Should I seek immediate evaluation by an interventional cardiologist due to systemic hypoperfusion and low stroke volume index despite a normal ejection fraction?

Immediate Evaluation by Interventional Cardiologist

You should seek urgent—not necessarily emergent—evaluation by a structural/interventional cardiologist within 1-2 weeks, as your combination of systemic hypoperfusion symptoms with severely reduced stroke volume index (23.96 ml/m²) and normal ejection fraction (60-65%) represents paradoxical low-flow severe aortic stenosis, a high-risk condition that requires specialized assessment and likely intervention. 1, 2

Why Your Situation is Critical Despite Normal EF

Your cardiologist's dismissal of stroke volume index was a significant error. The ACC and ESC guidelines explicitly state that SVI <35 ml/m² defines a low-flow state that carries independent prognostic significance, and your value of 23.96 ml/m² falls well below the critical mortality threshold of 30 ml/m². 1, 2, 3 Each 5 ml/m² reduction below normal values increases mortality risk substantially. 1

The paradox here is that your ejection fraction appears "normal" at 60-65%, but this is misleading because:

• Your left ventricle is likely small, thick-walled, and operating with restrictive physiology—it's ejecting a normal percentage of a severely reduced volume. 2, 4
• This represents maladaptive remodeling with progressive diastolic dysfunction, high afterload, and reduced systemic arterial compliance. 4
• Approximately one-third of severe AS cases present this way, and it carries mortality risk comparable to classical low-flow AS with reduced ejection fraction. 2, 5

Why You're Still Functioning (For Now)

You're able to maintain a relatively normal lifestyle because:

• Your body has compensated through increased systemic vascular resistance and other mechanisms to maintain blood pressure despite severely reduced forward flow. 4
• The restrictive physiology develops gradually, allowing some physiologic adaptation. 2, 4
• However, this compensation is precarious—patients with paradoxical low-flow AS can deteriorate rapidly once symptoms develop. 2

The critical point: your current functional status does not reflect the severity of your hemodynamic compromise. Patients with your SVI level have significantly reduced 5-year survival even when asymptomatic. 1, 3

What Needs to Happen Next

Immediate Diagnostic Workup (Within 1-2 Weeks)

1. Comprehensive echocardiographic re-evaluation by an experienced sonographer, specifically measuring: 6, 1

• Aortic valve area (AVA) and indexed AVA
• Peak velocity and mean gradient across the aortic valve
• Left ventricular outflow tract (LVOT) diameter using multiple methods to exclude measurement error
• Left ventricular volumes, wall thickness, and relative wall thickness
• Careful assessment for concomitant mitral regurgitation, which can falsely lower calculated stroke volume 6, 4

2. Aortic valve calcium scoring by cardiac CT—this is essential in your case: 1, 2, 7

• Men: ≥3000 Agatston units confirms severe AS
• Women: ≥1600 Agatston units confirms severe AS
• This definitively distinguishes true severe AS from pseudosevere AS when flow is low and gradients are deceptively modest. 2, 7

3. Consider dobutamine stress echocardiography if there's uncertainty about stenosis severity: 1, 7

• Assesses flow reserve and contractile reserve
• Helps distinguish true severe from pseudosevere AS
• May not be feasible if restrictive physiology is severe 2

Critical Diagnostic Pitfalls to Avoid

Your case exemplifies the most common errors in AS assessment: 6, 2

• Relying solely on ejection fraction to assess cardiac function—EF is preserved in paradoxical low-flow AS despite severely compromised hemodynamics. 1, 2
• Dismissing low gradients as indicating "moderate" stenosis—in low-flow states, gradients severely underestimate anatomic severity because less flow generates lower pressure gradients even when the valve opening is critically small. 6, 2
• Accepting AVA calculations without verifying LVOT measurements—2D echo frequently underestimates LVOT diameter in small hypertrophied ventricles, leading to overestimation of stenosis severity. 2

Management Algorithm Based on Findings

If Severe AS is Confirmed (AVA ≤1.0 cm², indexed AVA ≤0.6 cm²/m², high calcium score):

For symptomatic patients (which you appear to be with systemic hypoperfusion): 6, 1

• Aortic valve replacement is a Class I indication (strongly recommended) regardless of gradient level. 6, 1
• Either surgical AVR or transcatheter AVR (TAVR) depending on surgical risk assessment 6, 1
• Medical management alone is rated "Rarely Appropriate" for symptomatic severe AS. 1

For truly asymptomatic patients with paradoxical low-flow AS: 2

• Intervention is Class IIa (should be considered) after careful confirmation of severity 2
• Close surveillance every 6 months with serial echocardiography 2
• Exercise stress testing to detect early symptoms 2
• However, your SVI of 23.96 ml/m² carries independent prognostic significance even if asymptomatic, as it falls well below the 30 ml/m² mortality threshold. 1, 3

If Moderate AS is Confirmed:

• Aggressive blood pressure control is essential—hypertension significantly worsens outcomes in AS 4
• Regular follow-up every 6-12 months 6
• Symptom monitoring with low threshold for intervention if symptoms develop 6

Why an Interventional/Structural Cardiologist Specifically

You need someone with expertise in: 6, 1

• Complex AS assessment including low-flow states
• Multimodality imaging interpretation (echo, CT, possibly cardiac MRI)
• Risk stratification for intervention timing
• TAVR evaluation if surgical risk is elevated
• Understanding that your normal EF does not mean normal cardiac function—your severely reduced SVI indicates critical hemodynamic compromise. 1, 2

Bottom Line

Your severely reduced stroke volume index of 23.96 ml/m² represents a critical finding that should never have been dismissed. This value, combined with systemic hypoperfusion symptoms and normal EF, defines paradoxical low-flow severe AS until proven otherwise. 1, 2 The fact that you're currently functioning relatively well is due to compensatory mechanisms that can fail suddenly. Seek evaluation by a structural/interventional cardiologist within 1-2 weeks for comprehensive assessment including aortic valve calcium scoring, which will definitively determine whether you need urgent valve intervention. 1, 2, 7