P1019Validation of a risk score to predict the need for pacemaker implantation after transcatheter aortic valve replacement

Background

New conduction abnormalities necessitating pacemaker implantation (PMI) is a common occurrence after TAVR. There is an increased rate of PMI in the those receiving the most contemporary implanted valve, the Edwards Sapien-3 (S3), compared to prior generation balloon expandable valves. We previously described predictors of PMI in a large cohort. Herein we sought to validate these predictors of PMI in a subsequent validation cohort.

Methods

We evaluated all patients undergoing first time elective TAVR with S3 at our institution (n=326). We developed a risk score based on a predictive model we have previously described. Patients received one point for each of the following: history of syncope, oversizing of the valve >16%, baseline right bundle branch block morphology, and two points for a QRS duration >115 ms. We performed regression analysis of the risk score and need for PMI. We also evaluated the performance of the risk score using ROC analysis.

Results

Thirty patients (8%) of the total cohort had need for PMI after S3 implantation. Those with PMI had a higher rate of pre-existing infra-nodal conduction system disease – including QRS duration >115ms (57% vs. 20%, p<0.001) and right bundle branch block (RBBB) morphology (47% vs. 10%, p<0.001) - as well as more frequent valve oversizing >15.7% (47% vs. 23%, p<0.01). There was no significant difference in a history of syncope (10% vs. 8%, p=0.72) between groups. The PMI risk score had an area under the curve of 0.753 on ROC analysis. The PMI risk score was significantly associated with PMI (OR 2.37; 95% CI [1.64–3.34], p<0.001).

Rate of PMI Stratified by Risk Score

Conclusions

The PMI risk score was strongly predictive of the need for PMI after implantation of the S3 valve in a large validation cohort. The PMI risk score performed well in sensitivity analysis. This PMI risk score represents a simple tool to help further risk stratify patients being considered for TAVR.

Abstract LB-B25: Preliminary phase I data comparing HuMab-5B1 (MVT-5873), a monoclonal antibody targeting sLea, as a single agent and in combination with first line nab-paclitaxel and gemcitabine in patients with CA19-9 positive pancreatic cancer

IntroductionMVT-5873, a fully human IgG1 monoclonal antibody (mAb), targets sialyl Lewis A (sLea), an epitope on CA19-9. CA19-9 is expressed in pancreatic (PDAC) and other GI cancers, plays a role in tumor adhesion and metastasis, and is a marker of an aggressive tumor phenotype. MVT-5873 is active as a single agent and in combination with nab-paclitaxel (nab-P) and gemcitabine (gem) in murine xenografts. MethodsSingle agent: for each 28-day treatment cycle, MVT-5873 was given IV every second week (Group 1) or weekly (Group 2) at doses ranging from 1 to 3 mg/kg. Combination with nab-P and gem: for each 28-day treatment cycle MVT-5873 was administered IV weekly (1.0mg/kg or 0.125mg/kg) followed by IV infusion of 125 mg/m2 of nab-P and then 1000mg/m2 gem, on day 1, 8 and 15 (Group 3). Eligible patients had recurrent progressive (single agent) or newly diagnosed (combination), locally-advanced or metastatic PDAC or other CA19-9+ malignancy and ECOG PS ≤1. Dose escalation followed a standard 3+3 design with a 10 patient expansion at the maximally tolerated dose (MTD). Trial endpoints include safety, MTD, dose limiting toxicities (DLT), pharmacokinetics (PK) and efficacy. Exploratory endpoints include changes in serum CA19-9 levels.ResultsAs of 7-September-2017, data are available for single agent N=32 in Groups 1 (N=9) and 2 (N=23) at 1, 2, 2.5 and 3 mg/kg and combination Group 3 (N=6) at 1.0 and 0.125mg/kg. DLTs of transient grade 3 elevations in AST, ALT, and total bilirubin were encountered in the single agent groups at 2, 2.5 and 3mg/kg in both single agent groups and in the combination group at 1mg/kg. Single agent liver function laboratory abnormalities typically emerged and resolved within a week of dosing although they were more persistent in the combination treated patients. Other toxicities associated with all groups included low grade GI toxicity (abdominal pain/cramps/diarrhea/nausea) and infusion reactions. Infusion reactions were mitigated with pre-medications and an increase in the infusion time. Combination DLTs for MVT-5873 at 1mg/kg included AST, ALT, and bilirubin elevations as well as neutropenia and pneumonitis resulted in significant dose de-escalation. MVT-5873 dosed at 0.125 mg/kg in combination was generally well tolerated. Single agent activity included SD of &gt;4 months in 5 of 32 of patients with an MTD established at 1 mg/kg. Combination activity at 0.125 mg/kg MVT-5873 with nab-P/gem included 2 PRs and 1 SD in 3 patients. Interestingly, sustained suppression below ULN of CA19-9 levels was observed in 3 of the 6 patients in the combination arm and &gt;95% CA19-9 reduction at the 0.125mg/kg combination dose. Dose escalation in this arm is in progress, and updated safety, PK/PD, and efficacy data will be presented.ConclusionsSingle agent MVT-5873 appears safe and tolerable at biologically active doses. DLTs included reversible liver function abnormalities. Determination of the MTD in combination with first line nab-P/gem is underway and preliminary response data are encouraging. Overall, the safety profile, efficacy, and reductions in serum CA19-9 levels over time support further development of MVT-5873 in this indication both as a single agent and in combination.

