Bio

Clinical Focus


  • Cardiovascular Disease

Academic Appointments


Honors & Awards


  • Sarnoff Cardiovascular Research Fellowship, Sarnoff Cardiovascular Foundation (2009-2011)
  • Gertrude M and Ezra M. Eisen Prize for Cardiovascular Research, University of Pennsylvania (2011)
  • ASPIRE Transthyretin Amyloidosis Competitive Research Grant, Pfizer (2017)
  • Carl Storm Underrepresented Minority Fellowship, Gordon Research Conference (2017)
  • Thomas W. Smith Fellowship in Heart Failure, Brigham and Women?s Hospital (2017)
  • Loan Repayment Program Award, National Institutes of Health (2017-2019, 2019-2020)
  • Presidential Travel Award, International Society of Amyloidosis (2018)
  • Fellow, American College of Cardiology (2019)
  • Harold Amos Medical Faculty Development Program Award, American Heart Association (2019)

Boards, Advisory Committees, Professional Organizations


  • Member, Alumni Committee, Sarnoff Cardiovascular Research Foundation (2017 - 2019)
  • Co-Chair, Diversity and Inclusion Committee, California Chapter, American College of Cardiology (2018 - Present)
  • Editorial Board, Circulation Research (2019 - Present)

Professional Education


  • Fellowship:Stanford University Advanced Heart Failure and Transplant Fellowship (2019) CA
  • Fellowship:Brigham and Women's Hospital Cardiovascular Disease Fellowship (2018) MA
  • Board Certification: Cardiovascular Disease, American Board of Internal Medicine (2017)
  • Board Certification: Internal Medicine, American Board of Internal Medicine (2014)
  • Residency:Johns Hopkins Hospital Internal Medicine Residency (2014) MD
  • Medical Education:Perelman School of Medicine University of Pennsylvania (2011) PA
  • Board Certification, American Board of Internal Medicine, Cardiovascular Disease (2017)
  • Board Certification, American Board of Internal Medicine, Internal Medicine (2014)
  • Fellowship, Stanford Health Care, Advanced Heart Failure and Transplant Cardiology (2019)
  • Fellowship, Brigham and Women's Hospital, Cardiovascular Medicine (2017)
  • Residency, Johns Hopkins Hospital, Internal Medicine (2014)
  • M.D., University of Pennsylvania (2011)
  • B.S., Yale University, Molecular Biophysics and Biochemistry (2006)

Publications

All Publications


  • Emerging Therapies for Transthyretin Cardiac Amyloidosis. Current treatment options in cardiovascular medicine Alexander, K. M., Evangelisti, A., Witteles, R. M. 2019; 21 (8): 40

    Abstract

    Transthyretin cardiac amyloidosis is an underdiagnosed, undertreated disease which is associated with significant morbidity and mortality. This review will discuss the recent advancements in novel therapies for transthyretin amyloidosis.In recent phase 3 clinical trials, transthyretin stabilizers (tafamidis) and transthyretin silencers (patisiran and inotersen) have proven to be effective therapies for various forms of transthyretin amyloidosis. Understanding the recent and upcoming clinical trials for transthyretin amyloidosis will be important for improving the management of this challenging disease.

    View details for DOI 10.1007/s11936-019-0743-2

    View details for PubMedID 31309347

  • Trends and causes of hospitalizations in patients with amyloidosis. Amyloid : the international journal of experimental and clinical investigation : the official journal of the International Society of Amyloidosis Patil, N., Arora, S., Qamar, A., Strassle, P. D., Alexander, K. M., Fatima, A., Maurer, M. S., Grodin, J. L., Pandey, A. 2019: 1?2

    View details for DOI 10.1080/13506129.2019.1618261

    View details for PubMedID 31172802

  • True, true unrelated? Coexistence of Waldenstrom's macroglobulinemia and cardiac transthyretin Amyloidosis. Haematologica Singh, A., Geller, H. I., Alexander, K. M., Padera, R. F., Mitchell, R. N., Dorbala, S., Castillo, J. J., Falk, R. H. 2018

