Tyrosine kinase domain mutations in chronic myelogenous leukemia patients: A single center experience

Introduction:

Despite the impressive responses achieved with tyrosine kinase inhibitor (TKI) therapy, treatment resistance develops in 16–33% of patients of chronic myelogenous leukemia (CML). Of the BCR-ABL1 dependent mechanisms, mutations in the tyrosine kinase domain (TKD) are the commonest cause of resistance.

Material and Methods:

Allele specific oligonucleotide - polymerase chain reaction (ASO-PCR) was done for testing the six common TKD mutations, T315I, G250E, E255K, M244V, M351T, and Y253F.

Results and Conclusion:

TKD mutation study was done on 83 patients. Of these 44 (53%) were positive for one or more mutations. On analyzing specific mutations, E255K was the commonest mutation seen in 24 (29%) cases, followed by T315I in 23(28%) cases. Y253F mutation was not seen in the present study sample. In the present cohort of 83 patients, 29 (35%) cases were positive for single mutation, 12 (14%) had two mutations and 3 (4%) had three mutations.

Utility of device-derived daily activity, a novel digital biomarker, to predict ventricular arrhythmias – data from the CERTITUDE registry

Background

While there have been prior studies showing an association between activity and outcomes, there have been no studies examining the temporal relationship between device-derived daily activity, a novel digital biomarker, and ventricular tachyarrhythmias (VT).

Purpose

In a big dataset with over 55,000 pacemaker, ICD, and CRT devices, we aimed to identify whether changes in activity predict VT, or else VT predict changes in activity.

Methods

The CERTITUDE registry comprises a de-identified database of over 55,000 U.S. BIOTRONIK pacemaker, ICD, CRT devices, and loop recorders active on Home Monitoring®. Daily data on leads, arrhythmias, and physiological parameters such as activity are captured. Patient activity is reported daily as percentage active during the day, assessed by a one-axis accelerometer at ∼0.4 Hz frequency. Analysis to ascertain temporal changes in device-derived activity associated with treated VT was performed using the first event per device and 7-day activity windows (baseline, pre- and post-event). Baseline period was defined as 31–38 days prior to VT. VT events were categorized by heart rate (≤200 bpm,>200 bpm) and treatment (shock with or without ATP, ATP alone). Differences in activity between baseline, and pre- and post-VT were analyzed using the binomial proportion test.

Results

A total of 16,475 devices (9732 ICDs, 6743 CRT-Ds) had activity data available for analysis. The cumulative follow-up duration was 18,355 years (5.6 million days with transmission). Of the 2636 VT events analyzed, 1409 had a heart rate >200 bpm, and 593 were treated with shock. Patients with VT events >200 bpm treated with shock had a significant reduction in activity post-VT with a median −8.7% reduction (IQR −24.6%; 7.3%, p<0.001). However, there was no reduction in activity before the VT>200 bpm (p=0.690) (Figure). VT events >200 bpm treated with ATP alone were not associated with reduction in activity before or after the episode. Similarly, VT events ≤200 bpm treated with shock were also associated with a reduction in activity following the event (−5.8%, IQR −29.5, 12.3%, p=0.003), but not prior to the VT event.

Conclusions

In this report from the CERTITUDE registry, we have shown a temporal decline in device-derived activity following ventricular arrhythmias>200 bpm and ≤200 bpm treated with a shock, but not in patients treated with ATP. Monitoring device-derived activity post-VT events with a shock could provide relevant clinical information and potentially warrant intensified treatment.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Biotronik

A novel machine learning algorithm has the potential to reduce by 1/3 the quantity of ILR episodes needing review

Background

Implantable Loop Recorders (ILRs) are increasingly used and generate a high workload for timely adjudication of ECG recordings. In particular, the excessive false positive rate leads to a significant review burden.

Purpose

A novel machine learning algorithm was developed to reclassify ILR episodes in order to decrease by 80% the False Positive rate while maintaining 99% sensitivity.

