Our data suggest that forearm endothelial dysfunction is a marker of future cardiovascular events in patients with essential hypertension.

Endothelial dysfunction has been reported in obese subjects, but its mechanism has not been elucidated. We have therefore investigated 1) the possible relationship among BMI, waist-to-hip ratio (WHR), and endothelium-dependent vasodilation and 2) whether oxidative stress participates in endothelial dysfunction. We recruited 76 healthy subjects (50 men and 26 women aged 21-45 years) and measured their BMI (kg/m 2 ), WHR, and insulin resistance (IR) estimated by the homeostasis model assessment (HOMA). Endothelium-dependent and -independent vasodilation were assessed by increasing doses of acetylcholine (ACh) (7.5, 15, and 30 µg · ml -1 · min -1) and sodium nitroprusside (SNP) (0.8, 1.6, and 3.2 µg · ml -1 · min 19.8 ± 2.8, 10.8 ± 2.7, and 6.5 ± 1.8 ml · 100 ml -1 tissue · min -1 (P < 0.0001) for groups A, B, and C, respectively. SNP caused comparable increments in FBF in all groups. Regression analysis revealed a significant negative correlation between BMI (r = -0.676, P < 0.0001), WHR (r = -0.631, P < 0.0001), fasting insulin (r = -0.695, P < 0.0001), HOMA-IR (r = -0.633, P < 0.0001), and percent peak increase in FBF during ACh infusion. In obese subjects, both vitamin C and indomethacin increased the impaired vasodilating response to ACh, whereas the SNP effect was unchanged. In conclusion, in obese subjects, ACh-stimulated vasodilation is blunted, and the increase in FBF is inversely related to BMI, WHR, fasting insulin, and HOMA-IR. The effects of both vitamin C and indomethacin on impaired ACh-stimulated vasodilation support the hypothesis that oxidative stress contributes to endothelial dysfunction in human obesity. O bese subjects are at high risk for developing diabetes, dyslipidemia, hypertension, and cardiovascular diseases, which lead to an increased risk of mortality (1-3). Moreover, it has been demonstrated that obesity is associated with hyperinsulinemia, an independent predictor for coronary artery disease (4). In fact, hyperinsulinemia is linked to insulin resistance (IR) and potentially to atherogenic abnormalities.The normal endothelium plays a key role in the regulation of vascular tone and in preventing the progression of atherosclerosis through the production and release of both contracting and relaxing factors (5). Nitric oxide (NO) represents the major endogenous relaxing factor (6-9), and its production is stimulated by physical stimuli (e.g., shear stress) (9) and by several agonists (e.g., acetylcholine [ACh], bradykinin, substance P, and serotonin) (8). The activation of guanylate cyclase and the subsequent accumulation of cGMP are the main mechanisms of NO-induced vasodilation. In contrast, sodium nitroprusside (SNP) is an endothelium-independent vasodilator capable of inducing vasodilation by providing an inorganic source of NO (10). Major risk factors for atherosclerotic vascular diseases (e.g., hypertension, smoking, diabetes, and hypercholesterolemia) have been associated with endothelial dysfunction due to increased oxidative stress (11-16). Recent reports have also indicated tha...

Micra Transcatheter Pacing System Post-Approval Registry ClinicalTrials.gov identifier: NCT02536118; Micra Transcatheter Pacing Study ClinicalTrials.gov identifier: NCT02004873.

Performance of the Micra transcatheter pacemaker in a real-world setting demonstrates a high rate (99.6%) of implant success and low rate (1.51%) of major complications through 30 days post implant. In particular, the rates of pericardial effusion, device dislodgement, and infection were low, reinforcing the positive results seen in the investigational study.

In patients undergoing 'Ablate and Pace' therapy for severely symptomatic permanent atrial fibrillation, CRT is superior to RV apical pacing in reducing the clinical manifestations of HF. (ClinicalTrials.gov number: NCT00111527).

Accelerometer-based atrial sensing is feasible and significantly improves AVS in patients with AV block and a single-chamber leadless pacemaker implanted in the right ventricle.

Aims Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). Methods and results A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) &gt;30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P &lt; 0.001). Conclusions Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.

In this large cohort of new ICD implants, event rates were similar and extremely low in both groups. These data indicate a limited clinical relevance for DT testing, thus supporting a strategy of omitting DT during an ICD implant. (Safety of Two Strategies of ICD Management at Implantation [SAFE-ICD]; NCT00661037).