    View details for PubMedID 29674499

  • Mortality from Heart Failure and Dementia in the United States: CDC WONDER 1999-2016. Journal of cardiac failure Vuong, J. T., Jacob, S. A., Alexander, K. M., Singh, A., Liao, R., Desai, A. S., Dorbala, S. 2018

    Abstract

    Heart failure and dementia are diseases of the elderly that result in billions of dollars in annual healthcare expenditure. With the aging of the United States population, and increasing evidence of shared risk factors, there is a need to understand the conditions' shared contributions to nationwide mortality. The objectives of our study are to estimate the burden of mortality from heart failure and dementia and characterize the demographics of affected individuals.This is a retrospective study using National Vital Statistics Data from 1999-2016 provided by the Centers for Disease Control and ICD-10 codes for heart failure and dementia defined by the Medicare Chronic Conditions Data Warehouse. From 1999 to 2016, deaths contributed by heart failure and dementia totaled 214,706 and comprised 4.00% of all heart failure deaths and 9.04% of all dementia deaths. Women were more affected than men, with higher age-adjusted mortality rates (per 1,000,000 person-years): 38.67, 95% CI: 38.47-38.87 vs. 32.90, 95% CI: 32.65-33.15, p<0.001. Whites were affected more than Blacks, with age-adjusted mortality rates (per 1,000,000 person-years): 38.00, 95% CI: 37.83-38.16 vs. 31.06, 95% CI: 30.54-31.59, p<0.001. However, under the age of 65 years, higher crude mortality rates (per 1,000,000 person-years) were reported in men (0.20, 95% CI 0.18-0.22) compared with women (0.15, 95% CI 0.13-0.16, p<0.001).This study provides insight into temporal trends and nationwide mortality rates reported for heart failure and dementia. Our results suggest a disproportionate burden on populations over 85 years, Whites, and women.

    View details for PubMedID 30471348

  • Stage A Heart Failure: Identification and Management of Heart Failure Risk Factors Encyclopedia of Cardiovascular Research and Medicine Alexander, K. M., Nayor, M. 2018: 446?455
  • Randomized Evaluation of Heart Failure With Preserved Ejection Fraction Patients With Acute Heart Failure and Dopamine: The ROPA-DOP Trial. JACC. Heart failure Sharma, K., Vaishnav, J., Kalathiya, R., Hu, J. R., Miller, J., Shah, N., Hill, T., Sharp, M., Tsao, A., Alexander, K. M., Gupta, R., Montemayor, K., Kovell, L., Chasler, J. E., Lee, Y. J., Fine, D. M., Kass, D. A., Weiss, R. G., Thiemann, D. R., Ndumele, C. E., Schulman, S. P., Russell, S. D. 2018

    Abstract

    This study sought to compare a continuous infusion diuretic strategy versus an intermittent bolus diuretic strategy, with the addition of low-dose dopamine (3 ?g/kg/min) in the treatment of hospitalized patients with heart failure with preserved ejection fraction (HFpEF).HFpEF patients are susceptible to development of worsening renal function (WRF) when hospitalized with acute heart failure; however, inpatient treatment strategies to achieve safe and effective diuresis in HFpEF patients have not been studied to date.In a prospective, randomized, clinical trial, 90 HFpEF patients hospitalized with acute heart failure were randomized within 24 h of admission to 1 of 4 treatments: 1) intravenous bolus furosemide administered every 12 h; 2) continuous infusion furosemide; 3) intermittent bolus furosemide with low-dose dopamine; and 4) continuous infusion furosemide with low-dose dopamine. The primary endpoint was percent change in creatinine from baseline to 72 h. Linear and logistic regression analyses with tests for interactions between diuretic and dopamine strategies were performed.Compared to intermittent bolus strategy, the continuous infusion strategy was associated with higher percent increase in creatinine (continuous infusion: 16.01%; 95% confidence interval [CI]: 8.58% to 23.45% vs. intermittent bolus: 4.62%; 95% CI: -1.15% to 10.39%; p = 0.02). Low-dose dopamine had no significant effect on percent change in creatinine (low-dose dopamine: 12.79%; 95% CI: 5.66% to 19.92%, vs. no-dopamine: 8.03%; 95% CI: 1.44% to 14.62%; p = 0.33). Continuous infusion was also associated with greater risk of WRF than intermittent bolus (odds ratio [OR]: 4.32; 95% CI: 1.26 to 14.74; p = 0.02); no differences in WRF risk were seen with low-dose dopamine. No significant interaction was seen between diuretic strategy and low-dose dopamine (p > 0.10).In HFpEF patients hospitalized with acute heart failure, low-dose dopamine had no significant impact on renal function, and a continuous infusion diuretic strategy was associated with renal impairment. (Diuretics and Dopamine in Heart Failure With Preserved Ejection Fraction [ROPA-DOP]; NCT01901809).

