Freezing the heart to heal the heart

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DELRAY BEACH, Fla. (Ivanhoe Newswire) -- Atrial fibrillation causes the heart to contract in a very fast, irregular way. It affects about three million Americans and can lead to heart failure or stroke. Now — there’s a new treatment that literally freezes AFib away, when medications don’t work.

When it comes to spending time in her garden, Carmen Winkler doesn’t skip a beat.

“I like my flowers,” Carmen told Ivanhoe.

But her love was threatened when her own heart began to flutter.

“It was so hard, my blouse was moving,” Winkler said.

Her doctor diagnosed her with atrial fibrillation.

“Atrial fibrillation is a fast irregular heart rhythm from the top chamber of the heart and it affects about 15 percent of the population,” Jonathan Rosman, MD, Cardiologist, Delray Medical Center, told Ivanhoe.

When medication fails, Dr. Rosman says radiofrequency ablation is used, where heat destroys the tissue causing the irregularity.

“However, what can happen is you can actually burn a hole through the heart and it can go into the esophagus and that can be fatal,” Dr. Rosman said.

Now, a new option virtually eliminates that risk by freezing the tissue instead of heating it up.

“By freezing, we’re no longer destroying the tissue. What we are doing is making it electrically inactive,” Dr. Rosman said.

A small catheter injects a liquid coolant into the affected area, freezing the tissue and restoring the heart’s rhythm.

Now, Winkler is back to admiring her butterflies just one month after her procedure.

“Once we had 80 butterflies,” Winkler said.

Cryoablation has been found to be less likely damage heart tissue than radiofrequency ablation

 BACKGROUND: Atrial fibrillation (AFib) is a quivering or irregular heartbeat that can eventually lead to stroke, blood clots, heart failure, and other heart-related complications.  Approximately 2.7 million Americans are suffering from AFib.  A normal heart contracts and relaxes to a regular beat, but in AFib the upper chambers of the heart (the atria) beat irregularly (or quiver) instead of beating normally to move blood into the ventricles.  Around 15 to 20 percent of people who have strokes have this heart arrhythmia.  When blood is allowed to slow down or pool, it increases the risk of clotting and also increases the risk of stroke.  According to the 2009 “Out of Sync” survey, only 33 percent of AFib patients think it is a serious condition, even though it is called the most common “serious” heart rhythm abnormality in people over the age of 65.  (Source:


SYMPTOMS:  Sometimes people with AFib do not have any symptoms and their condition is only detectable through a physical examination.  However, others may experience: rapid and irregular heartbeat, dizziness, fluttering in the chest, weakness, shortness of breath and anxiety, faintness or confusion, sweating, chest pain or pressure, and fatigue when exercising. (Source: Risk factors can include age, a family history, cardiovascular or lung disease, and chronic health conditions.  Some lifestyle factors can increase the risk of AFib including stress, smoking, stimulant drugs like caffeine, and alcohol abuse.  (Source:


NEW TECHNOLOGY: The most common procedure to treat AFib is called thermal ablation. Surgeons go into the heart and, using extreme heat, destroy the circuits that are causing the atrial fibrillation. The procedure though, can be risky. Although rare, there is a risk that the heat can burn a hole too deep into the heart, and it can go into the esophagus, which is located right behind the heart. This can be fatal if not recognized immediately. Instead of using heat, doctors are now using extreme cold to stop AFib. A balloon catheter goes into the heart, expands, and fills with a coolant. The extreme cold doesn’t destroy the circuits like the heat does, but instead makes it electrically inactive. Patients generally have a 70 to 85 percent success rate following the procedure. (Dr. Jonathan Rosman)


Jonathan Rosman, M.D., Clinical Cardiac Electrophysiologist at Delray Medical Center, talks about a new cryoablation procedure for treating atrial fibrillation.

What is atrial fibrillation and how big of a problem is it?

