A randomized clinical trial to evaluate the efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valve and atrial fibrillation or flutter: rationale and design of the RIVER trial

Background The efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valves and atrial fibrillation or flutter remain uncertain. Design RIVER was an academic-led, multicenter, open-label, randomized, non-inferiority trial with blinded outcome adjudication that enrolled 1005 patients from 49 sites in Brazil. Patients with a bioprosthetic mitral valve and atrial fibrillation or flutter were randomly assigned (1:1) to rivaroxaban 20 mg once daily (15 mg in those with creatinine clearance <50 mL/min) or dose-adjusted warfarin (target international normalized ratio 2.0-30.); the follow-up period was 12 months. The primary outcome was a composite of all-cause mortality, stroke, transient ischemic attack, major bleeding, valve thrombosis, systemic embolism, or hospitalization for heart failure. Secondary outcomes included individual components of the primary composite outcome, bleeding events, and venous thromboembolism. Summary RIVER represents the largest trial specifically designed to assess the efficacy and safety of a direct oral anticoagulant in patients with bioprosthetic mitral valves and atrial fibrillation or flutter. The results of this trial can inform clinical practice and international guidelines.

A randomized clinical trial to evaluate the efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valve and atrial fibrillation or flutter: Rationale and design of the RIVER trial.

The efficacy and safety of rivaroxaban in patients with bioprosthetic mitral valves and atrial fibrillation or flutter remain uncertain. DESIGN: RIVER was an academic-led, multicenter, open-label, randomized, non-inferiority trial with blinded outcome adjudication that enrolled 1005 patients from 49 sites in Brazil. Patients with a bioprosthetic mitral valve and atrial fibrillation or flutter were randomly assigned (1:1) to rivaroxaban 20 mg once daily (15 mg in those with creatinine clearance <50 mL/min) or dose-adjusted warfarin (target international normalized ratio 2.0-30.); the follow-up period was 12 months. The primary outcome was a composite of all-cause mortality, stroke, transient ischemic attack, major bleeding, valve thrombosis, systemic embolism, or hospitalization for heart failure. Secondary outcomes included individual components of the primary composite outcome, bleeding events, and venous thromboembolism. SUMMARY: RIVER represents the largest trial specifically designed to assess the efficacy and safety of a direct oral anticoagulant in patients with bioprosthetic mitral valves and atrial fibrillation or flutter. The results of this trial can inform clinical practice and international guidelines.

Incidence and factors associated with pericardial effusion after cardiac valve surgery

Introduction: Pericardial effusion (PE) is a postoperative complication of cardiac valve surgery, related to early hospital readmissions and death. We aimed to describe its incidence and to identify predictive factors of moderate-to-severe PE in a contemporary cohort. Methods: We retrospectively reviewed medical records of all consecutive patients submitted to cardiac valve surgery in a tertiary teaching hospital from January 2012 to July 2014, where echocardiography was routinely performed before patient discharge. Moderate-to-severe PE was defined as ≥ 10 mm of thickness, or signs of cardiac tamponade on echocardiography. Additional clinical and perioperative data were extracted from medical records using a standardized protocol. Results: Of 353 patients, 335 underwent a predischarge echocardiography. From these, 27 patients (8%; mean age: 62 years; standard deviation 12 years; 70% male) had moderate-to-severe PE. These patients had a higher prevalence of previous stroke (22% vs. 8%; p = 0.009) and oral anticoagulation (international normalized ratio > 2) prior to the surgery (11 vs. 2%; P = 0.002). In patients with moderate-to-severe PE, surgeries had longer ischemia (p < 0.001) and cardiopulmonary bypass (p < 0.001) times, and the prevalence of postoperative atrial fibrillation was higher (56% vs. 32%; p = 0.011) than in patients with absent or small PE. Hospital mortality was also higher (15% vs. 3%; p = 0.002) in patients with moderate-to-severe PE. Conclusions: Eight percent of patients submitted to cardiac valve surgery developed moderate-to-severe PE. Moreover, PE was associated with pre- and post-surgery conditions likely related to the coagulation state, though a cause-effect relationship could not be inferred. Noteworthy, this condition was associated with higher in-hospital morbidity and mortality(AU)