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Clinical Instructor in Department of Medicine, Post-doctoral Research Fellow at Stanford Cardiovascular Institute, PhD Candidate in Epidemiology and Population Health Sciences. Graduate of Stanford Internal Medicine / Global Health Residency / Chief Resident, and Cardiology Fellowship Programs.

Professional interests include epidemiology and health services research focused on heart disease in the developing world and domestic vulnerable populations, utilizing multiple methodologies including epidemiology, health systems modeling, and geospatial data. Other formal training includes bench and translational research background in immunology, cancer biology, and neuroscience. Funded by Spectrum TL1 NIH training grant, completed MS in Epidemiology and Clinical Research in 2018.

Institute Affiliations

  • Member (Postdoc), Cardiovascular Institute

Honors & Awards

  • Alpha Omega Alpha Medical Honor Society, AOA, Stanford University Chapter (2017)
  • Gold Humanism Honor Society, Arnold P. Gold Foundation (2012)
  • TL1 Gold Ribbon Presentation, Association for Clinical and Translational Science (2018)
  • Stanford Cardiovascular Institute Travel Award, Stanford Cardiovascular Institute (2018)
  • Johnson and Johnson Global Health Scholar, Yale/Stanford Johnson & Johnson Global Health Scholars Program (2015)
  • Johnson and Johnson Global Health Scholar, Yale/Stanford Johnson & Johnson Global Health Scholars Program (2014)
  • Asian Pacific American Medical Student Association Global Health Fellowship, Asian Pacific American Medical Student Association (2012)
  • Stanford Medical Scholars Research Fellowship, Stanford University School of Medicine (2009-2011)
  • The John E. Linck III Memorial Graduation Prize, Yale University (2008)
  • Yale College Dean?s Research Fellowship in the Sciences, Yale University (2007)
  • Yale Science and Engineering Research Presentation Travel Prize, Yale University (2007)
  • 1st Place Presentation, Yale Undergraduate Research Symposium in the Biological Sciences, Yale University (2007)
  • The Paul K. and Evalyn Elizabeth Cook Richter Summer Fellowship, Yale University (2007)
  • The Gary Stein Memorial Internship, Yale University (2006)
  • Robert C. Byrd Congressional Honors Scholarship, United States Department of Education (2005)

Professional Affiliations and Activities

  • Faculty Fellow, Stanford Center for Innovation in Global Health (2016 - Present)
  • Representative, Chief Resident's Council, Department of Graduate Medical Education, Stanford University Medical Center (2016 - 2017)
  • Representative,Committee on Residency Reform, Department of Medicine, Stanford University Medical Center (2014 - 2016)
  • Resident Member, American College of Cardiology (2015 - 2017)
  • Resident: Medicine/Global Health, Stanford University Hospital (2013 - 2016)
  • Resident Member, American College of Physicians (2013 - 2016)
  • Member, Stanford Center for Population Health Sciences (2015 - Present)
  • Member, Stanford Society of Physician Scholars (2013 - Present)
  • Member, Young Professionals Chronic Disease Network (2013 - Present)
  • Member, California Medical Association (2013 - Present)
  • Editor-in-Chief, The Stanford Medical Student Clinical Journal (2010 - 2012)

Education & Certifications

  • Fellowship, Stanford Hospitals & Clinics, Cardiology (2021)
  • Chief Resident, Stanford Hospitals & Clinics, Internal Medicine (2017)
  • Residency, Stanford Hospital & Clinics, Internal Medicine (2016)
  • MS, Stanford University, Epidemiology, Clinical Research (2018)
  • MD, Stanford University, Clinical Research, Immunology, Global Health (2013)
  • BS, Yale University, Molecular, Cellular & Developmental Biology (2008)
  • Non-degree Program, American Heart Association (AHA) Ten-Day Seminar on the Epidemiology and Prevention of Cardiovascular Disease, Epidemiology (2017)
  • Non-degree Program, Hasso Plattner Institute of Design at Stanford University, Entrepreneurial Design for Extreme Affordability Program (2012)

Service, Volunteer and Community Work

  • Hepatitis B Clinic Coordinator, Pacific Free Clinic (2009 - 2009)

    - Created protocols, staffed, and managed the Hepatitis B program at Pacific Free Clinic,a student-run health clinic providing medical care for uninsured and underserved populations in the San Jose, CA area.
    - Screened and vaccinated at-risk individuals against Hepatitis B virus, monitored infected patients, and reported epidemiological data to the Santa Clara Department of Public Health.