This study aims to evaluate the impact of this algorithm to reduce the number of abnormal episodes reported in Medtronic ILRs.

Methods

Among 20 European centers, all Medtronic ILR patients were enrolled during the 2nd semester of 2020. Using a remote monitoring platform, every ILR transmitted episode was collected and anonymised.

For every ILR detected episode with a transmitted ECG, the new algorithm reclassified it applying the same labels as the ILR (asystole, brady, AT/AF, VT, artifact, normal). We measured the number of episodes identified as false positive and reclassified as normal by the algorithm, and their proportion among all episodes.

Results

In 370 patients, ILRs recorded 3755 episodes including 305 patient-triggered and 629 with no ECG transmitted. 2821 episodes were analyzed by the novel algorithm, which reclassified 1227 episodes as normal rhythm. These reclassified episodes accounted for 43% of analyzed episodes and 32.6% of all episodes recorded.

Conclusion

A novel machine learning algorithm significantly reduces the quantity of episodes flagged as abnormal and typically reviewed by healthcare professionals.

Funding Acknowledgement

Type of funding sources: None. Figure 1. ILR episodes analysis

P577Early experience with the first pacemakers to directly connect with smart devices for remote monitoring

Background

Remote monitoring is associated with improved patient outcomes; however, adoption and adherence to remote monitoring via home-based consoles remains suboptimal. BlueSync technology in new generation pacemaker and CRT-P models enables the implanted device to communicate directly with patient-owned, Bluetooth-equipped smartphones/tablets and an app (MyCareLink Heart). The app can automatically retrieve information from the cardiac device and transmit the data to the remote network, eliminating the need for traditional remote monitoring consoles.

Objectives

To characterize the communication process between implanted pacemakers and smart device remote monitoring apps by assessing the success of prescheduled remote transmissions in the first month of follow-up. Additionally, to assess the feedback of both patients and clinicians about the process of device pairing.

Methods

Enrollment in the BlueSync Field Evaluation began in April 2018 and was completed November 2018. Follow-up is ongoing. Prior to enrollment in the evaluation, patients completed the device pairing process with the app using their own compatible smartphone or tablet. Patient and clinician questionnaires were completed at the time of the device pairing process. After enrollment, successful completion of scheduled transmissions occurring in the first month were analyzed.

Results

Preliminary data includes 241 enrolled patients with mean age of 64.7±15.5 yrs (min 20, max 90 yrs), who completed device pairing between their implanted device and their smart device app. Of enrolled patients, 79% felt that the device paring was easy to do, 85% were satisfied with the amount of time it took to complete it, and 93% felt that they would be comfortable using the app. Clinicians reported that 67% of the device pairings took less than 20 minutes and 78% felt patients would be able to use the app independently. At the time of analysis 174 patients had at least one scheduled transmission within the first month, and collectively had a total of 322 scheduled transmissions. Out of these, 309 (96%, 95% CI: 93%-98%) were successfully completed.

MyCareLink Heart App

Conclusions

Initial experience with the world's first app based remote monitoring system for Bluetooth enabled pacemakers demonstrated success to scheduled transmissions in the first month across a wide range of patient ages. Patients and clinicians reported high satisfaction with this novel technology.

Acknowledgement/Funding

Medtronic PLC

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Securing an OTL-HNS residency: how competitive is it? Comparing medical student perceptions to actual Canadian statistics

BACKGROUND

The residency match is an important event in an aspiring physician's career. Otolaryngology - Head and Neck Surgery (OTL-HNS) is a surgical specialty that has enjoyed high numbers of applicants to its residency programs. However, recent trends in Canada show a decline in first-choice applicants to several surgical fields. Factors thought to influence a medical student's choice include role models, career opportunities and work-life balance. The notion of perceived competitiveness is a factor that has not yet been explored. This study sought to compare competitiveness of OTL-HNS, as perceived by Canadian medical students to residency match statistics published yearly by CaRMS (Canadian Residency Matching Service), with the hope of informing future decisions of surgical residency programs.

