Pulmonary artery augmentation using decellularized equine pericardium (Matrix Patch™): initial single-centre experience

OBJECTIVES

The aim of this study was to report our initial experience when using Matrix Patch™ a cell-free equine-derived pericardium for the augmentation of branch pulmonary arteries (PAs) in children.

METHODS

Between September 2016 and September 2019, Matrix Patch was used for the augmentation of branch PAs in 96 patients and implanted in 147 separate locations. The median age at implantation was 3.2 years (interquartile range: 0.9-8.4), and 33% of patients were infants. The patch was used mainly in redo surgeries (89.6%). Intra-procedural feasibility and reinterventions were analysed. Primary end points were death or patch-related reoperation/stent implantation. Explanted patches were stained for recellularization/calcification, or to reveal proliferation/inflammation.

RESULTS

A total of 81 patients, who received patches in 119 separate locations, were followed within a median of 20 months (interquartile range: 10.2-30.2). Patients with early reoperation/stent implantation were excluded from follow-up. No patch-related death was noted. Survival at last follow-up was 88% (95% CI: 78.8-93.7%). Overall probability of freedom from reoperation/stent implantation per location, 12 and 24 months after initial surgery was 85.8% (95% CI: 76.2-91.7%) and 78.7 (95% CI: 65.9-87.2%), respectively. At 20 months, superficial proliferation with discrete macrophage activity was seen in explants; however, no signs of calcification are observed.

CONCLUSIONS

The initial experience with the Matrix Patch in PAs showed comparable results to other xenogeneic patch materials. Long-term follow-up data are needed to prove the desired durability of the patch in different locations.

Subcoronary Ross/Ross-Konno operation in children and young adults: initial single-centre experience

OBJECTIVES

We sought to evaluate the outcome after modified subcoronary Ross/Ross-Konno operation in children and young adults.

METHODS

Between January 2013 and January 2019, a total of 50 patients with median age of 6.3 years (range 0.02-36.5 years, 58% males), including 10 infants (20%), received modified subcoronary Ross/Ross-Konno operation at our institution. Survival, morbidity, reinterventions, aortic valve function and aortic root dimensions were analysed.

RESULTS

At a median follow-up of 31.2 months (range 14.4-51 months), there were 1 early death and 1 late death, both in the infant group. The overall survival at 5 years after the operation was 95%. Two patients needed aortic valve replacement, 11 and 15 months after their Ross operation. At 5 years, freedoms from reoperation on the autograft and on the right ventricle to pulmonary artery conduit were 94% and 97%, respectively. Freedom from aortic valve regurgitation greater than mild was 97% at 5 years. Median dimensions of the aortic root at all levels remained in normal range at last visit. Forty-four patients (95%) were in New York Heart Association class I with normal left ventricular function.

CONCLUSIONS

The initial experience with the subcoronary Ross/Ross-Konno operation in children and young adults showed excellent outcome. The mortality and morbidity among infants remain significant. The described technique is reproducible and might be advantageous in situations when prosthetic supporting techniques interfere with somatic growth.

Modified Ross-Konno procedure in children: subcoronary implantation technique with Konno incision for annular and subannular hypoplasia

OBJECTIVES

The technique of subcoronary autograft implantation for the Ross procedure has shown excellent durability of aortic valve function in adults. However, its use in children with hypoplastic aortic annulus or multilevel left ventricular outflow tract obstruction (LVOTO) was traditionally precluded. We combined this technique with a Konno incision and evaluated LVOTO relief and durability of the autograft function in growing patients.

METHODS

Between January 2012 and January 2017, 13 patients with severe LVOTO and hypoplastic aortic annulus underwent Ross-Konno procedure with subcoronary autograft implantation. The median age at operation was 14 months. Six were infants. Concomitant procedures included resection of endocardial fibroelastosis (n = 9), mitral valvuloplasty (n = 2) and aortic arch repair (n = 1). The Konno incision was enlarged with a patch. The autograft was implanted beneath the ostia of the coronary arteries, retaining external support by the native aortic annulus.

RESULTS

A newborn with hypoplastic left heart complex and Turner syndrome died in hospital: early mortality of 7.7%. No residual LVOTO or autograft regurgitation was observed at discharge. At a median follow-up of 20 months, no death had occurred. No catheter or surgical reintervention on the aortic valve or any LVOT site was needed. All peak pressure gradients across the LVOT were <10 mmHg. No autograft regurgitation was detected.

CONCLUSIONS

The Ross procedure using subcoronary implantation technique combined with LVOT Konno enlargement is feasible even in patients with multilevel LVOTO and marked size discrepancy between the autograft and native aortic annulus. Longer follow-up is indicated to confirm the expected durability of the autograft function.

Kristallstrukturen von (n-Bu4N)[B6Cl6], (n-Bu4N)[B6Br6] und (Ph3P=N=PPh3)[B6I6] sowie Schwingungsspektren und Normalkoordinatenanalyse der Hexahalogeno-c/osö-Hexaboratradikalanionen [B6X6]-, X = Cl, Br, I / Crystal Structures of (n-Bu4N)[B6Cl6], (n-Bu4N)[B6Br6], and (Ph3P=N=PPh3)[B6I6], and Vibrational Spectra and Normal Coordinate Analysis of the Hexahalogeno-closo-hexaborate Radical Anions [B6X6]- , X = Cl, Br, I

