Valve-sparing Root Replacement Research Articles

The Aortic Root in Acute Type A Dissection: Repair or Replace?

BackgroundThe effect of an “aggressive” approach on the aortic root in acute type A aortic dissection (ATAAD) remains insufficiently explored. MethodsRetrospective analysis was conducted between 1992 and 2020 of a single-center, prospective cohort of consecutive patients aged ≥18 years diagnosed with ATAAD. Patients were divided into 2 groups: aortic root replacement (ARR; prosthetic or valve-sparing root replacement, n = 141) and conservative root approach (CRA; root sparing of partially dissected root, n = 90; and supracoronary ascending replacement in nondissected root, n = 68). Inverse probability weighting was used to compare patients with different preoperative characteristics. Mean follow-up was 5.1 (0-21) years in ARR and 7.1 (0-25) years in CRA. ResultsThe frequency of ARR increased over the years, with 19% and 78% of patients undergoing ARR in the earliest and most recent periods, respectively. Early mortality decreased over the years, despite a more aggressive approach, and remained lower in ARR. CRA was associated with a higher hazard of late mortality (hazard ratio, 1.38; 95% CI, 1.12-1.68; P = .001) and reintervention (hazard ratio, 2.08; 95% CI, 1.44-3.56; P = .001). After CRA, new-onset aortic valve insufficiency was a common cause of reintervention. ConclusionsOver the years, there was a gradual increase in the root replacement approach in ATAAD. Root replacement was associated with better long-term survival and fewer reinterventions compared with the conservative approach, whereas the in-hospital mortality decreased during these years. Hence, aggressive root replacement is safe and may be applied in ATAAD with good long-term clinical results, without increased hospital mortality.

The ascending aorta valve-sparing prosthetics with abnormal location of the coronary artery circumflex

Highlights. The combination of congenital aortic valve insufficiency and abnormal coronary artery discharge is rare. Taking into account the fact that coronary angiography is not indicated for young patients, there may be a risk of injury to the coronary artery during the correction of aortic malformation. The published case indicates the need for routine coronary angiography for all patients, regardless of their age, who are going to have aortic valve surgery.Background. Anomalous origin from right sinus and pathway of circumflex coronary artery can complicate aortic valve and root procedures. Computed tomography scan with contrast and selective angiography help to recognize the malformation and protect circumflex artery. Herein we present the case of valve sparing root replacement in patient with bicuspid regurgitant aortic valve and anomalous origin of circumflex artery.

Extended Aortic Repair for Acute Type A Aortic Dissection with Rupture and Malperfusion Complicated with Ehlers-Danlos Syndrome

The patient was a 54-year-old gentleman with sudden chest pain. He suffered from cardiac tamponade and malperfusion of the left carotid artery and the right lower extremity due to acute type A aortic dissection. Rupture of the aortic root and a huge entry from the transverse arch to the proximal descending aorta were found. Extended repairs of valve-sparing root replacement and total arch replacement with frozen elephant trunk were successfully performed. He was discharged without any complications. He was finally diagnosed as having vascular Ehlers-Danlos syndrome by a genetic examination.

David Procedure as Valve-Sparing Root Replacement.

Composite replacement of the aortic root and aortic valve is a valid surgical strategy in a case of annuloaortic ectasia. However, valve-sparing root replacement procedures have become the gold standard in cases with a morphologically intact or at least repairable aortic valve, and offer several advantages compared to conventional replacement techniques. Above all, the David procedure has become established as a well-known valve-sparing root replacement strategy with excellent short- and long-term outcomes, and it has been further applied to additional patient populations with characteristics like a bicuspid aortic valve or in the setting of acute type A aortic dissection. This narrative review offers an overview of the indications as well as the surgical steps of the T. David V procedure, and highlights important key points regarding the surgical feasibility and criteria of patient selection for valve-sparing root replacement.

Risk factors for impaired neurological outcome after thoracic aortic surgery.

