INTRODUCTION — Management of bicuspid aortic valve disease in adults includes surveillance of aortic valve dysfunction and the aorta (the aortic root and ascending aorta), timely intervention, treatment of hypertension, measures to address the risk of infective endocarditis, counseling patients on physical activity, and management prior to and during pregnancy. Interventional management of valve disease and aortopathy in adults with bicuspid aortic valve will be discussed here.
Other aspects of management and diagnosis of bicuspid aortic valve in adults are discussed separately:
●(See "Bicuspid aortic valve: General management in adults".)
●(See "Bicuspid aortic valve: Management during pregnancy".)
●(See "Clinical manifestations and diagnosis of bicuspid aortic valve in adults".)
Bicuspid aortic valve in children is discussed separately:
●(See "Valvar aortic stenosis in children" and "Subvalvar aortic stenosis (subaortic stenosis)".)
RATIONALE AND TYPES OF INTERVENTION — Indications for intervention for aortic valve disease and for aortopathy in adults with bicuspid aortic valve have been developed to reduce the risk of adverse outcomes from uncorrected progressive disease while managing the risk associated with intervention through careful timing and selection of procedures. In patients with bicuspid aortic valve, decisions regarding the timing of bicuspid aortic valve intervention and aortic root or ascending aorta surgery are complex, requiring consideration of the aortic valve function, aortic size, and other patient characteristics.
The natural histories of aortic stenosis (AS) and aortic regurgitation (AR) are discussed separately. (See "Natural history, epidemiology, and prognosis of aortic stenosis" and "Natural history and management of chronic aortic regurgitation in adults".)
The natural history of aortopathy in patients with bicuspid aortic valve is discussed below. (See 'Evidence' below.)
Options for intervention depend upon whether the patient with bicuspid aortic valve requires aortic valve intervention, repair of the aorta, or both:
●Patients with indications for intervention for AS or AR without indications for repair of the aorta are candidates for aortic valve intervention without surgery on the aorta. Options for aortic valve intervention are discussed below. (See 'Intervention for aortic stenosis' below and 'Intervention for aortic regurgitation' below.)
●Patients with indications for surgery on the aorta without indications for aortic valve surgery (ie, those with less than moderate AS or AR) are candidates for a valve-sparing procedure (figure 1). Valve-sparing aortic root surgery involves surgical repair of the aortic root and ascending aorta while retaining the native valve and includes the David (reimplantation technique), Yacoub (remodeling technique), and partial Yacoub procedures [1].
●Patients with indications for both aortic valve surgery and repair of the aorta are candidates for combined aortic valve and aortic surgery. This is generally accomplished by surgical aortic valve replacement with concurrent aortic repair. However, there is growing experience with surgical aortic valve repair, rather than replacement, for select cases of AR complicating bicuspid aortic valve [2].
•In patients who require aortic valve replacement and have ascending aortic dilation above the sinotubular junction, a prosthetic aortic valve and a supracoronary aortic polyethylene terephthalate (PET; eg, Dacron) graft are placed.
•In patients who require aortic valve replacement and have dilated aortic roots and ascending aortas, a composite aortic valve and aortic root and ascending aorta graft replacement (modified Bentall procedure) may be performed. The Bentall procedure includes reimplantation of the coronary arteries into the ascending aortic graft (figure 2). The aortic valve prosthesis may be mechanical or biological ("bio-Bentall").
INTERVENTION FOR AORTIC STENOSIS — Timely intervention is indicated for selected patients with bicuspid aortic valve with severe AS to improve clinical outcomes.
Indications — Standard recommendations for aortic valve intervention for severe AS (table 1) apply to patients with bicuspid aortic valve. (See "Indications for valve replacement for high gradient aortic stenosis in adults", section on 'Indications for valve replacement'.)
The symptoms of AS in bicuspid aortic valve are the same as those associated with tricuspid AS and include chest pain or angina, presyncope and syncope, and heart failure, as discussed separately. (See "Clinical manifestations and diagnosis of bicuspid aortic valve in adults", section on 'Valve disease' and "Clinical manifestations and diagnosis of aortic stenosis in adults" and "Natural history, epidemiology, and prognosis of aortic stenosis".)
For symptomatic patients:
●Symptoms by history or on exercise testing caused by severe AS (stage D1) – Valve replacement should be performed promptly after the onset of symptoms.
For asymptomatic patients:
●Severe high-gradient AS and left ventricular ejection fraction (LVEF) <50 percent (stage C2).
●Severe high-gradient AS (stage C) who have a concurrent indication for cardiac surgery.
