Research Spotlight

Posted September 15th 2018

Refinement of anatomic indications for the Nellix System for endovascular aneurysm sealing based on 2-year outcomes from the EVAS FORWARD IDE trial.

Clifford J. Buckley M.D.

Clifford J. Buckley M.D.

Carpenter, J. P., J. S. Lane, 3rd, J. Trani, S. Hussain, C. Healey, C. J. Buckley, H. Hashemi and R. Cuff (2018). “Refinement of anatomic indications for the Nellix System for endovascular aneurysm sealing based on 2-year outcomes from the EVAS FORWARD IDE trial.” J Vasc Surg 68(3): 720-730.e721.

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BACKGROUND: The Nellix System (Endologix, Inc, Irvine, Calif) for endovascular aneurysm sealing (EVAS) is a novel approach to abdominal aortic aneurysm treatment and conceptually different from endovascular aneurysm repair, whereby polymer is employed to fill and actively manage the abdominal aortic aneurysm sac. One-year safety and effectiveness results of the Nellix pivotal trial demonstrated encouraging outcomes with very low morbidity and mortality and high procedural and treatment success. Two-year imaging revealed a signal of migration, leading to a field safety notification issued by the manufacturer on October 21, 2016, and a dedicated root cause analysis, resulting in refinements to the instructions for use (IFU). We report the 2-year results of the investigational device exemption pivotal trial stratified according to the new and original criteria for selection of patients. METHODS: Comprehensive engineering evaluations, statistical analyses, and clinical assessments were conducted looking at patients enrolled in the pivotal trial (N = 150), roll-in cohort (N = 29), and continued access program (N = 154). All patients in all cohorts were treated on-IFU at the time of enrollment. Logistic regression models supported the mechanism that migration with Nellix is associated with a small aortic flow lumen relative to a large aneurysm thrombus burden and large aortic neck diameters. Based on these findings, refinements to the IFU criteria were applied, excluding patients with a thrombus index (maximum aneurysm sac/maximum flow lumen diameter) >1.4, aortic neck diameter >28 mm, and aortic neck conicity (>10% diameter change along the infrarenal neck) and requiring a 10-mm distal seal zone in the iliac artery. RESULTS: Freedom from all-cause mortality at 2 years was 94%. Patient outcomes were then stratified on the refined morphologic criteria and analyzed retrospectively. Two-year freedom from composite endoleak was high among both cohorts (95% on-IFU vs 92% off-IFU). Freedom from migration was 97.7% on-IFU vs 93.2% off-IFU (P = .0125). Freedom from aneurysm enlargement was 98.1% on-IFU vs 93.5% off-IFU (P value is not available because of failure of log-rank test assumptions). Composite freedom from migration, type IA endoleak, or aneurysm expansion was 95.9% among the on-IFU cohort vs 85.1% in the off-IFU cohort (P = .0017). CONCLUSIONS: Consistent with the introduction of a novel therapy, the presentation of failure modes of EVAS over time was inevitable. Using detailed imaging as well as engineering and statistical analysis, we were able to understand risk factors for adverse events specific to EVAS and defined those patients best suited for Nellix. With this EVAS-specific approach to defining IFU, on-IFU patients were identified as those with large aneurysms with little thrombus that would be prone to type II endoleaks and sac expansion with traditional devices. When treated with Nellix, these patients were predicted to experience exceptional results, especially with regard to a low composite endoleak rate and low all-cause mortality.


Posted September 15th 2018

Clinical Leaflet Thrombosis in Transcatheter and Surgical Bioprosthetic Aortic Valves by 4DCT.

Michael J. Mack M.D.

Michael J. Mack M.D.

Basra, S. S., A. Gopal, K. R. Hebeler, H. Baumgarten, A. Anderson, S. P. Potluri, W. T. Brinkman, M. Szerlip, D. Gopal, G. Filardo, J. M. DiMaio, D. L. Brown, P. A. Grayburn, M. J. Mack and E. M. Holper (2018). “Clinical Leaflet Thrombosis in Transcatheter and Surgical Bioprosthetic Aortic Valves by 4DCT.” Ann Thorac Surg. Aug 25. [Epub ahead of print].

