The Choice of Pulmonary Autograft in Aortic Valve Surgery: A State-of-the-Art Primer.

The Ross procedure has long been seen as an optimal operation for a select few. The detractors of it highlight the issue of an additional harvesting of the pulmonary artery, subjecting the native PA to systemic pressures and the need for reintervention as reasons to avoid it. However, the PA is a living tissue and capable of adapting and remodeling to growth. We therefore review the current evidence available to discuss the indications, contraindications, harvesting techniques, and modifications in a state-of-the-art narrative review of the PA as an aortic conduit. Due to the lack of substantial well-designed randomized controlled trials (RCTs), we also highlight the areas of need to reiterate the importance of the Ross procedure as part of the surgical armamentarium.

Long-term Clinical and Echocardiographic Outcomes in Young and Middle-aged Adults Undergoing the Ross Procedure.

Importance: There is no ideal valve substitute for young adults requiring aortic valve replacement. Multicenter data supporting use of the Ross procedure with respect to long-term postoperative valve-related mortality and reintervention, as well as function of the autograft and pulmonary homograft, are needed. Objective: To determine the long-term clinical and echocardiographic outcomes in young and middle-aged patients undergoing the Ross procedure. Design, Setting, and Participants: A retrospective multicenter international cohort study with a median follow-up period of 9.2 years was conducted in 5 experienced centers regularly performing the Ross procedure. Consecutive patients aged 18 to 65 years were included by each center between 1991 and 2018. Main Outcomes and Measures: Survival and autograft-related and homograft-related reintervention. Serial echocardiographic measurements of valve function were analyzed using mixed-effects modeling. Results: During the study period, 1431 patients (74.3% men; n = 1063) were operated on at a median age of 48.5 years (mean [SD], 47.7 [9.5]; range, 18.1-65; interquartile range, 42.7-54.0). Implantation techniques were root inclusion in 355 (24.9%), root replacement in 485 (34.0%), and subcoronary implantation in 587 (41.1%). Right ventricular outflow tract reconstruction was performed with homografts in 98.6% (n = 1189) and bioprostheses in 1.4% (n = 17). Ten patients (0.7%) died before discharge. Median follow-up was 9.2 years (13 015 total patient-years). Survival after 10 and 15 years was 95.1% (95% CI, 93.8%-96.5%) and 88.5% (95% CI, 85.9%-91.1%), respectively. Freedom from autograft and homograft reintervention after 15 years was 92.0% and 97.2%, respectively. Late events were autograft endocarditis in 14 patients (0.11% per patient-year), homograft endocarditis in 11 patients (0.08% per patient-year), and stroke in 37 patients (0.3% per patient-year). Conclusions and Relevance: Given its excellent short-term and long-term outcome in young and middle-aged adults in this study, the Ross procedure should be considered in young and middle-aged adults who require aortic valve replacement. Patients should be referred to an experienced center with a program dedicated to the Ross procedure.

Anatomic Repair of Left Main Coronary Artery Atresia: Coronary Ostioplasty With Autologous Pulmonary Artery.

BACKGROUND: Left main coronary arterial (LMCA) atresia is a rare coronary arterial anomaly with extremely limited data on the optimal management. We aimed to report our single-surgeon experience of the ostioplasty in patients with LMCA atresia. METHODS: From July 2018 to December 2019, pediatric patients who presented with LMCA atresia and subsequently underwent surgical coronary ostioplasty were recruited into this retrospective study. Concomitant mitral repair was applied when the regurgitation was moderate or more severe. RESULTS: A total of 9 patients diagnosed with LMCA atresia were included. Mitral regurgitation was found in all of them, including 6 (66.7%) severe, 1 (11.1%) moderate, and 2 (22.2%) mild. In addition to ischemic lesions, which were found in 7 (77.8%) patients, structural mitral problems were also common (presented in 7 [77.8%] patients). All the patients underwent coronary ostioplasty with autologous pulmonary arterial patch augmenting the anterior wall of the neo-ostium. Mean aortic cross clamp time and cardiopulmonary bypass time was 88.1 ± 18.9 and 124.6 ± 23.6 minutes, respectively. During a median of 10.9 (range: 3.3 to 17.2) months' follow-up, there was only 1 death at 5 months after surgery. All survivors were recovered uneventfully with normal left-ventricular function; however, with 4 (50.0%) having significant recurrence of mitral regurgitation. CONCLUSIONS: With favourable surgical outcomes, coronary ostioplasty for LMCA atresia may be an option of revascularization. Structural mitral problems presented in majority patients, resulting in the requirement of concomitant mitral repair. However, the optimal technique of mitral repair remains unclear.

