Clinical Focus


  • Cardiac Surgery

Academic Appointments


Professional Education


  • Fellowship: University of Toronto Hospital for Sick Children (2018) Canada
  • Board Certification: Royal College of Physicians and Surgeons, Cardiac Surgery (2017)
  • Residency: Laval University Cardiac Surgery Residency (2017)
  • MPH, Harvard University (2015)
  • Medical Education: McGill University Faculty of Medicine (2011) Canada

All Publications


  • Surgical repair of peripheral pulmonary artery stenosis: A 2-decade experience with 145 patients. The Journal of thoracic and cardiovascular surgery Felmly, L. M., Mainwaring, R. D., Collins, R. T., Lechich, K., Martin, E., Ma, M., Hanley, F. L. 2022

    Abstract

    BACKGROUND: Peripheral pulmonary artery stenosis (PPAS) is a relatively rare form of congenital heart disease often associated with Williams syndrome, Alagille syndrome, and elastin arteriopathy. This disease is characterized by stenoses at nearly all lobar and segmental ostia and results in systemic-level right ventricular pressures. The current study summarizes our experience with the surgical treatment of PPAS.METHODS: This was a retrospective review of 145 patients who underwent surgical repair of PPAS. This included 43 patients with Williams syndrome, 39 with Alagille syndrome, and 21 with elastin arteriopathy. Other diagnoses include tetralogy of Fallot with PPAS (n=21), truncus arteriosus (n=5), transposition (n=3), double-outlet right ventricle (n=2), arterial tortuosity syndrome (n=3), and other (n=8).RESULTS: The median preoperative right ventricle to aortic peak systolic pressure ratio was 1.01 (range, 0.50-1.60) which was reduced to 0.30 (range, 0.17-0.60) postoperatively. The median number of ostial repairs was 17 (range, 6-34) and median duration of cardiopulmonary bypass was 398minutes (range, 92-844). There were 3 in-hospital deaths (2.1%). The median duration of follow-up was 26months (range, 1-220) with 4 late deaths (2.9%). Eighty-two patients have subsequently undergone catheterization and 74 had a pressure ratio <0.50.CONCLUSIONS: The surgical treatment of PPAS resulted in a 70% reduction in right ventricular pressures. At 3years, freedom from death was 94% and 90% of those evaluated maintained low pressures. These results suggest that the surgical treatment of PPAS is highly effective in most patients.

    View details for DOI 10.1016/j.jtcvs.2022.07.037

    View details for PubMedID 36088147

  • The number of postoperative surgical or diagnostic procedures following congenital heart surgery correlates with both mortality and hospital length of stay. Journal of cardiac surgery Capecci, L., Mainwaring, R. D., Collins, R. T., Sidell, D., Martin, E., Lamberti, J. J., Hanley, F. L. 2022

    Abstract

    BACKGROUND: Outcomes for congenital heart disease have dramatically improved over the past several decades. However, there are patients who encounter intraoperative or postoperative complications and ultimately do not survive. It was our hypothesis that the number of postoperative procedures (including surgical and unplanned diagnostic procedures) would correlate with hospital length of stay and operative mortality.METHODS: This was a retrospective review of 938 consecutive patients undergoing congenital heart surgery at a single institution over a 2-year timeframe. The number of postoperative surgical and unplanned diagnostic procedures were counted and the impact on hospital length of stay and mortality was assessed.RESULTS: 581 of the 938 (62%) patients had zero postoperative diagnostic or surgical procedures. These patients had a median length of stay of 6 days with a single operative mortality (0.2%). 357 of the 938 (38%) patients had one or more postoperative diagnostic or surgical procedures. These patients had a total of 1586 postoperative procedures. There was a significant correlation between the number of postoperative procedures and both hospital length of stay and mortality (p<.001).Patients who required 10 or more postoperative procedures had a median hospital length of stay of 89 days and had a 50% mortality. There were no survivors in patients who had 15 or more postoperative procedures.CONCLUSIONS: The data demonstrate that the number of postoperative procedures was highly correlated with both hospital length of stay and mortality.

