzed with regard to surgical strategy in primary LAVV repair and unbalanced AVSD. Of the entire cohort, 284/352 (80.68%) patients underwent biventricular repair and 68/352 (19.31%) patients underwent univentricular palliation. LAVV reoperation was performed in 25/284 (8.80%) patients after surgical correction of AVSD. LAVRI was significantly lower in patients requiring LAVV reoperation (1.92 cm2/m2 [IQR 1.31] vs. 2.89 cm2/m2 [IQR 1.37], p = 0.002) and significantly differed between patients receiving complete and no/partial cleft closure (2.89 cm2/m2 [IQR 1.35] vs. 2.07 cm2/m2 [IQR 1.69]; p = 0.002). Of 82 patients diagnosed with unbalanced AVSD, 14 were suitable for biventricular repair (17.07%). mAVVI, LAVRI, VCR, and RV/LV inflow angle accurately distinguished between balanced and unbalanced AVSD and predicted surgical strategy (all p < 0.001). LAVRI may predict surgical strategy in primary LAVV repair, LAVV reoperation risk, and suitability for biventricular approach in unbalanced AVSD anatomy.
Project description:BackgroundLeft atrioventricular valve regurgitation (LAVVR) after atrioventricular canal (AVC) repair remains a significant cause of morbidity. Papillary muscle arrangement may be important. To investigate the implications of left mural leaflet morphology, we examined anatomic characteristics of the LAVV to determine possible associations with postoperative LAVVR.MethodsAll patients with biventricular AVC repair at our institution between January 1, 2011, and December 31, 2016, with necessary imaging were retrospectively reviewed. We assessed papillary muscle structure and novel measures of the left mural leaflet from preoperative echocardiograms and the degree of LAVVR from the first and last available follow-up echocardiograms. Associations with degree of early and late postoperative LAVVR were assessed with t tests, analysis of variance, or χ2 or Fisher exact tests, and multivariable logistic regression.ResultsThere were 58 of 156 patients (37%) with significant (moderate or severe) early postoperative LAVVR, and 30 of 93 (32%) had significant LAVVR after 6 or more months. Fewer patients with closely spaced or asymmetric papillary muscles had moderate or severe late LAVVR vs those with widely spaced papillary muscles (17% vs 40%, P = .019). Controlling for weight at operation, genetic syndromes, and bypass time, widely spaced papillary muscles increased the odds ratio for late LAVVR to 3.6 (P = .026). Larger mural leaflet area was also associated with late LAVVR on univariable (P = .019) and multivariable (P = .023) analyses. One-third of patients with significant late LAVVR had no significant early postoperative regurgitation.ConclusionsMural leaflet and papillary muscle anatomy are associated with late LAVVR after AVC repair. Late regurgitation can develop in the absence of early LAVVR, suggesting different mechanisms.
Project description:Congenital heart defects affect 60-85% of patients with RASopathies. We analysed the clinical and molecular characteristics of atrioventricular canal defect in patients with mutations affecting genes coding for proteins with role in the RAS/MAPK pathway. Between 2002 and 2011, 101 patients with cardiac defect and a molecularly confirmed RASopathy were collected. Congenital heart defects within the spectrum of complete or partial (including cleft mitral valve) atrioventricular canal defect were diagnosed in 8/101 (8%) patients, including seven with a PTPN11 gene mutation, and one single subject with a RAF1 gene mutation. The only recurrent mutation was the missense PTPN11 c.124 A>G change (T42A) in PTPN11. Partial atrioventricular canal defect was found in six cases, complete in one, cleft mitral valve in one. In four subjects the defect was associated with other cardiac defects, including subvalvular aortic stenosis, mitral valve anomaly, pulmonary valve stenosis and hypertrophic cardiomyopathy. Maternal segregation of PTPN11 and RAF1 gene mutations occurred in two and one patients, respectively. Congenital heart defects in the affected relatives were discordant in the families with PTPN11 mutations, and concordant in that with RAF1 mutation. In conclusion, our data confirm previous reports indicating that atrioventricular canal defect represents a relatively common feature in Noonan syndrome. Among RASopathies, atrioventricular canal defect was observed to occur with higher prevalence among subjects with PTPN11 mutations, even though this association was not significant possibly because of low statistical power. Familial segregation of atrioventricular canal defect should be considered in the genetic counselling of families with RASopathies.
