Craig J. Hartley, Ph.D.
chartley@bcm.edu
Professor, Department of Medicine, Cardiovascular Sciences
Research Interests
Ultrasonic Instrumentation for Cardiovascular Research
Since 1973 Dr. Hartley's laboratory has been developing and applying ultrasonic instrumentation and implantable sensors for measuring blood flow and cardiac function in animal models of cardiovascular disease. Many of the sensors have also been used in patients to measure coronary blood flow and myocardial function before and after coronary artery bypass surgery and balloon angioplasty. Smaller versions of these sensors are now being applied to mice. Collaborative projects are active with many investigators both in Medicine and across departmental and institutional lines. This laboratory offers a unique combination of capabilities and opportunities to apply engineering principles to the study of the cardiovascular system in animals and in man.
Current Active Projects
Transgenic mice are used as models of human cardiovascular disease, but it has been difficult to evaluate cardiovascular function in small animals. We are designing and applying non-invasive techniques to measure cardiac velocities, regional blood flow, cardiac dimensions and volume, arterial pulse-wave velocity and diameter pulsations, and blood pressure in mice using ultrasound, ECG, and other modalities. We have been using these methods in mice to characterize several models of cardiovascular dysfunction including: LV hypertrophy, coronary occlusion and reperfusion, hyperthyroidism, senescence, diet restriction, atherosclerosis, and several other genetic models. The goal is to validate the measurement techniques and analytical methods and to establish the mouse as a viable model for studying human cardiovascular pathophysiology. As part of this goal we are characterizing the mechanical properties of the mouse cardiovascular system in health and disease.
Recently we have been able to measure left main coronary blood flow velocity and coronary flow reserve (CFR) noninvasively and serially in anesthetized mice using inhaled isoflurane as a coronary vasodilator. The coronary velocity waveforms, the magnitude of CFR, and the responses to atherosclerotic, ischemic, and hypertrophic cardiac disease models are similar to those in man. The ability to assess CFR in mice quickly and non-invasively will enable us to study the physiological effects of various diseases on the coronary circulation in depth.