Results of aortic valve-sparing operations

Restoration of flow in the aorta: a novel therapeutic target in aortic valve intervention

Aortic blood flow patterns are closely linked to the morphology and function of the left ventricle, aortic valve and aorta. These flow patterns demonstrate the exceptional adaptability of the cardiovascular system to maintain blood circulation under a broad range of haemodynamic workloads and can be altered in various pathophysiological states. For instance, normal ascending aortic systolic flow is predominantly laminar, whereas abnormal aortic systolic flow is associated with increased eccentricity, vorticity and flow reversal. These flow abnormalities result in reduced aortic conduit function and increased energy loss in the cardiovascular system. Emerging evidence details the association of these flow patterns with loss of aortic compliance, which leads to adverse left ventricular remodelling, poor tissue perfusion, and an increased risk of morbidity and death. In this Perspective article, we review the evidence for the link between aortic flow-related abnormalities and cardiovascular disease and how these changes in aortic flow patterns are emerging as a therapeutic target for aortic valve intervention in first-in-human studies.

Aortic Root Replacement Surgery—A Center Experience with Biological Valve Prostheses

Objective: Outcomes after surgical aortic root replacement using different valved conduits are rarely reported. The present study shows the experience of a single center with the use of the partially biological LABCOR (LC) conduit and the fully biological BioIntegral (BI) conduit. Special attention was paid to preoperative endocarditis. Methods: All 266 patients who underwent aortic root replacement by an LC conduit (n = 193) or a BI conduit (n = 73) between 01/01/2014 and 31/12/2020 were studied retrospectively. Dependency on an extracorporeal life support system preoperatively and congenital heart disease were exclusion criteria. For patients with (n = 67) and without (n = 199) preoperative endocarditis subanalyses were made. Results: Patients treated with a BI conduit were more likely to have diabetes mellitus (21.9 vs. 6.7%, p < 0.001), previous cardiac surgery (86.3 vs. 16.6%; p < 0.001), permanent pacemaker (21.9 vs. 2.1%; p < 0.001), and had a higher EuroSCORE II (14.9 vs. 4.1%; p < 0.001). The BI conduit was used more frequently for prosthetic endocarditis (75.3 vs. 3.6%; <0.001), and the LC conduit was used predominantly for ascending aortic aneurysms (80.3 vs. 41.1%; <0.001) and Stanford type A aortic dissections (24.9 vs. 9.6%; p = 0.006). The LC conduit was used more often for elective (61.7 vs. 47.9%; p = 0.043) and emergency (27.5 vs. 15.1%; p = 0–035) surgeries, and the BI conduit for urgent surgeries (37.0 vs. 10.9%; p < 0.001). Conduit sizes did not differ significantly, with a median of 25 mm in each case. Surgical times were longer in the BI group. In the LC group, coronary artery bypass grafting and proximal or total replacement of the aortic arch were combined more frequently, whereas in the BI group, partial replacement of the aortic arch were combined. In the BI group, ICU length of stay and duration of ventilation were longer, and rates of tracheostomy and atrioventricular block, pacemaker dependence, dialysis, and 30-day mortality were higher. Atrial fibrillation occurred more frequently in the LC group. Follow-up time was longer and rates of stroke and cardiac death were less frequent in the LC group. Postoperative echocardiographic findings at follow-up were not significantly different between conduits. Survival of LC patients was better than that of BI patients. In the subanalysis of patients with preoperative endocarditis, significant differences between the used conduits were found with respect to previous cardiac surgery, EuroSCORE II, aortic valve and prosthesis endocarditis, elective operation, duration of operation, and proximal aortic arch replacement. For patients without preoperative endocarditis, significant differences were observed concerning previous cardiac surgery, pacemaker implantation history, duration of procedure, and bypass time. The Kaplan–Meier curves for the subanalyses showed no significant differences between the used conduits. Conclusions: Both biological conduits studied here are equally suitable in principle for complete replacement of the aortic root in all aortic root pathologies. The BI conduit is often used in bail-out situations, especially in severe endocarditis, without being able to show a clinical advantage over the LC conduit in this context.

