Mean platelet volume, an indicator of platelet reactivity, is increased in patients with patent foramen ovale

Clinical and infarction patterns of PFO-related cryptogenic strokes and a prediction model

Objectives

The higher than expected PFO rate in CS patients has raised concerns that paradoxical embolism maybe the pathophysiologic mechanism for strokes. However, only a small proportion of pathogenic PFOs cause CS. Therefore, accurate recognition of patients with pathogenic PFOs among all CS patients could guide clinical decision making in selecting the most appropriate treatment. The aim of this study was to devise a new algorithm to stratify cryptogenic stroke (CS) patients into pathogenic patent foramen ovale (p‐PFO)‐ and non‐p‐PFO‐related patients.

Methods

A total of 1201 patients with acute ischemic stroke were recruited from two different medical centers, and 253 CS patients were identified. Of the 253 patients, 111 were diagnosed with PFO using contrast transcranial Doppler. Data on medical histories, neuroimaging and laboratory tests were compared in CS patients with or without PFO.

Results

Compared with PFO‐negative CS patients, PFO‐positive CS patients showed younger onset age, lower incidence of hypertension and dyslipidemia, characteristic infarction pattern in magnetic resonance imaging and specifically altered platelet activity and coagulation function. Based on the above information, we constructed a PFO judgment formula (Hr‐PFOJ) by means of feature weight estimation and predictive performance evaluation to predict pathogenic PFO in CS patients with a sensitivity of 76.3% and a specificity of 66.5%.

Interpretations

Hr‐PFOJ judgment formula is a useful screening tool for identification of patients with pathogenic PFO who may benefit from PFO‐related treatment.

Association between the rs342293 polymorphism and adverse cardiac events in patients undergoing percutaneous coronary intervention

The single nucleotide polymorphism (SNP) rs342293 has been shown to influence platelet number and mean platelet volume (MPV). We investigated the association between the rs342293 polymorphism and cardiovascular outcome in a prospective cohort study. The rs342293 polymorphism was analysed in 404 patients with coronary artery disease undergoing percutaneous coronary intervention. The rates of cardiac adverse events were recorded during two years of follow-up. The polymorphism was associated with MPV (median 10.1 fL, interquartile range [IQR]: 9.6 to 10.6 in patients with the CC-allele vs 10.4 fL, IQR: 9.9 to 11.1 in G>C SNP carriers; p<0.001), but not with platelet count. Survival analysis indicated that carriers of the rs342293 G variant had a substantially higher risk to develop cardiac adverse events compared with wild type carriers during two years of follow-up (33% vs 22%; adjusted hazard ratio = 1.63, 95% confidence interval = 1.06–2.52, p=0.027). The rs342293 SNP could explain 2.9% of the variability in MPV (p=0.01). In conclusion, patients undergoing coronary stenting who carry the G-variant of the rs342293 SNP which is associated with larger MPV are at higher risk for adverse cardiovascular outcome.