Over the past three decades, increasing attention has focused on the hypertensive diseases. During this period, antihypertensive therapy was introduced, and its safety and efficacy were demonstrated. Accompanying these advances in therapy was a tremendous expansion in our understanding of the underlying pathophysiologic mechanisms of hypertensive diseases. With respect to the role of the cardiovascular system in hypertension, investigators in the 1960s and '70s called attention to the heterogeneity of the systemic and regional hemodynamic alterations associated with the hypertensive diseases.¹ By the late 1970s and '80s, more interest was being directed to the role of the heart in hypertension. . . .