CT of Postoperative Repair of the Ascending Aorta and Aortic Arch

While many of the classic open surgical repairs are still used to repair the ascending aorta, management of the aortic arch has become more complex via implementation of newer open surgical and endovascular techniques. Furthermore, techniques are often combined in novel repairs or to allow extended anatomic coverage. As such, a framework that rests on understanding the expected postoperative appearance is necessary for the diagnostic radiologist to best interpret CT studies in these patients. After reviewing the imaging appearances of the common components used in proximal aortic repair, the authors present a structured approach that focuses on the key relevant questions that diagnostic radiologists should consider when interpreting CT studies in these patients. For repair of the ascending aorta, this includes determining whether the aortic valve has been repaired, whether the sinuses of Valsalva have been repaired, and how the coronary arteries were managed, when necessary. In repairs that involve the aortic arch, the relevant considerations relate to management of the arch vessels and the distal extent of the repair. In focusing on these questions, the diagnostic radiologist will be able to identify and describe the vast majority of repairs. Understanding these questions will also facilitate improved understanding of novel repairs, which often use these basic building blocks. Finally, complications-which typically involve infection, noninfectious repair breakdown, hemorrhage, problems with endografts, or disease of the remaining adjacent aorta-will be identifiable as deviations from the expected postoperative appearance. Online supplemental material is available for this article. ^©RSNA, 2021.

Aortic root replacement with Medtronic Freestyle bioprosthesis: 25-year experience

BACKGROUND

Stentless porcine bioprothesis is a surgical strategy to treat aortic root disease. Use has been limited due to the concern for long-term valve degeneration. This study evaluated the perioperative and late outcomes of patients with aortic root disease requiring root replacement.

METHODS

A total of 409 patients underwent aortic root replacement by a single surgeon using a stentless porcine bioroot between February 1996 and May 2020. The cohort was divided into two groups (age ≤65 and >65 years). Descriptive statistics were used to analyze the data and Kaplan-Meier curves used to evaluate long-term outcomes.

RESULTS

Patients age >65 years were more likely to be female (p = .01), have hypertension (p = .01), require circulatory arrest (p = .01), and have concomitant coronary artery bypass grafting (CABG) (p = .04). Baseline creatinine >1.8 (p = .20), diabetes (p = .06), and ejection fraction (p = .20) were similar between groups. The 1-, 5-, and 10-year survival for patients age ≤65 years were 92%, 87%, and 69%, respectively, significantly better than patients age >65 (88%, 73%, and 43%, respectively) (p < .01, Figure 1). The 1-, 5-, and 10-year freedom from reoperation for patients ≤65 years were 99%, 97%, and 93% versus 99%, 98%, and 96% in patients age >65 years, respectively (p = .24).

CONCLUSION

Patients with aortic root disease can be treated with acceptable perioperative outcomes, long-term survival, and low reoperation rates using a stentless porcine bioprothesis. It should be considered irrespective of age due to its excellent durability and freedom from anti-coagulation requirement.

Comprehensive Ex Vivo Comparison of 5 Clinically Used Conduit Configurations for Valve-Sparing Aortic Root Replacement Using a 3-Dimensional-Printed Heart Simulator

Supplemental Digital Content is available in the text.

Background:

Many graft configurations are clinically used for valve-sparing aortic root replacement, some specifically focused on recapitulating neosinus geometry. However, the specific impact of such neosinuses on valvular and root biomechanics and the potential influence on long-term durability are unknown.

Methods:

Using a custom 3-dimenstional–printed heart simulator with porcine aortic roots (n=5), the anticommissural plication, Stanford modification, straight graft (SG), Uni-Graft, and Valsalva graft configurations were tested in series using an incomplete counterbalanced measures design, with the native root as a control, to mitigate ordering effects. Hemodynamic and videometric data were analyzed using linear models with conduit as the fixed effect of interest and valve as a fixed nuisance effect with post hoc pairwise testing using Tukey’s correction.

Results:

Hemodynamics were clinically similar between grafts and control aortic roots. Regurgitant fraction varied between grafts, with SG and Uni-Graft groups having the lowest regurgitant fractions and anticommissural plication having the highest. Root distensibility was significantly lower in SG versus both control roots and all other grafts aside from the Stanford modification (P≤0.01 for each). All grafts except SG had significantly higher cusp opening velocities versus native roots (P<0.01 for each). Relative cusp opening forces were similar between SG, Uni-Graft, and control groups, whereas anticommissural plication, Stanford modification, and Valsalva grafts had significantly higher opening forces versus controls (P<0.01). Cusp closing velocities were similar between native roots and the SG group, and were significantly lower than observed in the other conduits (P≤0.01 for each). Only SG and Uni-Graft groups experienced relative cusp closing forces approaching that of the native root, whereas relative forces were >5-fold higher in the anticommissural plication, Stanford modification, and Valsalva graft groups.

Conclusions:

In this ex vivo modeling system, clinically used valve-sparing aortic root replacement conduit configurations have comparable hemodynamics but differ in biomechanical performance, with the straight graft most closely recapitulating native aortic root biomechanics.

Extensive aortic surgery in acute aortic dissection type A on outcome - insights from 25 years single center experience

BACKGROUND

This single center study compares the different surgical techniques used in the treatment of acute aortic dissection type A (AADA) analyzing the influence of the extent of the surgical approach on outcome.

