Spectral Doppler Processing and Quantification in the Context of Progressive Aortic Stenosis; The Struggle to Reduce Cardiovascular Disease in the United States through Dietary Interventions

How can the incidence of cardiovascular disease be diminished? Due both to biological mechanisms and to social determinants of health, cardiovascular disease (CVD) remains the leading cause of death worldwide. At the intersection between the greatest risk factors and novel biomedical engineering approaches lie opportunities for better CVD prevention and treatment.
Current technologies are unable to quantify low-amplitude, high-velocity (LAHV) signals from continuous wave (CW) Doppler echocardiography, despite its potential as a marker of rapidly progressing aortic stenosis (AS). AS is a prevalent and costly heart valve disease in aging populations, lacking pharmacologic treatments and often requiring surgical replacement. High shear stress on the aortic valve may accelerate disease progression through activation of Von Willebrand Factor (VWF). LAHV signal, often described as “fuzz” on CW Doppler, may serve as a marker of such shear forces. To quantify these signals, a MATLAB program was developed that denoises the images, plots velocity-intensity histograms, and calculates the area under the curve (AUC) for LAHV regions beyond the main Doppler jet. Preliminary results showed that AUC values correlated strongly with expert visual grading and blood-based shear markers (p<0.001). This program offers a novel, noninvasive method to quantify LAHV signals without accessing raw Doppler data. Future validation studies may position this tool as a critical step toward stratifying patients for emerging therapies.
Diet is a major component of CVD risk. In diverse ways, policymakers, media, the food and pharmaceuticals industries, healthcare systems, insurers and employers are promoting dietary means of reducing CVD morbidity and mortality. While diet is often framed as a matter of personal responsibility, the public understanding and adoption of heart-healthy dietary practices are shaped by larger institutional forces. Institutional forces interact with public policy, economics and marketing to create an environment in which dietary recommendations are often contradictory, commercialized, or confusing to the public. Public health policy, medical education, corporate influence, and consumer media shape how dietary guidance is produced, communicated, and received. Better CVD prevention will require policy reforms that improve transparency in research and regulation, and that empower individuals by giving them clear, valid and context-sensitive nutritional guidance.

School of Engineering and Applied Science

Bachelor of Science in Biomedical Engineering

Technical Advisor: Johnathan Lindner, John Hossack

STS Advisor: Peter Norton

Technical Team Members: Sophie Phillips, Lily Thomson