The CHADS2 Score to Predict Stroke Risk in the Absence of Atrial Fibrillation in Hypertensive Patients Aged 65 Years or Older

Activated Factor X Signaling Pathway via Protease-Activated Receptor 2 Is a Novel Therapeutic Target for Preventing Atrial Fibrillation

BACKGROUND

Activated factor X (FXa), which contributes to chronic inflammation via protease-activated receptor 2 (PAR2), might play an important role in atrial fibrillation (AF) arrhythmogenesis. This study aimed to assess whether PAR2 signaling contributes to AF arrhythmogenesis and whether rivaroxaban ameliorates atrial inflammation and prevents AF.Methods and Results:In Study 1, PAR2 deficient (PAR2-/-) and wild-type mice were infused with angiotensin II (Ang II) or a vehicle via an osmotic minipump for 2 weeks. In Study 2, spontaneously hypertensive rats (SHRs) were treated with rivaroxaban, warfarin, or vehicle for 2 weeks after 8 h of right atrial rapid pacing. The AF inducibility and atrial remodeling in both studies were examined. Ang II-treated PAR2-/- mice had a lower incidence of AF and less mRNA expression of collagen1 and collagen3 in the atrium compared to wild-type mice treated with Ang II. Rivaroxaban significantly reduced AF inducibility compared with warfarin or vehicle. In SHRs treated with a vehicle, rapid atrial pacing promoted gene expression of inflammatory and fibrosis-related biomarkers in the atrium. Rivaroxaban, but not warfarin, significantly reduced expression levels of these genes.

CONCLUSIONS

The FXa-PAR2 signaling pathway might contribute to AF arrhythmogenesis associated with atrial inflammation. A direct FXa inhibitor, rivaroxaban, could prevent atrial inflammation and reduce AF inducibility, probably by inhibiting the pro-inflammatory activation.

Low Diastolic Blood Pressure is Not Related to Risk of First Episode of Stroke in a High-Risk Population: A Secondary Analysis of SPRINT

Background

Hypertension is the most prevalent and leading risk factor for stroke. SPRINT (The Systolic Blood Pressure Intervention Trial) assessed the effects on cardiovascular event risk of intensive compared with standard systolic blood pressure reduction. In this secondary analysis of SPRINT data, we investigated how low on‐treatment diastolic blood pressure (DBP) influenced risk for stroke events.

Methods and Results

For this analysis, we used SPRINT_POP (Primary Outcome Paper) Research Materials from the National Heart, Lung and Blood Institute (NHLBI) Biologic Specimen and Data Repository Information Coordinating Center. Data for 8944 SPRINT participants were analyzed from the period after target blood pressure was achieved until the end of the trial. Overall, there were 110 stroke events, including 49 from the intensive‐treatment arm and 61 in the standard‐treatment group. In participants with DBP <70 mm Hg, stroke risk was higher than with DBP ≥70 mm Hg (hazard ratio, 1.467; 95% CI 1.009–2.133; P=0.0445). Univariable Cox proportional hazard risk analysis showed that in the whole group, age and cardiovascular and chronic renal diseases were stroke risk factors. These risk factors were related to lower DBP and higher pulse pressure, however, not to study arm. Multivariable Cox proportional hazard analysis revealed that only age, history of cardiovascular disease, current smoking status and on‐treatment systolic blood pressure were significantly related to stroke risk.

Conclusions

Low on‐treatment DBP is not related to the risk for the first stroke, in contrast to older age, the history of cardiovascular disease, current smoking status, and on‐treatment systolic blood pressure.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062.

Association Between CHADS2 Score and the Development of Interatrial Block

Interatrial block (IAB) is associated with a multitude of medical conditions. The aim of this retrospective study was to investigate whether CHADS₂ (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke) score is positively associated with the development of IAB. A total of 1072 patients (men, 555; women, 517; mean age, 61 ± 14 years) were included in the study. P-wave duration was measured manually using a caliper. IAB was defined as a P-wave duration of ≥ 120 ms on a 12-lead electrocardiogram. CHADS₂ scores were calculated retrospectively. Among the 1072 patients, the prevalence of IAB was 36.1% (387/1072). In multivariate analysis, increased CHADS₂ score (odds ratio [OR], 1.810; 95% confidence interval [CI], 1.577-2.077; P < 0.001), coronary artery disease (OR, 1.536; 95% CI, 1.065-2.216; P = 0.022), and increased left atrial diameter (OR, 1.039; 95% CI, 1.008-1.071; P = 0.013) were independently associated with IAB. The percentages of patients with IAB among those with a CHADS₂ score of 0, 1, 2, 3, 4, 5, and 6 were 20.6%, 33.0%, 45.0%, 55.9%, 61.9%, 77.8%, and 100%, respectively (P < 0.001). There was a greater percentage of patients with a CHADS₂ score of ≥ 2 with IAB compared with a CHADS₂ score of < 2 (26.5% vsrsus 52.0%; P < 0.001). In receiver operating curve (ROC) analysis, CHADS₂ score (area under the curve, 0.670; 95% CI, 0.636-0.704; P < 0.001) was predictive of IAB. In conclusion, CHADS₂ score was significantly associated with the development of IAB in this study population.

