Toward predictable repair of regurgitant aortic valves: a systematic morphology-directed approach to bicommissural repair

2023 Korean Society of Echocardiography position paper for diagnosis and management of valvular heart disease, part I: aortic valve disease

This manuscript represents the official position of the Korean Society of Echocardiography on valvular heart diseases. This position paper focuses on the clinical management of valvular heart diseases with reference to the guidelines recently published by the American College of Cardiology/American Heart Association and the European Society of Cardiology. The committee tried to reflect the recently published results on the topic of valvular heart diseases and Korean data by a systematic literature search based on validity and relevance. In part I of this article, we will review and discuss the current position of aortic valve disease in Korea.

Well-functioning bicuspid aortic valves should be preserved during aortic replacement for the ascending aortopathy phenotype

OBJECTIVES

Consensus has not been reached on whether or not to replace or preserve a well-functioning bicuspid aortic valve (BAV) in patients undergoing aortic replacement for the ascending phenotype of BAV aortopathy. We characterize morphology, evaluate progression of aortic regurgitation or aortic stenosis, and investigate the need for aortic valve replacement in patients whose well-functioning BAV was preserved during ascending aortic replacement ≥10 years prior.

METHODS

From January 1991 to August 2011, 191 patients with a well-functioning BAV underwent supracoronary aortic replacement (113 valves were minimally repaired). Aortic morphology was evaluated, aortic regurgitation grade and transvalvular aortic gradient modeled parametrically, and survival assessed by the Kaplan-Meier method. Median follow-up was 10 years.

RESULTS

Mean aortic diameter was 2.9 ± 0.53 cm at the annulus and 4.2 ± 0.55 cm at the sinuses. Mean maximum ascending diameter was 5.1 ± 0.49 cm. All patients exhibited a cusp-fusion BAV phenotype. Fifteen-year progression to severe aortic regurgitation was 3.2%. Mean aortic valve gradient began to rise 5 years postoperatively to 27 mm Hg by 14 years. Freedom from aortic valve replacement at 1, 5, 10, and 15 years was 100%, 95%, 83%, and 63%, respectively. Minimal valve repair was not associated with late aortic valve replacement. Fifteen-year survival was 74%.

CONCLUSIONS

Preserving a well-functioning BAV should be considered in carefully selected patients undergoing aortic replacement for the ascending phenotype of BAV aortopathy. The valves remain durable in the long term, with slow progression of regurgitation or stenosis, and low probability of aortic valve replacement through 10 years.

Aortic valve cusp repair does not affect durability of modified aortic valve reimplantation for tricuspid aortic valves

Objective

During aortic valve reimplantation, cusp repair may be needed to produce a competent valve. We investigated whether the need for aortic valve cusp repair affects aortic valve reimplantation durability.

Methods

Patients with tricuspid aortic valves who underwent aortic valve reimplantation from January 2002 to January 2020 at a single center were retrospectively analyzed. Propensity matching was used to compare outcomes between patients who did and did not require aortic valve cusp repair.

Results

Cusp repair was performed in 181 of 756 patients (24%). Patients who required cusp repair were more often male, were older, had more aortic valve regurgitation, and less often had connective tissue disease. Patients who underwent cusp repair had longer aortic clamp time (124 ± 43 minutes vs 107 ± 36 minutes, P = .001). In-hospital outcomes were similar between groups and with no operative deaths. A total of 98.3% of patients with cusp repair and 99.3% of patients without cusp repair had mild or less aortic regurgitation at discharge. The median follow-up was 3.9 and 3.2 years for the cusp repair and no cusp repair groups, respectively. At 10 years, estimated prevalence of moderate or more aortic regurgitation was 12% for patients with cusp repair and 7.0% for patients without cusp repair (P = .30). Mean aortic valve gradients were 6.2 mm Hg and 8.0 mm Hg, respectively (P = .01). Ten-year freedom from reoperation was 99% versus 99% (P = .64) in the matched cohort and 97% versus 97%, respectively (P = .30), in the unmatched cohort. Survival at 10 years was 98% after cusp repair and 93% without cusp repair (P = .05).

Conclusions

Aortic valve reimplantation for patients with tricuspid aortic valves has excellent long-term results. Need for aortic valve cusp repair does not affect long-term outcomes and should not deter surgeons from performing valve-sparing surgery.

