American Society of Hirudotherapy

Clinical outcomes and a high prevalence of abnormalities on comprehensive arterial and venous thrombophilia screening in TIA or ischaemic stroke patients with a patent foramen ovale, an inter-atrial septal aneurysm or both

Research article published in Journal of the neurological sciences (2017)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsAntimicrobial ResistanceLim ST et al. · Journal of the neurological sciences, 2017

Abstract

INTRODUCTION: Data are limited on the optimal management of cryptogenic TIA/stroke patients with a patent foramen ovale (PFO)±inter-atrial septal aneurysm (IASA), especially with an inherited thrombophilia. METHODS: Prospectively-collected data on TIA/ischaemic stroke patients with PFO, IASA or both who received 'goal-directed secondary-prevention medical treatment' were analysed. All patients had trans-oesophageal echocardiography, anti-nuclear, anti-cardiolipin, anti-beta 2 glycoprotein I antibodies, rheumatoid factor, lupus anticoagulant, protein C&S, anti-thrombin, factor VIII activity, activated protein C resistance, Factor V Leiden, prothrombin gene and MTHFR-c.677C>T mutation screening. ENA and homocysteine were assessed in the latter study period. RESULTS: Eighty-three patients were recruited. Mean follow-up: 48.1months. Forty-seven patients (56.6%) had an isolated PFO, 32 (38.6%) a PFO and an IASA, and 4 (4.8%) an IASA alone. Eighteen (21.7%) had ≥1 abnormality on thrombophilia screening. The most important abnormalities which lead to treatment changes in 11 patients (13.3%) were primary anti-phospholipid syndrome (N=3; 3.6%), protein S deficiency (N=2; 2.4%) hyper-homocysteinaemia (N=6/72 screened, 8.3%). Four patients (4.8%) opted for PFO closure: two with protein S deficiency, and two with no identified thrombophilia. Seven (8.4%) had recurrent TIA/ischaemic stroke during follow-up (overall annualised incidence: 2.1%), of whom five had a PFO alone and two a PFO and IASA. DISCUSSION: Comprehensive arterial and venous thrombophilia screening is warranted in TIA/ischaemic stroke patients with a PFO±IASA, is conclusively abnormal in over a fifth, and informed important decision-making regarding individualised therapy in 13.3% of patients. The incidence of recurrent vascular events in this population is low on optimal, personalised secondary-prevention treatment, even with an underlying thrombophilia.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAdultAgedEchocardiographyFemaleFibrinolytic AgentsForamen Ovale, PatentHeart Septal Defects, VentricularHumansIschemic Attack, TransientLongitudinal StudiesMaleMiddle Aged

Summary

Data are limited on the optimal management of cryptogenic TIA/stroke patients with a patent foramen ovale (PFO)±inter-atrial septal aneurysm (IASA), especially with an inherited thrombophilia. Prospectively-collected data on TIA/ischaemic stroke patients with PFO, IASA or both who received 'goal-directed secondary-prevention medical treatment' were analysed.

Why This Matters for Hirudotherapy

This prospective study examined 83 TIA/ischaemic stroke patients with a patent foramen ovale (PFO)±inter-atrial septal aneurysm (IASA) who underwent comprehensive arterial and venous thrombophilia screening while receiving goal-directed secondary-prevention treatment (mean follow-up 48.1 months). For ASH, the work is relevant because thrombophilia screening identifies patients who may require intensified anticoagulation — the therapeutic domain where leech-derived hirudin and its analogs (lepirudin, desirudin, bivalirudin) serve as direct thrombin inhibitors — and 21.7% of these patients had ≥1 clotting abnormality, with 13.3% having findings that directly altered management. The overall annualised recurrence rate of stroke/TIA was 2.1% on personalised treatment. An honest caveat: this was an observational study without a comparator group, so it cannot prove that screening improved outcomes, and it provides no data on any specific anticoagulant, including hirudin-class agents.

Citation

Clinical outcomes and a high prevalence of abnormalities on comprehensive arterial and venous thrombophilia screening in TIA or ischaemic stroke patients with a patent foramen ovale, an inter-atrial septal aneurysm or both.

Lim ST et al. · Journal of the neurological sciences, 2017

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