Citations

Coronary Artery Ventricular Tachycardia. Background The coronary cusps have been well described as a successful site for ablation in patients with symptomatic outflow tract ventricular tachycardia. The earliest site of activation is rarely found at the ostia or into the main coronary arteries. The exact anatomic substrate, diagnostic characteristics, and therapeutic approaches for such instances are poorly understood. Methods We retrospectively reviewed outflow tract ventricular arrhythmia (OTVA) ablations done at Mayo Clinic Rochester from 2003 to 2011 (total VT: 414; outflow tract VT: 106). Three cases were identified where the earliest site of activation was not within the cusp but rather at or within the coronary ostia (3/414 for all VT: 0.7%; 3/106 for all OTVT: 2.8%). Results In 1 patient, the left main coronary artery (LMCA) was found to have electrograms (EGMs) recorded with bipolar mapping that preceded activation in the cusps or the left ventricular outflow tract. In 2 cases, the right coronary ostium and proximal right coronary artery recorded the earliest signals. Intracardiac echocardiographic guidance was used to successfully ablate these arrhythmias targeting the aortic route (1 patient) or the right coronary cusp (2 patients), and essentially isolated the focus of origin from the ventricular outflow tracts. Detailed mapping of surrounding structures, including the atrial appendages, the contralateral outflow tract, and the coronary venous system excluded far‐field mapping in the artery as a cause for early activation at the ostial location. Local EGM characteristics suggested an unusually lengthy supravalvar myocardial extension as the likely arrhythmogenic substrate. Ablation was successful without coronary arterial or valvular injury and without valvular or root stenosis. Conclusions Endocardial ablation isolating foci of origin in the vicinity of the coronary ostia is a challenging procedure but can be performed safely with appropriate visualization and is effective in the treatment of OTVA.

Time is a ubiquitous but often omitted variable in career selection decisions. This study investigates the impact of temporal elements on career selection decisions, thus advancing our understanding of both career decision making and the impact of timing on decision making. We investigate the influence of timing and duration of experience with career options on career selection decisions in an archival study using medical residents’ rotation schedules. We also investigate factors that mitigate the influence of timing on career selection decisions by examining the interaction of timing with the duration of experience and the diversity of options that an individual experiences. Conditional logit results indicate that decisions often based on career and individual attributes are significantly influenced by the timing and duration of options even when controlling for option attributes. Additionally, significant interactions between timing and diversity of experience and timing and duration of experience revealed boundary conditions for timing. Individuals were more likely to select later-appearing career options when they appeared for a greater duration or when they experienced a greater diversity of options in their schedule. Results illustrate that schedules over which individuals have no control can influence consequential decisions.

Case ReportA 50‐year‐old male with T‐cell lymphoma presented for autologous peripheral blood stem cell transplantation. After granulocyte–colony‐stimulating factor (G‐CSF) mobilization, his peripheral blood CD34+ cell count was 166 × 106/L on the day before collection, which predicted a high yield of CD34+ cells in the apheresis product. The first two collections had yields much lower than expected, triggering an investigation and changes to the apheresis collection methods since mobilization appeared adequate from the peripheral CD34+ values.ResultsChanges to the apheresis collection variables and instrumentation did not improve the yields in the next three collections. The laboratory investigation demonstrated that there was an interfering substance in the patient's plasma that was causing falsely high peripheral blood CD34+ cell values and that the low CD34+ cell yields in the collections were consistent with the actual peripheral blood CD34+ cell value. Based on this finding and after discussion with the clinical service, the patient then received plerixafor to increase the number of circulating CD34+ cells before Collections 6 and 7. The patient went on to achieve the target CD34+ cell dose and subsequently underwent a successful autologous transplant with full hematopoietic engraftment.ConclusionThis case demonstrates the importance of timely and critical review of laboratory results in the context of the specific patient. This case exemplifies how diligent review of laboratory results and open communication among the various teams can positively affect patient outcomes.

Purpose In this study, the authors examined how signal clarity interacts with the use of sentence context information in determining speech-in-noise recognition for children with cochlear implants and children with normal hearing. Method One hundred and twenty sentences in which the final word varied in predictability (high vs. low semantic context) were produced in conversational and clear speech. Nine children with cochlear implants and 9 children with normal hearing completed the sentence-in-noise listening tests and a standardized language measure. Results Word recognition in noise improved significantly for both groups of children for high-predictability sentences in clear speech. Children with normal hearing benefited more from each source of information compared with children with cochlear implants. There was a significant correlation between more developed language skills and the ability to use contextual enhancements. The smaller context gain in clear speech for children with cochlear implants is in accord with the effortfulness hypothesis (McCoy et al., 2005) and points to the cumulative effects of noise throughout the processing system. Conclusion Modifications of the speech signal and the context of the utterances through changes in the talker output hold substantial promise as a communication enhancement technique for both children with cochlear implants and children with normal hearing.

