Comparison of High- and Low-Dose Rivaroxaban Regimens in Elderly East Asian Patients With Atrial Fibrillation.

BACKGROUND: In the Rivaroxaban Once-daily oral direct factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) trial, rivaroxaban 20 mg was the on-label dose, and the dose-reduction criterion for rivaroxaban was a creatinine clearance of < 50 mL/min. Some Asian countries are using reduced doses label according to the J-ROCKET AF trial. The aim of this study was to assess the safety and efficacy of a high-dose rivaroxaban regimen (HDRR, 20/15 mg) and low-dose rivaroxaban regimen (LDRR, 15/10 mg) among elderly East Asian patients with atrial fibrillation (AF) in real-world practice. METHODS: This study was a multicenter, prospective, non-interventional observational study designed to evaluate the efficacy and safety of rivaroxaban in AF patients > 65 years of age with or without renal impairment. RESULTS: A total of 1,093 patients (mean age, 72.8 ± 5.8 years; 686 [62.9%] men) were included in the analysis, with 493 patients allocated to the HDRR group and 598 patients allocated to the LDRR group. A total of 765 patients received 15 mg of rivaroxaban (203 in the HDRR group and 562 in the LDRR group). There were no significant differences in the incidence rates of major bleeding (adjusted hazard ratio [HR], 0.64; 95% confidential interval [CI], 0.21-1.93), stroke (adjusted HR, 3.21; 95% CI, 0.54-19.03), and composite outcomes (adjusted HR, 1.13; 95% CI, 0.47-2.69) between the HDRR and LDRR groups. CONCLUSION: This study revealed the safety and effectiveness of either dose regimen of rivaroxaban in an Asian population for stroke prevention of AF. Considerable numbers of patients are receiving LDRR therapy in real-world practice in Asia. Both regimens were safe and effective for these patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04096547.

Long-term evaluation of sensing variability of a floating atrial dipole in a single­lead defibrillator: The mechanistic basis of long-term stability of amplified atrial electrogram.

BACKGROUND: A single­lead implantable cardioverter-defibrillator (ICD) with a floating atrial dipole has been developed to enhance the diagnostic capability of atrial arrhythmias and to facilitate adjudication of arrhythmic events without the additional effort required for atrial lead insertion. However, there have been concerns about the long-term reliability of atrial sensing. METHODS: We enrolled patients with the single-chamber ICD with atrial-sensing electrodes from 4 tertiary university hospitals in Korea. Minimal, maximal, and mean P wave amplitudes were collected at 3-6 months, 6-12 months, and 12-24 months after implantation. The difference between the minimal and maximal sensing amplitudes was calculated as an indicator of the variability of atrial sensing, while the atrial sensing stability was assessed using the mean amplitude. RESULTS: A total of 86 patients were included for analysis. The variability of atrial sensing amplitudes significantly decreased at 12-24 months compared to 3-6 months (p = 0.01), while mean atrial amplitudes were stable throughout the mean follow-up duration of 17.4 months. Nine patients (10.5%) experienced inappropriate ICD therapy mostly due to misclassification of supraventricular tachycardia. CONCLUSIONS: Under the hypothesis that sensing stability can be guaranteed as the variability decreases with time, we suggest that the concern about long-term sensing stability of a floating dipole can be abated with an ICD that has been implanted for over 2 years.

Electrophysiologic Results After Thoracoscopic Ablation for Chronic Atrial Fibrillation.

