Aortic Root Replacement With Biological Valved Conduits

Mechanical Versus Bioprosthetic Aortic Valve Replacement in Patients Undergoing Bentall Procedure

BACKGROUND

The widely used Bentall procedure is the criterion standard treatment for aortic root pathology. Studies comparing the long-term outcomes of bioprosthetic and mechanical valves in patients undergoing the Bentall procedure are limited.

METHODS AND RESULTS

Patients who underwent the Bentall procedure with a bioprosthetic or mechanical valve between 2001 and 2018 were identified from Taiwan's National Health Insurance Research Database. The primary outcome of interest was all-cause mortality. Inverse probability of treatment weighting was performed to compare the 2 prosthetic types. In total, 1052 patients who underwent the Bentall procedure were identified. Among these patients, 351 (33.4%) and 701 (66.6%) chose bioprosthetic and mechanical valves, respectively. After inverse probability of treatment weighting, no significant differences in the in-hospital mortality (odds ratio, 0.96 [95% CI, 0.77-1.19]; P=0.716) and all-cause mortality (34.1% vs. 38.1%; hazard ratio, 0.90 [95% CI, 0.78-1.04]; P=0.154) were observed between the groups. The benefits of relative mortality associated with mechanical valves were apparent in younger patients and persisted until ≈50 years of age.

CONCLUSIONS

No differences in survival benefits were observed between the valves in patients who underwent the Bentall procedure. Additionally, bioprosthetic valves may be a reasonable choice for patients aged >50 years when receiving the Bentall procedure in this valve-in-valve era.

Aortic Root Surgery in Adults: An Unsolved Problem

Nowadays, despite the rapid advancements in interventional cardiology, open surgery still deals with aortic root diseases, to assure the best "ad hoc" treatment. In case of middle-aged adult patients, the optimal operation still represents a matter of debate. A review of the last 10-year literature was conducted, focusing on patients below 65 to 70 years of age. Because of the small sample and the heterogeneity of the papers, no metanalysis was possible. Bentall-de Bono procedure, valve sparing, and Ross operations are the surgical options currently available. The main issues in the Bentall - de Bono operation are lifelong anticoagulation therapy and cavitation in case of mechanical prosthesis implantation and structural valve degeneration in case of biological Bentall. As transcatheter procedures are currently performed as valve in valve, biological prosthesis may be preferable, if the diameter may prevent postoperative high gradients. Conservative techniques, such as remodeling and reimplantation, preferred in the young, guarantee physiologic aortic root dynamics and impose surgical analysis of the aortic root structures to get a durable result. The Ross operation, which shows excellent performance, involves autologous pulmonary valve implantation and is performed only in experienced and high-volume centers. Due to its technical difficulty, it requires a steep learning curve and presents some limitations in specific aortic valve diseases. All three have advantages and downsides, and no ideal solution has still been reported.

Bentall Operation: Early Surgical Results, Seven-Year Outcomes, and Risk Factors Analysis

Aim: To analyze early and mid-term outcomes of the Bentall operation. Methods: Two hundred and seventeen patients (mean age 65.6 ± 15.9 years, males/females 172/45) underwent Bentall operation in a 7-year period (January 2015−December 2021), on average, 30 Bentall operations occurred per year, using biological (n = 104) or mechanical (n = 113) valved conduits for the treatment of ascending aorta−aortic root aneurysms. Associate procedures were performed in 58 patients (26.7%); coronary artery bypass grafting (CABG) in 35 (16%). Mean follow-up was 55.2 ± 24 (median 60.2) months. Cox model analysis was used to assess risk factors, Kaplan−Meier and log-rank tests were used to assess different survival rates. Results: Operative mortality was 1.38%. At 7 years, survival, freedom from cardiac death, and event-free survival were 93% ± 2%, 99% ± 1%, and 81% ± 5%. NYHA class (p < 0.0001), trans-aortic valve mean (p < 0.0001) and maximum (p < 0.000) gradients, left ventricular hypertrophy (p < 0.05), and pulmonary arterial pressure (p = 0.002) significantly improved vs. preoperative values. Concomitant CABG during Bentall operation independently affected late outcomes (HR 1.9−2.3; p-values < 0.05). Late survival was affected by concomitant CABG (84% ± 8% vs. 95% ± 2%, p = 0.04), preoperative myocardial infarction (91% ± 9% vs. 97% ± 2%, p = 0.02), and biological vs. mechanical prostheses valved conduits (91% ± 9% vs. 95% ± 3%, p = 0.02). Event-free survival also was affected by concomitant CABG (62% ± 14% vs. 85% ± 5%, p = 0.005) and biological prostheses (78% ± 8% vs. 84% ± 6%, p = 0.06). Freedom from endocarditis−redo operation was 83% ± 9% for biological prostheses vs. 89% ± 6% for mechanical prostheses (p = 0.49). Conclusions: Low rates of operative mortality and late complications make Bentall operation the gold standard for the treatment of ascending aorta−aortic root aneurysms. Coronary ischemic disease affects late outcomes. Biological prostheses should be preferred for the elderly.

