A: An electrocardiogram (ECG) records the heart’s electrical activity (heartbeat) while the echocardiogram records the mechanical or muscular activity (heart contraction). The ECG tells doctors about electrical problems that can cause arrhythmias while the echo diagnoses abnormal contractions that can cause heart failure.

A: As you are well aware, there is an extreme shortage of organs, including hearts, suitable for transplantation. In 1982, the United Network for Organ Sharing (UNOS) was formed to provide equitable distribution of transplant organs. Located in Richmond, Virginia, UNOS is a nonprofit organization that administers the Organ Procurement and Transplantation Network (OPTN) to facilitate organ matching and placement according to equitable policies based on objective medical criteria such as blood and tissue type, medical urgency of the patient, time spent on the waiting list, distance between the donor and recipient, and so on. There are about 2,500 heart transplants yearly in the U.S., with many thousands more on the waiting list. The waiting time varies from several days to several months or longer.

A: Aspirin inhibits blood clotting by reducing the “stickiness” of platelets. This helps lower the incidence 
of stroke and heart attacks, but may increase the risk of bleeding. In general, people at low risk of having a heart attack or stroke shouldn’t take daily aspirin because the chance of bleeding outweighs any potential benefit. In contrast, low-dose aspirin therapy is beneficial for those who carry an increased risk of heart attack or stroke, including people with the irregular heart rhythm called atrial fibrillation.

I came through the stroke fine because I went to the hospital right away and have been on warfarin ever since. My question is: If there’s no shunt, is the hole present?

A: The heart defect (or hole) responsible for a stroke is usually located in the top chambers of the heart, or atria. Diagnostic tests may detect an atrial septal defect (ASD) or a patent foramen ovale (PFO), both of which are “holes” in the tissue separating the right and left atria. A “shunt” is the term used to describe blood flow across such a defect. In your case, the concern is a right-to-left shunt, meaning that a blood clot could travel from the right to the left side of the heart, and then on to the brain and cause a stroke. Even if testing did not show a right-to-left shunt, it could still happen on occasion, such as after coughing or sneezing. Ask your cardiologist whether you indeed do or do not have a shunt. Treatments include closing the shunt via a device implanted during a heart catheterization (rather than open-heart surgery) or lifelong anti-coagulation with warfarin.

A: The Maze procedure is open heart surgery to eliminate rapid heartbeats. It involves making a series of incisions in the top portion of the heart, the atria. In experienced hands, the procedure is successful in more than 90 percent of patients. A far less invasive option, ablation, utilizes heart catheterization for the same purpose. While its success rates are somewhat lower (60 percent to 75 percent), catheter ablation is often recommended unless the patient is scheduled for surgery to bypass a clogged vessel or correct a valve during which the Maze procedure can also be performed.
To find an expert near you, visit hrsonline.org.

A: It is safe for your pacemaker—but it may not be safe for your wallet!

A: Bypass vessels, particularly when veins are used in contrast to arteries, can clog or narrow (note President Bill Clinton’s recent incident), but it usually occurs years after the surgery. Damage to the bypass vessel during surgery sometimes triggers early scarring. In any event, an obstructed bypass vessel can often be propped open with a heart stent, a wire mesh tunnel that is inserted with a catheter, as Clinton had done.

A: Ten premature beats per minute is a fair amount that can be perfectly harmless. However, we now know that premature beats sometimes cause heart failure and shortness of breath, and can be eliminated by a heart catheterization ablation procedure. I suggest consulting a cardiologist or electrophysiologist (hrsonline.org).

A: Severe blockages in coronary arteries can certainly cause a heart attack. Often, such blockages can be propped open with stents, which can relieve the angina. When people have good collateral circulation (new blood vessels bypassing the blocked ones and supplying the heart with blood), then nothing further may need to be done. Imdur (isosorbide mononitrate) helps relieve angina, Taking aspirin, a statin, an ACE inhibitor, and a beta blocker may be recommended, too.

A: It is always a good idea to get another opinion, especially when 
it comes to surgery. After all, it is 
your body, and you want to be sure the decisions made are the absolute best for you. Ask your doctor for another recommended cardiologist 
or visit the American College of Cardiology Web site (acc.org) to find someone near you. 

Blood Pressure Boosters

A: Unlike warfarin, a blood thinner used for decades that is regulated by blood tests, the experimental drug dabigatran prevents blood clots with a fixed dose that is taken twice daily. The FDA approval of dabigatran, the first of a new class of drugs called direct thrombin inhibitors, is expected sometime this year.

Q: A doctors says our neighbor died in his sleep of a massive heart attack. Could a defibrillator have saved him?

