A paradigm for quantifying ventricular contraction.

The left ventricle may be described as a time, volume and flow dependent pressure generator. First, isovolumic pressure is measured at various end-diastolic volumes. Next, pressure is adjusted to account for small changes accompanying ejection, denoted the ejection effect. The resulting analytical function can describe pressure generation and ventricular outflow of the ventricle under a wide range of contractile and vascular conditions. This paradigm is unique in separating isovolumic from ejecting ventricular properties, as well as ventricular from vascular conditions.