Clinical Outcomes Using Freestyle Valve/Valsalva Graft Composite Conduit for Aortic Root Replacement

BACKGROUND

We review the clinical outcomes with a novel method of aortic root replacement using a self-constructed tissue valve-conduit comprised of a Freestyle subcoronary valve sewn into a Valsalva graft.

METHODS

From 2005 to 2020, 523 patients had aortic root replacement operations using a self-constructed Freestyle Subcoronary-Valsalva graft tissue valve-conduit. Median age was 62 years (IQR 54-70) and 430 (82%) were male patients. Primary outcomes were mortality and the need for reoperation. Multivariable regression analyses were performed to identify risk factors for mortality and reoperation.

RESULTS

Urgent procedures comprised 48.37% of the cases and 29.26% were reoperative procedures. Concomitant ascending aorta replacement, hemi-arch replacement, and total arch replacement were required in 348 (67%), 227 (44%), and 40 (8%) patients, respectively. Cardiopulmonary bypass and cross-clamp times were 189 minutes (IQR 164-218) and 166 minutes (IQR 145-191). Early mortality was 7.7% (40), five and ten-year survival was 83% and 71% respectively. At last echo follow-up, LVEF, LV end diastolic diameter, degree of AI, and mean aortic valve gradient were significantly improved from baseline, p<0.001. Increasing age, peripheral artery disease, tobacco use, increased preoperative creatinine, and prior aortic valve surgery were risk factors for both mortality and the composite outcome (p<0.02).

CONCLUSIONS

In a complex patient population, aortic root replacement using a self-constructed composite tissue valve-conduit comprised of a Freestyle Subcoronary Valve/Valsalva Graft can be performed with excellent operative and 10-year outcomes. Mid-term survival is acceptable and valve durability was outstanding with an exceedingly low incidence for valve reintervention.

Long-term results of modified bentall procedures: 18-year experience of the flanged technique

OBJECTIVES

To evaluate the early and late outcomes of the modified Bentall procedure with the flanged technique.

METHODS

We reviewed the medical records of 63 patients who had undergone root replacement by the modified Bentall procedure at our institute between January 2001 and December 2018. In most cases, we adopted a composite graft constructed with a mechanical valve or bioprosthesis and a Dacron graft by the flanged technique. Since 2011, we have used Valsalva grafts.

RESULTS

Mean age 57 ± 16 years, range 16-80, male 43 cases. The mean follow-up was 75 ± 56 months (range 0-216). Through April 1, 2020, we could follow up on 61 cases (97%) within a six-month period. Hospital mortality was 7.9% (4.8% in elective cases). In late follow-up, eight deaths were observed. In the bio-Bentall group (n=26), no deaths or major adverse valve-related events (MARVEs) occurred. In the mechanical Bentall group (n=37), seven cases of MARVEs, including two cerebral hemorrhages and one cerebral embolism, were observed. All patients were free from MARVEs at 5 years post procedure in the bio-Bentall group, and 93.8% and 76.8% were event-free at 5 years and 10 years, respectively, in the mechanical Bentall group.

CONCLUSIONS

The 18-year results of the modified Bentall procedure were acceptable, providing excellent outcomes in the bio-Bentall group. The flanged technique enabled the use of a larger prosthesis, which may have resulted in good durability with the bio-Bentall procedure.

Incidence, Cause, and Outcome of Reinterventions after Aortic Root Replacement

BACKGROUND

This study aims to comprehensively characterize the details of the aortic and aortic valve reinterventions after aortic root replacement (ARR).

METHODS

Between 2005 and 2019, 882 patients underwent ARR. The indication was for aneurysm in 666, aortic valve-related in 116, aortic dissection in 64, and infective endocarditis (IE) in 36. Valve-sparing root replacement was performed in 290 while Bio-Bentall was done in 528. Among them, 52 (5.9%) patients required reintervention. The incidence, cause, and time to reintervention, as well as outcomes after reintervention were investigated. Cause-Specific Cox hazard model was performed to identify predictors for reintervention after ARR.

