Professional Education


  • MD, David Geffen School of Medicine at UCLA (2024)
  • BS with Honors, UCLA, Neuroscience (2019)

All Publications


  • Comparison of Cardiac Allograft Vasculopathy Incidence Between Simultaneous Multi-Organ and Isolated Heart Transplant Recipients in the United States. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Shahandeh, N., Kim, J. S., Klomhaus, A. M., Tehrani, D., Hsu, J. J., Nsair, A., Khush, K. K., Fearon, W. F., Parikh, R. V. 2024

    Abstract

    Prior studies have shown reduced development of cardiac allograft vasculopathy (CAV) in multi-organ transplant recipients. The aim of this study was to compare the incidence of CAV between isolated heart transplants and simultaneous multi-organ heart transplants in the contemporary era.We utilized the Scientific Registry of Transplant Recipients to perform a retrospective analysis of first-time adult heart transplant recipients between January 1, 2010 and December 31, 2019 in the United States. The primary endpoint was the development of angiographic CAV within 5 years of follow-up.Among 20,591 patients included in the analysis, 1,279 (6%) underwent multi-organ heart transplantation (70% heart-kidney, 16% heart-liver, 13% heart-lung, and 1% triple-organ) and 19,312 (94%) were isolated heart transplant recipients. The average age was 53 years and 74% were male. There were no significant between-group differences in cold ischemic time between the groups. The incidence of acute rejection during the first year after transplant was significantly lower in the multi-organ group (18% vs. 33%, p<0.01). The 5-year incidence of CAV was 33% in the isolated heart group and 27% in the multi-organ group (p<0.0001); differences in CAV incidence were seen as early as 1 year after transplant and persisted over time. In multivariable analysis, multi-organ heart transplant recipients had a significantly lower likelihood of CAV at 5 years (hazard ratio=0.76, 95% confidence interval: 0.66-0.88, p<0.01).Simultaneous multi-organ heart transplantation is associated with significantly lower long-term risk of angiographic CAV compared with isolated heart transplantation in the contemporary era.

    View details for DOI 10.1016/j.healun.2024.06.014

    View details for PubMedID 38950666

  • Surgical education for medical students: Virtual game-based learning. Medical education Kim, J. S., Leung, K. L., Eng, I. K., Sridhar, A. 2024; 58 (5): 588-589

    View details for DOI 10.1111/medu.15332

    View details for PubMedID 38362925

  • A Rare Case of Mature Cystic Teratoma with Infantile Hemangioma and Pericardial Invasion Kim, J. S., Eng, I. K., Yee, J. M., Lee, M., Deshmukh, M., Thomas, M. Journal of Medical Imaging & Case Reports. 2024 ; 8 (1): 14-17

    Abstract

    Distinguishing the origin of mediastinal masses as pericardial or pericardial is difficult and has significant implications for subsequent treatment. We present the first reported case of a mature cystic teratoma with infantile hemangioma that initially appeared to be a paracardial mass abutting the pericardium but was found to be a paracardial mass with pericardial invasion. Although computed tomography (CT) and magnetic resonance imaging (MRI) are the diagnostic modalities of choice to localize and assess infiltrative growth into surrounding structures, imaging may not fully capture the underlying pathology as in our case.

  • Outcomes of heart transplant recipients bridged with percutaneous versus durable left ventricular assist devices. Clinical transplantation Xia, Y., Kim, J. S., Eng, I. K., Nsair, A., Ardehali, A., Shemin, R. J., Kwon, M. H. 2023; 37 (4): e14904

    Abstract

    The new United Network for Organ Sharing (UNOS) heart allocation policy prioritizes temporary percutaneous over durable left ventricular assist devices (LVAD) as bridge to transplant. We sought to examine 1-year outcomes of heart transplant recipients bridged with Impella versus durable LVADs.All primary adult orthotopic heart transplant recipients registered in UNOS between January 2016 and June 2021 were analyzed. Recipients were identified as being bridged with isolated durable or percutaneous LVAD at the time of transplant. Baseline characteristics were compared and 1-year survival was examined using the Kaplan Meier method and multivariable Cox proportional hazards regression.During our study period, heart transplant recipients bridged with LVADs were divided between 5422(94%) durable and 324(6%) percutaneous options. Impella-bridged recipients were more likely to be status 1A under the old allocation system (98% vs. 70%, p < .01) and status 2 or higher under the new allocation system (99% vs. 24%, p < .01). Impella-bridged recipients were less likely to be obese (27% vs. 42%, p < .01), have ischemic cardiomyopathy (27% vs. 34%, p < .01), and were more likely to be on inotropic agents at the time of transplant (68% vs. 6%, p < .01). One-year post-transplant survival was not significantly different between the two groups on univariable (HR .87, 95% CI .56-1.37) or multivariable analysis (aHR .63, 95% CI .37-1.07).Following the UNOS allocation policy change, Impella utilization has increased with no significant difference in 1-year survival compared to bridge with durable LVADs. Impella may be a reasonable alternative to durable LVADs in select patients.