    San Jose, CA

  • Clinical Volunteer, Arbor Free Clinic (2008 - 2013)

    - Provided medical care at student-run clinic delivering health care for uninsured and underserved populations in the East Palo Alto, CA area.


    Menlo Park, CA

  • Intern, Nyaya Health (2006 - 2008)

    - Developed information sharing infrastructure for nonprofit NGO collaborating with the Nepali government to construct and run a hospital in rural Nepal.
    - Traveled to Kathmandu and Sanfebagar to recruit clinic staff, test telecommunications devices for telemedicine opportunities, and perform administrative duties on behalf of the clinic with UNICEF and the Nepali National Center for STD and AIDS Control.


    Sanfebagar, Nepal

  • Health Educator, Yale University (2004 - 2005)

    Teaching member of initiative to write, teach, and test a health education curriculum for New Haven, CT high school students


    New Haven, CT

  • Community Associate, Stanford University (2009 - 2011)

    Residential advisor in charge of maintaining graduate student safety and wellness through workshops, mentoring, social programming, and mental health initiatives


    Stanford, CA

  • Johnson & Johnson Global Health Scholar, Yale-Stanford Johnson & Johnson Global Health Scholars Program (2015)

    Delivered care for patients and taught medical students and interns at the University Central Hospital of Kigali (CHUK) in Kigali, Rwanda.


    Kigali, Rwanda


  • Andrew Chang, Carey Lee, Pamela Pavkov, Karen Lee, Michael Strasser. "United States Patent Attorney docket number: S11-190 Provisional Patent: ?Low Cost Bubble CPAP Device?", Jun 1, 2011

Personal Interests

Travel, History, Anthroplogy, Writing, Art Appreciation, Cooking, Football, Hiking

Research & Scholarship

Current Research and Scholarly Interests

My research interests center around the epidemiology, environmental determinants, and health services dimensions of heart disease, with an emphasis on vulnerable populations, both international and domestic. Current projects include the development of novel care quality metrics for use in rheumatic heart disease in East Africa, testing of low sodium salt substitutes in South Asia, describing the global patterns of cardiovascular multimorbidity, and assessing the cardiovascular impacts of cyclical climate change-associated major environmental events. Other research interests include cost-effectiveness analysis, health economics, and device/service innovation for low-resource settings.

Current Clinical Interests

  • Cardiovascular Disease
  • Rheumatic Heart Disease
  • Valvular Heart Disease
  • Atrial Fibrillation
  • Anticoagulation
  • Echocardiography

Lab Affiliations

  • Peter Lee, (9/3/2010 - 10/31/2013)


Work Experience

  • Researcher, Stanford University School of Medicine, Department of Hematology (2009 - 2012)

    - Primary Investigator: Peter Lee, M.D.
    - Project: Perturbations of immune cell (dendritic cell and T-cell) spatial distribution within tumor-draining lymph nodes of breast cancer patients
    - Relevant Skills: Human pathology specimen handling, immunohistochemistry, and computational imaging


    Stanford, CA

  • Teaching Assistant, Stanford University School of Medicine (2010 - 2011)

    - Course Directors: Dr. Andrew Connolly and Dr. Julie Theriot
    - Lectured and supervised laboratory exercises for core first-year medical student cell biology and histology class


    Stanford, CA

  • Community Associate, Stanford University Graduate Life Office (2009 - 2011)

    - Residential advisor in charge of maintaining graduate student safety and wellness through workshops, mentoring, social programming, and mental health initiatives


    Stanford, CA

  • Research Assistant, Yale University School of Medicine, Department of Neurobiology (2005 - 2008)

    - Primary Investigator: Gordon M. Shepherd, M.D., Ph.D.
    - Project: Information coding in the murine brain and construction of odotypic maps in the olfactory bulb via localization of pseudorabies virus tracing vector
    - Relevant Skills: Mouse stereotactic microsurgery, fluorescent microscopy, histology, and computational imaging


    New Haven, CT


All Publications

  • The Need to Expand the Framework of Environmental Determinants of Cardiovascular Health From Climate Change to Planetary Health: Trial by Wildfire. Circulation Chang, A. Y., Barry, M., Harrington, R. A. 2021; 143 (21): 2029-2031

