The latest medical research on Atrial Fibrillation

The research magnet gathers the latest research from around the web, based on your specialty area. Below you will find a sample of some of the most recent articles from reputable medical journals about atrial fibrillation gathered by our medical AI research bot.

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Association between Hemoglobin A1c and Renal Arteriolar Sclerosis in Subjects Presenting without any Apparent Kidney Dysfunction.

Atherosclerosis

Diabetic kidney disease is a major vascular complication in patients with diabetes mellitus (DM). However, the association between the hemoglobin (Hb)A1c levels, notably the prediabetic levels, and renal pathological changes remains unclear. We investigated the association between the HbA1c levels and renal arteriolar lesions in subjects without any apparent kidney dysfunction using a living kidney donor cohort.

Between January 2006 and May 2016, 393 living kidney donors underwent a "zero-time" biopsy at Kyushu University Hospital. The patients were divided into four groups (HbA1c levels <5.6%, 5.6%-5.7%, 5.8%-6.4%, and ≥ 6.5%, or diagnosed with DM [DM group]). Renal arteriolar hyalinization and wall thickening were assessed using semi-quantitative grading. We then investigated the association between the HbA1c levels and renal pathological changes.

158 (40.2%) patients had arteriolar hyalinization and 148 (37.6%) showed wall thickening. A significant correlation was observed between the HbA1c levels and wall thickening (p for trend <0.001). An elevated HbA1c level was significantly associated with wall thickening according to a multivariable logistic analysis in subjects with HbA1c levels of 5.6%-5.7% and 5.8%-6.4%, and the DM group, compared with those with HbA1c levels of <5.6% (odds ratio [OR], 1.91; 95% confidence interval [CI]: [1.03-3.54] for 5.6%-5.7%, OR, 1.96; 95% CI: [1.09-3.53] for 5.8%-6.4%, and OR, 2.86; 95% CI: [0.91-9.01] for the DM group), whereas arteriolar hyalinization did not increase within the nondiabetic HbA1c levels.

Elevated high-normal HbA1c levels are considered to be independent risk factors for arteriolar wall thickening. Subclinical renal arteriolar sclerosis may develop in patients with prediabetic HbA1c levels.

Identification of a Compound Heterozygous LMF1 Variants in a Patient with Severe Hypertriglyceridemia - Case Report and Literature Review.

Atherosclerosis

Familial chylomicronemia syndrome (FCS) and multifactorial chylomicronemia (MCM), characterized by highly variable triglyceride levels with acute e...

Association between Vascular Calcification and Intraplaque Hemorrhage in Coronary Atherosclerosis from Autopsy: The Hisayama Study.

Atherosclerosis

Vascular calcification is observed in advanced atherosclerotic lesions. Vascular calcification is considered to increase the risk of intraplaque hemorrhage and subsequent plaque destabilization; however, there is limited pathohistoological evidence of the association between vascular calcification and intraplaque hemorrhage. The aim of this study was to investigate the association between vascular calcification and intraplaque hemorrhage in the coronary arteries.

We examined 374 coronary arteries obtained from the autopsy samples of 126 deceased individuals. The vascular calcification levels of each artery were categorized into no calcification and quintiles of calcification area size among the arteries with calcification. Macrophage infiltration and neovascularization were also evaluated. The association of the calcification area, macrophage area, or number of vessels with the presence of intraplaque hemorrhage in the coronary arteries was estimated using a logistic regression analysis.

Calcification lesions were observed in 149 coronary arteries. Arteries in the fourth quintile of calcification area size had a significantly greater likelihood of intraplaque hemorrhage than the arteries without calcification, after adjusting for confounders: odds ratio 13.13 (95% confidence interval: 2.97-58.16). After evaluating the influence of macrophage infiltration, the highest odds ratio of intraplaque hemorrhage was associated with the combination of large macrophage area and moderately sized calicification areas. The odds ratio of intraplaque hemorrhage additively increased with the combination of calcification and the number of vessels.

