Ross Procedure Research Articles

The immediate result of replacing the aortic root with a decellularized valve-containing allograft in a child

Cardiac surgery of the aortic valve in pediatric patients is an urgent problem. Performing an open aortic commissurotomy and planar resection of the valves during the newborn period allows to obtain suboptimal results and postpone subsequent interventions indefinitely. With an unsatisfactory result of open aortic commissurotomy in children of the first years of life, the need to search for optimal surgical tactics arises. The presented article describes the technique of replacing the aortic root with a decellularized valve-containing allograft in a child of 14 months of life. A good immediate result of the operation is associated with the ability of the allograft to provide physiological hemodynamics in the aortic position. The advantages of the described technique are the reduction in the time and complexity of surgical intervention, the possibility of preserving own pulmonary valve, the probability of recellularization and the possibility of graft growth with the growth of the child. That is precisely why the presented technique should be considered as an alternative to Ross surgery, especially if there are anatomical contraindications to it.

Quality of life after Ross procedure in children.

Health-related quality of life in children who have undergone the Ross procedure has not been well characterised. The aim of this study was to characterise health-related quality of life in this cohort and compare to children with other CHD. In this cross sectional, single-centre study, health-related quality of life was assessed in patients who underwent a non-neonatal Ross procedure using the Pediatric Quality of Life Inventory. Ross cohort scores were compared with healthy norms, patients with CHD requiring no surgical intervention or had curative surgery (Severity 2, S2) and patients who were surgically repaired with ≥1 surgical procedure and with significant residual lesion or need for additional surgery (Severity 3, S3). Associations between Pediatric Quality of Life Inventory score and patient factors were also examined. 68 patients completed surveys. Nearly one-sixth of patients had overall scores below the cut-off for at-risk status for impaired health-related quality of life. There was no difference in overall health-related quality of life score between the Ross cohort and healthy children (p = 0.56) and S2 cohort (p = 0.97). Health-related quality of life was significantly higher in the Ross cohort compared to S3 cohort (p = 0.02). This difference was driven by a higher psychosocial health-related quality of life in the Ross cohort as compared to S3 cohort (p = 0.007). Anxiety scores were significantly worse in the Ross cohort compared to both S2 (p = 0.001) and S3 (p = 0.0017), respectively. Children who have undergone a Ross procedure report health-related quality of life equivalent to CHD not requiring therapy and superior to CHD with residual lesions. Despite these reassuring results, providers should be aware of potential anxiety among Ross patients.

Long-Term Outcomes after Aortic Valve and Root Replacement in a Very High-Risk Population.

Background: Aortic valve and root replacement (AVRR) is a standardised procedure to treat patients with aortic valve and root disease. In centres with a well-established aortic valve and root repair program (valve repairs and Ross operations), only patients with very complex conditions receive AVRR; this procedure uses a mechanical or biological composite valve graft (modified Bentall–de Bono procedure). The aim of the study was to evaluate the short- and long-term results after AVRR in a high-risk population with complex pathologies. Methods: Between 2005 and 2018, a total of 273 consecutive patients (mean age 64 ± 12.8 years; 23% female) received AVRR. The indication for surgery was an acute type A aortic dissection in 18%, infective endocarditis in 36% and other pathologies in 46% patients; 39% were redo procedures. The median EuroSCORE II was 11.65% (range 1.48–95.63%). Concomitant surgery was required in 157 patients (58%). Results: The follow-up extended to 5.2 years (range 0.1–15 years) and it was complete in 96% of the patients. The 30-day mortality was 17%. The overall estimated survival at 5 and 10 years was 65% ± 3% and 49% ± 4%, respectively. Univariate and multivariate logistic regression analyses revealed the following risk factors for survival: perioperative neurological dysfunction (OR 5.45), peripheral artery disease (OR 4.4) and re-exploration for bleeding (OR 3.37). Conclusions: AVRR can be performed with acceptable short- and long-term results in a sick patient population. The Bentall–De Bono procedure may be determined to be suitable for only elderly or high-risk patients. Any other patients should receive an AV repair or the Ross procedure in well-established centres.