Dr. Rosman: Atrial fibrillation is a fast irregular heart rhythm from the top chamber of the heart and it affects almost 15 percent of the population when you hit a certain age. The biggest problem and risk for people who develop atrial fibrillation is the risk of stroke. People are usually on blood thinners to minimize the risk of stroke. However, people usually don’t feel well when they’re in atrial fibrillation, the heart usually races, goes quickly, people can feel all sorts of things: lightheaded, dizzy, short of breath, less energy, palpitations, and fatigue. For that reason you try to keep patients in normal rhythm instead of this irregular erratic rhythm. So there are different ways of doing it and what we initially do is try to cardiovert them or zap the heart back to normal rhythm. But what that does is just reset the heart; it doesn’t do anything to the underlying problem. So what we do is we have medications that target the areas that cause the atrial fibrillation and try to stop the atrial fibrillation from coming back. Unfortunately, in a significant number of people medication is insufficient. The medications don’t always work at stopping the atrial fibrillation so in those patients there is a procedure that we do where we can eliminate the triggers and eliminate where the atrial fibrillation is coming from so that they can be free of the disease and free of the atrial fibrillation, sometimes without even needing any medications.

So the most common procedure is heat ablation?

Dr. Rosman: Correct. So there are currently two types of ablations.

What exactly is happening in the actual heart during atrial fibrillation?

Dr. Rosman: In the heart, there are two top chambers and there are two bottom chambers. The top chambers pump blood to the bottom; the bottom chamber on the right pumps blood to the lungs to get oxygen and on the left it pumps the blood with the oxygen to the rest of the body. So the normal electricity to the heart starts in the right upper chamber, and tells the two top chambers of the heart to beat usually between 60 and 100 times a minute. The electricity then goes down to the bottom chambers and tells the bottom chambers to follow suit. So that’s the normal conduction, normal rhythm. What happens with atrial fibrillation is there are little veins in the left upper chamber of the heart that come back from the lungs and they’re little sleeves of tissue that go extend from the left upper chamber into these vessels and that’s where atrial fibrillation is usually coming from. So the electricity from these vessels start firing anywhere between 400 and 600 times a minute and cause a very irregular, erratic, fast heartbeat that conducts in the top chambers very quickly and then down to the bottom chambers as well. So the bottom chambers can’t go that fast but it can still go very quickly. And because the bottom chambers go quickly that’s what you feel. And there are little crevices in here and blood can coagulate and form a clot. And that can increase the risk of stroke and that’s why patients need to be on blood thinners. The second problem is because it’s going so fast what we feel is really the bottom chamber, but the bottom chamber also is going very fast and it’s not a normal rhythm patients just don’t feel well. Again lightheaded, dizzy, fatigue, short of breath, palpitations, decreased energy and for that reason we want to try to keep them in normal rhythm.

Can you talk about the need for a new procedure and some of the drawbacks that the heat ablation has?

Dr. Rosman: What has always been done for this procedure is to use heat to try to eliminate the circuits that are causing atrial fibrillation. What we do is we make a circular lesion so that we basically destroy tissue around the veins so anything that starts in the vein will hit that tissue where we’ve destroyed and it will stay in the vein. So the atrial fibrillation will no longer be able to enter the heart and cause the patient atrial fibrillation. So one of the drawbacks to the heat or radiofrequency ablation is that you’re actually destroying all that tissue, by heating it up you’re destroying all the tissue that is there. And what can happen, although it is rare, is the feeding tube, the esophagus, sits right behind the left top chamber of the heart where we are burning. And what can happen is you can accidentally burn a hole through the heart and it can go into the esophagus and you now establish a communication between the heart and the esophagus and that can be fatal. That is a much feared complication, and if not recognized immediately those patients often do die. So although it is not common, it does happen with radiofrequency ablation.

Well that one doesn’t always work either, does it? Sometimes you might have to have it done again?

Dr. Rosman: The success rate of the procedure for patients who have on and off atrial fibrillation called paroxysmal atrial fibrillation is about 70 to 75 percent for one procedure. And there are times where you will need a second procedure and then the success rate will increase between 85 and sometimes even 90 percent. The reason for the newer procedure called cryo-balloon or freezing ablation, where instead of burning out the circuits, we freeze the area, was not so much because of the success rates, because the success rates are actually pretty similar between the two, it’s more of the safety concerns. The biggest concern was always that we can burn, by destroying tissue you’re causing more damage and by doing that we can potentially have more complications and the feared one is this connection between the heart and the esophagus. by freezing we’re no longer destroying the tissue; what we’re doing is making it electrically inactive. We’re removing the heat from the area which no longer allows it to conduct electricity. So again everything that starts from the vein with atrial fibrillation will stay there because it can no longer enter the heart. But it’s no longer destroying that tissue. Cryoballoon ablation has been used for years and we really have not seen this feared complication at all, whereas we continue to see it with the radiofrequency or the burning ablation. As far as the success rate the success rates are actually pretty similar.