METHODS

From 1988 to 2012, 407 patients were operated for AADA. The cohort was divided into subgroups according to the surgical approach. These groups were compared with the supracommissural replacement group (SCR; n = 141). Groups included aortic valve sparing techniques (AVS; n = 29), Composite replacement (COMP; n = 119), COMP with total arch replacement (COMP+TAR; n = 27) and SCR with TAR (n = 75).

RESULTS

Compared to SCR alone, operation (p = 0.005), bypass-, cross-clamp and circulatory arrest times were longer in SCR + TAR (all p < 0.001). Moreover, operation, bypass and cross clamp times were longer in COMP+TAR (p = 0.003, p = 0.002 and p < 0.001 respectively). COMP alone and AVS required longer cross-clamp time, too (p < 0,001 and p = 0.002, respectively). Overall 30-day mortality was 21% with the observed lowest rate after AVS (14%, SCR 18%, COMP 25%) but differences in 30-day mortality were not statistically significant. The estimated 10-year survival was 42%, especially AVS demonstrated a good 10-year survival (69%). David technique was superior to Yacoub technique concerning incidence of redo interventions (p = 0.036). Risk factors for early mortality included age, circulatory arrest, general malperfusion, bypass and operation time. Circulatory arrest per se was revealed as risk factor for long-term survival.

CONCLUSIONS

Within our single center retrospective study concomitant aortic root repair or aortic arch replacement for AADA demonstrated acceptable early and long-term survival. Circulatory arrest, long bypass and operation times per se might be important risk factors for early mortality. AVS techniques can be performed safely and have good outcomes in acute aortic dissection repair.

The Florida Sleeve Procedure Is Durable and Improves Aortic Valve Function

Background  The Florida (FL) Sleeve procedure was introduced as a simplified approach for valve-sparing correction of functional Type I aortic insufficiency (AI) associated with aortic root aneurysms. In this study, short- and long-term outcomes after the FL Sleeve procedure were investigated.

Methods  From May 2002 to January 2016, 177 patients underwent the FL Sleeve procedure. Left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter, left ventricular ejection fraction, and degree of AI (none = 0, minimal = 1, mild = 2, moderate = 3, severe = 4) were evaluated by echocardiography.

Results  Mean ± standard deviation of age was 49.41 ± 15.37 years. Survival rate was 98% at 1 year, 97% at 5 years, and 93% at 8 years. Freedom from reoperation was 99% at 1 year and 98% at 2 to 8 years. Three patients (1.69%) died during hospitalization. Three patients (1.69%) developed periprocedural stroke. Postoperative follow-up echocardiography was available in 140 patients at 30 days, and 31 patients at 5 years. AI grade significantly improved from baseline at 30 days (2.18 ± 1.26 vs. 1.1 ± 0.93, p  < 0.001) and at 5 years (2.0 ± 1.23 vs. 1.45 ± 0.88, p  = 0.04). Preoperative mean LVEDD significantly decreased from 52.20 ± 6.73 to 46.87 ± 8.40 ( p  < 0.001) at 30 days, and from 53.22 ± 7.07 to 46.61 ± 10.51 ( p  = 0.01) at 5 years.

Conclusions  The FL Sleeve procedure is a safe, effective, and durable treatment of aortic root aneurysm and Type I AI. Long-term survival and freedom from reoperation rates are encouraging.

Aortic Valve-Sparing Root Replacement (David I Procedure) in Adolescents: Long-Term Outcome

INTRODUCTION

Aortic valve-sparing root replacement (David's procedure) is an especially appealing treatment option for young patients. Here, we present the short-, mid, and long-term outcomes of this operation in adolescent patients.

METHODS

Between September 1994 and March 2014, 29 patients aged 6 to 21 years underwent the David-I procedure at our center. We conducted a retrospective study with follow-up.

RESULTS

The mean age was 16.8 ± 3.4 years and 90% (n = 26) were male. Marfan's syndrome was present in 86% (n = 25) of cases. Ninety-seven percent (n = 28) of cases were performed electively, and one case (3%) was performed emergently for acute aortic dissection type A. There were no early perioperative deaths (0%). Follow-up, which was completed on 100% of patients, comprised a total of 394 patient years and a mean follow-up time of 13.6 ± 5.4 years. The estimates for survival at 1, 5, and 10 years after initial surgery were 100, 97, and 93%, respectively. During follow-up, there were four (14%) late deaths and five (17%) aortic valve-related reoperations. The 1-, 5-, and 10-year estimates for freedom from valve-related reoperation were 100, 86, and 83%, respectively. The perioperative mortality for these five reoperations was 0%.