Ross Procedure in the era of Handmade-Valved Conduits for Right Ventricular Outflow Tract Reconstruction in Children: Short-Term Surgical Outcomes.

ObjectiveRoss procedure is considered as the “gold standard” for aortic valve replacement, but the conduits used for right ventricular outflow tract (RVOT) reconstruction, such as homografts and bovine jugular vein (BJV) conduits, are of limited availability in China. Handmade expanded polytetrafluoroethylene-valved conduits (HVCs) have been used recently as the alternative for RVOT reconstruction, but their specific experience in Ross procedure is limited in the literature.MethodsThis was a retrospective review of 27 children who underwent Ross procedure in our center from January 2018 to January 2022.ResultsMean age at surgery was 8.0 ± 3.8 years. During the study period, BJV conduits were used for RVOT reconstruction in 6 patients (22%), and HVCs were used in 21 patients (78%). Median conduit size was 20 mm (range, 16–24 mm), and mean conduit Z-score was +0.8 ± 0.9. Median time for cardiopulmonary bypass was 158 min (range, 109–275 min), and mean time for aortic crossclamping was 110 ± 21 min. There was no early mortality. During a median follow-up time of 1.4 years (range, 0.1–3.7 years), 3 patients (11%) with BJV conduits had peak conduit velocity of > 3.5 m/s; 3 patients (11%) with HVCs developed moderate conduit insufficiency; no patients had more than moderate conduit insufficiency. Three patients with BJV conduits had 5 reinterventions, and all received conduit replacement with HVCs.ConclusionHVC is an appealing alternative to BJV conduit for RVOT construction for children undergoing Ross procedure, with favorable short-term outcomes.

Reoperations After the Ross Procedure

Complexity and Outcome of Reoperations After the Ross Procedure in the Current EraThe Annals of Thoracic SurgeryPreviewThe Ross procedure has several advantages, but the need for reintervention is inevitable. The aim of this study was to examine the complexity and outcomes of reoperation after the Ross procedure. Full-Text PDF

Aortic Stenosis in the Low-Risk Patient: Overview of the Management Options and Possible Permutations.

Young and low-risk patients with aortic stenosis pose a clinical dilemma. The need for life-long anticoagulation with mechanical prostheses, the risk of early degeneration of stented and stentless bioprostheses, the unknown long-term outcomes of transcatheter valve implantation and the high surgical risk of a Ross procedure all have long-term implications namely with regards to re-operation strategy. Aortic valve intervention can take several forms: surgical valve replacement with a stented or stentless bioprosthesis or with a mechanical prosthesis, transcatheter aortic valve implantation (TAVI), and the Ross procedure.1 While the choice of strategy is often straightforward in the elderly and high-risk population, young and low-risk patients with aortic stenosis are challenging to the Heart Team, namely because of their longer life expectancy, and higher cumulative life-time risk of valve-related complications.1 Herein, we review the currently available options for first and subsequent interventions for managing aortic stenosis in low-risk patients.

Complexity and Outcome of Reoperations After the Ross Procedure in the Current Era

BackgroundThe Ross procedure has several advantages, but the need for reintervention is inevitable. The aim of this study was to examine the complexity and outcomes of reoperation after the Ross procedure. MethodsRetrospective chart review was performed of patients with a prior Ross procedure who underwent reoperation at our institution from September 1991 to January 2021. Demographic, echocardiographic, surgical, and perioperative data were collected. Descriptive statistical and regression analyses were performed. ResultsA total of 105 patients underwent a reoperation at Mayo Clinic after the initial Ross procedure performed at our institution (n = 16; 16.2%) or elsewhere (n = 83; 83.8%). Mean age at the Ross procedure was 27 ± 17 years, and mean age at reoperation at our institution was 37 ± 19 years. Indications for surgical procedure varied, but 64% had autograft regurgitation as 1 of their indications for reoperation. Autograft interventions were performed in 78 patients (74.2%). Pulmonary valve or conduit replacement was performed in 56 patients (53.3%). Double root replacement was performed in 11 patients (10.5%). Aortic reconstruction was performed in 37 patients (38.4%). There were 5 early deaths (5%). During a median follow-up of 6.25 years (3 months–24 years), late deaths occurred in 14 patients (13.1%). Patients with ejection fraction <30% on preoperative echocardiography had shorter duration between the Ross procedure and subsequent reoperation (P = .03). ConclusionsReoperations after the Ross procedure are performed for a wide range of indications, with most due to autograft dysfunction. The number of early deaths is not low. Reoperation after the Ross procedure should be advised before left ventricular systolic dysfunction.

