Bio

Clinical Focus

  • Cardiovascular Surgery
  • Thoracic Surgery

Academic Appointments

Professional Education

  • Board Certification: American Board of Thoracic Surgery, Thoracic Surgery (2010)
  • Fellowship: Loma Linda University General Surgery Residency (2008) CA
  • Board Certification: American Board of Surgery, General Surgery (2006)
  • Residency: University of North Dakota Office of the Registrar (2005) ND
  • Residency: St Vincent's Hospital and New York Medical College (2001) NY
  • Medical Education: St Georges University School of Medicine Grenada West Indies (2000) NY West Indies
  • Board Certification, American Board of Thoracic Surgery, Thoracic Surgery (2010)

Contact

  • Pediatric and Adult Congenital Cardiothoracic Surgery Office 2800 L St Ste 110 Sacramento, CA 95816
    • Tel: (916) 340-0111
    Fax: (916) 340-0121

Links

Research & Scholarship

Clinical Trials

  • Left Atrial Pressure Monitoring to Optimize Heart Failure Therapy Not Recruiting

    The purpose of this clinical study is to evaluate the safety and clinical effectiveness of use of a physician-directed, patient self-management system, guided by left atrial pressure measurements, for use in patients with heart failure. The system allows patients to adjust their HF medications daily based on a physician-directed prescription plan and their current HF status, similar to the manner in which diabetes patients manage their insulin therapy. The goal of the LAPTOP-HF study is to demonstrate reductions in episodes of worsening heart failure (HF) and hospitalizations in patients who are managed with the left atrial pressure (LAP) management system (treatment group) versus those who receive only the current standard of care (control group).

    Stanford is currently not accepting patients for this trial.

    View full details

Publications

All Publications

  • Is Continuous Flow Superior to Pulsatile Flow in Single Ventricle Mechanical Support? Results from a Large Animal Pilot Study. ASAIO journal (American Society for Artificial Internal Organs : 1992) Fujii, Y., Ferro, G., Kagawa, H., Centola, L., Zhu, L., Ferrier, W. T., Talken, L., Riemer, R. K., Maeda, K., Nasirov, T., Hodges, B., Amirriazi, S., Lee, E., Sheff, D., May, J., May, R., Reinhartz, O. ; 61 (4): 443?47

    Abstract

    Durable mechanical support in situations of physiologic single ventricle has been met with little success so far, particularly in small children. We created an animal model to investigate whether pulsatile or continuous flow would be superior. Three 1 month old sheep (10-16?kg) were instrumented. Via sternotomy and with cardiopulmonary bypass, a large ventricular septal defect and atrial septal defect were created. The left ventricle was cannulated using a Berlin Heart inflow cannula. This was connected sequentially to a continuous flow device (Thoratec HeartMate X, Pleasanton, CA) and to a pulsatile device (Berlin Heart Excor, The Woodlands, TX). Outflow was via a Y-graft to both aorta and pulmonary artery, striving for equal flow to both. Atrial filling pressures were controlled with volume infusions over a wide range. Under comparable loading conditions, significantly higher maximum flow was obtained by HeartMate X than by Excor (4.95?±?1.27?L/min [range, 3.84-6.34?L/min] for HeartMate X vs. 1.80?±?0.85?L/min [range, 1.01-2.7?L/min] for Excor; p < 0.05). Judging from this limited animal study, in single ventricle scenarios, continuous flow devices may achieve higher pump flows than pulsatile devices when provided with similar filling pressures. Their clinical use should be investigated. More extensive experimental studies are needed.

    View details for PubMedID 25794246

  • Aortic or Pulmonary Valved Homograft Right Ventricle to Pulmonary Artery Conduit in the Norwood Procedure. World journal for pediatric & congenital heart surgery Nasirov, T., Maeda, K., Reinhartz, O. 2019; 10 (4): 499?501

    Abstract

    BACKGROUND: Several modifications of the Norwood procedure utilizing valved right ventricle to pulmonary artery conduits have recently been reported. Our group has been using aortic or pulmonary valved homografts combined with PTFE tube grafts for now 16 years.METHODS: In this report, we review our technique in detail and describe any changes that have occurred over the years. We provide detailed illustrations of our preferred surgical technique, report outcome data, and compare it to the other conduit options available.RESULTS: Between 2006 and 2015, 130 stage I Norwood procedures were performed at our institution, 100 of them using valved conduits. Our technique is described and illustrated in detail. Early mortality was 15%. Postoperative percutaneous intervention on the conduit was required in 29% of cases.CONCLUSIONS: While a randomized trial comparing different valved conduits is lacking, we believe a composite conduit made from homograft aortic or pulmonary valves and PTFE tube grafts is an excellent choice in stage I Norwood procedure.

