Evaluation of an adaptive, rule-based dosing algorithm to maintain therapeutic anticoagulation during atrial fibrillation ablation.

Background: Cerebral thromboembolism during atrial fibrillation (AF) ablation is an infrequent (0.17%) complication in part owing to strict adherence to intraprocedural anticoagulation. Failure to maintain therapeutic anticoagulation can lead to an increase in events, including silent cerebral ischemia. Objective: To evaluate a computerized, clinical decision support system (CDSS) to dose intraprocedural anticoagulation and determine if it leads to improved intraprocedural anticoagulation outcomes during AF ablation. Methods: The Digital Intern dosing algorithm is an adaptive, rule-based CDSS for heparin dosing. The initial dose is calculated from the patient's weight, baseline activated clotting time (ACT), and outpatient anticoagulant. Subsequent recommendations adapt based on individual patient ACT changes. Outcomes from 50 cases prior to algorithm introduction were compared to 139 cases using the algorithm. Results: Procedures using the dosing algorithm reached goal ACT (over 300 seconds) faster (17.6 ± 11.1 minutes vs 33.3 ± 23.6 minutes pre-algorithm, P < .001). ACTs fell below goal while in the LA (odds ratio 0.20 [0.10-0.39], P < .001) and rose above 400 seconds less frequently (odds ratio 0.21 [0.07-0.59], P = .003). System Usability Scale scores were excellent (96 ± 5, n = 7, score >80.3 excellent). Preprocedure anticoagulant, weight, baseline ACT, age, sex, and renal function were potential predictors of heparin dose to achieve ACT >300 seconds and final infusion rate. Conclusion: A heparin dosing CDSS based on rules and adaptation to individual patient response improved maintenance of therapeutic ACT during AF ablation and was rated highly by nurses for usability.

Usefulness of Focused Screening Echocardiography for Collegiate Athletes.

Sudden cardiac death in a young healthy athlete is a rare but catastrophic event. The American Heart Association preparticipation screening guidelines recommend a focused history and physical without routine imaging or electrocardiogram screening. We hypothesized that a focused echocardiogram can identify structural abnormalities that may lead to sudden cardiac death in athletes, which might otherwise go undetected by history and physical. We retrospectively reviewed the charts of all incoming collegiate athletes at a single university from 2005 to 2013, all of whom had undergone a focused, 5-minute echocardiogram along with a guideline-based preparticipation history and physical (PPS H&P). Abnormal findings prompted further testing or referral. We report the prevalence of abnormal findings and the relation between an abnormal PPS H&P and screening echocardiogram. A total of 2,898 athletes were screened and 159 (5%) had findings. Forty athletes underwent further testing and evaluation. Of these athletes, 3 had newly diagnosed abnormalities that warranted restriction of participation: 1 apical-variant hypertrophic cardiomyopathy, 1 large bidirectional atrial septal defect with right ventricular dysfunction, and 1 dilated ascending aorta. Two of these athletes had a normal PPS H&P. Conversely, of the 661 athletes with an abnormal PPS H&P, only 1 (0.15%) had an abnormal screening echocardiogram. In conclusion, although the overall number was low, the 5-minute screening echocardiogram detected athletes at risk for sudden cardiac death not discovered on PPS H&P.