DISCUSSION

Aortic valve-sparing root replacement can be performed in adolescents with a very low perioperative risk. Long-term survival seems to be affected by connective tissue diseases.

Stanford type A aortic dissection in a patient with Marfan syndrome during pregnancy: a case report

Aortic dissection during pregnancy is a devastating event for both the pregnant woman and the baby. We report a case of acute aortic dissection (Stanford type A) in a pregnant woman with Marfan syndrome at the 29^th week of gestation. She underwent a cesarean section followed by an ascending aorta and total arch replacement with cardiopulmonary bypass, without a prior sternotomy. The hemodynamic parameters were kept stable during the cesarean section by using inotropes and vasopressors under transesophageal echocardiography monitoring. The newborn survived after endotracheal intubation and management in a neonatal intensive care unit.

Residual and Progressive Aortic Regurgitation After Valve-Sparing Root Replacement: A Propensity-Matched Multi-Institutional Analysis in 764 Patients

BACKGROUND

Residual/progressive aortic regurgitation (rAR, pAR) after valve-sparing aortic root replacement (V-SARR) can lead to reoperations. We sought to characterize risk factors of mild rAR and pAR after V-SARR in a multicenter cohort. The effect of additional cusp repair on valve function was analyzed using propensity matching.

METHODS

A total of 1,015 patients after V-SARR were identified with (n = 288, 28%) or without additional cusp/commissure repair (n = 727, 72%) at four cardiac units in Germany. A total of 764 patients fulfilling transthoracic echocardiography follow-up-criteria comprised the study cohort. Logistic regression was used for risk factor analysis with endpoints rAR, new onset AR, and pAR. t tests and analyses of variance were used for between-group differences. The effects of additional cusp repair on valve function were studied comparing propensity-matched quintiles.

RESULTS

The incidence of rAR was 29%, with influencing factors aneurysm size (p = 0.07) and preoperative aortic valve function (p = 0.08). It was found more often among nonsyndromic patients (34% vs. 14%; OR, 0.4; p < 0.001). Progression of rAR was detectable in 30% after a mean of 4.3 years. The progression rate of rAR ∼ 0.3 grades per patient-year within the first 5 years. When quintiles identified by propensity score were compared, additional cusp repair was linked to new onset AR (p = 0.016) while it was not linked to rAR (p = 0.14) or pAR (p = 0.5).

CONCLUSIONS

The incidences of rAR and pAR are considerable after V-SARR. Patients should be operated on before large aneurysms are present. New onset AR after an initially good functional result is more likely after an additional cusp repair, while rAR and pAR are not influenced by cusp repair.

Comparison of Hemodynamics After Aortic Root Replacement Using Valve-Sparing or Bioprosthetic Valved Conduit

BACKGROUND

The purpose of this study is to compare aortic hemodynamics and blood flow patterns using in-vivo four-dimensional (4D) flow magnetic resonance imaging (MRI) in patients after valve-sparing aortic root replacement (VSARR) and aortic root replacement with bioprosthetic valves (BIO-ARR).

METHODS

In-vivo 4D flow MRI was performed in 11 patients after VSARR (47 ± 18 years, 6 bicuspid aortic valves, 5 trileaflet aortic valves), 16 patients after BIO-ARR (52 ± 14 years), and 10 healthy controls (47 ± 16 years). Analysis included three-dimensional blood flow visualization and grading of helix flow in the ascending aorta (AAo) and arch. Peak systolic velocity was quantified in 9 analysis planes in the AAo, aortic arch, and descending aorta. Flow profile uniformity was evaluated in the aortic root and ascending aorta.

RESULTS

Peak systolic velocity (2.0 to 2.5m/second) in the aortic root and AAo in both VSARR and BIO-ARR were elevated compared with controls (1.1 to 1.3m/second, p < 0.005). Flow asymmetry in BIO-ARR was increased compared with VSARR, evidenced by more AAo outflow jets (9 of 16 BIO-ARR, 0 of 11 in VSARR). The BIO-ARR exhibited significantly (p < 0.001) increased helix flow in the AAo as a measure of increased flow derangement. Finally, peak systolic velocities were elevated at the aortic root for BIO-ARR (2.5 vs 2.0m/second, p < 0.05) but lower in the distal AAo when compared with VSARR.

CONCLUSIONS

The VSARR results in improved hemodynamic outcomes when compared with BIO-ARR, as indicated by reduced peak velocities in the aortic root and less helix flow in the AAo by 4D flow MRI. Longitudinal research assessing the clinical impact of these differences in hemodynamic outcomes is warranted.

