| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||
Ann Thorac Surg 1995;59:287
© 1995 The Society of Thoracic Surgeons
DR ROBERT A. GUYTON (Atlanta, GA): Doctor Boylan, that was a beautifully presented paper.
Doctor Joe Craver put together our experience over this same decade several years ago. In this interval we also had some 10,000 patients undergoing angioplasty. Our failure rate, or the number of patients who arrived in the operating room, was 5.9%, which gave us more than twice as many patients to analyze as the Cleveland Clinic group. When the surgeons add up the number of patients arriving in the operating room it somehow seems to be a little different than the number of patients that the cardiologists send out of the catheterization laboratory after a failed angioplasty.
Eighty-two percent of these patients had ischemia when they arrived in the operating room; 18% did not. The mortality for the patients with ischemia was 6%; for patients without ischemia it was 1%. Probably because we had more patients and because we had more patients in the early 1980s who had single-vessel disease with good ventricles, we did see a significant difference as far as death was concerned in the thirds of the decade, increasing from 0.05% to 2.5% to 7% over the decade.
The reasons for this were related to a change in the nature of the patients coming from the catheterization laboratory. More than twice as many patients were older than 60 years, twice as many patients had a low ejection fraction, twice as many patients were diabetic, one and a half times as many patients were hypertensive, and almost twice as many patients had multivessel disease.
In particular, multivessel disease seemed to make a difference in our hands. In patients with single-vessel disease the incidence of stroke was 0.5% and the death rate was 1.5%. With multivessel disease the stroke rate was 2% and the mortality was some 6%. So we did see a difference, perhaps related to a larger cohort of patients for analysis and, again, because we had more of the simpler patients in the early part of the decade.
My questions to Dr Boylan would focus on three things. First, when we have an angioplasty failure, particularly in an ischemic patient, we tend to change our cardioplegia technique to take advantage of methods of myocardial resuscitation, using continuous aerobic cardioplegia. Do you alter your protection techniques for these patients?
Second, your use of the internal thoracic artery is clearly different in these patients, at 22%, than it is in your elective patients. Doctors Loop, Lytle and Cosgrove have made me feel very guilty when I do not use an internal thoracic artery. Why do you use so few internal thoracic arteries in this group of patients?
Finally, I would ask about a very difficult subgroup of patients, the patients who have had prior coronary artery bypass whose condition deteriorates after a failed angioplasty and who are hemodynamically unstable. This is the one subgroup of patients in whom I believe that the use of a portable cardiopulmonary bypass system might be appropriate. I have done so in several patients with good results. Do you have data on this subgroup, and how do you manage them?
DR BOYLAN: Thank you for your comments, Dr Guyton, and for sharing your data with us. With regard to cardioplegia and surgical techniques in general, moderate systemic hypothermia and antegrade cardioplegia were employed during most of the years of this study. In the later years of the study, retrograde cardioplegia was introduced and has become standard. The use of blood versus crystalloid cardioplegia and warm induction cardioplegia has varied among surgeons and was not standardized.
Your comments about the use of the internal thoracic artery are very pertinent. We agree that the use of the internal thoracic artery should be a standard part of most revascularization operations. However, in these emergency settings, our use of the internal thoracic artery has been less consistent. Reasons for not using this conduit included a desire to minimize the ischemic time after acute coronary occlusion, concerns about adequacy of flow to a large coronary artery that has been occluded acutely, and concerns about using the internal thoracic artery with associated extensive disruption or dissection.
Your third question dealing with how those patients should be managed in the angiography suite before coming to the operating room is a problematic one, and specifically in the case of redo patients. The CPS system was not used for the patients in this study, although now it is used occasionally. Almost all mortality in this series was related to myocardial damage. It is not clear to what extent the CPS can or will decrease infarct size, particularly for patients with acute occlusion of major vessels. One potential danger of CPS is a false sense of security it may give to the interventional cardiologist with a resultant delay in operating and a delay in relieving ischemia in the setting of acute occlusion.
Although we did identify a specific increased risk for patients with a previous bypass operation, this is in part related to judicious selection of these patients for angioplasty. Certainly when an emergency situation arises for these patients it is a difficult problem. Angioplasty back-up for these patients may include holding an operating room on stand-by, and recent experience with CPS. However, the results have been mixed. With large numbers of patients who have had previous bypass operations now presenting with recurrent ischemic syndromes this issue will become more significant.
Related Article
Ann. Thorac. Surg. 1995 59: 283-286.
| ||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