●Very severe high-gradient AS (stage C) and estimated low procedural risk (for surgical aortic valve replacement [SAVR] or transcatheter aortic valve implantation [TAVI; also known as transcatheter aortic valve replacement or TAVR]).
●Severe high-gradient AS (stage C) and decreased exercise tolerance or fall in systemic blood pressure with exercise.
●Severe AS with rapidly progressive disease (increase in aortic velocity ≥0.3 m per second per year) with estimated low procedural risk (for SAVR or TAVI).
Indications for aortic valve intervention in patients with low-flow, low-gradient AS also apply and are discussed separately. (See "Management and prognosis of low gradient aortic stenosis", section on 'Choice of therapy'.)
Procedures for aortic stenosis — For patients with severe AS requiring valve intervention, the main options are SAVR (mechanical or bioprosthetic) and TAVI. For selected patients (generally <25 years of age) with noncalcified valves and no more than mild aortic regurgitation (AR), balloon aortic valvotomy is an alternative option. (See 'Balloon valvotomy' below.)
When aortic valve intervention is indicated, the need for concomitant prophylactic repair of the aorta is assessed. (See 'Indications for prophylactic repair' below.)
●The choice between SAVR and TAVI is discussed separately. (See "Indications for valve replacement for high gradient aortic stenosis in adults" and "Choice of intervention for severe calcific aortic stenosis".)
●For patients undergoing SAVR, the choice between a mechanical or bioprosthetic valve is discussed separately (see "Choice of prosthetic heart valve for surgical aortic or mitral valve replacement"). For selected patients without annuloaortic ectasia, a pulmonary autograft (Ross procedure) is an alternative to a prosthetic valve. (See 'Ross procedure' below.)
Transcatheter aortic valve implantation — Although bicuspid aortic valve was previously considered an exclusion criterion for TAVI due to technical concerns about elliptical deployment or underdeployment, TAVI has been successfully performed in many patients with this disorder [3-12]. While patients with bicuspid aortic valve were excluded from the pivotal trials for TAVI using balloon-expandable or self-expanding prostheses, observational data are available on TAVI in patients with bicuspid aortic valve (eg, 3 percent of patients had bicuspid aortic valve in a United States registry study including 81,822 patients [12]). In addition, it is frequently difficult to ascertain the number of valve leaflets in the presence of severe calcific stenosis, so many patients with an indeterminate leaflet number likely have congenital bicuspid aortic valve. Data are emerging on the effect of various bicuspid aortic valve phenotypes on TAVI outcome. The choice between SAVR and TAVI for patients with severe AS is discussed separately. (See "Indications for valve replacement for high gradient aortic stenosis in adults" and "Choice of intervention for severe calcific aortic stenosis".)
Observational studies of patients undergoing TAVI have generally found similar one-year mortality rates in patients with bicuspid aortic valve, compared with patients with tricuspid aortic valve [8,9,12]. Although some earlier studies reported high rates of post-TAVI AR in patients with bicuspid aortic valve [9], an analysis of observational data suggested that the risk of post-TAVI AR in patients with bicuspid aortic valve may be mitigated by multislice computed tomography (CT)-based transcatheter heart valve sizing [9].
The following studies were based on data from the Society of Thoracic Surgeons/American College of Cardiology (STS/ACC) Transcatheter Valve Therapy Registry:
●A study analyzed data on 2691 propensity-matched pairs of patients with bicuspid and tricuspid AS undergoing TAVI during 2015 to 2018 [12]. Mortality rates were similar in the two groups at 30 days (2.6 versus 2.5 percent) and one year (10.5 versus 12.0 percent). However, patients with bicuspid AS had higher 30-day stroke rate (2.5 versus 1.6 percent) and procedural complications requiring open heart surgery (0.9 versus 0.4 percent) than those with tricuspid AS. Given the limited data on patient selection for TAVI in this study, the clinical significance of these findings is uncertain. Similar rates of post-TAVI paravalvular AR were identified in patients with bicuspid AS compared with patients with tricuspid disease (2.0 versus 2.4 percent at 30 days and 3.2 versus 2.5 percent at one year) [12].
●A subsequent study analyzed data on 3168 propensity-matched pairs of patients with bicuspid and tricuspid AS with low surgical risk undergoing TAVI during 2015 to 2020 [13]. Mortality rates were similar in the two groups at 30 days (0.9 versus 0.8 percent) and at one year (4.6 versus 6.6 percent). Stroke rates were also similar at 30 days (1.4 versus 1.2 percent) and at one year (2.0 versus 2.1 percent). There were similar rates of procedural complications, valve hemodynamics, and moderate or severe paravalvular leak (3.4 versus 2.1 percent).
