The repair of a type Ia endoleak following thoracic endovascular aortic repair using a stented elephant trunk procedure

BACKGROUND

Type Ia endoleaks are not uncommon complications that occur after thoracic endovascular aortic repair (TEVAR). Because aortic arch vessels prevent extension of the landing zone, it is very difficult to manipulate a type Ia endoleak using an extension cuff or stent-graft, especially when the aortic arch is involved. Here, we retrospectively review our experience of surgical treatment of type Ia endoleak after TEVAR using a stented elephant trunk procedure.

METHODS

From July 2010 to August 2016, we treated 17 patients diagnosed with a type Ia endoleak following TEVAR using stented elephant trunk procedure. The mean age of our patients was 52 ± 8 years. The mean interval between TEVAR and the open surgical repair was 38 ± 43 months.

RESULTS

All cases of type Ia endoleak (100%) were repaired successfully. There were no in-hospital deaths. One case required reintubation and continuous renal replacement therapy due to renal failure; this patient recovered smoothly before discharge. One other patient suffered a stroke and renal failure and did not fully recover following discharge, or follow-up. During follow-up, there were 3 deaths.

CONCLUSIONS

Acceptable results were obtained using a stented elephant trunk procedure in patients with a type Ia endoleak after TEVAR. This technique allowed us to repair the proximal aortic arch lesions, surgically correct the type Ia endoleak, and promote false lumen thrombosis in the distal aorta. Implantation of a stented elephant trunk, with or without a concomitant aortic arch procedure, is an alternative approach for this type of lesion.

Disruption of mechanical stress in extracellular matrix is related to Stanford type A aortic dissection through down-regulation of Yes-associated protein

In this study, we assessed whether the down-regulation of Yes-associated protein (YAP) is involved in the pathogenesis of extracellular matrix (ECM) mechanical stress-induced Stanford type A aortic dissection (STAAD). Human aortic samples were obtained from heart transplantation donors as normal controls and from STAAD patients undergoing surgical replacement of the ascending aorta. Decreased maximum aortic wall velocity, ECM disorders, increased VSMC apoptosis, and YAP down-regulation were identified in STAAD samples. In a mouse model of STAAD, YAP was down-regulated over time during the development of ECM damage, and increased VSMC apoptosis was also observed. YAP knockdown induced VSMC apoptosis under static conditions in vitro, and the change in mechanical stress induced YAP down-regulation and VSMC apoptosis. This study provides evidence that YAP down-regulation caused by the disruption of mechanical stress is associated with the development of STAAD via the induction of apoptosis in aortic VSMCs. As STAAD is among the most elusive and life-threatening vascular diseases, better understanding of the molecular pathogenesis of STAAD is critical to improve clinical outcome.

Dynamic hip system blade versus cannulated compression screw for the treatment of femoral neck fractures: A retrospective study

OBJECTIVE

The aim of this study was to compare clinical outcomes of patients with femoral neck fractures treated with the dynamic hip system blade (DHS-BLADE) or cannulated compression screws.

METHODS

Eighty-six patients with femoral neck fractures were treated by closed reduction internal fixation with a DHS-BLADE (n = 42; 18 males and 24 females; mean age: 56.3 years (37-87)) or cannulated compression screws (n = 44; 20 males and 24 females; mean age: 53.8 years (26-83)) between March 2011 and August 2013. The groups were compared with Harris hip score, operation time, surgical blood loss, incision size, hospital stay, and related complications.

RESULTS

The average follow-up time was 27 months (range, 24-36 months). There was no significant difference for the operation time, incision size, hospital stay, and Harris hip score between the groups. Also, no statistically significant differences in the rates of nonunion (4.5% vs. 0) and avascular necrosis of the femoral head (9.1% vs. 7.1%) were observed. However, the screw group experienced significantly less surgical blood loss (32.4 ± 24.7 ml) than the blade group (87.2 ± 46.6 ml; P = 0.041). The incidence of femoral neck shortening above 10 mm in the screw group was significantly higher than that in the blade group (15.9% vs. 2.4%, P = 0.031). The blade group had a significantly lower incidence of screw migration than the screw group (4.8% vs. 22.7%, P = 0.016).

