What is the predictive value of QRS duration in patients hospitalized with worsening CHF?
Background: In outpatients, a prolonged QRS duration (greater than 120 ms) is associated with increased mortality. Its value in the inpatient setting is unclear. For patients hospitalized with CHF exacerbations, establishing the value of QRS duration may allow for tailored management.
Study design: Retrospective post hoc analysis from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST).
Setting: 4,133 patients were enrolled from North American, South American, and European sites.
Synopsis: Of 2,962 patients included in the final post hoc analysis, 1,321 (44.6%) had a prolonged QRS duration. During a median follow up of 9.9 months, the all-cause mortality rate was 18.7% for patients with a normal baseline QRS duration and 28.1% for patients with a prolonged baseline QRS.
After adjusting for confounding variables, patients with a prolonged baseline QRS had a 24% increased risk of all-cause mortality and a 28% increased risk for a composite endpoint of cardiac mortality or hospitalization for heart failure exacerbation.
The retrospective nature of the analysis represents the major limitation of this study. In addition, most of the enrolled patients were white, which limits the studies generalizability to other ethnic groups.
Bottom Line: A prolonged QRS duration for patients admitted with decompensated left ventricular heart failure is common and may be associated with increased morbidity and mortality.
Citation: Wang NC, Maggioni AP, Konstam MA, Zannad F, Drasa HB, Burnett JC, et al. Clinical implications of QRS duration in patients hospitalized with worsening heart failure and reduced left ventricular ejection fraction. JAMA. 2008;299(22):2656-2666.
For patients with out-of-hospital cardiac arrest, does the addition of vasopressin to epinephrine in a protocol for ACLS improve outcomes?
Background: The outcome for patients experiencing cardiac arrest who require vasopressors remains extremely poor. Despite disappointing data on vasopressin as an alternative treatment during cardiac arrest, a recent subgroup analysis suggested patients who received epinephrine and vasopressin together had superior clinical outcomes.
Study Design: Prospective multicenter randomized double-blind controlled trial.
Setting: 31 emergency medical service organizations in France.
Synopsis: Of the 2,894 patients, 20.7% of those receiving combination treatment (vasopressin plus epinephrine) survived to hospital admission versus 21.3% of those in the epinephrine-only group. For those same groups, 1.7% of combination and 2.3% of epinephrine-only patients survived to hospital discharge. No significant outcome differences were found in any group or subgroup analysis.
The study had lower-than-expected overall survival to hospital discharge, which may have handicapped its effort to find a true difference in treatment arms.
Bottom line: The addition of vasopressin to epinephrine in the treatment of out-of-hospital cardiac arrest does not improve outcomes.
Citation: Gueugniaud PY, David JS, Chanzy E, Hubert H, Dubien P, Mauriaucourt P, et al. Vasopressin and epinephrine vs. epinephrine alone in cardiopulmonary resuscitation. N Engl J Med. 2008;359(1):21-30.
Is oral rivaroxaban more efficacious than subcutaneous enoxaparin in preventing VTE after hip-replacement surgery?
Background: Venous thromboembolism (VTE) prophylaxis after total hip replacement (THR) is important but can be cumbersome because the most commonly used anticoagulants are either subcutaneous or require frequent monitoring. Rivaroxaban, an oral direct inhibitor of factor Xa may provide more convenient anticoagulation postoperatively. However, its efficacy and safety are unknown.
Study design: Randomized double-blind trial.
Setting: Multicenter study performed in 27 countries.
Synopsis: Patients undergoing THR surgery were randomized to oral rivaroxaban (10mg once daily without monitoring, started six to eight hours after surgery) or subcutaneous enoxaparin (40mg once daily, started 12 hours prior to surgery). After surgery, prophylaxis was administered for 35 days. The primary outcome was a composite of asymptomatic deep venous thrombosis (DVT), symptomatic DVT or pulmonary embolism (PE), or death from any cause at 36 days after surgery.