Clinical Focus

  • Cardiology

Academic Appointments

Honors & Awards

  • AHA Mentored Clinical & Population Research Award, American Heart Association (2016-2018)
  • ACCF/Merck Cardiovascular Research Fellow, American College of Cardiology Foundation (2013-2014)
  • Soros Fellow, Paul & Daisy Soros Fellowship for New Americans (2003-2005)
  • British Marshall Scholar, Marshall Aid Commemoration Commission (2001-2003)

Professional Education

  • Fellowship:Stanford University Interventional Cardiology Fellowship (2015) CA
  • Fellowship:Stanford University Cardiovascular Medicine Fellowship (2013) CA
  • Residency:UCSF-Internal Medicine (2010) CA
  • Medical Education:Stanford University School of Medicine Registrar (2007) CA
  • Fellowship, Stanford University School of Medicine, Interventional Cardiology (2015)
  • Fellowship, Stanford University School of Medicine, Cardiology (2013)
  • Residency, University of California, San Francisco, Internal Medicine (2010)
  • MD, Stanford School of Medicine (2007)
  • MBA, Oxford University (2003)
  • MSc, London School of Economics, Health Policy, Planning & Financing (2002)
  • BS, University of California, Berkeley, Molecular Environmental Biology (2001)


Graduate and Fellowship Programs


All Publications

  • Racial Differences in Quality of Anticoagulation Therapy for Atrial Fibrillation (from the TREAT-AF Study) AMERICAN JOURNAL OF CARDIOLOGY Yong, C., Azarbal, F., Abnousi, F., Heidenreich, P. A., Schmitt, S., Fan, J., Than, C. T., Ullal, A. J., Yang, F., Phibbs, C. S., Frayne, S. M., Ho, P. M., Shore, S., Mahaffey, K. W., Turakhia, M. P. 2016; 117 (1): 61-68


    The influence of race on quality of anticoagulation control is not well described. We examined the association between race, international normalized ratio (INR) monitoring intensity, and INR control in warfarin-treated patients with atrial fibrillation (AF). Using data from the Veterans Health Administration (VHA), we performed a retrospective cohort study of 184,161 patients with a new diagnosis of AF/flutter from 2004 to 2012 who received any VHA prescription within 90 days of diagnosis. The primary predictor was race, ascertained from multiple VHA and linked Medicare demographic files. The primary outcome was first-year and long-term time in therapeutic range (TTR) of INR 2.0 to 3.0. Secondary outcomes were INR monitoring intensity and warfarin persistence. Of the 116,021 patients who received warfarin in the cohort, INR monitoring intensity was similar across racial groups. However, TTR was lowest in blacks and highest in whites (first year 0.49 ± 0.23 vs 0.57 ± 0.21, p <0.001; long term 0.52 ± 0.20 vs 0.59 ± 0.18, p <0.001); 64% of whites and 49% of blacks had long-term TTR >55% (p <0.001). After adjusting for site and patient-level covariates, black race was associated with lower first-year and long-term TTRs (4.2% and 4.1% below the conditional mean, relative to whites; p <0.0001 for both). One-year warfarin persistence was slightly lower in blacks compared to whites (58% vs 60%, p <0.0001). In conclusion, in patients with AF anticoagulated with warfarin, differences in INR control are most evident among blacks, underscoring the need to determine if other types of intensive management or warfarin alternatives may be necessary to improve anticoagulation among vulnerable AF populations.

    View details for DOI 10.1016/j.amjcard.2015.09.047

    View details for Web of Science ID 000368048900010

    View details for PubMedID 26552504

  • The Evolution of Temporary Percutaneous Mechanical Circulatory Support Devices: a Review of the Options and Evidence in Cardiogenic Shock CURRENT CARDIOLOGY REPORTS Abnousi, F., Yong, C. M., Fearon, W., Banerjee, D. 2015; 17 (6)
  • Socioeconomic Inequalities in Quality of Care and Outcomes Among Patients With Acute Coronary Syndrome in the Modern Era of Drug Eluting Stents JOURNAL OF THE AMERICAN HEART ASSOCIATION Yong, C. M., Abnousi, F., Asch, S. M., Heidenreich, P. A. 2014; 3 (6)
  • Justification of an Introductory Electrocardiogram Teaching Mnemonic by Demonstration of its Prognostic Value AMERICAN JOURNAL OF MEDICINE Soofi, M., Yong, C., Froelicher, V. 2014; 127 (12): 1202-1207