Structure and function of the tricuspid and bicuspid regurgitant aortic valve: an echocardiographic study

OBJECTIVES

The emerging new treatment options for aortic valve disease call for more sophisticated diagnostics. We aimed to describe the echocardiographic pathophysiology and characteristics of the purely regurgitant aortic valve in detail.

METHODS

Twenty-nine men, with chronic aortic regurgitation without concomitant heart disease referred for aortic valve intervention, underwent 2D transoesophageal echocardiographic (TEE) examination prior to surgery according to a previously published matrix. Measurements of the aortic valve apparatus in long and short axis view were made in systole and diastole and analysed off-line. The aortic valves were grouped as tricuspid (TAV) or bicuspid (BAV), and classified by regurgitation mechanism.

RESULTS

Twenty-four examinations were eligible for analysis of which 13 presented TAV and 11 BAV. The regurgitation mechanism was classified as dilatation of the aorta in 6 cases, as prolapse in 11 cases and as poor cusp tissue quality or quantity in 7 cases. The ventriculo-aortic junction (VAJ) and valve opening were closely related (TAV r = 0.5, BAV r = 0.73) but no correlation was found between the VAJ and the maximal sinus diameter (maxSiD) or the sinotubular junction (STJ). However, the STJ and maxSiD were significantly related (TAV vs BAV: systole r = 0.9, r = 0.8; diastole r = 0.9, r = 0.7), forming an entity. The conjoined BAV cusps were shorter than the anterior cusps when closed (P = 0.002); the inter-commissural distances of the cusps in the BAV group were significantly different (P = 0.001 resp. 0.03) in both systole and diastole.

CONCLUSIONS

The VAJ was independent of other aortic dimensions and should thereby be considered as a separate entity with influence on valve opening. The detailed 2D TEE measurements of this study add further important information to our knowledge about the function and echocardiographic anatomy of the pathological aortic valve and root either as a stand-alone examination or as a benchmark and complement to 3D echocardiography. This may have an impact on decisions regarding repairability of the native aortic valve.

Personalised External Aortic Root Support (PEARS) Compared with Alternatives for People with Life-Threatening Genetically Determined Aneurysms of the Aortic Root

Personalised external aortic support was first proposed in 2000 by Tal Golesworthy, an engineer with familial Marfan syndrome and an aortic root aneurysm. After putting together a research and development team, and finding a surgeon to take on the challenge to join him in this innovative approach, he was central to the manufacture of the device, custom made for his own aorta. He was the patient for the ‘first in man’ operation in 2004. Ten years later he is well and 45 other people have had their own personalised device implanted. In this account, the stepwise record of proof of principle, comparative quantification of the surgical and perioperative requirements, 10 years of results, and development and research plans for the future are presented.

The evolution of surgical and medical treatment of aortic root aneurysm

Since first report of aortic root replacement in 1968, the surgical risk and long term outcome of patients with aortic root aneurysm have been continuously improving. In the last 30 years, the surgical approach is also evolving towards more valve conservation with prophylactical intervention at an earlier clinical stage. Translational research has also led to emerging surgical innovation and new drug therapy. Their efficacies are currently under vigorous clinical trials and evaluations.

A Bentall Is Not a Bentall Is Not a Bentall: The Evolution of Aortic Root Surgery

BACKGROUND

Aortic root pathology had been a known entity with a progressive and catastrophic course, long before the methods to surgically address them were first developed. Once reliable cardiopulmonary bypass was established, surgeons were able to pioneer new operative techniques, and in the half-century to follow, countless modifications and refinements have provided today's surgeons with the surgical approaches that are currently at their disposal.

HISTORY

Denton Cooley and Michael De Bakey reported the first successful surgical intervention for aneurysms involving the ascending aorta in 1956. Nearly a decade later, Hugh Bentall described his modification, and provided a name that would leave a lasting mark on aneurysmal surgery. In the decades to follow, numerous innovative surgeons improved on these original procedures to allow for a more reliable and consistent operation. Further, Tirone David and Sir Magdi Yacoub each described their methods to repair the aortic root while preserving the valve, thus providing their patients with freedom from a prosthetic or mechanical valve and improved quality of life.

CONCLUSIONS

The development of surgical techniques required to successfully care for patients with pathology of the aortic root has evolved considerably since Cooley and De Bakey's original report. Although it is common to hear aortic root replacement referred to as a "Bentall," the methods currently employed have gone through considerable evolution, such that the techniques of today should not be referred to as a Bentall.

Late outcome of noncoronary sinus replacement in patients with bicuspid aortic valves and aortopathy

BACKGROUND

Aortopathy associated with bicuspid aortic valve commonly involves the ascending aorta above the sinotubular ridge, but it may also affect sinus portions of the aorta. In some persons, the enlarged portion of the aortic root is limited to the noncoronary sinus. In such patients, we have spared the remaining portions of the aortic root by replacing the ascending aorta with a polyethylene terephthalate fiber (Dacron) graft and a tongue-shaped extension of the graft, thereby replacing the noncoronary sinus. In the present study, we evaluated late outcomes of this procedure, with specific attention to the fate of aortic tissue in the remaining sinuses.

