Association between left ventricular diastolic function and right ventricular function and morphology in asymptomatic...

Area of Science:

• Cardiology
• Cardiovascular Physiology

Background:

• Aortic stenosis (AS) commonly causes left ventricular (LV) diastolic dysfunction.
• The impact of diastolic dysfunction on right ventricular (RV) function and loading in asymptomatic AS patients remains unclear.

Purpose of the Study:

• To investigate the association between LV diastolic dysfunction and RV loading conditions and function in asymptomatic AS patients.

Main Methods:

• 41 asymptomatic AS patients underwent right heart catheterization and echocardiography at rest and during maximal exercise.
• Cardiac magnetic resonance imaging (cMRI) assessed chamber size and morphology.
• Calculated parameters included RV stroke work index, pulmonary artery (PA) compliance and elastance, and right atrial pressure (RAP).

Main Results:

• Patients with diastolic dysfunction had smaller RV end-diastolic and end-systolic volumes compared to those with normal LV filling.
• Increased mean RAP during exercise was observed in patients with moderate to severe diastolic dysfunction (63% vs. 0%).
• Grade 2 diastolic dysfunction showed increased PA pressure and elastance, correlating inversely with maximal oxygen consumption.

Conclusions:

• Moderate diastolic dysfunction in AS is linked to elevated RV afterload (elastance).
• This RV afterload is compensated at rest but leads to increased RAP during exercise.
• Diastolic dysfunction is inversely related to exercise capacity in AS patients.