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Fundamento: O exercício intenso e continuado em atletas provoca fenótipos de remodelamento adaptativo, cujos parâmetros podem ser avaliados pela ecocardiografia convencional, e de deformação miocárdica. Assim, foi comparado o remodelamento miocárdico em atletas do sexo feminino (grupo atletas) com mulheres sedentárias da mesma faixa etária (grupo-controle) e entre atletas com maior e menor tempo de treinamento. Métodos: Foram selecionadas 57 futebolistas femininas (grupo atletas) e 25 mulheres sadias sedentárias (grupocontrole). As atletas foram divididas em dois grupos: grupo principal, com 32 atletas, e grupo sub-17, com 25 atletas. Foram determinadas, através de ecocardiografia, as dimensões, a função sistólica e diastólica das câmaras cardíacas e a deformação miocárdica (strain longitudinal, circunferencial, radial e mecânica rotacional), utilizando a estatística Z com significância de p < 0,05. Resultados: A idade dos grupos atletas, controle, principal e sub-17 foi de 22,1±6,3; 21,2±5,0; 26,5±5,1; e 16,5±0,6, respectivamente. O peso, o índice de massa corporal e a frequência cardíaca foram menores no grupo atletas. A espessura das paredes, o índice de massa do ventrículo esquerdo (VE), o volume do átrio esquerdo (AE), a fração de ejeção e as dimensões do ventrículo direito (VD) foram maiores no grupo atletas, mas dentro de valores normais. A deformação miocárdica mostrou diminuição do strain radial, da rotação basal, da rotação apical e do twist, sugerindo mecanismo de reserva contrátil. Esses parâmetros foram menores no grupo principal, que também apresentava maior espessura das paredes, maior volume do AE e maior tamanho do VD, sugerindo que o aumento da reserva contrátil se relaciona com maior tempo de treinamento. Conclusões: As atletas do sexo feminino com treinamento intenso de longa duração apresentam remodelamento adaptativo das câmaras cardíacas e aumento da reserva contrátil observada em repouso, com esses parâmetros mais acentuados nas atletas com maior tempo de treinamento.(AU)
Background: Intense continuous exercise provokes adaptive remodeling phenotypes in athletes, the parameters of which can be evaluated through conventional echocardiography and myocardial deformation. We compared myocardial remodeling in female athletes (athlete group) with sedentary women of the same age range (control group) and between older and younger athletes. Methods: A total of 57 female soccer players and 25 healthy sedentary women were selected. The athlete group was subdivided into a main group and those under 17 years of age (< 17 group). The dimensions and systolic and diastolic function of the cardiac chambers and myocardial deformation (longitudinal and circumferential, as well as radial strain and rotational mechanics) was determined through echocardiography, using the Z statistic with a significance level of p< 0.05. Results: The mean age of the athlete, control, main, and < 17 groups was 22.1 (SD, 6.3); 21.2 (SD, 5.0); 26.5 (SD, 5.1); 16.5 (SD, 0.6) years, respectively. Weight, body mass index and heart rate were lower in the athlete group. Wall thickness, left ventricular mass index, left atrial (LA) volume, ejection fraction, and right ventricular dimensions were higher in athlete group, but remained within normal ranges. Regarding myocardial deformation, there was decreased radial strain, basal rotation, apical rotation, and twisting in the athlete group, suggesting a contractile reserve mechanism. These parameters were lesser in the main athlete group, who also had greater wall thickness, greater volume in the left atrium (LA) and larger size in the right ventricle (RV), suggesting that increased contractile reserve is related to longer time spent in the sport. Conclusions: In female athletes who had undergone intense long-term training, we observed adaptive remodeling of the cardiac chambers and increased contractile reserve (at rest), and these changes were more pronounced in those with longer involvement in the sport.(AU)
Subject(s)
