Hypertension and atrial fibrillation

p300 upregulates Ikur in atrial cardiomyocytes through activating NLRP3 inflammasome in hypertension

BACKGROUND

The nucleotide-binding oligomerization domain [NOD-], leucine-rich repeats [LRR-], and Pyrin domain-containing protein 3 (NLRP3) inflammasome plays an essential role in hypertension-related atrial fibrillation (AF). p300 is involved in cardiovascular inflammation. In this study, we aimed to investigate the role of p300 in NLRP3 inflammasome activation and its subsequent impact on the Ikur current in angiotensin II (Ang II)-induced HL-1 cells and Ang II-infused mice.

METHODS

Expression levels of p300, Kv1.5, and NLRP3 in left atrial appendage (LAA) tissues from AF and sinus rhythm (SR) patients were detected by Western blot. A hypertension mouse model was established in p300 knockout (p300-KO) mice via Ang II infusion, and AF incidence was assessed by electrocardiogram (ECG) after rapid atrial pacing. In vitro, the expression level of p300 in HL-1 cells was modulated by adenoviral overexpression, curcumin (an inhibitor of p300) treatment, and smal interfering RNA (siRNA) knockdown. NLRP3 inflammasome activation was evaluated by Western blot and enzyme-linked immunosorbent assay, and electrophysiological properties of HL-1 cells were analyzed using whole-cell patch-clamp recordings. Co-immunoprecipitation assays were performed to investigate the interaction between p300 and nuclear factor kappa B (NF-κB).

RESULTS

The expression levels of p300, Kv1.5, and NLRP3 were found to be significantly higher in the LAA tissue of AF patients compared to SR patients. p300-KO decreased AF incidence in Ang II-infused mice by impairing NLRP3 inflammasome activation. p300-OE facilitated NLRP3 inflammasome activation, which subsequently increased the Ikur density and shortened the action potential duration of HL-1 cells. Both curcumin (p300 inhibitor) and p300-siRNA treatments reversed Ang II-induced atrial electrical remodeling and NLRP3 inflammasome activation. Moreover, co-immunoprecipitation showed that p300 interacts with NF-κB to promote NLRP3 inflammasome activation.

CONCLUSIONS

p300 participates in hypertension-induced AF susceptibility by interacting with NF-κB to activate the NLRP3 inflammasome, which subsequently upregulates the transmembrane current of Ikur in atrial cardiomyocytes.

Smoking timing, genetic susceptibility, and the risk of incident atrial fibrillation: a large prospective cohort study

AIMS

Although smoking is a well-known risk factor for atrial fibrillation (AF), the association of smoking timing with AF risk remains unclear. This study aimed to prospectively investigate the association of smoking timing with the risk of incident AF and test the modification effect of genetic susceptibility.

METHODS AND RESULTS

A total of 305 627 participants with detailed information for time from waking to the first cigarette were enrolled from UK Biobank database. The Cox proportional hazard model was employed to assess the relationship between smoking timing and AF risk. The weighted genetic risk score for AF was calculated. Over a median 12.2-year follow-up, 13 410 AF cases were documented. Compared with non-smokers, time from waking to the first cigarette showed gradient inverse associations with the risk of incident AF (P-trend <0.001). The adjusted hazard ratio related to smoking timing was 1.13 [95% confidence interval (CI): 0.96-1.34] for >120 min, 1.20 (95% CI: 1.01-1.42) for 61-120 min, 1.34 (95% CI: 1.19-1.51) for 30-60 min, 1.43 (95% CI: 1.26-1.63) for 5-15 min, and 1.49 (95% CI: 1.24-1.63) for <5 min, respectively. Additionally, we found that the increased risk of AF related to shorter time from waking to the first cigarette was strengthened by the genetic susceptibility to AF.

CONCLUSION

Our findings suggest gradient inverse association between time from waking to the first cigarette and risk of incident AF, and the association is strengthened by the genetic susceptibility to AF.

Evaluation of the associations of pulmonary vein vertical diameter, cardiothoracic ratio, and atrial fibrillation combined hiatal hernia

Recent studies have suggested that there may be a relationship between hiatal hernia (HH) and atrial fibrillation (AF), but the specific mechanism is unclear. The aim of this study was to explore the clinical characteristics associated with HH and AF and to identify the potential relationship between the 2 diseases. The study comprised 180 patients with HH, of which 54 had AF. Every patient had chest computed tomography to quantify the cardiothoracic ratio, HH volume, thoracic cavity volume, and diameters of the pulmonary veins. The clinical data of all patients was acquired through an electronic medical record system. Patients who experienced AF had a noticeably smaller total pulmonary vein vertical diameter (TPVVD) and a higher cardiothoracic ratio compared to those who only had HH. Logistic multivariate regression study demonstrated a significant association between TPVVD, cardiothoracic ratio, and AF in individuals with HH. This study established a correlation between TPVVD, cardiothoracic ratio, and HH in conjunction with AF. Patient with HH who had a thinner TPVVD and a bigger cardiothoracic ratio were found to have a greater likelihood of suffering from AF.