    View details for DOI 10.1111/ctr.14904

    View details for PubMedID 36594638

  • Transcatheter Aortic Valve Replacement for Severe Aortic Valve Stenosis: Do Patients Experience Better Quality of Life Regardless of Gradient? Texas Heart Institute journal Simone, A., Kim, J. S., Huchting, J., Rafique, A., Ozcaglayan, R., Shemin, R. J., Aksoy, O., Kwon, M. H. 2023; 50 (1)

    Abstract

    Aortic valve replacement improves survival for patients with low-gradient aortic valve stenosis, but there is a paucity of data on postoperative quality of life for this population.In a single-center retrospective analysis of 304 patients with severe aortic valve stenosis who underwent transcatheter aortic valve replacement, patients were divided into 4 groups based on mean pressure gradient, left ventricular ejection fraction, and stroke volume index. Using the Kansas City Cardiomyopathy Questionnaire-12, quality of life was assessed immediately before and 1 month after transcatheter aortic valve replacement.Most patients in the low-flow, low-gradient group were men; this group had higher relative rates of cardiovascular disease and type 2 diabetes than the paradoxical low-flow, low-gradient group; the normal-flow, low-gradient group; and the high-gradient group. All-cause mortality did not differ significantly among the groups at 1 month after surgery, and all groups experienced a significant improvement in quality-of-life scores after surgery. The mean improvement was 27 points in the low-flow, low-gradient group, 25 points in the paradoxical low-flow, low-gradient group, 30 points in the normal-flow, low-gradient group, and 30 points in the high-gradient group (all P < .001).Quality of life improves significantly across all subgroups of aortic valve stenosis after trans-catheter aortic valve replacement, regardless of flow characteristics or aortic valve gradients.

    View details for DOI 10.14503/THIJ-21-7659

    View details for PubMedID 36695735

    View details for PubMedCentralID PMC9969767

  • Retained left ventricular assist device driveline in a heart transplant recipient: A case report. JTCVS techniques Kim, J. S., Lee, B., Chu, A., Kwon, M. H. 2022; 15: 133-135

    View details for DOI 10.1016/j.xjtc.2022.07.001

    View details for PubMedID 36276676

    View details for PubMedCentralID PMC9579709

  • Early Trends in Cardiac Allograft Vasculopathy After Implementation of the 2018 Donor Heart Allocation Policy in the United States: Short Title: CAV Trend After Allocation Policy Change. American heart journal Tehrani, D. M., Kim, J. S., Hsu, J. J., Nsair, A., Khush, K. K., Fearon, W. F., Parikh, R. V. 2022

    Abstract

    STUDY OBJECTIVE: To evaluate the impact of the new donor heart allocation system implemented in the United States in October 2018 on development of early cardiac allograft vasculopathy (CAV).DESIGN: Retrospective cohort study.PARTICIPANTS: Adult (≥ 18 years) heart transplant recipients registered in the United Network for Organ Sharing database between October 18, 2015 - October 17, 2018 (old system) and October 18, 2018 - May 31, 2020 (new system).MAIN OUTCOME MEASURE: Incidence of angiographic CAV at 1 year (accelerated CAV) in the overall transplant population and among the highest acuity subgroup-Status 1A (old) and Status 1 or 2 (new). We included recipient and donor demographic, cardiovascular, and transplant factors in multivariable logistic regression models to identify predictors of accelerated CAV.RESULTS: Of 10,375 transplant recipients, 6,660 (64%) and 3,715 (36%) were listed in the old and new allocation cohorts, respectively. The incidence of accelerated CAV was 521 (8%) in the old period compared with 272 (7%) in the new period (p = 0.36). Similar incidence rates were observed in the highest acuity subgroup-363 (8%) compared with 143 (7%), respectively (p = 0.13). In adjusted analyses of the high-acuity cohort, the new allocation system was not associated with a higher likelihood of accelerated CAV (odds ratio = 0.87, 95% confidence interval: 0.70-1.08, p = 0.20).CONCLUSIONS: The new donor heart allocation system is not associated with development of accelerated angiographic CAV at 1 year, including among recipients requiring the most urgent transplants.

    View details for DOI 10.1016/j.ahj.2022.08.002

    View details for PubMedID 35970399

  • Nontechnical skills training in cardiothoracic surgery: A pilot study. The Journal of thoracic and cardiovascular surgery Kim, J. S., Hernandez, R. A., Smink, D. S., Yule, S., Jackson, N. J., Shemin, R. J., Kwon, M. H. 2022; 163 (6): 2155-2162.e4

    Abstract

    The importance of nontechnical skills in surgery is widely recognized. We demonstrate the feasibility of administering and assessing the results of a formal Non-Technical Skills in Surgery (NOTSS) curriculum to cardiothoracic surgery residents.Eight cardiothoracic surgery residents participated in the NOTSS curriculum. They were assessed on their cognitive (situation awareness, decision-making) and social (communication and teamwork, leadership) skills based on simulated vignettes. The residents underwent pretraining NOTSS assessments followed by self-administered confidence ratings regarding the 4 skills. Subsequently, a formal NOTSS lecture was delivered and additional readings from the NOTSS textbook was assigned. A month later, the residents returned for post-training NOTSS assessments and self-administered confidence ratings. Changes across days (or within-day before vs after curriculum) were assessed using Wilcoxon signed rank test.There was a significant improvement in the overall NOTSS assessment score (P = .01) as well as in the individual categories (situation awareness, P = .02; decision-making, P = .02; communication and teamwork, P = .01; leadership, P = .02). There was also an increase in resident self-perception of improvement on the post-training day (P = .01).We have developed a simulation-based NOTSS curriculum in cardiothoracic surgery that can be formally integrated into the current residency education. This pilot study indicates the feasibility of reproducible assessments by course educators and self-assessments by participating residents in nontechnical skills competencies.

