Ventriculography

Norm of Ventriculography

Normal cardiac ventricular structure; lack of disease process.

 

Usage of Ventriculography

Noninvasive test to detect changes in heart function, assess for cardiac damage, and evaluate heart-wall motion and pumping function. Conditions include atrial septal defect, cardiomyopathy, heart failure, Lyme disease (secondary), mitral stenosis, and superior vena cava obstruction. May be used before coronary angiography to detect those clients with severe coronary artery disease who are at risk for angiographic procedural complications.

 

Description of Ventriculography

Ventriculography is a noninvasive nuclear medicine test that allows for the heart chambers and major blood vessels to be outlined. A small dose of a radioactive isotope is injected in the client's veins. The isotope attaches itself to red blood cells that then pass through the heart. Special scanners or cameras can track the radioactive isotopes as they flow through the heart. The image is often synchronized with an electrocardiogram. Frequently the test is given in two stages: one at rest, one with exercise.

 

Professional Considerations of Ventriculography

Consent form MAY be required.

Risks
Small exposure to radiation from the radioactive isotopes. With exercise testing, potential for cardiac ischemia, myocardial infarction, dysrhythmias, blood pressure changes.
Contraindications
Clients unable to lie motionless for the scan, previous allergy to radioisotope.
Precautions
During pregnancy, risks of cumulative radiation exposure to the fetus from this and other previous or future imaging studies must be weighed against the benefits of the procedure. Although formal limits for client exposure are relative to this risk:benefit comparison, the United States Nuclear Regulatory Commission requires that the cumulative dose equivalent to an embryo/ fetus from occupational exposure not exceed 0.5 rem (5 mSv). Radiation dosage to the fetus is proportional to the distance of the anatomy studied from the abdomen and decreases as pregnancy progresses. For pregnant clients, consult the radiologist/ radiology department to obtain estimated fetal radiation exposure from this procedure.

 

Preparation

  1. Have emergency equipment available.
  2. Obtain baseline ECG.
  3. Review for history of allergic type of responses to radiographic dyes.

 

Procedure

  1. Insert an intravenous access device.
  2. Inject the isotope.
  3. A scanner will be placed over the chest area.
  4. Imaging takes place; depending on the type of test, the client may have a resting image, a resting and then an exercise image, or an exercise and then a resting image.

 

Postprocedure Care

  1. Assess for any chest pain or discomfort.
  2. For scans that involved exercise, monitor the client until vital signs return to baseline values.
  3. Ensure proper disposal of any radioactive waste.

 

Client and Family Teaching

  1. Do not ingest caffeine or any stimulants for 3–6 hours before the test.
  2. Because this test may take some time, bring items to occupy yourself while waiting.
  3. Wear comfortable clothing.
  4. In women who are breast-feeding, formula should be substituted for breast milk for 1 or more days after the procedure.

 

Factors That Affect Results

  1. Client's ability to remain motionless for the scan.
  2. Drugs that alter cardiac contractility.
  3. Recent MI (within 24 hours).
  4. Recent previous exposure to radioactive tracers may interfere with the quality of the scan.
  5. The decrement of the R-wave amplitude changes can indicate clients with three-vessel disease at risk of angiographic complications.
  6. Standard volumes of contrast material are often associated with ventricular ectopy, which makes the readings uninterpretable. Reducing the volume of contrast material from 15 mL/second for 3 seconds to 15 mL/second for 1 second has been shown to reduce ectopy without affecting results.

 

Other Data

  1. Abnormal findings in the scan may indicate the need for more extensive studies.
  2. Health care professionals working in a nuclear medicine area must follow federal standards set by the Nuclear Regulatory Commission. These standards include precautions for handling the radioactive material and monitoring potential radiation exposure.