BACKGROUND: Thoracoscopic ablation for lone atrial fibrillation (AF) has evolved rapidly in the past decade. We investigated the electrophysiologic results and midterm durability of totally thoracoscopic ablation in patients with lone persistent AF. METHODS: Seventy-nine consecutive patients with paroxysmal AF (8 patients, 10.1%), persistent AF (17 patients, 21.5%), and long-standing persistent AF (54 patients, 68.3%) were prospectively enrolled. Thoracoscopic ablation consisted of a bilateral closed-chest approach to performing pulmonary isolation (a box lesion), ganglionated plexus ablation, division of the Marshall ligament, and left atrial auricle resection. An electrophysiologic study was performed 5 days after the surgical procedure in 61 patients (77%). Freedom from AF was assessed with electrocardiograms or Holter monitoring every 3 months, with a mean follow-up of 12.1 (maximum, 28) months. RESULTS: No deaths or conversion to cardiopulmonary bypass occurred. During electrophysiologic study, 28 residual pulmonary vein potentials were observed in 15 patients (19%). Out of a total of 28 gaps, 20 (71%) were located in the superior and inferior ridges of pulmonary veins. Six gaps (21%) were detected in the carina of pulmonary veins. The mitral isthmus was ablated in 2 patients (7%). Freedom from AF at 2 years was 92.6 ± 3.3%. Freedom from cardiac-related events at 2 years was 74.7 ± 6.0%. Cox regression analysis demonstrated that the predictors of atrial arrhythmias were old age, hypertension, and left atrial volume index. CONCLUSIONS: Thoracoscopic ablation followed by electrophysiologic confirmation was safe and provided excellent midterm durability in patients with AF. However, the incidence of residual potentials around the pulmonary veins was not negligible.

Paced QRS axis as a predictor of pacing-induced left ventricular dysfunction.

PURPOSE: The selection of the optimal right ventricular (RV) pacing site remains unclear. We hypothesized that a normal paced QRS axis would provide a physiological ventricular activation and lead to a better long-term outcome. METHODS: We evaluated 187 patients who underwent a permanent pacemaker implantation and were dependent on RV pacing. The pacing sites were classified as the apex and non-apex according to the chest radiography. A paced QRS axis was defined as that between -30° and 90°. Preservation of the left ventricular (LV) systolic function was defined as that with a <10 % decrease in the ejection fraction after the pacemaker implantation. RESULTS: The median follow-up period was 5.8 years (interquartile 3.9-9.0). Radiographically, the RV leads were located in the apex (n = 148, 79 %) or non-apex (n = 39, 21 %). In the electrocardiogram, normal paced and abnormal paced QRS axes were observed in 28 patients (15 %) and 159 patients (85 %), respectively. The LV ejection fraction was decreased in the patients with an abnormal paced QRS axis (-10 ± 10 %, P < 0.001), but not in those with a normal axis (0 ± 6 %, P = 0.80). The electrocardiographic determinant differentiated a preserved LV function (95 % vs. 35 %, log-rank P = 0.04). Among the patients with radiographically non-apical pacing, a normal paced QRS axis was an additional meaningful predictor of a preserved LV function after the pacemaker implantation (95 % vs. 24 %, log-rank P = 0.002). CONCLUSION: Compared with the radiographic method, a normal paced QRS axis was associated with a preserved LV function.

Comparison of effects of atorvastatin (20 mg) versus rosuvastatin (10 mg) therapy on mild coronary atherosclerotic plaques (from the ARTMAP trial).

High-dose rosuvastatin induces regression of coronary atherosclerosis, but it remains uncertain whether usual-dose statin has similar effects. We compared the effects of atorvastatin 20 mg/day versus rosuvastatin 10 mg/day on mild coronary atherosclerotic plaques (20% to 50% luminal narrowing and lesion length >10 mm) using intravascular ultrasound (IVUS). Three hundred fifty statin-naive patients with mild coronary atherosclerotic plaques were randomized to receive atorvastatin 20 mg/day or rosuvastatin 10 mg/day. IVUS examinations were performed at baseline and 6-month follow-up. Primary end point was percent change in total atheroma volume (TAV) defined as (TAV at 6 months - TAV at baseline)/(TAV at baseline) × 100. Evaluable IVUS was obtained for 271 patients (atorvastatin in 143, rosuvastatin in 128). Clinical characteristics, lipid levels, and IVUS measurements at baseline were similar between the 2 groups. At 6-month follow-up, percent change in TAV was significantly less in the atorvastatin group than in the rosuvastatin group (-3.9 ± 11.9% vs -7.4 ± 10.6%, respectively, p = 0.018). In contrast, change in percent atheroma volume was not different between the 2 groups (-0.3 ± 4.2 vs -1.1 ± 3.5, respectively, p = 0.157). Compared to baseline, TAV and TAV at the most diseased 10-mm subsegment were significantly decreased in the 2 groups (p <0.001). Changes in lipid profiles at 6-month follow-up were similar between the 2 groups. In conclusion, usual doses of atorvastatin and rosuvastatin induced significant regression of coronary atherosclerosis in statin-naive patients, with a greater decrease in favor of rosuvastatin.

