Effects of Angiotensin Receptor-Neprilysin Inhibitor in Arrhythmogenicity Following Left Atrial Appendage Closure in an Animal Model

Implications of Atrial Fibrillation for Guideline-Directed Therapy in Patients With Heart Failure: JACC State-of-the-Art Review

Atrial fibrillation (AF) and heart failure (HF) are common cardiovascular conditions that frequently coexist. Among patients with HF, more than one-half also have AF. Both are associated with significant morbidity and mortality. Moreover, the prevalence of each is increasing globally, and this trend is expected to continue owing to an aging population and increased life expectancy. Diagnosis of AF in a patient with HF is associated with greater symptom burden, more frequent hospitalizations, and a worse prognosis. Guideline-directed medical therapy (GDMT) for HF can affect the incidence of AF. Once present, AF can influence the efficacy of some components of GDMT for HF. In this review, we discuss the effect of GDMT for HF across the spectrum of ejection fraction on prevention of AF as well as the benefit of GDMT in patients with vs without AF.

Incidence of atrial and ventricular arrhythmias in obese patients with heart failure with reduced ejection fraction treated with sacubitril/valsartan

AIM

To compare clinical outcomes among patients with heart failure and reduced ejection fraction (HFrEF) according to body mass index (BMI) after initiating treatment with an angiotensin-receptor neprilysin inhibitor (ARNI).

METHODS

We gathered data from 2016 to 2020 at the University Medical Center Mannheim; 208 consecutive patients were divided into two groups according to BMI (< 30 kg/m2 ; n = 116, ≥ 30 kg/m2 ; n = 92). Clinical outcomes, including mortality rate, all-cause hospitalizations and congestion, were systematically analysed.

RESULTS

At the 12-month follow-up, the mortality rate was similar in both groups (7.9% in BMI < 30 kg/m2 vs. 5.6% in BMI ≥ 30 kg/m2 ; P = .76). All-cause hospitalization before ARNI treatment was comparable in both groups (63.8% in BMI < 30 kg/m2 vs. 57.6% in BMI ≥ 30 kg/m2 ; P = .69). After ARNI treatment, the hospitalization rate was also comparable in both groups at the 12-month follow-up (52.2% in BMI < 30 kg/m2 vs. 53.7% in BMI ≥ 30 kg/m2 ; P = .73). Obese patients experienced more congestion compared with non-obese patients at follow-up, without statistical significance (6.8% in BMI < 30 kg/m2 vs. 15.5% in BMI ≥ 30 kg/m2 ; P = .11). Median left ventricular ejection fraction (LVEF) improved in both groups, but significantly more in non-obese compared with obese patients at the 12-month follow-up (from 26% [3%-45%] [min.-max.] vs. 29% [10%-45%] [min.-max.] [P = .56] to 35.5% [15%-59%] [min.-max.] vs. 30% [13%-50%] [min.-max.] [P = .03], respectively). The incidence of atrial fibrillation (AF), non-sustained (ns) and sustained ventricular tachycardia (VT) and ventricular fibrillation (VF) was less in non-obese than in obese patients after initiation of sacubitril/valsartan at the 12-month follow-up (AF: 43.5% vs. 53.7%; P = .20; nsVT: 9.8% vs. 28.4%; P = .01; VT: 14.1% vs. 17.9%; P = .52; VF: 7.6% vs. 13.4%; P = .23).

CONCLUSIONS

The incidence of congestion in obese patients was higher compared with non-obese patients. LVEF improved significantly more in non-obese compared with obese HFrEF patients. Furthermore, AF and the ventricular tachyarrhythmia rate were revealed more in obesity compared with those without obesity at the 12-month follow-up.

Angiotensin receptor-neprilysin inhibitor delays progression from paroxysmal to persistent atrial fibrillation

Progression from paroxysmal to persistent atrial fibrillation (AF) is linked to adverse clinical outcomes. The present study sought to clarify whether angiotensin receptor-neprilysin inhibitor (ARNI) can delay AF progression. A retrospective cohort study was conducted on consecutive patients with paroxysmal AF admitted at the Second Affiliated Hospital of Nanchang University between January 2017 and January 2022. The risk of AF progression from paroxysmal to persistent was compared between paroxysmal patients treated with ARNI and those who received an angiotensin receptor blocker (ARB). Seven-day Holter monitoring was performed to identify persistent AF. Propensity-score matched analysis was performed to compare the two groups. Cox-regression was used to estimate the hazard ratio (HR) for AF progression events. A total of 1083 patients were screened, and 113 patients in the ARB group and 57 patients in the ARNI group were eligible for analysis. Before propensity-score matching, the ARNI therapy was associated with a lower risk of AF progression than the ARB therapy (HR 0.34; 95% confidence interval [CI] 0.14-0.81; P = 0.015) after a median follow-up of 705 (interquartile range [IQR] 512 to 895) days. Among 170 patients, 47 ARNI-treated patients were successfully matched to 47 ARB-treated patients. After a median follow-up of 724 (541-929) days, compared to ARB, ARNI significantly reduced the risk of AF progression (HR 0.32; 95% CI 0.12-0.88; P = 0.016). ARNI may be superior to ARB in reducing the risk of progression from paroxysmal to persistent AF.

Effect of angiotensin receptor-neprilysin inhibitor on atrial electrical instability in atrial fibrillation

Background and objective

Around 33.5 million patients suffered from atrial fibrillation (AF), causing complications and increasing mortality and disability rate. Upstream treatment for AF is getting more popular in clinical practice in recent years. The angiotensin receptor-neprilysin inhibitor (ARNI) is one of the potential treatment options. Our study aimed to investigate the effect of ARNI on atrial electrical instability and structural remodeling in AF.

