Browsing by Subject "Right ventricle"

Now showing 1 - 4 of 4
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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.
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    Estrogen receptor-α prevents right ventricular diastolic dysfunction and fibrosis in female rats
    (American Physiological Society, 2020-12) Cheng, Tik-Chee; Philip, Jennifer L.; Tabima, Diana M.; Kumari, Santosh; Yakubov, Bakhtiyor; Frump, Andrea L.; Hacker, Timothy A.; Bellofiore, Alessandro; Li, Rongbo; Sun, Xin; Goss, Kara N.; Lahm, Tim; Chesler, Naomi C.; Medicine, School of Medicine
    Although women are more susceptible to pulmonary arterial hypertension (PAH) than men, their right ventricular (RV) function is better preserved. Estrogen receptor-α (ERα) has been identified as a likely mediator for estrogen protection in the RV. However, the role of ERα in preserving RV function and remodeling during pressure overload remains poorly understood. We hypothesized that loss of functional ERα removes female protection from adverse remodeling and is permissive for the development of a maladapted RV phenotype. Male and female rats with a loss-of-function mutation in ERα (ERαMut) and wild-type (WT) littermates underwent RV pressure overload by pulmonary artery banding (PAB). At 10 wk post-PAB, WT and ERαMut demonstrated RV hypertrophy. Analysis of RV pressure waveforms demonstrated RV-pulmonary vascular uncoupling and diastolic dysfunction in female, but not male, ERαMut PAB rats. Similarly, female, but not male, ERαMut exhibited increased RV fibrosis, comprised primarily of thick collagen fibers. There was an increased protein expression ratio of TIMP metallopeptidase inhibitor 1 (Timp1) to matrix metalloproteinase 9 (Mmp9) in female ERαMut compared with WT PAB rats, suggesting less collagen degradation. RNA-sequencing in female WT and ERαMut RV revealed kallikrein-related peptidase 10 (Klk10) and Jun Proto-Oncogene (Jun) as possible mediators of female RV protection during PAB. In summary, ERα in females is protective against RV-pulmonary vascular uncoupling, diastolic dysfunction, and fibrosis in response to pressure overload. ERα appears to be dispensable for RV adaptation in males. ERα may be a mediator of superior RV adaptation in female patients with PAH. NEW & NOTEWORTHY Using a novel loss-of-function mutation in estrogen receptor-α (ERα), we demonstrate that female, but not male, ERα mutant rats display right ventricular (RV)-vascular uncoupling, diastolic dysfunction, and fibrosis following pressure overload, indicating a sex-dependent role of ERα in protecting against adverse RV remodeling. TIMP metallopeptidase inhibitor 1 (Timp1), matrix metalloproteinase 9 (Mmp9), kallikrein-related peptidase 10 (Klk10), and Jun Proto-Oncogene (Jun) were identified as potential mediators in ERα-regulated pathways in RV pressure overload.
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    Isolated Right Ventricular Myocardial Infarction Presenting With Anterior ST-Segment Elevation
    (Elsevier, 2022-05-04) Mallory, Ryan; Kreutz, Rolf P.; Medicine, School of Medicine
    Isolated right ventricular myocardial infarctions (MIs) are rare, especially those presenting with anterior ST-segment elevation, which is normally seen in anterior MI. This occurs if the right coronary artery is nondominant. Differentiating between them is important for clinical management. Our case demonstrates a right ventricular MI presenting as an anterior ST-segment elevation myocardial infarction.
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    Right Ventricular Infarction Presenting With Refractory Hypoxia Due to Shunting Across a Patent Foramen Ovale
    (Elsevier, 2021-03-03) Wilson, Stephanie M.; Phookan, Sujoy; Kovacs, Richard J.; Medicine, School of Medicine
    Right ventricular infarction is often associated with significant morbidity and mortality. Here, we report a case of right ventricular infarction associated with persistent hypoxia due to acute right-to-left shunting through a patent foramen ovale.