Surgical outcomes of pulmonary valve infective endocarditis: A US population-based analysis

BackgroundPulmonary valve infective endocarditis (PVIE) represents a rare subset of right-sided IE. This study aimed to evaluate the population-level surgical outcomes of PVIE in the United States. MethodsWe performed a retrospective observational study using the 2002–2017 National Inpatient Sample database. We included hospitalizations with both IE and PV interventions. We excluded Tetralogy of Fallot, congenital PV malformation, and those who underwent the Ross procedure. The primary outcome was in-hospital mortality. The secondary outcomes included major complications and length of hospital stay. ResultsWe identified 677 PVIE hospitalizations that underwent surgical treatment, accounting for 0.06% of all IE hospitalizations. The mean age was 35.2 ± 1.7 years; 60.0% were White, 30.3% were women, and 11.4% were intravenous drug users. Most were treated in large-sized (70.1%) urban teaching (88.8%) hospitals. Close to 30% of patients received at least one concomitant valve procedure. The in-hospital mortality was 5.5% for the entire cohort, and the median length of stay was 16 days. Major complications included complete heart block (8.7%), acute kidney injury (8.1%), and stroke (1.3%). The differences in mortality and complications rate comparing PV repair and replacement were not statistically significant. PV repair was associated with a longer length of hospital stay compared to PV replacement (median: 25 vs. 16 days, p = 0.03). ConclusionsThis study defines the population-level in-hospital outcomes after surgical intervention of PVIE. Surgically treated PVIE patients are associated with relatively low mortality and morbidities. The outcomes between PV replacement and repair are similar.

Outcomes of redo operations after the Ross procedure

BackgroundThe Ross procedure is not commonly performed, owing to the procedural complexity and the risk of autograft and/or homograft reoperation. This study examined outcomes of patients undergoing Ross reinterventions at a dedicated Ross center. MethodsWe retrospectively reviewed 225 consecutive patients who underwent a Ross procedure between 1994 and 2019. Index and redo operation characteristics and outcomes were compared between patients with and those without redo operations. Multivariate analysis was used to identify independent predictors of Ross-related reinterventions. Survival was estimated with Kaplan–Meier analysis. ResultsSixty-six patients (29.3%) required redo Ross surgery, 41 patients (18.2%) underwent autograft reoperation only, 8 patients (3.6%) had a homograft reintervention, and 17 patients (7.6%) had both autograft and homograft reoperations (12 as a combined procedure and 5 as sequential procedures). The mean time to reintervention was 11 ± 6 years for autograft reoperations and 12 ± 7 years for homograft reoperations. Patients who underwent Ross-related reinterventions were younger (mean, 38 ± 11 years vs 43 ± 11 years; P < .01) and had a higher rate of New York Heart Association class III/IV (56% vs 38%; P = .02) at the index Ross procedure. Most patients undergoing autograft reintervention had aortic insufficiency and/or aneurysm (98.2%; 57 of 58). The primary reason for homograft reintervention was pulmonary stenosis (92%; 23 of 25). The operative mortality of Ross reintervention was 1.5% (1 of 66). Survival at 15 years was similar in patients who required a redo operation and those who did not (91.2% vs 93.9%; P = .23). ConclusionsRoss reinterventions can be performed safely and maintain patients at the normal life expectancy restored by the index Ross procedure up to 15 years at experienced centers.

