Clinical Focus


  • Pediatric Cardiology

Academic Appointments


Professional Education


  • Fellowship: Stanford University Pediatric Cardiology Fellowship (2022) CA
  • Fellowship: Stanford University Pediatric Cardiology Fellowship (2021) CA
  • Board Certification: American Board of Pediatrics, Pediatrics (2017)
  • Residency: Phoenix Children's Hospital Pediatric Residency (2017) AZ
  • Medical Education: University of Arizona College of Medicine Office of the Registrar (2014) AZ

All Publications


  • Criteria for Early Pacemaker Implantation in Patients With Postoperative Heart Block After Congenital Heart Surgery. Circulation. Arrhythmia and electrophysiology Duong, S. Q., Shi, Y., Giacone, H., Navarre, B., Gal, D., Han, B., Sganga, D., Ma, M., Reddy, C. D., Shin, A., Kwiatkowski, D. M., Dubin, A. M., Scheinker, D., Algaze, C. A. 2022: e011145

    Abstract

    Guidelines recommend observation for atrioventricular node recovery until postoperative days (POD) 7 to 10 before permanent pacemaker placement (PPM) in patients with heart block after congenital cardiac surgery. To aid in surgical decision-making for early PPM, we established criteria to identify patients at high risk of requiring PPM.We reviewed all cases of second degree and complete heart block (CHB) on POD 0 from August 2009 through December 2018. A decision tree model was trained to predict the need for PPM amongst patients with persistent CHB and prospectively validated from January 2019 through March 2021. Separate models were developed for all patients on POD 0 and those without recovery by POD 4.Of the 139 patients with postoperative heart block, 68 required PPM. PPM was associated with older age (3.2 versus 1.0 years; P=0.018) and persistent CHB on POD 0 (versus intermittent CHB or second degree heart block; 87% versus 58%; P=0.001). Median days [IQR] to atrioventricular node recovery was 2 [0-5] and PPM was 9 [6-11]. Of the 100 cases of persistent CHB (21 in the validation cohort), 59 (59%) required PPM. A decision tree model identified 4 risk factors for PPM in patients with persistent CHB: (1) aortic valve replacement, subaortic stenosis repair, or Konno procedure; (2) ventricular L-looping; (3) atrioventricular valve replacement; (4) and absence of preoperative antiarrhythmic agent (in POD 0 model only). The POD 4 model specificity was 0.89 [0.67-0.99] and positive predictive value was 0.94 [95% CI 0.81-0.98], which was stable in prospective validation (positive predictive value 1.0).A data-driven analysis led to actionable criteria to identify patients requiring PPM. Patients with left ventricular outflow tract surgery, atrioventricular valve replacement, or ventricular L-Looping could be considered for PPM on POD 4 to reduce risks of temporary pacing and improve care efficiency.

    View details for DOI 10.1161/CIRCEP.122.011145

    View details for PubMedID 36306332

  • Ventricular arrhythmias following transcatheter pulmonary valve replacement with the harmony TPV25 device. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions Taylor, A., Yang, J., Dubin, A., Chubb, M. H., Motonaga, K., Goodyer, W., Giacone, H., Peng, L., Romfh, A., McElhinney, D., Ceresnak, S. 2022

    Abstract

    BACKGROUND: Transcatheter pulmonary valve replacement (TPVR) with the Harmony valve (Medtronic, Inc.) was recently approved to treat postoperative native outflow tract pulmonary regurgitation. While the 22mm Harmony valve Early Feasibility Study demonstrated ventricular tachycardia (VT) in only 5% of patients, little is known about ventricular arrhythmias after TPVR with the larger 25mm valve (TPV25).METHODS: A single center review was performed of patients with TPV25 implant from 2020 to 2021. Demographic, cardiac, procedural, and postimplant cardiac telemetry data were collected and compared between patients who did and did not have peri-implant ventricular arrhythmia.RESULTS: Thirty patients underwent TPV25 at a median age of 30 years. On postimplant telemetry, VT events were documented in 12 patients (40%); 11 nonsustained VT (NSVT) (median 3 episodes per patient and 6 beats per episode, maximum 157 episodes) and 1 sustained VT (3%), with Torsades de Pointes secondary to a short coupled premature ventricular contraction (PVC). VT events were associated with annular valve positioning (p<0.001) and increased postimplant PVC burden (p<0.0001), but there was no association between VT and other demongraphic, historical, or procedural factors. The frequency of NSVT events fell from 3/hfrom 0 to 12h postimplant to 0.5/hr from 12 to 24h (p<0.001).CONCLUSION: VT occurred commonly (40%) in the first 24h after TPV25 implant, with self-limited NSVT in 11 of 12 patients and 1 patient with cardiac arrest secondary to Torsades de Pointes. VT only occurred with annular valve positioning. Larger, longer-term studies are needed to determine risk factors for and natural history of post-TPVR VT.

    View details for DOI 10.1002/ccd.30393

    View details for PubMedID 36198126

  • Risk Factors and Outcomes of Sudden Cardiac Arrest in Pediatric Heart Transplant Recipients. American heart journal Hollander, S. A., Barkoff, L., Giacone, H., Adamson, G. T., Kaufman, B. D., Motonaga, K. S., Dubin, A. M., Chubb, H. 2022

    Abstract

    Sudden cardiac arrest (SCA) is a prevailing cause of mortality after pediatric heart transplant (HT) but remains understudied. We analyzed the incidence, outcomes, and risk factors for SCA at our center.Retrospective review of all pediatric HT patients at our center from 1/1/2009-9/1/2021. SCA was defined as an abrupt loss of cardiac function requiring cardiopulmonary resuscitation and/or mechanical circulatory support (MCS). Events that occurred in the setting of limited resuscitative wishes, or while on MCS were excluded. Patient characteristics and risk factors were analyzed.Fourteen of 254 (6%) experienced SCA at a median of 3 (1, 4) years post-HT. Seven (50%) events occurred out-of-hospital. Eleven (79%) died from their initial event, 2 (18%) after failure to separate from extracorporeal membrane (ECMO). In univariate analysis, black race, younger donor age, prior acute cellular rejection (ACR) episode, pacemaker and/or ICD in place, and pre-mortem diagnosis of allograft vasculopathy were associated with SCA (P=0.003-0.02). In multivariable analysis, history of ACR, younger donor age, and black race retained significance. [OR=6.3, 95% CI: 1.6-25.4, P=0.01], [OR=0.9, 95% CI: 0.8-1, P=0.04], and [OR=7.3, 95% CI: 1.1-49.9, P=0.04], respectively. SCA occurred in 3 patients with a functioning ICD or pacemaker, which failed to restore a perfusing rhythm.SCA occurs relatively early after pediatric HT and is usually fatal. Half of events happen at home. Those who received younger donors, have a history of ACR, or are of black race are at increased risk. ICDs/pacemakers may offer limited protection.

    View details for DOI 10.1016/j.ahj.2022.06.003

    View details for PubMedID 35705134