Management of 2-Year-Old with Hypertrophic Cardiomyopathy and Severe Aortic Stenosis
This child requires urgent mechanical aortic valve replacement combined with septal myectomy performed at a comprehensive pediatric cardiac center. 1
Rationale for Combined Surgical Intervention
This 2-year-old presents with a life-threatening dual pathology creating compounded left ventricular outflow tract obstruction from both fixed valvular stenosis (68% aortic stenosis) and dynamic obstruction from hypertrophic cardiomyopathy. 1 The presence of increasing dyspnea during physical activity indicates hemodynamic compromise requiring definitive surgical correction rather than temporizing measures. 1
The combination of symptomatic obstructive hypertrophic cardiomyopathy with concurrent valvular aortic stenosis requiring surgical treatment necessitates surgical myectomy combined with valve replacement to correct all structural and anatomic issues with a single procedure. 2, 1
Why Other Options Are Inadequate:
Reassurance is inappropriate and dangerous. 1 The natural history of untreated severe aortic stenosis in children includes sudden death risk and progressive heart failure, with survival worse than many cancers when left untreated. 1 This child already demonstrates symptomatic deterioration with exertional dyspnea, indicating advanced disease. 1
Activity restriction alone does not address the underlying severe aortic stenosis. 2, 1 While appropriate for managing stable hypertrophic cardiomyopathy symptoms, this child already has symptoms at baseline activity levels, and restriction does nothing to treat the fixed 68% valvular stenosis. 1 Medical therapy with beta-blockers or calcium channel blockers is appropriate for obstructive HCM without valvular pathology, but cannot address fixed valvular stenosis. 1
TAVR is contraindicated in this pediatric patient. 1 TAVR durability remains uncertain and is particularly problematic in a child with decades of life expectancy. 1 Additionally, TAVR does not address the septal hypertrophy requiring myectomy. 1
Surgical Approach for Pediatric Patients
The modified Konno procedure provides equally satisfactory long-term results for basal obstruction in young children with small aortic annuli, allowing for aortic valve replacement while simultaneously addressing septal hypertrophy. 2, 1 The classic transaortic septal myectomy approach may be limited in infants and young children where the aortic annulus is small. 2
Transaortic septal myectomy adds minimal risk to other cardiac procedures, and relief of left ventricular outflow tract obstruction minimizes the risk of hemodynamic instability postoperatively. 2, 1
Post-Operative Management Algorithm
Immediate Post-Operative Period:
- Intraoperative transesophageal echocardiography to assess adequacy of septal myectomy and valve function 1
- Beta-blocker therapy to manage residual hypertrophic cardiomyopathy symptoms and reduce arrhythmia risk 1
Follow-Up Surveillance:
- Transthoracic echocardiography within 3-6 months to evaluate procedural results 1
- Serial echocardiography every 1-2 years to monitor for residual obstruction, valve function, and progression of hypertrophy 1
- Continued restriction from competitive sports given the underlying hypertrophic cardiomyopathy diagnosis 2, 1
Critical Pitfalls to Avoid
Do not delay surgical referral for medical optimization. 1 Medical management alone does not address fixed valvular stenosis, and mechanical valve replacement is typically preferred in young patients to avoid multiple reoperations. 1
Do not attempt isolated balloon valvuloplasty. 2 This addresses only the valvular component while leaving the septal hypertrophy untreated, and recurrence is common late after valvotomy. 2
Ensure referral to a comprehensive pediatric cardiac center with documented expertise in both congenital aortic stenosis and hypertrophic cardiomyopathy. 2, 1 The literature demonstrates a volume-outcome relationship, with the highest success rates and lowest complication rates at experienced centers. 2