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............................................................................................................................................................................. 7.1.2 Suspected pulmonary embolism without haemodynamic instability 7.1.2.1 Strategy based on computed tomographic pulmonary angiography The proposed strategy based on CTPA is shown in Figure 5. In patients admitted to the emergency department, measurement of plasma Ddimer is the logical first step following the assessment of clinical probability and allows PE to be ruled out in 30% of outpatients. D-dimer should not be measured in patients with a high clinical probability of PE, owing to a low negative predictive value in this population.323 It is also less useful in hospitalized patients because the number that needs to be tested to obtain a clinically relevant negative result is high.

In most centres, multidetector CTPA is the second-line test in patients with an elevated D-dimer level and the first-line test in patients with a high clinical probability of PE. CTPA is considered to be diagnostic of PE when it shows a clot at least at the segmental level of the pulmonary arterial tree. False-negative results of CTPA have been reported in patients with a high clinical probability of PE;115 however, such discrepancies are infrequent and the 3 month thromboembolic risk was low in these patients.171 Accordingly, both the necessity of performing further tests and the nature of these tests remain controversial in these clinical situations.

7.1.2.2 Strategy based on ventilation/perfusion scintigraphy In hospitals in which V/Q scintigraphy is readily available, it is a valid option for patients with an elevated D-dimer and a contraindication to CTPA. Also, V/Q scintigraphy may be preferred over CTPA to avoid unnecessary radiation, particularly in younger patients and in female patients in whom thoracic CT might raise the lifetime risk of breast cancer.324 V/Q lung scintigraphy is diagnostic (with either normal- or high-probability findings) in 3050% of emergency ward patients with suspected PE.75,122,134,325 The proportion of diagnostic V/Q scans is higher in patients with a normal chest X-ray, and this might support the use of a V/Q scan as a first-line imaging test for PE in younger patients, depending on local availability.326 The number of patients with inconclusive findings may further be reduced by taking into account clinical probability. Thus, patients with a non-diagnostic lung scan and low clinical probability of PE have a low prevalence of confirmed PE,124,325 and the negative predictive value of this combination is further increased by the absence of a DVT on lower-limb CUS. If a highprobability lung scan is obtained from a patient with low clinical probability of PE, confirmation by other tests should be considered.

7.2 Treatment strategies

7.2.1 Emergency treatment of high-risk pulmonary embolism The algorithm for a risk-adjusted therapeutic approach to acute PE is shown in Figure 6; an emergency management algorithm specifically for patients with suspected acute high-risk PE is proposed in Supplementary Data Figure 1. Primary reperfusion treatment, in most cases systemic thrombolysis, is the treatment of choice for patients with high-risk PE. Surgical pulmonary embolectomy or percutaneous catheter-directed treatment are alternative reperfusion options in patients with contraindications to thrombolysis, if expertise with either of these methods and the appropriate resources are available on-site. Following reperfusion treatment and haemodynamic stabilization, patients recovering from high-risk PE can be switched from parenteral to oral anticoagulation. As patients belonging to this risk category were excluded from the phase III NOAC trials, the optimal time point for this transition has not been determined by existing evidence but should instead be based on clinical judgement. The specifications concerning the higher initial dose of apixaban or rivaroxaban (for 1 and 3 weeks after PE diagnosis, respectively), or the minimum overall period (5 days) of heparin anticoagulation before switching to dabigatran or edoxaban, must be followed (see Supplementary Data Table 8 for tested and approved regimens).

7.2.2 Treatment of intermediate-risk pulmonary embolism For most cases of acute PE without haemodynamic compromise, parenteral or oral anticoagulation (without reperfusion techniques) is adequate treatment. As shown in Figure 6, normotensive patients with at least one indicator of elevated PE-related risk, or with aggravating conditions or comorbidity, should be hospitalized. In this group, patients with signs of RV dysfunction on echocardiography or CTPA (graphically presented in Figure 3), accompanied by a positive troponin test, should be monitored over the first hours or days due to the risk of early haemodynamic decompensation and circulatory collapse.179 Routine primary reperfusion treatment, notably full-dose systemic thrombolysis, is not recommended, as the risk of potentially life-threatening bleeding complications appears too high for the expected benefits from this treatment.179 Rescue thrombolytic therapy or, alternatively, surgical embolectomy or percutaneous catheter-directed treatment should be reserved for patients who develop signs of haemodynamic instability. In the PEITHO trial, the mean time between randomization and death or haemodynamic decompensation was 1.79 ± 1.60 days in the placebo (heparin-only) arm.179 Therefore, it appears reasonable to leave patients with intermediate-high-risk PE on LMWH anticoagulation over the first 2 - 3 days and ensure that they remain stable before switching to oral anticoagulation. As mentioned in the previous section, the specifications concerning the increased initial dose of apixaban or rivaroxaban, or the minimum overall period of heparin anticoagulation before switching to dabigatran or edoxaban, must be followed. Suggestions for the anticoagulation and overall management of acute PE in specific clinical situations, for which conclusive evidence is lacking, are presented in Supplementary Data Table 9.

7.2.3 Management of low-risk pulmonary embolism: triage for early discharge and home treatment As a general rule, early discharge of a patient with acute PE and continuation of anticoagulant treatment at home should be considered if three sets of criteria are fulfilled: (i) the risk of early PE-related death or serious complications is low (section 5); (ii) there is no serious comorbidity or aggravating condition(s) (see section 5) that would mandate hospitalization; and (iii) proper outpatient care and anticoagulant treatment can be provided, considering the patient’s (anticipated) compliance, and the possibilities offered by the healthcare system and social infrastructure. Randomized trials and prospective management cohort studies that investigated the feasibility and safety of early discharge, and home treatment, of PE adhered to these principles, even though Downloaded from academic.oup.com/eurheartj/article/41/4/543/5556136 by guest on 07 October 2026