ROSS procedure versus mechanical valve replacement in young and middle-aged adults with aortic valve disease

Background: Aortic valve replacement (AVR) remains the only treatment that was revealed to advance the natural history in the cases with severe symptomatic aortic valve disorder. However, aortic valve diseases were challenging in young and adults in middle age persons. The aim of our study: was to compare the mid-term outcomes, quality of life and adverse valve- related events among patients undergoing the Ross procedure and those receiving a mechanical aortic valve . Patients and Methods: This study included patients with aortic valve disease divided into Fifty patients were candidates for ROSS procedure and the other Fifty were for mechanically aortic valve replacement after obtaining the approval of the local ethical committee. Results: Ross patients show statistically significant lower MLHFQ scores compared to Mechanical valve patients; however, a nonsignificant change was found among the study groups in terms of major cardiovascular events or mortality. Conclusion: Mechanical AVR is accompanied by low morbidities and mortalities in both the short and long term. Our data suggest that The Ross operation may be accomplished securely and reproducibly in properly particular cases with lower morbidity and mortality and better quality of life.

Treatment of valvular heart disease in young patients-"early evidence" versus"latest fashion".

Is the performance of locally manufactured mechanical valve prostheses relevant for modern cardiac surgery, in which mechanical valve replacement has become a rarity? This question comes to mind reading the article in this issue of the Journal demonstrating equal outcomes of the TTK Chitra tilting disk mechanical heart valve prostheses in comparison to the SJM bi-leaflet blockbuster. The evidence documenting efficacy of mechanical valve replacement stems from the early ages of cardiac surgery, but often demonstrates superior outcomes in terms of survival and hemodynamics. Yet, the latest fashion in the Western world consists biological choices in combination with new transcatheter techniques (valve in valve options) or the Ozaki or Ross procedures. As long-term results are often missing and documented advantages for mechanical valves stems from early evidence, the local emphasis of mechanical valve replacement may possibly result in superior individual prognoses compared to following the Western world's latest fashions. Individual patient information and decision making moves into focus.

Aorto-Left Ventricular Tunnel - Prenatal Diagnosis and Outcome.

Aorto-left ventricular tunnel (ALVT) is an extremely rare, albeit prenatally detectable, extracardiac channel that connects the ascending aorta to the cavity of the left ventricle. All ALVTs diagnosed prenatally (2006-2020) in five tertiary referral centers were retrospectively assessed for prenatal ultrasound findings, intrauterine course, postnatal outcome, and surgical treatment. We focused on the size of the tunnel and alterations of perfusion of the left ventricular outflow tract and aortic arch. 11 fetuses were diagnosed with ALVT at a mean gestational age of 24.8 weeks. All cases were associated with severe dilatation of the left ventricle and a to-and-fro flow in the left outflow tract. Signs of congestive heart failure were present in five fetuses, four of which were terminated and one of which died in the neonatal period. One fetus died in utero at 34 weeks without prior signs of cardiac failure. Of the five survivors, two underwent the Ross procedure. In both cases the prenatal left ventricular outflow was exclusively via a large tunnel. The remaining three neonates underwent patch closure of the tunnel. In these cases, the prenatal outflow of the left ventricle was via the aortic valve and simultaneously over the tunnel. Prenatal diagnosis of ALVT should be considered in the presence of left ventricular hypertrophy, dilatation of the aortic root, and to-and-fro flow in the aortic outflow tract. Signs of heart failure are associated with an unfavorable outcome. Large tunnels, particularly in combination with the absence of flow over the aortic valve, may be an unfavorable predictor of surgical repair.

