Atrial fibrillation in essential hypertension: an issue of concern

Hypertension and Atrial Fibrillation: Bridging the Gap Between Mechanisms, Risk, and Therapy

Background and objectives: Atrial fibrillation (AF), the most prevalent sustained arrhythmia, poses a significant public health challenge due to its links with stroke, heart failure, and mortality. Hypertension, a primary modifiable cardiovascular risk factor, is a well-established risk factor for AF that facilitates structural and electrical changes in the atria, including dilation, fibrosis, and pressure overload. Material and Methods: we conducted a literature search regarding the shared mechanisms, risks and treatments of hypertension and atrial fibrillation. Results: The renin-angiotensin-aldosterone system plays a pivotal role in this remodelling and inflammation, increasing AF susceptibility. Uncontrolled hypertension complicates AF management, diminishing the effectiveness of mainstay treatments, including antiarrhythmic drugs, catheter ablation, and cardioversion. Effective blood pressure management, particularly with therapies targeting the renin-angiotensin-aldosterone system (RAAS), can lower the risk of new-onset AF and reduce the incidence of recurrent AF, enhancing the success of rhythm control strategies. These antihypertensive therapies mitigate myocardial hypertrophy and fibrosis and attenuate both atrial pressure strain and the inflammatory response, mitigating the substrates for AF. Conclusion: This review highlights the urgent need for integrated strategies that combine BP control, AF screening, and lifestyle modifications to minimise the burden of AF and its complications. Future research should investigate the specific mechanisms of cellular-level interactions associated with a hypertensive predisposition to AF, including systematic inflammation and the role of genetics, the impact of blood pressure variations on AF risk, and individualised treatment strategies specifically targeting the shared mechanisms, simultaneously propagating hypertension and AF.

Meta-analysis of renin angiotensin aldosterone modulators mitigating atrial fibrillation risk in hypertensive patients

INTRODUCTION

Hypertension is associated with left ventricular hypertrophy/enlargement/fibrosis and atrial ectopic rhythm, leading to an increased risk of Atrial Fibrillation (AF). We aimed to stratify the effect of Angiotensin Converting Enzyme Inhibitors (ACEi) and Angiotensin Receptor Blockers (ARB) on the risk of AF.

METHODS

PubMed, Scopus, and Google Scholar databases were screened, and cross-citation was conducted for studies reporting AF in hypertensive patients on ACEi and ARB. Of 145 studies found till May 2023, 19 were included in this study. Binary random-effects models estimated the pooled odds ratios, I2 statistics assessed heterogeneity and sensitivity analysis was assessed using the leave-one-out method.

RESULTS

153,559 hypertensive patients met the inclusion criteria. For incidental AF, ACEi and ARB showed a significant decrease in both unadjusted (OR 0.75, 95% CI [0.66-0.85], I² = 20.79%, p=0.29) and adjusted risks (OR 0.76, 95% CI [0.62-0.93], I² = 88.41%, p<0.01). In recurrent AF, the unadjusted analysis showed no significant effect (OR 0.89, 95% CI [0.55-1.42], I² = 78.44%, p<0.01), while the adjusted analysis indicated a reduced risk (OR 0.62, 95% CI [0.50-0.76], I² = 65.71%, p<0.01). Leave-one-out sensitivity analysis confirmed these results.

CONCLUSIONS

ACEi and ARB considerably decrease the risk of incidental and recurrent AF in hypertensive patients, emphasizing the importance of treating clinical hypertension with these drugs.

Vagal milieu or electrophysiologic substrate? The link between atrial fibrillation and obstructive sleep apnea

Atrial fibrillation is the most common cardiac arrhythmia with its prevalence expected to increase to 12.1 million people in the United States by 2030. Chronic underlying conditions that affect the heart and lungs predispose patients to develop atrial fibrillation. Obstructive sleep apnea is strongly associated with atrial fibrillation. Several pathophysiological mechanisms have been proposed to elucidate this relationship which includes electrophysiological substrate modification and the contribution of the autonomic nervous system. In this comprehensive review, we highlight important relationships and plausible causality between obstructive sleep apnea and atrial fibrillation which will improve our understanding in the evaluation, management, and prevention of atrial fibrillation. This is the most updated comprehensive review of the relationship between obstructive sleep apnea and atrial fibrillation.