    View details for DOI 10.1161/CIRCULATIONAHA.120.051892

    View details for PubMedID 34029138

  • The Impact of Novel Coronavirus COVID-19 on Non-Communicable Disease Patients and Health Systems: A Review. Journal of internal medicine Chang, A. Y., Cullen, M. R., Harrington, R. A., Barry, M. 2020


    Coronavirus Disease 2019 (COVID-19) is an ongoing global pandemic affecting all levels of health systems. This includes the care of patients with noncommunicable diseases (NCDs) who bear a disproportionate burden of both COVID-19 itself and the public health measures enacted to combat it. In this review, we summarize major COVID-19 related considerations for NCD patients and their care providers, focusing on cardiovascular, pulmonary, renal, hematologic, oncologic, traumatic, obstetric/gynecologic, operative, psychiatric, rheumatologic/immunologic, neurologic, gastrointestinal, ophthalmologic, and endocrine disorders. Additionally, we offer a general framework for categorizing the pandemic's disruptions by disease-specific factors, direct health system factors, and indirect health system factors. We also provide references to major NCD medical specialty professional society statements and guidelines on COVID-19. COVID-19 and its control policies have already resulted in major disruptions to the screening, treatment, and surveillance of NCD patients. In addition, it differentially impacts those with pre-existing NCDs and may lead to de novo NCD sequelae. Likely, there will be long-term effects from this pandemic that will continue to affect practitioners and patients in this field for years to come.

    View details for DOI 10.1111/joim.13184

    View details for PubMedID 33020988

  • Outcomes and Care Quality Metrics for Women of Reproductive Age Living With Rheumatic Heart Disease in Uganda. Journal of the American Heart Association Chang, A. Y., Nabbaale, J. n., Okello, E. n., Ssinabulya, I. n., Barry, M. n., Beaton, A. Z., Webel, A. R., Longenecker, C. T. 2020: e015562


    Background Rheumatic heart disease disproportionately affects women of reproductive age, as it increases the risk of cardiovascular complications and death during pregnancy and childbirth. In sub-Saharan Africa, clinical outcomes and adherence to guideline-based therapies are not well characterized for this population. Methods and Results In a retrospective cohort study of the Uganda rheumatic heart disease registry between June 2009 and May 2018, we used multivariable regression and Cox proportional hazards models to compare comorbidities, mortality, anticoagulation use, and treatment cascade metrics among women versus men aged 15 to 44 with clinical rheumatic heart disease. We included 575 women and 252 men with a median age of 27 years. Twenty percent had New York Heart Association Class III-IV heart failure. Among patients who had an indication for anticoagulation, women were less likely than men to receive a prescription of warfarin (66% versus 81%; adjusted odds ratio, 0.37; 95% CI, 0.14-0.96). Retention in care (defined as a clinic visit within the preceding year) was poor among both sexes in this age group (27% for men, 24% for women), but penicillin adherence rates were high among those retained (89% for men, 92% for women). Mortality was higher in men than women (26% versus 19% over a median follow-up of 2.7 years; adjusted hazard ratio, 1.66; 95% CI, 1.18-2.33). Conclusions Compared with men, women of reproductive age with rheumatic heart disease in Uganda have lower rates of appropriate anticoagulant prescription but also lower mortality rates. Retention in care is poor among both men and women in this age range, representing a key target for improvement.

    View details for DOI 10.1161/JAHA.119.015562

    View details for PubMedID 32295465

  • Breast cancer induces systemic immune changes on cytokine signaling in peripheral blood monocytes and lymphocytes. EBioMedicine Wang, L. n., Simons, D. L., Lu, X. n., Tu, T. Y., Avalos, C. n., Chang, A. Y., Dirbas, F. M., Yim, J. H., Waisman, J. n., Lee, P. P. 2020; 52: 102631