The present findings suggest that vascular calcification is significantly associated with intraplaque hemorrhage. The association between vascular calcification and intraplaque hemorrhage may decrease above a certain size of the calcification area.

Intima-Media Thickness in the Carotid Bifurcation is Related to Silent Brain Infarction: A Cross-Sectional Study.

Atherosclerosis

Carotid intima-media thickness (IMT) measurement is used to assess subclinical atherosclerosis. We aimed to examine the association between the maximum IMT by location and the occurrence of silent brain infarction (SBI).

Overall, 280 Japanese individuals (92 females, 52.6±5 years old) underwent a medical check-up at our hospital in Tokyo in 2015. Carotid IMT was measured at each site on ultrasound images (common carotid artery [CCA], internal carotid artery, or bifurcation). The risk factors for arterial dysfunction were evaluated. SBI was assessed using magnetic resonance imaging (MRI). The cross-sectional relationship between carotid maximum IMT and SBI was evaluated.

Of the 280 individuals, 18 (6.4%) were diagnosed with SBI on MRI. The mean age of the SBI(-) and SBI(+) groups was 51.9±10.6 and 63.6±18.6 years, respectively. The correlation coefficients between the carotid maximum IMT at each location were very weak (correlation coefficient range: 0.180-0.253). The percentage of participants with SBI increased significantly with increasing maximum CCA and bIMT values. After adjusting for confounders, SBI was found to be significantly associated with the maximum bIMT (per 0.1-mm increase) (adjusted odds ratio [aOR], 1.10; 95% confidence interval [CI]: 1.03-1.17). When bIMT was categorized according to three groups (<1.0 mm, 1.0-<2.0 mm, and ≥ 2.0 mm), a significant SBI risk was also observed with an increase by each category of bIMT (aOR: 3.96, 95% CI: 1.63-9.52, P=0.002).

The maximum bIMT was found to be the main determinant of SBI. A significant SBI risk was associated with an increase in each category of the maximum bIMT. Therefore, the maximum bIMT might be a useful predictor of future stroke in Japanese stroke-free medical check-up participants.

Elevated Leukocyte Count and Platelet-Derived Thrombogenicity Measured Using the Total Thrombus-Formation Analysis System in Patients with ST-Segment Elevation Myocardial Infarction.

Atherosclerosis

High platelet-derived thrombogenicity during the acute phase of ST-segment elevation myocardial infarction (STEMI) is associated with poor outcomes; however, the associated factors remain unclear. This study aimed to examine whether acute inflammatory response after STEMI affects platelet-derived thrombogenicity.

This retrospective observational single-center study included 150 patients with STEMI who were assessed for platelet-derived thrombogenicity during the acute phase. Platelet-derived thrombogenicity was assessed using the area under the flow-pressure curve for platelet chip (PL-AUC), which was measured using the total thrombus-formation analysis system (T-TAS). The peak leukocyte count was evaluated as an acute inflammatory response after STEMI. The patients were divided into two groups: the highest quartile of the peak leukocyte count and the other three quartiles combined.

Patients with a high peak leukocyte count (>15,222/mm3; n=37) had a higher PL-AUC upon admission (420 [386-457] vs. 385 [292-428], p=0.0018), higher PL-AUC during primary percutaneous coronary intervention (PPCI) (155 [76-229] vs. 96 [29-170], p=0.0065), a higher peak creatine kinase level (4200±2486 vs. 2373±1997, p<0.0001), and higher PL-AUC 2 weeks after STEMI (119 [61-197] vs. 88 [46-122], p=0.048) than those with a low peak leukocyte count (≤ 15,222/mm3; n=113). The peak leukocyte count after STEMI positively correlated with PL-AUC during primary PPCI (r=0.37, p<0.0001). A multivariable regression analysis showed the peak leukocyte count to be an independent factor for PL-AUC during PPCI (β=0.26, p=0.0065).

