Research Spotlight

Mack, M. J. (2018). “Is TAVR Ready for Prime Time in Low-Risk Patients?” J Am Coll Cardiol 72(18): 2106-2108.

Full text of this article.

Transcatheter aortic valve replacement (TAVR) has been demonstrated in randomized controlled trials (RCTs) to be superior to medical therapy in inoperable patients with severe symptomatic aortic stenosis and to be noninferior to surgical aortic valve replacement (SAVR) in high and intermediate surgical risk patients. TAVR has thus become widely accepted as the standard of care in these patient cohorts due in large part to the robust body of evidence generated by 6 RCTs. We also have some outcome data in low-risk patients from a single randomized trial, NOTION (Nordic Aortic Valve Intervention Trial; NCT01057173). There are 2 more RCTs comparing TAVR with SAVR in low surgical risk patients with 2 different devices that have now completed enrollment of approximately 2,000 patients, and the outcomes of these trials are expected to become available in early 2019 . . . With this background in mind, we now consider the study by Waksman et al. reported in this issue of the Journal. It is an observational, nonrandomized study of 200 low surgical risk patients with severe symptomatic aortic stenosis who underwent TAVR. The primary endpoint of the study is all-cause mortality at 30 days. Important exclusions included bicuspid aortic valves and unsuitability for transfemoral access. The mean age was 73.6 years, and the STS PROM (Society of Thoracic Surgeons Predicted Risk of Mortality) was 1.8. A balloon-expandable valve, Sapien 3 (Edwards Lifesciences, Irvine, California), was used in 88.2% of the patients and a self-expanding valve, CoreValve Evolut R (Medtronic, Dublin, Ireland), in 11.8%. Notable procedural findings are that 75% of the procedures were performed without general anesthesia, all by transfemoral access, and there was 1 conversion to surgery due to coronary artery obstruction (0.5%). The 30-day results are excellent in that there was no mortality and a 0.5% stroke rate. Also of note is that there was a low incidence of the need for new permanent pacemaker implantation (5%) and a low rate of new-onset atrial fibrillation (3%), and there were 2 patients (1.0%) with a moderate-severe paravalvular leak at discharge. (Commentary on Waksman et al. 2018. Transcatheter aortic valve replacement in low-risk patients with symptomatic severe aortic stenosis. J Am Coll Cardiol, 72.)

Lytle, M. E., J. West, J. N. Burkes, B. Beteck, T. Fisher, Y. Daoud, D. R. Gable and W. P. Shutze (2018). “Limited Clinical Relevance of Vertebral Artery Injury in Blunt Trauma.” Ann Vasc Surg 53: 53-62.

Full text of this article.

BACKGROUND: Blunt cerebrovascular injury (BCVI), although rare, is more common than previously thought and carries a substantial stroke and mortality risk. The purpose of our study was to evaluate the differences between blunt carotid artery (CA) and vertebral artery (VA) injuries, assess the stroke and death rates related to these injuries, and identify the relationship of Injury Severity Score (ISS) with stroke and mortality in BCVI. METHODS: Using a retrospective review of the trauma registry at a level I trauma center, we identified patients with BCVI. The study period began in January 2003 and ended in July 2014. Demographics, injuries reported, investigative studies performed, and outcomes data were obtained and analyzed. Radiographic images of both blunt CA and VA injuries were reviewed and graded by an independent radiologist, according to the current classification of blunt CA injuries. RESULTS: BCVI involving 114 vessels was identified in 103 patients. This population consisted of 65 males and 38 females with an average age of 45 years (15-92, range). The average ISS was 22 (4-75, range). Cervical spine fracture occurred in 80% of VA injuries (64 total patients). Injuries involved the CA in 33, the VA in 59, and both in 11. The CA group had a higher incidence of traumatic brain injury (61% vs. 46%), ISS (27 vs. 18), and stroke (24% vs. 3%), compared to the VA group. Mortality in the CA group was 30% compared to 3% in the VA group. Patients with high ISS (>/=25) had increased stroke rates compared to those with lower (<25) ISS (19% vs. 6.7%). All mortalities occurred with ISS >25. Logistic regression revealed that vessel injured, ISS, and Glasgow Coma Scale (GCS) were significant risk factors for mortality. Multivariate analysis demonstrated carotid injury, and lowest GCS were independently associated with mortality. CONCLUSIONS: In this comparison of CA and VA injuries in BCVI, VA injuries were more common and more frequently found with cervical spine fractures than CA injuries. However, VA injuries had a lower incidence of CVA and mortality. A high ISS was associated with stroke and mortality while carotid injury and lowest GCS were independently associated with increased mortality.

Kwong, A. J., A. Wall, M. Melcher, U. Wang, A. Ahmed, A. Subramanian and P. Y. Kwo (2018). “Liver Transplantation for HCV Non-Viremic Recipients with HCV Viremic Donors.” Am J Transplant Oct 31. [Epub ahead of print].