    With diminishing time afforded to electrocardiography in the medical curriculum, we have found Sibbitt's simple mnemonic, the Diagonal Line Lead Rule, for a pattern recognition approach to 12-lead electrocardiogram (ECG) interpretation to be appreciated by students. However, it still lacks universal acceptance because its clinical utility has not been documented. The study objective was to demonstrate the clinical utility of the Diagonal Line Lead ECG Teaching Rule.After excluding ECGs of high-risk patients with Wolff-Parkinson-White syndrome and QRS durations greater than 120 ms, the initial ECGs of the remaining 43,798 patients were scored according to the Diagonal Line Lead Rule. A total of 45,497 patients from the Veterans Affairs Palo Alto Healthcare System were referred for a routine initial resting ECG from 1987 to 1999. We determined cardiovascular mortality with 8 years of follow-up.In patients with normal QRS duration, diagnostic Q-wave or T-wave inversions isolated to the diagonal line leads showed no increased risk of cardiovascular death. Q-wave or T-wave inversion in any other lead was significantly associated with cardiovascular death with an age-adjusted Cox hazard of 2.6 (confidence interval, 2.4-2.8; P < .0001) and an annual cardiovascular mortality rate of 3.0%. Leads V4-V6, I, and aVL were especially significant predictors of cardiovascular death, with a Cox hazard greater than 3.Our analysis demonstrates the prognostic power and clinical utility of a simple mnemonic for 12-lead ECG interpretation that can facilitate ECG teaching and interpretation.

    View details for DOI 10.1016/j.amjmed.2014.07.016

    View details for Web of Science ID 000346029400038

    View details for PubMedID 25065339

  • Transcatheter CoreValve valve-in-valve implantation in a stentless porcine aortic valve for severe aortic regurgitation. Clinical case reports Yong, C. M., Buchbinder, M., Giacomini, J. C. 2014; 2 (6): 281-285


    We describe the first valve-in-valve Corevalve transcatheter aortic valve replacement in the St. Jude Toronto stentless porcine aortic valve in the United States, which enabled this 59-year-old patient with a history of bacterial endocarditis and aortic regurgitation to avoid heart transplant with complete resolution of his severe left ventricular dysfunction.

    View details for DOI 10.1002/ccr3.113

    View details for PubMedID 25548631

  • Patterns and prognosis of all components of the J-wave pattern in multiethnic athletes and ambulatory patients AMERICAN HEART JOURNAL Muramoto, D., Yong, C. M., Singh, N., Aggarwal, S., Perez, M., Ashley, E., Hadley, D., Froelicher, V. 2014; 167 (2): 259-266


    Despite recent concern about the significance of the J-wave pattern (also often referred to as early repolarization) and the importance of screening in athletes, there are limited rigorous prognostic data characterizing the 3 components of the J-wave pattern (ST elevation, J waves, and QRS slurs). We aim to assess the prevalence, patterns, and prognosis of the J-wave pattern among both stable clinical and athlete populations.We retrospectively studied 4,041 electrocardiograms from a multiethnic clinical population from 1997 to 1999 at the Veterans Affairs Palo Alto Health Care System. We also examined preparticipation electrocardiograms of 1,114 Stanford University varsity athletes from 2007 to 2008. Strictly defined criteria for components of the J-wave pattern were examined. In clinical subjects, prognosis was assessed using the end point of cardiovascular death after 7 years of follow-up.Components of the J-wave pattern were most prevalent in males; African Americans; and, particularly, athletes, with the greatest variations demonstrated in the lateral leads. ST elevation was the most common. Inferior J waves and slurs, previously linked to cardiovascular risk, were observed in 9.6% of clinical subjects and 12.3% of athletes. J waves, slurs, or ST elevation was not associated with time to cardiovascular death in clinical subjects, and ST-segment slope abnormalities were not prevalent enough in conjunction with them to reach significance.J waves, slurs, or ST elevation was not associated with increased hazard of cardiovascular death in our large multiethnic, ambulatory population. Even subsets of J-wave patterns, recently proposed to pose a risk of arrhythmic death, occurred at such a high prevalence as to negate their utility in screening.