    It is increasingly recognized that cancer progression induces systemic immune changes in the host. Alterations in number and function of immune cells have been identified in cancer patients' peripheral blood and lymphoid organs. Recently, we found dysregulated cytokine signaling in peripheral blood T cells from breast cancer (BC) patients, even those with localized disease.We used phosphoflow cytometry to determine the clinical significance of cytokine signaling responsiveness in peripheral blood monocytes from non-metastatic BC patients at diagnosis. We also examined the correlation between cytokine signaling in peripheral monocytes and the number of tumor-infiltrating macrophages in paired breast tumors.Our results show that cytokine (IFN?) signaling may also be dysregulated in peripheral blood monocytes at diagnosis, specifically in BC patients who later relapsed. Some patients exhibited concurrent cytokine signaling defects in monocytes and lymphocytes at diagnosis, which predict the risk of future relapse in two independent cohorts of BC patients. Moreover, IFN? signaling negatively correlates with expression of CSF1R on monocytes, thus modulating their ability to infiltrate into tumors.Our results demonstrate that tumor-induced systemic immune changes are evident in peripheral blood immune cells for both myeloid and lymphoid lineages, and point to cytokine signaling responsiveness as important biomarkers to evaluate the overall immune status of BC patients.This study was supported by the Department of Defense Breast Cancer Research Program (BCRP), The V Foundation, Stand Up to Cancer (SU2C), and Breast Cancer Research Foundation (BCRF).

    View details for DOI 10.1016/j.ebiom.2020.102631

    View details for PubMedID 31981982

  • Cost-effectiveness of Canakinumab for Prevention of Recurrent Cardiovascular Events. JAMA cardiology Sehested, T. S., Bjerre, J., Ku, S., Chang, A., Jahansouz, A., Owens, D. K., Hlatky, M. A., Goldhaber-Fiebert, J. D. 2019


    Importance: In the Canakinumab Anti-inflammatory Thrombosis Outcome Study (CANTOS) trial, the anti-inflammatory monoclonal antibody canakinumab significantly reduced the risk of recurrent cardiovascular events in patients with previous myocardial infarction (MI) and high-sensitivity C-reactive protein (hs-CRP) levels of 2 mg/L or greater.Objective: To estimate the cost-effectiveness of adding canakinumab to standard of care for the secondary prevention of major cardiovascular events over a range of potential prices.Design, Setting, and Participants: A state-transition Markov model was constructed to estimate costs and outcomes over a lifetime horizon by projecting rates of recurrent MI, coronary revascularization, infection, and lung cancer with and without canakinumab treatment. We used a US health care sector perspective, and the base case used the current US market price of canakinumab of $73?000 per year. A hypothetical cohort of patients after MI aged 61 years with an hs-CRP level of 2 mg/L or greater was constructed.Interventions: Canakinumab, 150 mg, administered every 3 months plus standard of care compared with standard of care alone.Main Outcomes and Measures: Lifetime costs and quality-adjusted life-years (QALYs), discounted at 3% annually.Results: Adding canakinumab to standard of care increased life expectancy from 11.31 to 11.36 years, QALYs from 9.37 to 9.50, and costs from $242?000 to $1?074?000, yielding an incremental cost-effectiveness ratio of $6.4 million per QALY gained. The price would have to be reduced by more than 98% (to $1150 per year or less) to meet the $100?000 per QALY willingness-to-pay threshold. These results were generally robust across alternative assumptions, eg, substantially lower health-related quality of life after recurrent cardiovascular events, lower infection rates while receiving canakinumab, and reduced all-cause mortality while receiving canakinumab. Including a potential beneficial effect of canakinumab on lung cancer incidence improved the incremental cost-effectiveness ratio to $3.5 million per QALY gained. A strategy of continuing canakinumab selectively in patients with reduction in hs-CRP levels to less than 2 mg/L would have a cost-effectiveness ratio of $819?000 per QALY gained.Conclusions and Relevance: Canakinumab is not cost-effective at current US prices for prevention of recurrent cardiovascular events in patients with a prior MI. Substantial price reductions would be needed for canakinumab to be considered cost-effective.

    View details for PubMedID 30649147

  • Interventions to Reduce Ethnic and Racial Disparities in Dyslipidemia Management. Current treatment options in cardiovascular medicine Chang, A. Y., Abou-Arraj, N. E., Rodriguez, F. n. 2019; 21 (5): 24


