IU Indianapolis ScholarWorks :: Browsing by Author "Kawut, Steven M."

Browsing by Author "Kawut, Steven M."

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Assessment of Right Ventricular Function in the Research Setting: Knowledge Gaps and Pathways Forward. An Official American Thoracic Society Research Statement
(American Thoracic Society, 2018-08-15) Lahm, Tim; Douglas, Ivor S.; Archer, Stephen L.; Bogaard, Harm J.; Chesler, Naomi C.; Haddad, Francois; Hemnes, Anna R.; Kawut, Steven M.; Kline, Jeffrey A.; Kolb, Todd M.; Mathai, Stephen C.; Mercier, Olaf; Michelakis, Evangelos D.; Naeije, Robert; Tuder, Rubin M.; Ventetuolo, Corey E.; Vieillard-Baron, Antoine; Voelkel, Norbert F.; Vonk-Noordegraaf, Anton; Medicine, School of Medicine
BACKGROUND: Right ventricular (RV) adaptation to acute and chronic pulmonary hypertensive syndromes is a significant determinant of short- and long-term outcomes. Although remarkable progress has been made in the understanding of RV function and failure since the meeting of the NIH Working Group on Cellular and Molecular Mechanisms of Right Heart Failure in 2005, significant gaps remain at many levels in the understanding of cellular and molecular mechanisms of RV responses to pressure and volume overload, in the validation of diagnostic modalities, and in the development of evidence-based therapies. METHODS: A multidisciplinary working group of 20 international experts from the American Thoracic Society Assemblies on Pulmonary Circulation and Critical Care, as well as external content experts, reviewed the literature, identified important knowledge gaps, and provided recommendations. RESULTS: This document reviews the knowledge in the field of RV failure, identifies and prioritizes the most pertinent research gaps, and provides a prioritized pathway for addressing these preclinical and clinical questions. The group identified knowledge gaps and research opportunities in three major topic areas: 1) optimizing the methodology to assess RV function in acute and chronic conditions in preclinical models, human studies, and clinical trials; 2) analyzing advanced RV hemodynamic parameters at rest and in response to exercise; and 3) deciphering the underlying molecular and pathogenic mechanisms of RV function and failure in diverse pulmonary hypertension syndromes. CONCLUSIONS: This statement provides a roadmap to further advance the state of knowledge, with the ultimate goal of developing RV-targeted therapies for patients with RV failure of any etiology.
Diagnosis and Treatment of Right Heart Failure in Pulmonary Vascular Diseases: A National Heart, Lung, and Blood Institute Workshop
(American Heart Association, 2021) Leopold, Jane A.; Kawut, Steven M.; Aldred, Micheala A.; Archer, Stephen L.; Benza, Ray L.; Bristow, Michael R.; Brittain, Evan L.; Chesler, Naomi; DeMan, Frances S.; Erzurum, Serpil C.; Gladwin, Mark T.; Hassoun, Paul M.; Hemnes, Anna R.; Lahm, Tim; Lima, Joao A. C.; Loscalzo, Joseph; Maron, Bradley A.; Mercer Rosa, Laura; Newman, John H.; Redline, Susan; Rich, Stuart; Rischard, Franz; Sugeng, Lissa; Tang, W. H. Wilson; Tedford, Ryan J.; Tsai, Emily J.; Ventetuolo, Corey E.; Zhou, YouYang; Aggarwal, Neil R.; Xiao, Lei; Medicine, School of Medicine
Right ventricular dysfunction is a hallmark of advanced pulmonary vascular, lung parenchymal, and left heart disease, yet the underlying mechanisms that govern (mal)adaptation remain incompletely characterized. Owing to the knowledge gaps in our understanding of the right ventricle (RV) in health and disease, the National Heart, Lung, and Blood Institute (NHLBI) commissioned a working group to identify current challenges in the field. These included a need to define and standardize normal RV structure and function in populations; access to RV tissue for research purposes and the development of complex experimental platforms that recapitulate the in vivo environment; and the advancement of imaging and invasive methodologies to study the RV within basic, translational, and clinical research programs. Specific recommendations were provided, including a call to incorporate precision medicine and innovations in prognosis, diagnosis, and novel RV therapeutics for patients with pulmonary vascular disease.
