Analysis Of The Relationship Between Plasma Carnitine Levels And Non-valvular Atrial Fibrillation

ObjectiveThe aim of this study is to analyze the changes of plasma carnitine level in patients with atrial fibrillation(AF)by metabolomics method,and to explore the correlation between plasma carnitine level and AF and its predictive value in AF.MethodsThis was a retrospective study.The clinical data of 195 consecutive patients with non-valvular atrial fibrillation and sinus rhythm hospitalized for other reasons in the second Hospital of Dalian medical university from January 2020 to January 2022 were collected.According to the2020ESC/EACTS guidelines for the diagnosis and management of Atrial fibrillation,AF was divided into paroxysmal AF and persistent AF.There were 90 patients with non-valvular AF(45 patients with paroxysmal AF and 45 patients with persistent AF),and 105 patients with sinus rhythm as control group.The general clinical data of the two groups of patients,including age,gender,blood pressure,body mass index(BMI),left atrial diameter(LAD),smoking history,alcohol drinking history,hypertension history,cerebral infarction history,coronary heart disease history and blood lipid,blood uric acid(BUA),plasma carnitine level were collected.Statistical analysis method: The measurement data conforming to normal distribution were expressed as(?X±S),and the two groups were compared by two independent sample t-test.Measurement data with skewed distribution were expressed as median M(P25,P75),and MannWhitney U test was used to compare the difference between the two groups.Count data were expressed as percentage,and chi-square test was used to compare the two groups.Binary logistic regression equation was used to analyze whether the above indicators were independent related factors for AF.Receiver operating characteristic curve was used to evaluate the diagnostic value of carnitine for AF.P < 0.05 was considered as statistical significance.ResultsBaseline data characteristics: there were no significant differences in gender,systolic blood pressure,diastolic blood pressure,smoking history,drinking history,hypertension history,LDL-C,TC,and TG between the AF group and the sinus rhythm group(P>0.05).However,age,history of coronary heart disease,history of cerebral infarction,BMI,BUA and LAD in the AF group were significantly higher than those in the sinus rhythm group(P<0.05),and HDL-C in the AF group was significantly lower than that in the sinus rhythm group(P=0.001).There were no significant differences in gender,age,smoking history,drinking history,coronary heart disease history,cerebral infarction history,hypertension history,systolic blood pressure,diastolic blood pressure,HDL-C,LDL-C,TC,TG,BMI,and BUA between the two groups(P>0.05).However,LAD was significantly higher in the persistent AF group than in the paroxysmal AF group(P < 0.001).The plasma level of partial carnitine was significantly higher in patients with atrial fibrillation than in patients with sinus rhythm.It was found that plasma levels of 9 kinds of carnitines in the AF group were significantly higher than those in the sinus rhythm group.And the difference was statistically significant(P<0.05).There was no significant difference in residual carnitine levels such as hydroxybutyl carnitine C4-OH between the two groups(P > 0.05).Further analysis of carnitine levels in the paroxysmal atrial fibrillation group and persistent atrial fibrillation group showed that the plasma levels of four carnitines in the persistent atrial fibrillation group were significantly higher than those in the paroxysmal atrial fibrillation group.And the difference was statistically significant(P<0.05).There was no significant difference in residual carnitine levels such as free carnitine CO between the two groups(P >0.05).Using binary logistic regression equation,with atrial fibrillation as the dependent variable,Nine kinds of carnitines,age,history of coronary heart disease,history of cerebral infarction,BMI,BUA,LAD,and HDL-C were used as self-contained variables,Multivariate analysis showed that age(P=0.026),HDL-C(P=0.029),LAD(P<0.001)and free carnitine CO(P=0.012)were independent relative factors for AF.ROC curve analysis of the value of free carnitine CO in the diagnosis of AF: the area under the curve of free carnitine CO predicting AF was0.780(95%CI 0.716-0.844,P<0.001),the sensitivity was 66.7%,and the specificity was 78.1% with 27.945 μmol/L as the cut-off point.ConclusionThe plasma levels of some carnitines in patients with atrial fibrillation were significantly higher than those in patients with sinus rhythm,including free carnitine CO,acetylcarnitine C2,propionylcarnitine C3,butyrylcarnitine C4,isovalerylcarnitine C5,hydroxyisovalerylcarnitine C5-OH,palmitoylcarnitine C16,octadecanoylcarnitine C18,and hexadecanoylcarnitine C26.The occurrence of atrial fibrillation may be related to the metabolic disorder of this part of carnitine.The levels of acetyl-carnitine C2,hydroxybutyrylcarnitine C4-OH,palmitoylcarnitine C16 and hydroxypalmitoylcarnitine C16:1-OH in patients with persistent AF were significantly higher than those in patients with paroxysmal AF.Free carnitine CO is an independent relating factor for AF,and its elevated level suggests that patients may be susceptible to AF.