METHODS

We reviewed the medical records of 1,756 patients with repair of ascending aortic aneurysms at Mayo Clinic from 1993 through 2012. Among the patients, 631 (35.9%) had bicuspid aortic valve, and in 79 (4.5%) of the patients, the noncoronary sinus was replaced along with the ascending aorta.

RESULTS

Associated aortic valve operations were performed in 70 patients; 15 had repair and 55 had aortic valve replacement. No early death occurred, but 3 patients died late after operation (5-year survival, 99%). There were 3 late reoperations, all because of native or prosthetic valve problems. Importantly, no instances occurred of aneurysm formation or aortic dissection related to the remaining aorta in the left and right aortic sinuses.

CONCLUSIONS

In patients with bicuspid aortic valve and aortic root enlargement related mainly to enlargement of the noncoronary sinus, limited replacement of the noncoronary sinus and ascending aorta is a safe and simple procedure that is durable in midterm follow-up.

Postpartum Stanford Type A Aortic Dissection: A Case Report and Review of the Literature

Acute aortic dissection is a life-threatening disease. Approximately half of the aortic dissection observed in women under 45 years old has been reported to be related to pregnancy. Herein, we present a case of type A aortic dissection diagnosed in postpartum period. A 37-year-old woman admitted to the emergency department with the complaint of sudden onset of dyspnea. Arterial blood pressure was measured as 170/100 mmHg in left arm and 90/60 mmHg in right arm. With a prediagnosis of aortic dissection, thoracic and abdominal computed tomograpy was performed and type A aortic dissection extending form carotid artery to renal arterial level was detected. Operation of aortic dissection together with coronary arterial repairment and aortic valve replacement were successfully performed. Aortic dissection is not uncommon in pregnancy and furthermore it is potentially life-threatening for both mother and fetus. A high level of suspicion is required for prompt diagnosis and treatment in the peripartum period.

Cardiovascular magnetic resonance in Marfan syndrome

This review provides an overview of Marfan syndrome with an emphasis on cardiovascular complications and cardiovascular imaging. Both pre- and post-operative imaging is addressed with an explanation of surgical management. All relevant imaging modalities are discussed with a particular focus on cardiovascular MR.

Multiple aneurysms in a patient with aneurysms-osteoarthritis syndrome

The aneurysms-osteoarthritis syndrome (AOS) was recently described and encompasses multiple aneurysms and tortuosity of the great arteries. Most patients have early-onset osteoarthritis. We report the diagnosis, treatment, and follow-up of a patient presenting with bilateral aneurysms of the common iliac arteries and an ascending aortic aneurysm. After proper surgical treatment, genetic studies revealed a causal mutation in the SMAD3 gene.

Clinical experience with the Bentall procedure: 28 years

PURPOSE

We retrospectively analyzed 28 years of experience with the Bentall procedure in patients with aortic valve, aortic root, and ascending aortic disease.

MATERIALS AND METHODS

Between March 1982 and December 2010, a total of 218 patients underwent the Bentall procedure using a composite valved conduit. The "inclusion technique" was used in 30 patients (13.8%), the "open-button technique" in 181 patients (83.0%), and the Cabrol technique in 7 patients (3.2%).

RESULTS

The early mortality rate was 5.5% (12/218). The mean follow-up duration was 108.0±81.0 months (range: 1-329 months). Seven patients required re-operation, and 1 patient required stent graft insertion at the descending thoracic aorta for progression of aortic arch or descending thoracic aortic dissection or aneurysm after the first operation, and 5 of them had Marfan syndrome. Kaplan-Meier estimated survival rates at 1, 5, 10, 20, and 25 years were 90.4%, 82.7%, 77.6%, 65.3%, and 60.3%, respectively. Freedom from reoperation rates at 1, 5, 10, 20, and 25 years were 99.0%, 98.3%, 95.5%, 90.8%, and 90.8%, respectively.

CONCLUSION

In our experience, the Bentall procedure provided optimal survival with improved functional status. The disease of the aorta may progress, especially in patients with Marfan syndrome. Therefore, careful follow-up with regular computed tomography angiograms should be performed in these patients.

Long-term results after aortic valve-sparing operation (David I)

OBJECTIVE

Aortic valve-sparing David procedure has gained broad acceptance. However, few long-term results have been published. We present our results.