Long-term results of aortic arch reconstruction with branch pulmonary artery homograft patches.

BACKGROUND: Homograft tissue is an important reconstructive material used in the surgical correction of a variety of congenital heart defects. The aim of this study is to evaluate the long-term outcome of pulmonary artery (PA) branch patches used in the reconstruction of the thoracic aorta in children. METHODS: Retrospective review of 124 consecutive pediatric patients undergoing corrective surgery for their congenital heart defects between 2001 and 2016. Survival, reoperation, and reintervention data were collected, as well as imaging data to assess for presence of recoarctation, dilation, or aneurysm formation in the area of patch reconstruction. RESULTS: Overall 15-year survival was 83.9% and 15-year freedom from reintervention in the area of patch reconstruction was 89.2%. Rates of mortality (0%), cardiac transplantation (0%), and reoperation (0.8%) attributable to the area of patch reconstruction were low. The frequency of catheter-based intervention in the area of patch reconstruction was 9.7%; such interventions were successful in all but one patient, who ultimately underwent successful surgical aortoplasty. CONCLUSIONS: Homograft patches harvested from PA branches are an effective reconstructive material used for reconstruction of the aorta in small children. Long-term results show no risk of aneurysm formation and low rates of stenosis formation.

Pressurized carbon dioxide as a potential tool for decellularization of pulmonary arteries for transplant purposes.

Vascular bio-scaffolds produced from decellularized tissue offer a promising material for treatment of several types of cardiovascular diseases. These materials have the potential to maintain the functional properties of the extracellular matrix (ECM), and allow for growth and remodeling in vivo. The most commonly used methods for decellularization are based on chemicals and enzymes combinations, which often damage the ECM and cause cytotoxic effects in vivo. Mild methods involving pressurized CO2-ethanol (EtOH)-based fluids, in a supercritical or near supercritical state, have been studied for decellularization of cardiovascular tissue, but results are controversial. Moreover, data are lacking on the amount and type of lipids remaining in the tissue. Here we show that pressurized CO2-EtOH-H2O fluids (average molar composition, ΧCO2 0.91) yielded close to complete removal of lipids from porcine pulmonary arteries, including a notably decrease of pro-inflammatory fatty acids. Pressurized CO2-limonene fluids (ΧCO2 0.88) and neat supercritical CO2 (scCO2) achieved the removal of 90% of triacylglycerides. Moreover, treatment of tissue with pressurized CO2-limonene followed by enzyme treatment, resulted in efficient DNA removal. The structure of elastic fibers was preserved after pressurized treatment, regardless solvent composition. In conclusion, pressurized CO2-ethanol fluids offer an efficient tool for delipidation in bio-scaffold production, while pressurized CO2-limonene fluids facilitate subsequent enzymatic removal of DNA.

Mechano-biological adaptation of the pulmonary artery exposed to systemic conditions.

Cardiac surgeries may expose pulmonary arterial tissue to systemic conditions, potentially resulting in failure of that tissue. Our goal was to quantitatively assess pulmonary artery adaptation due to changes in mechanical environment. In 17 sheep, we placed a pulmonary autograft in aortic position, with or without macroporous mesh reinforcement. It was exposed to systemic conditions for 6 months. All sheep underwent 3 ECG-gated MRI's. Explanted tissue was subjected to mechanical and histological analysis. Results showed progressive dilatation of the unreinforced autograft, while reinforced autografts stabilized after two months. Some unreinforced pulmonary autograft samples displayed more aorta-like mechanical behavior with increased collagen deposition. The mechanical behavior of reinforced autografts was dominated by the mesh. The decrease in media thickness and loss of vascular smooth muscle cells was more pronounced in reinforced than in unreinforced autografts. In conclusion, altering the mechanical environment of a pulmonary artery causes changes in its mechano-biological properties.

