Mitral Effective Regurgitant Orifice Area Predicts Pulmonary Artery Pressure Level in Patients with Aortic Valve...

Area of Science:

• Cardiology
• Echocardiography
• Pulmonary Hypertension

Background:

• Mitral regurgitation (MR) and pulmonary hypertension (PH) are common in aortic valve stenosis (AS).
• The role of quantified MR in causing PH across AS severity is not fully understood.
• This study investigates the link between quantified MR and PH in AS patients.

Purpose of the Study:

• To determine if quantitative MR measurements are associated with PH in patients with AS.
• To explore the independent contribution of MR quantification to PH.
• To compare the association of MR quantification with PH to other diastolic dysfunction markers.

Main Methods:

• Prospective enrollment of 642 patients with AS (peak aortic velocity ≥ 2.5 m/sec).
• Echocardiography used to measure effective regurgitant orifice area (ERO) and regurgitant volume via proximal isovelocity surface area.
• Systolic pulmonary artery pressure calculated using tricuspid regurgitation pressure gradient and right atrial pressure.

Main Results:

• MR was present in 29% of patients; 82% had ERO < 0.20 cm².
• ERO and regurgitant volume showed significant associations with systolic pulmonary artery pressure (R²=0.30 and R²=0.35, P<.0001).
• This association persisted after multivariate adjustment and in subgroups with severe AS or reduced ejection fraction (OR for PH: 3.56 per 0.10 cm² ERO increase).

Conclusions:

• Effective regurgitant orifice area (ERO) is independently associated with pulmonary hypertension (PH) in patients with mitral regurgitation (MR) and aortic valve stenosis (AS).
• MR quantification, particularly ERO, appears to be a stronger predictor of PH than other markers of left ventricular diastolic dysfunction.
• These findings emphasize the importance of quantifying MR in the management of AS patients with or at risk for PH.