BackgroundWe aimed to identify risk factors for an impaired postoperative neurological outcome after thoracic aortic surgery.MethodsData from all patients undergoing thoracic aortic surgery between 2010 and 2020 at our institution were collected and analyzed retrospectively. Logistic regression analysis was used to identify independent risk factors for permanent postoperative neurological deficit (ND) (stroke), which was defined as a ND lasting at least seven days.ResultsThoracic aortic surgery was performed in 1,334 patients. Of these, 286 (21.4%) underwent emergency surgery. The mean EuroSCORE II was 8.6±10.1. A perioperative stroke occurred in 94 patients (7.0%). Of all strokes, 62.8% (n=59) were considered of embolic and 24.5% (n=23) of hemodynamic origin. In elective procedures, stroke rates ranged from 0.5% after valve-sparing root replacement to 8.1% after arch surgery. Adjusted logistic regression identified advanced age [>70 years; odds ratio (OR), 1.83; P=0.009], acute type A dissection (ATAD) (OR, 1.69; P=0.0495), aortic arch surgery (OR, 3.24; P<0.001), concomitant coronary artery bypass grafting (CABG) (OR, 2.19; P=0.005), and high extracorporeal circulation (ECC) time (>230 min; OR, 1.70; P=0.034) as independent risk factors for all strokes. Secondary endpoint analyses revealed that risk factors for hemodynamic stroke were arch surgery, advanced age (>70 years), atherosclerosis, and ATAD. Risk factors for embolic stroke were arch surgery, concomitant CABG and preoperative cerebral malperfusion.ConclusionsIdentified independent risk factors for all strokes were advanced age, ATAD, arch surgery, concomitant CABG, and high ECC time. Hemodynamic and embolic strokes show distinct risk profiles.

Early and long-term outcomes of conventional and valve-sparing aortic root replacement

ObjectiveTo determine the early and long-term outcomes of conventional aortic root (ARR) and valve-sparing root replacement (VSRR) using a standard perioperative and operative approach.MethodsWe present prospectively collected data of 609...

A Pilot Study Characterizing Flow Patterns in the Thoracic Aorta of Patients With Connective Tissue Disease: Comparison to Age- and Gender-Matched Controls via Fluid Structure Interaction

Prior computational and imaging studies described changes in flow patterns for patients with Marfan syndrome, but studies are lacking for related populations. This pilot study addresses this void by characterizing wall shear stress (WSS) indices for patients with Loeys-Dietz and undifferentiated connective tissue diseases. Using aortic valve-based velocity profiles from magnetic resonance imaging as input to patient-specific fluid structure interaction (FSI) models, we determined local flow patterns throughout the aorta for four patients with various connective tissue diseases (Loeys-Dietz with the native aorta, connective tissue disease of unclear etiology with native aorta in female and male patients, and an untreated patient with Marfan syndrome, as well as twin patients with Marfan syndrome who underwent valve-sparing root replacement). FSI simulations used physiological boundary conditions and material properties to replicate available measurements. Time-averaged WSS (TAWSS) and oscillatory shear index (OSI) results are presented with localized comparison to age- and gender-matched control participants. Ascending aortic dimensions were greater in almost all patients with connective tissue diseases relative to their respective control. Differences in TAWSS and OSI were driven by local morphological differences and cardiac output. For example, the model for one twin had a more pronounced proximal descending aorta in the vicinity of the ductus ligamentum that impacted WSS indices relative to the other. We are optimistic that the results of this study can serve as a foundation for larger future studies on the connective tissue disorders presented in this article.

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.

Treatment of the Aortic Root in Acute Aortic Dissection Type A: Insights from the German Registry for Acute Aortic Dissection Type A (GERAADA) Registry.