CONCLUSION

The DHS-BLADE and cannulated compression screws might be equally effective in terms of postoperative fracture union. However, the DHS-BLADE has advantages over cannulated compression screws for preventing femoral neck shortening, screw migration, and cut-out.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

[Progress and challenge of Stanford type A aortic dissection in China]

In recent 20 years, the rapid development of acute Stanford type A aortic dissection in China has been mainly due to three aspects: (1) the refined classification of aortic dissection based on Stanford classification, (2) right axillary artery canal and selective cerebral perfusion technology become basic cardiopulmonary bypass strategy for Stanford type A aortic dissection, and (3) total aortic arch replacement and descending aortic stent graft surgery (Sun's surgery) become the standard treatment of Stanford type A aortic dissection. However, there are still many problems in the diagnosis and treatment of aortic dissection in China, such as: (1) unstandardized, lack of comprehensive guidelines of aortic dissection, (2) immature, perioperative organ protection and intraoperative blood protection technology remains a big flaw, and (3) it takes a long time to get patient prepared for surgery. In conclusion, as to the issue of the management of acute Stanford type A aortic dissection, there will be a long way for Chinese doctors to go. Peers should pay more attention to this problem and take more efforts, so that the outcome of acute Stanford type A aortic dissection surgical patients can be improved.

[Experience of Sun's procedure for chronic type B dissection with aortic arch involvement]

Objective: To study the surgical treatment of chronic type B dissection with aortic arch involvement using Sun's procedure. Methods: Between February 2009 and December 2015, 29 patients [20 males, 9 females, with a mean age of (41±12) years, range 24-64 years] with type B dissection with aortic arch involvement underwent Sun's procedure. Sixteen patient had a history of hypertension. Marfan syndrome was observed in 9 cases, coronary artery disease in 3 cases, mitral regurgitation in 3 patients, cerebrovascular disease in one patient. Twenty-two patients suffered proximal aortic arch disease, 4 cases experienced history of aortic root procedure and 2 subjects had history of pregnancy. Four patients had aortic arch malformation. Results: One case suffered from massive cerebral infarction after surgery and died in another hospital. Concomitant procedures included mitral valve replacement in 3 cases, coronary artery bypass grafting in 3 patients, reconstruction of the right aberrant subclavian artery in one patient. Ventilator support exceeding 24 hours obseved in 2 patients. One of them recieved continuous renal replacement therapy and recovered before discharge. Spinal cord injury was obseved in one case, brain infarction in one patient and pericardial drainage in one case. Two patients required tracheotomy. During 12-94 (43±23) months' follow-up, thoracoabdominal aortic replacment was performed in 4 patients, thoracic endovascular aortic repair (TEVAR) in 2 subjects and repair of perivalvular leakage in one patient. Conclusions: Sun's procedure obtained satisfactory results in patients with chronic type B dissection with aortic arch involvement. Concomitant repair of proximal aortic arch lesions and distal type B dissection can be adopted using Sun's procedure.

In vitro and in vivo evaluation of a small-caliber coaxial electrospun vascular graft loaded with heparin and VEGF

INTRODUCTION

To date, clinically available expanded polytetrafluoro-ethylene (ePTFE) vascular grafts are suboptimal for reconstructing small caliber (D < 6 mm) arteries, owing to thrombosis in early and restenosis in late stage. Our aim in this preliminary study was to fabricate a nano-fibrous vascular graft which was biofunctionalized with VEGF₁₆₅ and heparin. The short term performance was evaluated both in vitro and in vivo.

METHOD

Four-mm caliber grafts were prepared by the coaxial-elctrospun technique, which consisted of poly(l-lactide-co-caprolactone) [P(LLA-CL)] collagen and elastin. Heparin and endothelial cell growth factor-165 (VEGF₁₆₅) were encapsulated in the core of the fibrous. Controlled release of the heparin and VEGF₁₆₅ were evaluated for 28 days. Endothelial cells were cultured on the electrospun grafts or ePTFE grafts as controls. The cellular adhesion, proliferation and morphology were examined. Electrospun or ePTFE grafts were randomly implanted into a rabbit infrarenal aortic replacement model (n = 30) for 28 days without any antiplatelet therapy. At the termination, all grafts were examined by Doppler ultrasound and then evaluated with histology and scanning electron microscopy.