●A study compared outcomes in individuals with bicuspid and tricuspid AS undergoing TAVI from 2011 through 2018 [14]. Of 170,959 procedures, 5412 (3.2 percent) were performed for individuals with bicuspid aortic valve. Bicuspid aortic valve patients were significantly younger than those with tricuspid aortic valve. Comparing current-generation TAVI devices with older devices, device success rate was higher (96.3 versus 93.5 percent) and the incidence of moderate or more AR was lower (2.7 versus 14 percent). With current devices, device success rate was slightly lower in bicuspid aortic valve patients compared with those with tricuspid aortic valve (96.3 versus 97.4 percent), with a slightly higher incidence of moderate or severe AR among patients with bicuspid aortic valve (2.7 versus 2.1 percent). A lower one-year adjusted risk of morality (hazard ratio 0.88) was observed for patients with bicuspid aortic valve versus tricuspid aortic valve, and there was no difference in one-year risk of stroke.
The effect of aortic valve morphology on outcomes was assessed in a study of 1034 patients with CT-confirmed bicuspid aortic valve (mean age 74.4 and STS score 3.7 percent) undergoing TAVI with contemporary devices [15]. Mortality at 30 days, one year, and two years was 2.0, 6.7, and 12.5 percent. Two-year mortality was significantly higher in patients with both calcified raphe (moderate or greater) and excess leaflet calcification compared with those with one or none of these features (25.7 versus 9.5 versus 5.9 percent). Patients with both of these morphologic features also had higher rates of aortic root injury, moderate or greater paravalvular regurgitation, and 30-day mortality.
Additional data are needed on TAVI outcomes in patients with bicuspid aortic valve and low surgical risk. A prospective single-arm study evaluated early outcomes following TAVI in 150 patients (mean age 70.3) with bicuspid aortic valve and low surgical risk (mean STS score of 1.4) [16]. The incidence of mortality or disabling stroke was 1.3 percent (one death and one stroke) at 30 days. The device success rate was 95.3 percent. A permanent pacemaker was implanted in 15.1 percent. No patient had greater than mild paravalvular regurgitation. Long-term follow-up is planned.
Ross procedure — The Ross procedure is a potential option for selected patients with bicuspid aortic valve without annuloaortic ectasia requiring valve replacement. The Ross procedure (pulmonary autograft replacement of the aortic valve and homograft valve implantation in the pulmonic position) is a complex procedure to replace the diseased aortic valve and is performed in selected patients at centers of excellence. The procedure is technically challenging, and use of this procedure has declined significantly due to concerns over increased surgical risk and potential long-term failure of the operation. However, with careful patient selection and valve-preserving and autograft-reinforcing/replacement techniques, long-term durability has been reported [17-20]. Specific considerations apply for patients with bicuspid aortic valve [17]:
●For patients with bicuspid aortic valve who have annuloaortic ectasia and AR, the Ross procedure is contraindicated.
●Patients with bicuspid aortic valve with a dilated ascending aorta (>40 mm) without evidence of connective tissue disease or familial aortopathy may be candidates for the Ross procedure but should undergo prophylactic ascending aorta repair at the time of the Ross procedure to stabilize the sinotubular junction and reduce the risk of late pulmonary autograft regurgitation.
Balloon valvotomy — While percutaneous aortic valvotomy is not recommended in the setting of calcific AS in older adults, there is a role for valvuloplasty in selected younger adults. For adults (generally <25 years old) with bicuspid AS with noncalcified valves and no more than mild AR, balloon aortic valvotomy is an alternative option [21,22].
Observational data indicate that balloon valvuloplasty can effectively reduce the aortic valve gradient in selected patients with bicuspid AS without significant aortic valve calcification but commonly causes increased AR. Long-term follow-up (largely in children) has shown that patients commonly require reintervention, as restenosis generally occurs. Limited data are available in adults as most series of bicuspid aortic valve treated with balloon valvotomy included predominantly young children. (See "Subvalvar aortic stenosis (subaortic stenosis)".)
One series described outcomes in 15 patients (aged 16 to 24 years) with congenital AS (bicuspid in 12) who underwent balloon valvotomy [23]. The aortic gradient was not adequately reduced (residual systolic gradient ≥70 mmHg) in three patients. AR was unchanged in nine patients, increased by one grade in four patients, and increased by two grades in two patients. Two patients required valve replacement for AS and one patient required valve replacement four years later for severe AR. At mean 1.5 years follow-up in 13 patients, the aortic valve gradient remained improved.
INTERVENTION FOR AORTIC REGURGITATION — Timely aortic valve intervention is indicated for selected patients with bicuspid aortic valve with severe aortic regurgitation (AR) to improve clinical outcomes.