    Race and ethnicity are associated with disparities in risk assessment, screening, patient awareness, treatment, and control of dyslipidemia and can contribute to worsened cardiovascular outcomes. This review summarizes these gaps in care and highlights recent interventions aimed at reducing them.Disparities in dyslipidemia diagnosis and treatment are well documented among certain racial and ethnic minority groups. Less is known about dyslipidemia among Hispanics, Asians, and Native Americans/Pacific Islanders, who have significant heterogeneity in cardiovascular risk and outcomes. Programs to reduce inequalities have focused on targeted risk assessment, improved screening practices, statin adherence-enhancing policies, culturally inclusive risk factor modification campaigns, and multidisciplinary treatment teams, with variable success. Interventions to reduce racial/ethnic disparities in dyslipidemia are important at all phases of care. Nevertheless, initiatives concentrating on single elements of the lipid treatment cascade were generally less effective at improving clinical endpoints than those that comprehensively addressed multiple phases. Moreover, there was a disproportionately greater number of published studies analyzing patient-facing lifestyle-based risk factor modifications than other types of interventions. Future investigations should focus on understudied populations such as disaggregated Hispanic, Asian, and Native American populations. Additionally, innovative strategies utilizing information technology and provider-facing programs are needed.

    View details for PubMedID 31065884

  • Association of Healthcare Plan with Atrial Fibrillation Prescription Patterns. Clinical cardiology Chang, A. Y., Askari, M. n., Fan, J. n., Heidenreich, P. A., Ho, P. M., Mahaffey, K. W., Ullal, A. J., Perino, A. C., Turakhia, M. P. 2018


    Atrial fibrillation (AF) is treated by many types of physician specialists, including primary care physicians (PCPs). Health plans have different policies for how patients encounter these providers, and these may affect selection of AF treatment strategy.We hypothesized that healthcare plans with PCP-gatekeeping to specialist access may be associated with different pharmacologic treatments for AF.We performed a retrospective cohort study using a commercial pharmaceutical claims database. We utilized logistic regression models to compare odds of prescription of oral anticoagulant (OAC), non-vitamin K-dependent oral anticoagulant (NOAC), rate control, and rhythm control medications used to treat AF between patients with PCP-gated healthcare plans (e.g. HMO, EPO, POS) and patients with non-PCP-gated healthcare plans (e.g. PPO, CHDP, HDHP, Comprehensive) between 2007 and 2012. We also calculated median time to receipt of therapy within 90 days of index AF diagnosis.We found similar odds of OAC prescription at 90 days following new AF diagnosis in patients with PCP-gated plans compared to those with non-PCP-gated plans (OR: OAC 1.01, p=0.84; warfarin 1.05, p=0.08). Relative odds were similar for rate control (1.17, p<0.01) and rhythm control agents (0.93, p=0.03). However, PCP-gated plan patients had slightly lower likelihood of being prescribed NOACs (0.82, p=0.001) than non-gated plan patients. Elapsed time until receipt of medication was similar between PCP-gated and non-gated groups across drug classes.Pharmaceutical claims data do not suggest that PCP-gatekeeping by healthcare plans is a structural barrier to AF therapy, although it was associated with lower use of NOACs.

    View details for PubMedID 30098034

  • Patient and facility variation in costs of catheter ablation for atrial fibrillation. Journal of cardiovascular electrophysiology Perino, A. C., Fan, J. n., Schmitt, S. n., Kaiser, D. W., Heidenreich, P. A., Narayan, S. M., Wang, P. J., Chang, A. Y., Turakhia, M. P. 2018


    Cost-effectiveness or value of cardiovascular therapies may be undermined by unwarranted cost variation, particularly for heterogeneous procedures such as catheter ablation for atrial fibrillation (AF). We sought to characterize cost variation of AF ablation in the U.S. health care system and the relationship between cost and outcomes.We performed a retrospective cohort study using data from the MarketScan® commercial claims and Medicare supplemental databases including patients who received an AF ablation from 2007 through 2011. We aggregated encounter cost, reflecting total payments received for the encounter, to the facility level to calculate median facility cost. We classified procedures as outpatient or inpatient and assessed for association between cost and 30-day and one-year outcomes. The analysis cohort included 9,415 AF ablations (59±11 years; 28% female; 52% outpatient) occurring at 327 facilities, with large cost variation across facilities (median: $25,100; 25th percentile: $18,900, 75th percentile: $35,600, 95th percentile: $57,800). Among outpatient procedures, there was reduced health care utilization in higher cost quintiles with reductions in rehospitalization at 30-days (Quintile 1: 16.1%, Quintile 5: 8.8%, p < 0.001) and one-year (Quintile 1: 34.8%, Quintile 5: 25.6%, p < 0.001), which remained significant in multivariate analysis.Although median costs of AF ablation are below amounts used in prior cost-effectiveness studies that demonstrated good value, large facility variation in cost suggests opportunities for cost reduction. However, for outpatient encounters, association of cost to modestly improved outcomes suggests cost containment strategies could have variable effects. This article is protected by copyright. All rights reserved.

