Background: Pulmonary hypertension (PH) is common in patients with left-side valvular diseases, especially with mitral regurgitation (MR). Measurement using pulmonal artery catheter (PAC) is the gold standard to asses pulmonary vascular pressures. During mitral valve surgery echocardiography is routinely used for valvular management and to evaluate pulmonary hemodynamic. The accuracy of echocardiographic measurements is controversial in the literature. We aimed to evaluate the reliability and accuracy of the noninvasive measurement for systolic pulmonary artery pressure (SPAP) using Doppler echocardiography compared to the invasive measurement using PAC in patients presenting with MR undergoing surgery.

Methods: This prospective observational study evaluated 146 patients with MR undergoing cardiac surgery between 09/2020 and 10/2021. All patients underwent simultaneous SPAP assessment by PAC and transesophageal echocardiography at three different time points: before heart-lung-machine (HLM), after weaning from HLM and at the end of surgery.

Results: Mean patients’ age was 61 ± 11.5 years, and 51 (35%) patients were female. Most of patients presented with severe MR (n = 126; 86.3%) or endocarditis (n = 18; 12.3%). Patients underwent either isolated mitral valve surgery (n = 65; 44.5%) or mitral valve surgery combined with other surgeries (n = 81; 55.5%). Mean SPAP was underestimated by transesophageal echocardiographic measurement in comparison to PAC measurement before HLM (41.9 ± 13.1 mmHg vs. 44.8 ± 13.8 mmHg, p < 0.001), after weaning from HLM (37.6 ± 9.3 mmHg vs. 42.4 ± 10.1 mmHg, p < 0.001), and at the end of surgery (35.6 ± 9.1 mmHg vs. 39.9 ± 9.9 mmHg, p < 0.001). This difference remained within the sub-analysis in patients presented with moderate or severe PH during all the time points. Bland-Altman analysis showed that transesophageal echocardiographic measurement underestimate SPAP in comparison to PAC as these two approaches are significantly different from one another.

Conclusions: In patients presented with MR, transesophageal Doppler echocardiography could asses the presence of PH with high probability. This assessment is however underestimated and the use of PAC in those patients to diagnose, classify and monitor the therapy of PH remains recommended if required.