    View details for DOI 10.1177/2150135119842865

    View details for PubMedID 31307304

  • Analysis of achieving an "ideal" outcome following midline unifocalization. Asian cardiovascular & thoracic annals Mainwaring, R. D., Patrick, W. L., Rosenblatt, T. R., Nasirov, T., Kamra, K., Hanley, F. L. 2018: 218492318814079

    Abstract

    OBJECTIVE: Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries is a complex form of congenital heart disease. Midline unifocalization has been developed for the surgical treatment of this condition. There are 3 outcome measures that determine long-term success: patients are alive, patients have achieved complete repair (i.e. ventricular septal defect closure), and patients have a relatively low right ventricle-to-aortic pressure ratio (<0.45). However, to date, no studies have combined these 3 outcome measures to analyze the likelihood of achieving an ideal outcome.METHODS: This was a retrospective review of 255 patients who underwent midline unifocalization for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. The median age at unifocalization was 4.5 months.RESULTS: Two hundred thirty-five (92%) patients were alive at a mean follow-up of 5.3 years. Two hundred and seventeen (85%) patients underwent single-stage complete repair, and 38 (15%) had an initial unifocalization and shunt. Twenty-four of the 38 palliated patients have subsequently undergone repair. Thus 241 (94%) patients ultimately achieved complete repair. Of the 241 patients who were repaired, 219 (86%) had a right ventricle-to-aortic peak systolic pressure ratio <0.45. Combining these outcome measures, 77% of patients achieved an ideal outcome at one month, 73% at 6 months, 76% at one year, and 80% at 4 years.CONCLUSIONS: Most (80%) patients can achieve all 3 measures of favorable outcome at 4 years following midline unifocalization. We speculate that this will be a favorable portend for the future of these patients.

    View details for DOI 10.1177/0218492318814079

    View details for PubMedID 30417684

  • An Alternative Approach by HVAD Ventricular Assist Device in Hypertrophic Cardiomyopathy. The Annals of thoracic surgery Maeda, K., Nasirov, T., Rosenthal, D. N., Dykes, J. C. 2018

    Abstract

    Hypertrophic cardiomyopathy is known to be difficult to support by left ventricular assist device due to the small ventricular cavity and inadequate drainage. Therefore, instead of cannulating on the left ventricular apex, Heartware HVAD ventricular device was connected to the left atrium through right atrium onto atrial septum using ringed Goretex interposition graft. The patient has been discharged home after VAD implant and underwent successful heart transplant after 111 days of support without any complications including any thromboembolic events. This new trans-atrial left atrial cannulation technique can be an alternative approach for VAD cannulation in hypertrophic cardiomyopathy. It can be safely performed with the Heartware HVAD.

    View details for PubMedID 29807009

  • Biatrial connection of partial anomalous pulmonary venous return. Asian cardiovascular & thoracic annals Watanabe, N., Fallah, H., Pugh, C., Nasirov, T. 2017: 218492317704526-?

    Abstract

    We describe an extremely rare case of partial anomalous pulmonary venous return in a 3-year-old boy with an abnormal connection between the right upper pulmonary vein and the right middle pulmonary vein, which created biatrial communication hemodynamically. Patch closure on the orifice of the right upper pulmonary vein was performed to avoid distortion or kinking of the right pulmonary veins and the connection.

    View details for DOI 10.1177/0218492317704526

    View details for PubMedID 28361581

  • Is Continuous Flow Superior to Pulsatile Flow in Single Ventricle Mechanical Support? Results from a Large Animal Pilot Study ASAIO JOURNAL Fujii, Y., Ferro, G., Kagawa, H., Centola, L., Zhu, L., Ferrier, W. T., Talken, L., Riemer, R. K., Maeda, K., Nasirov, T., Hodges, B., Amirriazi, S., Lee, E., Sheff, D., May, J., May, R., Reinhartz, O. 2015; 61 (4): 443-447