Risk Stratification Using the CHA2DS2-VASc Score in Takotsubo Syndrome: Data From the Takotsubo Italian Network

Background

The CHA₂DS₂‐VASc score predicts stroke in patients with atrial fibrillation and has been reported to have a prognostic role even in acute coronary syndrome patients. The Takotsubo syndrome is a condition that mimics acute coronary syndrome and may present several complications including stroke. We sought to assess the ability of CHA₂DS₂‐VASc score to predict adverse events in Takotsubo syndrome patients.

Methods and Results

Overall, 371 Takotsubo syndrome patients were enrolled in a prospective registry. Patients were divided into 3 groups according to the CHA₂DS₂‐VASc score: Group A (≤1), B (2–3), and C (≥4). The median CHA₂DS₂‐VASc score was 3 (interquartile range: 2–4). Overall, 9%, 42%, and 49% were included in Group A, B, and C, respectively. Follow‐up length was 26±20 months. The mortality rate was 6%, 7%, and 17% in Group A, B, and C, respectively (P=0.011). The stroke rate was 3% and not different among the 3 groups. Estimated major adverse cardiac and cerebrovascular events (the composite of death, myocardial infarction, and stroke) rates in the 3 groups were 6%, 9%, and 17% in Group A, B, and C, respectively (P=0.033). The CHA₂DS₂‐VASc score resulted as a predictor of major adverse cardiac and cerebrovascular events (odds ratio 2.1, 95% confidence interval, 1.2–3.6; P=0.01) and all‐cause mortality (odds ratio 1.5, 95% confidence interval, 1.2–1.9; P=0.001).

Conclusions

In Takotsubo syndrome, the CHA₂DS₂‐VASc score allows prediction of cardiovascular events and mortality at long‐term follow‐up.

CHADS2 and CHA2DS2-VASc Scores Predict the Risk of Ischemic Stroke Outcome in Patients with Interatrial Block without Atrial Fibrillation

Aim: To evaluate the role of CHADS₂ and CHA₂DS₂-VASc scores in predicting the risk of ischemic stroke or transient ischemic attack (TIA) outcomes in patients with interatrial block (IAB) without a history of atrial fibrillation (AF).

Methods: A retrospective study was conducted, including 1,046 non-anticoagulated inpatients (612 males, 434 females; mean age: 63 ± 10 years) with IAB and without AF. IAB was defined as P-wave duration > 120 ms using a 12-lead electrocardiogram. CHADS₂ and CHA₂DS₂-VASc scores were retrospectively calculated. The primary outcomes evaluated were ischemic stroke or TIA.

Results: During the mean follow-up period of 4.9 ± 0.7 years, 55 (5.3%) patients had an ischemic stroke or TIA. Receiver operating characteristic (ROC) curve analysis showed that the CHADS₂ score [area under the curve (AUC), 0.638; 95% confidence interval (CI), 0.562–0.715; P = 0.001] and the CHA₂DS₂-VASc score (AUC, 0.671; 95% CI, 0.599–0.744; P <0.001) were predictive of ischemic strokes or TIA. Cut-off point analysis showed that a CHADS₂ score ≥ 3 (sensitivity = 0.455 and specificity = 0.747) and a CHA₂DS₂-VASc score ≥ 4 (sensitivity = 0.564 and specificity = 0.700) provided the highest predictive value for ischemic stroke or TIA. The multivariate Cox regression analysis showed that CHADS₂ [hazard ratio (HR), 1.442; 95% CI, 1.171–1.774; P = 0.001] and CHA₂DS₂-VASc (HR, 1.420; 95% CI, 1.203–1.677; P <0.001) scores were independently associated with ischemic stroke or TIA following adjustment for smoking, left atrial diameter, antiplatelet agents, angiotensin inhibitors, and statins.

Conclusions: CHADS₂ and CHA₂DS₂-VASc scores may be predictors of risk of ischemic stroke or TIA in patients with IAB without AF.