Aortic valve repair with patch in non-rheumatic disease: indication, techniques and durability†

The Prevalence of Coronary Artery Disease in Bicuspid Aortic Valve Patients: An Overview of the Literature

The prevalence of coronary artery disease (CAD) in bicuspid aortic valve (BAV) patients is a debatable topic. Several studies have indicated that BAV patients have a lower prevalence of CAD compared with patients with a tricuspid aortic valve (TAV), but the effects of age and gender have not always been considered. This systematic review provides an overview of articles which report on CAD in BAV and TAV patients. Searches were executed in April 2021 and January 2022 according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-analyses) guidelines in three online databases: Medline, Embase, and Scopus. Screening and data extraction was done by two investigators separately. Primary and secondary outcomes were compared between BAV and TAV patients; a fixed effects model was used for correcting on confounders. Literature search yielded 1,529 articles with 44 being eligible for inclusion. BAV patients were younger (56.4 ± 8.3 years) than TAV patients (64 ± 10.3 years, p < 0.001). All CAD risk factors and CAD were more prevalent in TAV patients. No significant difference remained after correcting for age and gender as confounders. BAV patients have a lower prevalence of CAD and CAD risk factors compared with TAV patients. However, when the age differences between both groups are considered in the analyses, a similar prevalence of both CAD and CAD risk factors is found.

Current controversies in aortic valve-preserving surgery

The clinical outcome of severe aortic regurgitation (AR) remains suboptimal, but surgery has been shown to have survival benefit over medical therapy. Postoperative survival is inferior in patients with reduced left ventricular function, and therefore early surgical intervention is recommended. Aortic valvuloplasty (AVP) is an attractive option to avoid the major drawbacks of prosthetic valves but has not been widely adopted. The etiology of AR is classified functionally into three groups: normal leaflet motion (type I), cusp prolapse (type II), and restriction (type III). Type I with dilatation of the sinus of Valsalva (type Ib) can be repaired by aortic valve reimplantation or aortic root remodeling with similar valve stability. Type I with dilatation of the aortic annulus (type Ic) can be managed by annuloplasty. Type II can be corrected by plication or resuspension techniques. Pericardial patch is necessary in AVP for type Id (perforation/fenestration) and type III but is associated with risk of recurrence. Bicuspid aortic valve is classified according to commissure angle: symmetrical, asymmetrical, and very asymmetrical. Tricuspidization is recommended for repair of very asymmetrical valves to avoid postoperative stenosis. Recent progress has achieved similar reoperation rates between bicuspid and tricuspid aortic valve repair. For Marfan syndrome, valve-sparing root replacement is advantageous compared to Bentall operation regarding late survival, thromboembolic and hemorrhagic events, and endocarditis. Similar findings have been reported in acute aortic dissection. Both remodeling and reimplantation procedures provide similar favorable outcomes in these settings. Recent advances in AVP are summarized by quantitative assessment of cusp configuration (effective height and geometric height), graft size decision, use of template to cut the graft, and videoscopic assessment of post-repair cusp configuration. Due to these advances, AVP shows superior results to replacement surgery. Further concrete evidence with larger case volumes and longer observation periods are necessary to popularize AVP.

Longer-term outcomes after bicuspid aortic valve repair in 142 patients

BACKGROUND

The aim of this study was to evaluate the longer-term results of bicuspid aortic valve (BAV) repair with or without aortic root replacement.

METHODS

From 1999 to 2017, 142 patients with or without aortic root dilatation who underwent repair of a regurgitant BAV were included in the study. Ninety-four patients underwent isolated BAV repair (Group 1; median age 43 years) and 48 patients underwent valve-sparing aortic root replacement plus BAV repair (aortic valve reimplantation-Group 2; median age 48 years). Median clinical follow-up time was 5.9 years (range 0.5-15) in Group 1 and 3 years (range 0.5-16) in Group 2, respectively.

RESULTS

In-hospital mortality was 1% in Group 1, and 2% in Group 2 (p = .6). The 5- and 10-year survival was 93 ± 2.9% and 81 ± 5.8% in Group 1 and 96 ± 3.1% and 96 ± 3.1% in Group 2, respectively (p = .31). Eleven patients of Group 1 (1.7%/patient-year) and five patients of Group 2 (2.2%/patient-year) underwent reoperation of the aortic valve (p = .5). The 5- and 10-year freedom from reoperation were 93.0 ± 2.1% and 77.1 ± 7.1% in Group 1 and 93.0 ± 5.0% and 76.7 ± 9.6% in Group 2 (p = .83), respectively. At the latest follow-up, only two patients of Group 1 and 1 patient of Group 2 had AV regurgitation = 2° (p = .7). The cumulative linearized incidence of all valve-related complications (bleeding, stroke, endocarditis, and reoperation) was 2.9%/patient-year in Group 1% and 4%/patient-year in Group 2, respectively (p = .6).