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BACKGROUND: The incidence of leaflet thrombosis after transcatheter aortic valve replacement (TAVR) with active surveillance by 4- Dimensional Computed Tomography (4DCT) ranges from 7% to 14%. The incidence of leaflet thrombosis when 4DCT is performed for clinical and echocardiographic indications is unknown. METHODS: All patients with prior TAVR or surgical aortic valve replacement (SAVR) that underwent evaluation between 10/2015 – 1/2017 at our institution and had clinical or echocardiographic indications of leaflet thrombosis were evaluated by 4DCT. Indications for 4DCT included: A) Echocardiographic: 1) Interval increase in mean gradient >/=10 mmHg; 2) Interval decrease in ejection fraction (>/=10 percent) 3) Thrombus seen on TTE 4) Persistent or increasing paravalvular leak 4) Valve dehiscence or thickened leaflets seen on TTE; B) Clinical: 1) Stroke 2) TIA 3) New/worsening heart failure RESULTS: 612 patients underwent TAVR during the study period. 101 patients (55 TAVR; 46 SAVR) met the criteria for 4DCT imaging. Leaflet thrombosis was seen in 17/55 (30.9%) TAVR and 15/46 (32.6%) SAVR patients. Follow-up imaging with 4DCT after treatment with anticoagulation showed improvement/resolution in thrombus burden and leaflet excursion in all TAVR and 2/3rd SAVR patients. CONCLUSIONS: In patients with clinical or echocardiographic indications suggestive of leaflet thrombosis, 1/3rd of patients were found to have evidence of leaflet thrombosis using 4DCT. This allowed tailored anticoagulation therapy with resolution of the thrombus in most patients avoiding unnecessary anticoagulation in the remaining 2/3rds of patients.


Posted September 15th 2018

Long-Term Outcomes From Repeated Smoking Cessation Assistance in Routine Primary Care.

Elisa L. Priest Dr.P.H.

Elisa L. Priest Dr.P.H.

Bailey, S. R., V. J. Stevens, S. P. Fortmann, S. E. Kurtz, M. A. McBurnie, E. Priest, J. Puro, L. I. Solberg, R. Schweitzer, A. L. Masica and B. Hazlehurst (2018). “Long-Term Outcomes From Repeated Smoking Cessation Assistance in Routine Primary Care.” Am J Health Promot 32(7): 1582-1590.

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PURPOSE: To test the association between repeated clinical smoking cessation support and long-term cessation. DESIGN: Retrospective, observational cohort study using structured and free-text data from electronic health records. SETTING: Six diverse health systems in the United States. PARTICIPANTS: Patients aged >/=18 years who were smokers in 2007 and had >/=1 primary care visit in each of the following 4 years (N = 33 691). MEASURES: Primary exposure was a composite categorical variable (comprised of documentation of smoking cessation medication, counseling, or referral) classifying the proportions of visits for which patients received any cessation assistance (<25% (reference), 25%-49%, 50%-74%, and >/=75% of visits). The dependent variable was long-term quit (LTQ; yes/no), defined as no indication of being a current smoker for >/=365 days following a visit where nonsmoker or former smoker was indicated. ANALYSIS: Mixed effects logistic regression analysis adjusted for age, sex, race, and comorbidities, with robust standard error estimation to account for within site correlation. RESULTS: Overall, 20% of the cohort achieved LTQ status. Patients with >/=75% of visits with any assistance had almost 3 times the odds of achieving LTQ status compared to those with <25% visits with assistance (odds ratio = 2.84; 95% confidence interval: 1.50-5.37). Results were similar for specific assistance types. CONCLUSIONS: These findings provide support for the importance of repeated assistance at primary care visits to increase long-term smoking cessation.


Posted September 15th 2018

Increasing Health Care Burden of Chronic Liver Disease Compared With Other Chronic Diseases, 2004-2013.

Sumeet K. Asrani M.D.

Sumeet K. Asrani M.D.

Asrani, S. K., M. Kouznetsova, G. Ogola, T. Taylor, A. Masica, B. Pope, J. Trotter, P. Kamath and F. Kanwal (2018). “Increasing Health Care Burden of Chronic Liver Disease Compared With Other Chronic Diseases, 2004-2013.” Gastroenterology 155(3): 719-729.e714.