A: While it is possible your neighbor did have a heart attack, the event that likely killed him was an abnormal heart rhythm called ventricular fibrillation. You do not give your neighbor’s age, but assuming he/she was an adult, a heart attack could have triggered the VF. The usual heart rate at rest is around 70 beats/min. During VF, the ventricular rate surges to 400-600/min, preventing effective contraction of the major pumping chambers that deliver unoxygenated blood to the lungs (right ventricle) and oxygenated blood to the rest of the body (left ventricle). The ventricles during VF look like a bag of squiggly worms, a belly dancer gone berserk. With no blood flow to the brain, loss of consciousness occurs in 10 to 20 seconds and death in five to eight minutes. Sudden cardiac arrest occurs almost 1,000 times per day in the U.S., claiming the lives of half of those who have heart attacks before they reach the hospital. It is likely that prompt use of a defibrillator to shock the heart rhythm back to normal could have saved his life.

A: Your husband isn’t alone—most people with high blood pressure have “essential” hypertension, which means that there is no identifiable cause for it. One promising experimental therapy involves threading a catheter into the artery that provides blood to the kidney, and then delivering electricity via electrodes at the end of the catheter to “burn” certain nerves in the arterial wall that play a key role 
in the development of hypertension, 
an approach that may restore normal blood pressure without using drugs.

When you are at rest in a warm bed, arteries dilate and blood pressure tends to be low. When you stand up, your body elevates blood pressure to be sure your brain is perfused so you don’t black out. Getting out of bed in a cold room could cause an increase in pressure. How high does it get when you stand up? Does it then return to normal? Is your blood pressure cuff accurate? Discuss these questions with your doctor.

Both of your doctors could be right. It depends on where the calcium is, how much is there, and whether it is buried in the heart muscle or mobile, like in a valve leaflet. If it is immobile, it may not be necessary to remove because it is anchored in place and may not be causing any problems.

If it is moving, it may be susceptible to breaking off into the bloodstream, and its removal might be a priority. Be bold and ask both doctors to explain their positions. Having a significant leak in your valve could be a reason for operating to try to fix it.

A: I am concerned about your symptoms during walking up a flight of stairs or on streets with an incline. At the very least, I would recommend you consult a cardiologist and undergo a stress test to see if any abnormalities are provoked.

A: Skeletal muscles in your arms and legs need oxygen and can produce pain if they do not get enough of it. However, pain in the arm, neck, jaw, shoulder, and back because of coronary artery obstructions (which I assume led to your open-heart surgery and stents) is thought to be “referred” from the heart itself because of the lack of oxygen to the heart muscle. I agree that your next step is to have a stress test to determine if you have remaining coronary artery obstructions.

A: What you describe is not common, though it unquestionably happens. Unfortunately, atrial fibrillation generally recurs unless the factors that first produced it are no longer present — for example, a narrowed heart valve is replaced by a prosthetic one, or hypertension that made the heart work harder is now under control. Another factor to consider is that having AF actually changes or “remodels” the atrial heart muscle into tissue more conducive to having AF. However, the reverse is true also.

Having a normal rhythm can help reverse the remodeling and deter future AF recurrences. You are most fortunate, and I hope the normal rhythm continues. Do let me know what happens.

A: I am not aware of the information you cite. In fact, the body tightly regulates its pH (a measure of the acid-base balance) between 7.35 and 7.45. For example, if your blood becomes too acidic, a condition called metabolic acidosis, the body compensates by breathing more rapidly to exhale carbon dioxide and return the pH to normal limits. I am also not aware of a way to achieve an alkaline system that the body will not attempt to rebalance to normal. Nor am I aware that such an alkaline system would be better for the body’s organs.

A: The pacemaker or its wires may stand out due to your having little body fat or because of where the pacemaker was implanted. I would not worry about it as long as the skin over the wires and the pacemaker does not get red and sore and the area does not get rubbed or bumped often. While the implant can
be revised and buried deeper, it is best to “leave well enough alone.” Any revision carries some risk, particularly of infection. So avoid that if possible. The best news is that the pacemaker is preventing your passing-out spells.

A: Sinus bradycardia with rates as low as you describe can be a completely normal finding. I exercise a lot, and my heart rates are just about like yours. Well-conditioned athletes have resting heart rates in the 30s. Generally, we only treat sinus bradycardia (usually with a pacemaker implantation) if the individual is symptomatic from the slow rates. Since you say you are doing fine, I would recommend not doing anything except for following up with visits to your cardiologist maybe once or twice a year for a checkup. Should you experience dizziness, a lightheaded spell, or loss of consciousness, tell your doctor immediately because a pacemaker may be indicated at that time.