    View details for DOI 10.1016/j.jchf.2018.04.008

    View details for PubMedID 30098962

  • Geographic Disparities in Reported US Amyloidosis Mortality From 1979 to 2015: Potential Underdetection of Cardiac Amyloidosis. JAMA cardiology Alexander, K. M., Orav, J., Singh, A., Jacob, S. A., Menon, A., Padera, R. F., Kijewski, M. F., Liao, R., Di Carli, M. F., Laubach, J. P., Falk, R. H., Dorbala, S. 2018

    Abstract

    Cardiac amyloidosis is an underdiagnosed disease and is highly fatal when untreated. Early diagnosis and treatment with the emerging novel therapies significantly improve survival. A comprehensive analysis of amyloidosis-related mortality is critical to appreciate the nature and distribution of underdiagnosis and improve disease detection.To evaluate the temporal and regional trends in age-adjusted amyloidosis-related mortality among men and women of various races/ethnicities in the United States.In this observational cohort study, death certificate information from the Centers for Disease Control and Prevention's Wide-ranging ONline Data for Epidemiologic Research database and the National Vital Statistics System from 1979 to 2015 was analyzed. A total of 30?764 individuals in the United States with amyloidosis listed as the underlying cause of death and 26?591 individuals with amyloidosis listed as a contributing cause of death were analyzed.Region of residence.Age-adjusted mortality rate from amyloidosis per 1?000?000 population stratified by year, sex, race/ethnicity, and state and county of residence.Of the 30?764 individuals with amyloidosis listed as the underlying cause of death, 17?421 (56.6%) were men and 27?312 (88.8%) were 55 years or older. From 1979 to 2015, the reported overall mean age-adjusted mortality rate from amyloidosis as the underlying cause of death doubled from 1.77 to 3.96 per 1?000?000 population (2.32 to 5.43 in men and 1.35 to 2.80 in women). Black men had the highest mortality rate (12.36 per 1?000?000), followed by black women (6.48 per 1?000?000). Amyloidosis contributed to age-adjusted mortality rates as high as 31.73 per 1?000?000 in certain counties. Most southern states reported the lowest US mortality rates despite having the highest proportions of black individuals.The increased reported mortality over time and in proximity to amyloidosis centers more likely reflects an overall increase in disease diagnosis rather than increased lethality. The reported amyloidosis mortality is highly variable in different US regions. The lack of higher reported mortality rates in states with a greater proportion of black residents suggests underdiagnosis of amyloidosis, including cardiac forms of the disease, in many areas of the United States. Better understanding of the determinants of geographic and racial disparity in the reporting of amyloidosis deaths are warranted.

    View details for PubMedID 30046835

  • Association Between Ruptured Distal Biceps Tendon and Wild-Type Transthyretin Cardiac Amyloidosis. JAMA Geller, H. I., Singh, A., Alexander, K. M., Mirto, T. M., Falk, R. H. 2017; 318 (10): 962?63

    View details for PubMedID 28898370

    View details for PubMedCentralID PMC5818850

  • Novel pharmacotherapies for cardiac amyloidosis. Pharmacology & therapeutics Alexander, K. M., Singh, A., Falk, R. H. 2017; 180: 129?38

    Abstract

    Amyloidosis refers to a range of protein misfolding disorders that can cause organ dysfunction through progressive fibril deposition. Cardiac involvement often leads to significant morbidity and mortality and increasingly has been recognized as an important cause of heart failure. The two main forms of cardiac amyloidosis, light chain (AL) and transthyretin (ATTR) amyloidosis, have distinct mechanisms of pathogenesis. Recent insights have led to the development of novel pharmacotherapies with the potential to significantly impact each disease. This review will summarize the preclinical and clinical data for these emerging treatments for AL and ATTR amyloidosis.