Humans , Female , Adolescent , Adult , Athletes , Atrial Remodeling/physiology , Heart/physiopathology , Heart/diagnostic imaging , Echocardiography/methods , Sedentary Behavior , High-Intensity Interval Training/adverse effects , Global Longitudinal Strain/radiation effectsABSTRACT
Resumo Fundamento Vários marcadores têm sido avaliados quanto a um potencial impacto nas decisões clínicas ou na predição de mortalidade na síndrome coronariana aguda (SCA), incluindo Netrina-1 e IL-1β. Objetivo Examinamos o valor prognóstico de Netrina-1 e IL-1β em pacientes com SCA (2 anos de acompanhamento). Métodos Avaliamos Netrina-1, IL-1β e outros fatores de risco em amostras de soro de 803 pacientes. Curvas de Kaplan-Meier e regressão de Cox foram usadas para análise de óbito por todas as causas, óbito por doenças cardiovasculares (DCV) e desfecho combinado de infarto agudo do miocárdio (IAM) fatal ou novo IAM não fatal, considerando p < 0,05. Resultados Houve 115 óbitos por todas as causas, 78 óbitos por DCV e 67 eventos no desfecho combinado. Níveis de Netrina-1 acima da mediana (> 44,8 pg/mL) foram associados a pior prognóstico (óbito por todas as causas e por DCV) em mulheres idosas, mesmo após o ajuste do modelo (HR: 2,08, p = 0,038 e HR: 2,68, p = 0,036). Níveis de IL-1β acima da mediana (> 13,4 pg/mL) em mulheres idosas foram associados a risco aumentado para todos os desfechos após o ajuste (todas as causas - HR: 2,03, p = 0,031; DCV - HR: 3,01, p = 0,013; desfecho combinado - HR: 3,05, p = 0,029). Para homens, não foram observadas associações entre Netrina-1 ou IL-1β e os desfechos. Conclusão Níveis séricos elevados de Netrina-1 e IL-1β mostraram associação significativa com pior prognóstico em idosas do sexo feminino. Eles podem ser úteis como indicadores prognósticos em SCA. (Arq Bras Cardiol. 2020; 114(3):507-514)
Abstract Background Several markers have been evaluated for a potential impact on clinical decisions or mortality prediction in acute coronary syndrome (ACS), including Netrin-1 and IL-1β that have been associated with cardiovascular disease. Objective Our study examined the prognostic value of Netrin-1 and IL-1β in patients with ACS (2-year follow-up). Methods We evaluate Netrin-1, IL-1β and other risk factors in the serum sample of 803 patients. Kaplan-Meier curves and Cox regression were used for the analysis of all-cause mortality, cardiovascular mortality, and a combined outcome of fatal myocardial infarction (MI) or new non-fatal MI, considering p-value < 0.05. Results There were 115 deaths from all causes, 78 deaths due to cardiovascular causes and 67 events in combined outcomes. Netrin-1 levels above the median (>44.8 pg/mL) were associated with a worse prognosis (all-cause mortality and cardiovascular mortality) in elderly females, even after model adjustment (HR: 2.08, p = 0.038 and HR: 2.68, p = 0.036). IL-1β levels above the median (>13.4 pg/mL) in elderly females were associated with increased risk of all outcomes after adjustment (all-cause mortality - HR: 2.03, p = 0.031; cardiovascular mortality - HR: 3.01, p = 0.013; fatal MI or new non-fatal MI - HR: 3.05, p = 0.029). For males, no associations were observed between Netrin-1 or IL-1β and outcomes. Conclusion High serum levels of Netrin-1 and IL-1β showed significant association with worse prognosis in elderly females. They may be useful as prognostic indicators in ACS. (Arq Bras Cardiol. 2020; 114(3):507-514)
Subject(s)
Humans , Female , Aged , Interleukin-1beta/blood , Acute Coronary Syndrome , Netrin-1/blood , Prognosis , Biomarkers , Risk Factors , Follow-Up Studies , Myocardial InfarctionABSTRACT
@#Atrial fibrillation is a common arrhythmia associated with high mortality and morbidity, and the current treatment of atrial fibrillation is still limited. Histone deacetylase (HDAC) plays an important role in the pathophysiology of cardiovascular disease and promotes the occurrence of atrial fibrillation. Inhibition of HDAC may be a new therapeutic strategy through the regulation of atrial remodeling. Therefore, we reviewed the research progress of the HDAC and atrial fibrillation.