Maladaptive remodeling of pulmonary artery root autografts after Ross procedure: A proteomic study.

OBJECTIVE: Pulmonary autograft root dilatation is the major long-term complication after Ross procedure and the leading cause for reoperation. However, the mechanisms underlying dilatation remain to be elucidated. This study analyzed the proteomic changes seen in the dilated pulmonary autograft compared with normal pulmonary artery and aorta tissues. METHODS: Pulmonary autograft surgical samples were taken from 9 consecutive patients (mean age 37 ± 14; 15-51 years) with mean diameters of 5.2 ± 0.5 cm (4.6-5.8 cm) reoperated 8 to 16 years after Ross procedure. Control pulmonary artery and aorta samples were from 7 age- and sex-matched cardiac donors. Tunicae mediae from all samples were processed for proteomic analysis via 2-dimensional electrophoresis, matrix-assisted-laser-desorption-ionization-time of flight/mass spectrometry, and bioinformatics. The thus-identified putatively relevant proteins were validated via Western immunoblotting. RESULTS: Pulmonary autograft proteome features differed markedly from control pulmonary arteries, since proteins related to focal adhesions (eg, paxillin), cytoskeleton (eg, vimentin), and metalloprotease-regulating proteoglycans (eg, testican-2) were significantly up-regulated, whereas significant decreases occurred in microfibril-associated glycoprotein1, which controls elastic fiber buildup. Profound changes also occurred in cell-signaling proteins, ie, increases in soluble Jagged-1 fragment and ectodysplasin-2 receptor, and decreases in Notch-1 intracellular domain fragment. Moreover, pulmonary autograft expression levels of Paxillin, Vimentin, Jagged-1 fragment, and Notch1 intracellular domain fragment also differed from those of control aorta. CONCLUSIONS: This study provides the first description of the specific proteomic features of dilated pulmonary autograft tunica media, which separate them sharply not only from those of control pulmonary artery and aorta but also of aortic aneurysms. These findings suggest that dilated pulmonary autografts undergo a unique maladaptive remodeling process deserving further investigation.

Bronchial-arterial-circulation-sparing Lung Preservation: A New Organ Protection Approach for Lung Transplantation.

BACKGROUND: Compromised microvasculature resulting from disrupted bronchial arterial circulation appears to trigger chronic lung allograft dysfunction. Maintaining the microvasculature throughout the transplant process could improve the long-term health of transplanted lungs. We recently developed a bronchial-arterial-circulation-sparing (BACS) lung preservation approach and tested whether this approach would decrease microvascular damage and improve allograft function. METHODS: The lungs of Lewis rats were procured using either the BACS approach, where the bronchial and pulmonary arteries were synchronously perfused; a conventional approach, where only the pulmonary artery was perfused; or a conventional approach with a prostaglandin flush. After 4 hours of cold ischemia, physiologic function and vascular tone of the grafts were evaluated during ex vivo lung perfusion (EVLP), and microvasculature damage was assessed using 2-photon microscopy analysis. Lung function was compared after transplant among the groups. RESULTS: After 4 hours of cold ischemia, the BACS group exhibited significantly higher adenosine triphosphate levels and lower expression of phosphorylated myosin light chain, which is essential for vascular smooth muscle contraction. On EVLP, the BACS and prostaglandin groups showed lower pulmonary vascular resistance and less arterial stiffness. BACS attenuated microvasculature damage in the lung grafts when compared with conventional preservation. After transplantation, the lungs preserved with the BACS approach exhibited significantly better graft function and lower expression of phosphorylated myosin light chain. CONCLUSIONS: Our data suggest that BACS lung preservation protects the dual circulation inherent to the lungs, facilitating robust microvasculature in lung grafts after transplantation, leading to better posttransplant outcomes.

Lung transplantation for pulmonary hypertension with giant pulmonary artery aneurysm.