CONCLUSIONS

Isolated BAV repair and combined aortic valve reimplantation plus BAV repair provide good clinical longer-term outcomes with relatively low reoperation rate and durable valve function.

Aortic valve repair in endocarditis: scope and results

Purpose

Infective endocarditis (IE) remains a prevalent and life-threatening disease. The choice to repair or replace the infected valve still remains a matter of debate, especially in aortic valve (AV) infections. We retrospectively analyze our two decades of experience in aortic valve repair (AVr) in IE. Long-term outcomes are described with particular attention to the impact of valve configuration and the use of patch techniques.

Methods

From September 1998 to June 2017, 42 patients underwent AVr in a single center for IE. Techniques include leaflet patch repair and resuspension and aortic annulus stabilization.

Results

Hospital mortality was 2.4% (n = 1). The median follow-up was 90.6 months. Survival was 89 ± 9.4% and 76.6 ± 16% at 5 and 10 years, respectively, with no significant differences between tricuspid aortic valve (TAV) and bicuspid aortic valve (BAV). Freedom from reoperation was 100% and 92.9 ± 7.1% in TAV and 81.8 ± 18.2% and 46.8 ± 28.8% in BAV at 5 and 10 years, respectively (TAV vs BAV, p = 0.02). BAV, degree of preoperative aortic insufficiency, and AVr including patch were factors predicting a higher risk of reoperation during the follow-up.

Conclusion

In our experience, AVr is a safe, feasible, and efficient choice in selected patients with healed or active IE. Durability of the repair is excellent in patients with limited lesions and in patients with TAV even with patch repair. Reoperations occurred principally in patients with BAV and severe preoperative AI, in whom patch repair was performed. In those patients, we actually recommend to replace the valve in case of active endocarditis.

State-of-the art bicuspid aortic valve repair in 2020

Patients with a bicuspid aortic valve (BAV) frequently require surgical intervention for aortic regurgitation (AR) and/or aneurysm. Valve-preserving surgery and repair of regurgitant BAVs have evolved into an increasingly used alternative to replacement. Anatomic predictors of possible repair failures have been identified and solutions developed. Using current techniques most non-calcified BAVs can be preserved or repaired. Excellent repair durability and freedom from valve-related complications can be achieved if all pathologic components of aortic valve and root including annular dilatation are corrected. Anatomic variations must be addressed using tailored approaches.

Clinical and Echocardiographic Outcomes After Aortic Valve Repair Surgery

OBJECTIVE

To assess early and late clinical outcomes in patients who underwent aortic valve repair surgery for aortic valve insufficiency, and to investigate predictors for recurrence.

METHODS

Of 151 consecutive patients who underwent aortic valve repair surgery for varying degrees of aortic insufficiency (AI) in our department between 2004 and 2018, 60 (40%) underwent aortic root replacement, 71 (47%) aortic cusp plication, 31 (20%) subcommissural annuloplasty, 29 (19%) circular annuloplasty, and 28 (18%) autologous pericardial patch augmentation.

RESULTS

One patient died in the hospital (0.7%). Mean clinical and echocardiographic follow-up was 62±43 months (range 1 to 159) and 50 ± 40 months (range 1 to 158), respectively. The overall survival rate was 99.3% at 1 year and 98% at 5 years of follow-up. Seventeen patients (11.3%) had recurrent severe AI, and all of them underwent reoperation with a mean duration to reoperation of 35 ± 39 months. Risk factors for the development of recurrent significant AI (≥3) or reoperation, by univariable analysis, were unicuspid or bicuspid aortic valve (AV) (P = 0.018), the use of subcommissural annuloplasty (P = 0.010), the need for cusp repair (P = 0.001), and the use of pericardial patch augmentation (P < 0.001). By multivariable analysis only the use of pericardial patch augmentation emerged as a significant independent predictor for the development of recurrent significant AI (≥3) or reoperation (P = 0.020).

CONCLUSION

AV repair can be performed with low morbidity and mortality, with good early and late clinical outcomes. However, in our experience there was a significant rate of recurrent AI especially in patients who underwent cusp augmentation using glutaraldehyde-treated autologous pericardial patch.