RESULTS

The cumulative release amount of heparin (6.93 ± 1.03 mg) and VEGF₁₆₅ (22.17 ± 5.56 μg) during 28 days were measured. Endothelial cells cultured on electrospun grafts showed significantly higher attachment efficiency and proliferation compared to the ePTFE ones (P < 0.001). At 2 h more ECs had attached to the P(LLA-CL)/Collagen/Elatin grafts (83.26 ± 8.02%) compared to P(LLA-CL) (67.07 ± 4.16%) and ePTFE (46.87 ± 8.85%). ECs proliferated faster on VEGF loaded grafts (O.D = 2.9 ± 1.2, n = 12) compared to ePTFE (O.D = 1.7 ± 1.0, n = 12). The patency was significantly higher in electrospun grafts (86.6%) than ePTFE grafts (40.0%) (P = 0.021). Correspondingly, the microscope images of electrospun implants showed little thrombus when compared with the ePTFE implants.

CONCLUSION

Biofunctionalized electrospun graft showed surgical properties, hemocompatibility and higher short-term patency compared with the ePTFE grafts. Despite good early performances, profound study should be designed for long-term evaluation.

Treatment of patients with aortic disease during pregnancy and after delivery

Objective

This study aimed to review treatment of patients with aortic disease during pregnancy and after delivery in Beijing Anzhen Hospital.

Methods

A retrospective study was conducted using data from 12 patients with aortic disease during pregnancy and after delivery in our institution from May 2005 to December 2014. Patients were provided different treatments based on the type of aortic disease and clinical characteristics.

Results

The mean age was 29.83 ± 4.17 years, mean height was 171.7 ± 8.22 cm, mean weight was 68.55 ± 10.62 kg, and mean body mass index was 23.18 ± 2.93 kg/m². Two patients with Stanford type A aortic dissection died of renal failure after surgery. All of the other patients were discharged. Six foetuses survived. One patient continued her pregnancy after an aortic operation. The gestational age of the remaining five patients was less than 28 weeks at the time of the operation and all foetuses of these five patients died.

Conclusions

A suitable treatment strategy for aortic disease during pregnancy and after delivery should be chosen based on an individual’s comprehensive clinical condition. Foetal management should be chosen based on gestational age and severity of aortic disease.

[Reoperation for residual aneurysm of coronary anastomosis after Bentall procedure]

Objective: To introduce a new operative method for residual aneurysm of coronary anastomosis after Bentall procedure. Methods: Between March 2011 and December 2012, six patients in Beijing Anzhen Hospital with residual aneurysm of coronary anastomosis (CT showed goldfish eye sign at the openings of coronary) after Bentall procedure underwent the operation of concentric circular patch procedure under cardiopulmonary bypass. Femoral artery, right atrium and upper right pulmonary artery cannulation were used for cardiopulmonary bypass, and the artificial vessel was transected after cardiac arrest. A concentric circular patch was pruned, whose outside diameter was slightly larger than the aneurysm and the inside diameter was equal to the openings of coronary. The outer edge of the patch was anastomosed to the outer edge of the aneurysm (opening of artificial vessel in primary surgery) with 4-0 prolene. The inner edge of the patch was anastomosed to the openings of coronary with 5-0 prolene. Results: All patients had clinical recovery. Postoperative CT demonstrated the disappearance of residual aneurysm during follow-up (the goldfish eye sign disappeared). Conclusion: The concentric circular patch procedure is a feasible treatment for residual aneurysm of coronary anastomosis.