Surgery of the aortic root in acute aortic dissection type A (AADA) remains a topic of vague evidence since the extend of dissection and surgeons' capability and interpretation of the disease vary remarkably. We aimed to interpret root operation strategies in the German Registry for Acute Aortic Dissection (GERAADA) cohort. GERAADA collected the data of 56 centers between July 2006 and June 2015. A total of 3382 patients undergoing operations for AADA were included and divided into three groups according to aortic root procedure types: supracommissural replacement (SCR), conduit replacement (CR) and valve sparing root replacement (VSRR). Patients in SCR (2425, 71.7%) were significantly older than CR (681, 20.1%) and VSRR (276, 8.2%) (63.4 vs 57.5 vs 54.2 yrs; p < 0.001), more female (38.9 vs 32.0 vs 26.1%; p < 0.001) and presented with less aortic regurgitation (26.3 vs 57.1 vs 56.5%; p < 0.001). VSRR presented with slightly less multiple organ malperfusion (11.6 vs 12.0 vs 10.9%; p = 0.045) and were more often diagnosed for Marfan syndrome (2.4 vs 5.1 vs 9.1%; p < 0.001). Thirty-day mortality was lower for VSRR (11.6%) compared to SCR (16.1%) and CR (19.8%; p = 0.010). Despite longer procedural times multivariable regression showed no influence of total arch replacement for VSRR on mortality compared to CR (OR 0.264; 95% CI, 0.033-2.117; p = 0.21). SCR remains the procedure of choice in elderly and compromised patients. Extended root preservation techniques may be applied even in combination with extended aortic arch surgery for selected patients for AADA with promising early outcomes.

Impact of aortic valve effective height following valve-sparing root replacement on postoperative insufficiency and reoperation

BackgroundThis study evaluated the impact of anatomic aortic root parameters during valve-sparing root replacement on the probability of postoperative aortic insufficiency and freedom from aortic valve reoperation. MethodsFrom 1995 to 2020, 177 patients underwent valve-sparing root replacement (163 reimplantations, 14 remodeling). Preoperative and postoperative echocardiograms were analyzed to measure annulus and sinus diameters, effective height of leaflet coaptation, and degree of aortic insufficiency. Logistic regression was used to evaluate predictors of 2+ or greater late postoperative aortic insufficiency. Fine-Gray regression determined predictors for aortic valve reintervention. ResultsThe study population included 122 (69%) men with a mean age of 43 ± 15 years. A total of 119 patients (67%) had an identified connective tissue disorder. The cumulative incidence of aortic valve reoperation was estimated as 7% at 5 years and 12% at 10 years. The probability of 2+ or greater late postoperative aortic insufficiency was inversely related to effective height during valve-sparing root replacement (P = .018). As postoperative effective height fell below 11 mm, the probability of 2+ or greater aortic insufficiency exceeded 10%. On multivariable logistic regression, effective height (odds ratio, 0.53; 0.33-0.86; P = .010), preoperative annulus diameter (odds ratio, 1.44; 1.13-1.82; P = .003), and degree of preoperative aortic insufficiency (odds ratio, 2.57; 1.45-4.52; P = .001) were associated with increased incidence of 2+ or greater late postoperative aortic insufficiency. On multivariable Fine-Gray regression, risk factors for aortic valve reintervention included preoperative annulus diameter (subdistribution hazard ratio, 1.28 [1.03-1.59], P = .027), history of 3+ or greater aortic insufficiency (subdistribution hazard ratio, 4.28; 1.60-11.44; P = .004), and 2+ or greater early postoperative aortic insufficiency (subdistribution hazard ratio, 5.22; 2.29-11.90; P < .001). ConclusionsMeasures to increase effective height during valve-sparing root replacement may decrease the risk of more than mild postoperative aortic insufficiency after repair and the need for aortic valve reoperation.

Management of cardiovascular manifestations in Loeys – Dietz syndrome: a systematic review