    View details for DOI 10.1111/jocs.16817

    View details for PubMedID 35917407

  • Surgical Repair of Supravalvar Aortic Stenosis in Association With Transverse and Proximal Descending Aortic Abnormalities. World journal for pediatric & congenital heart surgery Mainwaring, R. D., Collins, R. T., Ma, M., Martin, E., Arunamata, A., Algaze-Yojay, C., Hanley, F. L. 2022; 13 (3): 353-360

    Abstract

    BACKGROUND: Supravalvar aortic stenosis (SVAS) may be an isolated defect of the proximal ascending aorta. However, more severe cases have extension of the arteriopathy into the transverse and proximal descending aorta. The purpose of this study was to review our experience with SVAS with and without aortic arch arteriopathy.METHODS: This was a retrospective review of 58 patients who underwent surgical repair of SVAS. The median age at repair was 18 months. A total of 37 patients had Williams syndrome. A total of 31 (53%) patients had associated peripheral pulmonary artery stenosis and 23 (39%) had coronary artery ostial stenosis (CAOS).RESULTS: A total of 37 of 58 (64%) patients had surgical repair of SVAS without the need for arch intervention while 21 (36%) patients had repair of the distal aortic arch. There were 3 (5.2%) operative deaths, 2 of whom had aortic arch involvement and one without arch involvement. There were 2 deaths after discharge from the hospital. Patients who needed arch surgery were more likely to have severe arch gradients compared to those without arch involvement (71% vs 30%, P < .05), were more likely to undergo concomitant procedures for peripheral pulmonary artery stenosis or CAOS (90% vs 62%, P < .05), and to have Williams syndrome (86% vs 51%, P < .05).CONCLUSIONS: More than one-third of patients who had SVAS repair at our institution had procedures directed at the transverse or proximal descending aorta. Patients with arch involvement had more severe arch obstruction, required more concomitant procedures, and were more likely to have Williams syndrome.

    View details for DOI 10.1177/21501351221085975

    View details for PubMedID 35446223

  • Discussion JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Martin, E., Al-Khaldi, A. 2022; 163 (4): 1456-1457

    View details for Web of Science ID 000778453500001

    View details for PubMedID 34649719

  • Airway Characteristics of Patients With 22q11 Deletion Undergoing Pulmonary Artery Reconstruction Surgery: Retrospective Cohort Study. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies Sganga, D., Meister, K., Sidell, D. R., Wise-Faberowski, L., Shek, J., Ma, M., Martin, E., Hanley, F. L., McElhinney, D., Asija, R. 2022

    Abstract

    OBJECTIVES: We have previously shown that patients with a chromosome 22q11 microdeletion are at risk for prolonged respiratory failure after pulmonary artery reconstruction surgery compared with those with normal genotype. We sought to describe preexisting airway abnormalities in this patient population and examine relationships between airway abnormalities and outcomes.DESIGN: Single-center retrospective chart review from Society of Thoracic Surgery and Pediatric Cardiac Critical Care Consortium databases and the electronic medical record.SETTING: Lucile Packard Children's Hospital at Stanford from September 2017 to February 2019.PATIENTS: All patients undergoing pulmonary artery reconstruction surgery were considered for inclusion.INTERVENTIONS: We identified 127 patients meeting study inclusion criteria. Thirty-nine patients met specific criteria and underwent screening preoperative bronchoscopy including microdirect laryngoscopy and lower airway examination. Postoperative bronchoscopy was performed at the discretion of the intensive care team.MEASUREMENTS AND MAIN RESULTS: Airway abnormalities were detected in 25/26 of children (96%) with a chromosome 22q11 deletion who underwent preoperative bronchoscopy. Upper and lower airway pathologies were found in 19/25 (73%) and 21/25 (81%) patients, respectively, and it was common for patients to have more than one abnormality. Presence of 22q11 deletion was associated with longer duration of mechanical ventilation (9.1 vs 4.3 d; p = 0.001), use of noninvasive positive pressure support (13 vs 6 d; p = 0.001), and longer hospital stays (30 vs 14 d; p = 0.002). These outcomes were worse when compared with patients with known airway abnormalities who did not have 22q11 deletion.CONCLUSIONS: Preexisting upper and lower airway pathologies are common in patients with a chromosome 22q11 deletion who undergo pulmonary artery reconstruction surgery. Despite similar postoperative hemodynamics and outcomes as their counterparts without 22q11 deletion, 22q11 deletion is associated with more postoperative respiratory complications not entirely explained by preexisting airway abnormalities.

