EP Lab Digest speaks with EP Physician Alejandro Perez Lugones, MD

It was concluded that it was equally as safe and effective in a group of patients with a left ventricular ejection fraction, averaging less than 40% as in those with normal heart function. His research was presented at this year's ACC meeting in March 2002. Research has shown that more than 80% of cases of refractory atrial fibrillation are cured by pulmonary vein isolation. For returning or further ablation, the rate is 95% success. In addition, after recovery, most patients can stop taking blood thinners. Read about his recent work in pulmonary vein isolation at the Cleveland Clinic.

Did you attend the NASPE meeting this May? What information did you see come out of this year's meeting?

Yes, I was at NASPE. I was interested in finding out more information on mapping systems; researchers are beginning to use them to be able to see how the pulmonary vein anatomical activation is related to atrial fibrillation.

How long have you have been at the Cleveland Clinic? Describe some of your work there.

I have been at the Cleveland Clinic for four years. We have been performing pulmonary vein isolation for curing atrial fibrillation. In this procedure, we use a particular mapping technique to perform isolation in patients. We have a large number of patients who have already undergone this procedure.

Is this procedure still in research stages or is it being used?

No, the procedure has been widely used. The procedure is new, but it is being used in some hospitals in the US, Europe and Asia. It is only new, in context, if you consider the technology from 2 years ago.

Describe pulmonary vein isolation for our readers.

Basically, the procedure targets atrial fibrillation that is originated into the pulmonary veins in about 94-96% of patients who are referred to the EP labs. The electrical activation of the vein follows pathways to enter the left atrium and vice versa. We insert catheters transecting the interatrial septum to get access to the left atrium and pulmonary veins. A circular mapping catheter (10 or more electrodes) is placed at the atrial venous junction level (ostium). Intracardiac ultrasound (ICE) allows us to confirm the optimal placement of the circular mapping catheter at the pulmonary vein ostium. The isolation of the pulmonary veins is achieved targeting the breakthroughs from the left atrium to the veins by means of radiofrequency (RF). The acute success rate is around 80% in experienced centers.

What are the risks associated with this procedure?

The risks depend on and are associated to transseptal puncture in most of the cases. They are less than 1% in incidence if the procedure is performed by trained hands. Another important risk to consider is stroke. However, we have found that monitoring the formation of bubbles by ICE during RF application could prevent it.

Are you currently involved in any other clinical trials at Cleveland Clinic?

No, I am not involved with other trials that is not my area of research. My specialty area is pulmonary vein isolation research and understanding mechanisms of atrial fibrillation. I am involved in novel research oriented to atrial fibrillation and the pulmonary veins.

But electrophysiology is your specialty?

Yes. I came to the Cleveland Clinic to perform research in atrial fibrillation and to transfer this research to clinical practice. My background in EP, as a clinician, allows me to understand the procedures that we do in the EP lab better than basic researchers who don t have that background. Are you only involved in research or do you still see patients? I don t perform the procedures myself. However, at the current time, I have been working extensively in studying the pulmonary vein anatomy, because this was an area not previously described, not even in anatomy books. The importance of this is that by knowing the pulmonary vein anatomy, we can really improve the accuracy of every EP mapping system that we use in the pulmonary vein and be more successful. In addition, by means of spiral computerized tomography performed in patients with atrial fibrillation and control patients without arrhythmias, we compared the anatomy of the pulmonary veins.

What kind of information about pulmonary vein isolation do you think we will see in the future?

Studying the anatomy of the pulmonary vein allows us to know what kind of mapping system would be the most accurate and the best to use in the pulmonary veins. For example, there are several mapping systems that are designed without taking into consideration the complex mapping of the vein. Knowing the anatomy allows us to choose better options for mapping pulmonary veins.

How did you get involved in the field of electrophysiology?

I am a clinical cardiologist. I began training in cardiology already interested in arrhythmias. Then, I had a fellowship in peripheric hemodynamics that allowed me to be trained in catheters, arteries and veins in the human body. After that, I began training in EP performing ablation procedures using radiofrequency. Later, I became very interested in studying the specific mechanisms of the arrhythmias.

I also have seen you have written for publications before. Do you still write or publish?

Yes. I have new discoveries in atrial fibrillation that will be published soon.

The Cleveland Clinic has long been a pioneer in the field of cardiology. What advances do you think we'll see in the field of electrophysiology in the next 5-10 years?

That is an interesting question, one that requires me to be objective. I believe that in the next few years we will be able to better understand arrhythmias and have more accurate mapping systems. We will be using more effective drugs, probably attached to antibodies which recognize certain types of cells the drugs will be targeting cells or anatomical structures that produce or perpetrate certain arrhythmias. I think we will probably be able to understand the most important cause of sudden death (ventricular fibrillation) and we will be able to prevent the initiation of ventricular fibrillation. Also important to mention is that all the stimulation devices like pacemakers and defibrillators will most likely be smaller and more efficient. It has been shown that patients after myocardial infarction who have deteriorated ventricular function have a reduced mortality if we implant defibrillators in them. However, so far the cost for this intervention in the wide spectrum of the population is extremely expensive, and there is no country that can really face it. I hope in the future defibrillators will be less costly and more widespread for everyone.