Hypertension has adverse effects on the heart and the blood vessels and is a major problem in developed countries. In the United States alone, there are over fifty million afflicted people or one in every four adults. Hypertension is defined as a systolic blood pressure greater than 140 mmHg and/or a diastolic blood pressure greater than 90 mmHg. Approximately twenty-five to fifty percent of individuals have hypertensive heart disease that results in left ventricular hypertrophy. Hypertension and left ventricular hypertrophy are the two most important risk factors for the development of congestive heart failure, a problem that affects over five million Americans. Congestive heart failure is a clinical condition in which the pumping action of the ventricle of the heart is inadequate. Despite the large amount of epidemiological data linking hypertensive left ventricular hypertrophy to adverse cardiovascular results, little is known about the mechanisms mediating the transition from hypertrophy to heart made.

The purpose of the study was to determine if patients with hypertension and patients with congestive heart failure have diastolic dysfunction by a non-invasive test, echocardiography. Pulsed Doppler echocardiography can be used for evaluation of blood flow velocities at the mitral valve orifice from a transducer at the apex of the heart. These measurements provide an accurate means of determining the rate of blood flow from the left atrium to the left ventricle. Tissue Doppler imaging was used to assess diastolic function. TDI measures the velocity of tissue rather than blood. By combining these measurements, an accurate determination of both the blood flow through the heart and the velocity of the walls of the heart can be analyzed.

Measurements were made of pulsed Doppler and tissue Doppler diastolic velocities in a total of sixty patients including a normal control (n=20), hypertensive (n=20), and a heart failure group (n=20). The data revealed that mitral diastolic inflow velocities are higher in the congestive heart failure group as compared to both the normal group and the hypertensive group. Myocardial tissue velocities are lower in congestive heart failure subjects than normal controls and hypertensive subjects.

In conclusion, both pulsed Doppler echocardiography and tissue Doppler Imaging can be used to detect abnormal diastolic function in congestive heart failure.

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