Oxidation of hexahalogeno-closo-hexaborates [B6X6]2-, X = Cl, Br, I, with (NH4)2[Ce(NO3)6] in ethanol yields coloured radical ions [B6X6]-. X-ray structure determina­ tions have been performed on single crystals of (n-Bu4N)[B6Cl6] (1) (monoclinic, space group P21/c,a = 13.144(2),6 = 12.594(2),c = 17.688(5) Å, β = 107.29(2)°,Z=4),(n-Bu4N)[B6Br6] (2) (monoclinic, space group P21/c, a = 13.529(5), b = 13.096(5), c = 17.863(5) Å, β = 107.20(5)°, Z = 4) and (Ph3P=N=PPh3)[B6I6] (3) (triclinic, space group P1̄, a = 9.3137(8), b = 10.6988(10), c = 11.8760 Å , a = 102.220(7), β = 99.34J(8), 7 = 96.030(7)°, Z = 1). The average B-B distances are nearly equal (1.733 Å (1), 1.728 Å (2), 1.728 Å (3)) while the B-X distances increase (1.762 Å (1), 1.912 Å (2), 2.120 Å (3)). Using the molecular parameters, normal coordinate analyses have been performed and a good agreement of observed and calculated frequencies of 10B and 11B labelled derivatives has been achieved. The valence force constants fd(BB) and fd(BX) of [B6X6]- are 1.17 and 4.17 (X = Cl), 1.18 and 3.34 (Br) and 1.18 and 2.60 mdyn/Å (I), respectively.

Schwingungsspektren und Normalkoordinatenanalyse der Tetrahalogeno-closo-1,2-diphosphahexaborane P2B4X4, X = Cl, Br / Vibrational Spectra and Normal Coordinate Analysis of the Tetrahalogeno-closo-1,2-diphosphahexaboranes P2B4X4, X = Cl, Br

High resolution vibrational spectra of the tetrahalogeno-closo-1,2-diphosphahexaboranes P2B4X4, X = Cl, Br have been measured at low temperatures (20 - 60 K). The boron-halogen stretching vibrations are observed below 370 cm-1 while the P-P valence vibrations are found at 414 (Cl) and 372 cm-1 (Br). Due to the presence of the boron isotopes 10B and 11B the P-P stretching vibrations and the cage modes in the region of 550 to 1200 cm-1 are split. Based on the crystallographic data of P2B4C14 normal coordinate analyses have been performed. Using a set of 16 force constants (e.g. fd(PP) = 1.35 (X = Cl) and 1.20 (Br), fd(BB) = 1.30 / 1.65 (Cl) and 1.45 /1.60 (Br), fd(BX) = 4.40 (Cl) and 3.53 (Br) mdyn / Å) a good agreement of observed and calculated frequencies has been achieved.

Complications and risk factors in 2731 diagnostic mini-laparoscopies in patients with liver disease

BACKGROUND/AIMS

Mini-laparoscopy (ML) allows macroscopic assessment and biopsy under direct vision and therefore is a valuable technique in the diagnosis of liver disease. Herein we report procedure-related complications and risk factors.

METHODS

A total of 2731 consecutive patients underwent diagnostic ML at two university hospitals (June 1996-December 2007). ML was performed using standard technique with a 1.9mm optical instrument. Coagulation of the liver biopsy site was performed with APC. The following variables were analysed as risk factors for complications: platelet count (<50/nL), international normalized ratio (INR) (>1.5), Cirrhosis, signs of portal hypertension, prior abdominal surgery.

RESULTS

Major complications occurred in 1.0% (n=27) of patients and these were, delayed bleeding from the liver biopsy site or abdominal wall (in 0.7% of patients) and intestinal perforation (in 0.3% of patients). Two patients died after severe haemorrhage (mortality 0.07%); the other patients recovered without sequelae. Bleeding risk was increased in patients with low platelets (OR=6.1), increased INR (OR=8.9), cirrhosis (OR=1.9) and portal hypertension (OR=2.1). Logistic regression showed a significant correlation only for the concurrence of low platelets and increased INR (P = 0.001; OR=14.1); bootstrap analysis identified INR >1.5 as significant predictor (P = 0.0002). Prior abdominal surgery did not carry a significant risk for intestinal perforation (OR=1.1; P = 0.142), unless abdominal adhesions were present (OR=9.5; P = 0.0002). None of the patients required surgery for intestinal perforation.

CONCLUSION

Mini-laparoscopy is a diagnostic technique with a low complication rate. However, in patients with increased INR, low platelets or after extensive abdominal surgery, complications may occur in up to 5%.

A simple clinical model to estimate the probability of Marfan syndrome

BACKGROUND

Marfan syndrome is a heritable connective tissue disease. Definitive diagnosis is complex, and requires sequencing of a large gene, FBN1.

AIM

We aimed to develop a simple model to estimate the pre-test probability of Marfan syndrome.

DESIGN

Prospective cross-sectional study.

METHODS

We applied diagnostic standards for definitive diagnosis or exclusion of Marfan syndrome in 329 consecutive persons. In 208 persons with random assignment to our derivation group, we performed multivariate logistic regression to assess 14 clinical variables for inclusion in a prediction model with derivation of score points from the estimated coefficients. We created cut-offs to classify low, moderate and high probability of Marfan syndrome. For validation, we applied the model to the remaining 121 persons.

RESULTS

We identified seven variables for inclusion in the final model, where we assigned four score points to ectopia lentis, two points to a family history of Marfan syndrome, and one point to previous thoracic aortic surgery, to pectus excavatum, to a wrist and thumb sign, to previous pneumothorax, and to skin striae. In the derivation group 12, 42 and 92% of persons with low (≤1 point), moderate (>1-3.5 points) or high pre-test probability (>3.5 points) had Marfan syndrome, compared to 12, 57 and 91%, respectively, in the validation group. Positive likelihood ratios were 13.96 and 8.54 in the high probability group of the derivation and validation group, respectively.

CONCLUSION

A simple prediction model provides evidence for Marfan syndrome. This model can be used to identify patients who require definitive diagnostic work-up.