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BACKGROUND & AIMS: Chronic liver disease (CLD) is a common and expensive condition, and studies of CLD-related hospitalizations have underestimated the true burden of disease. We analyzed data from a large, diverse health care system to compare time trends in CLD-related hospitalizations with those in congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD). METHODS: We collected data from a large health care system in Texas on hospitalizations related to CLD (n = 27,783), CHF (n = 60,415), and COPD (n = 34,199) from January 1, 2004 through December 31, 2013. We calculated annual hospitalization rates (per 100,000) and compared hospital course, inpatient mortality, ancillary services, and readmissions. RESULTS: Compared with patients with CHF (median age, 71 years) or COPD (median age, 69 years), patients with CLD were significantly younger (median age, 57 years) (P < .01 vs CHF and COPD). Higher proportions of patients with CLD were uninsured (11.7% vs 5.4% for CHF and 5.4% for COPD, P < .01) and Hispanic (17% for CLD vs 9.3% for CHF and 5.0% for COPD, P < .01). A lower proportion of patients with CLD had Medicare (41.5% vs 68.6% with CHF and 70.1% with COPD, P < .01). From 2004 through 2013, the rate of CLD-related hospitalization increased by 92% (from 1295/100,000 to 2490/100,000), compared with 6.7% for CHF (from 3843/100,000 to 4103/100,000) and 48.8% for COPD (from 1775/100,000 to 2642/100,000). During this time period, CLD-related hospitalizations covered by Medicare increased from 31.8% to 41.5%, whereas hospitalizations covered by Medicare did not change for CHF (remained at 70%) or COPD (remained at 70%). Patients with CLD had longer hospital stays (7.3 days vs 6.2 days for CHF and 5.9 days for COPD, P < .01). A higher proportion of patients with CLD died or were discharged to hospice (14.2% vs 11.5% of patients with CHF and 9.3% of patients with COPD, P < .01), and a smaller proportion had access to postacute care (13.2% vs 23.2% of patients with CHF and 27.4% of patients with COPD, P < .01). A higher proportion of patients with CLD were readmitted to the hospital within 30 days (25% vs 21.9% of patients with CHF and 20.6% with COPD, P < .01). CONCLUSIONS: Patients with CLD, compared with selected other chronic diseases, had increasing rates of hospitalization, longer hospital stays, more readmissions, and, despite these adverse outcomes, less access to postacute care. Disease management models for CLD are greatly needed to manage the anticipated increase in hospitalizations for CLD.


Posted September 15th 2018

The role of depression and social support on readmission rates within one year of traumatic injury.

Ann M. Warren Ph.D.

Ann M. Warren Ph.D.

Agtarap, S., J. Shelley, M. Bennett, J. W. Roden-Foreman, E. Rainey, M. Dome, M. B. Powers, L. B. Petrey and A. M. Warren (2018). “The role of depression and social support on readmission rates within one year of traumatic injury.” Health Psychol 37(9): 799-807.

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OBJECTIVE: Hospital readmission rates have become a quality metric-particularly in trauma and acute care, where up to one third of individuals with traumatic injury return to the hospital. Thus, identifying predictors of readmission is a priority in an effort to reduce readmissions. Based on previous theoretical work, this study tests the utility of social support and depression in predicting readmissions up to one year after initial injury. METHOD: Data from 180 injured individuals admitted to a large, urban Level 1 trauma center were matched to a regional readmissions database. Logistic regression was used to assess whether social support levels or positive depression screens during initial trauma visit predicted unplanned (a) readmissions or (b) emergency/urgent outpatient visits. RESULTS: Within the sample, there were 32 total readmissions and 50 total emergency outpatient encounters following initial injury. Depression continued to be a risk factor for emergency outpatient visits only (OR = 2.75). Patients with greater social integration (OR = 0.78), more guidance (advice or information; OR = 0.72) and more reliable alliance (OR = 0.72) as forms of social support were less likely to readmit. CONCLUSIONS: This study demonstrates the utility of screening for depression and social support in predicting readmission within one year after traumatic injury. Future efforts should continue emphasizing the impact of initial depression and the need for patients to have trusted individuals in their lives to whom they can turn during recovery; doing so may lower the probability that patients return to hospital. (PsycINFO Database Record