The Impact of Pulmonary Hypertension in Preterm Infants with Severe Bronchopulmonary Dysplasia through 1 Year
(Elsevier, 2018-12) Lagatta, Joanne M.; Hysinger, Erik B.; Zaniletti, Isabella; Wymore, Erica M.; Vyas-Read, Shilpa; Yallapragada, Sushmita; Nelin, Leif D.; Truog, William E.; Padula, Michael A.; Porta, Nicolas F. M.; Savani, Rashmin C.; Potoka, Karin P.; Kawut, Steven M.; DiGeronimo, Robert; Natarajan, Girija; Zhang, Huayan; Grover, Theresa R.; Engle, William A.; Murthy, Karna; Pediatrics, School of Medicine
Objectives To assess the effect of pulmonary hypertension on neonatal intensive care unit mortality and hospital readmission through 1 year of corrected age in a large multicenter cohort of infants with severe bronchopulmonary dysplasia. Study design This was a multicenter, retrospective cohort study of 1677 infants born <32 weeks of gestation with severe bronchopulmonary dysplasia enrolled in the Children's Hospital Neonatal Consortium with records linked to the Pediatric Health Information System. Results Pulmonary hypertension occurred in 370 out of 1677 (22%) infants. During the neonatal admission, pulmonary hypertension was associated with mortality (OR 3.15, 95% CI 2.10-4.73, P < .001), ventilator support at 36 weeks of postmenstrual age (60% vs 40%, P < .001), duration of ventilation (72 IQR 30-124 vs 41 IQR 17-74 days, P < .001), and higher respiratory severity score (3.6 IQR 0.4-7.0 vs 0.8 IQR 0.3-3.3, P < .001). At discharge, pulmonary hypertension was associated with tracheostomy (27% vs 9%, P < .001), supplemental oxygen use (84% vs 61%, P < .001), and tube feeds (80% vs 46%, P < .001). Through 1 year of corrected age, pulmonary hypertension was associated with increased frequency of readmission (incidence rate ratio [IRR] = 1.38, 95% CI 1.18-1.63, P < .001). Conclusions Infants with severe bronchopulmonary dysplasia-associated pulmonary hypertension have increased morbidity and mortality through 1 year of corrected age. This highlights the need for improved diagnostic practices and prospective studies evaluating treatments for this high-risk population.
Inhibiting oestrogen signalling in pulmonary arterial hypertension: sex, drugs and research
(European Respiratory Society, 2017-08-03) Lahm, Tim; Kawut, Steven M.; Medicine, School of Medicine
Pulmonary arterial hypertension (PAH) is a sexually dimorphic disease that affects women more than men. Several pre-clinical and clinical studies identified 17β-oestradiol (E2), the most abundant female sex hormone, and/or its metabolite 16α-hydroxyoestrone as disease mediators in PAH (reviewed by Lahm et al. [1], and Foderaro and Venteuolo [2]). A recent case–control study even demonstrated significantly higher levels of E2 in men with PAH compared to controls [3]., Inhibition of oestrogen signalling in PAH is currently being studied clinically but several questions remain http://ow.ly/G7xK30cPN5M
Investigational new drug enabling angiotensin oral-delivery studies to attenuate pulmonary hypertension
(Elsevier, 2020-03) Daniell, Henry; Mangu, Venkata; Yakubov, Bakhtiyor; Park, Jiyoung; Habibi, Peyman; Shi, Yao; Gonnella, Patricia A.; Fisher, Amanda; Cook, Todd; Zeng, Lily; Kawut, Steven M.; Lahm, Tim; Cellular and Integrative Physiology, School of Medicine
Pulmonary arterial hypertension (PAH) is a deadly and uncurable disease characterized by remodeling of the pulmonary vasculature and increased pulmonary artery pressure. Angiotensin Converting Enzyme 2 (ACE2) and its product, angiotensin-(1-7) [ANG-(1-7)] were expressed in lettuce chloroplasts to facilitate affordable oral drug delivery. Lyophilized lettuce cells were stable up to 28 months at ambient temperature with proper folding, assembly of CTB-ACE2/ANG-(1-7) and functionality. When the antibiotic resistance gene was removed, Ang1-7 expression was stable in subsequent generations in marker-free transplastomic lines. Oral gavage of monocrotaline-induced PAH rats resulted in dose-dependent delivery of ANG-(1-7) and ACE2 in plasma/tissues and PAH development was attenuated with decreases in right ventricular (RV) hypertrophy, RV systolic pressure, total pulmonary resistance and pulmonary artery remodeling. Such attenuation correlated well with alterations in the transcription of Ang-(1-7) receptor MAS and angiotensin II receptor AGTRI as well as IL-1β and TGF-β1. Toxicology studies showed that both male and female rats tolerated ~10-fold ACE2/ANG-(1-7) higher than efficacy dose. Plant cell wall degrading enzymes enhanced plasma levels of orally delivered protein drug bioencapsulated within plant cells. Efficient attenuation of PAH with no toxicity augurs well for clinical advancement of the first oral protein therapy to prevent/treat underlying pathology for this disease.
