Citations

Background Hyper‐ and hypokalemia are clinically silent, common in patients with renal or cardiac disease, and are life threatening. A noninvasive, unobtrusive, blood‐free method for tracking potassium would be an important clinical advance. Methods and Results Two groups of hemodialysis patients (development group, n=26; validation group, n=19) underwent high‐resolution digital ECG recordings and had 2 to 3 blood tests during dialysis. Using advanced signal processing, we developed a personalized regression model for each patient to noninvasively calculate potassium values during the second and third dialysis sessions using only the processed single‐channel ECG . In addition, by analyzing the entire development group's first‐visit data, we created a global model for all patients that was validated against subsequent sessions in the development group and in a separate validation group. This global model sought to predict potassium, based on the T wave characteristics, with no blood tests required. For the personalized model, we successfully calculated potassium values with an absolute error of 0.36±0.34 mmol/L (or 10% of the measured blood potassium). For the global model, potassium prediction was also accurate, with an absolute error of 0.44±0.47 mmol/L for the training group (or 11% of the measured blood potassium) and 0.5±0.42 for the validation set (or 12% of the measured blood potassium). Conclusions The signal‐processed ECG derived from a single lead can be used to calculate potassium values with clinically meaningful resolution using a strategy that requires no blood tests. This enables a cost‐effective, noninvasive, unobtrusive strategy for potassium assessment that can be used during remote monitoring.

Driveline infections (DLI) are a cause of morbidity after continuous-flow left ventricular assist device (CF-LVAD) implantation. Because driveline trauma contributes to DLI, we assessed whether intraoperative placement of a temporary external anchoring suture (EAS) influenced DLI rate. We analyzed 161 consecutive patients with CF-LVAD (HMII 82; HW 79) implantation. Two groups were defined: placement of EAS (n = 85) or No EAS (n = 76). For NO EAS patients, the driveline was permanently anchored internally to the rectus fascia. Cox proportional analysis was performed to assess the effect of EAS on time to first confirmed DLI. Baseline characteristics were comparable between groups (all p = 0.3). Mean follow-up time was 0.93 years. A total of 18 (11.1%) patients developed confirmed culture positive DLI, with “first infection” rate of 0.13 events/year. Mean time to confirmed DLI was 0.69 years. Driveline infection was less likely (hazard ratio [HR] = 0.28, 0.95 confidence interval [CI] = 0.06–1.25, p = 0.056) to occur in NO EAS (2/18) then in EAS (16/18). Confirmed DLI was comparable between device types (p = 0.3). Multivariable regression adjusted for age, BMI, blood product use, device type, and diabetes showed equivocal effect of EAS (HR = 0.33, 0.95 CI = 0.07–1.54, p = 0.12). Patients with a temporary EAS may have an increased risk of confirmed DLI after device implantation.

ABSTRACTChronic pain is an important public health problem that negatively impacts the quality of life of affected individuals and exacts enormous socioeconomic costs. Chronic pain is often accompanied by comorbid emotional disorders including anxiety, depression, and possibly anhedonia. The neural circuits underlying the intersection of pain and pleasure are not well understood. We summarize recent human and animal investigations and demonstrate that aversive aspects of pain are encoded in brain regions overlapping with areas processing reward and motivation. We highlight findings revealing anatomical and functional alterations of reward/motivation circuits in chronic pain. Finally, we review supporting evidence for the concept that pain relief is rewarding and activates brain reward/motivation circuits. Adaptations in brain reward circuits may be fundamental to the pathology of chronic pain. Knowledge of brain reward processing in the context of pain could lead to the development of new therapeutics for the treatment of emotional aspects of pain and comorbid conditions. J. Comp. Neurol. 524:1646–1652, 2016. © 2016 Wiley Periodicals, Inc.

Background: American football and rugby players are at substantial risk of injury because of the full-contact nature of these sports. Methodological differences between previous epidemiological studies hamper an accurate comparison of injury rates between American football and rugby. Purpose: To directly compare injury rates in American collegiate football and rugby, specified by location, type, mechanism, and severity of injury, as reported by licensed medical professionals. Study Design: Cohort study; Level of evidence, 2. Methods: Licensed medical professionals (athletic trainer or physician) associated with the football and rugby teams of a National Collegiate Athletic Association Division I university reported attendance and injury details over 3 autumn seasons. Injuries were categorized by the location, type, mechanism, and severity of injury, and the injury rate was calculated per 1000 athlete-exposures (AEs). Injury rate ratios (IRRs) were calculated to compare overall, game, and practice injury rates within and between sports. Results: The overall injury rate was 4.9/1000 AEs in football versus 15.2/1000 AEs in rugby: IRR = 3.1 (95% CI, 2.3-4.2). Game injury rates were higher than practice injury rates: IRR = 6.5 (95% CI, 4.5-9.3) in football and IRR = 5.1 (95% CI, 3.0-8.6) in rugby. Injury rates for the shoulder, wrist/hand, and lower leg and for sprains, fractures, and contusions in rugby were >4 times as high as those in football (all P ≤ 0.006). Concussion rates were 1.0/1000 AEs in football versus 2.5/1000 AEs in rugby. Most injuries occurred via direct player contact, especially during games. The rate of season-ending injuries (>3 months of time loss) was 0.8/1000 AEs in football versus 1.0/1000 AEs in rugby: IRR = 1.3 (95% CI, 0.4-3.4). Conclusion: Overall injury rates were substantially higher in collegiate rugby compared with football. Similarities between sports were observed in the most common injury types (sprains and concussions), locations (lower extremity and head), and mechanisms (direct player contact). Upper extremity injuries were more common in rugby, and the rate of season-ending injuries was similar between sports.

