Franz Wiesbauer and Mike Cadogan Goodbye “Massive” and “Submassive” The first-ever AHA/ACC clinical practice guideline on acute pulmonary embolism drops a new A-to-E severity classification. Here’s what emergency physicians need to know...
The first-ever AHA/ACC clinical practice guideline on acute pulmonary embolism drops a new A-to-E severity classification, promotes PERT teams to Class 1, and finally says it: DOACs over warfarin, LMWH over UFH. Here’s what emergency physicians need to know…
Creager MA et al. 2026 AHA/ACC/ACCP/ACEP/CHEST/SCAI/SHM/SIR/SVM/SVN Guideline for the Evaluation and Management of Acute Pulmonary Embolism in Adults: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines . Circulation. 2026 Mar 24;153(12):e977-e1051.
The 2011 AHA scientific statement on massive and submassive PE was widely used but it was not a clinical practice guideline. The 2019 ESC guidelines from Europe became the de facto standard for many clinicians. This 2026 document is the first dedicated AHA/ACC clinical practice guideline for acute PE in adults. It is a big deal.
A completely new severity classification. The old language of massive, submassive, and low-risk…is gone. In its place: AHA/ACC Acute PE Clinical Categories A through E , with subcategories.
There is also a respiratory modifier (R) that can be appended to any subcategory when hypoxia, tachypnea, or escalating oxygen requirements are present.
“Submassive” covered a huge range of patients from the one who is hypoxic and deteriorating, to the one who has a mildly elevated troponin and feels fine. The new system captures that difference. Category C1 (elevated severity score but normal RV and normal biomarkers) is very different from Category D2 (normotensive shock with end-organ dysfunction), and each one now has its own name and its own management path.
Category A or B → Think about sending them home. The guideline says outpatient treatment is reasonable for Category A and B patients using a decision tool (Hestia, PESI, or sPESI). This is a Class 2a recommendation backed by randomised trial data. The HOME-PE trial showed both Hestia and sPESI performed equally well for selecting safe-to-discharge patients.
Category C and above → Hospitalise, measure biomarkers, image the RV. At least one cardiac biomarker (troponin or BNP) should be measured. Lactate (venous or arterial) is now a Class 1 recommendation for Categories C-E. And RV imaging — preferably echocardiography over CT — is recommended for risk stratification.
Categories C-E → Activate PERT. The recommendation for PE response teams is now Class 1, Level B-NR. This is a notable upgrade.
In patients with acute PE who are eligible for oral anticoagulation, DOACs are recommended over vitamin K antagonists, unless contraindicated. (Class 1, Level B-R)
The reasoning : LMWH reduces recurrent VTE more effectively than UFH without increasing major bleeding. It has predictable dosing, does not require routine monitoring, and carries lower risk of heparin-induced thrombocytopenia. DOACs are preferred over warfarin for lower bleeding risk (especially intracranial haemorrhage), simpler dosing, and fewer drug-food interactions.
Obesity (BMI >30): DOACs are reasonable over warfarin — even in severe obesity. Meta-analyses show apixaban and rivaroxaban are at least as safe and effective as warfarin in this group.
Antiphospholipid syndrome: Warfarin wins here. DOACs are associated with higher arterial thrombotic events in thrombotic APS. The exception: single-antibody, low-risk APS without history of arterial thrombosis — a DOAC may be considered.
Pregnancy: LMWH or UFH only. DOACs and warfarin are classified as potentially harmful (Class 3: Harm).
Kidney disease (stage 2-3): DOAC over warfarin (Class 1, Level A). For stage 4-5 or dialysis, apixaban may be considered but the data are uncertain.
Liver disease: DOACs are reasonable for Child-Pugh A and B. For Child-Pugh C: avoid DOACs (Class 3: Harm).
The guideline introduces a structured approach based on the new categories. Here is the practical summary:
One important nuance: the PEERLESS trial (550 patients randomised to CDL vs MT) showed no significant difference in 30-day mortality or major bleeding between the two approaches. So if a catheter-based approach is selected, the choice between CDL and MT remains operator- and situation-dependent.