Effect Of Patent Foramen Ovale On Cerebral Infarction In Different Age Groups

Objective:To know the presence of patent foramen ovale(PFO) in patients with cerebral infarction of undetermined etiology and to explore the relationship between PFO and cerebral infarction, if there is difference of effect of PFO on cerebral infarction between different ages. To know etiology, risk factors and the proportion of subtypes based on TOAST classification of patients with cerebral infarction in different age groups.Methods:238young and middle-aged(<55years old) and373aged(≥55years old) patients with cerebral infarction were performed blood routine, blood fat, blood glucose, homocysteine, Hypersensitive c-reactive protein, anticardiolipin antibody, tumor maker, brain MRI, brain MRA, cervical vascular ultrasound, transcranial Doppler sonography, transthoracic echocardiography and other tests to look for the cause of leading to cerebral infarction and were divided to5subtypes based on TOAST classification.The patients which were not found a clear etiology by all tests were enrolled as cryptogenic stroke (CS) group and divided into2subgroups by age: young and middle-aged CS group(<55years old) and aged CS group(≥55years old). Non stroke patients of the same age were enrolled as control group of the2CS subgroups. Both CS group and control group were recorded clinical basic data and had bubble study to determine the presence of PFO or not. To compare frequency of PFO in CS group with that in control group and to analyze the relationship between PFO and cerebral infarction and if there is difference of effect of PFO on cerebral infarction between different ages. SPSS17.0statistical software package was used for processing data, and P<0.05was considered that difference was statistically significant. The data was analyzed using independent sample t test for continuous variables, chi-square test for categorical variables between two groups. Multivariate logistic regression analysis was used to test the association between PFO and CS.Results:In young and middle-aged patients with cerebral infarction, the proportion of every TOAST subtype in turn were stroke of undetermined etiology(SUE), large artery atherosclerosis(LAA), small artery occlusion(SAO), stroke of other determined etiology(SOE) and cardioembolism(CE). In aged patients with cerebral infarction, the proportions of every subtype in turn were LAA, SUE, SAO, CE and SOE. In94cases of young and middle-aged patients with CS, PFO was detected in21cases while in83cases of young and middle-aged control group, PFO was detected in6cases. The frequency of PFO in young and middle-aged CS patients was much higher than that in its control group and the difference was statistical significant (22.34%vs7.23%, P=0.005). In87cases of aged patients with CS, PFO was detected in16cases while in77cases of aged control group PFO was detected in5cases. The frequency of PFO in aged CS patients was higher than that in its control group and the difference was statistical significant (18.39%vs6.49%, P=0.023). After adjusting for age, gender, hypertension, triglyceride, HDL, LDL and fibrinogen, multivariate logistic regression analysis showed that the presence of PFO was an independent risk factor for CS both in young and middle-aged patients (OR=3.749,95%CI1.393～10.089, P=0.009) and in aged patients (OR=3.563,95%CI1.176～10.792,P=0.025).Chi-square test showed that there was not significant difference for the frequency of PFO between two subgroups of cerebral infarction of undetermined etiology (young and middle-aged CS group and aged CS group), and it had no statistical significance. But as the possible etiology of leading to cerebral infarction, effect of PFO on cerebral infarction in young and middle-aged patients was more than that in aged patients, and the difference was statistical significant (P=0.022).Conclusion:The presence of PFO was an independent risk factor for CS both in young and middle-aged patients and in aged patients. The frequency of PFO between in young and middle-aged patients with cryptogenic cerebral infarction and in aged patients with cryptogenic cerebral infarction had no statistical significance, and it showed that age was not a main factor affecting the association between PFO and cryptogenic cerebral infarction. Effect of PFO on cerebral infarction in young and middle-aged patients was more than that in aged patients.