 Greetings and welcome. My name is Annette Vegas. This session is on the bicuspid aortic valve, the role of TEE in surgical decision-making. I have no conflict of interest. During this talk, we will review the recent consensus classification for the congenital bicuspid aortic valve and its aortopathy. Explain the key anatomic features that determine success of bicuspid aortic valve repair. Review the echo assessment for bicuspid aortic valve repair and show some clinical examples. The number of cusps can vary for the aortic valve. Most cusps, most valves have three cusps, but two, one and even four cusps may be present. Each valve, with an abnormal number of cusps, has associated morbidity and specific echo findings. This talk will focus on the bicuspid aortic valve. Key numbers regarding the epidemiology of the bicuspid aortic valve include a prevalence of one to two percent in the general population, depending on whether autopsy, echo or clinical studies are cited. A three to one gender bias, being more common in males. Abnormal genetic findings occur as it is familial in nine percent of patients. It is recommended that first order relatives be screened. It is the most common congenital heart lesion worldwide, comprising 75% of all lesions and causes more morbidity and mortality than all other congenital lesions combined. Bicuspid aortic valve can be broadly categorized into three clinical prognostic subgroups, uncomplicated, typical, or complex. Uncomplicated is a retrospective diagnosis, as disease is silent and the patients are asymptomatic. So in typical, aortic valve function generally deteriorates over time, causing a valvelopathy, aortic stenosis, aortic regurgitation, mixed, or even endocrinitis. In addition, up to 30% of patients have an aortopathy, presenting with an aortic dilatation or more acutely with aortic dissection. Patients managed appropriately have a normal life expectancy in this group. In the minority of circumstances, patients may be complex with associated lesions that may be even more severe. The other congenital lesions associated with bicuspid aortic valve include syndromes such as Turner's and Williams. Coarctation is present in 7 to 10% of adults with bicuspid aortic valve, whereas bicuspid aortic valve is present in 50 to 60% of patients with coarctation. Other problems with aorta may include sinus aval salva aneurysm in 15 to 20% of patients and supervalvular aortic stenosis. PDA occurs in a known number of patients. Patients may have abnormal coronary anatomy, a non-dominant right, or coronaries adjacent to commissures. VSD and Shown Complex. The morphology of the bicuspid valve is the form and structure. The genetic material creates specific phenotypes or characteristics or traits. The morphology of the bicuspid valve varies resulting in different phenotypes that relate to, one, the orientation of the open casps, two, the position of the commissures, and three, the presence or absence of a rabbi. The caspenslinuses are often asymmetric in size. Though several classification systems describe the bicuspid valve, the most often used is a severs classification. This classification categorizes the bicuspid valve into three subtypes based on the number of rabbi present. Type 0, no rabbi, 6%. Type 1, 1 rabbi, 89%. And type 2, 2 rabbi, 5%. This is often considered the unicuspid valve. Type 1 is the commonest and is further subdivided by the spatial position of the casps into left-right coronary cusp fusion, 71%, right non-coronary cusp fusion, 15%, and non-left coronary cusp fusion, 3%. Shown here are the TEE, midisophageal aortic valve, short-axis views of different bicuspid valves based on the severs classification. Type 0, type 1, type 2. There is an associated systolic doming of the conjoined casps seen in the midisophageal aortic valve, long-axis view. Often, after making this diagnosis, this is where we stop and inform the surgeon. But what additional information will the surgeons require if they want to repair the defective valve? This brings us to the recent consensus classification published in 2021. This is an imaging-based, descriptive, comprehensive nomenclature and classification system that uses the English language and not numbers or letters. It is based on anatomical, clinical, surgical, and pathological scientific data. There are three types, fused, to sinus, and form frustrate. Within each type, there are further phenotypes, which we will explore in the next few slides. The commonest type is the fused bicuspid valve, occurring 90 to 90% of the time. The two cuffs are co-joined, like the severs type 1 classification, with phenotypes being right-left, 70 to 80%, right-non, 20 to 30%, and the least common, left-non, 3 to 6%. As shown here, the cuffs are of different sizes. There are three sinuses, and a raffae can be identified in the conjoined cuffs. As we will see, the commissural angle of the non-fused cusp is an important determinant of repairability. The two sinus bicuspid valve is uncommon, presenting in 5 to 7% of cases. The valve comprises two similar-sized cuffs with only two aortic sinuses. The commissures are positioned at 180 degrees. No raffae is present. In the lower TE example, what is the red arrow pointing to? This is a sinus of valve salve aneurysm of the non-cornery sinus. The other type is the form frustrate bicuspid valve. This valve has partial fusion of less than 50% of the cusp, creating a mini raffae. The valve appears to have re-symmetric cuffs, which create a triangular opening during systole. The commissural angles are at 120 degrees. While functionally normal, in appearance, the partial cusp fusion alters blood flow through the valve. Aortic dilatation may occur in 20 to 30% of patients with bicuspid aortic valve. Aortic