Aortic stenosis valvuloplasty
Aortic Stenosis Microchapters |
Diagnosis |
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Treatment |
Percutaneous Aortic Balloon Valvotomy (PABV) or Aortic Valvuloplasty |
Transcatheter Aortic Valve Replacement (TAVR) |
Case Studies |
Aortic stenosis valvuloplasty On the Web |
American Roentgen Ray Society Images of Aortic stenosis valvuloplasty |
Directions to Hospitals Treating Aortic stenosis valvuloplasty |
Risk calculators and risk factors for Aortic stenosis valvuloplasty |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Joanna J. Wykrzykowska, M.D.; Associate Editor(s)-In-Chief: Mohammed A. Sbeih, M.D. [2]
Overview
Although surgical aortic valve replacement is the mainstay of treatment of aortic stenosis as it improves both symptoms and life expectancy, some patients may not be surgical candidates due to comorbidities, and minimally invasive treatment such as percutaneous aortic balloon valvotomy (PABV) maybe an alternative to surgery as a palliative strategy. PABV is a procedure in which 1 or more balloons are placed across a stenotic valve and inflated to decrease the severity of aortic stenosis. This is to be distinguished from transcatheter aortic valve implantation (TAVI) which is a different method that involves replacement of the valve percutaneously.
Indications
- Surgical aortic valve replacement is the treatment of choice for aortic stenosis but many patients are not good candidates due to advanced age and multiple co-morbidities.
- Percutaneous aortic valve replacement is in its infancy and thus aortic valvuloplasty can offer palliation of symptoms and potentially prolong survival for these high risk patients in class III-IV heart failure
- It can be performed emergently in patients with end-stage heart failure due to aortic stenosis: patients in cardiogenic shock, as a bridge to aortic valve replacement, patients with critical aortic stenosis needing emergent non-cardiac surgery, poor surgical candidates and nonagenerians, patients with congenital or rheumatic aortic stenosis
- Results usually last 6 months up to 2 years (with repeat procedures possible if aortic regurgitation is not severe)
- Valvuloplasty tends to alleviate heart failure symptoms and improve hemodynamics but rarely does it alleviate angina
- ACC/AHA guidelines concluded that percutaneous aortic balloon valvotomy (PABV) is not a substitute for aortic valve replacement in adults. In adults with severe calcific AS who are not good candidates for this procedure as there is high restenosis rate (more than 10% of cases) and high risk of complications. Clinical deterioration occur within 6 to 12 months in most patients, and that is why balloon valvotomy is not a substitute for aortic valve replacement surgery. The procedure can be used in children and young adults with congenital, noncalcific AS.
ACC/AHA Guidelines- Indications for Percutaneous Aortic Balloon Valvotomy (DO NOT EDIT) [1]
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Class IIb1. Aortic balloon valvotomy might be reasonable as a bridge to surgery in hemodynamically unstable adult patients with AS who are at high risk for AVR. (Level of Evidence: C) 2. Aortic balloon valvotomy might be reasonable for palliation in adult patients with AS in whom AVR cannot be performed because of serious comorbid conditions. (Level of Evidence: C) Class III1. Aortic balloon valvotomy is not recommended as an alternative to AVR in adult patients with AS; certain younger adults without valve calcification may be an exception. (Level of Evidence: B) |
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ACC/AHA 2008 Guidelines- Recommendations for Catheter Interventions for Adults With Valvular Aortic Stenosis (DO NOT EDIT)
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Class I1. In young adults and others without significantly calcified aortic valves and no AR, aortic balloon valvotomy is indicated in the following patients: a. Those with symptoms of angina, syncope, dyspnea on exertion, and peak-to-peak gradients at catheterization greater than 50 mm Hg. (Level of Evidence: C) b. Asymptomatic adolescents or young adults who demonstrate ST or T-wave abnormalities in the left precordial leads on ECG at rest or with exercise and a peak-to-peak catheter gradient greater than 60 mm Hg. (Level of Evidence: C) Class III1. In older adults, aortic balloon valvotomy is not recommended as an alternative to AVR, although certain younger patients may be an exception and should be referred to a center with experience in aortic balloon valvuloplasties. (Level of Evidence: B) 2. In asymptomatic adolescents and young adults, aortic balloon valvotomy should not be performed with a peak-to-peak gradient less than 40 mm Hg without symptoms or ECG changes. (Level of Evidence: B) Class II a1. Aortic balloon valvotomy is reasonable in the asymptomatic adolescent or young adult with AS and a peak-to-peak gradient on catheterization greater than 50 mm Hg when the patient is interested in playing competitive sports or becoming pregnant. (Level of Evidence: C) Class II b1. Aortic balloon valvotomy may be considered as a bridge to surgery in hemodynamically unstable adults with AS, adults at high risk for AVR, or when AVR cannot be performed secondary to significant comorbidities. (Level of Evidence: C) |
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ACC/AHA 2008 Guidelines- Recommendations for Aortic Valve Repair/Replacement and Aortic Root Replacement (DO NOT EDIT)
