452. Risk stratification in Acute Pulmonary Embolism with Dr. Stavros Konstantinides

CardioNerds (Dr. Billy-Joe Mullinax, Dr. Dinu Balanescu, and Dr. Jane Ehret) discuss risk stratification in acute pulmonary embolism with Dr. Stavros Konstantinides, Chair of the 2019 ESC Pulmonary Embolism Guidelines. Using a real-world case, this episode explores how modern PE care has moved beyond “massive” and “submassive” labels toward a dynamic, physiology-based approach. The discussion highlights the limitations of static risk scores, the importance of right ventricular dysfunction and biomarkers, and why normotension does not imply stability. Special emphasis is placed on intermediate-high risk PE, early identification of impending hemodynamic collapse, and the role of lactate, serial reassessment, and PERT teams in guiding escalation of care. Audio editing by CardioNerds intern, Joshua Khorsandi.The 2026 American multi-society PE guidelines were published after this episode was recorded.

Dr. Dinu Balanescu and Dr. Billy-Joe Mullinax are Co-chairs for the CardioNerds PE Series, developed in collaboration with the PERT Consortium.

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Pearls

Stable blood pressure does not mean low risk in PEHypotension is a late finding. Patients may have severe RV failure, hypoxia, and tissue hypoperfusion while remaining normotensive — a key concept behind “normotensive shock.”

Risk stratification in PE must be dynamic, not staticLegacy scores like PESI and Bova provide a snapshot and predict 30-day mortality, but they do not capture short-term trajectory or impending hemodynamic collapse.

Intermediate-high risk PE is a dangerous and heterogeneous groupPatients with RV dysfunction, positive biomarkers, tachycardia, hypoxemia, and elevated lactate may have in-hospital mortality approaching 15%, rivaling STEMI.

Lactate is a critical but underutilized marker in PEElevated lactate reflects tissue hypoxia and early circulatory failure and may identify patients at risk for collapse before blood pressure declines.

PERT enables physiology-driven, patient-centered PE carePERT teams operationalize continuous reassessment, integrate imaging, labs, and clinical trajectory, and allow timely escalation — shifting PE management from rigid categories to real-time decision-making.

Notes

Drafted by Dr. Jane Ehret.

1. What is the contemporary framework for risk stratification in acute pulmonary embolism?

Modern PE risk stratification prioritizes hemodynamics and right ventricular (RV) function rather than clot burden.

The 2019 ESC Guidelines classify PE into high risk, intermediate risk (low vs high), and low risk, based on: Hemodynamic status, RV dysfunction on imaging, and Cardiac biomarkers.

This framework emphasizes early mortality risk but requires clinical context to guide escalation decisions.

2. Why is normotension insufficient to define “stability” in PE?

Blood pressure is a late marker of circulatory failure in PE.

Patients can maintain normal BP through Tachycardia, Increased sympathetic tone, and RV compensation.

Many patients with preserved BP may already have shock physiology, including hypoxemia, elevated lactate, and RV failure — sometimes referred to as “normotensive shock.”

3. How should intermediate-risk PE be conceptualized clinically?

Intermediate-risk PE is heterogeneous, ranging from patients who do well on anticoagulation to those who deteriorate rapidly.

Intermediate-high risk PE is defined by RV dysfunction on imaging and positive cardiac biomarkers.

Clinical features such as tachycardia, increasing oxygen requirement, and elevated lactate identify patients at highest risk within this group.

4. What are the strengths and limitations of commonly used PE risk scores?

Legacy