Indications — Standard recommendations for aortic valve surgery for specific stages of severe AR (table 2) apply to patients with bicuspid aortic valve. (See "Natural history and management of chronic aortic regurgitation in adults", section on 'Indications for aortic valve surgery'.)
For symptomatic patients:
●Severe AR (stage D), regardless of LV systolic function
For asymptomatic patients:
●Severe AR and LVEF <50 percent (stage C2)
●Severe AR, normal LVEF (≥50 percent), and an end-systolic dimension >50 mm (stage C2)
●Severe AR, normal LVEF (≥50 percent, stage C), and progressive severe LV dilation (LVEDD >65 mm), if surgical risk is low
●Moderate AR (stage B) and undergoing other cardiac surgery
Procedures for aortic regurgitation — For patients with bicuspid aortic valve requiring surgery for AR, options include surgical aortic valve replacement (mechanical or bioprosthetic), and, for selected patients with AR caused by aortic cusp prolapse, surgical aortic repair is an alternative option, as described below. (See 'Aortic valve repair' below.)
The choice of valve prosthesis (bioprosthetic versus mechanical) is discussed separately. (See "Choice of prosthetic heart valve for surgical aortic or mitral valve replacement".)
Aortic valve repair — Aortic valve repair may be considered for select cases (ie, significant AR secondary to aortic cusp prolapse) at centers where surgical expertise with this procedure is available [18,24-29]. Using current techniques, many noncalcified bicuspid aortic valves with AR can be preserved or repaired with excellent short-term durability and freedom from valve-related complications if all pathologic components of the aortic valve and root (including annular dilation) are corrected [18]. Valve repair is often performed in conjunction with replacement of the ascending aorta. In a series of 728 patients who underwent bicuspid aortic valve repair, approximately 50 percent of patients had at least moderate AR at five years after repair, and 22 percent of patients underwent aortic valve reoperation by 10-year follow-up [26]. Of 85 valve-sparing root replacements for bicuspid aortic valve aneurysm disease, 99 percent were free of more than moderate AR at eight years [29]. In a series of 40 patients with bicuspid aortic valve and aneurysm disease who underwent valve-sparing root replacements, five-year freedom from more than mild AR or reoperation was 100 percent [27]. In a 20-year series of 357 patients who underwent bicuspid aortic valve repair and aortic root remodeling, the cumulative incidence of moderate or more severe AR at 10 and 15 years was 12 and 17 percent, respectively, and the cumulative incidence of reoperation for aortic valve replacement was 22 percent at 15 years [28]. In a series of patients undergoing valve-sparing root replacement for regurgitant bicuspid aortic valves, the 10-year freedom from reoperation was 90 percent [30].
AORTIC SURGERY
Indications for prophylactic repair — The decision on when to proceed with surgery involves weighing the estimated risk of surgery and the risk of aortic complications (such as aortic dissection and rupture) based upon presence of high-risk features (described below) and the ascending aortic (root or tubular ascending aorta) size. The decision may also take into account other relevant clinical features such as bicuspid aortic valve dysfunction (AS and/or aortic regurgitation [AR]), the patient’s age, aortic size in relation to body size, associated conditions, operative risk, and overall prognosis. However, there is no standard systematic method for integrating such information, and limited data on natural history, including the risk of aortic events at various aortic dimensions in patients with bicuspid aortic valve, are available to guide management. (See 'Evidence' below and "Overview of open surgical repair of the thoracic aorta", section on 'Indications for open repair'.)
The role for adjustment of aortic size for body size is discussed below (see 'Role of adjustment for body size' below). Recommendations for measuring the ascending aorta are discussed separately. (See "Bicuspid aortic valve: General management in adults", section on 'Surveillance'.)
The optimum ascending aortic diameter threshold for prophylactic surgery to repair the aortic sinuses or replace the tubular ascending aorta in patients with bicuspid aortic valve is controversial [31,32]. Our approach to identifying candidates for prophylactic ascending aortic surgery is similar to that in major society guidelines [32-38], including the 2016 statement of clarification from the American College of Cardiology/American Heart Association (ACC/AHA) [34] and the 2018 American Association for Thoracic Surgery (AATS) consensus guidelines [35]. Recommendations for prophylactic aortic surgery are largely based on consensus of expert opinion since only limited observational data are available (algorithm 1) [22,39] (see 'Evidence' below):
●For most patients with bicuspid aortic valve who lack high-risk clinical features, we recommend surgery to repair or replace the ascending aorta at a threshold aortic root or ascending aorta diameter of ≥5.5 cm.
