Hemoglobin A1c and risk of left atrial thrombus and spontaneous echo contrast in non-valvular atrial fibrillation patients

Relation of Hemoglobin A1C Levels to Risk of Ischemic Stroke and Mortality in Patients With Diabetes Mellitus and Atrial Fibrillation

Diabetes mellitus (DM) is associated with an increased risk of complications in atrial fibrillation (AF). This study aimed to assess the incidence and risks of ischemic stroke and mortality according to baseline HbA1c levels in patients with DM and AF. We conducted a cohort study using Clalit Health Services electronic medical records. The study population included all Clalit Health Services members aged ≥25 years, with the first diagnosis of AF between January 1, 2010, and December 31, 2016, who had a diagnosis of DM. The risk of stroke and all-cause death were compared according to HbA1c levels at the time of AF diagnosis: <7.0%, between 7% and 9%, and ≥9%. A total of 44,451 patients with DM and AF were identified. The median age was 75 years (interquartile 65 to 83), and 52.5% were women. During a mean follow-up of 38 months, higher levels of HbA1c were associated with an increased risk of stroke with a dose-dependent response when compared with patients with HbA1c <7% (Adjusted hazard ratio [aHR] =1.30 [95% confidence interval 1.10 to 2.05] for levels between 7% and 9% and 1.60 (95% confidence interval 1.25 to 2.03) for HbA1c >9%, even after adjusting for CHA₂DS₂-Vasc risk factors and use of oral anticoagulants. The risk for overall mortality was significantly higher in the HBA1C >9% group (aHR = 1.17 [1.07 to 1.28]). In conclusion, in this cohort of patients with AF and DM, HbA1c levels were associated with the risk of stroke in a dose-dependent manner even after accounting for other recognized risk factors for stroke.

Increased hemoglobin A1c level associates with low left atrial appendage flow velocity in patients of atrial fibrillation

BACKGROUND AND AIMS

High hemoglobin A1c (HbAlc) level is associated with increased cardiovascular disease risk and thromboembolic events [1]. The study sought to explored the association between HbAlc and left atrial appendage flow velocity (LAAV) among non-valvular atrial fibrillation (AF) patients.

METHODS AND RESULTS

A total of 249 consecutive non-valvular AF patients who underwent transesophageal echocardiography (TEE) were divided into two subgroups according to the median of LAAV level (<45 cm/s, ≥45 cm/s). Blood samples and other baseline clinical data of all patients were collected and analyzed. The low LAAV group included 126 patients and the high LAAV group included 123 patients. Patients in the low LAAV group were older and had a higher percentage of persistent AF, chronic heart failure, and higher CHA2DS2-VASc score (P < 0.05). HbAlc level in the low LAAV group was significantly higher than the high LAAV group [6.1 (5.7-6.5)% vs 5.9 (5.6-6.2)%, P = 0.010]. The low LAAV group had larger left atrial diameter (LAD), left atrial area (LAA), higher left atrial pressure (LAP), and lower left ventricular ejection fraction (LVEF) (P < 0.05). Spearman rank correlation analysis showed that the HbAlc level was negatively correlated with LAAV (r = -0.211, P = 0.001). Multivariate analysis indicated that female gender (OR = 2.233, 95% CI 1.110-4.492, P = 0.024), persistent AF (OR = 6.610, 95% CI 3.109-14.052, P < 0.001), and HbAlc (OR = 1.903, 95% CI 1.092-3.317, P = 0.023) were independent factors that associated with low LAAV in AF patients.

CONCLUSION

Increased HbAlc level is associated with decreased LAAV and may reflect a low contractile function of the left atrial appendage.

The long-term efficacy and safety of combining ablation and left atrial appendage closure: A systematic review and meta-analysis

BACKGROUND

Combined ablation and left atrial appendage closure (LAAC) is an alternative for atrial fibrillation patients with a high risk of stroke. However, the long-term outcomes of this combined procedure remain elusive.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases to 1 January 2021. Studies on the long-term (defined as a mean follow-up of approximately 12 months or longer) efficacy and safety outcomes of combined ablation and LAAC were included.