Hypertension and Arrhythmias

Hypertension is the most common cardiovascular risk factor and underlies heart failure, coronary artery disease, stroke, and chronic kidney disease. Hypertensive heart disease can manifest as cardiac arrhythmias. Supraventricular and ventricular arrhythmias may occur in the hypertensive patients. Atrial fibrillation and hypertension contribute to an increased risk of stroke. Some antihypertensive drugs predispose to electrolyte abnormalities, which may result in atrial and ventricular arrhythmias. A multipronged strategy involving appropriate screening, aggressive lifestyle modifications, and optimal pharmacotherapy can result in improved blood pressure control and prevent the onset or delay progression of heart failure, coronary artery disease, and cardiac arrhythmias.

Addressing Multimorbidity and Polypharmacy in Individuals With Atrial Fibrillation

PURPOSE OF REVIEW

The objectives of this review were to (1) discuss how multimorbidity and polypharmacy contributes to the complexity of management among individuals with AF and (2) identify any interventions to manage polypharmacy in relation to AF.

RECENT FINDINGS

Based on the four landmark clinical trials of novel anticoagulants, the most common comorbidities with AF are hypertension, heart failure, diabetes, stroke and myocardial infarction. Polypharmacy was also found prevalent in 76.5% of patients with AF, with a median of six drugs per patient. Despite the consequences of polypharmacy in AF, there is very little evidence-based intervention designed to manage it. Hence, there is a need for further research to examine interventions to manage polypharmacy in relation to AF. Atrial fibrillation (AF) is the most common type of cardiac arrhythmia requiring treatment in adults. Due to the structural and/or electrophysiological abnormalities that occur in AF, patients are managed through the use of prophylactic anticoagulant and rate and/or rhythm control medications. However, these medications are considered high risk and can increase the chances of medication misadventure. Additionally, AF rarely occurs in isolation and is known to coexist with multiple other medical comorbidities, i.e. multimorbidity. This also increases the number of medications, i.e. polypharmacy and pill burden which results in treatment non-compliance to prescribed therapy.

Biomarkers of Inflammation, Thrombogenesis, and Collagen Turnover in Patients With Atrial Fibrillation

The purpose of this study was to determine whether there are any differences in the levels of inflammatory, thrombotic, and collagen turnover biomarkers between individuals with atrial fibrillation (AF) and healthy volunteers. Circulating plasma levels of plasminogen activator inhibitor 1 (PAI-1), CD40-ligand (CD40-L), nucleosomes (which are indicators of cell death), C-reactive protein (CRP), procollagen III N-terminal propeptide (PIIINP), procollagen III C-terminal propeptide (PIIICP), procollagen I N-terminal propeptide, tissue plasminogen activator, and von Willebrand factor were analyzed as potential biomarkers of AF. Baseline plasma was collected from patients with AF prior to ablation surgery at Loyola University Medical Center. Individuals with AF had statistically significantly increased levels of PAI-1, CD40-L, and nucleosomes, when compared to the normal population (P < .0001). Additionally, there was a statistically significant increase in the CRP (P = .01), PIIINP (P = .04), and PIIICP (P = .0008) when compared to normal individuals. From this study, it is concluded that the prothrombotic, inflammatory, and collagen turnover biomarkers PAI-1, CD40-L, nucleosomes, CRP, PIIICP, and PIIINP are elevated in AF.

Impact of GGCX polymorphisms on warfarin dose requirements in atrial fibrillation patients

Background/aim: Warfarin is a common anticoagulant with large interindividual differences and a narrow therapeutic range. The polymorphisms of gamma-glutamyl carboxylase (GGCX) are important genetic factors for warfarin dose requirements. Materials and methods: Polymerase chain reaction and direct sequencing methods were used to detect the GGCX rs699664 genotype in 215 atrial fibrillation (AF) patients with warfarin administration. The effects on warfarin dose by different genotypes were analyzed. A warfarin dosing algorithm was developed based on age, height, CYP2C9, VKORC1, and GGCX genotype. Results: In 215 AF patients, there were 104 cases of wild-type GG genotype (48.4%), 92 cases of GA genotype (42.8%), and 19 cases of AA genotype (8.8%). Patients with the GGCX rs699664 A allele (GA or AA genotypes) needed higher warfarin doses than those with the GG genotype (P < 0.05). A warfarin dosing algorithm showed that age, height, CYP2C9, VKORC1, and GGCX genotype were the best variables for estimating warfarin dose (R2 = 41.2%). Another independent cohort of 60 AF patients showed a significant linear correlation between predicted warfarin maintenance dose and actual dose (R = 0.660, P < 0.01). Conclusion: AF patients with the GA and AA genotypes in GGCX rs699664 required significantly higher warfarin doses. GGCX rs699664 is a potential predictor for the warfarin dose of AF patients.

