Authors: Anna Hartzog MD and Chinwe Unegbu MD – Children’s National Hospital
A 1-day old neonate with critical aortic stenosis and decreased left ventricular function is intubated due to respiratory failure, pulmonary edema and increasing left atrial pressures. The patient presents to the operating room for surgical repair. What is the GREATEST benefit of a surgical aortic valve repair over aortic balloon valvuloplasty?
Correct!
Wrong!
Question of the Week 345
Congenital aortic stenosis occurs in approximately 6% of patients with congenital heart disease. While valvar aortic stenosis is most common, stenosis can occur at the subvalvar, valvar, or supravalvar level. Valvar aortic stenosis is more common in males, and is often associated with a bicuspid aortic valve, coarctation of the aorta, patent ductus arteriosus, and ventricular septal defect. Unicuspid aortic valve is most often associated with critical aortic stenosis. If not recognized early, neonates with severe aortic stenosis can present with congestive heart failure, arrhythmias, lactic acidosis, cardiogenic shock, and even sudden death.
The size and function of the left ventricle is the main determinant for appropriateness of a single-ventricle versus a biventricular repair. Measurements that predict a favorable two-ventricle repair include aortic annulus ≥ 3.0 cm/m2, aortic root ≥ 3.5 cm/m2, mitral valve area ≥ 4.75 cm2/m2, ratio of long axis of the left ventricle to the heart ≥0.8, and left ventricular cross-sectional area ≥ 2.0 cm2. The most common interventions which preserve biventricular anatomy include balloon aortic valvuloplasty (BAV) and surgical aortic valvotomy (SAV). The goal of either intervention is to reduce the aortic valve gradient and prevent aortic regurgitation.
BAV is performed in the cardiac catheterization lab. The aortic valve can be approached via the femoral, umbilical, or carotid arteries. It is recommended to use a balloon with a balloon to aortic valve annulus ratio of 0.8 to 1.0 to avoid over-dilation, which can result in significant aortic insufficiency (AI). A unicuspid aortic valve morphology is not always amenable to BAV due to increased risk of AI. After BAV, an immediate reduction in the peak pressure gradient across the valve is typically seen. The degree of immediate post-valvuloplasty insufficiency is predictive of late onset AI and suggests the likelihood for re-intervention.
SAV is performed in the operating room with cardiopulmonary bypass, cardioplegia, and hypothermic myocardial protection. Early surgical techniques for SAV were associated with roughly 50% mortality. However, advancements in surgical technique have improved mortality to a 100% 10-year survival. If not amenable to SAV, a valve replacement with a prosthetic or allograft valve may be performed. Alternatively, the Ross procedure may be performed in which the patient’s pulmonary valve replaces the aortic valve. Prerequisites to the Ross procedure include a normal right ventricular outflow tract and pulmonary valve. The disadvantage of the the Ross procedure is the risk of future aortic and pulmonary valve disease.
Early studies demonstrated equivocal outcomes in terms of survival and the need for re-intervention when comparing SAV and BAV. Advancements in surgical technique have demonstrated improved outcomes after SAV in more recent studies. In a study by Siddiqui et al, freedom from re-intervention at five years was 65% after SAV compared to 27% after BAV. Similar results were demonstrated in a meta-analysis by Hill et al in which BAV resulted in reduced gradient reduction, increased AI post-procedure, and greater need for subsequent intervention compared to SAV. Additionally, there was no difference in long-term survival and freedom from aortic valve replacement between the two groups, thus answer A is incorrect. The study also demonstrated a greater rate of additional intervention in the BAV group.
A study by Hermann et al demonstrated that SAV resulted in greater gradient reduction, reduced long-term AI, and a lower re-intervention rate at 10 years compared to BAV. However, SAV has been associated with higher morbidity and longer hospital stay compared to BAV. Studies have demonstrated no difference in mortality between the two groups. As a result, in this question the correct answer is C because there is less long-term aortic insufficiency in the SAV group. There is no difference in survival or rate of valve replacement between the two groups. Patients undergoing SAV require a longer hospital stay.
References:
Spaeth JP and Loepke AW. Anesthesia for Left-sided Obstructive lesions. In: Andropoulos, D, Stayer S, Mossad EB, Miller-Hance WC. Anesthesia for Congenital Heart Disease. Third Edition. Hoboken, New Jersey: John Wiley & Sons, Inc. 2015, 497-515.
Singh, G. Congenital Aortic Valve Stenosis. Children (Basel). 2019; 6(5): 69. doi: 10.3390/children6050069
Herrmann JH, Clark AJ, Colgate C, et al. Surgical valvuloplasty versus balloon dilation for congenital aortic stenosis in pediatric patients. World J Pediatr Congenit Heart Surg. 2020; 11(4): 444-451. doi:10.1177/2150135120918774.
McCrindle B, Blackson EH, Williams WG, et al. Are outcomes of surgical versus transcatheter balloon valvotomy equivalent in neonatal critical aortic stenosis? Circulation. 2001; 104: I152-158.
Siddiqui J, Brizard CP, Galati JC, et al. Surgical valvotomy and repair for neonatal and infant congenital aortic stenosis achieves better results than interventional catheterization. J Am Coll Cardiol. 2013; 62(22): 2134-2140. doi:10.1016/j.jacc.2013.07.052.
Hill G, Ginde S, Rios R, Frommelt PC, Hill KD. Surgical valvotomy versus balloon valvuloplasty for congenital aortic valve stenosis: A systematic review and meta-analysis. J Am Heart Assoc. 2016; 5(8): e003931. doi: 10.1161/JAHA.116.003931.