[Surgical treatment of aortic dissection with lower extremity ischemia]

Objective: To explore the clinical outcome of the surgical treatment for aortic dissection with lower extremity ischemia. Methods: Between March 2009 and April 2013, 14 patients with type A aortic dissection and lower extremity ischemia underwent Sun's procedure in Beijing Anzhen Hospital. Ascending aorta-iliac artery bypass, ascending aorta-femoral artery bypass, femoral-femoral artery bypass and axillary -femoral artery bypass were performed on some severe patients at the same time. Results: Two death occurred, and the others were improved or recovered from symptoms. Follow-up was complete with an average time of 24 months and no aortic relevant complications occurred. Conclusion: As for patients with type A aortic dissection and lower extremity ischemia, simultaneous radical femoral artery bypass procedure is effective in improving their survival rate and quality of life.

Risk factors for continuous renal replacement therapy after surgical repair of type A aortic dissection

BACKGROUND

To identify the risk factors for continuous renal replacement therapy (CRRT) following surgical repair of type A aortic dissection (TAAD) using the total arch replacement and frozen elephant trunk (TAR + FET) technique.

METHODS

The study included 330 patients with TAAD repaired using TAR + FET between January 2014 and April 2015. Mean age was 47.1±10.2 years (range, 18-73 years) and 242 were male (73.3%). Univariate and multivariate analyses were used to identify the risk factors for CRRT.

RESULTS

Postoperative CRRT was required in 38 patients (mean age 50.7±10.0 years; 27 males). Operative death occurred in 12 patients (3.6%, 12/330). The mortality rate was 23.7% (9/38) in patients with CRRT and 1.0% (3/292) in those without CRRT (P<0.001). Factors associated with CRRT were age (50.7±10.0 vs. 46.7±10.2 years, P=0.023), preoperative serum creatinine (sCr) (135.0±154.2 vs. 85.7±37.0 µmol/L, P<0.001), emergency operation (89.5% vs. 73.3%, P=0.030), cardiopulmonary bypass (CPB) time (265.2±98.8 vs. 199.7±44.2 minutes, P<0.001), cross-clamp time (144.6±54.8 vs. 116.3±33.2 minutes, P<0.001), the amount of red blood cell (8.0±5.2 vs. 3.7±3.3 unit, P<0.001) and fresh frozen plasma (507.8±350.3 vs. 784.2±488.5 mL, P<0.001) transfused intraoperatively, preoperative D-dimmer level (11,361.0 vs. 2,856.7 mg/L, P<0.001) and reexploration for bleeding (15.8% vs. 2.4%, P<0.001). In multivariate analysis, risk factors for CRRT were CPB time (minute) [odds ratio (OR) 1.018; 95% confidence interval (CI), 1.007-1.029; P=0.002], preoperative sCr level (µmol/L) (OR, 1.008; 95% CI, 1.000-1.015; P=0.040), and the amount of red blood cell transfused intraoperatively (unit) (OR, 1.206; 95% CI, 1.077-1.350; P<0.001).

CONCLUSIONS

In this series of patients with TAAD, the time of CPB (minute), sCr level (µmol/L) and the amount of red blood cell transfused intraoperatively (unit) were risk factors for CRRT after TAR + FET.

Endovascular repair of residual intimal tear or distal new entry after frozen elephant trunk for type A aortic dissection

BACKGROUND

In patients with type A dissection, residual dissection and new distal entry tears following the frozen elephant trunk (FET) procedure adversely affect long-term prognosis. Management include open and endovascular repair, while clinical experience is limited. We evaluate the efficacy of thoracic endovascular aortic repair (TEVAR) in management of residual intimal tear or distal new entry tear following FET in patients with type A aortic dissection (TAAD).

METHODS

Between May 2003 and April 2013, we performed FET and total arch replacement for 1,003 patients with TAAD. Among these, 23 patients (2.3%) required TEVAR for distal new entry (n=2) or residual intimal tear (n=21) at a mean of 2.0±1.6 years after FET. Mean age was 50.1±11.5 years. Marfan syndrome was seen in 2 patients (8.7%).

RESULTS

Procedural success was 100%. The distal landing zone was above the 11th thoracic vertebra (T11) in 86.9% (20/23). Neither death nor any paraplegia or stroke occurred early after TEVAR. Follow-up was complete in 100% averaging 2.8±1.7 years (0.3-6.4). One non-Marfan patient died of distal aortic rupture at 4 months after TEVAR. No late stroke or paraplegia occurred. Survival was 95.7% (95% CI, 72.9-99.4%) at 3 and 5 years, respectively. CTA detected false lumen obliteration by thrombus around the endograft in the descending aorta in 91.3% (21/23) of patients.