Preoperative plasma club (clara) cell secretory protein levels are associated with primary graft dysfunction after lung transplantation
(Wiley Blackwell (Blackwell Publishing), 2014-02) Shah, Rupal J.; Wickersham, Nancy; Lederer, David J.; Palmer, Scott M.; Cantu, Edward; Diamond, Joshua M.; Kawut, Steven M.; Lama, Vibha N.; Bhorade, Sangeeta; Crespo, Maria; Demissie, Ejigayehu; Sonett, Joshua; Wille, Keith; Orens, Jonathan; Weinacker, Ann; Shah, Pali; Arcasoy, Selim; Wilkes, David S.; Christie, Jason D.; Ware, Lorraine B.; Department of Medicine, IU School of Medicine
Inherent recipient factors, including pretransplant diagnosis, obesity and elevated pulmonary pressures, are established primary graft dysfunction (PGD) risks. We evaluated the relationship between preoperative lung injury biomarkers and PGD to gain further mechanistic insight in recipients. We performed a prospective cohort study of recipients in the Lung Transplant Outcomes Group enrolled between 2002 and 2010. Our primary outcome was Grade 3 PGD on Day 2 or 3. We measured preoperative plasma levels of five biomarkers (CC-16, sRAGE, ICAM-1, IL-8 and Protein C) that were previously associated with PGD when measured at the postoperative time point. We used multivariable logistic regression to adjust for potential confounders. Of 714 subjects, 130 (18%) developed PGD. Median CC-16 levels were elevated in subjects with PGD (10.1 vs. 6.0, p<0.001). CC-16 was associated with PGD in nonidiopathic pulmonary fibrosis (non-IPF) subjects (OR for highest quartile of CC-16: 2.87, 95% CI: 1.37, 6.00, p=0.005) but not in subjects with IPF (OR 1.38, 95% CI: 0.43, 4.45, p=0.59). After adjustment, preoperative CC-16 levels remained associated with PGD (OR: 3.03, 95% CI: 1.26, 7.30, p=0.013) in non-IPF subjects. Our study suggests the importance of preexisting airway epithelial injury in PGD. Markers of airway epithelial injury may be helpful in pretransplant risk stratification in specific recipients.
Primary Graft Dysfunction Grade 3 following Pediatric Lung Transplantation is Associated with Chronic Lung Allograft Dysfunction
(Elsevier, 2023) Wong, Wai; Johnson, Brandy; Cheng, Pi Chun; Josephson, Maureen B.; Maeda, Katsuhide; Berg, Robert A.; Kawut, Steven M.; Harhay, Michael O.; Goldfarb, Samuel B.; Yehya, Nadir; Himebauch, Adam S.; Pediatrics, School of Medicine
Background: Severe primary graft dysfunction (PGD) is associated with the development of bronchiolitis obliterans syndrome (BOS), the most common form of chronic lung allograft dysfunction (CLAD), in adults. However, PGD associations with long-term outcomes following pediatric lung transplantation are unknown. We hypothesized that PGD grade 3 (PGD 3) at 48- or 72-hours would be associated with shorter CLAD-free survival following pediatric lung transplantation. Methods: This was a single center retrospective cohort study of patients ≤ 21 years of age who underwent bilateral lung transplantation between 2005 and 2019 with ≥ 1 year of follow-up. PGD and CLAD were defined by published criteria. We evaluated the association of PGD 3 at 48- or 72-hours with CLAD-free survival by using time-to-event analyses. Results: Fifty-one patients were included (median age 12.7 years; 51% female). The most common transplant indications were cystic fibrosis (29%) and pulmonary hypertension (20%). Seventeen patients (33%) had PGD 3 at either 48- or 72-hours. In unadjusted analysis, PGD 3 was associated with an increased risk of CLAD or mortality (HR 2.10, 95% CI 1.01-4.37, p=0.047). This association remained when adjusting individually for multiple potential confounders. There was evidence of effect modification by sex (interaction p = 0.055) with the association of PGD 3 and shorter CLAD-free survival driven predominantly by males (HR 4.73, 95% CI 1.44-15.6) rather than females (HR 1.23, 95% CI 0.47-3.20). Conclusions: PGD 3 at 48- or 72-hours following pediatric lung transplantation was associated with shorter CLAD-free survival. Sex may be a modifier of this association.
