Pulmonary hypertension is a critical determinant of morbidity and mortality in various pediatric diseases. Despite advances in therapies, long-term outcomes in many settings remain poor. Although reasons for this are multi-factorial, one critical component is the relative lack of disease-defining knowledge regarding the functional impact of the disease on the right heart and coupled pulmonary vasculature. In fact, clinically, pulmonary arterial hypertension continues to be evaluated predominantly as a distal vascular phenomenon, and only limited recognition is given to the fact that the pulmonary arterial system (PA) is intimately coupled with right ventricular function in health and disease. Functionally speaking, RV-PA coupling is driven by the principles of hydrodynamic and mechanical energy transfer and is thus not markedly dependent on the biological heterogeneity of the pediatric PH population. Over the last 7 years, our group using a reverse "bedside-to-bench" approach have developed novel markers of RV afterload using vascular input impedance principles, and have shown on studies of over 250 pediatric subjects with pulmonary hypertension that PVR does not represent the sole metric of RV afterload, that PA stiffness increases dramatically in pediatric pulmonary hypertension patients and consequently loads the RV to a proportionally greater level, and that inclusion of impedance and PA stiffness measures improves prediction of 1-year outcomes. These clinical studies generated a series of mechanistic studies to understand how the upstream pulmonary vessels stiffen, which have led to novel and interesting hypotheses regarding the role of extracellular matrix proteins in upstream vascular remodeling, mechanisms of healthy versus maladaptive remodeling, and differences in the developing versus the fully developed RV-PA system. These are currently being tested by our group and others through parallel efforts. This K24 project proposes a unique combination of research studies and training efforts to advance clinical evaluation of PH while training clinical research fellows with both sold fundamental understanding of underlying physics and hemodynamics and accurate application of such principles to novel clinical diagnostics.
Pulmonary hypertension (high blood pressure in the lungs) is a fatal disease in children. Although many treatments are being developed, methods to evaluate the disease clinically are still incomplete. In this grant, we will develop new non-invasive methods to comprehensively characterize this disease in children. We will also train the next generation of clinical investigators to better understand and diagnose this complex disease.
|Kheyfets, Vitaly O; Dunning, Jamie; Truong, Uyen et al. (2016) A Zero-Dimensional Model and Protocol for Simulating Patient-Specific Pulmonary Hemodynamics From Limited Clinical Data. J Biomech Eng 138:|
|Zimkowski, Michael M; Rentschler, Mark E; Schoen, Jonathan A et al. (2014) Biocompatibility and tissue integration of a novel shape memory surgical mesh for ventral hernia: in vivo animal studies. J Biomed Mater Res B Appl Biomater 102:1093-100|
|Yunker, Bryan E; Dodd, Gerald D; Chen, S James et al. (2014) The design and fabrication of two portal vein flow phantoms by different methods. Med Phys 41:023701|
|Scott, Devon; Tan, Yan; Shandas, Robin et al. (2013) High pulsatility flow stimulates smooth muscle cell hypertrophy and contractile protein expression. Am J Physiol Lung Cell Mol Physiol 304:L70-81|
|Brown, R Dale; Ambler, S Kelly; Li, Min et al. (2013) MAP kinase kinase kinase-2 (MEKK2) regulates hypertrophic remodeling of the right ventricle in hypoxia-induced pulmonary hypertension. Am J Physiol Heart Circ Physiol 304:H269-81|
|Su, Zhenbi; Tan, Wei; Shandas, Robin et al. (2013) Influence of distal resistance and proximal stiffness on hemodynamics and RV afterload in progression and treatments of pulmonary hypertension: a computational study with validation using animal models. Comput Math Methods Med 2013:618326|
|Yunker, Bryan E; Cordes, Dietmar; Scherzinger, Ann L et al. (2013) An investigation of industrial molding compounds for use in 3D ultrasound, MRI, and CT imaging phantoms. Med Phys 40:052905|
|Colvin, Kelley L; Cripe, Patrick J; Ivy, D Dunbar et al. (2013) Bronchus-associated lymphoid tissue in pulmonary hypertension produces pathologic autoantibodies. Am J Respir Crit Care Med 188:1126-36|
|Su, Zhenbi; Hunter, Kendall S; Shandas, Robin (2012) Impact of pulmonary vascular stiffness and vasodilator treatment in pediatric pulmonary hypertension: 21 patient-specific fluid-structure interaction studies. Comput Methods Programs Biomed 108:617-28|
|Lammers, Steven; Scott, Devon; Hunter, Kendall et al. (2012) Mechanics and Function of the Pulmonary Vasculature: Implications for Pulmonary Vascular Disease and Right Ventricular Function. Compr Physiol 2:295-319|
Showing the most recent 10 out of 27 publications