●For most patients with bicuspid aortic valve who have one or more high-risk clinical features or have low estimated surgical risk (<4 percent risk of mortality with the surgery to be performed by an experienced aortic surgical team in a center with established expertise in these procedures), we suggest surgery to repair or replace the ascending aorta at a threshold aortic root or ascending aorta diameter of ≥5.0 cm.
High-risk features are aortic coarctation, aortic root aneurysm phenotype, family history of aortic dissection/sudden death, predominant AR, uncontrolled hypertension, and rapid progression of aortic dilation (defined as an increase of >0.3 cm/year on repeated measurements using the same imaging technique at the same aortic level with side-by-side comparison).
●For patients with an aortic root or ascending aorta diameter of ≥4.5 cm, undergoing cardiac surgery (eg, aortic valve surgery), we suggest aortic surgery in patients with bicuspid aortic valve who are undergoing aortic valve surgery because of severe AS or AR.
Indications for aortic surgery prior to pregnancy in patients with bicuspid aortic valve are discussed separately. (See "Bicuspid aortic valve: Management during pregnancy", section on 'Aortic aneurysm and risk of aortic dissection'.)
The above recommendations are for prophylactic surgery. As discussed separately, patients with aortic dissection involving the ascending aorta or symptoms suggestive of expansion of a thoracic aneurysm should be evaluated for prompt surgical intervention. (See "Management of acute type B aortic dissection" and "Management of thoracic aortic aneurysm in adults".)
Role of adjustment for body size — The risk of thoracic aortic aneurysm rupture and dissection is related not only to aortic size but also to aortic size relative to the patient’s body size [35,39-42]. However, for decision making about prophylactic aortic surgery, consensus is lacking on the value of adjustment for body size and the optimum method for adjustment since most of the available data are based on absolute aortic size. Some studies in patients with dilated ascending aortas and bicuspid aortic valve [39], tricuspid aortic valve [41], or unspecified valve morphologies [40] have found that ascending aortic diameter indexed for body size better predicted adverse aortic events than absolute aortic diameter, but a variety of methods for adjustment have been proposed [35,42].
The 2020 AHA/ACC valvular heart disease writing group recommended not using formulas to adjust the aortic diameter for body size in patients with bicuspid aortic valve [22]. However, the writing groups from the 2010 AHA/ACC thoracic aortic disease guidelines and the 2014 AHA/ACC valvular heart disease guidelines authored a statement of clarification regarding timing of aortic surgery in bicuspid aortic valve disease in 2016 [34]. This updated guideline recognized the potential value of considering body size in the timing of aortic surgery in bicuspid aortic valve disease and in particular, the importance of indexing aortic size to body size in short-statured Turner syndrome patients, a population in whom such indexing predicts aortic risk better than aortic size alone [34] (see "Management of Turner syndrome in adults", section on 'Aortic dilatation'). The 2018 AATS bicuspid aortopathy guidelines discussed various proposed methods for adjusting for body size without endorsing any specific method [35].
Methods for measuring the ascending aorta are discussed separately. (See "Bicuspid aortic valve: General management in adults", section on 'Surveillance'.)
Evidence — Thresholds for prophylactic surgery in patients with bicuspid aortic valve (eg, 5.5 cm or less) are based upon the substantial risk of aortic complications (aortic dissection or rupture) in patients with large ascending aortic aneurysms, the relatively low risk of aortic surgery, and generally good postoperative outcomes. Since aortic dissection also occurs at ascending aortic diameters <5.5 cm, prophylactic surgery is performed at lower thresholds in patients with high-risk features, when the ascending aorta size is rapidly expanding, or when surgery can be performed at a low risk by an experienced surgical team at a center with experience in these procedures. The aortic root phenotype is one of the high-risk features, as it is associated with more rapid growth and higher risk of aortic events, especially after isolated aortic valve replacement [1,43,44]. (See 'Postoperative outcomes' below.)
Data on the risk of aortic complications in patients with bicuspid aortic valve are limited since most published studies of aortic complications in patients with bicuspid aortic valve have included patients treated with elective aortic surgery for aortic dilation [45-48]. A series from the Cleveland Clinic reported a 4.1 percent risk-adjusted probability of acute aortic dissection when the bicuspid aortic valve aortic aneurysm was 5 cm in the sinuses of Valsalva and a 3.8 percent risk-adjusted probability of acute aortic dissection when the aneurysm size was 5.3 cm in the ascending aorta [39]. In this study, aortic cross-sectional area to height ratio was a better predictor of aortic dissection than aortic diameter. Follow-up studies of patients with bicuspid aortic valve (with baseline proximal aortic diameter generally ≤50 mm) undergoing isolated aortic valve replacement surgery have yielded disparate results, though overall a <1 percent per year rate of aortic complications [45,46].