Blood pressure, brain lesions and cognitive decline in patients with atrial fibrillation

Background

The influence of atrial fibrillation (AF) and blood pressure (BP) on brain lesions and cognitive function is unclear. We aimed to investigate the association of BP with different types of brain lesions and cognitive decline in patients with AF.

Methods

Overall, 1,213 AF patients underwent standardized brain magnetic resonance imaging at baseline and after 2 years, as well as yearly neurocognitive testing. BP was measured at baseline and categorized according to guidelines. New lesions were defined as new or enlarged brain lesions after 2 years. We defined cognitive decline using three different neurocognitive tests. Logistic and Cox regression analyses were performed to examine the associations of BP with new brain lesions and cognitive decline.

Results

The mean age was 71 ± 8.4 years, 74% were male and mean BP was 135 ± 18/79 ± 12 mmHg. New ischemic lesions and white matter lesions were found in 5.4% and 18.4%, respectively. After multivariable adjustment, BP was not associated with the presence of new brain lesions after 2 years. There was no association between BP and cognitive decline over a median follow-up of 6 years when using the Montreal Cognitive Assessment or Digit Symbol Substitution Test. However, BP categories were inversely associated with cognitive decline using the Semantic Fluency Test, with the strongest association in patients with hypertension grade 1 [Hazard Ratio (95% Confidence Interval) 0.57(0.42 to 0.77)], compared to patients with optimal BP (p for linear trend: 0.025).

Conclusions

In a large cohort of AF patients, there was no association between BP and incidence of brain lesions after 2 years. Also, there was no consistent association between BP and cognitive decline over a follow-up of 6 years.

Clinical Trial Registration

https://clinicaltrials.gov/study/NCT02105844, Identifier (NCT02105844).

Development and trends in research on hypertension and atrial fibrillation: A bibliometric analysis from 2003 to 2022

BACKGROUND

This study aimed to comprehensively analyze research related to hypertension and atrial fibrillation, 2 common cardiovascular diseases with significant global public health implications, using bibliometric methods from 2003 to 2022.

METHODS

From the Web of Science Core Collection database, literature on the theme of hypertension and atrial fibrillation was retrieved. Subsequently, comprehensive bibliometric analyses were conducted across multiple dimensions utilizing software tools such as VOSviewer, Citespace, Pajek, Scimago Graphica, and ClusterProfiler. These analyses encompassed examinations of the literature according to country/region, institution, authors, journals, citation relationships, and keywords.

RESULTS

It revealed an increasing interest and shifting focus in research over the years. The analysis covered 7936 relevant publications, demonstrating a gradual rise in research activity regarding hypertension combined with atrial fibrillation over the past 2 decades, with a stable growth trend in research outcomes. Geographically, Europe and the Americas, particularly the United States, have shown the most active research in this field, while China has also gained importance in recent years. Regarding institutional contributions, internationally renowned institutions such as the University of Birmingham and the Mayo Clinic have emerged as core forces in this research direction. Additionally, Professor Lip Gregory, with his prolific research output, has stood out among numerous scholars. The American Journal of Cardiology has become a primary platform for publishing research related to hypertension and atrial fibrillation, highlighting its central role in advancing knowledge dissemination in this field. The research focus has shifted from exploring the pathophysiological mechanisms to investigating the treatment of complications and risk factors associated with hypertension and atrial fibrillation. Future research will focus on in-depth exploration of genetic and molecular mechanisms, causal relationship exploration through Mendelian randomization studies, and the application of machine learning techniques in prediction and treatment, aiming to promote the development of precision medicine for cardiovascular diseases.

CONCLUSION

In conclusion, this study provides a comprehensive overview of the developmental trajectory of research on hypertension and atrial fibrillation, presenting novel insights into trends and future research directions, thus offering information support and guidance for research in this crucial field of cardiovascular medicine.

Exploring the causal relationships and mediating factors between depression, anxiety, panic, and atrial fibrillation: A multivariable Mendelian randomization study

BACKGROUND

Atrial fibrillation is a significant cardiovascular disease, and the increased risk of its occurrence may be influenced by mental disorders. Currently, the causal relationship between them remains controversial. Our aim is to ascertain the relationship between atrial fibrillation and mental disorders including depression, anxiety, and panic, as well as the risk factors mediating this relationship, through the judgment of genetic susceptibility.

METHODS

We utilized the summarized statistics from nine large-scale genome-wide association studies (in European populations), including depression (PGC, N = 807,553), anxiety (FinnGen, N = 429,209), panic (PGC, N = 230,878), diabetes (UK Biobank, N = 655,666), smoking (IEU, 607,291), hypertension (UK biobank, N = 463,010), obstructive sleep apnea (IEU, N = 476,853), obesity (UK biobank, N = 463,010), and AF (IEU, N = 1,030,836). By applying bidirectional two-sample Mendelian randomization and multivariable Mendelian randomization to depression, anxiety, panic, and AF, we analyzed their causal relationships and the independent influence of specific risk factors. Furthermore, a two-step MR approach was used to assess the mediating effects of diabetes, smoking, hypertension, obstructive sleep apnea, and obesity.