CONCLUSIONS

These early and midterm outcomes show the efficacy of TEVAR in obliterating the residual intimal tear or distal new entry after FET in patients with TAAD. TEVAR may be an alternative approach to distal new entry or residual intimal tear following FET for patients with TAAD.

Adjunctive antidepressant use in schizophrenia in China: A national survey (2002-2012)

OBJECTIVE

This study examined the pattern of adjunctive antidepressant use in schizophrenia patients and its demographic and clinical correlates in a nationwide survey in China.

METHODS

Fourteen thousand and thirteen patients in 45 Chinese psychiatric hospitals or centers were interviewed (4,486 in 2002, 5,288 in 2006, and 4,239 in 2012). Patients' sociodemographic and clinical characteristics were recorded using a standardized protocol and data collection procedure. Chi-square test, independent-samples t test, Mann-Whitney U test, and multiple logistic regression analysis were used in data analyses.

RESULTS

Antidepressant use was found in 5.2% of the study population with 4.6% in 2002, 4.3% in 2006, and 6.9% in 2012, respectively. A significant increase in use from 2006 to 2012 was found (p < .001). Multiple logistic regression analyses in the whole population revealed that patients receiving adjunctive antidepressants were more likely to be outpatients in tertiary referral centers (level-III hospitals) and who had an earlier age of onset, less severe global illness, but more depressive symptoms. They were less likely to receive first-generation antipsychotics but more likely to receive benzodiazepines (R²  = 0.255, p < .001).

CONCLUSIONS

Despite an increasing trend, the frequency of antidepressant use in schizophrenia in China was considerably lower than in Western countries. The benefits and risks associated with concomitant use of antidepressants in schizophrenia need to be studied further.

[Focal segmental glomerulosclerosis after renal transplantation in a child with ANCA-associated glomerulonephritis: case report and literature review]

Objective: To study the clinical features and treatment of focal segmental glomerulosclerosis (FSGS) after renal transplantation in a child with ANCA-associated glomerulonephritis. Method: The clinical and pathological data of the patient treated in the Department of Pediatrics as well as in the Department of Organ Transplantation in November 2015 in the First Affiliated Hospital of Sun Yat-sen University, who was diagnosed with de novo FSGS after renal transplantation with a primary disease ANCA-associated glomerulonephritis, was analyzed retrospectively. Reports on "ANCA-associated glomerulonephritis" "(renal OR kidney) transplantation" "focal segmental glomerular sclerosis" were searched and reviewed. Result: A ten years old female was definitely diagnosed with ANCA-associated glomerulonephritis on the 81^st day after the onset of primary ANCA associated glomerulonephritis. Because of progressive decline of renal function, a hemodialysis period for 7 months was administered following the pulsed methylprednisolone as well as cyclophosphamide treatment. The renal transplantation was then carried out 18 months later, the renal function recovered 7 days later while proteinuria reappeared 28 days after renal transplantation. Based on the anti-rejection treatment, 3 times pulsed methylprednisolone administration did not make difference on reducing the proteinuria and then a renal biopsy was conducted and the transplanted kidney proved to be a newly developed FSGS. Consequently, plasma exchange therapy was administrated. When the plasma exchange course finished, the proteinuria decreased significantly (from 3.270 g/24 h to 0.370 g/24 h). No reports were retrieved either in Chinese databases or at PubMed as well as Medline databases. Conclusion: FSGS appears in transplanted kidney in patient with a primary renal disease as ANCA associated glomerulonephritis with early proteinuria after transplantation as well as negative P-ANCA and MPO. Pathology of renal biopsy revealed FSGS while the pathology of other recipient was not FSGS. The patient had no response to pulsed methylprednisolone therapy. Instead, plasma exchange therapy was an alternative also effective treatment for de novo FSGS in transplanted kidney.

