A nuclear cardiac stress test shows how blood flows through the heart and heart muscle, states Mayo Clinic. A radioactive dye is injected into the bloodstream, and X-ray images of the heart are taken while the patient is at rest and when the heart is under stress.
Nuclear cardiac stress tests are used to observe the size and shape of a heart, diagnose coronary artery disease and establish treatment plans for heart disorders, explains Mayo Clinic. Complications of a nuclear cardiac stress test are rare and include chest pain, a flushing sensation, an allergic reaction to the radioactive dye and an abnormal heart rhythm. Heart attack is another possible complication, though this occurs extremely rarely.
Any inhalers prescribed to the patient should be brought to a nuclear cardiac stress test, and comfortable shoes and clothes should be worn, recommends Mayo Clinic. Doctors may request that the patient abstain from eating, drinking and smoking two hours before the test. Medication and caffeine may be prohibited before testing to help ensure accuracy.
Nuclear cardiac stress tests take from two to five hours, explains Mayo Clinic. An IV is inserted into the patient's arm or hand to insert radioactive dye into the bloodstream. Electrodes are placed on the patient's chest, arms and legs, and a blood pressure cuff is placed on the patient's arm. The patient then exercises to increase blood flow to the heart, or medication is administered through the IV to simulate exertion. Light spots on the X-ray images represent inadequate blood flow to areas of the heart.