RESULTS

The 10-year cumulative incidence of aortic and aortic valve reintervention after ARR was 10.3% [95%CI, 7.3%-14.0%]. Age per year decrease was the only independent predictor for reintervention [sHR, 0.97; 95%CI, 0.95-0.99]. The causes for 52 reinterventions were: 29 (55.8%) for aortic valve causes including aortic stenosis/insufficiency, and prosthetic valve dysfunction; 15 (28.9%) for IE; 7 (13.5%) for aortic-related causes including pseudoaneurysm, development of aneurysm, and residual dissection; and 1 (1.9%) for coronary button pseudoaneurysm. Median times to reintervention were 11.0 [IQR, 2.0-20.5] months for IE, 24.0 [IQR, 3.7-46.1] months for aortic-related causes, 77.0 [IQR, 28.4-97.6] months for aortic valve-related causes (p=.005). Overall in-hospital mortality after the reinterventions was 7.7% (4/52) with 20.0% with IE (3/15) .

CONCLUSIONS

Reintervention for IE occurs relatively early after ARR while aortic valve- and aortic-related reinterventions gradually increase over time. In-hospital mortality after the reintervention is low, unless it is for IE.

Bicuspid-Associated Aortic Root Aneurysm: Mid to Long-Term Outcomes of David V Versus the Bio-Bentall Procedure

David V valve-sparing root replacement (VSRR) and bio-Bentall (BB) are increasingly performed for aortic root aneurysms associated with a bicuspid aortic valve (BAV). However, durability remains a concern in both procedures. We compared the 10-year outcomes of VSRR vs BB for BAV-associated root aneurysms. A retrospective review identified 134 patients with a BAV-associated root aneurysm who underwent VSRR (n = 65) or BB (n = 69) from 2005 to 2019. Patients with aortic stenosis, endocarditis, previous aortic valve replacement, and emergent cases were excluded. Propensity-score matching was performed, resulting in 2 risk-adjusted groups (n = 40 per group). Median follow-up was 6.21 (1.43-8.28) years. The VSRR cohort was younger (46.0 years vs 56.0 years, P < 0.001) and had a lower incidence of at least moderate aortic insufficiency (AI) (78.5% vs 92.8%, P = 0.02). The incidence of Marfan syndrome, aortic root diameter, and ascending aortic diameter were similar. In-hospital mortality was 1.5% (n = 1) and 1.4% (n = 1) for VSRR and BB, respectively. There was no difference between VSRR and BB in 10-year survival (98.3% [95% confidence interval (CI): 88.6-99.8%] vs 96.2% [95% CI: 85.5-99.0%], P = 0.567) and aortic valve reintervention at 10 years (16.1% [95% CI: 6.3-29.8%] vs 12.9% [95% CI: 3.7-28.0%], P = 0.309). The most common reason for valve reintervention in both groups was AI. Survival and valve reintervention at 10 years were similar in the matched cohort. David V VSRR yields similar mid to long-term outcomes to BB for select patients with a BAV-associated aortic root aneurysm in regards to survival and reintervention rates. Further studies comparing longer term outcomes between root replacement techniques and native valve durability are needed.

Long-term follow-up of Bentall procedure using the Perimount bioprosthesis and the Valsalva graft

OBJECTIVES

Bentall procedure is the gold standard for aortic root pathologies when valve repair is not feasible. The development of durable bioprosthetic valves and improved vascular conduits allowed the implementation of bioprosthetic composite grafts; hereby, we performed a retrospective analysis of long-term follow-up of Bentall procedure using the Valsalva graft and the Perimount Magna Ease prosthesis.

METHODS

From June 2000 to March 2019, 309 patients received an aortic root and valve replacement with a bioprosthetic composite graft. The mean age was 69 ± 6.9 years, and the majority were men (88%); most of them were affected by aortic stenosis (86%) and the mean aortic root diameter was 48.6 ± 5.5 mm.

RESULTS

Freedom from cardiac death was 76.8% [confidence interval (CI) 32.5-94.0] at 16 years. Freedom from thromboembolism, haemorrhage, structural valve deterioration and infective endocarditis was 98.2% (CI 96.0-98.9), 95.2% (CI 87.1-98.2), 87.5% (CI 63.2-97.1) and 79.6% (CI 45.3-95.6) at 16 years, respectively. Freedom from reoperation was 74.7% (CI 41.9-90.6).

CONCLUSIONS

These data indicate that, in experienced centres, the Bentall procedure is a safe and effective intervention. This is the first long-term follow-up that analyses the results after implantation of a composite graft made with the Perimount Magna Ease aortic valve and the Valsalva graft.

Biological solutions to aortic root replacement: valve-sparing versus bioprosthetic conduit‡

OBJECTIVES

Valve-sparing operations and root replacement with a biologic composite conduit are viable options in aortic root aneurysm. This study was conceived to compare the early and mid-term results of these 2 procedures.

