The role of Pulmonary Artery Pulsatility Index to assess the outcomes following catheter directed therapy in patients with intermediate-to-high and high-risk pulmonary embolism

Abstract

Background

The clinical impact of catheter-directed therapy (CDT) for pulmonary embolism (PE) on right ventricular function and procedural outcomes remains undefined.

Methods

This observational retrospective study included consecutive patients who underwent CDT for PE at San Giovanni Bosco Hospital, Italy, and First Department of Cardiology, Poznan University Clinical Hospital, Poland, between 2021 and 2023. Clinical characteristics, PE risk stratification, pre and post-interventional invasive pulmonary artery pressure (PAP), and Pulmonary Artery Pulsatility Index (PAPi) were collected. The primary endpoint was in-hospital death.

Results

Among 165 patients (53 % male, mean age 63 ± 5.6 years), 65.6 % had multiple PE risk factors. 32.7 % were classified as high-risk (HR) PE, and 67.3 % as intermediate-high risk (IHR). Treatments included transcatheter thrombolysis (17 %), FlowTriever device (10 %), and Indigo Cath8 or Lightning 12 device (73 %), with 7 % requiring ECMO support. In IHR patients, mean PAP significantly decreased from 31.7 ± 7.1 to 23.4 ± 6.1 mmHg (p < 0.01) and PAPi from 3.1 ± 0.1 to 2.9 ± 0.1 (p < 0.01). HR patients had no significant changes in PAP or PAPi overall, but those who survived without events showed significant reductions in PAP (29.1 ± 8.7 to 23.8 ± 5.5, p < 0.02) and increases in PAPi (1.5 ± 0.6 to 2.0 ± 0.5, p < 0.01). In the HR group, a delta PAPi >0.45 predicted positive outcomes with 65.7 % sensitivity and 75 % specificity (AUC 0.83).

Conclusion

CDT for PE significantly impacts PAP and PAPi in acute PE patients. Normalization of PAPi in IHR patients and its increase in HR patients may indicate procedural success and right ventricular recovery. Hemodynamic changes could serve as important markers for procedural efficacy and outcome assessment in these groups.