Use of Pericardium for Cardiac Reconstruction Procedures in Acquired Heart Diseases-A Comprehensive Review

BACKGROUND

Reconstruction of cardiac structures has been the goal of many surgeons even before the advent of open-heart procedures with cardiopulmonary bypass. Unsatisfactory results with synthetic materials has switched the attention to biological tissues, among which pericardium, either autologous or of animal origin, has been widely used as patch material.

METHODS

We have reviewed the literature to assess the effective role of pericardial tissue in the correction of various acquired cardiac lesions. Particularly, special attention was given not only to established techniques but also to detect any peculiar and unusual application of pericardium.

RESULTS

Autologous pericardium is frequently used as patch material particularly when limited valvular lesions must be corrected, while xenograft pericardium appears particularly useful in patients with endocarditis and extensive destruction of the intracardiac structures by infection and abscesses. Pericardium is an extremely versatile material owing to its pliability and strength; however, it tends to calcify in the long term when in contact with blood, although stability of the repair is maintained in most cases.

CONCLUSIONS

Pericardium plays an important role in various cardiac and aortic pathologies. Tissues resistant to fibrosis and calcification to be used as patch material are the ideal solution for more successful cardiac reconstruction procedures and will hopefully be provided by the ongoing research.

Successful Truncal Valve Replacement After Truncal Valve Repairs

The surgical management of severe truncal valvular dysfunction is still challenging in neonates with persistent truncus arteriosus. This report describes a 14-day-old neonate with severe truncal valve insufficiency successfully undergoing truncal valve repairs, and followed by valve replacement at the age of 4 years. The truncal valve was quadricuspid with two large and two small leaflets, and all leaflets had severe dysplastic and myxomatous changes. We performed leaflet extension and bicuspidization valvuloplasty for this valve. This patient obtained somatic growth for 4 years without heart failure symptoms, and safely underwent prosthetic valve replacement. This technique would be effective for truncal valve dysfunction in neonates as the life-saving and the bridging procedure to valve replacement.

Predictors of Aortic Valve Repair Failure

Aortic valve repair is the preferred approach for the treatment of severe aortic insufficiency (AI), as it allows patients to keep their native aortic valve, thus substantially reducing the risk of prosthesis-related complications. Several studies have documented excellent long-term outcomes of aortic valve repair. The major complication of this operation is AI recurrence, with ensuingneed for reoperation. The surgical experience accumulated over the last two decades has allowed for better understanding of the mechanisms of recurrent AI after aortic valve repair. Herein, we review the current state of knowledge on predictors of aortic valve repair failure. These include unaddressed annular dilation, residual cusp prolapse or retraction, commissural orientation, and use of patch material. This enhanced understanding has led to the development of increasingly refined techniques and improved patient outcomes. Continued follow-up and detailed data collection at the time of surgery, together with three-dimensional echo imaging, will allow further improvements in aortic valve repair.

The great debate series: surgical treatment of aortic valve abnormalities in children

This article is the latest in an EJCTS series entitled 'The Great Debates'. We have chosen the topic of aortic valve (AoV) surgery in children, with a focus on infants and neonates. The topic was selected due to the significant challenges that AoV problems in the young may present to the surgical team. There are many areas of active controversy, despite the vast accumulated world experience. We have tried to incorporate many of these issues in the questions posed, not claiming to be all-inclusive. The individuals invited to this debate are experts in paediatric valve surgery, with broad and successful clinical experiences on multiple continents. We hope that the facts and opinions presented in this debate will generate interest and discussion and perhaps prove useful in decision-making for future complex valve cases.

Aortic Valve Repair of a Stenotic Unicuspid Aortic Valve in Young Patients

BACKGROUND

The unicuspid aortic valve (UAV) is a well-described pediatric congenital abnormality, with incidence of 0.02% in the general population. Bicuspidization has been described as a potential surgical option to repair this defect.

METHODS

Seventeen symptomatic young patients with a unicuspid valve combined with either valve insufficiency or valve stenosis underwent aortic valve (AV) bicuspidization procedure by using an equine pericardium. In addition to bicuspidization, 8 patients underwent aortic ring implantation and 5 patients underwent supracoronary replacement of the aorta.