Thus, the threshold for aortic surgery in patients with bicuspid aortic valve is largely based upon natural history data for thoracic aortic aneurysms generally. Support for using a similar surgical threshold in patients with bicuspid aortic valve, as for other patients with ascending aortic aneurysm, comes from limited data showing generally comparable rates of aortic rupture and dissection in these populations [49]. The rate of thoracic aortic expansion in patients with bicuspid aortic valve has been reported to be similar to or slightly greater than that seen in patients with tricuspid aortic valve with ascending aortic dilation (excluding patients with connective tissue disorders such as Marfan syndrome) [48-52]. In a retrospective observational study comparing echocardiograms at least two years apart, the maximal aortic dilation rate in patients with bicuspid aortic valve (0.42±0.6 mm/year) was similar to that among those with Marfan syndrome (0.49±0.5 mm/year) and higher than that seen with degenerative aortopathy (0.20±0.3 mm/year) [53]. A large, contemporary series of nonsyndromic patients with aortic dilation found that female sex and presence of bicuspid aortic valve were independent risk factors for aortic expansion [54]. Baseline aortic diameter and age (but not presence of bicuspid aortic valve) were independent predictors of aortic dissection or rupture. (See "Epidemiology, risk factors, pathogenesis, and natural history of thoracic aortic aneurysm and dissection", section on 'Natural history'.)
An ascending aortic diameter threshold of 5.5 cm for elective aortic surgery is based upon the following studies in patients with ascending aortic aneurysms. These studies did not specifically examine bicuspid aortic valve aneurysms. A study of 133 patients found that the five-year risk of rupture was 0 percent for aneurysms less than 4.0 cm, compared with 16 and 31 percent for aneurysms 4.0 to 5.9 and ≥6.0 cm, respectively [55]. In another series of 370 patients, the median diameter at the time of rupture or dissection was 5.9 cm for ascending aneurysms and 7.2 cm for descending aneurysms; a diameter greater than 6.0 cm increased the risk of rupture or dissection by 25 percent for an ascending aneurysm, while a diameter greater than 7.0 cm increased the risk by 37 percent in a descending aneurysm [56]. In a prospective study of 721 patients, the rates of dissection or rupture were 2, 3, and 7 percent per year for aneurysms less than 5.0 cm, 5.0 to 5.9 cm, and ≥6.0 cm, respectively [57]. Among patients with aneurysms ≥6.0 cm, the combined endpoint of rupture, dissection, or death occurred at a rate of 15.6 percent per year. The five-year rate of survival in patients with aneurysms >6.0 cm was 56 percent. In patients who did not undergo surgery (diameter not specified), 54 percent were alive at five years. By comparison, elective surgery restored survival to a rate similar to a matched control population. (See "Management of thoracic aortic aneurysm in adults".)
Although the dissection rate increases with aortic diameter, most patients who present with acute aortic dissection have smaller aneurysms because there are many more individuals in the population with thoracic aortic aneurysm diameters between 4.0 and 5.5 cm. This was demonstrated in a review of 591 patients with type A dissection (mean diameter 5.3 cm) enrolled in the International Registry of Acute Aortic Dissection (IRAD) [58]. Nearly 60 percent of patients had diameters <5.5 cm, and 40 percent had aortic diameters <5.0 cm. Current recommendations for elective surgery include patients with ascending aortic aneurysm size between 5.0 to 6.0 cm. (See "Management of thoracic aortic aneurysm in adults".)
Postoperative outcomes — Expected mortality rates and the potential for continued aortic dilation over time are important considerations in management of the ascending aorta. Late complications depend upon the surgical procedure performed: aortic valve intervention without surgery on the aorta, valve-sparing operations, or combined aortic valve and ascending aorta surgery.
A systematic review of 32 observational studies reported outcomes for 9441 adults with bicuspid aortic valve and 1605 control subjects [45]. The 30-day mortality rate after aortic valve replacement and/or aortic surgery was 0 to 2.5 percent. There were slightly higher rates of bleeding and reexploration in patients undergoing both aortic valve replacement and proximal aortic surgery as compared with isolated aortic root surgery. Reported long-term outcomes included all-cause mortality and acute aortic event rate (need for subsequent proximal aortic surgery, aortic dissection/rupture, or sudden death not attributable to any other cause) for each of three groups of patients:
●For nonoperated bicuspid aortic valve patients (ages 30 to 40 years old):
•The annualized mortality rate was 0.56 percent (95% CI 0.13-0.99).