    View details for PubMedID 29864193

  • Motivations of women in Uganda living with rheumatic heart disease: A mixed methods study of experiences in stigma, childbearing, anticoagulation, and contraception. PloS one Chang, A. Y., Nabbaale, J. n., Nalubwama, H. n., Okello, E. n., Ssinabulya, I. n., Longenecker, C. T., Webel, A. R. 2018; 13 (3): e0194030


    Rheumatic heart disease (RHD) is a leading cause of premature mortality in low- and middle-income countries (LMICs). Women of reproductive age are a unique and vulnerable group of RHD patients, due to increased risk of cardiovascular complications and death during pregnancy. Yet, less than 5% of women of childbearing age with RHD in LMICs use contraceptives, and one in five pregnant women with RHD take warfarin despite known teratogenicity. It is unclear whether this suboptimal contraception and anticoagulant use during pregnancy is due to lack of health system resources, limited health literacy, or social pressure to bear children.We conducted a mixed methods study of 75 women living with RHD in Uganda. Questionnaires were administered to 50 patients. Transcripts from three focus groups with 25 participants were analyzed using qualitative description methodology.Several themes emerged from the focus groups, including pregnancy as a calculated risk; misconceptions about side-effects of contraceptives and anticoagulation; reproductive decision-making control by male partners, in-laws, or physicians; abandonment of patients by male partners; and considerable stigma against heart disease patients for both their reproductive and financial limitations (often worse than that directed against HIV patients). All questionnaire respondents were told by physicians that their hearts were not strong enough to support a pregnancy. Only 14% used contraception while taking warfarin. All participants felt that society would look poorly on a woman who cannot have children due to a heart condition.To our knowledge, this is the first qualitative study of female RHD patients and their attitudes toward cardiovascular disorders and reproduction. Our results suggest that health programs targeting heart disease in LMICs must pay special attention to the needs of women of childbearing age. There are opportunities for improved family/societal education programs and community engagement, leading to better outcomes and patient empowerment.

    View details for PubMedID 29590159

    View details for PubMedCentralID PMC5874006

  • IL6 Signaling in Peripheral Blood T Cells Predicts Clinical Outcome in Breast Cancer. Cancer research Wang, L., Miyahira, A. K., Simons, D. L., Lu, X., Chang, A. Y., Wang, C., Suni, M. A., Maino, V. C., Dirbas, F. M., Yim, J., Waisman, J., Lee, P. P. 2017; 77 (5): 1119-1126


    IL6 is a pleiotropic cytokine with both pro- and anti-inflammatory properties, which acts directly on cancer cells to promote their survival and proliferation. Elevated serum IL6 levels negatively correlate with survival of cancer patients, which is generally attributed to the direct effects of IL6 on cancer cells. How IL6 modulates the host immune response in cancer patients is unclear. Here, we show the IL6 signaling response in peripheral blood T cells is impaired in breast cancer patients and is associated with blunted Th17 differentiation. The mechanism identified involved downregulation of gp130 and IL6R? in breast cancer patients and was independent of plasma IL6 levels. Importantly, defective IL6 signaling in peripheral blood T cells at diagnosis correlated with worse relapse-free survival. These results indicate that intact IL6 signaling in T cells is important for controlling cancer progression. Furthermore, they highlight a potential for IL6 signaling response in peripheral blood T cells at diagnosis as a predictive biomarker for clinical outcome of breast cancer patients. Cancer Res; 77(5); 1119-26. ©2016 AACR.

    View details for DOI 10.1158/0008-5472.CAN-16-1373

    View details for PubMedID 27879265

  • Regenerative Medicine: Potential Mechanisms of Cardiac Recovery in Takotsubo Cardiomyopathy. Current treatment options in cardiovascular medicine Chang, A. Y., Kittle, J. T., Wu, S. M. 2016; 18 (3): 20-?