METHODS

An electronic survey was created and distributed to all medical students enrolled in the 17 Canadian medical schools. After gathering demographic information, students were asked to rank what they perceived to be the five most competitive disciplines offered by CaRMS. They were also asked to rank surgical specialties from most to least competitive. Publically available data from CaRMS was then collected and analyzed to determine actual competitiveness of admissions to Canadian OTL-HNS residency programs.

RESULTS

1194 students, from first to fourth year of medical school, completed the survey. CaRMS statistics over the period from 2008 to 2014 demonstrated that the five most competitive specialties were Plastic Surgery, Dermatology, Ophthalmology, Emergency Medicine and OTL-HNS. Among surgical disciplines, OTL-HNS was third most competitive, where on average 72% of students match to their first-choice discipline. When students were questioned, 35% ranked OTL-HNS amongst the top five most competitive. On the other hand 72%, 74% and 80% recognized Opthalmology, Dermatology and Plastic Surgery as being among the five most competitive, respectively. We found that fourth-year medical students were significantly more knowledgeable about the competitiveness of both OTL-HNS and Plastic Surgery compared to first-year students (p < 0.01).

CONCLUSION

Overall, Canadian medical students may underestimate the competitiveness of OTL-HNS. Furthermore, competitiveness would appear to be a concept that resonates with medical students during the match process.

Visceral Leishmaniasis in a Non-Endemic Area of India

The study included 57 patients with visceral leishmaniasis. The average duration of symptoms was 3.8 ± 3.55 months and pancytopenia was the commonest haematological abnormality. The parasite load directly correlated with the degree of anaemia at presentation (P=0.03). Splenic regression took 9.58 ±4.5 days and haematological parameters recovered in 14.5±9.07 days. There were five deaths over the five-year study duration. Leishmaniasis was not the first diagnosis in 14 patients, of whom eight were residents of non-endemic regions. Diagnosis was achieved in 13.5 days in these patients, compared to 4.5 days in patients where leishmaniasis was suspected at the outset.

Vortex-dislodged cells from bone marrow trephine biopsy yield satisfactory results for flow cytometric immunophenotyping

INTRODUCTION

A good bone marrow (BM) sample is essential in evaluating many hematologic disorders. An unsuccessful BM aspiration (BMA) procedure precludes a successful flow cytometric immunophenotyping (FCI) in most hematologic malignancies. Apart from FCI, most ancillary diagnostic techniques in hematology are less informative. We describe the feasibility of FCI in vortex-dislodged cell preparation obtained from unfixed trephine biopsy (TB) specimens.

METHODS

In pancytopenic patients and dry tap cases, routine diagnostic BMA and TB samples were complemented by additional trephine biopsies. These supplementary cores were immediately transferred into sterile tubes filled with phosphate-buffered saline, vortexed, and centrifuged. The cell pellet obtained was used for flow cytometric immunophenotyping.

RESULTS

Of 7955 BMAs performed in 42 months, 34 dry tap cases were eligible for the study. Vortexing rendered a cell pellet in 94% of the cases (32 of 34), and FCI rendered a rapid diagnosis in 100% of the cases (32 of 32) where cell pellets were available.

CONCLUSION

We describe an efficient procedure which could be effectively utilized in resource-limited centers and reduce the frequency of repeat BMA procedures.

Improving operation notes and postoperative care: an audit of current practice

The operation note is the single most important document in surgical practice. Ninety one operation notes were assessed on their adherence to guidelines, as well as their legibility and ability to inform postoperative care; as judged by five different healthcare professionals. Results showed a deficiency in essential information and poor legibility overall. Re-audit of 103 operation notes after intervention showed an improvement in nearly all criteria measured. The results indicate that education about current guidelines and an increase in word processing of operation notes improves quality of documentation, and therefore of postoperative care.