Figure 2.03. Some factors contributing to afterload. What are shown here are the effects of increased vascular resistance and vascular compliance. Another major factor not shown is heart dimension, ie. a dilated heart sustains greater afterload at the same arterial or ventricular pressure than a smaller heart (a larger heart has larger radii of curvature and through the Law of Laplace is at greater mechanical disadvantage relative to internal pressure than a smaller heart).