CHA2DS2-VASc score and left atrial volume dilatation synergistically predict incident atrial fibrillation in hypertension: an observational study from the Campania Salute Network registry

Radiomics prediction models of left atrial appendage hypercoagulability based on machine learning algorithms: an exploration about cardiac computed tomography angiography imaging

Transesophageal echocardiography (TEE) is the standard method for diagnosing left atrial appendage (LAA) hypercoagulability in patients with atrial fibrillation (AF), which means LAA thrombus/sludge, dense spontaneous echo contrast and slow LAA blood flow velocity (< 0.25 m/s). Based on machine learning algorithms, cardiac computed tomography angiography (CCTA) radiomics features were adopted to construct prediction models and explore a suitable approach for diagnosing LAA hypercoagulability and adjusting anticoagulation. This study included 652 patients with non-valvular AF. The univariate analysis were used to select meaningful clinical characteristics to predict LAA hypercoagulability. Then 3D Slicer software was adopted to extract radiomics features from CCTA imaging. The radiomics score was calculated using the least absolute shrinkage and selection operator logistic regression analysis to predict LAA hypercoagulability. We then combined clinical characteristics and radiomics scores to construct a nomogram model. Finally, we got prediction models based on machine learning algorithms and logistic regression separately. The area under the receiver operating characteristic curve of radiomics score was 0.8449 in the training set and 0.7998 in the validation set. The nomogram model had a concordance index of 0.838. The final machine-learning based prediction models had good performances (best f1 score = 0.85). Radiomics features of long maximum diameter and high uniformity of Hounsfield unit in left atrial were significant predictors of the hypercoagulable state in LAA, with better predictive efficacy than clinical characteristics. Our combined models based on machine learning were reliable for hypercoagulable state screening and anticoagulation adjustment.

The intergated approach to the management of arterial hypertension: The CampaniaSalute Network

The second half of the last century was characterized by intense research in the field of arterial hypertension and related therapies. These studies showed that the management of arterial hypertension requires a robust coordination with close integration of the "health care systems" and "health care professionals". In 1998, the health care organization named "Campania Salute Network" was set up at the University of Naples Federico II. The Campania Salute Network involves 23 outpatient hypertensive clinics distributed in different community hospitals of the Regione Campania's area, 60 randomly selected general practitioners uniformly distributed in the same area, and the Hypertension Clinic of the Federico II University in Naples (coordinating centre). Through this network, clinical data collected at each visit are shared (via text messages or emails) with peripheral units (general practitioners and community hospital outpatient hypertensive clinics). The coordinating centre works in co-operation with the peripheral units in the treatment and follow-up of all hypertensive patients (i.e. assessing hypertension mediated organ damage and associated diseases). Informations about patients are shared through on-line access to the remote web-based database. The integrated approach to the mamangement of hyperetension determined a better control of blood pressure, that was associated with a reduction of hypertension mediated organ damage and decreased incidence of fatal or non-fatal cardiovascular events. Furthermore, this innovative approach improved the adherence and the persistence to the initial pharmacologic treatment. Campania Salute Network is also a powerful tool for the clinical and translational research with more 15,000 hypertensive patients followed for more than 15 years. This database allowed, in prospetic, large scale studies, to identify the hemodimìnamic and metabolic determinants of hypertension mediated organ damage and major cardiovascular events. The experience of Campania Salute Netwiork indicates that the creation of large databases from real life experiences becomes an indispensable condition also for artificial intelligence which, in the near future, thanks to scientific knowledge, the availability of particularly advanced hardware and software, will also be able to transform the management of arterial hypertension.

Efficacy and safety of NOAC versus warfarin in AF patients with left atrial enlargement

Background

Little is known about the effects of anticoagulation in patients with atrial fibrillation (AF) and left atrial enlargement (LAE).

Methods

Data of patients with AF were retrieved from Chang Gung Research Database during 2007–2016. We excluded patients who were not using oral anticoagulants, used anticoagulants for <30 days, used ≥2 agents concomitantly or switched anticoagulants, had left atrial diameter missing from their data, were aged <65, had received valve surgeries, had mitral stenosis, or had a history of cancer. The primary outcomes were ischemic stroke (IS)/systemic embolism (SE), major bleeding, and death from any cause.

Results

We identified 40,777 patients who received a diagnosis of AF. After the exclusion criteria were applied, 6,445 patients remained, 4,922 with LAE, and they were followed up for 2.4 ±1.9 years. The mean age of the patients was 77.32 ± 0.18 in the NOAC group and 76.58 ± 6.91 in the warfarin group (p < 0.0001); 48.24% of patients in the NOAC group and 46.98% of patients in the warfarin group were men (p > 0.05). The mean CHA₂DS₂-VASc score was 3.26 ± 1.05 in the NOAC group and 3.07 ± 1.12 in the warfarin group (p < 0.0001). The mean HAS-BLED score was 3.87 ± 3.81 in the NOAC group and 3.86 ± 3.80 in the warfarin group (p > 0.05). Furthermore, the mean LA diameter was 4.75 ± 0.63 cm in the warfarin group and 4.79 ± 0.69 cm in the warfarin group (p > 0.05). Among patients with LAE, NOAC was associated with significantly reduced IS/SE events (CRR = 0.63, 95% CI = 0.52–0.77), no difference in major bleeding (CRR = 0.91, 95% CI = 0.78–1.05), and significantly reduced death from any cause (aHR = 0.65, 95% CI = 0.52–0.80) compared with warfarin.

Conclusions

In elderly patients with AF and LAE, NOAC was associated with reduced IS/SE and death from any cause compared with warfarin, whereas no difference in major bleeding was observed between these treatments.

Pharmacological Inhibition of Serine Proteases to Reduce Cardiac Inflammation and Fibrosis in Atrial Fibrillation

Systemic inflammation correlates with an increased risk of atrial fibrillation (AF) and thrombogenesis. Systemic inflammation alters vessel permeability, allowing inflammatory and immune cell migration toward target organs, including the heart. Among inflammatory cells infiltrating the atria, macrophages and mast cell have recently attracted the interest of basic researchers due to the pathogenic mechanisms triggered by their activation. This chemotactic invasion is likely implicated in short- and long-term changes in cardiac cell-to-cell communication and in triggering fibrous tissue accumulation in the atrial myocardium and electrophysiological re-arrangements of atrial cardiomyocytes, thus favoring the onset and progression of AF. Serine proteases are a large and heterogeneous class of proteases involved in several processes that are important for cardiac function and are involved in cardiac diseases, such as (i) coagulation, (ii) fibrinolysis, (iii) extracellular matrix degradation, (iv) activation of receptors (i.e., protease-activated receptors [PPARs]), and (v) modulation of the activity of endogenous signals. The recognition of serine proteases substrates and their involvement in inflammatory/profibrotic mechanisms allowed the identification of novel cardio-protective mechanisms for commonly used drugs that inhibit serine proteases. The aim of this review is to summarize knowledge on the role of inflammation and fibrosis as determinants of AF. Moreover, we will recapitulate current findings on the role of serine proteases in the pathogenesis of AF and the possible beneficial effects of drugs inhibiting serine proteases in reducing the risk of AF through decrease of cardiac inflammation and fibrosis. These drugs include thrombin and factor Xa inhibitors (used as oral anticoagulants), dipeptidyl-peptidase 4 (DPP4) inhibitors, used for type-2 diabetes, as well as novel experimental inhibitors of mast cell chymases.