Brown J, Rodefeld MD, Ruzmetov M, Eltayeb O, Yurdakok, Turrentine MW. Surgical valvuloplasty versus balloon aortic dilation for congenital aortic stenosis: Are evidence-based outcomes relevant? Ann Thorac Surg. 2012; 94(1): 146-153. doi:10.1016/j.athoracsur.2012.02.054.
The size and function of the left ventricle is the main determinant for appropriateness of a single-ventricle versus a biventricular repair. Measurements that predict a favorable two-ventricle repair include aortic annulus ≥ 3.0 cm/m2, aortic root ≥ 3.5 cm/m2, mitral valve area ≥ 4.75 cm2/m2, ratio of long axis of the left ventricle to the heart ≥0.8, and left ventricular cross-sectional area ≥ 2.0 cm2. The most common interventions which preserve biventricular anatomy include balloon aortic valvuloplasty (BAV) and surgical aortic valvotomy (SAV). The goal of either intervention is to reduce the aortic valve gradient and prevent aortic regurgitation.
BAV is performed in the cardiac catheterization lab. The aortic valve can be approached via the femoral, umbilical, or carotid arteries. It is recommended to use a balloon with a balloon to aortic valve annulus ratio of 0.8 to 1.0 to avoid over-dilation, which can result in significant aortic insufficiency (AI). A unicuspid aortic valve morphology is not always amenable to BAV due to increased risk of AI. After BAV, an immediate reduction in the peak pressure gradient across the valve is typically seen. The degree of immediate post-valvuloplasty insufficiency is predictive of late onset AI and suggests the likelihood for re-intervention.
SAV is performed in the operating room with cardiopulmonary bypass, cardioplegia, and hypothermic myocardial protection. Early surgical techniques for SAV were associated with roughly 50% mortality. However, advancements in surgical technique have improved mortality to a 100% 10-year survival. If not amenable to SAV, a valve replacement with a prosthetic or allograft valve may be performed. Alternatively, the Ross procedure may be performed in which the patient’s pulmonary valve replaces the aortic valve. Prerequisites to the Ross procedure include a normal right ventricular outflow tract and pulmonary valve. The disadvantage of the the Ross procedure is the risk of future aortic and pulmonary valve disease.
Early studies demonstrated equivocal outcomes in terms of survival and the need for re-intervention when comparing SAV and BAV. Advancements in surgical technique have demonstrated improved outcomes after SAV in more recent studies. In a study by Siddiqui et al, freedom from re-intervention at five years was 65% after SAV compared to 27% after BAV. Similar results were demonstrated in a meta-analysis by Hill et al in which BAV resulted in reduced gradient reduction, increased AI post-procedure, and greater need for subsequent intervention compared to SAV. Additionally, there was no difference in long-term survival and freedom from aortic valve replacement between the two groups, thus answer A is incorrect. The study also demonstrated a greater rate of additional intervention in the BAV group.
A study by Hermann et al demonstrated that SAV resulted in greater gradient reduction, reduced long-term AI, and a lower re-intervention rate at 10 years compared to BAV. However, SAV has been associated with higher morbidity and longer hospital stay compared to BAV. Studies have demonstrated no difference in mortality between the two groups. As a result, in this question the correct answer is C because there is less long-term aortic insufficiency in the SAV group. There is no difference in survival or rate of valve replacement between the two groups. Patients undergoing SAV require a longer hospital stay.
References:
Spaeth JP and Loepke AW. Anesthesia for Left-sided Obstructive lesions. In: Andropoulos, D, Stayer S, Mossad EB, Miller-Hance WC. Anesthesia for Congenital Heart Disease. Third Edition. Hoboken, New Jersey: John Wiley & Sons, Inc. 2015, 497-515.
Singh, G. Congenital Aortic Valve Stenosis. Children (Basel). 2019; 6(5): 69. doi: 10.3390/children6050069
Herrmann JH, Clark AJ, Colgate C, et al. Surgical valvuloplasty versus balloon dilation for congenital aortic stenosis in pediatric patients. World J Pediatr Congenit Heart Surg. 2020; 11(4): 444-451. doi:10.1177/2150135120918774.
McCrindle B, Blackson EH, Williams WG, et al. Are outcomes of surgical versus transcatheter balloon valvotomy equivalent in neonatal critical aortic stenosis? Circulation. 2001; 104: I152-158.
Siddiqui J, Brizard CP, Galati JC, et al. Surgical valvotomy and repair for neonatal and infant congenital aortic stenosis achieves better results than interventional catheterization. J Am Coll Cardiol. 2013; 62(22): 2134-2140. doi:10.1016/j.jacc.2013.07.052.
Hill G, Ginde S, Rios R, Frommelt PC, Hill KD. Surgical valvotomy versus balloon valvuloplasty for congenital aortic valve stenosis: A systematic review and meta-analysis. J Am Heart Assoc. 2016; 5(8): e003931. doi: 10.1161/JAHA.116.003931.
Brown J, Rodefeld MD, Ruzmetov M, Eltayeb O, Yurdakok, Turrentine MW. Surgical valvuloplasty versus balloon aortic dilation for congenital aortic stenosis: Are evidence-based outcomes relevant? Ann Thorac Surg. 2012; 94(1): 146-153. doi:10.1016/j.athoracsur.2012.02.054.
