Medical Tests & Procedures Archive

These high-tech devices can save — and change — a person's life.

Implantable cardioverter-defibrillators (ICDs) save many lives. They monitor the heart's rhythm and rate, emitting a low-energy electrical correction when they detect a minor heart rate abnormality. They can also deliver a more significant jolt, likened to a swift kick in the chest, to halt potentially life-threatening rhythm disruptions.

About 10 million people in the United States have essential tremor (ET), a movement disorder that causes uncontrollable shaking of the hands and often the head as well, and sometimes a quavering voice. ET is an action tremor, meaning that the shaking is largely absent when you're at rest but increases when you try to use your hands — for example, to pick up a cup or use a fork. (ET is sometimes mistaken for Parkinson's disease, in which it's the other way around: the tremor is noticeable during rest and stops with activity.)

There's no cure for ET, but clinicians have various ways to control the symptoms, including drugs and surgery. The American Academy of Neurology (AAN) has issued updated treatment guidelines, based on a review of 252 studies published since 2005, when the AAN issued its first evidence-based guidelines for the treatment of ET. Results were published in Neurology (Nov. 8, 2011).

Q. I am 77 years old, and my doctor recommended surgery to replace my aortic valve. He said my choice is between a mechanical valve and a pig valve. Which is the preferred option?

A. Generally, people with mechanical and tissue (pig) valves do comparably well. However, your age and other factors can play a role in selecting one or the other. Tissue valves typically wear out before mechanical valves do, often in 15 years or less.

Q. I have Dupuytren's contracture in both hands. I've had "needle" surgery in one hand, and the fingers straightened. But they seem to want to contract again. What can I do?

A. Dupuytren's contracture is a disorder that develops when the palmar fascia — the tissue between the skin and tendons in the palm — thickens and contracts due to an abnormal buildup of collagen, causing one or more fingers (usually the little and ring fingers) to bend inward. Over time, Dupuytren's can make it difficult or impossible to grasp objects, button buttons, use a computer, and perform many other everyday activities. The treatment you mention sounds like needle aponeurotomy (also called percutaneous needle fasciotomy), in which a needle is used to sever the cords that are causing the fingers to contract. Unfortunately, recurrence following treatment is common.

Q. Ten years ago, I had uterine artery embolization to get rid of uterine fibroids. How long do the plastic particles they inject into the arteries stay in the body? Do they dissolve?

A. Uterine artery embolization (UAE), also called uterine fibroid embolization, is a minimally invasive treatment that shrinks uterine fibroids by cutting off their blood supply. During UAE, an interventional radiologist inserts a catheter into the femoral artery through a small nick in the skin at the groin and guides it into one of the two uterine arteries, which supply blood to the uterus. Contrast dye is injected to help visualize the uterine artery as well as the smaller branching vessels that feed the fibroid. The radiologist then injects tiny synthetic particles, or beads, which concentrate in the smaller vessels, forming a clot that cuts off the fibroid's blood supply. Lacking blood, the fibroid gradually shrinks.

Medical therapy is better for late treatment.

Imagine this scenario: You've finally gone to the hospital because of chest pain you were having yesterday. After an electrocardiogram and blood test, you're told that sometime in the preceding 24 hours a clot in one of your coronary arteries cut off the blood supply to a section of your heart muscle. You had a heart attack!

So should you get an artery-opening angioplasty?

No. In 2006, the Occluded Artery Trial (OAT) determined that performing angioplasty — an invasive and expensive procedure — delivered no tangible benefit to people who'd had a heart attack more than 24 hours earlier and who no longer had symptoms.

Checking your heart's electrical activity with an electrocardiogram (ECG) or exercise stress test makes perfect sense if you or your doctor suspects cardiac trouble. What if you feel fine — no chest pain, shortness of breath or tiredness, or other symptoms of heart disease? Should you have an ECG or exercise stress test to "check under the hood" for undiscovered heart disease? No, says the U.S. Preventive Services Task Force, an independent panel of experts whose recommendations help define high-quality preventive health care for Americans (Annals of Internal Medicine, Sept. 20, 2011). The recommendation reaffirms the group's 2004 advice.

The task force found no evidence that a screening ECG or stress test — screening means checking apparently healthy people to see if they have an undiagnosed condition — will change your cardiovascular risk classification or the way you manage your heart health. And while an ECG is one of the safest tests around, it can lead to additional tests such as an angiogram or a cardiac CT scan. Those methods come with their own risks, such as the chance of bleeding or stroke with an angiogram, and radiation exposure with cardiac CT.

Good news for heart attack victims: hospitals across the country have shaved more than 30 minutes off the time it takes to begin artery-opening angioplasty and stent placement, the best treatment for a heart attack in progress.

Hospitals use a measure called door-to-balloon time (named after the balloon used to open an artery) to track how quickly they can get a patient from his or her arrival at the hospital to the start of angioplasty. In 2005, the median door-to-balloon time was 96 minutes. At the end of 2010, it was 64 minutes (Circulation, Aug. 30, 2011). That's a remarkable improvement, prompted by efforts from the American Heart Association, the American College of Cardiology, and other organizations.

Atrial ablation, also called percutaneous pulmonary vein isolation for atrial fibrillation, is a medical procedure that uses small bursts of electricity to stop patches of heart tissue from sending out "beat now" signals that cause the upper chambers of the heart to beat fast and wildly. As part of its Diagnostic and Therapeutic Cardiovascular Procedures section, the journal Circulation has posted a video of the procedure. This particular atrial ablation was done by Drs. Gregory F. Michaud and Roy John, of Harvard-affiliated Brigham and Women's Hospital.

Blood vessel disease linked to dementia

Gorelick PB, Scuteri A, Black SE, Decarli C, Greenberg SM, Iadecola C, Launer LJ, Laurent S, Lopez OL, Nyenhuis D, Petersen RC, Schneider JA, Tzourio C, Arnett DK, Bennett DA, Chui HC, Higashida RT, Lindquist R, Nilsson PM, Roman GC, Sellke FW, Seshadri S. Vascular contributions to cognitive impairment and dementia. Stroke 2011.

Angioplasty via wrist artery safe, effective

Jolly SS, Yusuf S, Cairns J, Niemela K, Xavier D, Widimsky P, Budaj A, Niemela M, Valentin V, Lewis BS, Avezum A, Steg PG, Rao SV, Gao P, Afzal R, Joyner CD, Chrolavicius S, Mehta SR. Radial versus femoral access for coronary angiography and intervention in patients with acute coronary syndromes (RIVAL): a randomised, parallel group, multicentre trial. Lancet 2011; 377:1409-20.