BACKGROUND: Aneurysm of the main pulmonary artery trunk (PAA) is a rare but severe complicating factor in patients suffering from pulmonary arterial hypertension (PAH). Many centers consider PAA an indication for a heart-lung transplantation. We aimed to summarize our institutional experience with a lung-only strategy in this complex group of patients. METHODS: We performed a retrospective single-center analysis of patients with PAH and a severe PAA who underwent lung transplantation between January 1996 and November 2018. RESULTS: A total of 127 patients with PAH underwent lung transplantation during the study period. Seven patients presented with severe PAA (mean diameter, 70.4 mm). Donor lungs were procured together with the main pulmonary artery (PA). In the recipient, cardiopulmonary bypass with bicaval cannulation was established, and bilateral pneumonectomy together with resection of the entire PA trunk was performed. The right donor lung was implanted, and the attached PA trunk was pulled through behind the superior vena cava and ascending aorta. Anastomosis was performed just above the level of the pulmonary valve. Thereafter, the left lung was implanted by reconnecting the left PA to the main PA trunk. All but 1 patient, who died from sepsis on postoperative day 13, were successfully discharged. CONCLUSIONS: To the best of our knowledge, this is the largest published experience of patients with PAH and severe PAA who underwent lung transplantation. We show that these patients are eligible for double lung transplantation and do not require heart-lung transplantation.

An Unusual Complication of the "Supported" Ross Procedure.

We present a unique surgical complication in a 19-year-old patient who underwent a "supported" Ross procedure for congenital aortic stenosis. In the present case, herniation of pulmonary autograft material through coronary fenestrations in the Dacron supporting material can be appreciated. This case suggests a possible need to modify surgical technique to ensure that all autograft tissue remains contained within the Dacron bolster.

The surgical treatment of anomalous origin of one pulmonary artery from the ascending aorta.

OBJECTIVE: This study sought to summarize the clinical experience of surgical treatment of anomalous origin of pulmonary arteries from the ascending aorta (AOPA) in Fuwai hospital. METHODS: Fifty-two patients (28 males, 17.2 ± 27.2 months old and 8.7 ± 10.2 Kg weight) who have AOPA undertook surgical treatment between 1998 and 2017 were reviewed in this study, 47 out of 52 are anomalous origin of the right pulmonary artery (AORPA), among the rest of the patients are anomalous origin of left pulmonary artery (AOLPA). 27 out of 52 associate with simple cardiac abnormalities, 20 out of 52 associate with complex cardiac malformations, the remaining 5 patients without cardiac abnormalities. Among all patients who underwent surgical treatment, the direct end-to-side anastomosis strategy was applied in 26 patients, autologous pericardial-homograft patch and aortic flap were employed in 20 patients, and synthetic graft was used in 6 patients. RESULTS: No patient died during the perioperative period. 50 out of 52 patients were followed-up for 100.1 ± 70.9 months. The rate of pulmonary arterial free restenosis for 2 years, 5 years, and 10 years is 98.0, 96.0 and 92.0%, respectively. CONCLUSIONS: The correct diagnosis and appropriate surgical treatment for AOPA could obtain excellent early and medium-term result.

Efficacy of stem cell therapy for pulmonary arterial hypertension: a systematic review and meta-analysis of preclinical studies.

