A Letter from the Editorial Board

Dear readers, After a year of developments, we are proud to present the Spring 2017 Columbia Undergraduate Science Journal. The current edition of the journal features topics from all over the natural sciences. This year, our main focus regarding the Journal was to extend the reach of the journal to universities all over the world. As the CUSJ’s mission is to encourage students to involve themselves in scientific discovery, we saw no need to restrict our scope to only Columbia University. We received submissions from diverse areas such as biochemistry, astrophysics, and electrical engineering. Our team also published the second issue of the Columbia Junior Science Journal, a journal meant to introduce high school researchers to the world of research publication. After making changes to the previous Columbia Research Scholars Journal to better reflect the mission of the journal, we were proud to publish many of the incredible submissions sent in from high schoolers from around the United States, and invite several of them to our annual Spring Symposium. In addition to producing the two research journals for high school and college students, the CUSJ also seeks to foster the undergraduate research community at Columbia University. This year, we worked hard to further this goal by hosting several events on campus. In the Fall, the CUSJ hosted an event to assist undergraduate students in the process of soliciting a research position. In the Spring, the CUSJ hosted Dr. George Yancopoulos, founder of Regeneron and chief scientific officer, and held the annual symposium. This year’s the CUSJ Spring Research Symposium involved a welcome address from Dr. Gasperov, the undergraduate science research adviser at Columbia University, as well as a poster session where students presented on their research. The Awards of Excellence this year went to Nicholas Page from Rutgers University and Sarah Lundell from Fordham University. This Spring, the CUSJ also established the CUSJ Colloquium, a bi-weekly undergraduate speaker series where students from an array of scientific disciplines presented their research in a comfortable peer setting. Students discussed topics in research subjects including two-dimensional materials, exoplanets, biofilms, viral binding, ophthalmology, and photosynthetic origins of life. Our publications, the CUSJ and CJSJ, and the events we hosted this year could not have happened without the hard work of our editorial team and the assistance of our faculty board and advisors. Natalie Kolba, Editor-in-Chief Osman Moneer, Presiden

Preoperative Atrial Fibrillation/Flutter Impact on Risk-Adjusted Repeat Aortic Intervention Patients[PROTOCOL]

Aim: Impacts of pre-operative atrial fibrillation or flutter (AF/AFL) upon repeat aortic valve replacement (r-AVR) patients’ risk-adjusted short-term outcomes is unknown.Methods: From 2005-2018, New York State AF/AFL versus non-AF/AFL adults’ risk-adjusted r-AVR outcomes were compared. Primary endpoints included the Society of Thoracic Surgeons’ 30-day operative mortality or major morbidity (MM) composite and 30-day readmission (READMIT); the MM sub-components were secondary endpoints. Multivariable logistic regression models evaluated AF/AFL impact upon these endpoints while holding other factors constant.Results: Of 36,783 adults initially undergoing aortic valve replacement, 334 subsequently underwent r-AVR. Within this r-AVR group, 42.4% of repeat surgical (r-SAVR) patients had AF/AFL; 50.4% of repeat transcatheter (viv-TAVR) patients had AF/AFL. R-SAVR AF/AFL patients were older and had more comorbidities than those without AF/AFL. Viv-TAVR AF/AFL patients were similar to those without AF/AFL except for lower rates of chronic obstructive pulmonary disease. Comparing risk-adjusted r-AVR outcomes, AF/AFL did not impact MM [odds ratio (OR), 95% confidence interval (CI): 1.23, 0.66-2.28, P = 0.512] or READMIT (OR, 95%CI: 1.15, 0.60-2.19, P = 0.681). Black race (OR, 95%CI: 2.89, 1.01-8.32, P = 0.049) and Elixhauser mortality score (OR, 95%CI: 1.07, 1.04-1.10, P < 0.0001) predicted MM risk. Cerebrovascular disease (OR, 95%CI: 2.54, 1.23-5.25, P = 0.012) predicted READMIT risk, while viv-TAVR was protective compared to r-SAVR (OR, 95%CI: 0.44, 0.21-0.91, P = 0.027).Conclusion: AF/AFL was not associated with risk-adjusted short-term r-AVR outcomes. Black race, Elixhauser mortality score, and cerebrovascular disease predicted adverse outcomes

Predictors and risk-adjusted outcomes of new-onset postoperative atrial fibrillation in repeat surgical and valve-in-valve transcatheter aortic valve replacement

Aim: New-onset postoperative atrial fibrillation/flutter (POAF/AFL) complications have not been well studied for repeat aortic valve replacements (r-AVR); this study identified risk factors predisposing to POAF/AFL and POAF/AFL’s effect upon risk-adjusted outcomes.Methods: Using New York State’s Statewide Planning and Research Cooperative System records (2005-2018), multivariable forward selection models identified risks predictive of POAF/AFL. To identify POAF/AFL’s impact upon risk-adjusted mortality/morbidity (MM) and 30-day readmission (READMIT), forward selection logistic regression models applied Firth bias correction to address data sparsity.Results: Of the 242 r-AVR patients, 147 underwent repeat surgical aortic valve replacements (r-SAVR) and 95 underwent valve-in-valve transcatheter aortic valve replacements (ViV-TAVR); 39.46% of r-SAVR and 43.16% of ViV-TAVR patients had POAF/AFL. R-SAVR patients with POAF/AFL were older (69.7 ± 11.1 vs. 56.7 ± 13.2 years, P < 0.01) compared to R-SAVR patients without POAF/AFL. Multivariable models identified an enhanced POAF/AFL risk for elderly (OR: 1.05, 95%CI: 1.03-1.07, P < 0.01) and cerebral vascular disease (OR: 2.18, 95%CI: 1.05-4.55, P = 0.04) patients. Bivariately, POAF/AFL was associated with READMIT, but not MM. Correspondingly, multivariable models found POAF/AFL increased READMIT (OR: 3.12, 95%CI: 1.46-6.65, P < 0.01), but not MM. However, black race (OR: 4.97, 95%CI: 1.61-15.37, P < 0.01) and Elixhauser score (OR: 1.05, 95%CI: 1.02-1.08, P < 0.01) increased risk for MM.Conclusion: More common in older and cerebrovascular disease patients, 41% of r-AVR patients with POAF/AFL had increased READMIT risk; thus, future investigations should focus on improving POAF/AF r-AVR patients’ post-discharge continuity of care