Pathophysiology of Fluid Retention and Heart Failure in Aortic Stenosis

Primary Hemodynamic Mechanism

Aortic stenosis causes fluid retention and congestive heart failure through progressive left ventricular pressure overload leading to concentric hypertrophy, diastolic dysfunction, elevated filling pressures, and ultimately backward transmission of pressure to the pulmonary circulation and systemic venous system, according to the American College of Cardiology 1
The obstruction at the aortic valve creates a chronic pressure overload on the left ventricle that develops gradually over years, as stated by the American College of Cardiology 1
Concentric left ventricular hypertrophy develops as the primary adaptive response, with the ventricle thickening to normalize wall stress according to Laplace's law, as reported by the American College of Cardiology 1
Diastolic dysfunction emerges as the hypertrophied, stiffened ventricle becomes less compliant, impairing ventricular filling and elevating left ventricular end-diastolic pressure, according to the American College of Cardiology 1
Reduced coronary reserve occurs due to increased myocardial oxygen demand from hypertrophy combined with compression of intramyocardial vessels, leading to subendocardial ischemia even without epicardial coronary disease, as stated by the American College of Cardiology 1

Depressed contractility eventually develops when the ventricle can no longer maintain adequate systolic function against the increased afterload, according to the American College of Cardiology 1

Sodium and water retention occurs through renal hypoperfusion and neurohormonal activation, leading to volume expansion and peripheral edema, as reported by the European Society of Cardiology, based on information from the European Journal of Heart Failure 2

Dyspnea results from pulmonary venous congestion and elevated pulmonary capillary pressures, according to the American College of Cardiology 1
Peripheral edema develops from systemic venous congestion and sodium/water retention, as reported by the European Society of Cardiology, based on information from the European Journal of Heart Failure 2

Survival after symptom onset averages only 2 years with heart failure, 3 years with syncope, and 5 years with angina in medically managed patients, according to the American College of Cardiology 1

Left ventricular ejection fraction may remain preserved until late in the disease course due to compensatory hypertrophy, masking significant diastolic dysfunction, as stated by the American College of Cardiology 1
Rapid decompensation can occur with triggers such as atrial fibrillation, anemia, or infection, however this fact is from Praxis Medical Insights and will be replaced if a similar fact from another source is found, currently it is reported by Praxis Medical Insights 3