An elevated leukocyte count is associated with high T-TAS-based platelet-derived thrombogenicity during the acute phase of STEMI.

Age- and Gender-Specific Reference Intervals for the Fasting Serum Lipid Levels in a Pediatric Population Aged 0-<15 Years in Nanjing, China.

Atherosclerosis

The lipid reference intervals (RIs) that are currently used for children in China are not based on studies of the local population and normally do not consider age or gender differences. This study aimed to establish age- and sex-specific RIs for the fasting serum lipid levels in the pediatric population aged 0 - 15 years in Nanjing, China.

5,866 children aged 3 days to <15 years were recruited to establish serum lipid RIs, and the triglyceride (TG), total cholesterol (TC), and high-density lipoprotein cholesterol (HDL-C) levels were analyzed using the Roche cobas702 automatic biochemical analyzer. Low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (nHDL-C) levels were calculated (LDL-C=TC-HDL-C-TG/5, and nHDL-C=TC-HDL-C). Smoothed percentile curves for the boys and girls were generated using the LMS method. Age- and sex-specific RIs were the determined according to the methods recommended by the Clinical and Laboratory Standards Institute EP28-A3c guidelines.

This study showed that the serum lipid levels varied considerably throughout childhood and adolescence, with sex differences, especially in infants aged less than 2 years and puberty. Based on the Harris-Boyd method, sex partitions were required for ages <6 months in the TC indicator and for ages ≤ 28 days in LDL-C and nHDL-C. Age partitions were also required for all serum lipid parameters.

We established age- and sex-specific RIs for TG, TC, HDL-C, LDL-C, and nHDL-C parameters in children aged 0 days to <15 years in Nanjing, China. These data are thus considered to be useful for the screening of dyslipidemia in children and adolescents.

The Risk of Coronary Artery Calcification according to Different Lipid Parameters and Average Lipid Parameters.

Atherosclerosis

We compared the association between the baseline and average lipid parameters over time and the coronary artery calcification (CAC) risk.

Participants who underwent annual (biannual) health examinations and coronary artery computed tomography to measure CAC at least twice between March 2010 and December 2019, with a baseline CAC of 0, were included. The levels of apolipoprotein B (ApoB), Apolipoprotein A-I (ApoA1), ApoB/ApoA1, non-high-density lipoprotein cholesterol (non-HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TG), TG/HDL-C, and TC/HDL-C were measured or calculated. The remnant cholesterol (RC) levels were calculated. The average lipid parameters before study entry were calculated using data from 2002 to 2010. The participants were divided into quartiles (Q) according to the parameter values. Cox proportional hazard modeling, adjusted for confounding factors, compared the CAC risk of the highest quartile to the lowest quartile.

Among 29,278 participants (mean age, 39.19±5.21; men, 88.27%), 2,779 developed CAC >0. The highest quartile of ApoB showed a numerically strong association with CAC risk, compared with the lowest quartile of ApoB (Q1: reference; Q2: HR,1.41, 95% CI,1.25-1.59; Q3: HR,1.97, 95% CI,1.75-2.21; Q4: HR,2.72, 95% CI,2.41-3.07). RC showed a modest association with CAC risk (Q1: reference; Q2: HR,1.13, 95% CI,0.99-1.28; Q3: HR,1.3, 95% CI,1.15-1.47; Q4: HR,1.7, 95% CI,1.51-1.91). The strength of the association was comparable between the parameters at baseline and the average lipid parameters over time.

A high ApoB level showed a strong association with CAC risk compared with the lowest ApoB quartile. The baseline lipid parameters can predict CAC development as effectively as the average of multiple measurements can.

Polygenic Risk Scores in Predicting Coronary Artery Disease in Symptomatic Patients. A Validation Study.

Atherosclerosis

Clinical risk scores for coronary artery disease (CAD) are used in clinical practice to select patients for diagnostic testing and therapy. Several studies have proposed that polygenic risk scores (PRSs) can improve the prediction of CAD, but the scores need to be validated in clinical populations with accurately characterized phenotypes. We assessed the predictive power of the three most promising PRSs for the prediction of coronary atherosclerosis and obstructive CAD.