Subject(s)
Humans , Atrial Fibrillation/surgery , Catheter Ablation , Atrial Appendage , Cardiomyopathies , Heart AtriaABSTRACT
Objective@#To investigate the effects and potential mechanisms of tolvaptan on chronic intermittent hypoxia (CIH)-induced atrial remodeling in rats.@*Methods@#A total of 45 Sprague-Dawley rats were divided into 3 groups by the random number table: control group, CIH group (6 h/d for 30 days), CIH plus tolvaptan group (8 mg·kg-1·d-1 per gavage for 30 days). Echocardiography examination was performed after 30 days. Thereafter, 5 rats were randomly chosen for histology evaluation, 5 for molecular biological examinations and another 5 rats underwent isolated heart electrophysiology study in each group. Protein and mRNA expression levels of miRNA-21, Spry1, PTEN, ERK/p-ERK, MMP-9, PI3K, AKT/p-AKT were detected.@*Results@#Compared to the rats in control group, rats in the CIH group showed higher atrial interstitial collagen deposition (P<0.001), increased atrial fibrillation inducibility (P=0.022). The results of immunohistochemistry staining showed that the mean optical density (MOD) of ERK, p-ERK and MMP-9 were significantly increased (all P<0.05), the MOD of Spry1 and PTEN were significantly decreased (both P<0.05), above changes could be significantly reversed by cotreatment with tolvaptan. No significant differences were detected in PI3K and AKT among the three groups (P>0.05). In addition, compared with rats in control group, mRNA levels of miRNA-21, MMP-9, PI3K, AKT, and protein levels of ERK, p-ERK, MMP-9 were significantly increased in CIH group(all P<0.05), whereas protein levels of Spry1, PI3K, p-AKT were significantly decreased (all P<0.05). Above changes could be significantly attenuated.@*Conclusions@#CIH induces significant atrial remodeling in this rat model, which can be attenuated by tolvaptan possibly through modulating miRNA-21/Spry1/ERK/MMP-9 and miRNA-21/PTEN/PI3K/AKT signaling pathways.
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Objective To investigate the clinical efficacy and mechanism of rosuvastatin combined with telmisartan in the treatment of persistent atrial fibrillation. Methods One hundred and twenty patients with persistent atrial fibrillation admitted to Cangzhou Central Hospital from February 2015 to February 2018 were enrolled and they were divided into study group and control group by random envelope method, with 60 patients in each group. The patients in study group were treated with rosuvastatin combined with telmisartan; and in control group they were treated with telmisartan, and after treatment for 6 weeks the clinical efficacy was observed. Resting heart rates were observed in two groups. The left atrial inner diameter, left atrium left and right diameter, left atrial sphericity index and left ventricular end diastolic volume, left ventricular end systolic volume, left ventricular posterior wall thickness of two groups were detected by ultrasond before and after treatment; the levels of serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were tested by enzyme linked immunosorbent assay (ELISA) in two groups before and after treatment; and the level of serum hypersensitive C-reactive protein (hs-CRP) was detected by immunoturbidimetry;the level of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) was tested by immunoluminometric assay. Results Resting heart rate was significantly decreased in study group after treatment compared with that before treatment (bpm: 76.37±7.25 vs. 89.76±8.79, P < 0.05), while in control group, the comparison of resting heart rate before and after treatment was of no statistical significant differences (bpm: 90.71±8.56 vs. 87.80±6.26, P > 0.05), resulting that the post-treatment resting heart rate of study group was significantly lower than that of control group (bpm:76.37±7.25 vs. 87.80±6.26, P < 0.05). After treatment, the left atrial inner diameter, left atrium left and right diameter, left atrial sphericity index and left ventricular end diastolic volume were increased compared with those before treatment