BACKGROUND: Despite significant progress in drug treatment, the prognosis of patients with advanced pulmonary arterial hypertension (PAH) remains extremely poor. Many preclinical studies have reported the efficacy of stem cell (SC) therapy for PAH; however, this approach remains controversial. The aim of this systematic review and meta-analysis is to assess the potential efficacy of SC therapy for PAH. METHODS: The Medline, EMBASE, Cochrane Library, and Web of Science databases were searched from inception to August 12, 2018. Preclinical studies that evaluated the use of SC therapy for PAH were included. The primary outcome was pulmonary haemodynamics, as assessed by measurement of the right ventricular systolic pressure (RVSP), mean pulmonary arterial pressure (mPAP), and/or mean right ventricle pressure (mRVP). The secondary outcomes included the weight ratio of the right ventricle to the left ventricle plus septum (RV/LV+S), the right ventricle to body weight ratio (RV/BW), the percentage of pulmonary arteriole area index (WA), and/or the percentage of medial wall thickness of the pulmonary arteriole (WT). The quality of outcomes was evaluated using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) bias risk tool. The inverse-variance method with random-effects modelling was used to calculate pooled weighted mean differences (WMDs) and 95% CIs. Statistical analysis was performed with STATA 14.0. RESULTS: Twenty-eight eligible articles (722 animals) were included. SC therapy reduced the pooled WMDs (95% CIs) of RVSP, mPAP, mRVP, RV/LV+S, RV/BW, WA, and WT for animals with PAH, with values of - 14.12 (- 14.63, - 13.61), - 11.86 (- 12.35, - 11.36), - 17.33 (- 18.10, - 16.56), - 0.10 (- 0.10, - 0.09), 0.23 (0.21, 0.24), - 13.66 (- 15.71, - 11.62), and - 7.96 (- 7.99, - 7.93), respectively. CONCLUSIONS: SC therapy is effective for PAH in preclinical studies. These results may help to standardise preclinical animal studies and provide a theoretical basis for clinical trial design in the future. SYSTEMATIC REVIEW REGISTRATION: PROSPERO ( http://www.crd.york.ac.uk/PROSPERO ).

Technical Varieties of Ross Procedure: A Case Series.

Replacement of aortic valve with the pulmonary autograft is carried out through the Ross procedure due to its potential for growth, durability in pediatric population, and absence of anticoagulation. This case series reports the postoperative outcome of two technical variations of Ross procedure in eight patients who underwent surgery from January 2007 to December 2016. The dominant valvular hemodynamic indication was aortic regurgitation. The techniques employed for Ross procedure included free standing root replacement in six patients and modified root replacement with autograft stabilisation using Dacron interposition graft in two patients. Right ventricular outflow tract (RVOT) conduit reconstruction was achieved by utilisation of Contegra bio prosthesis in four patients; and use of manually constructed valved conduit comprising of PTFE (polytetrafluoroethelene) membrane and bovine pericardial tube in remaining four patients. There was no mortality and no re-intervention. The technical varieties of Ross procedure offer freedom from need of anti-coagulation, mortality, and RVOT conduit failure in younger adults.

External Prosthetic Reinforcement of the Pulmonary Autograft.

BACKGROUND: Neo-aortic root dilatation accounts for the majority of reoperations needed after the Ross procedure with implantation of the pulmonary autograft as complete root replacement. This study evaluates early results of external prosthetic reinforcement of the autograft. METHODS: From July 2015 to October 2017, 16 adolescent and adult patients received a Ross procedure at our department by this technique. A congenital-dysplastic valve was present in 13 patients, including 9 patients with a bicuspid aortic valve. Clinical and echocardiographic follow-up is complete with a mean duration of 19.7 ± 5.8 months. RESULTS: The mean age at operation was 27.1 ± 16.1 years. Mean aortic cross-clamping time was 102 ± 39 minutes. No bleeding complication occurred. The median stay on the intensive care unit was 2 days. In-hospital mortality was 0%. All patients were discharged with no or trivial aortic regurgitation. In one patient both the autograft and homograft were replaced because of endocarditis 3 months after the primary operation, leading to 93.8% freedom from reoperation at 2 years. There were no late deaths during the study period. The latest echocardiography confirmed absence of aortic regurgitation grade >I in all patients. Neo-aortic root diameters remained stable during follow-up. CONCLUSION: The presented modification of the Ross procedure does not prolong ischemia time, and can be performed with a low operative morbidity and mortality and an excellent early valve function.

Three-Patch Aortic Root Reconstruction With Extended Left Main Coronary Artery Patch Augmentation in Neonates and Infants.

Left main coronary artery (LMCA) stenosis is present in approximately 5% of patients with congenital supravalvular aortic stenosis (SVAS) (Fig. 1)1 and is associated with an increased risk of sudden cardiac death.2 However, patients undergoing coronary artery intervention at the time of SVAS repair are at the highest risk of experiencing major adverse cardiac events.3 Literature reports of surgical techniques and outcomes of concomitant coronary artery repair in these high-risk patients are diverse and inconsistently described. We have recently adopted a standardized surgical technique for management of this complex pathology by combining extended LMCA patch augmentation with a 3-patch aortic root reconstruction (Brom's technique). In this report, we describe our contemporary surgical technique of 3-patch aortic root reconstruction with extended LMCA patch augmentation for patients with congenital SVAS with ostial LMCA stenosis and bilateral outflow tract obstruction. Institutional review board approval was obtained for retrospective review of patient charts.