Ieva Daniliauskaitė1, Olivija Gustienė2 1 Faculty of Medicine, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania 2 Department of Cardiology, Lithuanian University of Health Sciences, Kaunas, Lithuania Abstract Loeys – Dietz syndrome (LDS) is an autosomal dominantly inherited genetic disorder associated with significant and often life-threatening cardiovascular damage. The major cause of death in these individuals is aortic dissection. The primary choice for both prophylactic and emergency surgical interventions remains aortic valve-sparing root replacement due to the lower incidence of complications and the need for reoperation. Also, open surgery is more often recommended than endovascular stenting due to the possible accelerated development of aortic aneurysm in the native aortic stent fixation zones. To date, there are no approved guidelines for the treatment of aortic aneurysm and dissection in patients with LDS, but it is well known that multidisciplinary management of this syndrome must involve cardiovascular surgeons, cardiologists and geneticists. Nevertheless, the current literature provides a number of treatment options and recommendations for LDS. Therefore, the purpose of this systematic literature review is to analyze and discuss treatment options for aortic injury in patients with LDS, including both prophylactic and emergency interventions. Keywords: Loeys – Dietz, aortic aneurysm, aortic dissection, management of aortic aneurysm.

Long-term durability of a reimplantationvalve-sparing aortic root replacement can be expected in both Marfan syndrome and Loeys-Dietz syndrome.

The goal of this study was to evaluate the surgical outcomes of a valve-sparing root replacement using the reimplantation technique for annuloaortic ectasia in patients with Marfan syndrome (MFS) and in those with Loeys-Dietz syndrome (LDS). We reviewed 103 patients with MSF with mutations in the fibrillin-1 gene and 28 patients with LDS with mutations in the transforming growth factor-beta receptor and 2, SMAD3 and transforming growth factor beta-2 from 1988 to 2020. Forty-four (42.7%) patients with MFS [26 men, 31 (7.6) years] and 10 (35.7%) patients with Loeys-Dietz syndrome (LDS) [7 men, 22 (standard deviation: 8.6) years] who had no aortic dissection and underwent valve-sparing root replacement were included. The preoperative sinus diameter [46 (45-50.5) mm in those with MFS vs 48 (47-50) mm in those with LDS, p = 0.420] and the percentage of aortic insufficiency > grade 2+ [31.8% (10/44) in patients with MFS vs 10.0% (1/10) in those with LDS, p = 0.667] revealed no significant differences between the 2 groups. The cumulative incidences of aortic insufficiency greater than grade 1 (p = 0.588) and aortic valve reoperation (p = 0.310) were comparable between the 2 groups. Patients with LDS had a higher tendency towards aortic dissection after the initial operation (p = 0.061) and a significantly higher cumulative incidence of aortic reoperation (p = 0.003) versus those with MFS. Patients with MFS and those with LDS showed similar cumulative incidences of recurrent aortic valve insufficiency and aortic valve reoperation. Those with LDS revealed a higher cumulative incidence of aortic reoperation and a greater tendency towards aortic dissection after the initial operation compared with those with MFS.

Valve-sparing aortic root replacement: a primer for cardiologists.

The purpose of this article is to review the contemporary evidence supporting valve-sparing aortic root replacement as the best option for patients with aortic root aneurysms and preservable aortic valves as well as to review the technical variations and modern adjuncts of these operations that impact both short and long-term durability. In patients with an aortic root aneurysm, with or without aortic valve regurgitation, valve-sparing aortic root replacement provide excellent clinical outcomes and stable valve function over several decades. Successful execution of this operation depends on careful patient selection and a thorough understanding of the anatomical and physiological relationships between the various components of the aortic root. Echocardiography remains the mainstay of imaging to determine the feasibility of valve-sparing root replacement. Valve-sparing aortic root replacement is an excellent alternative to composite valve graft replacement in nonelderly patients with aortic root aneurysms. Dedicated aortic root surgeons perform several technical variations of valve-sparing procedures aimed at matching the specific aortic root disorder with the optimal operation.

Outcomes of the Valve-Sparing Root Replacement Procedure with Partial Upper Sternotomy.