in both groups; after treatment, above various index levels in study group were lower than those of control group [left atrial inner diameter (mm): 40.68±3.86 vs. 41.99±3.97, left atrium left and right diameter (mm): 41.07±2.85 vs. 42.69±2.90, left atrial sphericity index: 0.77±0.08 vs. 0.86±0.07, left ventricular end diastolic volume (mL): 107.48±32.90 vs. 118.98±35.75, all P < 0.05]. There were no statistical significant differences between the two groups in left ventricular end systolic volume and posterior wall thickness of left ventricle after treatment [study group: left ventricular end systolic volume (mL) was 38.59±12.37 vs. 39.81±12.03, posterior wall thickness of left ventricle (mm) was 11.34±2.39 vs. 12.80±3.27, control group: left ventricular end systolic volume (mL) was 39.90±11.54 vs. 40.65±11.50, posterior wall thickness of left ventricle (mm) was 11.90±2.57 vs. 12.99±3.16, all P > 0.05]. Besides, the serum levels of TNF-α, IL-6 and hs-CRP were obviously decreased in two groups after treatment (all P < 0.05), after treatment, above indexes in study group were significantly lower than those in control group [TNF-α (ng/L): 29.76±5.31 vs. 36.63±5.11, IL-6 (ng/L): 14.37±3.36 vs. 22.65±4.58, hs-CRP (mg/L): 13.68±2.75 vs. 20.63±2.69, all P < 0.05]. Plasma NT-proBNP was increased in control group after treatment compared with that before treatment (μg/L: 431.80±42.54 vs. 365.89±39.81, P < 0.05), whereas there was no significant difference in the study group between pre- and post-treatment (μg/L: 351.80±38.76 vs. 346.89±35.82, P > 0.05), resulting in post-treatment plasma NT-proBNP significantly lower in study group (P < 0.05). Conclusions Rosuvastatin combined with telmisartan can prevent left atrial remodeling in patients with persistent atrial fibrillation and delay the dysfunction of left ventricular pump. The therapeutic mechanism was related to the decrease in the levels of serum inflammatory factors in patients treated with such therapy.
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Objectives: To evaluate the changes of left atrial volume (LAV) and the maximum ostial cross-sectional area (CAS) of pulmonary vein (PV) in atrial fibrillation (AF) patients after circumferential pulmonary vein isolation radiofrequency catheter ablation (CPVA-RFCA) and to explore their relationship to AF recurrence by enhanced cardiac MRI evaluation. Methods: Our research included in 2 groups: Control group, n=20 healthy subjects and AF group, n=78 patients whom were classified into 2 subgroups as Paroxysmal AF subgroup, n=46 and Persistent AF subgroup, n=32; 66 patients received CPVA-RFCA and based on 6 months post-operative recurrence, they were divided into another set of 2 groups: AF recurrent subgroup, n=17 and Non-AF recurrent subgroup, n=49. Pre- and 6 months post-operative maximum ostial CSA of PV were measured by enhanced cardiac MRI, LAV were obtained by 3D reconstruction and the differences were compared between AF group and Control group, Paroxysmal AF subgroup and Persistent AF subgroup, AF recurrent subgroup and Non-AF recurrent subgroup; their relationships to AF recurrence were studied.Results: Compared with Control group, AF group had increased LAV and elevated ostial CSA of superior PV (SPV), both P<0.05. Compared with Paroxysmal AF subgroup, Persistent AF subgroup had increased LAV and elevated ostial CSA of SPV, both P<0.05. Compared with pre-operative condition, at 6 months after the operation, Non-AF recurrent subgroup showed reduced ostial CSAs in left SPV (LSPV), right SPV (RSPV), right inferior PV (RIPV) and decreased LAV, all P<0.05;while AF recurrent subgroup showed expanded RSPV and increased LAV,allP<0.05.Post-operative reductions of LAV and ostial CSA of SPV had close correlation; multivariate Logistic regression analysis indicated that LAV (HR=1.05, P<0.01)and ostial CSA of RSPV(HR=1.09,P=0.05)were related to AF recurrence after RFCA. Conclusions: CAPV-RFCA could reverse left atrial and PV remodeling in AF patients, LAV and ostial CSA of RSPV were related to post-operative AF recurrence.