Management Challenges in Patients Younger Than 65 Years With Severe Aortic Valve Disease

Importance

The management of aortic valve disease, including aortic stenosis and aortic regurgitation (AR), in younger adult patients (age <65 years) is complex, and the optimal strategy is often unclear, contingent on multiple anatomic and holistic factors.

Observations

Traditional surgical approaches carry significant considerations, including compulsory lifelong anticoagulation for patients who receive a mechanical aortic valve replacement (AVR) and the risk of structural valvular deterioration and need for subsequent valve intervention in those who receive a bioprosthetic AVR. These factors are magnified in young adults who are considering pregnancy, for whom issues of anticoagulation and valve longevity are heightened. The Ross procedure has emerged as a promising alternative; however, its adoption is limited to highly specialized centers. Valve repair is an option for selected patients with AR. These treatment options offer varying degrees of durability and are associated with different risks and complications, especially for younger adult patients. Patient-centered care from a multidisciplinary valve team allows for discussion of the optimal timing of intervention and the advantages and disadvantages of the various treatment options.

Conclusions and Relevance

The management of severe aortic valve disease in adults younger than 65 years is complex, and there are numerous considerations with each management decision. While mechanical AVR and bioprosthetic AVR have historically been the standards of care, other options are emerging for selected patients but are not yet generalizable beyond specialized surgical centers. A detailed discussion by members of the multidisciplinary heart team and the patient is an integral part of the shared decision-making process.

Aortic Valve Repair Using HAART 300 Geometric Annuloplasty Ring: A Review and Echocardiographic Case Series

Aortic valve repair (AVr) aims to preserve the native aortic leaflets and restore normal valve function. In doing so, AVr is a more technically challenging approach than traditional aortic valve replacement. Some of the complexity of repair techniques can be attributed to the unique structure of the functional aortic annulus (FAA), which, unlike the well-defined mitral annulus, is comprised of virtual and functional components. Though stabilizing the ventriculo-aortic junction (VAJ), a component of the FAA, is considered beneficial for patients with chronic aortic insufficiency (AI), the ideal AVr technique remains a subject of much debate. The existing AVr techniques do not completely stabilize the VAJ which may increase susceptibility to recurrent AI due to VAJ dilation. An emerging new technique showing promise for the treatment of both isolated and complex AI is AVr using HAART 300^TM geometric annuloplasty ring (GAR). The GAR is implanted below the valve leaflets in the left ventricular outflow tract (LVOT), providing stability and creating a neo-annulus. As with other AVr subtypes, this procedure has a learning curve. There are unique surgical and echocardiographic aspects of AVr with GAR, including the appearance of the LVOT, the aortic valve leaflets, and their motion which cardiac anesthesiologists and echocardiographers must be familiar with. In this work, using an eight-patient echocardiographic case series, we provide an overview of this novel AVr technique, including some unique aspects of device sizing, patient selection, expected post-repair echocardiographic features, and a review of outcomes data.

Geometric characteristics of bicuspid aortic valves

OBJECTIVE

We studied the coaptation angles α and β in bicuspid aortic valve geometry from computed tomography scan images.

METHODS

In 45 patients, we calculated the coaptation angle α (the angle between the nonfused commissures crossing the center of coaptation), angle β (between the nonfused commissures crossing the center of the reference circle), angles γ1 and γ2 and ε1 and ε2 (angle between the nonfused commissures and the coaptation point at the raphe or the perfect midpoint, respectively), the length of the raphe, the absolute and relative sinuses' surfaces (relative to the perfect circle and the percentage exceeding the ideal circle). Spearman correlation was employed to investigate the associations among all parameters.

RESULTS

The coaptation angles α and β were significantly different (P < .001). We found a significant correlation of α with the length of the raphe (P = .008), whereas β was dependent on the position of the commissures. Both γ1 and γ2 (P = .04), or ε1 and ε2 (P < .001) significantly differed from each other and ε2 was the most constant angle, although its size geometrically depends on β. The noncoronary was the largest sinus, and β was the primary determinant of its increased size in bicuspid aortic valves with righ/left fusion pattern.

CONCLUSIONS

The coaptation angle α is influenced by the length of the raphe, whereas angle β is dependent on the position of the commissures. The position of the raphe can vary and is not always situated in the middle of the free edge. The position of the right/non commissure is variable, whereas the right/left commissure is more fixed.

