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Dive into the research topics where Charles Nyman is active.

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Featured researches published by Charles Nyman.


Anesthesia & Analgesia | 2012

Does rotational thromboelastometry (ROTEM) improve prediction of bleeding after cardiac surgery

Grace C. Lee; Adrienne M. Kicza; Kuang-Yu Liu; Charles Nyman; Richard M. Kaufman; Simon C. Body

BACKGROUND: Coagulopathy and massive bleeding are severe complications of cardiac surgery, particularly in procedures requiring prolonged cardiopulmonary bypass (CPB). There is huge variability in transfusion practices across hospitals and providers in cross-sectional studies. This variability may indicate unguided decision-making, perhaps attributable to lack of reliable, predictive laboratory testing of coagulopathy to guide transfusion practice. Rotational thromboelastometry (ROTEM) measures multiple coagulation parameters and may provide value from its ease of use, rapid results, and measurement of several steps in the coagulation pathway. Yet, the predictive value and utility of ROTEM remains unclear. In this study, we investigated ROTEMs predictive value for chest tube drainage after cardiac surgery. METHODS: Three hundred twenty-one patients undergoing cardiac surgery involving CPB were enrolled. Patient data were obtained from medical records, including chest tube output (CTO) from post-CPB through the first 8 postoperative hours. Perioperative and postoperative blood samples were collected for ROTEM analysis. Three measures of CTO were used as the primary end points for assessing coagulopathy: (i) continuous CTO; (ii) CTO dichotomized at 600 mL (75th percentile); and (iii) CTO dichotomized at 910 mL (90th percentile). Clinical and hematological variables, excluding ROTEM data, that were significantly correlated (P < 0.05) with continuous CTO were included in a stepwise regression model (model 1). An additional model that contained ROTEM variables in addition to the variables from model 1 was created (model 2). Significance in subsequent analyses was declared at P < 0.0167 to account for the 3 CTO end points. Net reclassification index was used to assess overall value of ROTEM data. RESULTS: For continuous CTO, ROTEM variables improved the models predictive ability (P < 0.0001). For CTO dichotomized at 600 mL (75th percentile), ROTEM did not improve the area under the receiver operating characteristic curve (AUC) (P = 0.03). Similarly, for CTO dichotomized at 910 mL (90th percentile), ROTEM did not improve the AUC (P = 0.23). Net reclassification index similarly indicated that ROTEM results did not improve overall classification of patients (P = 0.12 for CTO ≥600 mL; P = 0.08 for CTO ≥910 mL). CONCLUSIONS: These results suggest that ROTEM data do not substantially improve a models ability to predict chest tube drainage, beyond frequently used clinical and laboratory parameters. Although several ROTEM parameters were individually associated with CTO, they did not significantly improve goodness of fit when added to statistical models comprising only clinical and routine laboratory parameters. ROTEM does not seem to improve prediction of chest tube drainage after cardiac surgery involving CPB, although its use in guiding transfusion during cardiac surgery remains to be determined.


Anesthesia & Analgesia | 2016

A Multicenter Pilot Study Assessing Regional Cerebral Oxygen Desaturation Frequency During Cardiopulmonary Bypass and Responsiveness to an Intervention Algorithm.

Balachundhar Subramanian; Charles Nyman; Maria D. Fritock; Rebecca Y. Klinger; Roman M. Sniecinski; Philip Roman; Julie L. Huffmyer; Michelle Parish; Gayane Yenokyan; Charles W. Hogue

BACKGROUND:The purpose of this multicenter pilot study was to: (1) determine the frequency of regional cerebral oxygen saturation (rScO2) desaturations during cardiac surgery involving cardiopulmonary bypass (CPB); (2) evaluate the accuracy of clinician-identified rScO2 desaturations compared with those recorded continuously during surgery by the near-infrared spectroscopy (NIRS) monitor; and (3) assess the effectiveness of an intervention algorithm for reversing rScO2 desaturations. METHODS:Two hundred thirty-five patients undergoing coronary artery bypass graft and/or valvular surgery were enrolled at 8 US centers in this prospective observational study. NIRS (Invos™ 5100C; Covidien) was used to monitor rScO2 during surgery. The frequency and magnitude of rScO2 decrements >20% from preanesthesia baseline were documented, and the efficacy of a standard treatment algorithm for correcting rScO2 was determined. The data from the NIRS monitor were downloaded at the conclusion of surgery and sent to the coordinating center where the number of clinician-identified rScO2 desaturation events was compared with the number detected by the NIRS monitor. RESULTS:The average rScO2 obtained at baseline (mean ± SD, 61% ± 11%; 99% confidence interval, 57%–65%) and during CPB (62% ± 14%; 57%–67%) was not different. However, rScO2 after separation from CPB (56% ± 11%; 53%–60%) was lower than measurements at baseline and during CPB (P < 0.001). During CPB, rScO2 desaturations occurred in 61% (99% confidence interval, 50%–75%) of patients. The area under the curve for product of magnitude and duration of the rScO2 was (mean ± SD, 145.2; 384.8% × min). Clinicians identified all patients with an rScO2 desaturation but identified only 340 (89.5%) of the 380 total desaturation events. Of the 340 clinician-identified rScO2 desaturation events, 115 resolved with usual clinical care before implementation of the treatment algorithm. For the remaining 225 events, the treatment algorithm resulted in resolution of the rScO2 desaturation in all but 18 patients. CONCLUSIONS:This multicenter pilot study found that 50% to 75% of patients undergoing cardiac surgery experience one or more rScO2 desaturations during CPB. Nearly 10% of desaturation events were not identified by clinicians, suggesting that appropriate alarming systems should be adopted to alert clinicians of such events. The intervention algorithm was effective in reversing clinically identified rScO2 desaturations in the majority of events.