    Abstract

    Durable mechanical support in situations of physiologic single ventricle has been met with little success so far, particularly in small children. We created an animal model to investigate whether pulsatile or continuous flow would be superior. Three 1 month old sheep (10-16?kg) were instrumented. Via sternotomy and with cardiopulmonary bypass, a large ventricular septal defect and atrial septal defect were created. The left ventricle was cannulated using a Berlin Heart inflow cannula. This was connected sequentially to a continuous flow device (Thoratec HeartMate X, Pleasanton, CA) and to a pulsatile device (Berlin Heart Excor, The Woodlands, TX). Outflow was via a Y-graft to both aorta and pulmonary artery, striving for equal flow to both. Atrial filling pressures were controlled with volume infusions over a wide range. Under comparable loading conditions, significantly higher maximum flow was obtained by HeartMate X than by Excor (4.95?±?1.27?L/min [range, 3.84-6.34?L/min] for HeartMate X vs. 1.80?±?0.85?L/min [range, 1.01-2.7?L/min] for Excor; p < 0.05). Judging from this limited animal study, in single ventricle scenarios, continuous flow devices may achieve higher pump flows than pulsatile devices when provided with similar filling pressures. Their clinical use should be investigated. More extensive experimental studies are needed.

    View details for DOI 10.1097/MAT.0000000000000220

    View details for Web of Science ID 000358285100013

  • Hemodynamic Monitoring of Large Animal Chronic Studies After Median Sternotomy: Experiences With Different Telemetric Physiological Devices ASAIO JOURNAL Fujii, Y., Pitsillides, K., Ferro, G., Kagawa, H., Centola, L., Kinouchi, K., Zhu, L., Ferrier, W. T., Talken, L., Nasirov, T., Riemer, R. K., Reinhartz, O. 2015; 61 (3): 332-338

    Abstract

    Telemetric physiological monitoring systems (TPMS) have enabled accurate continuous measurement of animal blood pressures and flows. However, few studies describe approaches for use of TPMS in the great vessels or inside the heart. We describe our initial experiences using two types of TPMSs. Twelve lambs (20-37 kg) underwent sternotomy. Two lambs were not instrumented and were killed at 14 days to confirm normal sternal wound healing (sham group, n = 2). Ten lambs underwent placement of either standard indwelling pressure-monitoring catheter and perivascular-flow-probe (CFP group, n = 3) or TPMS implantation (TPMS group, n = 7). The TPMS used were EG1-V3S2T-M2 (EG1, n = 5; Transonic Endogear Inc.) and Physio Tel Digital L21 (PTD, n = 2; Data Sciences Inc.). Two deaths because of respiratory problems occurred in TPMS group, attributed to lung compression by the implanted device. In TPMS group, more consistent trends of blood pressures and flows were recorded, and management of animals was easier and less labor-intensive. Comparing the two TPMSs, the initiation and renewal costs for each case was $28 K vs. $20 K and $1,700 vs. $0, (PTD versus EG1, respectively). In conclusion, TPMS implantation was feasible via median sternotomy in lambs. Telemetric physiological monitoring systems significantly improve reliability of hemodynamic monitoring in chronic survival animal study. EG1 was less costly than PTD.

    View details for DOI 10.1097/MAT.0000000000000202

    View details for Web of Science ID 000353811800018

    View details for PubMedID 25635937

  • Telemetric monitoring of blood flow and pressure in a chronic lamb model Fujji, Y., Centola, L., Kinouchi, K., Zhu, L., Pitsillides, K., Ferrier, W., Talken, L., Nasirov, T., Reinhartz, O., Riemer, R. FEDERATION AMER SOC EXP BIOL. 2014

    View details for Web of Science ID 000346651003001

  • Innominate artery cannulation and antegrade cerebral perfusion for aortic arch reconstruction in infants and children. World journal for pediatric & congenital heart surgery Nasirov, T., Mainwaring, R. D., Reddy, V. M., Sleasman, J., Margetson, T., Hanley, F. L. 2013; 4 (4): 356-361