Surgery for mitral regurgitation in patients with aortic root aneurysm: Transaortic or transseptal approach?

OBJECTIVE

Mitral regurgitation is common in patients with aortic root aneurysm. Mitral valve repair (MVP) or replacement (MVR) can be performed for these patients through either a transverse aortotomy (TA) or transseptal approach (TS). This study sought to compare the early outcomes of mitral valve surgery through the TA and TS approaches and decide which is optimal for this subset of patients.

METHODS

Between March 2013 and April 2015, we operated on 99 patients (81 males, 81.8%) with aortic root aneurysm who developed mitral regurgitation. Mean age was 47.8±16.5years. MVR was performed in 66 patients (TAR=27; TSR=39) and MVP in 33 (TAP=8; TSP=25). The baseline and operative outcomes data were compared between patients with MVR and MVP through the TA vs TS approaches.

RESULTS

Preoperatively, the mitral regurgitation area was significantly larger in the MVR than MVP groups (8.9±2.0 vs 7.8±3.8 cm², p=0.0009), and in the TSP vs TAP groups (8.5±4.1 vs 5.6±1.3cm², p=0.0049), but no significant difference was found between the TAR and TSR groups (8.7±2.2 vs 9.0±1.8cm², p=0.4681); the aortic sinus size was significantly larger in the TAR than TSR group (66.7±15.8 vs 52.1±8.8mm, p=0.0061). Subvalvular structure was preserved in 12 MVR patients (18.2%). In MVP patients, Kay annuloplasty was used in 11 (33.3%) and annuloplastic ring in 22 (66.7%). The times of cardiopulmonary bypass (CPB) and cross-clamp in patients with TA approach were significantly shorter compared to those with the TS approach (139±34 vs 176±38min, p=0.0001; 101±26 vs 129±31min, p=0.0002). No cases of mortality, stroke and renal failure occurred in the whole series. The amount of transfusion, lengths of ICU and hospital stay did not differ between patients with MVR and MVP, and between the TA and TS approaches.

CONCLUSIONS

Both the TA and TS approaches achieved good early outcomes in MV surgery for patients with root aneurysm. The transverse aortotomy was associated with shorter CPB and cross-clamp times. Surgical approaches should be selected according to the underlying mitral valve etiology and the size of the aortic root.

Aortic Dissection in Pregnancy: Management Strategy and Outcomes

BACKGROUND

Aortic dissection in pregnancy is a rare but lethal catastrophe. Clinical experiences are limited. We report our experience in 25 patients focusing on etiology, management strategies, and outcomes.

METHODS

Between June 1998 and February 2015, we treated 25 pregnant women (mean age, 31.6 ± 4.7 years) in whom aortic dissection developed at a mean of 28 ± 10 gestational weeks (GWs). Type A aortic dissection (TAAD) was present in 20 (80%) and type B (TBAD) in 5 (20%). Marfan syndrome was seen in 17 (68%). Management strategy was based on dissection type and GWs.

RESULTS

TAADs were managed surgically in 19 (95.0%) and medically in 1 (5.0%). Maternal and fetal mortalities were, respectively, 14.3% (1 of 7) and 0 (0 of 7) in the "delivery first" group (7 of 20), 16.7% (1 of 6) and 33.3% (2 of 6) in "single-stage delivery and aortic repair" group (6 of 20), 16.7% (1 of 6) and 66.7% (4 of 6) in "aortic repair first" group (6 of 20), and 100% (1 of 1) and 100% (1 of 1) in the "medical management" group (1 of 20). TBADs were managed surgically in 60% (3 of 5) and endovascularly and medically in 20% each (1 of 5). No maternal deaths occurred. Fetal mortality was 100% in the surgical group and 0% in the other groups. During late follow-up, which was complete in 95.2% (20 of 21), 3 maternal and 2 fetal deaths occurred in the TAAD group. Overall maternal survival was 68.6% at 5 years.

CONCLUSIONS

Marfan syndrome predominates among women with aortic dissection in pregnancy. For TAADs, after 28 GWs, delivery followed by surgical repair can achieve maternal and fetal survival adequately; before 28 GWs, maternal survival should be prioritized given the high risk of fetal death. For TBADs in pregnancy, nonsurgical management is preferred.