Due to better postoperative convalescence and quality of life, experienced centers focus on minimally invasive surgical techniques and approaches, but this approach is not routinely performed for valve-sparing root replacement procedures. The purpose of this study was to assess the safety and feasibility of valve-sparing root replacement via partial upper sternotomy. Between January 2016 and April 2021, 269 patients underwent a valve-sparing root replacement procedure, and partial upper sternotomy was performed in 52 patients. The clinical outcomes of the partial upper sternotomy (PUS) and complete sternotomy (CS) groups, including mortality, degree of aortic insufficiency, blood loss and consumption of blood products, postoperative complications, and hospitalization expenses, were compared. The Kaplan–Meier method was used to assess the degree of aortic regurgitation. Propensity score matching was performed as a sensitivity analysis. There was only one in-hospital death (in the CS group, p = 1) and no postoperative moderate to severe aortic insufficiency in either group. The blood loss and consumption of blood products in the PUS group were also lower than in the CS group, especially for plasma use. Regarding the need for re-exploration because of bleeding, acute kidney injury, pericardial pleural effusion, drainage volume within the first 24 h, mechanical ventilation time, and arrhythmia, the two groups were comparable. Patients in the CS group showed a longer ICU time (74.20 ± 47.21 vs. 50.9 30.16 h, p = 0.001) and higher hospitalization expenses (135,649.52 ± 29,992.21 vs. 123,380.15 ± 27,062.82 yuan, p < 0.001). None of the patients died or reoperated during the follow-up. Freedom from moderate or severe aortic insufficiency remained comparable after matching (p = 0.97). Minimally invasive valve-sparing aortic replacement via partial upper sternotomy can be safely performed in selected patients.

Outcomes of reoperative aortic root surgery

ObjectiveThe study objective was to determine the impact of reoperative aortic root replacement on short-term outcomes and survival. MethodsThis was a retrospective study of aortic root operations from 2010 to 2018. All patients with a complete aortic root replacement were included, and patients undergoing valve-sparing root replacements were excluded. Patients were dichotomized by first-time sternotomy versus redo sternotomy, which was defined as having had a prior sternotomy for whatever reason. Within the redo sternotomy group, reoperative aortic root replacements were identified, being defined as a complete aortic root replacement in patients with a prior aortic root replacement; 1:1 nearest neighbor propensity matching was used to compare outcomes across groups. Kaplan–Meier survival estimates were generated and compared using log-rank statistics. ResultsA total of 893 patients undergoing complete ARR were identified, of whom 595 (67%) underwent first-time sternotomy and 298 (33%) underwent redo sternotomy. After matching, postoperative outcomes were similar for the first-time and redo sternotomy groups, including operative mortality. Redo sternotomy was not associated with reduced survival after aortic root replacement compared with first-time sternotomy (P = .084), with 5-year survival of 73.7% for first-time sternotomy and 72.9% for redo sternotomy. In the redo sternotomy group (n = 298), 69 (23%) were reoperative aortic root replacements and 229 (77%) were first-time aortic root replacements. After matching, postoperative outcomes were similar for the first-time and reoperative aortic root replacement groups, including operative mortality. Reoperative aortic root replacement was not associated with reduced survival, compared with first-time aortic root replacement (P = .870), with 5-year survival of 67.9% for first-time aortic root replacement and 72.1% for reoperative aortic root replacement. ConclusionsReoperative aortic root replacement can be performed safely and provides similar survival to first-time aortic root replacement.

Florida sleeve is a safe and effective technique for valve salvage in acute stanford type A aortic dissection.

Valve-sparing root replacement is commonly used for management of aortic root aneurysms in elective setting, but its technical complexity hinders its broader adoption for acute type-A aortic dissection (ATAAD). The Florida sleeve (FS) procedure is a simplified form of valve sparing aortic root reconstruction that does not require coronary reimplantation. Here, we present our outcomes of the FS repair in patients with dilated roots in the setting of an ATAAD. We retrospectively reviewed 24 consecutive patients (2002-2018) treated with FS procedure for ATAAD. Demographic, operative, and postoperative outcomes were queried from our institutional database. Long term follow-up was obtained from clinic visits for local patients, and with telephone and telehealth measures otherwise. Mean age was 49 ± 14 years with 19 (79%) males. Marfan syndrome was present in 4 (16.7%) patients and 14 (58.3) had ≥2+ aortic insufficiency (AI). Nine (37.2%) had preoperative mal-perfusion or shock. The FS was combined with hemi-arch replacement in 15 (62.5%) patients and a zone-2 arch replacement in 9 (37.5%) patients. There were 2 (8.3%) early postoperative mortalities. Median follow-up period was 46 months (range, 0.3-146). The median survival of the entire cohort was 143.4 months. One patient (4.2%) required redo aortic valve replacement for unrelated aortic valve endocarditis at 30 months postoperatively. FS is simplified and reproducible valve-sparing root repair. In appropriate patients, it can be applied safely in acute Stanford type-A aortic dissection with excellent early and long-term results.