Quantitative Evidence for Revising the Definition of Primary Graft Dysfunction after Lung Transplant
(American Thoracic Society, 2018-01-15) Cantu, Edward; Diamond, Joshua M.; Suzuki, Yoshikazu; Lasky, Jared; Schaufler, Christian; Lim, Brian; Shah, Rupal; Porteous, Mary; Lederer, David J.; Kawut, Steven M.; Palmer, Scott M.; Snyder, Laurie D.; Hartwig, Matthew G.; Lama, Vibha N.; Bhorade, Sangeeta; Bermudez, Christian; Crespo, Maria; McDyer, John; Wille, Keith; Orens, Jonathan; Shah, Pali D.; Weinacker, Ann; Weill, David; Wilkes, David; Roe, David; Hage, Chadi; Ware, Lorraine B.; Bellamy, Scarlett L.; Christie, Jason D.; Medicine, School of Medicine
RATIONALE: Primary graft dysfunction (PGD) is a form of acute lung injury that occurs after lung transplantation. The definition of PGD was standardized in 2005. Since that time, clinical practice has evolved, and this definition is increasingly used as a primary endpoint for clinical trials; therefore, validation is warranted. OBJECTIVES: We sought to determine whether refinements to the 2005 consensus definition could further improve construct validity. METHODS: Data from the Lung Transplant Outcomes Group multicenter cohort were used to compare variations on the PGD definition, including alternate oxygenation thresholds, inclusion of additional severity groups, and effects of procedure type and mechanical ventilation. Convergent and divergent validity were compared for mortality prediction and concurrent lung injury biomarker discrimination. MEASUREMENTS AND MAIN RESULTS: A total of 1,179 subjects from 10 centers were enrolled from 2007 to 2012. Median length of follow-up was 4 years (interquartile range = 2.4-5.9). No mortality differences were noted between no PGD (grade 0) and mild PGD (grade 1). Significantly better mortality discrimination was evident for all definitions using later time points (48, 72, or 48-72 hours; P < 0.001). Biomarker divergent discrimination was superior when collapsing grades 0 and 1. Additional severity grades, use of mechanical ventilation, and transplant procedure type had minimal or no effect on mortality or biomarker discrimination. CONCLUSIONS: The PGD consensus definition can be simplified by combining lower PGD grades. Construct validity of grading was present regardless of transplant procedure type or use of mechanical ventilation. Additional severity categories had minimal impact on mortality or biomarker discrimination.
