Abstract
Increasing interest in identifying the causes of and treatments for heart failure with preserved ejection fraction and cardiac fibrosis has spawned a focus on measures of cardiac diastolic function. The methods, their underlying principals and mechanics, and caveats to their measurement were largely worked out decades ago, but some of this seems a bit forgotten as scientists working in the field now have backgrounds more in molecular and cellular biology. This perspective was spawned by seeing the growing number of studies where diastolic function analysis is a key parameter used to justify a given pre-clinical model or to show the consequences of a particular genetic or pharmacological therapy. The goals are to discuss what comprises and influences diastolic function, how it is measured, what the parameters mean and what their limitations are, and what comprises evidence for pathophysiologically meaningful diastolic dysfunction.