[Clinical features and gene mutation analysis of 13 Chinese juvenile patients with nephronophthisis]

Objective: To explore the clinical features and pathogenic gene mutation of juvenile nephronophthisis (NPHP) in Chinese patients. Method: Clinical data and blood samples of 27 juvenile NPHP patients from 25 families who were initially clinically diagnosed in six hospitals in Guangdong province were collected. NPHP1 homozygous deletions were detected in all patients. Sequencing of NPHP1 gene was performed when homozygous deletions were not found in patients without eye involvement. In patients with eye involvement, NPHP5 sequencing was carried out initially and subsequently NPHP10 gene and NPHP1 when there were no NPHP5 gene mutation found. Result: Diagnosis was confirmed in 13 patients by renal pathology and (or) gene sequencing, including four boys and nine girls with a median onset age of 8.5(0.1-12.8) years. Seven of the 13 patients had a normal routine urine test and six patients had mild to moderate proteinuria. None had persistent hematuria. The estimated glomerular filtration rate of the 13 patients was (12.7±10.7) ml/(min·1.73 m²) at the time of diagnosis. Renal cysts were found in only five patients by iconography. Decreased renal size was observed in nine cases and normal renal size in four patients. Renal pathology was available in five patients, renal cysts formation at the cortical-medullar area, thickening and laying tubular basement membrane, were observed. Two of the thirteen children had eye involvement, one had liver impairment and one had growth retardation. NPHP1 gene defects were detected in seven patients with a mutation rate of 25.9%, and large homozygous deletions were observed in three patients. Four patients had single point mutations, i. e. compound heterozygous mutations (c.13 C>T and c. 1520+ 5 G>A) in one patient; homozygous mutation in three patients, two patients were siblings from the same pedigree harbored c. 1756 C>T and the other one harbored c. 1298delA. NPHP5 gene homozygous mutation was found in one pedigree. The fourteen children without renal pathology and whose genetic tests were negative shared similar clinical features with the thirteen patients whose diagnosis were confirmed by gene mutation and (or) renal pathology. Conclusion: The onset of juvenile NPHP is insidious. Urine and renal iconography changes are mild or negative. The ratio of NPHP1 mutant patient is similar with previous reports, but the proportion of NPHP1 gene homozygous deletions is much lower and all of the NPHP1 gene single point mutations detected in this research were novel, which indicates a genetic discrepancy existed between Chinese NPHP patients and the western ones.

Two Dimensional Antiferromagnetic Chern Insulator: NiRuCl6

Density functional theory (DFT) and Berry curvature calculations show that quantum anomalous Hall effect (QAHE) can be realized in two-dimensional(2D) antiferromagnetic (AFM) NiRuCl₆. The results indicate that NiRuCl₆ behaves as an AFM Chern insulator and its spin-polarized electronic structure and strong spin-orbit coupling (SOC) are responsible for the QAHE. By tuning SOC, we found that the topological property of NiRuCl₆ arises from its energy band inversion. Considering the compatibility between the AFM and insulators, AFM Chern insulator provides a new way to archive high temperature QAHE in experiments due to its different magnetic coupling mechanism from that of ferromagnetic (FM) Chern insulator.

Correction of Traumatic Tricuspid Insufficiency Using the Double Orifice Technique

Traumatic tricuspid insufficiency is an uncommon clinical condition and surgical procedures vary. In this paper we report our experience in treating traumatic tricuspid insufficiency using the double orifice technique. From January 2000 to September 2003, 10 patients with traumatic tricuspid regurgitation were admitted to our hospital, 5 of whom were corrected using the double orifice technique. There were 4 males and 1 female with ages ranging from 31 to 52 years. Preoperative transthoracic echocardiography (TTE) detected severe tricuspid regurgitation in 4 patients and moderate tricuspid regurgitation in 1 patient. At surgery, tear of the tricuspid anterior papillary muscle was found in 2 cases and anterior chordal rupture in 3 cases. The valves were successfully repaired using the double orifice technique in combination with ring annuloplasty. There was no repeat operation, no operative complications or deaths. Before discharge, TTE detected normal tricuspid valve function in 2 cases and tiny regurgitation in 3 cases. After a follow up of 8 to 36 months, TTE demonstrated normal valve function in 1 patient and tiny regurgitation in 4 patients. The double orifice technique appears to be a simple but effective method of repairing traumatic tricuspid incompetence. Satisfactory clinical outcomes can be produced in carefully selected patients.