This study was conducted on 943 symptomatic patients with suspected CAD for whom the phenotype was accurately characterized using anatomic and functional imaging. Previously published genome-wide polygenic scores were generated to compare a genetic model based on PRSs with a model based on clinical data. The test and PRS cohorts were predominantly Caucasian of northern European ancestry.

All three PRSs predicted coronary atherosclerosis and obstructive CAD statistically significantly. The predictive accuracy of the models combining clinical data and different PRSs varied between 0.778 and 0.805 in terms of the area under the receiver operating characteristic (AUROC), being close to the model including only clinical variables (AUROC 0.769). The difference between the clinical model and combined clinical + PRS model was not significant for PRS1 (p=0.627) and PRS3 (p=0.061). Only PRS2 slightly improved the predictive power of the model (p=0.04). The likelihood ratios showed the very weak diagnostic power of all PRSs.

The addition of PRSs to conventional risk factors did not clinically significantly improve the predictive accuracy for either coronary atherosclerosis or obstructive CAD, showing that current PRSs are not justified for routine clinical use in CAD.

Impaired Cholesterol Efflux Capacity rather than Low HDL-C Reflects Oxidative Stress under Acute Myocardial Infarction.

Atherosclerosis

Acute myocardial infarction (AMI) causes irreversible damage to cardiomyocytes due to the discontinuation of oxygen supply and leads to systemic oxidative stress. It has been reported that high-density lipoprotein (HDL) particles have antioxidant capacity, and reduced antioxidant capacity is associated with decreased cholesterol efflux capacity (CEC). The purpose of this study was to clarify the usefulness of CEC measurement in patients with AMI.

We investigated the association between CEC and oxidative stress status in a case-control study. This study included 193 AMI cases and 445 age- and sex-matched controls. We examined the associations of CEC with HDL-cholesterol (HDL-C) and oxidized human serum albumin (HSA), an index of systemic oxidative stress status, and the effect of aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism, which has been reported to affect HDL-C level and risk for MI, on these associations.

Both bivariable and multivariable analyses showed that CEC was positively correlated with HDL-C levels in both AMI cases and controls, with a weaker correlation in AMI cases than in controls. In AMI cases, oxidized HSA levels were associated with CEC in both bivariable and multivariable analyses, but not with HDL-C. These associations did not differ among the ALDH2 genotypes.

CEC, but not HDL-C level, reflects systemic oxidative stress status in patients with AMI. CEC measurement for patients with AMI may be useful in that it provides information on systemic oxidative stress status as well as atherosclerosis risk.

Low-Density Lipoprotein Cholesterol to Triglyceride Ratio and Clinical Outcomes after Acute Ischaemic Stroke or Transient Ischaemic Attack.

Atherosclerosis

Studies showed that low-density lipoprotein cholesterol (LDL-C) to triglyceride (TG) ratio could be used as a predictive parameter of low-density lipoprotein oxidation in vivo and the level of small dense LDL-C. However, whether LDL-C/TG ratio is associated with stroke prognosis remains unclear. We investigated the associations of LDL-C/TG ratio with outcomes in patients with acute ischaemic stroke (AIS) or transient ischaemic attacks (TIA) and explored whether it produced more predictive value than LDL-C and TG.

Data were derived from the Third China National Stroke Registry (CNSR-III). Multivariable Cox regression for stroke recurrence, composite vascular events and all-cause death and logistic regression for the poor functional outcome (modified Rankin Scale score 3-6) were used.