Pulmonary Autograft Mitral Valve Replacement (Ross II): Long-Term Follow-Up of a US Center.

BACKGROUND: Mitral valve replacement (MVR) with a pulmonary autograft (Ross II) may be a useful technique for pediatric and young adult patients who wish to avoid anticoagulation. Our aim was to evaluate the long-term outcomes of the Ross II procedure at our institution. METHODS: Patients undergoing the Ross II procedure between June 2002 and April 2008 were included. Preoperative diagnoses included rheumatic disease (n = 5), congenital mitral valve (MV) pathology (partial atrioventricular canal defect [n = 2], complete atrioventricular canal defect [n = 1], Shone's complex [n = 1]), and myocarditis (n = 1). RESULTS: Ten patients (eight females and two males) between 7 months and 46 years were included. Mean age at surgery was 25.2 ± 15.7 years. There were no in-hospital deaths. Mean follow-up was 11.7 ± 5.2 years. There were three late deaths at 11 months, 5 years, and 11 years, respectively. Causes of death included right heart failure, sepsis, and sudden cardiac arrest. Three patients required subsequent mechanical MVR a median of two years after the Ross II procedure (range: 1-4 years). There was no mortality with reoperation. Echocardiographic follow-up demonstrated mean MV gradients ranging from 2.2 to 9.6 mm Hg. Two patients had greater than mild MV regurgitation postoperatively, and all others had minimal mitral regurgitation or less. Two patients developed moderate MV stenosis. CONCLUSIONS: The Ross II procedure is an option for select older children and young adults desiring a durable tissue MVR to avoid long-term anticoagulation.

Reinforcing the pulmonary artery autograft in the aortic position with a textile mesh: a histological evaluation.

OBJECTIVES: The Ross procedure involves replacing a patient's diseased aortic valve with their own pulmonary valve. The most common failure mode is dilatation of the autograft. Various strategies to reinforce the autograft have been proposed. Personalized external aortic root support has been shown to be effective in stabilizing the aortic root in Marfan patients. In this study, the use of a similar external mesh to support a pulmonary artery autograft was evaluated. METHODS: The pulmonary artery was translocated as an interposition autograft in the descending thoracic aortas of 10 sheep. The autograft was reinforced with a polyethylene terephthalate mesh (n = 7) or left unreinforced (n = 3). After 6 months, a computed tomography scan was taken, and the descending aorta was excised and histologically examined using the haematoxylin-eosin and Elastica van Gieson stains. RESULTS: The autograft/aortic diameter ratio was 1.59 in the unreinforced group but much less in the reinforced group (1.11) (P < 0.05). A fibrotic sheet, variable in thickness and containing fibroblasts, neovessels and foreign body giant cells, was incorporated in the mesh. Histological examination of the reinforced autograft and the adjacent aorta revealed thinning of the vessel wall due to atrophy of the smooth muscle cells. Potential spaces between the vessel wall and the mesh were filled with oedema. CONCLUSIONS: Reinforcing an interposition pulmonary autograft in the descending aorta with a macroporous mesh showed promising results in limiting autograft dilatation in this sheep model. Histological evaluation revealed atrophy of the smooth muscle cell and consequently thinning of the vessel wall within the mesh support.

Patient-specific multiscale computational fluid dynamics assessment of embolization rates in the hybrid Norwood: effects of size and placement of the reverse Blalock-Taussig shunt.