EVOLVING SURGICAL TECHNIQUES AND IMPROVING OUTCOMES FOR AORTIC ARCH SURGERY IN CANADA

BACKGROUND To explore evolving surgical techniques and outcomes for aortic arch surgery. METHODS AND RESULTS 2435 consecutive patients underwent aortic arch repair with hypothermic circulatory arrest between 2008 and 2018 in 12 institutions across Canada. Trends in patient characteristics, surgical techniques, and in-hospital outcomes including major morbidity or mortality (MMOM) were examined. From 2008-2018, age of patients (62.3yrs ± 13.2) and proportion of women (30.2%) undergoing arch surgery did not significantly change. Aortic diameters at operation decreased (2008: 58 ± 13mm, 2018: 53 ± 11mm; p < 0.01). Surgeons performed more valve-sparing root replacements (2008: 0%, 2018: 15%; p < 0.001) and fewer Bentall procedures (2008: 27%, 2018: 20%; p < 0.01). Total arch replacement rates were similar (p=0.18); however, elephant trunk (2008: 9.5%, 2018: 19%; p < 0.001) and frozen elephant trunk (2008: 3.1%, 2018: 15%; p < 0.001) repair rates have increased. Overtime, higher nadir temperatures (2008: 18[17-21]°C, 2018: 25[23-28]°C; p < 0.001), and more frequent antegrade cerebral perfusion (ACP) (2008: 61%, 2018: 83%; p < 0.001) were used. For elective cases, in-hospital mortality rates declined (2008: 6.8%, 2018: 1.2%; p= < 0.01), as did MMOM (2008: 24%, 2018: 13%; p < 0.001) and transfusion rates (2008: 61%, 2018: 41%; p < 0.001); but stroke rates remained constant (2008: 6.8%, 2018: 5.3% p=0.12).Outcomes remained the same over time for urgent or emergent cases. CONCLUSION Outcomes have improved over the last decade in Canada for elective aortic arch surgery, in the context of operating on smaller aortas, and more frequent use of moderate hypothermia and ACP. Further research is needed to improve stroke rates and outcomes in the emergency setting. To explore evolving surgical techniques and outcomes for aortic arch surgery. 2435 consecutive patients underwent aortic arch repair with hypothermic circulatory arrest between 2008 and 2018 in 12 institutions across Canada. Trends in patient characteristics, surgical techniques, and in-hospital outcomes including major morbidity or mortality (MMOM) were examined. From 2008-2018, age of patients (62.3yrs ± 13.2) and proportion of women (30.2%) undergoing arch surgery did not significantly change. Aortic diameters at operation decreased (2008: 58 ± 13mm, 2018: 53 ± 11mm; p < 0.01). Surgeons performed more valve-sparing root replacements (2008: 0%, 2018: 15%; p < 0.001) and fewer Bentall procedures (2008: 27%, 2018: 20%; p < 0.01). Total arch replacement rates were similar (p=0.18); however, elephant trunk (2008: 9.5%, 2018: 19%; p < 0.001) and frozen elephant trunk (2008: 3.1%, 2018: 15%; p < 0.001) repair rates have increased. Overtime, higher nadir temperatures (2008: 18[17-21]°C, 2018: 25[23-28]°C; p < 0.001), and more frequent antegrade cerebral perfusion (ACP) (2008: 61%, 2018: 83%; p < 0.001) were used. For elective cases, in-hospital mortality rates declined (2008: 6.8%, 2018: 1.2%; p= < 0.01), as did MMOM (2008: 24%, 2018: 13%; p < 0.001) and transfusion rates (2008: 61%, 2018: 41%; p < 0.001); but stroke rates remained constant (2008: 6.8%, 2018: 5.3% p=0.12).Outcomes remained the same over time for urgent or emergent cases. Outcomes have improved over the last decade in Canada for elective aortic arch surgery, in the context of operating on smaller aortas, and more frequent use of moderate hypothermia and ACP. Further research is needed to improve stroke rates and outcomes in the emergency setting.