Valve-sparing root replacement after the Ross procedure

ObjectivesThe Ross procedure is a preferred treatment for infants and children with aortic valve disease. Progressive neoaortic root dilation and neoaortic insufficiency can occur after the Ross procedure, and because of the young age of these patients, valve-sparing aortic root replacement procedures have advantages compared with the Bentall procedure. The aim of this study is to describe our experience with different techniques of aortic valve-sparing root replacement in this unique cohort of patients. MethodsPatients undergoing valve-sparing aortic root replacement with a history of the Ross procedure between January 2001 and March 2021 were identified. A retrospective chart review was performed, and clinical characteristics of these patients were analyzed. The results of different types of valve-sparing aortic root replacement were also compared. ResultsForty-two patients who had previously undergone a Ross procedure in childhood presented for reintervention for neoaortic root or valve pathology. Seventeen of these patients were considered for valve-sparing aortic root replacement but underwent bioprosthetic or mechanical valve replacement, and 25 patients underwent successful valve-sparing aortic root replacement. Patients who underwent valve-sparing aortic root replacement received a traditional aortic root remodeling procedure with or without suture annuloplasty (Yacoub technique, group 1, n = 7), an aortic root reimplantation procedure (David technique, group 2, n = 11), or a modified root remodeling procedure that also used a geometric annuloplasty ring (group 3, n = 7). Patient demographics and comorbidities were similar between groups. Mean follow-up for these 3 cohorts was 14 years, 4 years, and 1 year, respectively. Overall survival was good, with 1 early death due to hemorrhage in group 2 and 1 death due to malignancy in group 1. Eight patients (7 in group 1; 1 in group 2) required subsequent aortic valve replacements due to neoaortic insufficiency, whereas none in group 3 have required any reintervention. Overall, patients requiring valve replacement after valve-sparing aortic root replacement had lower grades of preoperative neoaortic insufficiency and higher grades of postoperative neoaortic insufficiency. Greater than mild postoperative neoaortic insufficiency was associated with the need for subsequent neoaortic valve replacement. ConclusionsValve-sparing aortic root replacement is safe in patients with a prior Ross procedure. Reimplantation offers superior durability compared with the traditional remodeling procedure. Greater than mild neoaortic insufficiency on postoperative echocardiogram should prompt additional attempts at valve repair. A modified remodeling procedure with geometric ring annuloplasty that is personalized to the patient's individual anatomy is safe with good short-term results, but longer follow-up is needed.

Technique and Not Preoperative Factors Determine Ross Outcomes

Unicuspid Aortic Valve in Patients Undergoing the Ross ProcedureThe Annals of Thoracic SurgeryPreviewThe prevalence and outcomes of the unicuspid aortic valve (UAV) in patients undergoing the Ross procedure have been strongly underreported in the current literature. We sought to evaluate this in comparison with bicuspid (BAV) and tricuspid valve (TAV) in our Ross cohort. Full-Text PDF

The role of mechanical valves in the aortic position in the era of bioprostheses and TAVR: Evidence-based appraisal and focus on the On-X valve

Patients who need a prosthetic aortic heart valve may decide, working with their cardiologist and cardiac surgeon, among a variety of options: surgical or transcatheter approach, bioprosthetic or mechanical valve, or a Ross procedure if suitable to their age and anatomy. This review article examines the evidence for survival benefit with mechanical aortic valves, discusses bioprosthetic structural valve degeneration and its consequences, and considers the risks of redo aortic valve surgery or subsequent valve-in-valve (ViV) transcatheter intervention. It highlights the unique characteristics of the On-X aortic valve, including the US Food and Drug Administration approved and American College of Cardiology/American Heart Association guideline supported reduced anticoagulation target INR of 1.5 to 2.0, and discusses the PROACT Xa trial comparing apixaban vs warfarin anticoagulation. The choice of prosthetic valve should be individualized, carefully considering each patient's unique circumstances. In that context, the On-X aortic valve offers a potential lifetime solution without need for a repeat operation, while minimizing the risks of long-term anticoagulation. In an era of enthusiasm for bioprosthetic and transcatheter-based approaches, the option of a second-generation bileaflet mechanical valve with optimized hemodynamics—the On-X aortic valve—may well align with patient expectations.