    View details for PubMedID 28648829

    View details for PubMedCentralID PMC5832446

  • Phosphorylation of Src by phosphoinositide 3-kinase regulates beta-adrenergic receptor-mediated EGFR transactivation. Cellular signalling Watson, L. J., Alexander, K. M., Mohan, M. L., Bowman, A. L., Mangmool, S., Xiao, K., Naga Prasad, S. V., Rockman, H. A. 2016; 28 (10): 1580-1592

    Abstract

    ?2-Adrenergic receptors (?2AR) transactivate epidermal growth factor receptors (EGFR) through formation of a ?2AR-EGFR complex that requires activation of Src to mediate signaling. Here, we show that both lipid and protein kinase activities of the bifunctional phosphoinositide 3-kinase (PI3K) enzyme are required for ?2AR-stimulated EGFR transactivation. Mechanistically, the generation of phosphatidylinositol (3,4,5)-tris-phosphate (PIP3) by the lipid kinase function stabilizes ?2AR-EGFR complexes while the protein kinase activity of PI3K regulates Src activation by direct phosphorylation. The protein kinase activity of PI3K phosphorylates serine residue 70 on Src to enhance its activity and induce EGFR transactivation following ?AR stimulation. This newly identified function for PI3K, whereby Src is a substrate for the protein kinase activity of PI3K, is of importance since Src plays a key role in pathological and physiological signaling.

    View details for DOI 10.1016/j.cellsig.2016.05.006

    View details for PubMedID 27169346

    View details for PubMedCentralID PMC4980165

  • AL (Light-Chain) Cardiac Amyloidosis: A Review of Diagnosis and Therapy. Journal of the American College of Cardiology Falk, R. H., Alexander, K. M., Liao, R., Dorbala, S. 2016; 68 (12): 1323-1341

    Abstract

    The amyloidoses are a group of protein-folding disorders in which ?1 organ is infiltrated by proteinaceous deposits known as amyloid. The deposits are derived from 1 of several amyloidogenic precursor proteins, and the prognosis of the disease is determined both by the organ(s) involved and the type of amyloid. Amyloid involvement of the heart (cardiac amyloidosis) carries the worst prognosis of any involved organ, and light-chain (AL) amyloidosis is the most serious form of the disease. The last decade has seen considerable progress in understanding the amyloidoses. In this review, current and novel approaches to the diagnosis and treatment of cardiac amyloidosis are discussed, with particular reference to AL amyloidosis in the heart.

    View details for DOI 10.1016/j.jacc.2016.06.053

    View details for PubMedID 27634125

  • V122I TTR Cardiac Amyloidosis in Patients of African Descent: Recognizing a Missed Disease or the Dog That Didn't Bark? CIRCULATION-HEART FAILURE Alexander, K. M., Falk, R. H. 2016; 9 (9)
  • Grim Messenger: Virchow's Node Presenting with Virchow's Triad AMERICAN JOURNAL OF MEDICINE Alexander, K. M., Vaduganathan, M., Qamar, A., Gerhard-Herman, M. D. 2016; 129 (9): 948-951

    View details for DOI 10.1016/j.amjmed.2016.05.009

    View details for Web of Science ID 000382309900036

    View details for PubMedID 27267288

  • Response by Alexander et al to Letters Regarding Article, "A Shocking Development in a Young Male Athlete With Chest Pain" CIRCULATION Alexander, K. M., Veillet-Chowdhury, M. R., Macintyre, C. J., Loscalzo, J., Bhatt, D. L. 2016; 134 (4): E22-E23
  • Utility of multimodality imaging in myopericarditis with aortitis. Journal of nuclear cardiology Qamar, A., Veeranna, V., Fatima, A., Alexander, K. M., Di Carli, M. F., Bonaca, M. P., Steigner, M., Dorbala, S. 2016: -?