    View details for DOI 10.1097/PCC.0000000000002921

    View details for PubMedID 35213412

  • Relation Between Pulmonary Artery Pressures Measured Intraoperatively and at One-Year Catheterization After Unifocalization and Repair of Tetralogy with Major Aortopulmonary Collateral Arteries. Seminars in thoracic and cardiovascular surgery Ma, M., Peng, L. F., Zhang, Y., Wise-Faberowski, L., Martin, E., Hanley, F. L., McElhinney, D. B. 1800

    Abstract

    To assess the relationships between pulmonary artery (PA) pressure and the PA:aortic systolic pressure ratio measured intraoperatively and at surveillance catheterization in patients achieving complete unifocalization and repair for tetralogy of Fallot with major aortopulmonary collateral arteries (TOF/MAPCAs). This was a single-center retrospective cohort analysis of all patients who underwent complete repair of TOF/MAPCAs from 2002-2019 and received a postoperative surveillance catheterization at our center 6-24 months after surgery. Associations between intraoperative and catheter hemodynamic data were analyzed. 163 patients were included. Median systolic PA pressure was 30 (quartiles 26, 35) and 35 (28, 42) mmHg intraoperatively and at catherization respectively; systolic aortic pressure 90 (86, 100) and 84 (76, 92); and PA:aortic pressure ratio was 0.33 (0.28, 0.40) and 0.41 (0.34, 0.49). Moderate correlation was found between the intraoperative and catheter-based hemodynamics, with the majority of systolic PA pressures within 10mmHg and PA:Ao systolic ratios within 0.1. Changes in the ratio were influenced to a similar degree by differences in PA and aortic pressures. Surgical and/or catheter reinterventions were more common in patients with both higher intraoperative PA systolic pressure and PA:aortic systolic ratios and in those with greater discrepancy between intraoperative and catheterization values. PA systolic pressure and the PA:aortic systolic pressure ratio measured immediately after repair remain useful metrics for assessing the initial operative PA reconstruction, and as indicators of longer term hemodynamics. Initially elevated and subsequently discrepant PA systolic pressure and PA:aortic systolic pressure ratios were associated with higher rates of reintervention. (Figure 7).

    View details for DOI 10.1053/j.semtcvs.2022.01.004

    View details for PubMedID 35092847

  • A case of acquired von Willebrand disease in severe pediatric pulmonary hypertension contributing to bleeding following reverse Potts shunt. Pulmonary Circulation Sullivan, R. T., Lo, C., Martin, E., Kameny, R. J., Hopper, R. K. 2022; 12 (e12042)

    View details for DOI 10.1002/pul2.12042

  • A case of acquired von Willebrand disease in severe pediatric pulmonary hypertension contributing to bleeding following reverse Potts shunt. Pulmonary circulation Sullivan, R. T., Lo, C., Martin, E., Kameny, R. J., Hopper, R. K. 2022; 12 (1): e12042

    Abstract

    The reverse Potts shunt is increasingly used as a palliative measure for end-stage pulmonary arterial hypertension (PAH) as a means to offload the right ventricle and improve functional status. This case report describes a child who developed significant hemothorax after reverse Potts shunt that required surgical exploration, blood product administration, and prolonged intensive care hospitalization. Despite lack of preoperative bleeding symptoms, testing revealed acquired von Willebrand disease (aVWD), with subsequent resolution of bleeding. Alterations in von Willebrand factor, including aVWD, have been reported in children with severe PAH but have not previously been associated with bleeding after reverse Potts shunt procedure. As bleeding is a recognized postoperative morbidity in PAH patients undergoing reverse Potts shunt, we highlight a potential role for preoperative testing for aVWD as perioperative factor replacement therapy may improve postoperative outcomes.