Jacc-cardiovascular Imaging | 2017

Leaflet Thrombosis in Surgically Explanted or Post-Mortem TAVR Valves

Fernanda Marinho Mangione; Tannas Jatene; Alexandra Gonçalves; Gregory A. Fishbein; Richard N. Mitchell; Marc P. Pelletier; Tsuyoshi Kaneko; Pinak B. Shah; Charles Nyman; Douglas Shook; Ron Blankstein; Robert F. Padera; Deepak L. Bhatt

Leaflet thrombosis is currently one of the greatest concerns related to transcatheter aortic valve replacement (TAVR). Symptomatic valve thrombosis is a rare occurrence, but reduced leaflet motion, diagnosed by computed tomography, seems to be a more common finding [(1)][1]. We screened our


Journal of The American Society of Echocardiography | 2018

Transcatheter Mitral Valve Repair Using the Edge-to-Edge Clip

Charles Nyman; G. Burkhard Mackensen; Srdjan Jelacic; Stephen H. Little; Thomas W. Smith; Feroze Mahmood

Percutaneous intervention for mitral valve (MV) disease has been established as an alternative to open surgical MV repair in patients with prohibitive surgical risk. Multiple percutaneous approaches have been described and are in various stages of development. Edge-to-edge leaflet plication with the MitraClip (Abbott, Menlo Park, CA) is currently the only Food and Drug Administration-approved device specifically for primary or degenerative lesions. Use of the edge-to-edge clip for secondary mitral regurgitation is currently under investigation and may result in expanded indications. Echocardiography has significantly increased our understanding of the anatomy of the MV and provided us with the ability to classify and quantify the associated mitral regurgitation. For percutaneous interventions of the MV, transesophageal echocardiography imaging is used for patient screening, intraprocedural guidance, and confirmation of the result. Optimal outcomes require the echocardiographer and the proceduralist to have a thorough understanding of intra-atrial septal and MV anatomy, as well as an appreciation for the key points and potential pitfalls of each of the procedural steps. With increasing experience, more complex valvular pathology can be successfully percutaneously treated. In addition to two-dimensional echocardiography, advances in three-dimensional echocardiography and fusion imaging will continue to support the refinement of current technologies, the expansion of clinical applications, and the development of novel devices.


Circulation-cardiovascular Interventions | 2018

Balloon Fracture of a Surgical Mitral Bioprosthesis During Valve-in-Valve Transcatheter Mitral Valve Replacement: First-in-Human Report

Tsuyoshi Kaneko; Bryan Piccirillo; Harsh Golwala; Agnieszka Trzcinka; Charles Nyman; Douglas Shook; Marc P. Pelletier; Natalia Berry; Piotr Sobieszczyk; Pinak B. Shah

A 65-year-old female underwent coronary artery bypass grafting plus mitral valve replacement (MVR) with a 25-mm Epic bioprosthesis (Abbott, Santa Ana, CA). Postoperatively, she was readmitted with congestive heart failure exacerbation. Transthoracic echocardiogram showed mean prosthetic gradient of 18 mm Hg raising concern for early valve deterioration. She was deemed high risk for surgery. Therefore, transseptal transcatheter valve-in-valve MVR with a 23-mm Sapien3 valve (Edwards Lifesciences, Irvine, CA) was performed 15 months post-MVR. Postimplantation …


Interactive Cardiovascular and Thoracic Surgery | 2018

Novel fast-track recovery protocol for alternative access transcatheter aortic valve replacement: application to non-femoral approaches

Ahmed Kolkailah; Sameer A. Hirji; Julius I. Ejiofor; Fernando Ramirez-Del Val; Jiyae Lee; Anthony Norman; Siobhan McGurk; Sadiqa Mahmood; Douglas Shook; Kamen V. Vlassakov; Charles Nyman; Pinak B. Shah; Marc P. Pelletier; Tsuyoshi Kaneko