    View details for PubMedID 27174190

  • A Shocking Development in a Young Male Athlete With Chest Pain CIRCULATION Alexander, K. M., Veillet-Chowdhury, M. R., Macintyre, C. J., Loscalzo, J., Bhatt, D. L. 2016; 133 (8): 756-763
  • Mechanical circulatory support for advanced heart failure. Current treatment options in cardiovascular medicine Patel, C. B., Alexander, K. M., Rogers, J. G. 2010; 12 (6): 549-565

    Abstract

    Both acute and chronic systolic heart failure can progress to an advanced phase, resulting in stage D heart failure and even cardiogenic shock. Despite significant progress in the treatment of systolic heart failure using medical and device therapies, this terminal phase continues to be prevalent and associated with unacceptably high morbidity and mortality. Given the inability to offer cardiac transplantation to the majority of those presenting with advanced heart failure, alternative strategies for cardiac replacement therapy are often required. Although there has been interest in using mechanical devices to support the circulation since the advent of cardiopulmonary bypass, it is only in the past 20 years that ventricular assist devices (VAD) have become viable options for therapy. Indeed, we are now entering an era where circulatory assist devices are being used not only to temporarily support patients with post-cardiotomy shock, but also as a long-term treatment in ambulatory heart failure patients. Furthermore, we are now able to utilize data from multicenter trials and registries to guide treatment decisions. These data have clearly shown that VADs improve survival and quality of life in patients with advanced heart failure when implanted as a temporary measure (bridge to recovery and bridge to transplant) or as long-term support (destination therapy). However, with a growing heart failure population there is much work to be done to improve VAD technology, patient selection, post-implantation management, and to define the optimal role for assist devices in the management of systolic heart failure. We are also in the nascent stages of fully understanding the impact of mechanical support on the failing myocardium, and developing research methodologies to study novel therapies in tandem with VADs to facilitate ventricular recovery. These important questions are currently being addressed in ongoing clinical trials, registry analyses, and translational research endeavors.

    View details for DOI 10.1007/s11936-010-0093-6

    View details for PubMedID 21063932

  • A V3 Loop-Dependent gp120 Element Disrupted by CD4 Binding Stabilizes the Human Immunodeficiency Virus Envelope Glycoprotein Trimer JOURNAL OF VIROLOGY Xiang, S., Finzi, A., Pacheco, B., Alexander, K., Yuan, W., Rizzuto, C., Huang, C., Kwong, P. D., Sodroski, J. 2010; 84 (7): 3147-3161

    Abstract

    Human immunodeficiency virus (HIV-1) entry into cells is mediated by a trimeric complex consisting of noncovalently associated gp120 (exterior) and gp41 (transmembrane) envelope glycoproteins. The binding of gp120 to receptors on the target cell alters the gp120-gp41 relationship and activates the membrane-fusing capacity of gp41. Interaction of gp120 with the primary receptor, CD4, results in the exposure of the gp120 third variable (V3) loop, which contributes to binding the CCR5 or CXCR4 chemokine receptors. We show here that insertions in the V3 stem or polar substitutions in a conserved hydrophobic patch near the V3 tip result in decreased gp120-gp41 association (in the unliganded state) and decreased chemokine receptor binding (in the CD4-bound state). Subunit association and syncytium-forming ability of the envelope glycoproteins from primary HIV-1 isolates were disrupted more by V3 changes than those of laboratory-adapted HIV-1 envelope glycoproteins. Changes in the gp120 beta2, beta19, beta20, and beta21 strands, which evidence suggests are proximal to the V3 loop in unliganded gp120, also resulted in decreased gp120-gp41 association. Thus, a gp120 element composed of the V3 loop and adjacent beta strands contributes to quaternary interactions that stabilize the unliganded trimer. CD4 binding dismantles this element, altering the gp120-gp41 relationship and rendering the hydrophobic patch in the V3 tip available for chemokine receptor binding.

    View details for DOI 10.1128/JVI.02587-09

    View details for Web of Science ID 000275307400002

    View details for PubMedID 20089638

    View details for PubMedCentralID PMC2838131

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