RESULTS

Results from the Two-Sample Mendelian Randomization Inverse Variance Weighted Random Effects Model show: the occurrence of genetically predicted depression is related to an increased risk of atrial fibrillation (AF) (OR: 1.073; [95 % CI: 1.005-1.146] P < 0.05), and panic is more significantly associated than depression (OR: 1.017; [95 % CI: 1.008-1.027] P < 0.001), while anxiety has no causal relationship with the occurrence of AF (OR: 1.023; [95 % CI: 0.960-1.092], P > 0.05), and AF is not significantly related to the occurrence of depression, anxiety, or panic (P > 0.05). After correcting for the other two risk factors using multivariable Mendelian randomization, depression remains significantly related to the occurrence of AF (β: 0.075; 95 % CI: [0.006, 0.144], P < 0.05), while panic and anxiety are not related to the occurrence of AF. Among them, the risk factors for AF occurrence, hypertension and obesity, are mediators between depression and AF, with mediation proportions of 74.9 % and 14.3 %, respectively. The mediating effects of diabetes, smoking, and obstructive sleep apnea were found to be not statistically significant. The above results are robust after sensitivity analysis.

CONCLUSION

Our results identified that the genetic susceptibility to depression is an independent risk factor for the occurrence of AF, and that hypertension and obesity can mediate this process. Panic also poses some risk to the onset of AF. This demonstrates that controlling hypertension and obesity for emotional management is of great importance in preventing the occurrence of AF.

Management and Anticoagulation Treatment of Non-Valvular Atrial Fibrillation in Elderly Patients: The Dali Study

Background

Non-valvular atrial fibrillation (NVAF) is associated with increased stroke in elderly populations, yet anticoagulant therapy is underutilized. We analyzed clinical characteristics and anticoagulation treatment rates of elderly NVAF patients hospitalized in Dali, China, to identify potential contributing factors.

Methods

We collected data for 155 elderly patients with NVAF aged ≥60 years, from July 01, 2020, to December 31, 2021. We analyzed the awareness rate, clinical characteristics, and anticoagulant treatment rate of atrial fibrillation (AF), and identified factors influencing treatment. Patients were followed up one year after discharge to assess vital status, cardiovascular events, and anticoagulation therapy status.

Results

Among 155 patients, 52.26% were female, and the average age was 75.77 years. The awareness rate of AF was 47.74% at admission, and only 21.94% received anticoagulant therapy. After discharge, the rate of anticoagulant therapy significantly increased to 70.97%, and 89.09% used new oral anticoagulants. Thromboembolic history and persistent AF predicted anticoagulant therapy at discharge, while male gender, previous bleeding history, and antiplatelet therapy predicted non-anticoagulant therapy. Out of 133 patients who completed a one-year follow-up, 23.31% died, 3.01% had strokes, and 3.01% experienced bleeding. Anticoagulant therapy decreased to 51.96% during the follow-up year.

Conclusion

Our findings highlight the low awareness rate and anticoagulant treatment rate, and high mortality among elderly NVAF patients in Dali. The development of comprehensive intervention strategies is critical to standardize AF management and improve prognosis.

Atrial Fibrillation Detection and Management in Hypertension

Hypertension is prevalent in >70% of atrial fibrillation patients. In turn, hypertensive patients have up to 73% greater likelihood of atrial fibrillation. Current guidelines recommend that a systematic atrial fibrillation screening may be justified in all patients aged ≥65 years with at least 1 cardiovascular disease, including hypertension. Although most blood pressure monitors include algorithms to detect atrial fibrillation with a high sensitivity of 96 [92-98]% and specificity of 94 [91-96]%, an electrocardiography confirmation is necessary to establish a diagnosis of atrial fibrillation. Early detection and diagnosis of atrial fibrillation is important to allow initiation of atrial fibrillation management. In the Early Treatment of Atrial Fibrillation for Stroke Prevention Trial (EAST-AFNET 4), hypertension was present in 88% of participants, and early rhythm control therapy lowered the risk of adverse cardiovascular outcomes in patients with early atrial fibrillation aged >75 or with CHA₂DS₂-VASc score ≥2 (Congestive heart failure, Hypertension, Age ≥75 (doubled), Diabetes, Stroke (doubled), Vascular disease, Age 65-74, Sex category [female]) and cardiovascular condition. Strategies for early atrial fibrillation detection should always be linked to a comprehensive atrial fibrillation work-up infrastructure organized within an integrated ABC pathway (Anticoagulation/Avoid stroke; Better symptom control; Cardiovascular and Comorbidity optimization). For secondary prophylaxis, blood pressure control should be embedded in a combined risk factor management program. In hypertensive patients where no atrial fibrillation is detected, intensive blood pressure lowering therapy for primary prophylaxis should be initiated to reduce the risk of developing atrial fibrillation and other cardiovascular complications in the future. The aim of the article is to review the current literature on atrial fibrillation detection and management in hypertensive patients.