Full text of this article.

In the context of organ shortage, the opioid epidemic, and effective direct-acting antiviral (DAA) therapy for hepatitis C (HCV), more HCV-infected donor organs may be used for liver transplantation. Current data regarding outcomes after donor-derived HCV in previously non-viremic liver transplant recipients are limited. Clinical data for adult liver transplant recipients with donor-derived HCV infection from March 2017 to January 2018 at our institution were extracted from the medical record. Ten patients received livers from donors known to be infected with HCV based on positive nucleic acid testing (NAT). Seven had a prior diagnosis of HCV and were treated before liver transplantation. All recipients were non-viremic at the time of transplantation. All 10 recipients derived hepatitis C infection from their donor and achieved sustained virologic response at 12 weeks post-treatment (SVR-12) with DAA-based regimens, with a median time from transplant to treatment initiation of 43 days (IQR 20-59). There have been no instances of graft loss or death, with median follow-up of 380 days (IQR 263-434) post-transplant. Transplantation of HCV-viremic livers into non-viremic recipients results in acceptable short-term outcomes. Such strategies may be used to expand the donor pool and increase access to liver transplantation.

Kraeutler, M. J., K. V. Patel, A. Hosseini, G. Li, T. J. Gill and J. T. Bravman (2018). “Variability in the Clock Face View Description of Femoral Tunnel Placement in ACL Reconstruction Using MRI-Based Bony Models.” J Knee Surg 31(10): 965-969.

Full text of this article.

Though controversial, the “clock face view” of the intercondylar notch remains a way some surgeons communicate regarding placement of the femoral tunnel in anterior cruciate ligament reconstruction. The purpose of this study was to quantify the differences in angle measurement between several previous descriptions of the clock face view by using a new reference standard. Three-Tesla magnetic resonance imaging (MRI) was used to scan 10 human knees to create three-dimensional MRI-based bony models which were used for measurements. A standardized clock face view was developed with the knee flexed to 90 degrees using the junction of the cartilage and cortex of the medial and lateral surfaces of medial and lateral femoral condyles as the 3 o’clock and 9 o’clock, respectively, with the 12 o’clock established as the midpoint of the roof of the intercondylar notch. With the knee viewed at 90 degrees of flexion, an “idealized” femoral tunnel position was plotted on the medial wall of the lateral femoral condyle at 30 degrees (corresponding to the 10 o’clock or 2 o’clock position). The clock faces as described by Edwards et al, Heming et al, and Mochizuki et al were each then overlaid on this same model and the difference in measurement calculated. The average angles measured when the previously described clock faces were projected onto the idealized clock face view comparing a mark made at 30 degrees were 47.7 degrees , 7.2 degrees , and 49.8 degrees for the methods described by Edwards et al, Heming et al, and Mochizuki et al, respectively (all p < 0.001). Significant variation exists between angle measurements in simulated femoral tunnel placement based on the varying descriptions of the intercondylar clock face.

Ko, J. M., K. S. White, A. H. Kovacs, K. M. Tecson, S. Apers, K. Luyckx, C. Thomet, W. Budts, J. Enomoto, M. A. Sluman, J. K. Wang, J. L. Jackson, P. Khairy, S. C. Cook, R. Subramanyan, L. Alday, K. Eriksen, M. Dellborg, M. Berghammer, B. Johansson, A. S. Mackie, S. Menahem, M. Caruana, G. Veldtman, A. Soufi, S. M. Fernandes, E. Callus, S. Kutty, A. Gandhi, P. Moons and A. M. Cedars (2018). “Physical Activity-Related Drivers of Perceived Health Status in Adults With Congenital Heart Disease.” Am J Cardiol 122(8): 1437-1442.

Full text of this article.

Data on the differential impact of physical activity on perceived health status (PHS) in a large adult congenital heart disease (ACHD) patient population are lacking. We conducted a cross-sectional assessment of 4,028 ACHD patients recruited from 24 ACHD-specialized centers in 15 countries across 5 continents to examine the association between physical activity and PHS in a large international cohort of ACHD patients. A linear analog scale of the EuroQol-5D 3 level version and the 12-item Short Form Health Survey-version 2 were used to assess self-reported health status and the Health-Behavior Scale-Congenital Heart Disease was used as a subjective measurement of physical activity type, participation, and level. Correlation analyses and Wilcoxon Rank Sum tests examined bivariate relations between sample characteristics and PHS scores. Then, multivariable models were constructed to understand the impact of physical activity on PHS. Only 30% of our sample achieved recommended physical activity levels. Physically active patients reported better PHS than sedentary patients; however, the amount of physical activity was not associated with PHS. Further statistical analyses demonstrated that specifically sport participation regardless of physical activity level was a predictor of PHS. In conclusion, the majority of ACHD patients across the world are physically inactive. Sport participation appears to be the primary physical activity-related driver of PHS. By promoting sport-related exercise ACHD specialists thus may improve PHS in ACHD patients.