The Whole Heart
Seminar Room 1, Newton Institute
The heart, great vessels and passing blood function as a dynamically interconnected whole. As a counterpart to more analytical approaches, this presentation includes images chosen to encourage an integrated and contextualized view of the heart. It begins with photographs of the Earth, where it has been deduced from fossil evidence that our vertebrate ancestors have been evolving for some 500 million years. It includes magnetic resonance cine images, photographs of endovascular casts, and illustrations of human, vertebrate and invertebrate hearts, and concludes with a simulation of flow through a healthy heart during exercise, prepared in collaboration with Michael Markl and colleagues in Freiburg. The images used for this were from a resting, 3-dimensional, time-resolved, 3-component magnetic resonance flow velocity acquisition in a healthy volunteer. To simulate a moderate (walking) state of exercise, the second half of diastole was removed and the remaining frames played back at 100 cycles/minute. The movie helps to make apparent the changes of momentum, and associated cyclic exchanges of force and counter-force, that must accompany the movements of blood through the curvatures of the heart and aorta on exercise.