Valvular heart disease in congenital heart disease: a narrative review

Patients with congenital heart disease (CHD) are one of the fastest growing populations in cardiology, and valvular pathology is at the center of many congenital lesions. Derangements in valvular embryology lead to several anomalies prone to dysfunction, each with hemodynamic effects that require appropriate surveillance and management. Surgical innovation has provided new treatments that have improved survival in this population, though has also contributed to esotericism in patients who already have unique anatomic and physiologic considerations. Conduit and prosthesis durability are often monitored collaboratively with general and specialized congenital-focused cardiologists. As such, general cardiologists must become familiar with valvular disease with CHD for appropriate care and referral practices. In this review, we summarize the embryology of the semilunar and atrioventricular (AV) valves as a foundation for understanding the origins of valvular CHD and describe the mechanisms that account for heterogeneity in disease. We then highlight the categories of pathology from the simple (e.g., bicuspid aortic valve, isolated pulmonic stenosis) to the more complex (e.g., Ebstein's anomaly, AV valvular disease in single ventricle circulations) with details on natural history, diagnosis, and contemporary therapeutic approaches. Care for CHD patients requires collaborative effort between providers, both CHD-specialized and not, to achieve optimal patient outcomes.

Intraoperative transesophageal echocardiography in cardiovascular surgery. Consensus document from the Spanish Society of Anesthesia and Critical Care (SEDAR) and the Spanish Society of Endovascular and Cardiovascular Surgery (SECCE)

Transesophageal echocardiography is a semi-invasive technique that allows an evaluation of cardiac morphology and function in real time and it is a quality standard in cardiovascular surgery. It has become a fundamental tool for both monitoring and diagnosis in the intraoperative period that allows decide the correct surgical planning and pharmacological management. The goal of this document is to answer the questions of when and how the perioperative TEE should be performed in cardiovascular surgery, what are their applications in the intraoperative, who should perform it and how the information should be transmitted. The authors made a systematic review of international guidelines, review articles and clinical trials to answer by consensus to these questions.

Timing and mode of intervention for patients with left sided valvular heart disease: an individualized approach

Left sided valvular heart disease poses major impact on life and lifestyle. Medical therapy merely palliates chronic severe valve disease and once symptoms or haemodynamic sequelae appear, life expectancy is markedly truncated. In this article, we review the mechanisms of valve pathology, latest evidence in the quest for pharmacological options, means by which to predict deterioration, and standard and novel treatment options.

Management strategies and future challenges for aortic valve disease

The management of aortic valve disease has been improved by accurate diagnosis and assessment of severity by echocardiography and advanced imaging techniques, efforts to elicit symptoms or objective markers of disease severity and progression, and consideration of optimum timing of aortic valve replacement, even in elderly patients. Prevalence of calcific aortic stenosis is growing in ageing populations. Conventional surgery remains the most appropriate option for most patients who require aortic valve replacement, but the transcatheter approach is established for high-risk patients or poor candidates for surgery. The rapid growth of transcatheter aortic valve replacement has been fuelled by improved technology, evidence-based clinical research, and setting up of multidisciplinary heart teams. Aortic regurgitation can be difficult to diagnose and quantify. Left ventricular dysfunction often precedes symptoms, needing active surveillance by echocardiography to determine the optimum time for aortic valve replacement. Development of transcatheter approaches for aortic regurgitation is challenging, owing to the absence of valvular calcification and distortion of aortic root anatomy in many patients.

Aortic valve repair update

The key for successful valve repair is full understanding of the regurgitant mechanism and sufficient evaluation of the valve. Currently, multidetector computed tomography has been introduced for evaluation. The aortic valve can be analyzed in details preoperatively. The main causes of aortic regurgitation (AR) in the adult population are degenerative leaflet change and annulus dilatation. Restoration to normal structure can be accomplished mainly by plication. Central leaflet plication near the Arantius nodule is a simple technique for redundant tissue. For leaflet deficiency, pericardial patch plasty may be an option. No universal technique exists for plication of the aortic annulus. The valve-sparing aortic root replacement firmly stabilizes the ventriculo-aortic junction (VAJ) and assures repair durability even in patients with mild to moderate root dilatation. Subcommissural annuloplasty (Cabrol stitch) does not seem sufficient for the prevention of VAJ dilatation. Circumferential annuloplasties may have a greater potential. However, convenient device for annular plication is still in development. The bicuspid aortic valve is a congenital heart valve lesion. A basic technique is free margin plication of the fused leaflet. Aortic root dilatation may contribute to AR severity. Valve-sparing aortic root replacement may improve repair durability. Considering the great advances in valve repair, young patients with AR should be informed that valve repair is a promising option for surgical treatment.