RESULTS

Our results show safety of the bicuspidization procedure. No deaths occurred during our average follow-up period of 26 months. Freedom from reoperation for any valve-related reason was 100% during this follow-up period. We observed a statistically significant increase in the AV area from 0.8 ± 0.1 cm² to 2.8 ± 0.7 cm² (p < 0.01), a statistically significant decrease in the mean systolic pressure gradient from 36 ± 13.3 mm Hg to 9 ± 4 mm Hg (p < 0.001), a statistically significant decrease in aortic insufficiency grade from 2.1 ± 1.0 to 0.6 ± 0.7 (p < 0.01) before and after bicuspidization, respectively, and a statistically significant decrease in the left ventricular end-diastolic diameter from 49.88 ± 5.11 mm to 40.46 ± 7.20 mm (p < 0.0005) and a statistically significant increase of the left ventricular ejection fraction from 56% ± 8.20% to 64% ± 7.83% at the time of follow-up.

CONCLUSIONS

From our study, bicuspidization is an attractive surgical option to repair UAV, particularly in young patients who do not want to be subjected to long-term anticoagulation therapy or who refuse a more traditional surgical approach, such as Ross procedure, for reasons described previously.

Calcific Degeneration of CorMatrix 4 Years After Bicuspidization of Unicuspid Aortic Valve

We report the long-term outcomes of a 12-year-old boy who underwent bicuspidization of a severely stenotic unicuspid aortic valve with CorMatrix small intestinal submucosal extracellular matrix (CorMatrix Cardiovascular, Roswell, GA). CorMatrix supported favorable immediate surgical and echocardiographic outcomes and maintained stable growing functional dynamics for 2 years. At 52.5 months in situ, however, the valve failed with severe calcification, fibrosis, and retraction necessitating a redo operation. Reconstructive operations with CorMatrix are feasible, but this result questions its capacity for constructive remodeling in left-sided valve repair.

Iatrogenic Aortic Valve Perforation after Ventricular Septal Defect Repair

Iatrogenic aortic valve (AV) perforation during non-aortic cardiac operations is a rare complication. The suture-related inadvertent injury to an AV leaflet can produce leaflet perforation with aortic regurgitation after ventricular septal defect repair (VSDR). We report three consecutive patients who had iatrogenic aortic leaflet perforation during VSDR in other hospitals and referred to our hospital for reoperation. In all three cases, the perforated AV leaflets were preserved and repaired by autologous pericardial patch or direct local closure.

Reconstructive surgery of the aortic valve

Reconstructive surgery of the aortic valve is a safe alternative to aortic valve replacement in many patients with aortic regurgitation, with satisfactory durability and an overall and cardiovascular survival advantage. It is also associated with higher rates of freedom from valve-related and anticoagulation-related events.

CorMatrix valved conduit in a porcine model: long-term remodelling and biomechanical characterization

OBJECTIVES

Porcine small intestinal submucosa extracellular matrix (CorMatrix; CorMatrix Cardiovascular, Rosewell, GA) is a relatively novel tissue substitute used in cardiovascular applications. We investigated the biological reaction and remodelling of CorMatrix as a tri-leaflet valved conduit in a pig model. We hypothesized that CorMatrix maintains a durable architecture as a valved conduit and remodels to resemble surrounding tissues.

METHODS

We fashioned the valved conduit using a 7 × 10 cm 4-ply CorMatrix sheet and placed it in the thoracic aorta of seven landrace pigs for 3, 4, 5 and 6 months. Biodegradation, replacement by native tissue, strength and durability were examined by histology, immunohistochemistry and mechanical testing.

RESULTS

Four pigs, one per time frame, completed the study. The conduit lost its original architecture as a tri-leaflet valve due to cusp immobility, subsequent attachment to the wall segment and consequent maintenance of a thick arterial wall-like structure. Scaffold resorption was incomplete, with disorganized inconsistent spatial and temporal degradation even at 6 months. Fibrosis, scarring and calcification started at 4 months and chronic inflammation persisted. The partially remodelled scaffold did not resemble the aortic wall, suggesting impaired remodelling. Mechanical testing showed progressive weakening of the tissues over time, which were liable to breakage.

CONCLUSIONS

CorMatrix is biodegradable; however, it failed to remodel in a structured and anatomical fashion in an arterial environment. Progressive mechanical and remodelling failure in this scenario might be explained by the complexity of the conduit design and the host's chronic inflammatory response, leading to early fibrosis and calcification.

Impact of Valve Morphology on the Prevalence of Coronary Artery Disease: A Systematic Review and Meta-Analysis

Background

Literature studies suggested a lower prevalence of coronary artery disease (CAD) in bicuspid aortic valve (BAV) than in tricuspid aortic valve (TAV) patients. However, this finding has been challenged. We performed a meta‐analysis to assess whether aortic valve morphology has a different association with CAD, concomitant coronary artery bypass grafting (CABG), and postoperative mortality.