METHODS

More than 450 David procedures have been performed in our institution so far. Of these, 126 patients were operated between July 1993 and December 2000. Median age was 57 (8-83) years and 46 (36.5%) were female. As many as 26 (20.6%) had Marfan syndrome, 21 (16.7%) had acute aortic dissection type A (AADA) and 67 (53.2%) had additional procedures.

RESULTS

There were six (4.8%) deaths in 30 post-operative period (POD), four of whom had AADA. In the follow-up, there were 32 (25.4%) late deaths, 11 (34.4%) of these were caused by cardiac or underlying disease or op-related. As many as 15 (11.9%) patients were re-operated; six (40%) were Marfan patients and two (13.3%) had early endocarditis. Follow-up echocardiography of 76 (60.3%) event-free patients showed valve insufficiency (AI)≤AI I° in 68 (89.5%) and grade II in 7 (9.2%) patients. Leaflet degeneration due to proposed leaflet contact with the straight Dacron graft was not observed. A total of 36 (47.4%) patients were in New York Heart Association (NYHA) class I, 33 (43.4%) in NYHA II, and five (6.6%) were in class III. During the entire follow-up of 790 patient-years, there was no stroke or major bleeding. Survival at 1, 5 and 10 years was 93%, 85% and 70%, respectively. Freedom from valve replacement at 1, 5 and 10 years was 96%, 91% and 87%, respectively.

CONCLUSIONS

Regardless of the underlying pathology, valve-sparing David I procedure has acceptable long-term results. Valve-related complications such as stroke or major bleeding is exceedingly low.

A method for early evaluation of a recently introduced technology by deriving a comparative group from existing clinical data: a case study in external support of the Marfan aortic root

OBJECTIVE

During the early phase of evaluation of a new intervention, data exist for present practice. The authors propose a method of constructing a fair comparator group using these data. In this case study, the authors use the example of external aortic root support, a novel alternative to aortic root replacement.

DESIGN

A matched comparison group, of similar age, aortic size and aortic valve function to those having the novel intervention, was constructed, by minimization, from among patients having conventional aortic root replacement in other hospitals during the same time frame.

SETTING

Three cardiac surgical units in England.

PATIENTS

The first 20 patients, aged 16-58 years with aortic root diameters of 40-54 mm, having external support surgery were compared with 20 patients, aged 18-63 years and aortic root diameters of 38-58 mm, who had conventional aortic root replacement, between May 2004 and December 2009.

INTERVENTIONS

A pliant external mesh sleeve, customised by computer-aided design, encloses the whole of the ascending aorta. The comparator group had conventional aortic root replacement, 16 valve-sparing and four with composite valved grafts.

MAIN OUTCOME MEASURES

Duration of cardiopulmonary bypass (CPB), myocardial ischaemic time, blood loss and transfusion of blood, platelets and clotting factors.

RESULTS

Comparing total root replacement and customised aortic root support surgery: CPB (median (range)) was 134 (52-316) versus 0 (0-20) min; myocardial ischaemia 114 (41-250) versus 0 (0-0) min; 4 h blood loss was 218 (85-735) versus 50 (25-400) ml; and 9/18 had blood transfusion, 9/18 platelets and 12/18 fresh frozen plasma after root replacement versus 1/20, 0/20 and 0/20, respectively, for the novel surgery.

CONCLUSIONS

Avoidance or large reductions in CPB, myocardial ischaemia and blood product usage were achieved with the novel surgery. These data are of use in decision analysis and health economic evaluation and are available early in evaluation before randomised trial data are available.

FINITE ELEMENT SIMULATIONS OF THE PHYSIOLOGICAL AORTIC ROOT AND VALVE SPARING CORRECTIONS

A 3-D model of the aortic root was developed consisting of aortic valve, sinus of Valsalva and aortic duct. Through finite element modeling, the mechanical behavior of the valve was investigated simulating four different configurations: physiological (baseline), aneurysmatic and corrected with two different sparing techniques, named after David and Yacoub, respectively. These surgical procedures imply the replacement of the sinus of Valsalva with a synthetic graft, inside which the cusps are resuspended. The final goal of this study consisted in the assessment of the mechanical effects of sinuses aneurysm on the whole root, as well as the effectiveness of the two aforementioned techniques in restoring valve functionality and normal stress values on the root substructures. Based on the assumption of three-leaflet symmetry, only one third of the aortic root was modeled. Two cardiac cycles were simulated and the mechanical behavior of the aortic root was evaluated in terms of stress pattern, contact pressure and contact areas observed during leaflets coaptation and when contact between the leaflet and the graft occurs. Both the sparing techniques are able to restore coaptation of the aortic valve, but for the David procedure, contact between the leaflet and the graft wall was detected.