3D-echo in preoperative assessment of aortic cusps effective height

Effective height, which represents the height difference between the central free margins and the aortic insertion lines can be easily determined by 2-D echocardiography and allows for identification of prolapse in the native cusps and assessment of prolapse correction after valve repair. Nonetheless, it allows to see only two of three aortic valve (AV) coaptation planes and this may lead to misunderstanding of the underlying pathophysiological mechanism for aortic regurgitation and hence in unsuccessful repair. In contrast, 3D transoesophageal echocardiography and multiple plane reconstruction lets visualize all the three coaptation planes between the AV cusps and it represents an invaluable tool in the assessment of aortic valve geometry. It is highly recommendable before AV repair to accurately study the complex three dimensional cusps anatomy and their geometric interrelation with aortic root.

The role of transesophageal echocardiography in aortic valve preserving procedures

In selected cases of aortic regurgitation, aortic valve (AV) repair and AV sparing root reconstruction viable alternatives to aortic valve replacement. Repair and preservation of the native valve avoids the use of long-term anticoagulation, lowers the incidence of subsequent thromboembolic events and reduces the risk of endocarditis. Additionally repair has a low operative mortality with reasonable mid-term durability. The success and longer term durability of AVPP has improved with surgical experience. An understanding of the mechanism of the AR is integral to determining feasibility and success of an AVPP. Assessment of AV morphology, anatomy of the functional aortic annulus (FAA) and the aortic root with transesophageal echocardiography (TEE) improves the understanding of the mechanisms of AR. Pre- and intra-operative TEE plays a pivotal role in guiding case selection, surgical planning, and in evaluating procedural success. Post-operative transthoracic echocardiography is useful to determine long-term success and monitor for recurrence of AR.

Successful bicuspid aortic valve repair using external aortic annuloplasty

A 33-year-old man presented with severe aortic insufficiency due to a prolapsed bicuspid aortic valve. The ventriculoaortic junction was dilated to 29 mm without root dilatation, and external ring annuloplasty was performed using a Gelweave (Terumo, Tokyo, Japan) graft to reduce the size to 22 mm. The leaflets were repaired by dividing and suturing a raphe between the right and left cusps. This combination provided adequate coaptation depth (8 mm) and showed excellent results, with trivial aortic insufficiency. This approach is suitable for repair of a bicuspid aortic valve with a dilated ventriculoaortic junction without root dilatation.

Aortic valve repair with autologous pericardium for traumatic aortic valve regurgitation

We present a case of successful aortic valve repair for traumatic aortic valve regurgitation. A 26-year-old male who had a history of motor-cycle accident months prior to admission, was referred to our hospital for surgical treatment of severe aortic valve regurgitation. Intraoperative inspection revealed a tear in noncoronary cusp, with otherwise preserved valvular anatomy. Aortic valvuloplasty was successfully performed with closure using an autologous pericardium patch. Intraoperative transesophageal echocardiogram confirmed absence of residual regurgitation.

Systematic Approach to Aortic Valvuloplasty in Children and Young Adults

Valve repair in children and young adults is an attractive alternative to replacement or Ross procedure. In the past, the various valvuloplasty techniques have addressed isolated valve pathology. Recently, however, a holistic approach involving repair of all aortic root structures has evolved and promised to be an excellent alternative to valve replacement. It provides good long-term results and avoids all the drawback of prosthetic valve insertion in this age group. Development of ideal patch material needed for valve repair and better understanding of the anatomy and function of the aortic root may further improve the short- and long-term outcomes of aortic valvuloplasty.

Influence of higher valve gradient on long-term outcome after aortic valve repair

BACKGROUND

To evaluate the effect of higher post-operative valve gradient on freedom from valve re-intervention and death in patients undergoing aortic valve repair (AVr).