Objective: Clinical reviews of practice outcomes of adolescent patients who have received electroconvulsive therapy (ECT) remain relatively rare. This study reports the clinic practice and outcome of adolescents receiving ECT at a tertiary medical center. Methods: From April 1991 through November 2013, 51 adolescents (30 female; mean [SD] age, 16.8 [1.6] years) received ECT. The electronic medical record at the time of the first ECT session was reviewed for the clinical diagnosis, ECT lead placement and general administration, seizure duration, adverse effects, concurrent medications, and clinical outcome. Results: ECT was recommended for primary mood and psychotic disorders or catatonia. Patients received a mean (SD) of 9.3 (3.5) treatments, with initial bitemporal lead placement in 36 patients (71%). Thirty-nine patients (77%) were much or very much improved based on Clinical Global Impressions–Improvement scale at the end of the acute treatment. Prolonged seizure duration (>120 seconds) was relatively common (63%) but appeared to decrease in older patients. Conclusions: This report describes the largest group of adolescents receiving ECT since 1947, and supports ECT as a safe and effective modality for most treatment-recalcitrant psychiatric illness in youth.

Objectives To test the external validity of a previously developed risk table, designed to predict the probability of a positive bone scan among men with non‐metastatic (M0) castration‐resistant prostate cancer ( CRPC ), in a separate cohort. Patients and Methods We retrospectively analysed 429 bone scans of 281 patients with CRPC , with no known previous metastases, treated at three Veterans Affairs Medical Centers. We assessed the predictors of a positive scan using generalized estimating equations. Area under the curve ( AUC ), calibration plots and decision‐curve analysis were used to assess the performance of our previous model to predict a positive scan in the current data. Results A total of 113 scans (26%) were positive. On multivariable analysis, the only significant predictors of a positive scan were log‐transformed prostate‐specific antigen ( PSA ): hazard ratio ( HR ) 2.13; 95% confidence interval ( CI ) 1.71–2.66 ( P < 0.001) and log‐transformed PSA doubling time ( PSADT ): HR 0.53; 95% CI 0.41–0.68 ( P < 0.001). Among men with a PSA level <5 ng/ mL , the rate of positive scans was 5%. The previously developed risk table had an AUC of 0.735 to predict positive bone scan with excellent calibration, and provided additional net benefit in the decision‐curve analysis. Conclusion We have validated our previously developed table to predict the risk of a positive bone scan among men with M0/Mx CRPC . Use of this risk table may allow better tailoring of patients' scanning to identify metastases early, while minimizing over‐imaging. Regardless of PSADT , positive bone scans were rare in men with a PSA <5 ng/ mL .

Dysrhythmias and Death in BiMVPIntroductionBileaflet mitral valve prolapse (BiMVP) is common among survivors of otherwise unexplained sudden cardiac death, but prognostic implications of BiMVP are unknown. This study evaluated whether patients with BiMVP are at higher risk for ventricular dysrhythmias, ICD placement, or death compared to controls with either single‐leaflet mitral valve prolapse (SiMVP) or no mitral valve prolapse (MVP).Methods and ResultsThis retrospective, matched cohort study included 18,786 patients who underwent echocardiography at Mayo Clinic between June 1990 and September 2014. The study included three cohorts: BiMVP, SiMVP, and controls without MVP. We assessed rates of ventricular dysrhythmias, ICD placement, and all‐cause mortality between groups. BiMVP was associated with higher rates of ventricular tachycardia compared to SiMVP and controls (adjusted HR 1.48 [1.14–1.92], P = 0.003 and 1.40 [1.04–1.88], P = 0.026, respectively); however, there were no statistically significant differences in rates of ventricular fibrillation/cardiac arrest or ICD placement between groups. BiMVP was associated with a lower rate of all‐cause mortality compared to SiMVP and controls (adjusted HR 0.86 [0.79–0.94], P = 0.0008, and 0.55 [0.50–0.60], P < 0.0001, respectively).ConclusionAlthough BiMVP is associated with ventricular tachycardia, it is not associated with an increased risk of cardiac arrest/ventricular fibrillation or ICD implantation and is, paradoxically, associated with a better survival compared to SiMVP or matched controls. The findings suggest that, despite its association with ventricular tachycardia, BiMVP in the absence of other risk factors does not seem to portend a poor prognosis at the population level.

SummaryTo examine the effectiveness of an initial management strategy of watchful waiting for follicular lymphoma (FL) in clinical practice, we compared outcomes for patients diagnosed 2004–2007 in the United States initially managed with watchful waiting with outcomes following initial rituximab monotherapy and chemoimmunotherapy. In total, 1754 stage II–IV patients in the National LymphoCare Study underwent watchful waiting (n = 386), rituximab monotherapy (n = 296) or rituximab plus chemotherapy (n = 1072) as initial management strategy. Female patients and those who received treatment in the Northeast or in an academic setting more commonly underwent watchful waiting versus initial chemoimmunotherapy; whereas patients with grade 3 histology, anaemia, elevated lactate dehydrogenase, extranodal involvement, B symptoms or performance status ≥1 more commonly received chemoimmunotherapy. Although time to new treatment and progression‐free survival following first‐ and second‐line therapy were improved with chemoimmunotherapy, and time to chemotherapy was improved with rituximab monotherapy, there were no differences in overall survival between watchful waiting and chemoimmunotherapy or rituximab monotherapy. With 8‐year overall survival estimates of 74%, initial management with watchful waiting in the context of sequential therapy remains a viable option for FL patients in the modern era. This trial was registered at www.clinicaltrials.gov (NCT00097565).