Citation Format: Eileen Mary O'Reilly, Judy Sing-Zan Wang, Kenneth H. Yu, Maeve Aine Lowery, Anna M. Varghese, Johanna C. Bendell, Erkut Hasan Borazanci, Hayley Estrella, Kimberly Fowler, Mariella Hoskins, Stephanie Bussen, Teresa J. Melink, Christine M. Kearns, H Toni Jun, Paul W. Maffuid, John C. Gutheil, Todd Michael Bauer. Preliminary phase I data comparing HuMab-5B1 (MVT-5873), a monoclonal antibody targeting sLea, as a single agent and in combination with first line nab-paclitaxel and gemcitabine in patients with CA19-9 positive pancreatic cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr LB-B25.

Transvenous echo Doppler in baboons: a new window to the cardiovascular system

Ultrasound examinations of the heart and major peripheral arteries have been performed as separate procedures; both potentially limited by suboptimal views in certain subjects and the inability to obtain ideal pictures of particular intracardiac structures. Transvenous ultrasound may offer new advantages in certain areas, we therefore studied six adult baboons using a single-plane 5.5-10 MHz transducer mounted on a 10 French (10F) catheter, introduced via the right femoral vein and positioned under fluoroscopic control. Imaging and Doppler studies were performed to delineate cardiovascular anatomy as well as ventricular function response to positive (dobutamine) and negative inotropic (esmolol) agents. The procedure was safe and feasible in all cases. Clear and novel two-dimensional and flow information were obtained from the iliac arteries, descending aorta, both renal artery origins, ascending aorta, including the aortic arch, main pulmonary artery and its bifurcation, as well as head and neck vessels. Novel intracardiac views were obtained, including right ventricular long axis, left ventricular apex and 'flask' views of the left ventricle. Excellent dynamic information for left ventricular function was also available [e.g. myocardial Vmax of the anterior left ventricular wall was 6.8+/-2.5 cm/s at rest, 14.6+/-5.5 cm/s after dobutamine (P=0.009) and 4.5+/-1 cm/s after esmolol (P=0.03 compared with control)]. We conclude that, in adult primates, transvenous ultrasound safely and reliably provides novel information of cardiovascular structure and function.

Women's lived experience of conceptualizing the self: implications for health care practice

In this article we describe a unique qualitative research design in which we used our own lived experiences as the basis for understanding theories of the self. Our purpose in this study was to (a) broaden current understandings of self theory, (b) juxtapose theories of the self with lived experiences of selfhood, and (c) use these new understandings to inform health care practice. The participants were four Canadian middle-aged female academic and health care practitioners. We conducted unstructured, open-ended interviews. Through a collaborative, interpretive process, four recurring themes emerged from the women's narratives: struggling for authenticity, inner knowing, changing over time, and the contextual self. We address the need for practitioners to understand theories of the self--their own and their clients--and how these theories impact their clinical practice.

The quality of medical evidence in hematology-oncology

PURPOSE

The purpose of this study was to evaluate the quality of the medical evidence available to the clinician in the practice of hematology/oncology.

METHODS

We selected 14 neoplastic hematologic disorders and identified 154 clinically important patient management decision/interventions, ranging from initial treatment decisions to those made for the treatment of recurrent or refractory disease. We also performed a search of the scientific literature for the years 1966 through 1996 to identify all randomized controlled trials in hematology/oncology.

RESULTS

We identified 783 randomized controlled trials (level 1 evidence) pertaining to 37 (24%) of the decision/interventions. An additional 32 (21%) of the decision/interventions were supported by evidence from single arm prospective studies (level 2 evidence). However, only retrospective or anecdotal evidence (level 3 evidence) was available to support 55% of the identified decision/interventions. In a retrospective review of the decision/interventions made in the management of 255 consecutive patients, 78% of the initial decision/interventions in the management of newly diagnosed hematologic/oncologic disorders could have been based on level 1 evidence. However, more than half (52%) of all the decision/interventions made in the management of these 255 patients were supported only by level 2 or 3 evidence.

CONCLUSIONS

We conclude that level 1 evidence to support the development of practice guidelines is available primarily for initial decision/interventions of newly diagnosed diseases. Level 1 evidence to develop guidelines for the management of relapsed or refractory malignant diseases is currently lacking.

Transforming our vision: emancipatory career planning for nurses

Canadian nurses are experiencing profound and often disturbing changes in the health care sector. Not only have the number of jobs decreased but the nature and expectations of those jobs are changing dramatically. While these changes have raised nurses' anxiety, the changes simultaneously have presented nurses with an opportunity to transform their vision of nursing and their role in health care. This article describes a career planning pilot project for nurses which employed Freire's model of emancipatory learning. Based on the theoretical foundations of narrative psychology and critical social theory a series of four workshops were offered. Comments from the evaluation results indicate that the workshop was a transformative experience for the participants. Future implications for career planning for nurses are discussed.

Cloning and characterisation of the Schizosaccharomyces pombe rad8 gene, a member of the SNF2 helicase family

The Schizosaccharomyces pombe rad8 mutant is sensitive to both UV and gamma irradiation. We have cloned the rad8 gene by complementation of the UV sensitivity of a rad8.190 mutant strain. The gene comprises an open reading frame of 3.4 kb which does not contain any introns and is capable of encoding a 1133 amino acid protein of 129 kDa. Deletion of the gene indicates that it is not essential for cell viability. Recognisable motifs are present for a nuclear localisation signal, a RING finger and helicase domains. The predicted protein is a member of the SNF2 subfamily of proteins and shows particular homology to the Saccharomyces cerevisiae RAD5 protein. Double mutant analysis demonstrated that the rad8 mutant is not epistatic to mutants in the excision repair pathway (rad13) or checkpoint pathway (rad9). Analysis of radiation sensitivity though the cell cycle indicates that, unlike most other rad mutants, rad8 is most sensitive to irradiation during the G1/S period.