METHODS

From September 2002 to November 2015, 749 consecutive patients underwent either a valve-sparing operation or a root replacement with a biologic composite conduit at 2 institutions. Propensity score matching was used to compare similar cohorts of patients in the overall population and in the ≤ 55 and ≥ 65-year age groups.

RESULTS

Overall operative mortality was 0.4%, mean age 57.4 ± 14.3 years, 84.6% were male. Individuals in the biologic composite conduit group were older and had worse preoperative risk profiles [chronic pulmonary disease (5.5% vs 0.9%; P  = 0.001), diabetes (6.4% vs 1.5%; P  = 0.001) and NYHA > 2 (25.2% vs 5.2%; P  < 0.001)]. Mean follow-up was 27.5 ± 28.4 months. In the unmatched population, there was no difference in in-hospital deaths (0 in the valve-sparing versus 3 in the biologic composite conduit group; P  = 0.12). These findings were confirmed in the propensity-matched populations. During follow-up, more patients in the biologic composite conduit group underwent reoperation on the aortic valve (2.6% vs 1.5%; P  = 0.026) resulting in a freedom from reoperation of 97.4% vs 98.5%, respectively. Separate analysis for patients stratified by age revealed no difference in outcomes.

CONCLUSIONS

In case of aortic root aneurysm, both valve-sparing operations and root replacement with a biologic composite conduit provide excellent outcomes. However, at mid-term follow-up the use of biologic composite conduit is associated with a higher risk of reoperation.

The Aortic Root: Natural History After Root-Sparing Ascending Replacement in Nonsyndromic Aneurysmal Patients

BACKGROUND

Leaving native aortic tissue in situ in root-sparing ascending aortic replacement raises concern regarding potential later need for root reoperation or for the potential occurrence of localized dissections or rupture in the residual root. The purpose of this study was to evaluate the natural growth of the aortic root after root-sparing aortic replacement.

METHODS

In all, 102 consecutive patients (mean age 61.8 ± 12.5 years; 60% male) who had undergone root-sparing aortic replacement had sufficient retrievable information regarding their aortic root diameter at postoperative baseline and follow-up imaging by computed tomography or echocardiography. The annual growth rate was evaluated and also compared according to the influence of valve morphology and concomitant aortic valve replacement. Furthermore, the years of natural history that would require for root enlargement to meet a 50 mm threshold of the root diameter were calculated.

RESULTS

The estimated growth rate of the aortic root after root-sparing aortic replacement is between 0.27 and 0.51 mm per year (mean 0.41 mm, varying according to the underlying diameter) and therefore fivefold less than other aortic regions. Accordingly, a root aneurysm indicating reoperation would not be expected for 29.1 years on average. Only patients with a diameter of 45 mm or more are at risk for reoperation, and not until at least after 10.4 years have passed. Neither the valve morphology (p = 0.62) nor concomitant aortic valve replacement (p = 0.86) influenced rate of root dilation.

CONCLUSIONS

In nonsyndromic patients, the aortic root is the slowest growing portion of the thoracic aorta. Leaving the native root, as in root-sparing ascending aortic replacement, is a safe approach regarding secondary root intervention for aortic root diameters of 45 mm or less.

Aortic valve disease with ascending aortic aneurysm: Impact of concomitant root-sparing (supracoronary) aortic replacement in nonsyndromic patients

OBJECTIVE

The purpose of the study was to assess the anticipated incremental risk of a concomitant aortic resection performed with an aortic valve replacement.

METHODS

Patients who underwent aortic valve replacement with root-sparing ascending replacement were compared with those who underwent isolated aortic valve replacement using propensity score matching (81 pairs; mean age, 63 ± 11 years [root-sparing ascending replacement] vs 64 ± 14 years). To evaluate the impact of the technique at distal site, 71 pairs of those undergoing root-sparing ascending replacement also were matched by propensity score according to distal anastomosis performed clamped and open under deep hypothermic circulatory arrest.

RESULTS

Operative mortality was equal between the root-sparing ascending replacement and isolated aortic valve replacement groups. No significant difference was found regarding postoperative morbidities, such as bleeding, renal failure, stroke, and length of stay, except prolonged ventilation was found after root-sparing procedures (P = .028). Survival estimation showed no difference between the groups. Comparing the patients undergoing root-sparing ascending replacement with clamped and opened distal anastomosis revealed a prolonged ventilation requirement (7% vs 3%; P = not significant) in the open group. Operative mortality was 0% in both groups, and midterm survival was comparable.

CONCLUSIONS

The concomitant replacement of the aorta in root-sparing fashion is associated with an excellent operative outcome and adds no additional risk to aortic valve replacement in elective and non-high-risk patients. If the distal anastomosis is performed in an open fashion, while the operative mortality is still very low, morbidities are slightly higher, but midterm survival remains comparable.