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Atrial fibrillation (AF) is the most common tachyarrhythmia in clinical practice. Owing to its high morbidity and mortality, early diagnosis of AF plays an important clinical significance in treatment and prognosis. Galectin-3 (Gal-3), as a sensitive marker of inflammatory and oxidative stress found in recent years, is involved in the occurrence and development of myocardial inflammation and fibrosis, which is closely related to atrial remodeling. Gal-3 inhibitor may decrease the risk of AF by reversing myocardial remodeling, which may provide a new theoretical basis and research direction for the upstream treatment of AF.
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Atrial structural remodeling and electrical remodeling are the core of atrial fibrillation.Oxidative stress directly activates calcium/calmodulin-dependent protein kinase Ⅱ (CaMKⅡ), and induces electrical remodeling and atrial structural remodeling characterized by reduced atrial effective refractory period, which becomes the pathological basis of atrial fibrillation.Therefore, the study of the relationship between the oxidative CaMKⅡ and atrial remodeling will help to elucidate the pathogenesis of atrial fibrillation and to prevent or reverse atrial remodeling by lowering CaMKⅡ phosphorylation to reduce the incidence of atrial fibrillation.
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Atrial fibrillation (AF) is one of the most common arrhythmias in clinical practice.It often causes serious thromboembolic complications,which brings great harm to human health.The incidence and morbidity rates of AF are increasing year by year.The research on the pathogenesis of AF has been focused on the aspects of electrical remodeling and structural remodeling.Atrial electrical remodeling and structural remodeling are the main mechanism of AF for the maintenance and recurrence.The intervention of atrial remodeling is helpful to the treatment of AF.It is found that the rennin-angiotensin aldosterone system (RAAS) plays an important role in atrial remodeling.RAAS blockers can significantly reduce the onset of AF by inhibiting the activation of the renin axis,which can block the activation of RAAS and improve the atrial remodeling.This may provide a new choice for the treatment of AF.This article reviews the research progress of RAAS blocking agent in the prevention and treatment of AF.
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Objective:To investigate the expression of fibrillin-1 (FBN-1) in the atrium tissue of the patients with rheumatic heart valve disease complicated with atrial fibrillation(AF), and to explore its relationship with atrial fibrosis in the patients with valvular atrial fibrillation.Methods:Eighty-four consecutive patients with rheumatic heart valve disease underwent cardiac surgery were enrolled in this study.The patients were divided into AF group(n=39) and sinus rhythm group(SR group, n=45).The clinical data of patients were collected before operation.The right atrium tissue (0.3-0.5 mm3) was disserted during operation.The degrees of right atrial fibrosis of the patients in two groups were observed by Masson staining.Western blotting method was used to measure the protein expressions of FBN-1 in atrium tissue of the patients in two groups.Results:There were no significant differences in the gender ratio, age, blood pressure, blood biochemical indicators and other aspects of medical history between two groups(P>0.05);the diameters of left and right atrium of the patients in AF group were significantly larger than those in SR group(P<0.05).The Masson staining results showed that there was obvious fibrosis in AF group, and the collagen volume fraction and collagen level in AF group were significantly higher than those in SR group (P<0.05).The expression level of FBN-1 in right atrium tissue in AF group was obviously higher than that in SR group(P<0.05).The expression level of FBN-1 protein in right atrium tissue of the patients with valvular atrial fibrillation was positively correlated with the collagen level(r=0.544,P=0.021).Conclusion:There is obvious atrium fibrosis in the patients with valvular atrial fibrillation;it is closely related to the up-regulation of the expression of FBN-1 gene.