Background— The risks of sports participation for implantable cardioverter-defibrillator (ICD) patients are unknown. Methods and Results— Athletes with ICDs (age, 10–60 years) participating in organized (n=328) or high-risk (n=44) sports were recruited. Sports-related and clinical data were obtained by phone interview and medical records. Follow-up occurred every 6 months. ICD shock data and clinical outcomes were adjudicated by 2 electrophysiologists. Median age was 33 years (89 subjects <20 years of age); 33% were female. Sixty were competitive athletes (varsity/junior varsity/traveling team). A pre-ICD history of ventricular arrhythmia was present in 42%. Running, basketball, and soccer were the most common sports. Over a median 31-month (interquartile range, 21–46 months) follow-up, there were no occurrences of either primary end point—death or resuscitated arrest or arrhythmia- or shock-related injury—during sports. There were 49 shocks in 37 participants (10% of study population) during competition/practice, 39 shocks in 29 participants (8%) during other physical activity, and 33 shocks in 24 participants (6%) at rest. In 8 ventricular arrhythmia episodes (device defined), multiple shocks were received: 1 at rest, 4 during competition/practice, and 3 during other physical activity. Ultimately, the ICD terminated all episodes. Freedom from lead malfunction was 97% at 5 years (from implantation) and 90% at 10 years. Conclusions— Many athletes with ICDs can engage in vigorous and competitive sports without physical injury or failure to terminate the arrhythmia despite the occurrence of both inappropriate and appropriate shocks. These data provide a basis for more informed physician and patient decision making in terms of sports participation for athletes with ICDs.

ABSTRACT We previously showed that culture of samples obtained by prosthesis vortexing and sonication was more sensitive than tissue culture for prosthetic joint infection (PJI) diagnosis. Despite improved sensitivity, culture-negative cases remained; furthermore, culture has a long turnaround time. We designed a genus-/group-specific rapid PCR assay panel targeting PJI bacteria and applied it to samples obtained by vortexing and sonicating explanted hip and knee prostheses, and we compared the results to those with sonicate fluid and periprosthetic tissue culture obtained at revision or resection arthroplasty. We studied 434 subjects with knee ( n = 272) or hip ( n = 162) prostheses; using a standardized definition, 144 had PJI. Sensitivities of tissue culture, of sonicate fluid culture, and of PCR were 70.1, 72.9, and 77.1%, respectively. Specificities were 97.9, 98.3, and 97.9%, respectively. Sonicate fluid PCR was more sensitive than tissue culture ( P = 0.04). PCR of prosthesis sonication samples is more sensitive than tissue culture for the microbiologic diagnosis of prosthetic hip and knee infection and provides same-day PJI diagnosis with definition of microbiology. The high assay specificity suggests that typical PJI bacteria may not cause aseptic implant failure.

We hypothesized that demographic/anthropometric parameters can be used to estimate effective reflecting distance (EfRD), required to derive aortic pulse wave velocity (APWV), a prognostic marker of cardiovascular risk, from peripheral waveforms and that such estimates can discriminate differences in APWV and EfRD with aging and habitual endurance exercise in healthy adults. Ascending aortic pressure waveforms were derived from peripheral waveforms (brachial artery pressure, n = 25; and finger volume pulse, n = 15) via a transfer function and then used to determine the time delay between forward- and backward-traveling waves (Δ tf-b). True EfRDs were computed as directly measured carotid-femoral pulse wave velocity (CFPWV) × ½Δ tf-b and then used in regression analysis to establish an equation for EfRD based on demographic/anthropometric data (EfRD = 0.173·age + 0.661·BMI + 34.548 cm, where BMI is body mass index). We found good agreement between true and estimated APWV (Pearson's R2 = 0.43; intraclass correlation = 0.64; both P < 0.05) and EfRD ( R2 = 0.24; intraclass correlation = 0.40; both P < 0.05). In young sedentary (22 ± 2 years, n = 6), older sedentary (62 ± 1 years, n = 24), and older endurance-trained (61 ± 2 years, n = 14) subjects, EfRD (from demographic/anthropometric parameters), APWV, and ½Δ tf-b (from brachial artery pressure waveforms) were 52.0 ± 0.5, 61.8 ± 0.4, and 60.6 ± 0.5 cm; 6.4 ± 0.3, 9.6 ± 0.2, and 8.1 ± 0.2 m/s; and 82 ± 3, 65 ± 1 and 76 ± 2 ms (all P < 0.05), respectively. Our results demonstrate that APWV derived from peripheral waveforms using age and BMI to estimate EfRD correlates with CFPWV in healthy adults. This method can reliably detect the distal shift of the reflecting site with age and the increase in APWV with sedentary aging that is attenuated with habitual endurance exercise.