Ross procedure in neonates and infants: A valuable operation with defined limits

ObjectiveThe Ross procedure is an important tool that offers autologous tissue repair for severe left ventricular outflow tract (LVOT) pathology. Previous reports show that risk of mortality is highest among neonates and infants. We analyzed our institutional experience within this patient cohort to identify factors that most affect clinical outcome. MethodsA retrospective chart review identified all Ross operations in neonates and infants at our institution over 27 years. The entire study population was analyzed to determine risk factors for mortality and define outcomes for survival and reintervention. ResultsFifty-eight patients underwent a Ross operation at a median age of 63 (range, 9-156) days. Eighteen (31%) were neonates. Eleven (19%) patients died before hospital discharge. Multiple regression analysis of the entire cohort identified young age (hazard ratio [HR], 1.037; P = .0045), Shone complex (HR, 17.637; P = .009), and interrupted aortic arch with ventricular septal defect (HR, 16.01; P = .031) as independent predictors of in-hospital mortality. Receiver operating characteristic analysis (area under the curve, 0.752) indicated age younger than 84 days to be the inflection point at which mortality risk increases. Of the 47 survivors, there were 2 late deaths with a mean follow-up of 6.7 (range, 2.1-13.1) years. Three patients (6%) required LVOT reintervention at 3, 8, and 17.5 years, respectively, and 26 (55%) underwent right ventricular outflow tract reintervention at a median of 6 (range, 2.5-10.3) years. ConclusionsRoss procedure is effective in children less than one year of age with left sided obstructive disease isolated to the aortic valve and/or aortic arch. Patients less than 3 months of age with Shone or IAA/VSD are at higher risk for morbidity and mortality. Survivors experience excellent intermediate-term freedom from LVOT reintervention.

Survival and freedom from reoperation after the Ross procedure in a Russian adult population: A single-center experience

ObjectivesTo evaluate our 12-year experience with the Ross procedure in adults. MethodsA retrospective analysis of 215 cases of the Ross procedure was performed. The mean age of the patients was 36 ± 11.1 years, and the male to female ratio was 75% to 25%, respectively. The pulmonary autograft was placed into the aortic position using the full-root replacement technique and its modified versions. The right ventricular outflow tract was reconstructed using a pulmonary homograft in all cases. ResultsThe 30-day mortality after the operation was 0.9% (2 patients). The median duration of follow-up was 6.1 years (interquartile range, 6.5 years) and was complete in 86% of cases. The survival at 12 years was 94.7% and was comparable with the survival rate of the general population matched for age and sex. At the end of the follow-up, freedom from reoperation due to pulmonary autograft and homograft dysfunction was 89.1% and 99%, respectively. ConclusionsIn our series, the Ross procedure resulted in low early mortality and excellent survival in adults. The long-term survival was not statistically different from the survival of the general population. The pulmonary homograft offered an excellent durability and freedom from reoperation.

Early Outcomes of Patients Undergoing Neoaortic Valve Repair Incorporating Geometric Ring Annuloplasty.

During congenital heart surgery, the pulmonary valve and root may be placed into the systemic position, yielding a "neoaortic" valve. With the stress of systemic pressure, the pulmonary roots can dilate, creating aneurysms and/or neoaortic insufficiency (neoAI). This report analyzes the early outcomes of patients undergoing neoaortic valve repair incorporating geometric ring annuloplasty. Twenty-one patients underwent intended repair at six centers and formed the study cohort. Thirteen had previous Ross procedures, five had arterial switch operations, and three Fontan physiology. Average age was 21.7 ± 12.8 years (mean ± SD), 80% were male, and 11 (55%) had symptomatic heart failure. Preoperative neoAI Grade was 3.1 ± 1.1, and annular diameter was 30.7 ± 6.5 mm. Valve repair was accomplished in 20/21, using geometric annuloplasty rings and leaflet plication (n = 13) and/or nodular release (n = 7). Fourteen had neoaortic aneurysm replacement (13 with root remodeling). Two underwent bicuspid valve repair. Six had pulmonary conduit changes, one insertion of an artificial Nodulus Arantius, and one resection of a subaortic membrane. Ring size averaged 21.9 ± 2.3 mm, and aortic clamp time was 171 ± 54 minutes. No operative mortality or major morbidity occurred, and postoperative hospitalization was 4.3 ± 1.4 days. At discharge, neoAI grade was 0.2 ± 0.4 (P < .0001), and valve mean gradient was ≤20 mm Hg. At average 18.0 ± 9.1 months of follow-up, all patients were asymptomatic with stable valve function. Neoaortic aneurysms and neoAI are occasionally seen late following Ross, arterial switch, or Fontan procedures. Neoaortic valve repair using geometric ring annuloplasty, leaflet reconstruction, and root remodeling provides a patient-specific approach with favorable early outcomes.

