Hypertension Blog

Echocardiography uses sound waves to evaluate the heart’s structure and function. In this test, a transducer is positioned on various areas of the chest. The transducer emits sound waves, which make contact with the heart and are then recorded on a monitor as moving images of it. Using this test, a physician can observe a patient’s systolic and diastolic function, calculate the sizes of the cardiac chambers, measure left ventricular wall thickness, and measure valve areas.An echocardiogram can accurately detect ischemia or left ventricular hypertrophy resulting from hypertension. On an echocardiogram, ischemic changes appear as wall-motion abnormalities. However, standard echocardiography may not detect ischemia of the left ventricle.

To detect such ischemia, a physician may order stress echocardiography. This test is performed immediately after the patient exercises. Patients who can’t exercise are tested by pharmacologic stress echocardiography. Dobutamine, an inotropic agent, is administered I.V. as the patient lies in bed. The examiner gradually increases the dose until the patient’s heart rate mimics an exercise heart rate. Then, echocardiography is performed to evaluate the heart wall for motion abnormalities.

Echocardiography also helps in evaluating a patient’s response to hypertensive therapy. For instance, calcium channel blockers can decrease left ventricular hypertrophy and the occurrence of arrhythmias; follow-up echocardiographic testing can verify this response to therapy.

Stress or pharmacologic stress echocardiograms are usually performed when cardiac isoenzymes have returned to normal 7 to 10 days after surgery or an acute ML And some patients then have these tests performed several months later so that the physician can evaluate therapy and progress.

Nursing Considerations

When preparing a patient for an echocardiogram, advise him that he may feel some discomfort during the test because the technician must place the transducer firmly between the ribs to enhance sound-wave transmission and diminish interference. Also, advise your patient that he’ll have to lie quietly for 30 to 45 minutes, depending on the technical quality of sound-wave transmission and the cardiac images.