What valvulopathy causes cardiac insufficiency with preserved ejection fraction (EF)?

Aortic Stenosis is the Primary Valvulopathy Causing Cardiac Insufficiency with Preserved Ejection Fraction

Aortic stenosis (AS) is the main valvular heart disease that causes cardiac insufficiency while maintaining a preserved ejection fraction, primarily through diastolic dysfunction and increased left ventricular end-diastolic pressure. 1

Pathophysiology of Aortic Stenosis with Preserved EF

• In AS, the obstruction develops gradually over decades, allowing the left ventricle to adapt through a hypertrophic process that increases LV wall thickness while maintaining normal chamber volume 1
• The increased relative wall thickness counters high intracavitary systolic pressure, keeping LV systolic wall stress (afterload) within normal range, thus preserving ejection fraction 1
• As a result of increased wall thickness, low volume/mass ratio, and diminished compliance, LV end-diastolic pressure increases without chamber dilatation, reflecting diastolic dysfunction rather than systolic dysfunction 1
• This pattern creates what's known as "paradoxical" low-flow, low-gradient AS with preserved EF, typically seen in elderly patients with hypertrophied, small ventricles 1

Clinical Manifestations and Diagnosis

• Patients with severe AS and preserved EF often present with:

  • Dyspnea on exertion 1
  • Heart failure symptoms despite normal ejection fraction 2
  • Reduced stroke volume index (<35 mL/m²) despite normal EF 1
  • Mean gradient typically between 30-40 mmHg (lower than classic severe AS) 1
  • Aortic valve area ≤0.8 cm² 1

• Diagnostic criteria for paradoxical low-flow, low-gradient AS with preserved EF include:

  • Clinical features consistent with severe AS (typical symptoms, elderly patient >70 years) 1
  • Qualitative imaging showing LV hypertrophy and reduced LV longitudinal function 1
  • Quantitative findings including AVA ≤0.8 cm², mean gradient 30-40 mmHg, and low stroke volume index (<35 mL/m²) 1

Hemodynamic Consequences

• The hypertrophied heart in AS patients may have:

  • Reduced coronary blood flow per gram of muscle 1
  • Limited coronary vasodilator reserve, even without coronary artery disease 1
  • Increased sensitivity to ischemic injury 1
  • Subendocardial ischemia during exercise or tachycardia, contributing to diastolic dysfunction 1

• Forceful atrial contraction plays an important role in ventricular filling without increasing mean left atrial pressure; loss of atrial contraction (as in atrial fibrillation) often leads to clinical deterioration 1

Management Considerations

• Symptomatic patients with severe AS and preserved EF should be considered for intervention (AVR), particularly if AS is the most likely cause of symptoms 1
• In patients with low-flow, low-gradient AS with preserved EF, careful confirmation of severe AS is essential before proceeding with intervention 1
• Early AVR has been associated with significant improvement in long-term survival and functional status in patients with severe AS and low transvalvular gradient despite normal LVEF 3
• Patients with inappropriately decreased stroke volume relative to afterload (despite preserved EF) show lower contractility, higher heart rate, shorter ejection time, and elevated LV diastolic pressures, suggesting failed hemodynamic adaptation 4

Pitfalls and Caveats

• Paradoxical low-flow, low-gradient AS with preserved EF must be diagnosed with particular care, as other more frequent reasons for small valve area and low gradient with normal EF may include technical factors in AVA calculation 1
• In elderly patients, especially women, excessive or inappropriate LV hypertrophy may develop (wall thickness greater than necessary), which has been associated with high perioperative morbidity and mortality 1
• First phase ejection fraction (EF1) may be a more sensitive marker of early LV systolic dysfunction in AS patients with preserved total EF, as it can detect subendocardial dysfunction before total EF declines below 50% 5

In summary, aortic stenosis is the primary valvular pathology that leads to cardiac insufficiency with preserved ejection fraction through mechanisms of diastolic dysfunction, increased LV filling pressures, and impaired ventricular relaxation while maintaining systolic function.