Methods

Our research consisted of two parts - a retrospective real-world clinical study and an animal experiment on calmness to verify the retrospective founding. In the retrospective study, we reviewed all patients (n = 110) who had undergone the first AF ablation from 1 August 2018 to 1 March 2022. Patients with ARNI (n = 36) or angiotensin II receptor antagonist (ARB) (n = 35) treatment were enrolled. Their clinical data, ultrasound cardiogram (UCG) and Holter parameters were collected before radiofrequency catheter ablation (RFCA) as baseline and at 24-week follow-up. Univariate and multivariate logistic regression analysis were performed. In the animal experiment, we established an AF model (n = 18) on canines by rapid atrial pacing. After the successful procedure of pacing, all the 15 alive beagles were equally and randomly assigned to three groups (n = 5 each): Control group, ARB group, and ARNI group. UCG was performed before the pacing as baseline. Physiological biopsy, UCG, and electrophysiological study (EPS) were performed at 8-week.

Results

Clinical data showed that the atrial arrhythmia rate at 24-week was significantly lower in ARNI group compared to ARB group (P < 0.01), and ARNI was independently associated with a lower atrial arrhythmia rate (P < 0.05) at 24-week in multivariate regression logistic analysis. In the animal experiment, ARNI group had a higher atrial electrical stability score and a shorter AF duration in the EPS compared to Control and ARB group (P < 0.05). In the left atrium voltage mapping, ARNI group showed less low voltage and disordered zone compared to Control and ARB group. Compared to Control group, right atrium diameter (RAD), left ventricle end-diastolic volume index (LVEDVI), E/A, and E/E' were lower in ARNI group (P < 0.05) at the 8-weeks follow-up, while left atrium ejection fraction (LAEF) and left ventricle ejection fraction (LVEF) were higher (P < 0.01). Compared to ARB group, LVEF was higher in ARNI group at the 8-week follow-up (P < 0.05). ARB and ARNI group had a lower ratio of fibrotic lesions in the left atrium tissues compared to Control group (P < 0.01), but no difference was found between the ARB and the ARNI group.

Conclusion

ARNI could reduce atrial electrical instability in AF in comparison with ARB in both retrospective study and animal experiment.

Angiotensin receptor-neprilysin inhibitor therapy and recurrence of atrial fibrillation after radiofrequency catheter ablation: A propensity-matched cohort study

Background

Compared with conventional medicines, angiotensin receptor-neprilysin inhibitor (ARNI) could further improve the prognosis for multiple cardiovascular diseases, such as heart failure, hypertension, and myocardial infarction. However, the relationship between ARNI therapy and the recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation is currently unknown.

Methods

This study is a retrospective cohort study. Patients with consecutive persistent or paroxysmal AF undergoing first-time radiofrequency ablation were enrolled from February 2018 to October 2021. We compared the risk of AF recurrence in patients with catheter ablation who received ARNI with the risk of AF recurrence in those who received the angiotensin-converting enzyme inhibitor (ACEI). The propensity-score matched analysis was conducted to examine the effectiveness of ARNI. We used a Cox regression model to evaluate AF recurrence events.

Results

Among 679 eligible patients, 155 patients with ARNI treatment and 155 patients with ACEI treatment were included in the analyses. At a median follow-up of 228 (196–322) days, ARNI as compared with ACEI was associated with a lower risk of AF recurrence [adjusted hazard ratio (HR), 0.39; 95% confidence interval (CI), 0.24–0.63; p &lt; 0.001]. In addition, no interaction was found in the subgroup analysis.

Conclusion

Angiotensin receptor-neprilysin inhibitor treatment was associated with a decreased risk of AF recurrence after first-time radiofrequency catheter ablation.

Exclusion of left atrial appendage: effects beyond thromboembolic prevention

PURPOSE OF REVIEW

This review aims to summarize the nonthromboembolic prevention effects of left atrial appendage exclusion (LAAE).

RECENT FINDINGS

Left atrial appendage (LAA) secretes multiple hormones; regulates blood volume and pressure; and generates trigger activities. Exclusion of the LAA by different techniques may lead to downstream effects including changes in blood pressure and cardiac performance, improvement of outcome of atrial fibrillation (AF) ablation, and alteration of metabolism.

SUMMARY

LAAE procedures not only prevent thromboembolic events in patients with AF, but rather may bring additional benefits or side-effect to patients undergoing LAAE.

Angiotensin Receptor-Neprilysin Inhibitor (ARNI) and Cardiac Arrhythmias

The renin-angiotensin-aldosterone system (RAAS) plays a major role in cardiovascular health and disease. Short-term RAAS activation controls water and salt retention and causes vasoconstriction, which are beneficial for maintaining cardiac output in low blood pressure and early stage heart failure. However, prolonged RAAS activation is detrimental, leading to structural remodeling and cardiac dysfunction. Natriuretic peptides (NPs) are activated to counterbalance the effect of RAAS and sympathetic nervous system by facilitating water and salt excretion and causing vasodilation. Neprilysin is a major NP-degrading enzyme that degrades multiple vaso-modulatory substances. Although the inhibition of neprilysin alone is not sufficient to counterbalance RAAS activation in cardiovascular diseases (e.g., hypertension and heart failure), a combination of angiotensin receptor blocker and neprilysin inhibitor (ARNI) was highly effective in several clinical trials and may modulate the risk of atrial and ventricular arrhythmias. This review summarizes the possible link between ARNI and cardiac arrhythmias and discusses potential underlying mechanisms, providing novel insights about the therapeutic role and safety profile of ARNI in the cardiovascular system.