RESULTS

A total of 16 studies comprising 1428 patients were enrolled. The pooled long-term freedom rate from atrial arrhythmia was 0.66 (95% confidence interval [CI]: 0.59-0.71), long-term successful rate sealing of LAAC was 1.00 (95% CI: 1.00-1.00), and ischemic stroke/transient ischemic attack/systemic embolism during follow-up was 0.01 (95% CI: 0.00-0.02). Meanwhile, of the periprocedural adverse events, phrenic nerve palsy, intracoronary air embolus, device embolization, and periprocedural death had a rate of 0.00 (95% CI: 0.00-0.00), procedure-related bleeding events of 0.03 (95% CI: 0.02-0.04), and pericardial effusion requiring or not requiring intervention of 0.00 (95% CI: 0.00-0.01). Moreover, for the long-term adverse events, device dislocation, intracranial bleeding, pericardial effusion requiring or not requiring intervention, and all-cause mortality had a rate of 0.00 (95% CI: 0.00-0.00), device embolization of 0.01 (95% CI: 0.00-0.01), and other bleeding events of 0.01 (95% CI: 0.00-0.03).

CONCLUSION

This meta-analysis suggests that the combined atrial ablation and LAAC is an effective and safe strategy with long-term benefits.

Glycemic Status and Thromboembolic Risk in Patients With Atrial Fibrillation and Type 2 Diabetes Mellitus: A Danish Cohort Study

Background Diabetes mellitus is associated with increased risk of stroke in patients with atrial fibrillation, and differences in glycemic status may affect this risk. We aimed to examine the effect of glycemic status evaluated by hemoglobin A1c (HbA1c) on the risk of thromboembolism among patients with atrial fibrillation and type 2 diabetes mellitus. Methods In this cohort study, we used data from Danish registries to identify patients with type 2 diabetes mellitus and incident nonvalvular atrial fibrillation in the period of May 1, 2005, through December 31, 2015. On the basis of the most recent HbA1c measurement before an incident atrial fibrillation diagnosis, patients were divided into the categories: HbA1c ≤48 mmol/mol, HbA1c=49-58 mmol/mol, and HbA1c >58 mmol/mol. Cox regression analysis was used to estimate hazard ratios for the outcome thromboembolism. Results The study population included 5386 patients with incident nonvalvular atrial fibrillation and type 2 diabetes mellitus. Compared with patients with HbA1c ≤48 mmol/mol, we observed a higher risk of thromboembolism among patients with HbA1c=49-58 mmol/mol (hazard ratio, 1.49; 95% CI, 1.09-2.05) and HbA1c >58 mmol/mol (hazard ratio, 1.59; 95% CI, 1.13-2.22) after adjusting for confounding factors. When stratified on diabetes mellitus duration, similar results were found among patients with diabetes mellitus duration of <10 years. Contrastingly, in patients with diabetes mellitus duration of ≥10 years, higher HbA1c levels were not associated with a higher risk of thromboembolism. Conclusions In patients with incident atrial fibrillation and type 2 diabetes mellitus, increasing levels of HbA1c were associated with a higher risk of thromboembolism. However, no association was found among patients with diabetes mellitus duration ≥10 years.

Predictive value of red cell distribution width on left atrial thrombus or left atrial spontaneous echo contrast in patients with non-valvular atrial fibrillation

OBJECTIVE

To evaluate the predictive value of red cell distribution width (RDW) on left atrial thrombus (LAT) or left atrial spontaneous echo contrast (LASEC) in patients with non-valvular atrial fibrillation (AF).

METHODS

We reviewed 692 patients who were diagnosed as non-valvular AF and underwent transesophageal echocardiography (TEE) in Guangdong Cardiovascular Institute from April 2014 to December 2015. The baseline clinical characteristics, laboratory test of blood routine, electrocardiograph measurements were analyzed.

RESULTS

Eighty-four patients were examined with LAT/LASEC under TEE. The mean RDW level was significantly higher in LAT/LASEC patients compared with the non-LAT/LASEC patients (13.59% ± 1.07% vs. 14.34% ± 1.34%; P < 0.001). Receiver-operating characteristic curve analysis was performed and indicated the best RDW cut point was 13.16%. Furthermore, multivariate logistic regression analysis indicated that RDW level > 13.16% could be an independent risk factor for LAT/LASEC in patients with AF.

CONCLUSION

Elevated RDW level is associated with the presence of LAT/LASEC and could be with moderate predictive value for LAT/LASEC in patients with non-valvular AF.