Common variants of the G protein-coupled receptor type 4 are associated with human essential hypertension and predict the blood pressure response to angiotensin receptor blockade.

Non-synonymous GRK4 variants, R65L, A142V and A486V, are associated with essential hypertension in diverse populations. This study replicated the association of GRK4 variants, including GRK4(142V), with human essential hypertension in a Japanese population (n=588; hypertensive, n=486 normotensive controls) and determined whether the presence of GRK4 variants predicted the blood pressure (BP) response to angiotensin receptor blockers (ARBs) in patients with essential hypertension. We analyzed 829 patients and compared the response to ARBs between individuals with no GRK4 variants (n=136) and those with variants at one or any of the three loci (n=693). Carriers of hGRK4(142V) had a greater decrease in systolic BP in response to ARBs than non-carrier hypertensive patients. By contrast, those with variants only at GRK4(486V) were less likely to achieve the BP goal in response to an ARB than those with no variants. These studies showed for the first time the association between GRK4(142V) and a larger decrease in BP with ARBs in hypertensive patients.

Colour Doppler velocity imaging of the myocardium.

A technique has been developed for producing images of the velocity of tissue motion within the myocardium. It has been demonstrated that Colour Flow Doppler imagers can be operated to depict the velocities within the myocardium rather than moving blood in the cardiac chambers. The technique exhibits the normal advantages of diagnostic ultrasound, i.e., real-time imaging with relatively inexpensive equipment and no hazard to the patient. Further work requires to be done to determine the optimum signal processing algorithms for moving tissue echoes and to ascertain whether the technique is of value in clinical applications.