Minimal Access Heart Surgery via Lower Ministernotomy: Experience in 460 Cases

Minimally invasive cardiac surgery has captured the interest and attention of cardiac surgeons throughout the world. We reviewed our experience of minimal access cardiac operations performed through a lower median ministernotomy. Between January 1997 and August 2003, 100 congenital, 178 valvular, 168 coronary, 12 aneurysmal, and 2 other operations were performed via a 6 to 9 cm lower ministernotomy in 460 consecutive patients. No special instruments were required. Four patients died, and 2 re-operations were necessary. Complications occurred in 28 patients (6.1%). The mean cardiopulmonary bypass time was 88.50 ± 65.16 min, crossclamp time was 55.81 ± 31.89 min, time to extubation was 14.71 ± 29.33 h, and total chest drainage was 7.28 ± 5.07 mL·kg−1. Blood transfusions of 951.42 ± 642.34 mL were needed in 282 patients. Postoperative hospital stay was 11.6 ± 6.0 days. Our experience shows that many types of cardiac operations can be performed through a lower ministernotomy. This technique results in less trauma, quick recovery, and reduces the risk of infection and blood loss. It is a safe and easy procedure that can bring about favorable early outcomes in a wide range of cardiac operations.

Moderate hypothermic circulatory arrest in total arch repair for acute type A aortic dissection: clinical safety and efficacy

BACKGROUND

Continued debates exist regarding the optimal temperature during hypothermic circulatory arrest (HCA) in aortic arch repair for patients with type A aortic dissection (TAAD). This study seeks to examine whether the use of moderate HCA in emergency aortic arch surgery provides comparable operative outcomes to deep HCA for patients with acute TAAD.

METHODS

We prospectively enrolled 74 consecutive patients (mean age 47.7±9.8 years, 54 males) with acute TAAD, who underwent emergency total arch replacement and frozen elephant trunk implantation under HCA (18-28 °C) with unilateral selective antegrade cerebral perfusion (uSACP). Patients were divided into two groups based on the nasopharyngeal temperature at the initiation of HCA: deep HCA (DHCA, <20 °C) in 35 (47.3%) and moderate HCA (MHCA, 20-28 °C) in 39 (52.7%). Operative outcomes including mortality, morbidity and visceral organ functions were compared between the two groups.

RESULTS

The mean times of cardiopulmonary bypass (CPB) and aortic cross-clamp were 211±54 and 238±62 minutes (P=0.053) and 118±27 and 142±45 minutes (P=0.005) in the MHCA and DHCA groups, respectively. Operative mortality did not differ between two groups (10.2% in MHCA vs. 14.3% in DHCA groups, P=0.862). Nor did the incidence of morbidities differ between the two groups (P>0.05). The temporal trend in the changes of postoperative levels of creatinine, aspartate aminotransferase, total bilirubin and lactate did not differ between two groups (P>0.05). Multivariate analysis found that the temperature during HCA (MHCA vs. DHCA) did not affect operative mortality, morbidities and neurologic complications. Instead, CPB time (in minutes) was the risk factor for operative mortality (odds ratio, 1.032; 95% confidence interval, 1.004-1.061; P=0.023).

CONCLUSIONS

Moderate HCA is associated with equivalent operative mortality and morbidity and visceral organ functions compared to deep HCA in patients with acute TAAD undergoing total arch replacement under uSACP. This study implies the clinical safety and efficacy of moderate HCA in emergency aortic arch repair for such patients, which provides equivalent cerebral and visceral organ protection while decreasing CPB and cross-clamp times without increasing the risk of operative mortality and morbidity.