    View details for DOI 10.1002/pul2.12042

    View details for PubMedID 35506098

    View details for PubMedCentralID PMC9052962

  • Implantable Cardioverter Defibrillators in Infants and Toddlers: Indications, Placement, Programming, and Outcomes. Circulation. Arrhythmia and electrophysiology Zahedivash, A., Hanisch, D., Dubin, A. M., Trela, A., Chubb, H., Motonaga, K., Goodyer, W., Maeda, K., Reinhartz, O., Ma, M., Martin, E., Ceresnak, S. 2022: CIRCEP121010557

    Abstract

    Limited data exist regarding implantable cardioverter defibrillator (ICD) usage in infants and toddlers. This study evaluates ICD placement indications, procedural techniques, programming strategies, and outcomes of ICDs in infants and toddlers.This is a single-center retrospective review of all patients ≤3 years old who received an ICD from 2009 to 2021.Fifteen patients received an ICD at an age of 1.2 years (interquartile range [IQR], 0.1-2.4; 12 [80%] women; weight, 8.2 kg [IQR, 4.2-12.6]) and were followed for a median of 4.28 years (IQR, 1.40-5.53) or 64.2 patient-years. ICDs were placed for secondary prevention in 12 patients (80%). Diagnoses included 8 long-QT syndromes (53%), 4 idiopathic ventricular tachycardias/ventricular fibrillations (VFs; 27%), 1 recurrent ventricular tachycardia with cardiomyopathy (7%), 1 VF with left ventricular noncompaction (7%), and 1 catecholaminergic polymorphic ventricular tachycardia (7%). All implants were epicardial, with a coil in the pericardial space. Intraoperative defibrillation safety testing was attempted in 11 patients (73%), with VF induced in 8 (53%). Successful restoration of sinus rhythm was achieved in all tested patients with a median of 9 (IQR, 7.3-11.3) J or 0.90 (IQR, 0.68-1.04) J/kg. Complications consisted of 1 postoperative chylothorax and 3 episodes of feeding intolerance. VF detection was programmed to 250 (IQR, 240-250) ms with first shock delivering 10 (IQR, 5-15) J or 1.1 (IQR, 0.8-1.4) J/kg. Three patients (20%) received appropriate shocks for ventricular tachycardia/VF. No patient received an inappropriate shock. There were 2 (13%) ventricular lead fractures (at 2.6 and 4.2 years post-implant), 1 (7%) pocket-site infection, and 2 (13%) generator exchanges. All patients were alive, and 1 patient (7%) received a heart transplant.ICDs can be safely and effectively placed for sudden death prevention in infants and toddlers with good midterm outcomes.

    View details for DOI 10.1161/CIRCEP.121.010557

    View details for PubMedID 35089800

  • INTRA-OPERATIVE AUGMENTED REALITY GUIDANCE FOR COMPLEX PULMONARY ARTERY REPAIR, A STEP TOWARD PRECISION SURGERY Chan, F., Aguirre, S., Martin, E., Ma, M., Hanley, F. ELSEVIER SCIENCE INC. 2021: 3239
  • Commentary: The time for last-resort measures-be prepared JTCVS TECHNIQUES Martin, E., Maeda, K. 2020; 3: 216-217
  • Commentary: The time for last-resort measures-be prepared. JTCVS techniques Martin, E., Maeda, K. 2020; 3: 216-217

    View details for DOI 10.1016/j.xjtc.2020.06.040

    View details for PubMedID 34317877

    View details for PubMedCentralID PMC8303049

  • Surgical repair of coronary artery ostial stenosis in patients with Williams and elastin arteriopathy syndromes. The Journal of thoracic and cardiovascular surgery Mainwaring, R. D., Collins, R. T., Patrick, W. L., Martin, E., MacMillen, K. L., Hanley, F. L. 2020

