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Lead

Thallium (Tl), chemical element, metal of main Group 13 (IIIa, or boron group) of the periodic table, poisonous and of limited commercial value. Like lead, thallium is a soft, low-melting element of low tensile strength.

There is more thallium-203 in nature. Atoms of both isotopes have 81 protons. Thallium-205 atoms have fewer neutrons. The most common atom of thallium has a mass of 204.38 amu.

Uses of thallium Thallium is used in photoresistors, infrared optical equipment, low melting glasses and several other applications. Thallium sulfate has been used as a rodent and ant killer because it’s odorless and tasteless. However, the use of the product has been prohibited since 1972 in the United States.

Tl-201 emits emitting mainly X-rays of energy 67–82 keV (88% abundance) and gamma photons of 135 and 167 keV (12% abundance). X or gamma rays could not be visible.

Thallium can affect your nervous system, lung, heart, liver, and kidney if large amounts are eaten or drunk for short periods of time. Temporary hair loss, vomiting, and diarrhea can also occur and death may result after exposure to large amounts of thallium for short periods.

Thallium poisoning is poisoning due to thallium and its compounds which are often highly toxic. Contact with skin is dangerous, and adequate ventilation should be provided when melting this metal. Many thallium(I) compounds are highly soluble in water and are readily absorbed through the skin.

A thallium (or cardiolite) scan uses a radioactive tracer to see how much blood is reaching different parts of your heart. These tests are the more common forms of tests called nuclear medicine scans. You may also hear them called: thallium myocardial imaging.

It is also known at the thallium stress test, a myocardial perfusion scan, or a radionuclide test. The test can be done while the patient is resting or doing exercise. The radioactive substance that is injected into the patient is called a radionuclide. The test takes about 3 to 4 hours.

Thallium scan: A method of examining the heart to obtain information about the blood supply to the heart muscle. In the scan, special cameras take a series of pictures of the heart. Radioactive sestamibi is injected into the bloodstream and serves as a tracer.

A thallium stress test is a nuclear medicine study that shows your physician how well blood flows through your heart muscle while you’re exercising or at rest. This exam also allows your physician to visualize whether there has been any damage done to your heart by any problems you may have had previously.

Heart failure signs and symptoms may include:

• Shortness of breath (dyspnea) when you exert yourself or when you lie down.
• Fatigue and weakness.
• Swelling (edema) in your legs, ankles and feet.
• Rapid or irregular heartbeat.
• Reduced ability to exercise.
• Persistent cough or wheezing with white or pink blood-tinged phlegm.

Stress tests can detect when arteries have 70% or more blockage. This severe narrowing is what causes the severe chest pain called angina. But normal results from a stress test do not rule out the possibility of a future heart attack. This is because a plaque can still rupture, form clots and block an artery.

Do clogged arteries cause any symptoms?

• Chest pain.
• Shortness of breath.
• Heart palpitations.
• Weakness or dizziness.
• Nausea.
• Sweating.

Your doctor might recommend a stress echocardiogram to check for coronary artery problems. However, an echocardiogram can’t provide information about any blockages in the heart’s arteries.

By clinical guidelines, an artery should be clogged at least 70 percent before a stent should be placed, Resar said. “A 50 percent blockage doesn’t need to be stented,” he said.

While the placement of stents in newly reopened coronary arteries has been shown to reduce the need for repeat angioplasty procedures, researchers from the Duke Clinical Research Institute have found that stents have no impact on mortality over the long term.

A moderate amount of heart blockage is typically that in the 40-70% range, as seen in the diagram above where there is a 50% blockage at the beginning of the right coronary artery. Usually, heart blockage in the moderate range does not cause significant limitation to blood flow and so does not cause symptoms.

A drug-eluting stent is coated with time-release medicine. That medication is gradually released into your blood vessel to prevent it from becoming blocked again.

Symptoms will usually tell you if there’s a problem. If that happens, you usually have symptoms—like chest pain, fatigue, or shortness of breath. If you do have symptoms, a stress test can help your doctor see what’s going on. It can show if a blockage has returned or if there’s a new blockage.

Don’t lift heavy objects. Avoid strenuous exercise. Avoid sexual activity for a week. Wait at least a week before swimming or bathing.

As recommended in the National Disease Management Guidelines (6), patients with coronary heart disease and those who have undergone stent implantation should be followed up regularly (every three to six months) by their primary care physicians, independently of any additional visits that may be necessitated by …

A sizeable proportion of patients who undergo successful coronary artery stent implantation experiences chest pain immediately after the procedure and/or in the following months in the absence of in-stent restenosis.

Recovery from angioplasty and stenting is typically brief. Discharge from the hospital is usually 12 to 24 hours after the catheter is removed. Many patients are able to return to work within a few days to a week after a procedure.

Having a stent placed is a minimally invasive procedure, meaning it is not a major surgery. Stents for coronary arteries and carotid arteries are placed in similar ways. A stent graft is placed to treat an aneurysm in a procedure called aortic aneurysm repair.