OBJECTIVES Although the transfemoral approach for transcatheter aortic valve replacement is the preferred choice, alternative access remains indicated for inadequate iliofemoral vessels. We report the successful implementation of a novel fast-track (FT) protocol for patients undergoing alternative access transcatheter aortic valve replacement compared with conventional controls. METHODS Between September 2014 and January 2017, 31 and 23 patients underwent alternative access transcatheter aortic valve replacement under FT and pre-fast-track (p-FT) protocols, respectively. Comparisons of outcomes (in terms of mortality, complications, readmissions and resource utilization) were made before and after the implantation of the FT protocol in September 2015. RESULTS Overall, mean age was 78.7 years in FT and 79.6 years in p-FT patients (P = 0.71). There were no significant differences in procedural (3.2% vs 13.0%, P = 0.301) or 90-day mortality (3.2% vs 17.4%, P = 0.151) between the FT and p-FT groups, respectively. Compared with p-FT patients, FT patients had significantly shorter intensive care unit stays (12 h vs 27 h, P = 0.006) and a trend towards more discharges within 3 days (41.9% vs 17.4%, P = 0.081). Resource utilization analyses projected a 56% and 17% reduction in the mean intensive care unit time (hours) per 100 patients and the total length of stay (days) per 100 patients, respectively, with respect to the FT approach. CONCLUSIONS This pilot study demonstrates the feasibility and safety of the novel FT protocol for alternative access transcatheter aortic valve replacement, resulting in shorter intensive care unit stays, without increasing procedural complications or readmissions. With the expected increase in transcatheter aortic valve replacement utilization, FT protocols should be integrated with a multidisciplinary heart team approach to enhance patient recovery and optimize resource utilization.


Journal of the American College of Cardiology | 2016

TCT-726 Aortic Valve Replacement in Patients With Prior Mediastinal Radiation: Transcatheter Vs Surgical Approach.

Julius I. Ejiofor; Anju Nohria; Anthony Norman; Siobhan McGurk; Douglas Shook; Charles Nyman; Piotr Sobieszczyk; Pinak B. Shah; Prem S. Shekar; Marc P. Pelletier; Tsuyoshi Kaneko

TCT-726 Aortic Valve Replacement in Patients With Prior Mediastinal Radiation: Transcatheter Vs Surgical Approach Julius I. Ejiofor, Anju Nohria, Anthony Norman, Siobhan McGurk, Charles Nyman, Douglas Shook, Piotr Sobieszczyk, Pinak Shah, Prem Shekar, Marc Pelletier, Tsuyoshi Kaneko Scripps Clinic, Boston, Massachusetts, United States; Austin Health; asf; Exponent; John H Stroger, Jr. Hospital of Cook County; Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States; University of Massachusetts Medical School; Unknown, Brookline, Massachusetts, United States; Mount Sinai Beth Israel; Mount Sinai Beth Israel, Boston, Massachusetts, United States; Brigham and Women’s Hospital, Boston, Massachusetts, United States


Jacc-cardiovascular Imaging | 2017

Identifying Patients at Risk for LVOT Obstruction in Mitral Valve-in-Valve Implantation.

Ross Hanson; Charles Nyman; Douglas Shook; Chuan-Chin Huang; Tsuyoshi Kaneko; Pinak B. Shah; John Fox; Stanton K. Shernan


The Cardiology | 2017

Transthoracic Echocardiography to Assess Aortic Regurgitation after TAVR: A Comparison with Periprocedural Transesophageal Echocardiography.

Alexandra Gonçalves; Charles Nyman; David R. Okada; Avinainder Singh; Jeffrey Swanson; Michael K. Cheezum; Michael L. Steigner; Marcelo F. Di Carli; Scott D. Solomon; Pinak B. Shah; Deepak L. Bhatt; Douglas Shook; Ron Blankstein


Jacc-cardiovascular Interventions | 2018

Transcatheter Aortic Valve Replacement for Bioprosthetic Aortic Stenosis in Pregnancy

Natalia Berry; Neal Sawlani; Katherine Economy; Douglas Shook; Charles Nyman; Michael N. Singh; Marc P. Pelletier; Piotr Sobieszczyk; Tsuyoshi Kaneko; Pinak B. Shah

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Douglas Shook

Brigham and Women's Hospital

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Pinak B. Shah

Brigham and Women's Hospital

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Tsuyoshi Kaneko

Brigham and Women's Hospital

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Marc P. Pelletier

Brigham and Women's Hospital

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Piotr Sobieszczyk

Brigham and Women's Hospital

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Siobhan McGurk

Brigham and Women's Hospital

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Ahmed Kolkailah

Brigham and Women's Hospital

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Anthony Norman

Brigham and Women's Hospital

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Deepak L. Bhatt

Brigham and Women's Hospital

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