The relationship between plasma lipid peroxidation products and primary graft dysfunction after lung transplantation is modified by donor smoking and reperfusion hyperoxia
(Elsevier, 2016-04) Diamond, Joshua M.; Porteous, Mary K.; Roberts, L. Jackson; Wickersham, Nancy; Rushefski, Melanie; Kawut, Steven M.; Shah, Rupal J.; Cantu, Edward; Lederer, David J.; Chatterjee, Shampa; Lama, Vibha N.; Bhorade, Sangeeta; Crespo, Maria; McDyer, John; Wille, Keith; Orens, Jonathan; Weinacker, Ann; Arcasoy, Selim; Shah, Pali D.; Wilkes, David S.; Hage, Chadi; Palmer, Scott M.; Snyder, Laurie; Calfee, Carolyn S.; Ware, Lorraine B.; Christie, Jason D.; Medicine, School of Medicine
BACKGROUND: Donor smoking history and higher fraction of inspired oxygen (FIO2) at reperfusion are associated with primary graft dysfunction (PGD) after lung transplantation. We hypothesized that oxidative injury biomarkers would be elevated in PGD, with higher levels associated with donor exposure to cigarette smoke and recipient hyperoxia at reperfusion. METHODS: We performed a nested case-control study of 72 lung transplant recipients from the Lung Transplant Outcomes Group cohort. Using mass spectroscopy, F2-isoprostanes and isofurans were measured in plasma collected after transplantation. Cases were defined in 2 ways: grade 3 PGD present at day 2 or day 3 after reperfusion (severe PGD) or any grade 3 PGD (any PGD). RESULTS: There were 31 severe PGD cases with 41 controls and 35 any PGD cases with 37 controls. Plasma F2-isoprostane levels were higher in severe PGD cases compared with controls (28.6 pg/ml vs 19.8 pg/ml, p = 0.03). Plasma F2-isoprostane levels were higher in severe PGD cases compared with controls (29.6 pg/ml vs 19.0 pg/ml, p = 0.03) among patients reperfused with FIO2 >40%. Among recipients of lungs from donors with smoke exposure, plasma F2-isoprostane (38.2 pg/ml vs 22.5 pg/ml, p = 0.046) and isofuran (66.9 pg/ml vs 34.6 pg/ml, p = 0.046) levels were higher in severe PGD compared with control subjects. CONCLUSIONS: Plasma levels of lipid peroxidation products are higher in patients with severe PGD, in recipients of lungs from donors with smoke exposure, and in recipients exposed to higher Fio2 at reperfusion. Oxidative injury is an important mechanism of PGD and may be magnified by donor exposure to cigarette smoke and hyperoxia at reperfusion.
Risk of Primary Graft Dysfunction Following Lung Transplantation in Selected Adults with Connective Tissue Disease-associated Interstitial Lung Disease
(Elsevier, 2021) Natalini, Jake G.; Diamond, Joshua M.; Porteous, Mary K.; Lederer, David J.; Wille, Keith M.; Weinacker, Ann B.; Orens, Jonathan B.; Shah, Pali D.; Lama, Vibha N.; McDyer, John F.; Snyder, Laurie D.; Hage, Chadi A.; Singer, Jonathan P.; Ware, Lorraine B.; Cantu, Edward; Oyster, Michelle; Kalman, Laurel; Christie, Jason D.; Kawut, Steven M.; Bernstein, Elana J.; Medicine, School of Medicine
Background: Previous studies have reported similarities in long-term outcomes following lung transplantation for connective tissue disease-associated interstitial lung disease (CTD-ILD) and idiopathic pulmonary fibrosis (IPF). However, it is unknown whether CTD-ILD patients are at increased risk of primary graft dysfunction (PGD), delays in extubation, or longer index hospitalizations following transplant compared to IPF patients. Methods: We performed a multicenter retrospective cohort study of CTD-ILD and IPF patients enrolled in the Lung Transplant Outcomes Group registry who underwent lung transplantation between 2012 and 2018. We utilized mixed effects logistic regression and stratified Cox proportional hazards regression to determine whether CTD-ILD was independently associated with increased risk for grade 3 PGD or delays in post-transplant extubation and hospital discharge compared to IPF. Results: A total of 32.7% (33/101) of patients with CTD-ILD and 28.9% (145/501) of patients with IPF developed grade 3 PGD 48-72 hours after transplant. There were no significant differences in odds of grade 3 PGD among patients with CTD-ILD compared to those with IPF (adjusted OR 1.12, 95% CI 0.64-1.97, p = 0.69), nor was CTD-ILD independently associated with a longer post-transplant time to extubation (adjusted HR for first extubation 0.87, 95% CI 0.66-1.13, p = 0.30). However, CTD-ILD was independently associated with a longer post-transplant hospital length of stay (median 23 days [IQR 14-35 days] vs17 days [IQR 12-28 days], adjusted HR for hospital discharge 0.68, 95% CI 0.51-0.90, p = 0.008). Conclusion: Patients with CTD-ILD experienced significantly longer postoperative hospitalizations compared to IPF patients without an increased risk of grade 3 PGD.

Browsing by Author "Kawut, Steven M."

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