Project description:An unguarded atrioventricular orifice is an extremely rare congenital anomaly characterized by the absence of the atrioventricular valve in varying proportions. While atresia of the mitral or aortic valves are usually described as causes for hypoplastic left heart, our case highlights the role of free atrioventricular valve regurgitation and consequent volume loss of the left heart, giving rise to a small left ventricle. There was an associated double-outlet right ventricle and Type B aortic interruption. While we have attempted to discuss the complex management options in this scenario, the parents decided to withdraw further care.
Project description:Background: Left atrioventricular valve (LAVV) stenosis following an atrioventricular septal defect (AVSD) repair is a rare but potentially life-threatening complication. While echocardiographic quantification of diastolic transvalvular pressure gradients is paramount in the evaluation of a newly corrected valve function, it is hypothesized that these measured gradients are overestimated immediately following a cardiopulmonary bypass (CPB) due to the altered hemodynamics when compared to postoperative valve assessments using awake transthoracic echocardiography (TTE) upon recovery after surgery. Methods: Out of the 72 patients screened for inclusion at a tertiary center, 39 patients undergoing an AVSD repair with both intraoperative transesophageal echocardiograms (TEE, performed immediately after a CPB) and an awake TTE (performed prior to hospital discharge) were retrospectively selected. The mean (MPGs) and peak pressure gradients (PPGs) were quantified using a Doppler echocardiography and other measures of interest were recorded (e.g., a non-invasive surrogate of the cardiac output and index (CI), left ventricular ejection fraction, blood pressures and airway pressures). The variables were analyzed using the paired Student’s t-tests and Spearman’s correlation coefficients. Results: The MPGs were significantly higher in the intraoperative measurements when compared to the awake TTE (3.0 ± 1.2 vs. 2.3 ± 1.1 mmHg; p < 0.01); however, the PPGs did not significantly differ (6.6 ± 2.7 vs. 5.7 ± 2.8 mmHg; p = 0.06). Although the assessed intraoperative heart rates (HRs) were also higher (132 ± 17 vs. 114 ± 21 bpm; p < 0.001), there was no correlation found between the MPG and the HR, or any other parameter of interest, at either time-point. In a further analysis, a moderate to strong correlation was observed in the linear relationship between the CI and the MPG (r = 0.60; p < 0.001). During the in-hospital follow-up period, no patients died or required an intervention due to LAVV stenosis. Conclusions: The Doppler-based quantification of diastolic transvalvular LAVV mean pressure gradients using intraoperative transesophageal echocardiography seems to be prone to overestimation due to altered hemodynamics immediately after an AVSD repair. Thus, the current hemodynamic state should be taken into consideration during the intraoperative interpretation of these gradients.
Project description:BackgroundSurgical and perioperative improvements permit earlier repair of partial and transitional atrioventricular septal defects (AVSD). We sought to describe contemporary outcomes in a multicenter cohort.MethodsWe studied 87 patients undergoing primary biventricular repair of partial or transitional AVSD between June 2004 and February 2006 across seven North American centers. One-month and 6-month postoperative data included weight-for-age z-scores, left atrioventricular valve regurgitation (LAVVR) grade, residual shunts, and left ventricular ejection fraction. Paired methods were used to assess 6-month change.ResultsMedian age at surgery was 1.8 years; median weight z-score was -0.88. Median days for ventilation were 1, intensive care 2, and hospitalization 5, all independent of age, with 1 in-hospital death. At 1 month, 27% (16 of 73) had ejection fraction less than 55%; 20% (17 of 87) had significant LAVVR; 2 had residual shunts; 1 each had subaortic stenosis and LAVV stenosis. At 6 months (n = 60), there were no interim deaths, reinterventions, or new development of subaortic or LAVV stenosis. Weight z-score improved by a median 0.4 units (p < 0.001), especially for underweight children less than 18 months old. Left atrioventricular valve regurgitation occurred in 31% (change from baseline, p = 0.13), occurring more frequently in patients repaired at 4 to 7 years (p = 0.01). Three patients had ejection fraction less than 55%, and 1 had a residual atrial shunt.ConclusionsSurgical repair for partial/transitional AVSD is associated with low morbidity and mortality, short hospital stays, and catch-up growth, particularly in underweight children repaired between 3 and 18 months of age. Left atrioventricular valve regurgitation remains the most common residual defect, occurring more frequently in children repaired after 4 years of age.