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............................................................................................. limitation, or CTEPH at long-term follow-up. A small randomized trial of 83 patients suggested that thrombolysis might improve functional capacity at 3 months compared with anticoagulation alone.278

In the PEITHO trial,179 mild persisting symptoms, mainly dyspnoea, were present in 33% of the patients at long-term (at 41.6 ± 15.7 months) clinical follow-up.288 However, the majority of patients (85% in the tenecteplase arm and 96% in the placebo arm) had a low or intermediate probability—based on the ESC Guidelines definition289—of persisting or new-onset PH at echocardiographic followup.288 Consequently, the findings of this study do not support a role for thrombolysis with the aim of preventing long-term sequelae (section 10) after intermediate-risk PE, although they are limited by the fact that clinical follow-up was available for only 62% of the study population.

6.3.2 Percutaneous catheter-directed treatment Mechanical reperfusion is based on the insertion of a catheter into the pulmonary arteries via the femoral route. Different types of catheters (summarized in Supplementary Data Table 11) are used for mechanical fragmentation, thrombus aspiration, or more commonly a pharmacomechanical approach combining mechanical or ultrasound fragmentation of the thrombus with in situ reduced-dose thrombolysis. Most knowledge about catheter-based embolectomy is derived from registries and pooled results from case series.290,291 The overall procedural success rates (defined as haemodynamic stabilization, correction of hypoxia, and survival to hospital discharge) of percutaneous catheter-based therapies reported in these studies have reached 87%;292 however, these results may be subject to publication bias. One RCT compared conventional heparin-based treatment and a catheter-based therapy combining ultrasoundbased clot fragmentation with low-dose in situ thrombolysis in 59 patients with intermediate-risk PE. In that study, ultrasoundassisted thrombolysis was associated with a larger decrease in the RV/LV diameter ratio at 24 h, without an increased risk of bleeding.293 Data from two prospective cohort studies294,295 and a registry,296 with a total of 352 patients, support the improvement in RV function, lung perfusion, and PAP in patients with intermediate- or high-risk PE using this technique. Intracranial haemorrhage was rare, although the rate of Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) severe and moderate bleeding complications was 10% in one of these cohorts.294 These results should be interpreted with caution, considering the relatively small numbers of patients treated, the lack of studies directly comparing catheterdirected with systemic thrombolytic therapy, and the lack of data from RCTs on clinical efficacy outcomes.

6.3.3 Surgical embolectomy Surgical embolectomy in acute PE is usually carried out with cardiopulmonary bypass, without aortic cross-clamping and cardioplegic cardiac arrest, followed by incision of the two main pulmonary arteries with the removal or suction of fresh clots. Recent reports have indicated favourable surgical results in highrisk PE, with or without cardiac arrest, and in selected cases of intermediate-risk PE.297300 Among 174 322 patients hospitalized between 1999 and 2013 with a diagnosis of PE in New York state, survival and recurrence rates were compared between patients who underwent thrombolysis (n = 1854) or surgical embolectomy (n = 257) as first-line therapy.297 Overall, there

Table 10 Thrombolytic regimens, doses, and contraindications

Molecule Regimen Contraindications to fibrinolysis rtPA 100 mg over 2 h Absolute

History of haemorrhagic stroke or stroke of unknown origin Ischaemic stroke in previous 6 months Central nervous system neoplasm Major trauma, surgery, or head injury in previous 3 weeks Bleeding diathesis Active bleeding Relative Transient ischaemic attack in previous 6 months Oral anticoagulation Pregnancy or first post-partum week Non-compressible puncture sites Traumatic resuscitation Refractory hypertension (systolic BP >180 mmHg) Advanced liver disease Infective endocarditis Active peptic ulcer

0.6 mg/kg over 15 min (maximum dose 50 mg)a

Streptokinase 250 000 IU as a loading dose over 30 min, followed by 100 000 IU/h over 1224 h

Accelerated regimen: 1.5 million IU over 2 h

Urokinase 4400 IU/kg as a loading dose over 10 min, followed by

4400 IU/kg/h over 1224 h Accelerated regimen: 3 million IU over 2 h

BP = blood pressure; IU = international units; rtPA, recombinant tissue-type plasminogen activator. aThis is the accelerated regimen for rtPA in pulmonary embolism; it is not officially approved, but it is sometimes used in extreme haemodynamic instability such as cardiac arrest. Downloaded from academic.oup.com/eurheartj/article/41/4/543/5556136 by guest on 07 October 2026