METHODS

Patients who underwent AVr between March 1996 and June 2010 were divided into 2 groups: I: peak gradient (PG) <20 mmHg (n=358) and II: PG ≥20 mmHg (n=113). Age (53.6±16.0 vs. 50.6±16.4 years; P=0.08), impaired LV (n=44, 12.2% vs. n=12, 10.6%: P=0.73) as well as the body surface area (1.97 vs. 1.95 m(2); P=0.4) were similar. Pre-operative AI >2+ was greater in Group II compared to Group I (n=78, 69.0% vs. n=192, 53.6%; P=0.004). Patients in Group II had higher proportion of bicuspid valves (BV) (n=58, 51.3% vs. n=106, 29.6%; P=0.0001) and restrictive valves (n=34, 30.0% vs. n=52, 14.5%; P=0.0001) while Marfan patients were seen only in Group I (n=19; P=0.010). Mean follow-up for Group I and Group II was 123.1±89.7 and 147.1±108.0 months, respectively.

RESULTS

In-hospital mortality was n=2 (0.5%) for Group I and none for Group II (P=1.0). Valve-sparing was higher in Group I (P=0.0001) but sub-commissural annuloplasty was similar (P=0.15). Shaving and/or decalcification was performed more in Group II (n=68, 60.1% vs. n=117, 32.6%; P=0.0001). Logistic regression analysis identified calcified, restrictive and bicuspid valves as independent predictors of PG ≥20 mmHg (P=0.04 for each). Predictors of re-operation were increased end-diastolic diameter (P=0.03) and younger age (P=0.007), but not PG ≥20 mmHg (P=0.98) (based on logistic regression). Overall 10-year cardiac survival and freedom from AV re-intervention was 82.3±4.6% vs. 89.5±4.2% (P=0.53) and 89.1±3.0% vs. 76.8±8.4% (P=0.02), in Group I and II, respectively (based on Kaplan-Meier analysis). Sub-group analysis showed that Group II patients requiring re-intervention (n=10) were younger (41.8±13.1 vs. 51.0±16.0 years; P=0.08) with similar proportion of bicuspid valves (n=6; 60%; P=0.74). The main reason for AV re-operation was aortic insufficiency (n=7) and AI + stenosis (n=3).

CONCLUSIONS

Higher gradient after AVr is associated with a reduced freedom from AV re-intervention, especially in younger patients.

Bicuspid aortic valve and aortic root disease

Bicuspid aortic valve (BAV) is the most common form of congenital heart disease, with frequent and premature occurrence of cardiac events, dominated by significant valvular dysfunction. BAV has a high prevalence of aortic wall abnormalities such as ascending aortic dilatation. Because more rapid aortic dilatation can occur, once the ascending aorta reaches 40 mm, annual imaging with echocardiography or other imaging techniques is indicated. The most feared complication is aortic dissection. However, the actual incidence of this complication is low (4%). Although limited data exist regarding prophylactic intervention, it is suggested that elective surgical repair of BAV-associated aortic dilatation should be more aggressively recommended. In patients with BAV, the decision to indicate surgical treatment in aortic diameters between 50 and 55 mm should be based on patient age, body size, comorbidities, type of surgery, and the presence of additional risk factors.

Repair of bicuspid aortic valve with severe regurgitation

To improve the success rate and reproducibility of bicuspid aortic valves, we apply a systematic segmental approach to their repair. A segmental analysis of the morphology is followed by corresponding pathology specific corrections of each morphological abnormality contributing to regurgitation.

Effect of electrical stimulus parameters on the development and propagation of action potentials in short excitable fibres

Intracellular action potentials (IAPs) produced by short fibres in response to their electrical stimulation were analysed. IAPs were calculated on the basis of the Hodgkin-Huxley (1952) model by the method described by Joyner et al. (1978). Principal differences were found in processes of activation of short (semilength L less than 5 lambda) and long fibres under near-threshold stimulation. The shorter the fibre, the lower was the threshold value (Ithr). Dependence of the latency on the stimulus strength (Ist) was substantially non-linear and was affected by the fibre length. Both fibre length and stimulus strength influenced the IAP amplitude, the instantaneous propagation velocity (IPV) and the site of the first origin of the IAP (and, consequently, excitability of the short fibre membrane). With L less than or equal to 2 lambda and Ithr less than or equal to Ist less than or equal to 1.1Ithr, IPV could reach either very high values (so that all the fibre membrane fired practically simultaneously) or even negative values. The latter corresponded to the first origin of the propagated IAP, not at the site of stimulation but at the fibre termination or at a midpoint. The characters of all the above dependencies were unchanged irrespective of the manner of approaching threshold (variation of stimulus duration or its strength). Reasons for differences in processes of activation of short and long fibres are discussed in terms of electrical load and latency. Applications of the results to explain an increased jitter, velocity recovery function and velocity-diameter relationship are also discussed.