    Abstract

    Innominate artery cannulation has been widely adopted as a means to perform aortic arch reconstruction with continuous cerebral perfusion in the newborn. Although this technique has been subsequently utilized in infants and children, there is currently no data regarding the safety or efficacy in these older children. The purpose of this study was to review our experience with innominate artery cannulation for aortic arch reconstruction in patients beyond the neonatal period.This was a retrospective review of 42 infants and children who underwent aortic arch reconstruction using the technique of innominate artery cannulation with continuous cerebral perfusion. Of these procedures, 29 (69%) were primary arch reconstructions, while 13 (31%) were aortic arch reoperations. The median age at surgery was 8 months, and 22 patients underwent concomitant intracardiac repairs.There was no operative mortality in this cohort of 42 patients undergoing aortic arch reconstruction. There was also no overt evidence of neurologic injury. Specifically, none of the patients demonstrated a neurologic deficit, clinical seizure, or unexpected delay in regaining a normal state of consciousness. The median duration of antegrade cerebral perfusion was 34 minutes. The median duration of hospital stay was 11 days. No patient required reoperation on the aortic arch with a median of 45-month follow-up.Innominate artery cannulation is a safe and effective technique for aortic arch reconstruction in nonneonates. We conclude that antegrade cerebral perfusion is a useful technique for aortic arch reconstruction in this patient population.

    View details for DOI 10.1177/2150135113497767

    View details for PubMedID 24327627

  • Fetal cardiac intervention: Improved results of fetal cardiac bypass in immature fetuses using the TinyPump device. journal of thoracic and cardiovascular surgery Sebastian, V. A., Ferro, G., Kagawa, H., Nasirov, T., Maeda, K., Ferrier, W. T., Takatani, S., Riemer, R. K., Hanley, F. L., Reddy, V. M. 2013; 145 (6): 1460-1464

    Abstract

    Fetal cardiac surgery is a potential innovative treatment for certain congenital heart defects that have significant mortality and morbidity in utero or after birth, but it has been limited by placental dysfunction after fetal cardiac bypass. We have used the TinyPump device for fetal cardiac bypass in sheep fetuses at 90 to 110 days gestation.Ten mixed-breed pregnant ewes were used over a period of 6 months, and 10 fetuses were placed on bypass for 30 minutes. Five fetuses with a mean gestational age of 104 ± 4.5 days and mean weight of 1.4 ± 0.4 kg were placed on bypass using the TinyPump device, and 5 fetuses with a mean gestational age of 119 ± 4.5 days and mean weight of 3.4 ± 0.4 kg were placed on bypass using the roller head pump. The fetuses were monitored for up to 3 hours after bypass or until earlier demise.Progressive respiratory and metabolic acidosis developed in all fetuses. The TinyPump group had a lower gestational age and weight compared with the roller head pump group. However, the rate of postbypass deterioration in the TinyPump group, as measured with blood gases, was noted to be significantly slower compared with the roller head pump group.We demonstrate the feasibility of the TinyPump device for fetal cardiac bypass in a fetal sheep model. The TinyPump group showed improved results compared with the roller head group despite more immature fetuses. The TinyPump device seems to be a promising device for future studies of fetal cardiac bypass in immature fetal sheep and in primates.

    View details for DOI 10.1016/j.jtcvs.2012.08.014

    View details for PubMedID 22944083

  • Anomalous Aortic Origin of a Coronary Artery: Medium-Term Results After Surgical Repair in 50 Patients ANNALS OF THORACIC SURGERY Mainwaring, R. D., Reddy, V. M., Reinhartz, O., Petrossian, E., Macdonald, M., Nasirov, T., Miyake, C. Y., Hanley, F. L. 2011; 92 (2): 691-697

    Abstract

    Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital heart defect that has been associated with myocardial ischemia and sudden death. Controversies exist regarding the diagnosis, treatment, and long-term recommendations for patients with AAOCA. The purpose of this study is to evaluate the medium-term results of surgical repair for AAOCA.From January 1999 through August 2010, 50 patients underwent surgical repair of AAOCA. The median age at surgery was 14 years (range, 5 days to 47 years). Thirty-one patients had the right coronary originate from the left sinus of Valsalva, 17 had the left coronary originate from the right sinus, and 2 had an eccentric single coronary ostium. Twenty six of the 50 patients had symptoms of myocardial ischemia preoperatively, and 14 patients had associated congenital heart defects. Repair was accomplished by unroofing in 35, reimplantation in 6, and pulmonary artery translocation in 9.There was no operative mortality. The median time of follow-up has been 5.7 years. Two patients were lost to follow-up, and 1 patient required heart transplantation 1 year after AAOCA repair. In the remaining 47 postoperative patients, all have remained free of cardiac symptoms and no one has experienced a sudden death event.The surgical treatment of AAOCA is safe and appears to be highly effective in eliminating ischemic symptoms. These medium-term results are encouraging and suggest that many patients may be able to resume normal activities.

    View details for DOI 10.1016/j.athoracsur.2011.03.127

    View details for Web of Science ID 000293221000050

    View details for PubMedID 21718962

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