    View details for DOI 10.1016/j.jtcvs.2021.01.108

    View details for PubMedID 33676757

  • Fractional Flow Reserve in End-Stage Liver Disease. The American journal of cardiology Kumar, P., Kim, J. S., Gordin, J., Honda, H. M., Suh, W., Lee, M. S., Press, M., Nsair, A., Aksoy, O., Busuttil, R. W., Tobis, J., Parikh, R. V. 2022; 166: 122-126

    Abstract

    Fractional flow reserve (FFR) determines the functional significance of epicardial stenoses assuming negligible venous pressure (Pv) and microvascular resistance. However, these assumptions may be invalid in end-stage liver disease (ESLD) because of fluctuating Pv and vasodilation. Accordingly, all patients with ESLD who underwent right-sided cardiac catheterization and coronary angiography with FFR as part of their orthotopic liver transplantation evaluation between 2013 and 2018 were included in the present study. Resting mean distal coronary pressure (Pd)/mean aortic pressure (Pa), FFR, and Pv were measured. FFR accounting for Pv (FFR - Pv) was defined as (Pd - Pv)/(Pa - Pv). The hyperemic effect of adenosine was defined as resting Pd/Pa - FFR. The primary outcome was all-cause mortality at 1 year. In 42 patients with ESLD, 49 stenoses were interrogated by FFR (90% were <70% diameter stenosis). Overall, the median model for ESLD score was 16.5 (10.8 to 25.5), FFR was 0.87 (0.81 to 0.94), Pv was 8 mm Hg (4 to 14), FFR-Pv was 0.86 (0.80 to 0.94), and hyperemic effect of adenosine was 0.06 (0.02 to 0.08). FFR-Pv led to the reclassification of 1 stenosis as functionally significant. There was no significant correlation between the median model for ESLD score and the hyperemic effect of adenosine (R = 0.10). At 1 year, 13 patients had died (92% noncardiac in etiology), and patients with FFR ≤0.80 had significantly higher all-cause mortality (73% vs 17%, p = 0.001. In conclusion, in patients with ESLD who underwent orthotopic liver transplantation evaluation, Pv has minimal impact on FFR, and the hyperemic effect of adenosine is preserved. Furthermore, even in patients with the predominantly angiographically-intermediate disease, FFR ≤0.80 was an independent predictor of all-cause mortality.

    View details for DOI 10.1016/j.amjcard.2021.11.031

    View details for PubMedID 34949471

  • Validity of echocardiography for detection of left ventricular thrombus with surgical validation in patients awaiting durable left ventricular assist device. Journal of cardiac surgery Bae, D. J., Wadia, S. K., Kim, J. S., Moreno, E., Ardehali, R., Shemin, R. J., Kwon, M. H. 2021; 36 (8): 2722-2728

    Abstract

    Unrecognized left ventricular thrombi (LVT) can have devastating clinical implications and precludes patients with end-stage heart failure from undergoing left ventricular assist device (LVAD) implantation without cardiopulmonary bypass assistance. We assessed the reliability of an echocardiogram to diagnose LVT in patients with end-stage heart disease who underwent LVAD implantation.A single-center retrospective study evaluated 232 consecutive adult patients requiring implantation of durable LVADs between 2005 and 2019. The validity of preoperative transthoracic echocardiogram (TTE) and intraoperative transesophageal echocardiogram (TEE) for diagnosing LVT was compared to direct inspection at the time of LVAD implantation.There were 232 patients that underwent LVAD implantation, with 226 patients (97%) receiving a preoperative TTE. Of those 226 patients, 32 patients (14%) received ultrasound enhancing agents (UEA). Intraoperative TEE images were available in 195 patients (84%). The sensitivity of TTE without UEA was 22% and specificity was 90% for detecting LVT, compared to 50% and 86%, respectively, for TTE with UEA. For intraoperative TEE, the sensitivity and specificity were 46% and 96%, respectively. The false omission rate ranged from 4% to 8% for all modalities of echocardiography.Among patients undergoing LVAD implantation, preoperative TTE and intraoperative TEE had poor sensitivity for LVT detection. Up to 8% of echocardiograms were incorrectly concluded to be negative for LVT on surgical validation. The low sensitivity and positive predictive value for diagnosing LVT suggest that echocardiography has limited reliability in this cohort of patients who are at high risk of LVT formation and its subsequent complications.

    View details for DOI 10.1111/jocs.15662

    View details for PubMedID 34047391