Differential right ventricular regional function and the effect of pulmonary hypertension: three-dimensional echo...

Area of Science:

• Cardiology
• Cardiac Physiology
• Echocardiography

Background:

• The right ventricle (RV) exhibits a multicompartmental structure.
• Understanding the differential function of RV compartments is crucial for assessing overall cardiac health.

Purpose of the Study:

• To evaluate the distinct functions of the right ventricular (RV) inflow, apical, and outflow compartments.
• To investigate the interrelationships between these compartments and their response to pulmonary arterial hypertension (PAH).

Main Methods:

• Utilized 2D and 3D echocardiography with Doppler techniques in 45 subjects (16 controls, 29 with left-sided heart failure).
• Patients were stratified into groups based on the presence (group 2) or absence (group 1) of secondary PAH.

Main Results:

• Strong correlations were found between RV dimensions and volumes (2D/3D) and between tricuspid annular plane systolic excursion and RV ejection fraction.
• Apical ejection fraction was consistently lower than inflow and outflow fractions across all groups.
• Patients with PAH showed reduced ejection fractions and prolonged isovolumic contraction/relaxation times, indicating impaired RV function.

Conclusions:

• The right ventricle (RV) comprises distinct functional compartments (inflow, apical, outflow) with varying contributions to systolic function.
• Pulmonary arterial hypertension (PAH) transforms the RV into a dyssynchronous single compartment, potentially exacerbating cardiac dysfunction.