Hemiarch replacement with aortic root preservation for acute type A aortic dissection

: Acute Type A aortic dissection (TAAD) is a surgical emergency requiring expeditious management. The surgical principles involve restoration of true lumen blood flow with obliteration of the primary tear thereby mitigating malperfusion and restoring valvular competency. At our institution 60% of TAAD patients are treated with a hemiarch and the other 40% are treated with a total arch replacement (TAR). All cases employ the use of cerebral protection. For hemiarch replacement, retrograde cerebral perfusion (RCP), via the superior vena cava (SVC), is utilized. Antegrade cerebral perfusion is utilized via brachiocephalic vessels during a TAR. Electroencephalogram (EEG) and somatosensory evoked potentials (SSEP) are used for neurocerebral monitoring with the aim of electrical silence before circulatory arrest. Key radiographic and clinical findings are used to adjudicate between these two procedures pre and intraoperatively. Patients with any of the following undergo a TAR at our institution: (I) aortic arch aneurysm, (II) primary or re-entry tear in the aortic arch or proximal descending aorta, (III) circumferential dissection of the aortic arch, or (IV) carotid body dissection or thrombosis. Irrespective of the procedure chosen, central aortic cannulation is routinely performed via modified Seldinger technique with transesophageal echocardiography guidance. The proximal aorta is addressed while the patient is systemically cooled to hypothermia. All effort is made to retain the native aortic root and valve where possible. However, in cases where the aortic root is dilated or has a tear, a valve sparing root replacement or a modified Bentall is performed. The operative strategy for a TAAD at our institution is predicated on a tear-based paradigm. However, the extent of aortic reconstruction may be different based on surgeon and center experience.

Valve sparing root replacement with the reimplantation technique in patients presenting with acute type A aortic dissections

: Patients presenting with acute type A aortic dissections (ATAAD) comprise an extremely heterogenous population. While a majority are older and suffer from chronic disease states, a non-insignificant minority are relatively healthy without long standing aneurysmal or aortic valve pathology. Selection of an appropriate proximal and distal operation can affect short- and long-term morbidity and mortality as well as the need for valve reintervention. In regard to management of the root, surgeons must be aggressive when indications for replacement—such as a sinus tear, aneurysmal degeneration, or friable tissue—are evident. In experienced centers, it is reasonable to proceed with a valve-sparing procedure in well selected patients. The risks and benefits of this decision must be considered carefully as a root replacement with either a biologic or mechanical prosthesis is preferred over a poorly executed valve sparing procedure. However, if the latter is approached in a standardized fashion with attention to the patient’s overall acuity, cardiac function, and aortic valve leaflet mobility, reproducible outcomes can and should be expected. Accordingly, we present our approach to valve sparing root replacement with the reimplantation technique in ATAAD. The following review includes a case-based discussion and video depiction of our technique, including safe and reliable cannulation methods for bypass, cerebral protection strategies, and a structured approach to critically appraise the valve prior to repair.

Bicuspid aortic valve repair: An ongoing struggle in material science.

Techniques and results of aortic valve repair remain challenging. Safari et al. seek to improve aortic valve repair by either aortic patching or valve sparing root replacement. The results of bicuspid aortic valve (BAV) repair in 142 patients were examined withor without valve sparing root replacement. Isolated BAV repair with or without valve sparing root replacement provided goodclinical outcomes with relatively low reoperation rate and durable valve function. While clinical outcome from BAV repair was generally good, the authors have stopped pericardial patch augmentation of BAV leaflets due to suboptimal durability. Thelack of a durable valve patch material and the modest durability of BAV repairin general point out that aortic valve repair remains an ongoing struggle inmaterial science.