*3.13.7.1 Low-flow, low-gradient aortic valve*

The precise assessment within the heart team of the pathology and anatomy, as well as the evaluation of the patient, are emphasised in the new graduated recommendations regarding low-flow, low-gradient aortic valve stenosis in symptomatic patients [60].

It is also highly recommended to take into account the morphology of the device landing zone and the resulting individual risks for TAVI procedures.

For asymptomatic patients with an indication for aortic valve replacement, surgical replacement is still the gold standard, because no data are available for this patient cohort concerning TAVI treatment.

### *3.13.7.2 Management of aortic regurgitation*

Surgical aortic valve replacement remains the standard gold treatment of aortic valve regurgitation (AR). Transcatheter aortic valve implantation (TAVI) plays only a minor role. Currently, the JenaValve (JenaValve Technology GmbH, Munich, Germany) is the only prosthesis available for pure AR as an investigational device [61]. All other prostheses are used off label [61]. Concerning the choice of the type of prosthesis, criteria used in aortic stenosis are not merely interchangeable. The percentage of oversizing has to be calculated in a different way because of the absence annular calcification. Although outcomes have improved with newer-generation TAVI devices outcomes are still inferior to surgery. In a few circumstances, TAVI might be an option for patients with severe AR and high surgical risk.

The class I recommendations for aortic valve intervention, in patients with AR according to the 2014 American College of Cardiology and the American Heart Association are the following: symptomatic patients with chronic severe AR, asymptomatic patients with chronic severe AR and LV dysfunction (ejection fraction < 50%) at rest, and patients with chronic severe AR who are undergoing concomitant coronary artery bypass grafting, aortic surgery, or other heart valve surgery.

The class IIa recommendation is for patients with asymptomatic AR and normal LV systolic function (ejection fraction > 50%) but with severe LV dilation (endsystolic diameter > 50 mm). The class IIb recommendation is for patients with moderate AR who are undergoing coronary artery bypass grafting, aortic surgery, or other heart valve surgery. Aortic valve intervention may also be reasonable in asymptomatic patients with chronic severe AR, normal LV systolic function, and severe LV dilation (end-diastolic diameter > 65 mm) if the operative risk is low. Other considerations can include evidence of progressive LV dilation, declining exercise tolerance, or abnormal hemodynamic response to exercise [62, 63].

However, aortic valve repair carries a similar, if not lower, risk of perioperative complication with a low risk of valve-related events over time. Similar to mitral valve repair for mitral regurgitation, six there is some suggestion that aortic valve intervention should be considered earlier in patients in whom aortic valve repair is likely [64].

Another broad category of patients who undergo aortic valve preservation and repair are those with primary aortic pathology involving the aortic root or the ascending aorta and varying degrees of associated aortic valvular disease. In these patients, the primary indication for intervention is driven by aortic size, discussed in the American, European, and Canadian Guidelines.

From a technical perspective, all patients with primary aortic insufficiency are potential candidates for repair. However, the success of aortic valve repair is determined largely by the quality of cusp tissue available. Thus, patients with significant leaflet calcification, destruction owing to active endocarditis, or rheumatic involvement are least likely to undergo successful and durable aortic valve repair. In contrast, repair has been shown to have good results in patients with bicuspid (and in smaller series, unicuspid, and quadricuspid aortic valves), despite the abnormalities in cusp anatomy. An important limitation to the universal application of aortic valve repair techniques is the lack of surgical expertise and experience in this field; however, this is changing rapidly with increasing interest in aortic valve repair. Patients who are candidates for repair should be referred to centres with appropriate expertise.

**31**

**Figure 4.**

*Aortic valve replacement.*

*Aortic Valve Disease: State of the Art*

already requiring cardiac surgery.

*3.13.7.3 Procedures*

*DOI: http://dx.doi.org/10.5772/intechopen.93311*

Surgery of the aortic valve can now be accomplished with greater safety and efficacy in the majority of patients. In patients with higher operative risks, TAVI is already a proven acceptable alternative to AVR. The choice of valve prosthesis is guided by patient preference, life expectancy, and comorbidities relevant to SVD and anticoagulation. Aortic valve repair in the young patient with AR avoids the risks associated with valve prostheses, but long-term durability is unknown. Aortic root surgery similarly can be performed with the replacement of both the aortic valve and aortic wall, but valve-sparing techniques may offer the advantage of durability equivalent to that of normal native aortic valves with avoidance of prosthetic valve-related complications. Reoperative aortic valve and aortic root surgery, like isolated AVR, can be performed safely with best outcomes at high-volume centres. Aortic valve replacement (AVR) is becoming safe despite the elderly population of patients is now being treated, with the best outcomes achieved at high-volume centres. The standard approach is a median sternotomy aortic valve and aortic root replacement. However, minimally invasive approaches, including the upper hemisternotomy and right anterior thoracotomy (**Figure 4**), can be performed with equivalent safety and better outcomes. The use of stented bioprosthetic valves surpassed the use of mechanical valves, homografts, and pulmonary autografts combined, reflecting advances in valve technology. The Novel Sutureless valves combine the advantages of a surgical AVR procedure (control of aortic atheroemboli, resection of the diseased native valve) with transcatheter technique (decreased procedure time, improved valve hemodynamic function). Bentall procedure: root replacement with a composite valve-graft is the gold standard for aortic root aneurysm (**Figure 5**). However, for patients who want to avoid the long-term oral anticoagulation required for mechanical valves and structural valve deterioration of the bioprosthetic valves, valve-sparing aortic root replacement (David or Yacoub procedures) is a good option (**Figure 6**). Indications for aortic root replacement include aneurysms of the ascending aorta, aortic valve endocarditis with annular abscess, and acute type A aortic dissection. The most common indication is an aneurysm of the aortic root or ascending aorta. The size threshold for aneurysm repair depends on whether the aneurysm is the primary indication for surgery or whether it coexists in a patient