expansion in bicuspid valves occurs at a rate of approximately 0.4 to 0.6 mm per year and is age-dependent. The consensus paper describes three aortic phenotypes, one ascending 70%, root 20% and three extended to involve the arch. The size of the aorta can be described as being mild, moderate or severe, depending on the measured size as indicated here. Patients with severe dilatation greater than 55 mm and those with more than 50 mm and risk factors should be considered for surgery. The different types of bicuspid valve aortopathy result in different aortic phenotypes. The commonest, the ascending aorta phenotype, involves dilatation beyond the STJ and occurs in older patients with aortic stenosis. Flow dynamics as shown here relate it most commonly with right non cusp fusion. The root phenotype, on the other hand, involves primarily dilatation of the sinuses, annulus and minimal dilatation of the ascending aorta. Presentation is often in the young male patient with aortic insufficiency. This type is more prone to aortic dissection. Flow hemodynamics relate those most closely with the right left cusp fusion. Here are TE examples of ascending aorta and aortic root dilatation. Accurate and more reliable measurements of aortic diameters at any level are best obtained with CT or MRI. As it is often hard to get truly perpendicular alignment with TE, so CT assessment is important. Aortic dissection is a known complication of bicuspid valve aortopathy occurring in 5% of patients over their lifetime. It is independent of aortic diameter. Regurgitant bicuspid valves are associated with a higher clinical risk for aortic dissection. The functioning cusps of most bicuspid valves exhibit asymmetric systolic excursion with marked bending strain insistently. This creates uneven systolic flow patterns and intrinsic morphological stenosis, such that bicuspid valves, even without calcification, may exhibit a small increase in trans aortic peak velocity. Bicuspid valve aortic stenosis from secondary calcification is the commonest pathology, presenting typically in older patients age 50 to 70 years old and is the indication for aortic valve replacement. Surgery is indicated for the usual indications. There is some debate as to whether tauve is an option. Newer technology and delivery systems may have made it increasingly an option after careful consideration in older patients. Bicuspid valve aortic insufficiency occurs less often in 30% of patients and is more frequent in men. The most important mechanisms of AI are cusp prolapse of the conjoined cusp or both cusps. Annular dilatation and root and STJ dilatation. The determination of AI severity and management follows current guidelines. The current guidelines recommend aortic valve intervention for symptomatic patients with left ventricular systolic dilatation and impaired function. The latter is a key determinant of survival and functional status after aortic valve replacement. In asymptomatic patients or those with moderate disease, the decision to intervene considers several factors, including aortic valve anatomy, aortic root size and shape, regurgitant severity, other comorbidities, and the patients' preferences and values. In asymptomatic patients, left ventricular end diastolic diameter is an important marker of clinical outcome. Intervening in bicuspid valve aortic top of the depends on size and the presence of these risk factors as listed here. Surgical options include traditional aortic valve replacement, replacing portions of the order combined with valve and aortic replacement, sparing the native valve, the ROS procedure, or isolated aortic valve repair. For optimal results, the latter three options should be performed at a center of surgical excellence. As we have seen, not all bicuspid valves are the same. Whether the surgeon can spare the bicuspid valve depends in large part on the cusp's aortic root geometry. The repair-orientated bicuspid valve classification is based on commissure orientation of the non-fuse cusp. The more symmetric type is easiest to repair. The asymmetric type, moderately difficult to repair, and the very asymmetric with commissural angles approximating the tricuspid valve, the most difficult. This animated video contains a commissure angle of 120 degrees. In a very asymmetric type 1 bicuspid aortic valve, the commissure angle is increased to 130 degrees while the fusion length increases and the commissural height decreases. The asymmetric bicuspid aortic valve has a commissure angle around 150 degrees and even more cusp fusion and lower commissure height. The symmetric bicuspid aortic valve has a commissure angle of 170 degrees, nearly fused cusps, and minimal commissure height. Finally, a completely symmetric sievers type 0 bicuspid aortic valve is displayed with a commissure angle of 180 degrees, complete cusp fusion, and only two commissures. Echocardiography plays a critical role in assessing feasibility of repair by identifying cusp phenotype, cusp condition, and measuring the commissural angle. This paper by Michelini is a worthy read on how to assess the bicuspid valve. The minisolphegeal aortic valve short axis view identifies the cusp phenotype as fused to sinus or form frustrate. The presence of three sinuses are confirmed. There may be asymmetry of the cusps and sinuses. A raffae is identified which may be calcified. Characteristics of a bicuspid valve amenable to repair include no or minimal valve calcification and good cusp mobility. An important determinant of the suitability of repair is the commissural angle of the non-fused cusp. This is measured in diastole to identify the non-fused commissures. Draw a line from the commissure to the center of the valve. Measure the angle where these lines intersect. The valve