•The annualized acute aortic event rate was 0.29 percent (95% CI 0.23-0.35), which was not significantly different from the rate for patients with a tricuspid aortic valve.
●For patients who had undergone proximal aortic surgery (generally at ages 40 to 60 years old):
•The annualized mortality rate was 0.78 percent (95% CI 0.20-1.36).
•The annualized acute aortic event rate was 0.16 percent (95% CI 0.0-0.32).
●For patients who had undergone isolated aortic valve replacement (>60 years old):
•The annualized mortality rate was 2.39 percent (95% CI 1.61-3.16).
•The annualized acute aortic event rate was 0.68 percent (95% CI 0.42-0.94).
Among patients with bicuspid aortic valve undergoing isolated aortic valve replacement, the risk of late aortic complications is greater in patients with larger baseline aortic size and in patients with the aortic root phenotype and for those who underwent valve replacement for predominant AR [43,44], as illustrated by the following studies:
●A series of 201 patients (mean age 56 years) with bicuspid aortic valve (63 percent had AS, 22 percent had AR, and 15 percent had mixed disease) underwent isolated aortic valve replacement between 1979 and 1993 at Toronto General Hospital [59]. Late aortic aneurysm formation depended upon the aortic size at the time of valve replacement. During mean 10.3-year follow-up, 18 patients (9 percent) required late aortic replacement for aneurysm at mean diameter of 5.8 cm. Survival was 67 percent at 15 years. Freedom from ascending aortic complications at 15 years (aneurysm repair, dissection, or sudden death) was 78 percent for initial aortic size <4 cm; 81 percent for aortic size 4 to 4.4 cm; and 43 percent for aortic size 4.5 to 4.9 cm.
●A study of 1286 patients (mean age 58 years) with bicuspid aortic valve (92 percent with AS, 7 percent with AR) who underwent isolated aortic valve replacement between 1960 and 1995 at the Mayo Clinic reported 12-year median follow-up [60]. Survival was 52 percent at 15 years. Freedom from ascending aortic complications was 89 percent at 15 years. Aortic dissection occurred in 13 patients (1 percent), while aortic dilation (aortic diameter >5.0 cm or >1.0 cm growth after valve replacement) occurred in 127 (10 percent).
●Long-term survival was higher in a later study of 153 bicuspid aortic valve patients (mean age 54 years) with AS and ascending aortic dilation of 40 to 50 mm who underwent isolated aortic valve replacement between 1995 and 2001 at the Central Clinic Bad Berka [44]. Actuarial survival was 78 percent for the AS group at 15 years. Freedom from adverse aortic events at 10 and 15 years was 95 and 93 percent, respectively. This study also included outcomes for a separate group of 21 bicuspid aortic valve patients (mean age 41 years) with aortic valve regurgitation and predominant dilation of the aortic root (root phenotype) who underwent isolated aortic valve replacement. In this group, the freedom from adverse aortic events at 10 and 15 years was 88 and 70 percent, respectively. Thus, patients with the root phenotype were at increased risk for adverse aortic events, as has also been suggested by other observations.
MONITORING AFTER AORTIC VALVE SURGERY OR AORTA REPAIR
After aortic valve surgery — Since late complications after bicuspid aortic valve replacement include aortic dissection/rupture and ascending aortic aneurysm formation with need for subsequent proximal aortic surgery, monitoring with aortic imaging is recommended in bicuspid aortic valve patients late after valve replacement. Serial monitoring of prosthetic valves is discussed separately. (See "Overview of the management of patients with prosthetic heart valves", section on 'Serial follow-up'.)
Patients who have undergone aortic valve replacement without ascending aorta repair should continue surveillance of the ascending aorta. (See "Bicuspid aortic valve: General management in adults", section on 'Surveillance'.)
Patients who have undergone aortic valve repair should be followed postoperatively with yearly echocardiograms as recommended in the 2013 Society of Thoracic Surgeons (STS) guidelines [24].
Management and complications after transcatheter aortic valve implantation are discussed separately. (See "Transcatheter aortic valve implantation: Complications" and "Transcatheter aortic valve implantation: Periprocedural and postprocedural management".)
After ascending aorta repair — Surgical repairs of the ascending aorta are generally durable, with most anastomotic problems occurring early in the postoperative period. Thus, postoperative imaging is generally required only if a problem is suspected. If there is residual aortic dilation or other pathology, imaging of the entire aorta every three to five years after aortic surgery by magnetic resonance imaging (MRI) or computed tomography (CT) is suggested [35]. However, many surgeons will routinely obtain MRI or CT scans at three- to five-year follow-up to look for proximal or distal anastomotic pseudoaneurysms. (See "Management of thoracic aortic aneurysm in adults".)