Methods and Results

Detailed search was conducted according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta‐Analyses) guideline to identify all patients with BAV or TAV and presence of CAD, concomitant myocardial surgical revascularization, and the postoperative mortality. Thirty‐one studies on 3017 BAV and 4586 TAV patients undergoing aortic valve surgery were included. BAV patients showed a lower prevalence of CAD (odds ratio [OR]: 0.33; 95% CI: 0.17, 0.65), concomitant CABG (OR, 0.45; 95% CI: 0.35, 0.59), and postoperative mortality (OR, 0.62; 95% CI: 0.40, 0.97) than TAV. However, BAV subjects were significantly younger than TAV (mean difference: −7.29; 95% CI: −11.17, −3.41) were more frequently males (OR, 1.61; 95% CI: 1.33, 1.94) and exhibited a lower prevalence of hypertension (OR, 0.58; 95% CI: 0.39, 0.87) and diabetes (OR, 0.71; 95% CI: 0.54, 0.93). Interestingly, a metaregression analysis showed that younger age and lower prevalence of diabetes were associated with lower prevalence of CAD (Z value: −3.03; P=0.002 and Z value: −3.10; P=0.002, respectively) and CABG (Z value: −2.69; P=0.007 and Z value: −3.36; P=0.001, respectively) documented in BAV patients.

Conclusions

Analysis of raw data suggested an association of aortic valve morphology with prevalence of CAD, concomitant CABG, and postoperative mortality. Interestingly, the differences in age and diabetes have a profound impact on prevalence of CAD between BAV and TAV. In conclusion, our meta‐analysis suggests that the presence of CAD is independent of aortic valve morphology.

Year in review: complex valve reconstruction

PURPOSE OF REVIEW

In recent years, great emphasis has been placed on reconstructive techniques for the surgical management of heart valve disease. In this review, we discuss recent data and current practice as it pertains to the subject of reconstructive valve surgery.

RECENT FINDINGS

New techniques and an improved understanding of the mechanisms of aortic insufficiency have led to marked improvement in the early and late outcomes of aortic valve repair. While mitral valve repair is the established approach for the management of degenerative mitral valve disease, surgical technique continues to be refined, with valve reconstruction principles applied to increasingly challenging anatomy. Moreover, the introduction of novel biomaterials has allowed extension of the indication for valve reconstruction to circumstances of extensive tissue defect, including infective endocarditis.

SUMMARY

Valve reconstruction is increasingly being recognized as an alternative to valve replacement. It alleviates the risks of prosthesis-related complications and is especially appealing in young and middle-aged adults. While early and midterm outcomes appear promising, further studies are warranted to assess the clinical benefit and long-term durability of complex valve reconstruction procedures.

Aortic cusp sizers to establish the functional classification of aortic insufficiency: algorithm and midterm outcome of operative repair

OBJECTIVES

Wider adoption of aortic valve repair procedures is held up by the difficulty in recognizing the exact alterations that are responsible for aortic valve insufficiency. New aortic cusp sizers were developed to assist in aortic valve assessment in the operating theatre. Our objectives were to examine the efficacy of the aortic cusp sizers in establishing the functional classification of aortic valve insufficiency, and to report the midterm outcome in a group of patients who had undergone aortic valve repair guided by this device.

METHODS

A prospective clinical study was performed involving 33 consecutive patients (18 males, age range: 8-74 years) with severe aortic valve insufficiency (mean severity: 3.4 ± 0.5). The aortic cusp sizers were used as a template to identify existing cusp and root alterations. Consequently, the functional classification of aortic insufficiency was determined, and the appropriate techniques of aortic valve repair were implemented.

RESULTS

Aortic valve repair was successful in all patients. Procedures performed were 37 functional aortic annulus corrections, 9 cusp free-edge plications, 2 cusp repairs with autologous pericardium, 9 replacements of the ascending aorta and 2 reimplantation procedures. At a mean follow-up time of 18.3 ± 13.7 months, 1 patient underwent aortic valve replacement for recurrent aortic valve regurgitation, while aortic valve function remained stable in 32 patients, with aortic insufficiency <1+ in 27 (84.4%) patients and 1-1.5 in 5 (15.6%) patients, and no significant gradients across the aortic valves.

CONCLUSIONS

The aortic cusp sizers are valuable in establishing the functional classification of aortic insufficiency, and can guide implementation of aortic valve repair techniques successfully. This approach is analogous to that accredited for the success and wide adoption of mitral valve repair techniques, and is likely to assist in increasing the percentage of aortic valves that are repaired when compared with current practice.