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Background Retrospective series report varied rates of bleeding and infection with external ventricular drainage (EVD). There have been no prospective studies of these risks with systematic surveillance, threshold definitions, or independent adjudication. Objective We analyzed the rate of complications in the ongoing CLEAR III trial, providing a comparison with a systematic review of complications of EVD in the literature. Methods Cases were prospectively enrolled in the CLEAR III trial after placement of EVD for obstructive intraventricular hemorrhage (IVH) and randomized to receive recombinant tissue plasminogen activator (rt-PA) or placebo. We counted any detected new hemorrhage (catheter tract hemorrhage or any other distant hemorrhage) on CT scan within 30 days from the randomization. Meta-analysis of published series of EVD placement was compiled using STATA software. Results Growing or unstable hemorrhage was reported as a cause of exclusion from the trial in 74 of 5707 cases (1.3%) screened for CLEAR III. The first 250 cases enrolled have completed adjudication of adverse events. Forty-two subjects (16.8%) experienced one or more new bleeds or expansions, and 6 of 250 subjects (2.4%) suffered symptomatic hemorrhages. Eleven cases (4.4%) had culture-proven bacterial meningitis or ventriculitis. Conclusion Risks of bleeding and infection in the ongoing CLEAR III trial are comparable to those previously reported in EVD case series. In the current study, rates of new bleeds and bacterial meningitis/ventriculitis are very low, despite multiple daily injections, blood in the ventricles, the use of thrombolysis in half the cases, and generalization to > 60 trial sites.

QT interval prolongation is associated with a risk of polymorphic ventricular tachycardia. QT interval shortens with increasing heart rate and correction for this effect is necessary for meaningful QT interval assessment. We aim to improve current methods of correcting the QT interval during atrial fibrillation (AF). Digitized Holter recordings were analyzed from patients with AF. Models of QT interval dependence on RR intervals were tested by sorting the beats into 20 bins based on corrected RR interval and assessing ST-T variability within the bins. Signal-averaging within bins was performed to determine QT/RR dependence. Data from 30 patients (29 men, 69.3±7.3 years) were evaluated. QT behavior in AF is well described by a linear function (slope ~0.19) of steady-state corrected RR interval. Corrected RR is calculated as a combination of an exponential weight function with time-constant of 2 minutes and a smaller “immediate response” component (weight ~ 0.18). This model performs significantly (p<0.0001) better than models based on instantaneous RR interval only including Bazett and Fridericia. It also outperforms models based on shorter time-constants and other previously proposed models. This model may improve detection of repolarization delay in AF. QT response to heart rate changes in AF is similar to previously published QT dynamics during atrial pacing and in sinus rhythm.

Introduction: Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. Though often felt to be self-limited, this complication has been associated with increases in both short and long-term stroke and mortality. Several studies have also shown a high rate of AF recurrence. Optimal treatment strategy is not yet defined, and the role of anticoagulation (AC) is unclear. Our objective was to determine provider attitudes toward management of this common complication. Methods: A survey consisting of 15 multiple choice questions was distributed to providers at Veterans Healthcare Administration hospitals nationwide. Results: The majority of respondents were cardiologists. Practices varied drastically with respect to AC use for patients with POAF who were discharged in normal sinus rhythm. Less variability existed for patients discharged in AF. There was no clear consensus regarding other factors to consider when deciding on AC therapy, including length of episode, or risk factors for stroke such as CHA 2 DS 2-VASc score. There was also no consensus on duration of therapy or need for post discharge cardiac monitoring. Conclusion: Our data indicate a wide variability in the management of POAF. This reflects conflicting recommendations in the guidelines, as well as a paucity of prospective treatment trials in this field. Nevertheless, a growing evidence base suggests that this complication carries potentially serious long-term morbidity and mortality, and better evidence for its management is needed. K E Y W O R D S anticoagulation, new onset atrial fibrillation, postoperative atrial fibrillation (POAF) 1 INTRODUCTION Postoperative atrial fibrillation (POAF) is a frequent complication after cardiac surgery, with an incidence between 20 and 50%. 1-2 Patients with this complication have been reported as having significantly increase risk of complications, including stroke and all-cause Abbreviations: AC, anticoagulation; DOAC, direct oral anticoagulant; POAF, postoperative atrial fibrillation. mortality. 3-6 It has also been demonstrated that POAF frequently recurs during long-term follow-up. In fact, some studies reported rates in excess of 50% recurrence over a 2-year period. 7-9 Optimal treatment for this condition is uncertain due to lack of randomized, controlled clinical trials. Anticoagulation (AC) use has shown promise in retrospective studies, but use in clinical practice is inconsistent, with some studies showing an overall usage rate lower than 25%. 10-11 Even when AC is used, there is considerable heterogeneity regarding the type, timing, and duration. 12 Furthermore, guidelines offer variable and