The online site for History Today recently featured a book review by Andrew Robinson for The Prince of Medicine: Galen in the Roman Empire by Susan P. Mattern.
From the review:
The physician Galen of Pergamum was the leading anatomist of antiquity. However his science was based on dissection of animals, since the dissection of humans was virtually taboo in the Roman Empire. He was, therefore, mistaken in many of his views of human anatomy, such as the structure of the heart (though he did disprove Aristotle’s notion that the heart was the seat of reason, noting that gladiators wounded in the heart remained lucid until death). Not until the Renaissance did Andreas Vesalius undertake human dissection in earnest and reveal the true cardiac anatomy. Indeed Vesalius acknowledged his debt to Galen, calling him the ‘prince of medicine’ in the second edition of his De Fabrica Corporis Humani (1555). However neither Galen nor Vesalius grasped the concept of circulation of the blood, pumped by the heart, which was discovered only in the 17th century.