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Class I1. Aortic valvuloplasty, AVR, or Ross repair is indicated in patients with severe AS or chronic severe AR while they undergo coronary artery bypass grafting surgery on the aorta, or surgery on other heart valves. (Level of Evidence: C) 2. AVR is indicated for patients with severe AS and LV dysfunction (LV ejection fraction less than 50%). (Level of Evidence: C) 3. AVR is indicated in adolescents or young adults with severe AR who have: a. Development of symptoms. (Level of Evidence: C) b. Development of persistent LV dysfunction (LV ejection fraction less than 50%) or progressive LV dilatation (LV end-diastolic diameter 4 standard deviations above normal). (Level of Evidence: C) 4. Surgery to repair or replace the ascending aorta in a patient with a BAV is recommended when the ascending aorta diameter is 5.0 cm or more or when there is progressive dilation at a rate greater than or equal to 5 mm per year.73 (Level of Evidence: B) Class III1. AVR is not useful for prevention of sudden death in asymptomatic adults with AS who have none of the findings listed under the Class IIa/IIb indications. (Level of Evidence: B) 2. AVR is not indicated in asymptomatic patients with AR who have normal LV size and function. (Level of Evidence: B) Class IIa1. AVR is reasonable for asymptomatic patients with severe AR and normal systolic function (ejection fraction greater than 50%) but with severe LV dilatation (LV end-diastolic diameter greater than 75 mm or end-systolic dimension greater than 55 mm*). (Level of Evidence: B) 2. Surgical aortic valve repair or replacement is reasonable in patients with moderate AS undergoing coro- nary artery bypass grafting or other cardiac or aortic root surgery. (Level of Evidence: B) Class IIb1. AVR may be considered for asymptomatic patients with any of the following indications: a. Severe AS and abnormal response to exercise. (Level of Evidence: C) b. Evidence of rapid progression of AS or AR. (Level of Evidence: C) c. Mild AS while undergoing coronary artery bypass grafting or other cardiac surgery and evidence of a calcific aortic valve. (Level of Evidence: C) d. Extremely severe AS (aortic valve area less than 0.6 cm and/or mean Doppler systolic AV gradient greater than 60 mm Hg) in an otherwise good operative candidate. (Level of Evidence: C) e. Moderate AR undergoing coronary artery bypass grafting or other cardiac surgery. (Level of Evidence: C) f. Severe AR with rapidly progressive LV dilation, when the degree of LV dilation exceeds an end-diastolic dimension of 70 mm or end-systolic dimension of 50 mm, with declining exercise tolerance, or with abnormal hemodynamic response to exercise. (Level of Evidence: C) 2. Surgical repair may be considered in adults with AS or AR and concomitant ascending aortic dilatation (ascending aorta diameter greater than 4.5 cm) coexisting with AS or AR. (Level of Evidence: B) 3. Early surgical repair may be considered in adults with the following indications: a. AS and a progressive increase in ascending aortic size. (Level of Evidence: C) b. Mild AR if valve-sparing aortic root replacement is being considered. (Level of Evidence: C) |
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Percutaneous Aortic Balloon Valvotomy (PABV) Technique
- After preparing the patient, a guide wire is inserted through the femoral artery into the aorta (retrograde technique). 8 French femoral sheath can usually accommodate a 20 mm balloon and minimizes vascular complications. Alternatively two 6 Fr sheath from bilateral femoral approach and two smaller balloons can be used. the latter may be necessary in female elderly patients with concomitant peripheral vascular disease.
- 0.035” straight wire is commonly used to cross the valve and advance via pig-tail or Amplatz catheter; right heart catheterization is done and transaortic gradient is typically measured pre-procedure. The 0.035” wire is then exchanged for a stiffer 0.038”Amplatz exchange length wire with the tip shaped into a pig-tail shape so as not to injure the left ventricle.
- A long sheath is introduced over the guide wire, through the sheath a Mansfield balloon is introduced and 20-23 mmX 6 cm balloon is advance over the wire and positioned to straddle the aortic valve.
- The balloon is manually inflated with a 60 cc syringe containing diluted contrast (slowly). Meticulous control of balloon position must be maintained at all times by backward traction on the balloon to prevent jumping forward and injuring/perforating the left ventricular apex.
- If there is difficulty in maintaining the balloon across the aortic valve during inflation, temporary ventricular pacing at high rate can reduce the cardiac output and give stability to the balloon.
- Balloon is deflated and the trans valvar gradient reassessed for success of the procedure. Repeated dilatations can be given if necessary.
- The balloon should be de-aired and filled with dilute contrast to avoid the chance of air embolism in case of balloon rupture during dilatation.
Outcome
- Immediately after the procedure a moderate reduction in the transvalvular pressure gradient is usually observed. The aortic valve area after the procedure rarely exceeds 1.0 cm2 but an early symptomatic improvement is usually observed.
- Patient survival after repeat PABV is higher than that of untreated patients.
Complications
- Vascular complications are most common thus suture (Perclose) or Angioseal closure after the procedure in this tenuous patient population is preferable.
- It follows that attention to meticulous access technique is mandatory.
- Antegrade approach ie venous access with transseptal approach can be done in select patients, however, hemodynamic effects of mitral valve incompetence as a stiff wire is placed across the mitral valve are often poorly tolerated; mitral valve injury has been reported in this approach.
- There is a small but significant risk of development of aortic regurgitation as a result of the procedure which can lead to pulmonary edema.
- The balloon may rupture while dilation of a calcified valve is performed.
Sources
- 2008 Focused Update Incorporated Into the ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease [1].
References
- ↑ 1.0 1.1 Bonow RO, Carabello BA, Chatterjee K, de Leon AC, Faxon DP, Freed MD; et al. (2008). "2008 focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to revise the 1998 guidelines for the management of patients with valvular heart disease). Endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons". J Am Coll Cardiol. 52 (13): e1–142. doi:10.1016/j.jacc.2008.05.007. PMID 18848134.