RAY SUAREZ: For more on the problems, tests, and treatments affecting Vice President Cheney, we're joined by Dr. Cynthia Tracy, interim chief of the cardiology division at Georgetown University Hospital.
Well, Doctor, you heard the Vice President tell reporters that these incidents of arrhythmia just occur for a few seconds at a time every now and then. What is it that makes irregular heartbeat serious in the first place?
DR. CYNTHIA TRACY: It entirely depends on the status of the heart, what condition the heart is in. You or I might be having those very same type of heartbeats right as we're sitting here talking and also not have any symptoms related to them. The difference is that we have normal heart function -- have not had heart attacks and do not have sort of depressed function related to a heart attack. So what in us would be a very benign condition, in someone who has this profile of lowered heart function and prior heart attack, this becomes not itself a serious rhythm, but maybe a warning for something that's potentially quite serious.
RAY SUAREZ: Now the heart, depending on what else is going on in the rest of your body, routinely speeds up or slows down. What is it about these little periods of irregular beat that makes it a danger to the body?
DR. CYNTHIA TRACY: These beats are not coming from the normal part of the electrical system. They're coming from the bottom chamber of the heart or the ventricle. The beats usually start at the top and work their way down. These beats, on the other hand, are coming from someplace other from where they should be; they're coming from the ventricle or the main pumping part of the heart. So alone three or four beats of ventricular tachycardia are not significant but if it were to sustain into something that went on for an extended period of time, it could result in a sudden death episode or a cardiac arrest.
RAY SUAREZ: Now, the Vice President wore one of these monitors, a heart monitor.
DR. CYNTHIA TRACY: That's right.
RAY SUAREZ: What would his doctors have been looking for?
DR. CYNTHIA TRACY: On the halter monitor you're essentially looking for any evidence of abnormal heart rhythms occurring. And this device is fixed with-- it's a very simple device really; it has basically a tape in it that records the heartbeats for 24 hours, in some cases you want to extend it beyond 24 hours. This device is just worn under routine activity. The person does what they ordinarily do during their day, and it has then the ability to be played back into essentially a computer system that looks at every single heartbeat and determines whether there are any of these abnormal beats occurring and whether they're occurring in sequence.
That's sort of the critical differentiation. A few abnormal beats here and there don't really amount to much but in somebody such as Mr. Cheney who has a lower ejection fraction, if they sling themselves together, that's the potential warning sign for danger.
RAY SUAREZ: So the bar is at a different place for a man who has had four heart attacks?
DR. CYNTHIA TRACY: Exactly.
RAY SUAREZ: Okay, so the solution or one of the solutions they're talking about is this device. Tell us about it.
DR. CYNTHIA TRACY: Right. This is one of the types of implantable defibrillators that's available today for use in people who are at risk for sudden death. And this device is a very elegant little piece of machinery. It essentially is sitting quietly monitoring what the heart rhythm is up to at all times.
It's not doing much of anything unless it's called into action. If it detects an abnormal heart rhythm, it can then deliver different types of treatment; it can either pace the heart -- capture the electrical activity the same way a person with a permanent pace maker captures the heart, or if that's unsuccessful at getting the heart back into a normal rhythm, it can deliver a higher energy electrical shock, which then interrupts -- more aggressively interrupts the abnormal heart rhythm and allows the heart to go back into a normal rhythm.
RAY SUAREZ: So, as we've discussed these periods of irregular rhythm, in his case, episodic, occasional, would this device be willing to overlook the odd one here and there and only intervene when it sees that there is a pattern of this? Is it immediately called into action whenever it senses anything's wrong?
DR. CYNTHIA TRACY: No, it absolutely would do nothing for the three or four beats that apparently Mr. Cheney demonstrated on the Halter monitor. It is programmed, told what is it that you need to treat. How fast does the heart have to be beating in order for it to be recognized as an abnormal rhythm. How long does that have to go on for?
So it is not going to do anything other than know that these abnormal beats occurred. If it detects something that is potentially threatening, it will then treat it. These are lovely devices. You can set up how aggressively the device treats, depending on what it sees in terms of heart rhythm. So it is pretty sophisticated. It's like having a little doctor with you at all times.
RAY SUAREZ: Is this something that we assume a patient would then wear in some form for the rest of their lives?
DR. CYNTHIA TRACY: Yes, in general once a decision has been made to implant a device like this, it is in recognition of the fact that there is a condition that is potentially life threatening and it's not anticipated that that would ever correct itself. So, yes, you would anticipate the person requiring a device like this for the rest of their life.
RAY SUAREZ: And how does your life change once you have one in? Are you able to follow your normal routine, do the things you would have done before?
DR. CYNTHIA TRACY: Fortunately nowadays because the devices are so sturdy and stand up so well to normal activities, yes, a person can go about their normal duties and normal activities very easily and very comfortably with one of these implanted. The device is implanted under the clavicle usually over on the left side. It just makes a very small bump under the clavicle, underneath the skin. So everything is self-contained and does not require any type of unusual-- I don't know, other accoutrements.
It requires routine follow-up and visits to the electro physiologist; that's a heart specialist who deals with heart rhythm problems -- follow up to interrogate or question the device. What have you seen seeing ? Have you been required to give any treatment? What is the battery status on this device? When will this battery need to be replaced? There are certain things that an individual with a device like this will need to avoid. One of those would be some types of higher energy diagnostic studies where big magnets are used or avoiding high electromagnetic fields. Probably shouldn't bend over into an airplane engine or something like that with one of these devices in place.
But it is easy to test an environment. The companies that manufacture the devices are happy to come and test any environment that a person is working in. And we have people fitted with these devices who are engaged in any numbers of types of activities and professions.
RAY SUAREZ: What should a man in Dick Cheney's general condition take away from this kind of warning?
DR. CYNTHIA TRACY: Well, you know, I think that he should be happy that he's got doctors who are watching him so closely. They're doing exactly what they need to be doing at this point. He is going along with their advice, I think appropriately. He needs to be aware that this is a serious condition. It's not something that's undertaken trivially.
But obviously he is aware of that and is following medical advice carefully. I think he just needs to keep being honest and open the way he is with the American public. He is doing a tremendous service to people by being this open about this condition. The number of people who could benefit from this device is a lot larger than the number of people who have this device implanted.
RAY SUAREZ: So if you've got any indication that something is wrong, seeing the Vice President might send you down to your own doctor?
DR. CYNTHIA TRACY: Hopefully it will. I think this is something that people need to be aware of. He does not-- he has not collapsed. He has not had any type of direct life threatening heart rhythm. He is a man who is responding and his doctors are responding to a potential threat. And it's important, I think, to get that message out to doctors and to patients that there are potential things out there that could affect your health. It is appropriate to do the correct screening. If it is necessary, to go on to the steps such as implanting a device like the defibrillator.
RAY SUAREZ: Dr. Tracy, thanks a lot.
DR. CYNTHIA TRACY: Thank you.