Left atrial dimension is related to blood pressure variability in newly diagnosed untreated hypertensive patients

Variability in daily blood pressure (BPV) recorded 24-h ambulatory blood pressure monitoring (ABPM) is known to be related to left ventricular hypertrophy and an increased incidence of cardiovascular events in hypertensive patients. The aim of this study was to evaluate whether left atrium dimension, which increases early in hypertensive subjects, was related to BPV in a group of 167 drug-naive patients (100M/67F, age: 46±11yr). The patients were chosen among those consecutively sent by their general practitioners to confirm the existence of arterial hypertension and afterwards diagnosed as hypertensive (mean 24-h ABPM ⩾130/80 mm Hg). In each patient, the left atrial posteroanterior diameter index for height (LADi) and the left ventricular mass standardized for body surface area (LVMi) were measured using standardized echocardiographic methods. BPV was calculated as the weighted mean of daytime and nighttime systolic and diastolic blood pressure s.d.'s (ws.d.), according to the formula ws.d.=[(daytime s.d. × 10)+nighttime s.d. × 6)]/16. An increase in left atrial dimension (LADi>24 mm m(-1)) was present in 36 patients (21.6% of the total population). In a univariate regression, LVMi was significantly related to systolic BPV (r=0.24; P=0.02) only in men, whereas LADi was significantly related to both systolic and diastolic BPV in both genders. After adjusting for sex, age, BMI, heart rate, diastolic function and estimated glomerular filtration rate, both systolic and diastolic BPV remained significantly related to LADi (P=0.02 for both) but not to LVMi. In conclusion, this study suggests that BVP, as measured as BPws.d., is significantly and independently associated with increased LADi in newly diagnosed, treatment-naive hypertensive patients.

Obesity and atrial fibrillation: A comprehensive review of the pathophysiological mechanisms and links

Obesity is a worldwide health problem with epidemic proportions that has been associated with atrial fibrillation (AF). Even though the underlying pathophysiological mechanisms have not been completely elucidated, several experimental and clinical studies implicate obesity in the initiation and perpetuation of AF. Of note, hypertension, diabetes mellitus, metabolic syndrome, coronary artery disease, and obstructive sleep apnea, represent clinical correlates between obesity and AF. In addition, ventricular adaptation, diastolic dysfunction, and epicardial adipose tissue appear to be implicated in atrial electrical and structural remodeling, thereby promoting the arrhythmia in obese subjects. The present article provides a concise overview of the association between obesity and AF, and highlights the underlying pathophysiological mechanisms.

Relation of vitamin D deficiency and new-onset atrial fibrillation among hypertensive patients

Vitamin D deficiency is associated with various cardiovascular disorders including hypertension, coronary artery disease, and heart failure. The renin-angiotensin-aldosterone system (RAS) axis is activated in vitamin D deficiency. The RAS axis also plays a role in the pathophysiology of atrial fibrillation (AF). We aimed to investigate whether vitamin D deficiency is a risk factor for the development of new-onset AF in hypertension. A total of 227 hypertensive patients were enrolled, of whom 137 had new-onset AF; 90 patients without AF were included in the control group. The age of the patient, left atrial diameter, and vitamin D deficiency increased the probability of new-onset AF independent from confounding factors (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01-1.08; P = .03 for age; OR, 1.88; 95% CI, 1.15-3.45; P = .03 for left atrial diameter; OR, 1.68; 95% CI, 1.18-2.64; P = .03 for vitamin D deficiency). Vitamin D deficiency is associated with new-onset AF in hypertension.