Unicuspid Aortic Valve in Patients Undergoing the Ross Procedure

BackgroundThe prevalence and outcomes of the unicuspid aortic valve (UAV) in patients undergoing the Ross procedure have been strongly underreported in the current literature. We sought to evaluate this in comparison with bicuspid (BAV) and tricuspid valve (TAV) in our Ross cohort. MethodsThis was a retrospective observational study of patients undergoing the Ross procedure at 2 dedicated centers between 2009 and 2020. Primary end points were the risks of midterm autograft reoperation and the onset of at least moderate aortic regurgitation during follow-up. The secondary end point was to compare the perioperative outcomes between the groups. ResultsIncluded in the analysis were 286 patients, of those 39% with UAV, 52% with BAV, and 9% with TAV. UAV patients were operated on at the youngest age (P < .001) and more often for a combined hemodynamic aortic valve pathology (P = .02). They had the largest aortic root dimensions: annulus (P = .01), Valsalva sinuses (P = .11), sinotubular junction (P = .001), and ascending aorta (P < .0001). The risks of reoperation (P = .86) and the onset of aortic regurgitation (P = .75) were comparable among the groups over the follow-up of 4.1 years. There was no difference in perioperative outcomes. ConclusionsUAV is a separate unit characterized by a distinct hemodynamic pathology and generated aortopathy. It is not associated with a higher risk of reoperation or new onset of aortic regurgitation after the Ross procedure in the midterm postoperatively. At the current state, UAV remains acceptable for the Ross procedure.

A Rodent Model of The Ross Operation: Syngeneic Pulmonary Artery Graft Implantation in A Systemic Position

The Ross operation for aortic valve disease has regained new interest due to its outstanding long-term results. Nonetheless, when employed as freestanding root replacement, the possible dilation of the pulmonary autograft and subsequent aortic regurgitation is described. Several animal models have been proposed. However, these are usually limited to ex-vivo models or in-vivo experiments with relatively expensive large animal models. In this study, we sought to establish a rodent model of pulmonary artery graft (PAG) implantation in a systemic position. A total of 39 adult Lewis rats were included. Immediately after euthanasia, the pulmonary root was harvested from a donor animal (n=17). Syngeneic recipient (n=17) and sham-operated (n=5) rats were sedated and ventilated. In the recipient group, the PAG was implanted with an end-to-end anastomosis in infra-renal abdominal aortic position. Sham-operated rats underwent only transection and re-anastomosis of the aorta. Animals were followed with serial ultrasound studies for two months and post-mortem histological analysis. The median PAG diameter in the native position was 3.20 mm (IQR=3.18-3.23). At follow-up, the median diameter of the PAG was 4.03 mm (IQR=3.74-4.13) at 1 week, 4.07 mm (IQR=3.80-4.28) at 1 month, and 4.27 mm (IQR=3.90-4.35) at 2 months (p<0.01). Peak systolic velocity was 220.07 mm/s (IQR=210.43-246.41) at 1 week, 430.88 mm/s (IQR=375.28-495.56) at 1 month, and 373.68 mm/s (IQR=305.78-429.81) at 2 months (p=0.02) and did not differ from the sham-operated group at the end of the experiment (p=0.5). Histological analysis did not show any sign of endothelial thrombosis. This study showed that rodent models may allow for the evaluation of the long-term adaptation of the pulmonary root to a high-pressure system. A systemically placed syngeneic PAG implantation represents a simple and feasible platform for the development and evaluation of novel surgical techniques and drug therapies to further improve the outcomes of the Ross operation.