Noninvasive photoacoustic measurement of the composite indicator dilution curve for cardiac output estimation

Abstract

Abstract:Recently, the measurement of indicator dilution curves using a photoacoustic (PA) technology was reported, which showed promising results on the noninvasive estimation of cardiac output (CO) that is an important hemodynamic parameter useful in various clinical situations. However, in clinical practice, measuring PA indicator dilution curves from an arterial blood vessel requires an ultrasound transducer array capable of focusing on the targeted artery. This causes several challenges on the clinical translation of the PA indicator dilution method, such as high sensor cost and complexity. In this paper, we theoretically derived that a composite PA indicator dilution curve simultaneously measured from both arterial and venous blood vessels can be used to estimate CO correctly. The ex-vivo and in-vivo experimental results with a flat ultrasound transducer verified the developed theory. We believe this new concept would overcome the main challenges on the clinical translation of the noninvasive PA indicator dilution technology.

Advanced Ultrasound and Photoacoustic Imaging in Cardiology

“…Another study by Kang [ 142 , 143 ] introduced a new concept of a non-invasive PA-based indicator dilution measurement, and developed an advanced method to measure the cardiac output, which is an important hemodynamic parameter for assessment of cardiac function, and is especially helpful for monitoring and optimizing the fluid status in high-risk surgical and critically ill patients.…”

Breakthroughs in modern cancer therapy and elusive cardiotoxicity: Critical research‐practice gaps, challenges, and insights

“…273,283 Various exogenous probes with high contrast have also been extensively developed, including inorganic and organic dyes, 274 magneto-optical and photochromic probes, 283 nanoparticles, 282,287 and genetically encoded probes, 281 to achieve improved resolution and sensitivity while providing multi-parametric photoacoustic imaging. 283 This imaging modality has proven its clinical and preclinical value in functional, structural, and molecular aspects of diseases and has been used for physiologically and pathologically imaging various organs and tissues, including breast cancer, [288][289][290][291][292] neural tissues, 277,287,[293][294][295] fingers, 296 sentinel lymph nodes, 277,292,297 the cardiovascular system, [298][299][300][301][302] the prostate, 303,304 skin, 305 cancer therapy, 273,274,306 muscle oxygenation, 307 metabolic status, 274,283 eyes, 308,309 plaque pathophysiology, 310 tumor microenvironment (pH, enzymes, radical oxidation species (ROS), and metal ions, among others), 274 and biomaterial-tissue interactions to assess the functions of the engineered tissue/organ constructs. <...>…”