A total of 14123 patients were included. After adjusting for confounding factors, quartile 4 of LDL-C/TG ratio was associated with an increased risk of recurrent stroke (hazard ratio [HR], 1.27; 95% confidence interval [CI], 1.03-1.56), composite vascular events (HR,1.23; 95% CI, 1.00-1.52), death (HR,1.70; 95% CI, 1.13-2.54) and poor functional outcome (odds ratio, 1.34; 95% CI, 1.12-1.61) at 3 months follow-up compared with quartile 1. We also found that quartile 4 of LDL-C and TG was positively and negatively associated with poor functional outcome at 3 months, respectively. LDL-C/TG ratio performed better than LDL-C or TG in predicting clinical outcomes.

LDL-C/TG ratio was associated with the risk of stroke recurrence, composite vascular events, death and poor functional outcome in patients with AIS or TIA.

Unfractionated Heparin Safety in COVID-19: Incidence and Risks of Bleeding Complications in Japan.

Atherosclerosis

Several studies have shown the efficacy and safety of low-molecular-weight heparin use in coronavirus disease 2019 (COVID-19), but that of unfractionated heparin (UFH) has not been investigated. We investigated the prevalence of bleeding complications during UFH administration, its impact on mortality, and the risk factors of bleeding outcomes associated with UFH.

This retrospective cohort study was conducted at a single-center tertiary care hospital, including hospitalized patients with COVID-19. The primary outcomes were measured as the prevalence of bleeding complications during hospitalization, and the secondary outcomes were thromboembolic events and 60-day mortality rates. Logistic regression analysis and propensity score matching were used to assess risk factors for bleeding complications and their impact on mortality.

Among 1035 included patients, 516 patients were treated with UFH. Twelve (2.3%) patients in the UFH group experienced major bleeding. The prevalence of major bleeding in patients treated with therapeutic-dose UFH was 9.2%. Logistic regression analysis showed that age ≥ 60 years (adjusted odds ratio [aOR], 3.89; 95% confidence interval [CI], 1.01-15.0; P<.05) and COVID-19 severity (aOR, 35.9; 95% CI, 4.57-282; P <.05) were associated with major bleeding complications. After propensity score matching, 11 major and 11 non-major bleeding cases (including minor bleeding) were matched. The 60-day cumulative mortality rate between the two groups did not differ significantly (P=.13, log-rank test).

The incidence of major bleeding in COVID-19 patients using therapeutic-dose UFH was relatively high. Critical COVID-19 and older age were risk factors for bleeding complications.

Relationships of Fat Mass Index and Fat-Free Mass Index with Low-Density Lipoprotein Cholesterol Levels in the Tohoku Medical Megabank Community-Based Cohort Study.

Atherosclerosis

Although fat mass (FM) and fat-free mass (FFM) have an impact on lipid metabolism, the relationship between different body composition phenotypes and lipid profiles is still unclear. By dividing the FM and FFM by the square of the height, respectively, the f at mass index (FMI) and fat-free mass index (FFMI) can be used to determine the variations in body composition. This study aimed to investigate the relationship of combined FMI and FFMI with low-density lipoprotein cholesterol (LDL-C) levels.

This cross-sectional study comprised 5,116 men and 13,630 women without cardiovascular disease and without treatment for hypertension, and diabetes. Following sex-specific quartile classification, FMI and FFMI were combined into 16 groups. Elevated LDL-C levels were defined as LDL-C ≥ 140 mg/dL and/or dyslipidemia treatment. Multivariable logistic regression models were used to examine the relationships between combined FMI and FFMI and elevated LDL-C levels.

Overall, elevated LDL-C levels were found in 1,538 (30.1%) men and 5,434 (39.9%) women. In all FFMI subgroups, a higher FMI was associated with elevated LDL-C levels. Conversely, FFMI was inversely associated with elevated LDL-C levels in most FMI subgroups. Furthermore, the groups with the highest FMI and lowest FFMI had higher odds ratios for elevated LDL-C levels than those with the lowest FMI and highest FFMI.

Regardless of FFMI, FMI was positively associated with elevated LDL-C levels. Conversely, in the majority of FMI subgroups, FFMI was inversely associated with elevated LDL-C levels.