The hybrid Norwood operation is performed to treat hypoplastic left heart syndrome. Distal arch obstruction may compromise flow to the brain. In a variant of this procedure, a synthetic graft (reverse Blalock-Taussig shunt) is placed between the pulmonary trunk and innominate artery to improve upper torso blood flow. Thrombi originating in the graft may embolize to the brain. In this study, we used computational fluid dynamics and particle tracking to investigate the patterns of particle embolization as a function of the anatomic position of the reverse Blalock-Taussig shunt. The degree of distal arch obstruction and position of particle origin influence embolization probabilities to the cerebral arteries. Cerebral embolization probabilities can be reduced by as much as 20% by optimizing graft position, for a given arch geometry, degree of distal arch obstruction, and particle origin. There is a tradeoff, however, between cerebral pulmonary and coronary embolization probabilities.

[Efficacy of coarctation resection and aortoplasty with autologous pulmonary artery patch strategy for treating coarctation of the aorta combined with hypoplastic aortic arch in infants].

Objective: To investigate the outcomes of coarctation resection and aortoplasty with autologous pulmonary artery patch for treating coarctation of the aorta combined with hypoplastic aortic arch in infants. Methods: Clinical data of 21 infants with coarctation of the aorta and hypoplastic aortic arch, who underwent coarctation resection and aortoplasty with autologous pulmonary artery patch in Fuwai hospital from January 2009 to June 2016 were retrospectively analyzed. The age of the patients was 4 (2, 5) months,and the body weight of the patients was (5.3±1.6) kg. The patients were followed up to observe the surgery effect. Results: No perioperative death and serious complications occurred. When the patients were discharged,the systolic blood pressure of the right upper limb was lower than the preoperative systolic blood pressure ((85.7±5.9) mmHg(1 mmHg=0.133 kPa) vs. (100.7±16.6) mmHg, P<0.001),and the systolic blood pressure of the right lower limb was higher than the preoperative systolic blood pressure ((98.7±13.3) mmHg vs. (85.6±20.8) mmHg, P<0.001). The pressure gradient of aortic coarctation detected by echocardiography was lower than the preoperative pressure gradient ((13.1±3.8) mmHg vs. (46.2±17.1) mmHg, P<0.001). No restenosis was detected by echocardiography at discharge. Follow-up data were obtained in 19 patients, and the follow-up time was 18 (8, 45) months.The patients grew well, and no death occurred. Restenosis occurred in 3 cases, 1 patient underwent aortic balloon dilatation and the remaining 2 patients were under follow up observation. Computed tomography angiography showed that the morphology of aortic arch was normal without signs of aortic aneurysm. Conclusion: Coarctation resection with autologous pulmonary artery patch aortoplastystrategy is considered as a safe and effective surgical method for management of infant coarctation with hypoplastic aortic arch, and this surgery method is related with satisfactory early and mid-term outcomes in this patient cohort.

Pulmonary Valve Opening With Two Rotary Left Ventricular Assist Devices for Biventricular Support.

Right ventricular failure is a common complication associated with rotary left ventricular assist device (LVAD) support. Currently, there is no clinically approved long-term rotary right ventricular assist device (RVAD). Instead, clinicians have implanted a second rotary LVAD as RVAD in biventricular support. To prevent pulmonary hypertension, the RVAD must be operated by either reducing pump speed or banding the outflow graft. These modes differ in hydraulic performance, which may affect the pulmonary valve opening (PVO) and subsequently cause fusion, valvular insufficiency, and thrombus formation. This study aimed to compare PVO with the RVAD operated at reduced speed or with a banded outflow graft. Baseline conditions of systemic normal, hypo, and hypertension with severe biventricular failure were simulated in a mock circulation loop. Biventricular support was provided with two rotary VentrAssist LVADs with cardiac output restored to 5 L/min in banded outflow and reduced speed conditions, and systemic and pulmonary vascular resistances (PVR) were manipulated to determine the range of conditions that allowed PVO without causing left ventricular suction. Finally, RVAD sine wave speed modulation (±550 rpm) strategies (co- and counter-pulsation) were implemented to observe the effect on PVO. For each condition, outflow banding had higher PVR (97 ± 20 dyne/s/cm5 higher) for when the pulmonary valve closed compared to reduced speed. In addition, counter-pulsation demonstrated greater PVO than co-pulsation and constant speed. For the purpose of reducing the risks of pulmonary valve insufficiency, fusion, and thrombotic event, this study recommends a RVAD with a steeper H-Q gradient by banding and further exploration of RVAD speed modulation.