Cardiovascular surgery in Marfan syndrome: implications of new molecular concepts in thoracic aortic disease

Acute dissection and rupture of aortic aneurysms comprise for 1–2% of all deaths in industrialized countries. Dilation of the aorta is caused by a multitude of mechanisms including inherited connective tissue disorders such as Marfan syndrome (MFS). MFS is one of the most common inherited connective tissue disorders affecting 1 in 5000 individuals. Although the phenotype of MFS can be quite variable, aneurysmal dilation of the aortic root and consecutive acute aortic dissection is the leading cause of death in this patient population. Over the past years it has been shown that a comprehensive understanding of this disorder provides greater understanding of vascular wall biology and identifies pathways relevant to aortic aneurysms and dissection in general. The current review discusses the surgical management of patients with MFS with a special emphasis on indications for surgery in this complex group of patients.

Aortic valve-sparing operations: state of the art

PURPOSE OF REVIEW

Aortic valve-sparing (AVS) operations include an armamentarium of procedures, which preserve the aortic cusps in aortic root dilation with aortic insufficiency. The purpose of this review article is to specifically outline the surgical indications, to describe the various techniques, and to present results from the most current series in AVS operations.

RECENT FINDINGS

In the worldwide literature, there is promising data on AVS operations. Patients undergoing AVS operations not only have better long-term survival but also appear to have a reduced risk of aortic insufficiency and thromboembolic complications.

SUMMARY

AVS operations are an excellent option for patients with an aortic root aneurysm and normal/minimally diseased aortic cusps.

Medial necrosis in aortic root aneurysm after repair of tetralogy of Fallot

Aneurysmal dilatation of the aortic root occurs in some patients with tetralogy of Fallot (TOF) late after repair. It can lead to aortic valve insufficiency and rarely to aortic rupture or dissection. Aortic valve or aortic surgery is rarely performed in this group of patients. We present a case of aneurysmal dilatation of the ascending aorta treated with aortic valve sparing root replacement 43 years after the TOF repair. Histological examination of the aortic wall revealed medial necrosis. The implications of those finding and the timing of surgery are discussed.

Valve-sparing aortic root reconstruction

The aortic valve-sparing root reconstruction procedure remains an ideal concept, but it has not yet become an ideal operation. There is still great variation and evolution in techniques, which mirrors the increasing understanding of the aortic root's functional anatomy and the disease processes that affect it. These operations remain complex, and the surgeons who perform them well are often times best armed with an experienced eye for what looks right more than a mathematical model that can predetermine who will do well, with what repair type and with what percentage chance of long-term success. Because of this, it will likely still be a while before these operations are more routinely used by a broader group of surgeons, as compared with the very reproducible Bentall and De Bono repair.

Artificial neural networks versus multiple logistic regression to predict 30-day mortality after operations for type a ascending aortic dissection

Background:

There are few comparative reports on the overall accuracy of neural networks (NN), assessed only versus multiple logistic regression (LR), to predict events in cardiovascular surgery studies and none has been performed among acute aortic dissection (AAD) Type A patients.

Objectives:

We aimed at investigating the predictive potential of 30-day mortality by a large series of risk factors in AAD Type A patients comparing the overall performance of NN versus LR.

Methods:

We investigated 121 plus 87 AAD Type A patients consecutively operated during 7 years in two Centres. Forced and stepwise NN and LR solutions were obtained and compared, using receiver operating characteristic area under the curve (AUC) and their 95% confidence intervals (CI) and Gini’s coefficients. Both NN and LR models were re-applied to data from the second Centre to adhere to a methodological imperative with NN.

Results:

Forced LR solutions provided AUC 87.9±4.1% (CI: 80.7 to 93.2%) and 85.7±5.2% (CI: 78.5 to 91.1%) in the first and second Centre, respectively. Stepwise NN solution of the first Centre had AUC 90.5±3.7% (CI: 83.8 to 95.1%). The Gini’s coefficients for LR and NN stepwise solutions of the first Centre were 0.712 and 0.816, respectively. When the LR and NN stepwise solutions were re-applied to the second Centre data, Gini’s coefficients were, respectively, 0.761 and 0.850. Few predictors were selected in common by LR and NN models: the presence of pre-operative shock, intubation and neurological symptoms, immediate post-operative presence of dialysis in continuous and the quantity of post-operative bleeding in the first 24 h. The length of extracorporeal circulation, post-operative chronic renal failure and the year of surgery were specifically detected by NN.

Conclusions:

Different from the International Registry of AAD, operative and immediate post-operative factors were seen as potential predictors of short-term mortality. We report a higher overall predictive accuracy with NN than with LR. However, the list of potential risk factors to predict 30-day mortality after AAD Type A by NN model is not enlarged significantly.