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Objective To investigate the expression of α-smooth muscle actin (α-SMA)in patients with valvular atrial fibrillation and study the relationship betweenα-SMA and atrial fibrosis in patients with valvular atrial fibrillation (AF).Methods For this study we enrolled 84 consecutive patients with rheumatic heart disease who were to receive cardiac surgery.The patients were divided into AF group (AF,n=39)and sinus rhythm group (SR, n=45).Their clinical data including baseline demographics,routine laboratory test and echocardiographics were collected before surgery.The right atrial tissue (0 .3-0 .5 cm3 )was disserted during the surgery.Right atrial fibrosis was observed by Masson staining.The mRNA expression ofα-SMA in atrial tissue were determined by Real-time quantitative PCR.Western blot was used to measure the protein expression ofα-SMA in atrial tissue.Results The two groups did not significantly differ in sex ratio,age,blood pressure,blood biochemical indicators or other aspects of medical history (P>0.05).However,left and right atrium diameters in AF group were significantly larger than those in SR group (P<0 .05 ).Masson staining suggested that collagen volume fraction and collagen content were significantly higher in AF group than in SR group (P<0 .05 ).The mRNA and protein expressions ofα-SMA in right atrial tissue were obviously higher in AF group than in SR group (coefficients P<0 .05 ).The mRNA and protein expressions ofα-SMA from right atrial tissue in the 84 patients were positively correlated with collagen content (coefficients of 0.587 and 0.607;P=0.029,0.014,respectively).Conclusion There is significant atrial fibrosis in patients with valvular atrial fibrillation,which is closely related to up-regulated expression ofα-SMA gene.
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BACKGROUND AND OBJECTIVES: This study aimed to evaluate the impact of the CHA₂DS₂-VASc score on atrial fibrillation (AF) recurrence after a single catheter ablation procedure in patients with non-valvular AF. We also investigated the correlation between CHA₂DS₂-VASc score and atrial substrate. SUBJECTS AND METHODS: This study evaluated 151 patients who underwent catheter ablation of non-valvular AF. The study population was stratified into group 1 (<2, n=72) and group 2 (≥2, n=79) by CHA₂DS₂-VASc score. The CHA₂DS₂-VASc score was analyzed as a continuous and categorical value for evaluating its impact on AF recurrence after catheter ablation. The left atrial voltage data were analyzed by the categorical values of this score. RESULTS: Post-ablation recurrence (31.6% vs. 18.1%, p=0.046) was observed more frequently in group 2. The mean area of the lowvoltage zone was 75.64±24.81 cm² and 94.44±28.09 cm² in groups 1 and 2, respectively (p=0.005). The left atrial mean voltage in group 2 was 0.99±0.31 mV, significantly lower than that (1.49±0.67 mV, p=0.001) in group 1. The CHA₂DS₂-VASc score was the independent predictor with a modest predictive value for AF recurrence after catheter ablation. CONCLUSION: Our study showed that CHA₂DS₂-VASc score was associated with atrial remodeling and could be useful in stratifying post-ablation recurrence in patients with non-valvular AF.
Subject(s)
Humans , Atrial Fibrillation , Atrial Remodeling , Catheter Ablation , Catheters , RecurrenceABSTRACT
Influenced by a variety of pathologic factors, cardiac fibroblasts can transdifferentiate into myofibroblasts and pro-liferate excessively, followed by an overdue secretion of extracellular matrix ( ECM) .This process involves complicated signaling path-ways and electrophysiological mechanisms and may result in atrial fibrosis and contribute to atrial remodeling in structure, function and electrophysiological signaling, which is considered as a most important phase of atrial fibrillation.This review focuses on the role of fi-broblasts in atrial fibrosis, atrial remodeling, and the development of atrial fibrillation.
