EROSION signals anti-thrombotic therapy without stenting for ACS patients
medwireNews: Conservative anti-thrombotic therapy with stenting may be an effective treatment option for a quarter of patients with acute coronary syndrome (ACS), research suggests.
The proof-of-concept study – EROSION – found that among 405 ACS patients, plaque erosion, identified using optical coherence tomography, was the underlying cause in 25.4%.
And among 60 of these patients with plaque erosion and residual diameter stenosis below 70% who received anti-thrombotic therapy without stenting, thrombus volume was successfully reduced by more than 50% over a 1-month period in 78%, with 37% having no visible thrombus at this time.
“Our strategy of conservative anti-thrombotic therapy without stenting in selected ACS patients caused by plaque erosion represents a potential new treatment paradigm”, say Ik-Kyung Jang (Massachusetts General Hospital, Boston, USA).
The patients, 96.7% of whom had ST-segment elevation myocardial infarction, were treated with aspirin, ticagrelor and unfractionated heparin prior to catheterisation. Thrombectomy and glycoprotein IIb/IIIa inhibitors, at the discretion of the treating cardiologist, were used in 85.0% and 63.3% of patients, respectively. For 3 days post-catheterisation, the patients were treated with unfractionated heparin or low molecular weight heparin and all of the patients were treated with dual antiplatelet therapy (aspirin and ticagrelor) and statins at discharge.
Over the 1-month follow-up, thrombus volume decreased significantly by 94.2%, from an average 3.7 mm3 to 0.2 mm3, with other thrombus measures including thrombus burden, thrombus area, thrombus length and thrombus score also decreasing significantly from baseline. And the likelihood of 100% volume reduction was greater among patients treated with glycoprotein inhibitors.
The minimal flow area of the culprit lesion increased significantly, from 1.7 mm2 to 2.1 mm2, likely as a result of thrombus dissolution, says the team.
Although the small number of patients made the trial not sufficiently powered to make firm conclusions on the effect of the treatment strategy in preventing major adverse cardiovascular events, the researchers note that all but two patients remained asymptomatic.
One patient died of gastrointestinal bleeding while the second required repeated percutaneous coronary intervention.
The researchers comment in the European Heart Journal that distinct pathological features associated with plaque erosion, compared with thrombus rupture – the most common cause of ACS – may explain the positive findings.
The preserved vascular integrity, less severe stenosis of the coronary lumen and platelet-rich, rather than fibrin-rich, thrombus associated with plaque erosion may make effective anti-thrombotic therapy without stenting “sufficient to restore coronary artery patency and allow healing of the endothelial layer”, they explain.
By Lucy Piper
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