Serial imaging following surgical or endovascular intervention for aortic dissection is discussed separately. (See "Management of acute type A aortic dissection", section on 'Serial imaging' and "Management of acute type B aortic dissection", section on 'Surveillance imaging'.)
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Bicuspid aortic valve" and "Society guideline links: Cardiac valve disease" and "Society guideline links: Aortic dissection and other acute aortic syndromes" and "Society guideline links: Congenital heart disease in adults".)
SUMMARY AND RECOMMENDATIONS
●Indications for intervention for aortic valve disease and for aortopathy in adults with bicuspid aortic valve have been developed to reduce the risk of adverse outcomes from uncorrected progressive disease while managing the risk associated with intervention through careful timing and selection of procedures. In patients with bicuspid aortic valve, decisions regarding the timing of bicuspid aortic valve intervention and aortic root or ascending aorta surgery are complex, requiring consideration of the aortic valve function, aortic size, and other patient characteristics. (See 'Rationale and types of intervention' above.)
●Options for intervention depend upon whether the patient with bicuspid aortic valve requires aortic valve intervention, repair of the aorta, or both. (See 'Rationale and types of intervention' above.)
●Standard recommendations for aortic valve intervention for severe aortic stenosis (AS) and for severe aortic regurgitation (AR) apply to patients with bicuspid aortic valve. (See 'Intervention for aortic stenosis' above and 'Intervention for aortic regurgitation' above.)
●For patients with severe AS requiring valve intervention, the main options are surgical aortic valve replacement (mechanical or bioprosthetic) and transcatheter aortic valve intervention. For selected patients (generally <25 years of age) with noncalcified valves and no more than mild AR, balloon aortic valvotomy is an alternative option. (See 'Procedures for aortic stenosis' above.)
●For patients with bicuspid aortic valve requiring surgery for AR, the main options are surgical aortic valve replacement (mechanical or bioprosthetic) and, for selected patients with AR caused by aortic cusp prolapse, surgical aortic repair is an alternative option. (See 'Procedures for aortic regurgitation' above.)
●The decision on when to proceed with aortic surgery involves weighing the estimated risk of surgery and the risk of progressive aortic disease based upon risk factors and the ascending aortic (root or tubular ascending aorta) diameter. The decision may also take into account other clinical features such as patient age and aortic size in relation to body size. Recommendations for prophylactic aortic surgery are largely based on consensus of expert opinion, as limited data are available (see 'Indications for prophylactic repair' above and 'Evidence' above):
•For most patients with bicuspid aortic valves who lack high-risk clinical features, we recommend surgery to repair or replace the ascending aorta at a threshold aortic root or ascending aorta diameter ≥5.5 cm (Grade 1B).
•For most patients with bicuspid aortic valve who have one or more high-risk clinical features or have low estimated surgical risk (<4 percent with the surgery to be performed by an experienced aortic surgical team in a center with established expertise in these procedures), we suggest surgery to repair or replace the ascending aorta at a threshold aortic root or ascending aorta diameter of ≥5.0 cm (Grade 2C). High-risk features include aortic coarctation, aortic root aneurysm phenotype, family history of aortic dissection/sudden death, predominant AR, uncontrolled hypertension, and rapid progression of aortic dilation (defined as an increase of >0.3 cm/year on repeated measurements using the same imaging technique at the same aortic level with side-by-side comparison).
•For patients with an aortic root or ascending aorta diameter ≥4.5 cm undergoing cardiac surgery (eg, aortic valve surgery), we suggest aortic surgery in patients with bicuspid aortic valve who are undergoing aortic valve surgery because of severe AS or AR (Grade 2C).
●The risk of thoracic aortic aneurysm rupture and dissection is related not only to aortic size but also to the aortic size relative to the patient’s body size. However, for decision making about prophylactic aortic surgery, consensus is lacking on the value of adjustment for body size and the optimum method for adjustment, since most of the available data are based on absolute aortic size. (See 'Role of adjustment for body size' above.)
●The patient with a bicuspid aortic valve undergoing isolated aortic valve replacement should continue to undergo surveillance of the aortic root and ascending aorta after surgery. (See 'Monitoring after aortic valve surgery or aorta repair' above and "Bicuspid aortic valve: General management in adults", section on 'Surveillance'.)
ACKNOWLEDGMENT — The editorial staff at UpToDate acknowledges Martin G Keane, MD, FACC, FAHA, FASE, Thomas P Graham, MD, and Catherine M Otto, MD, who contributed to an earlier version of this topic review.
The editorial staff would also like to acknowledge Martin St. John Sutton, MD (deceased), who contributed to an earlier version of this topic review.