can thus be described by the commissural angle as being symmetric, asymmetric, or very asymmetric. The closer this angle is to 180 degrees, the better chance of successful repair. In addition, root measurements are important to correct the geometry of the valve. The annulus measured during systole should be less than 25 millimeters. The effective height measured in diastole from the annulus to the free margin should be at least 9 millimeters. The geometric height of the non-fused cusp traced in diastole from the cusp insertion point to the free margin in a bicuspid valve should be at least 20 millimeters. These measurements are detailed in these two papers and will be discussed further during the panel discussion. From a basic anesthesia perspective, the goal in bicuspid aortic valve repair is to correct the underlying cause of aortic insufficiency, be it cusp prolamps or abnormal aortic geometry. To optimize the commissure orientation to near 180 degrees. To improve cusp mobility by removing the raffa. To improve geometric and effective cusp height by placating prolapsing cusps and reducing redundant tissue to increase cusp coaptation. Cases with annular dilatation of greater than 27 millimeters require a correction by annular plasticity as this affects the geometric cusp height and length of cusp coaptation. The main aim is to make the commissure at 180 degrees and increase the geometric cusps lies to improve coaptation. Assessment post valve spearing shows a slightly thickened root. Assessment of cusp coaptation is critical. Ideally this cusp should co-op above the annulus without any portion of the cusp prolapsing below the annular plane. The highest point of co-optation is in the mid sinuses. Effective cusp height is the difference between the highest co-optation point and the annulus and should be at least nine millimeters. The co-optation length should be at least five millimeters. The valve is assessed for competency as well as global and regional function of the left ventricle. The presence of new regional wall motion abnormalities may reflect a problem with coronary blood flow. Now let's look at some cases. The first is a 33 year old female who is asymptomatic and presents with severe AI and a dilated left ventricle. The midisophageal aortic valve short axis view shows the presence of a fused bicuspid valve with fused right and left cusps creating asymmetric cusps, three sinuses and a raffae. The midisophageal aortic valve long axis view shows severe AI and the red arrow indicates prolapse of the fused cusp. So how repairable is this valve? There is fusion of right left cusps, asymmetric cusps, three sinuses, a long raffae and minimal calcium on the valve. The commissural angle is asymmetric at 155 degrees. There is prolapse of the fused cusp with eccentric AI. The annulus is measured at 38 millimeters insistently. The effective height is 7.5 millimeters. The commissural height is 5.5 millimeters. The geometric height of the non-fused cusp is 22.8 millimeters. The surgeon went ahead and spare the valve, which involved excising the raffae, implanting a 34 millimeter Dachron graph with subaortic annular plastic, orientating the commissures close to 180 degrees, flicating the fused cusp and reinforcing both cusp margin. The results show valve co-optation above the annulus, co-optation height of 9 millimeters, and a similar effective height. Trivial AI and a commissural angle close to 180 degrees. Case two is a 40 year old male who is asymptomatic with severe AI and a dilated left ventricle similar to the previous patient. The midisophageal aortic valve short axis view confirms the presence of a fuse bicuspid valve with fusion of the right and left cusps, creating asymmetric cusps, three sonuses, and no raffae. The midisophageal aortic valve long axis views show severe posteriorly directed AI, and the red arrow indicates prolapse of the fused cusp. So how repairable is this valve? There is fusion of the right, left cusps, asymmetric cusps, three sonuses, no raffae, and minimal calcium on the valve. The commissural angle is symmetric at 170 degrees. There is prolapse of the fuse cusp with eccentric AI. The annulus measures 27 millimeters insistently. The effective height of the non-fused cusp is 0.5 millimeters. The commissural height is 0, as there is no co-optation. The geometric height of the non-fused cusp is estimated to be only 14 millimeters. The surgeon went ahead and spare the valve, which involved implanting a 32 millimeter Dachron graph, placating the fuse cusp, and equalizing both cusp heights. The results show moderate eccentric and truly directed AI due to retraction of the fuse cusp. The surgeon went back on pump to revise the repair. The final echo shows co-optation above the annulus with a co-optation length of 7.3 millimeters and a similar effective height. The commissural angle is close to 180 degrees, and there is mild AI. The third and final case is a 68-year-old male who presents with a bicuspid aortic valve, ascending aorta dilatation of 55 millimeters, significant triple vessel coronary disease, and a left ventricular ejection fraction of 40 percent. The valve is sporadic with a mean gradient of 15 millimeters of mercury and mild AI. What operation should the patient have? These are the choices, ACB, ACB and hemiarch, ACB-bental and hemiarch, ACB-valves bearing, or just the hemiarch. Congratulations to those who chose number two. The patient underwent a successful operation, ACB and hemiarch. So in summary, the bicuspid aortic valve is a heterogeneous disease. Echocardiography is key to diagnosis and guide surgery. The new bicuspid valve classification facilitates assessment for repairability. Valve sparing procedures require surgical expertise. Thank you very much.