Circadian and seasonal variations of ventricular tachyarrhythmias in patients with early repolarization syndrome and Brugada syndrome: analysis of patients with implantable cardioverter defibrillator.

INTRODUCTION: The circadian and seasonal patterns of ventricular tachyarrhythmia (VTA) in patients with early repolarization syndrome (ERS) have not been determined. We compared the timing of VTAs in patients with ERS and Brugada syndrome (BS). METHODS AND RESULTS: We enrolled patients with ERS (n = 14) and BS (n = 53) who underwent implantable cardioverter defibrillator (ICD) implantation. The timing of VTAs, including cardiac arrest and appropriate shocks, was determined. During follow up of 6.4 ± 3.6 years in the ERS group and 5.0 ± 3.3 years in the BS group, 5 of 14 (36%) ERS and 10 of 53 (19%) BS patients experienced appropriate shocks (P = 0.37). Cardiac arrest showed a trend of nocturnal distribution peaking from midnight to early morning (P = 0.14 in ERS, P = 0.16 in BS). Circadian distribution of appropriate shocks showed a significant nocturnal peak in patients with ERS (P < 0.0001) but a trend toward a nocturnal peak in patients with BS (P = 0.08). There were no seasonal differences in cardiac arrest in patients with ERS and BS. However, patients with ERS showed a seasonal peak in appropriate shocks from spring to summer (P < 0.0001). There was no significant seasonal peak in patients with BS. The timing of VTAs (cardiac arrest plus appropriate shock) showed significant nocturnal distributions in patients with ERS and BS (P < 0.01, respectively). A significant clustering of VTAs was noted from spring to summer (P < 0.01) in patients with ERS, but not in patients with BS (P = 0.42). CONCLUSIONS: Incidence of VTAs showed marked circadian variations with night-time peaks in patients with ERS and BS.

Thalidomide as a potent inhibitor of neointimal hyperplasia after balloon injury in rat carotid artery.

OBJECTIVE: Inflammation is one of the main pathogeneses of neointimal hyperplasia after coronary intervention. Thalidomide, because of its potent antiinflammatory and immunomodulatory properties, is being re-evaluated in several clinical fields. Therefore, we examined whether thalidomide therapy affects neointimal formation. METHODS AND RESULTS: In male Sprague-Dawley rats, 100 mg/kg of either thalidomide or sucrose (control) was administered daily from 3 days before injury to 2 weeks after conventional carotid artery denudation injury. Thalidomide administration resulted in a significant reduction of neointimal formation (neointima to media ratio 1.26+/-0.29 versus 0.35+/-0.13, P<0.001) and proliferative activity of vascular smooth muscle cells. In addition, arterial macrophage infiltration and local expressions of tumor necrosis factor alpha (TNF-alpha) and basic fibroblast growth factor (bFGF) in the injured arteries as measured by immunohistochemistry and immunoblot analysis were significantly reduced by thalidomide treatment. Serum TNF-alpha, measured by ELISA, was also significantly reduced in the thalidomide-treated animals compared with controls after injury (856+/-213 versus 449+/-68 pg/mL on day 3, P=0.001; 129+/-34 versus 63+/-18 pg/mL on day 14, P=0.001), and we observed a good positive correlation between the serum TNF-alpha levels and the severity of neointimal growth. CONCLUSIONS: We found that thalidomide, through its antiinflammatory and antiproliferative effects, significantly inhibits neointimal hyperplasia in balloon-injured rat carotid arteries. Our results suggest a potential role of thalidomide as a potent inhibitor of neointimal formation after angioplasty.