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BACKGROUND/AIMS: There have been reports that interatrial septal (IAS) thickness is increased in patients with atrial fibrillation (AF). This study was performed to investigate whether IAS thickness determined by transthoracic echocardiography (TTE) represents the amount of left atrium (LA) structural and functional remodeling. METHODS: The study population consisted of 104 consecutive patients who underwent catheter ablation (CA) for AF (paroxysmal atrial fibrillation [PAF], 82; persistent atrial fibrillation [PeAF], 22). IAS thickness and left atrium volume (LAV) using TTE, and LA voltage (LAVOL) using 3-dimensional electroanatomical mapping system were assessed during sinus rhythm. RESULTS: IAS thickness was significantly correlated with maximal LAV (LAVmax) (r = 0.288, p = 0.003), mean LAVOL (r = -0.537, p or = 2) compared to other groups according to CHA2DS2-VASc score (p = 0.019). During a follow-up of 19.6 months, 23 subjects (22.1%; PAF, 17; PeAF, 6) had recurrence of arrhythmia. Univariate analysis showed that LAVmax, minimal LAV, mean LAVOL, LVEFtotal, LVEFactive, and IAS thickness were associated with recurrence of arrhythmia. However, on multivariate analysis, only mean LAVOL and LAEFactive were independent risk factors for recurrence. CONCLUSIONS: Although IAS thickness showed significant correlations with parameters for LA structural and functional remodeling, this parameter alone could not independently predict recurrence of arrhythmia after CA for AF.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Action Potentials , Area Under Curve , Atrial Fibrillation/physiopathology , Atrial Function, Left , Atrial Remodeling , Atrial Septum/physiopathology , Catheter Ablation , Chi-Square Distribution , Echocardiography, Doppler , Electrophysiologic Techniques, Cardiac , Linear Models , Multidetector Computed Tomography , Multivariate Analysis , Predictive Value of Tests , Prospective Studies , ROC Curve , Recurrence , Risk Factors , Time Factors , Treatment OutcomeABSTRACT
PURPOSE: Recently, mitochondrial DNA 4977bp deletion (mtDNA4977-mut), a somatic mutation related to oxidative stress, has been shown to be associated with atrial fibrillation (AF). We hypothesized that patient age, as well as electroanatomical characteristics of fibrillating left atrial (LA), vary depending on the presence of mtDNA4977-mut in peripheral blood among patients with non-valvular AF. MATERIALS AND METHODS: Analyzing clinical and electroanatomical characteristics, we investigated the presence of the mtDNA4977-mut in peripheral blood of 212 patients (51.1+/-13.2 years old, 83.5% male) undergoing catheter ablation for non-valvular AF, as well as 212 age-matched control subjects. RESULTS: The overall frequency of peripheral blood mtDNA4977-mut in patients with AF and controls was not significantly different (24.5% vs. 19.3%, p=0.197). When the AF patient group was stratified according to age, mtDNA4977-mut was more common (47.4% vs. 20.0%, p=0.019) in AF patients older than 65 years than their age-matched controls. Among AF patients, those with mtDNA4977-mut were older (58.1+/-11.9 years old vs. 48.8+/-11.9 years old, p<0.001). AF patients positive for the mtDNA mutation had greater LA dimension (p=0.014), higher mitral inflow peak velocity (E)/diastolic mitral annular velocity (Em) ratio (p<0.001), as well as lower endocardial voltage (p=0.035), and slower conduction velocity (p=0.048) in the posterior LA than those without the mutation. In multivariate analysis, E/Em ratio was found to be significantly associated with the presence of mtDNA4977-mut in peripheral blood. CONCLUSION: mtDNA4977-mut, an age-related somatic mutation detected in the peripheral blood, is associated with advanced age and electro-anatomical remodeling of the atrium in non-valvular AF.