    Takotsubo cardiomyopathy is an increasingly reported cause of acute chest pain and acute heart failure and is often associated with significant hemodynamic compromise. The illness is remarkable for the reversibility in systolic dysfunction seen in the disease course. While the pathophysiology of takotsubo syndrome is not completely elucidated, research suggests the presence of a cytoprotective process that allows the myocardium to recover following the inciting insult. Here, we summarize molecular and histologic studies exploring the response to injury in takotsubo disease and provide some discussion on how they may contribute to further investigations in cardiac recovery and regeneration.

    View details for DOI 10.1007/s11936-016-0443-0

    View details for PubMedID 26874708

  • The Global Health Implications of e-Cigarettes. JAMA Chang, A. Y., Barry, M. 2015; 314 (7): 663-664

    View details for DOI 10.1001/jama.2015.8676

    View details for PubMedID 26284714

  • Evaluating the Cost-effectiveness of Catheter Ablation of Atrial Fibrillation. Arrhythmia & electrophysiology review Chang, A. Y., Kaiser, D., Ullal, A., Perino, A. C., Heidenreich, P. A., Turakhia, M. P. 2014; 3 (3): 177-183


    Atrial fibrillation (AF) is one of the most common cardiac conditions treated in primary care and specialty cardiology settings, and is associated with considerable morbidity, mortality and cost. Catheter ablation, typically by electrically isolating the pulmonary veins and surrounding tissue, is more effective at maintaining sinus rhythm than conventional antiarrhythmic drug therapy and is now recommended as first-line therapy. From a value standpoint, the cost-effectiveness of ablation must incorporate the upfront procedural costs and risks with the benefits of longer term improvements in quality of life (QOL) and healthcare utilisation. Here, we present a primer on cost-effectiveness analysis (CEA), review the data on cost-effectiveness of AF ablation and outline key areas for further investigation.

    View details for DOI 10.15420/aer.2014.3.3.177

    View details for PubMedID 26835088

  • Trial of Zolpidem, Eszopiclone, and Other GABA Agonists in a Patient with Progressive Supranuclear Palsy Case Reports in Medicine Chang, A. Y., Weirich, E. 2014; 2014: 5
  • Spatial organization of dendritic cells within tumor draining lymph nodes impacts clinical outcome in breast cancer patients JOURNAL OF TRANSLATIONAL MEDICINE Chang, A. Y., Bhattacharya, N., Mu, J., Setiadi, A. F., Carcamo-Cavazos, V., Lee, G. H., Simons, D. L., Yadegarynia, S., Hemati, K., Kapelner, A., Ming, Z., Krag, D. N., Schwartz, E. J., Chen, D. Z., Lee, P. P. 2013; 11


    Dendritic cells (DCs) are important mediators of anti-tumor immune responses. We hypothesized that an in-depth analysis of dendritic cells and their spatial relationships to each other as well as to other immune cells within tumor draining lymph nodes (TDLNs) could provide a better understanding of immune function and dysregulation in cancer.We analyzed immune cells within TDLNs from 59 breast cancer patients with at least 5 years of clinical follow-up using immunohistochemical staining with a novel quantitative image analysis system. We developed algorithms to analyze spatial distribution patterns of immune cells in cancer versus healthy intra-mammary lymph nodes (HLNs) to derive information about possible mechanisms underlying immune-dysregulation in breast cancer. We used the non-parametric Mann-Whitney test for inter-group comparisons, Wilcoxon Matched-Pairs Signed Ranks test for intra-group comparisons and log-rank (Mantel-Cox) test for Kaplan Maier analyses.Degree of clustering of DCs (in terms of spatial proximity of the cells to each other) was reduced in TDLNs compared to HLNs. While there were more numerous DC clusters in TDLNs compared to HLNs,DC clusters within TDLNs tended to have fewer member DCs and also consisted of fewer cells displaying the DC maturity marker CD83. The average number of T cells within a standardized radius of a clustered DC was increased compared to that of an unclustered DC, suggesting that DC clustering was associated with T cell interaction. Furthermore, the number of T cells within the radius of a clustered DC was reduced in tumor-positive TDLNs compared to HLNs. Importantly, clinical outcome analysis revealed that DC clustering in tumor-positive TDLNs correlated with the duration of disease-free survival in breast cancer patients.These findings are the first to describe the spatial organization of DCs within TDLNs and their association with survival outcome. In addition, we characterized specific changes in number, size, maturity, and T cell co-localization of such clusters. Strategies to enhance DC function in-vivo, including maturation and clustering, may provide additional tools for developing more efficacious DC cancer vaccines.