    Abstract

    OBJECTIVE: Patients with Williams and elastin arteriopathy syndromes often have similar cardiac phenotypes characterized by supravalvar aortic stenosis (SVAS), peripheral pulmonary artery stenosis (PPAS), and coronary artery ostial stenosis (CAOS). SVAS and/or PPAS result in a marked increase in myocardial oxygen demand, whereas CAOS may limit myocardial oxygen supply. This combination predisposes to myocardial ischemic events and sudden cardiac arrest. The purpose of this study was to review our experience with the surgical repair of CAOS in patients with Williams and elastin arteriopathy syndromes.METHODS: This was a retrospective review of 16 patients with Williams (n=11) or elastin arteriopathy (n=5) who underwent surgical repair of CAOS as a concomitant procedure with SVAS and/or PPAS repair. Eleven patients had moderate or severe SVAS, and 10 had PPAS. The median age at surgery was 9months (range, 3-108months).RESULTS: Seven patients had repair of the left main and right coronary ostia, 6 the left main, and 3 the right coronary ostium. Median duration of aortic crossclamp was 56minutes and cardiopulmonary bypass time was 454minutes. The median SVAS gradient decreased from 70 to 12mm Hg and pulmonary artery pressure decreased from 120 to 30mm Hg. There was 1 operative mortality (6%). The remaining 15 patients were discharged from the hospital and are alive at a median of 17months' follow-up.CONCLUSIONS: The data demonstrate that patients with Williams and elastin arteriopathy syndromes presenting with SVAS and/or PPAS plus CAOS can undergo successful repair of all hemodynamic issues simultaneously.

    View details for DOI 10.1016/j.jtcvs.2020.08.070

    View details for PubMedID 32977964

  • Surgical repair of peripheral pulmonary artery stenosis in patients without williams or alagille syndromes. Seminars in thoracic and cardiovascular surgery Martin, E. n., Mainwaring, R. D., Collins, R. T., MacMillen, K. L., Hanley, F. L. 2020

    Abstract

    Peripheral pulmonary artery stenosis (PPAS) is a relatively rare form of congenital heart disease typically associated with genetic syndromes, such as Williams or Alagille syndromes. However, some patients present with severe stenosis without associated syndromes. The purpose of the study was to review our surgical experience in such patients. This was a retrospective review of 30 patients who underwent surgical repair for peripheral pulmonary artery stenosis. Concomitant anatomical diagnoses in 20 patients (67%) included: supravalvar aortic stenosis (n=8), tetralogy of Fallot (n=4), d-transposition of the great arteries (n=2), truncus arteriosus (n=2), hypoplastic left heart syndrome (n=2), ventricular septal defect (n=1), and patent ductus arteriosus (n=1). Additional medical diagnoses in 15 patients (50%) included: elastin arteriopathy (n=9), pulmonary artery calcinosis (n=1), arterial tortuosity syndrome (n=1), DiGeorge syndrome (n=1) and Noonan syndrome (n=1). Median age at surgery was 3.6 years (IQR 1.6-7.4 years). Seventeen patients (57%) had prior cardiac operations, and 16 patients (53%) previously underwent percutaneous intervention. With surgery, mean right ventricle-to-aortic systolic pressure ratio decreased from 0.95±0.2 to 0.28±0.08 (p<0.0001). Median duration of cardiopulmonary bypass was 369 minutes. There was 100% survival to hospital discharge, with no mortality at mean follow-up of 2.3 years. No patient required reoperation, while 4 underwent balloon dilation. Freedom from pulmonary artery catheter-based reintervention was 95% and 80% at 12 and 36 months, respectively. Patients with peripheral pulmonary artery stenosis without either Williams or Alagille syndrome can successfully undergo surgical repair with a significant reduction in right ventricle-to-aortic pressure ratios.

    View details for DOI 10.1053/j.semtcvs.2020.01.003

    View details for PubMedID 31958550