    View details for DOI 10.1016/j.ahj.2013.10.027

    View details for Web of Science ID 000329761200019

  • Prognostic implications of the J wave ECG patterns JOURNAL OF ELECTROCARDIOLOGY Yong, C. M., Perez, M., Froelicher, V. 2013; 46 (5): 408-410
  • Variability in quantitative and qualitative analysis of intravascular ultrasound and frequency domain optical coherence tomography CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Abnousi, F., Waseda, K., Kume, T., Otake, H., Kawarada, O., Yong, C. M., Fitzgerald, P. J., Honda, Y., Yeung, A. C., Fearon, W. F. 2013; 82 (3): E192-E199

    View details for DOI 10.1002/ccd.24871

    View details for Web of Science ID 000323454100008

  • J wave patterns and ST elevation in women JOURNAL OF ELECTROCARDIOLOGY Yong, C. M., Zarafshar, S., Froelicher, V. 2013; 46 (5): 417-423

    View details for Web of Science ID 000330268800010

    View details for PubMedID 23981308

  • The Electrocardiogram at a Crossroads CIRCULATION Yong, C. M., Froelicher, V., Wagner, G. 2013; 128 (1): 79-82
  • A novel stress echocardiography pattern for myocardial bridge with invasive structural and hemodynamic correlation. Journal of the American Heart Association Lin, S., Tremmel, J. A., Yamada, R., Rogers, I. S., Yong, C. M., Turcott, R., McConnell, M. V., Dash, R., Schnittger, I. 2013; 2 (2)


    Patients with a myocardial bridge (MB) and no significant obstructive coronary artery disease (CAD) may experience angina presumably from ischemia, but noninvasive assessment has been limited and the underlying mechanism poorly understood. This study seeks to correlate a novel exercise echocardiography (EE) finding for MBs with invasive structural and hemodynamic measurements.Eighteen patients with angina and an EE pattern of focal end-systolic to early-diastolic buckling in the septum with apical sparing were prospectively enrolled for invasive assessment. This included coronary angiography, left anterior descending artery (LAD) intravascular ultrasound (IVUS), and intracoronary pressure and Doppler measurements at rest and during dobutamine stress. All patients were found to have an LAD MB on IVUS. The ratios of diastolic intracoronary pressure divided by aortic pressure at rest (Pd/Pa) and during dobutamine stress (diastolic fractional flow reserve [dFFR]) and peak Doppler flow velocity recordings at rest and with stress were successfully performed in 14 patients. All had abnormal dFFR (≤0.75) at stress within the bridge, distally or in both positions, and on average showed a more than doubling in peak Doppler flow velocity inside the MB at stress. Seventy-five percent of patients had normalization of dFFR distal to the MB, with partial pressure recovery and a decrease in peak Doppler flow velocity.A distinctive septal wall motion abnormality with apical sparing on EE is associated with a documented MB by IVUS and a decreased dFFR. We posit that the septal wall motion abnormality on EE is due to dynamic ischemia local to the compressed segment of the LAD from the increase in velocity and decrease in perfusion pressure, consistent with the Venturi effect.

    View details for DOI 10.1161/JAHA.113.000097

    View details for PubMedID 23591827

  • A Novel Stress Echocardiography Pattern for Myocardial Bridge With Invasive Structural and Hemodynamic Correlation JOURNAL OF THE AMERICAN HEART ASSOCIATION Lin, S., Tremmel, J. A., Yamada, R., Rogers, I. S., Yong, C. M., Turcott, R., McConnell, M. V., Dash, R., Schnittger, I. 2013; 2 (2)
  • International differences in patient and physician perceptions of "high quality" healthcare: A model from pediatric cardiology AMERICAN JOURNAL OF CARDIOLOGY Garson, A., Yong, C. M., Yock, C. A., McClellan, M. B. 2006; 97 (7): 1073-1075


    Although the quality of health care would logically seem to be a universal concept, this study hypothesized that physicians and their patients could differ in their perceptions of "high-quality care" and that those beliefs might vary by country. Such a mismatch in beliefs may be especially important as clinical practice guidelines developed in the United States are globalized. A survey of 20 statements describing various components of health care delivery and quality was sent to pediatric cardiologists in 33 countries, who ranked the statements in order of priority for ideal health care. Each participating physician administered the questionnaire to the parents of children with congenital heart disease; 554 questionnaires were received and analyzed. A subanalysis of 9 countries with the largest number of responses was done (Canada, the Czech Republic, France, Germany, Italy, The Netherlands, Sweden, the United Kingdom, and the United States). Doctors and parents rated the same 4 statements among the top 5: "the doctor is skillful and knowledgeable"; "the doctor explains health problems, tests, and treatments in a way the patient can understand"; "a basic level of healthcare is available to all citizens regardless of their ability to pay"; and "treatment causes the patient to feel physically well." Overall, parents' responses differed more among countries than those of physicians; the magnitude of the difference between parents and physicians varied by country. This discrepancy highlights a potential mismatch between patients' and physicians' views about the desired components of health care delivery, in particular the application of American quality standards for health care to systems in other countries.

    View details for DOI 10.1016/j.amjcard.2005.10.051

    View details for Web of Science ID 000236708700029

    View details for PubMedID 16563919