    View details for DOI 10.1186/1479-5876-11-242

    View details for Web of Science ID 000326447100001

    View details for PubMedID 24088396

    View details for PubMedCentralID PMC3852260

  • Center-surround vs. distance-independent lateral connectivity in the olfactory bulb FRONTIERS IN NEURAL CIRCUITS Kim, D. H., Chang, A. Y., McTavish, T. S., Pateland, H. K., Willhite, D. C. 2012; 6


    Lateral neuronal interactions are known to play important roles in sensory information processing. A center-on surround-off local circuit arrangement has been shown to play a role in mediating contrast enhancement in the visual, auditory, and somatosensory systems. The lateral connectivity and the influence of those connections have been less clear for the olfactory system. A critical question is whether the synaptic connections between the primary projection neurons, mitral and tufted (M/T) cells, and their main inhibitory interneurons, the granule cells (GCs), can support a center-surround motif. Here, we study this question by injecting a "center" in the glomerular layer of the olfactory bulb (OB) with a marker of synaptic connectivity, the pseudorabies virus (PRV), then examines the distribution of labeling in the "surround" of GCs. We use a novel method to score the degree to which the data fits a center-surround model vs. distance-independent connectivity. Data from 22 injections show that M/T cells generally form lateral connections with GCs in patterns that lie between the two extremes.

    View details for DOI 10.3389/fncir.2012.00034

    View details for Web of Science ID 000304625700001

    View details for PubMedID 22666190

    View details for PubMedCentralID PMC3364486

  • Learning to live together: harnessing regulatory T cells to induce organ transplant tolerance. Yale journal of biology and medicine Chang, A. Y., Bhattacharya, N. 2011; 84 (4): 345-351


    The discovery of immune cells with regulatory effects has created considerable excitement for their potential use in inducing tolerance to transplanted tissues. Despite the fact that these cells possess essential functions in vivo, attempts to translate them into effective clinical therapies has proved challenging due to a number of unanticipated complexities in their behavior. This article provides a broad summary of research done to understand the largest of the regulatory cell subtypes, namely CD4+Foxp3+ Regulatory T cells (T(Regs)). Special attention will be paid to current and future difficulties in using T(Regs) clinically, as well as room for improvement and innovation in this field.

    View details for PubMedID 22180672

  • Lateral connectivity in the olfactory bulb is sparse and segregated FRONTIERS IN NEURAL CIRCUITS Kim, D. H., Phillips, M. E., Chang, A. Y., Patel, H. K., Nguyen, K. T., Willhite, D. C. 2011; 5


    Lateral connections in the olfactory bulb were previously thought to be organized for center-surround inhibition. However, recent anatomical and physiological studies showed sparse and distributed interactions of inhibitory granule cells (GCs) which tended to be organized in columnar clusters. Little is known about how these distributed clusters are interconnected. In this study, we use transsynaptic tracing viruses bearing green or red fluorescent proteins to further elucidate mitral- and tufted-to-GC connectivity. Separate sites in the glomerular layer were injected with each virus. Columns with labeling from both viruses after transsynaptic spread show sparse red or green GCs which tended to be segregated. However, there was a higher incidence of co-labeled cells than chance would predict. Similar segregation of labeling is observed from dual injections into olfactory cortex. Collectively, these results suggest that neighboring mitral and tufted cells receive inhibitory inputs from segregated subsets of GCs, enabling inhibition of a center by specific and discontinuous lateral elements.

    View details for DOI 10.3389/fncir.2011.00005

    View details for Web of Science ID 000290153700001

    View details for PubMedID 21559072

  • Hydrophilic Graft Modification of a Commercial Crystalline Polyolefin J. Polym. Sci. Part A: Polym. Chem. Jihoon Shin, Andrew Y. Chang, Lacie V. Brownell, Ira O. Racoma, Coreen H. Ozawa, Ho-Yong Chung, Shufu Peng, Chulsung Bae 2008; 46: 3533-3545
  • Regioselective functionalization of high-molecular-weight crystalline polyolefins via C-H activation of methyl side group Polymer Preprints Hoyong Chung, Andrew Y. Chang, Ira O. Racoma, Coreen H. Ozawa, Chulsung Bae 2006; 47: 247-248

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