Talk:Coronary artery bypass surgery

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[edit] Article name

Hi, guys. It might be a small point but I changed the intro to 'coronary artery bypass graft surgery', as this is more precise. I'd suggest a move. - Richardcavell 14:43, 25 March 2006 (UTC)

PubMed likes the shorter version more:
Google prefers the shorter version too:
MedlinePlus calls it Heart Bypass Surgery.[1]
The American Heart Association calls it coronary artery bypass surgery.[2]
Coronary artery bypass graft surgery is, perhaps, more formal. That said, the shorter version seems to be just as well understood-- and yields more hits. I think it is worth mentioning both in the title... will re-work. I oppose the move--as per above. BTW-- the article, IMHO, needs a good overhaul... if you're up to the task jump right in. I look forward to further comments and/or edits from you. Nephron  T|C 02:58, 26 March 2006 (UTC)

[edit] Graft patency

Anyone have a good reference for graft patency rates? The numbers I have are only for SVG grafts and I don't have a proper reference for where I got the numbers from. :-( Ksheka 14:23, 29 August 2006 (UTC)

Here are some reference articles for graft patency. I don't time (at the moment to sift through them, but 50% patency in 10-15 years sounds about right: 1 2 3 4. Ksheka 15:20, 29 August 2006 (UTC)
50% is what I remember off the top of my head. The important thing is really the comparison to arterial grafts, particularily the ITA--which has patency rate of something like 90% at 10 years. Surprising is-- there doesn't seem to be a meta-analysis on this (I spent a bit of time searching PubMed). Nephron  T|C 03:42, 30 August 2006 (UTC)
From what I recall in the PCI talks, there is some debate about how good ITA grafts really are. Patency of the graft itself is excellent. However, there are issues with stenosis at the anastamosis site. Definitely need some hard facts on this. Ksheka 15:33, 3 September 2006 (UTC)
That grafts fail at the distal anastomosis is fairly well known:
  • Ojha M, Leask RL, Johnston KW, David TE, Butany J. Histology and morphology of 59 internal thoracic artery grafts and their distal anastomoses. Ann Thorac Surg. 2000 Oct;70(4):1338-44. PMID 11081895
  • Leask RL, Butany J, Johnston KW, Ethier CR, Ojha M. Human saphenous vein coronary artery bypass graft morphology, geometry and hemodynamics. Ann Biomed Eng. 2005 Mar;33(3):301-9. PMID 15868720
Nephron  T|C 18:49, 3 September 2006 (UTC)

The patency rates are as follow (in decending order):

  • LIMA
  • RIMA
  • Free LIMA
  • Free RIMA
  • Radial - should quote the RAPS study by Desai, Fremes et. al. in NEJM (2005 I think). Radial grafts historically got a bad rap due to improper handling - the patency is excellent when handled with the same regard as the IMA's.
  • SVG

If I find time to track down references for this, I will insert in in the article.

So, what happens after 15 years, when the the grafts fail? Are they replaced? --89.56.190.194 (talk) 16:36, 2 April 2008 (UTC)

[edit] Double/Triple/Quad etc. terms

I came looking for information on what the difference was between a double/triple etc. bypass. I can't find any information here, not any reference to double/triple anything anywhere in the article. Seems a little odd, seeing as every time I hear someone has this surgery there is always some kind of number prefix. —Preceding unsigned comment added by 82.23.199.1 (talk • contribs) 14:26, 30 November 2006 (UTC)

Single, double, triple, quadruple -- refers to the number of coronary arteries that are bypassed in the procedure. In other words, a double bypass means two vessels are bypassed (e.g. the left anterior descending coronary artery (LAD) and right coronary artery (RCA)); a triple bypass means three vessels are bypassed (e.g. LAD, RCA, left circumflex artery (LCX)); a quadruple bypass means four vessels are bypassed (e.g. LAD, RCA, LCX, first diagnonal artery of the LAD).
There are some pictures:
Generally speaking, the higher the number the bypasses-- the longer the procedure & the sicker the patient. Nephron  T|C 04:54, 1 December 2006 (UTC)
The above sentence is directly contradicted by the article. Erb2000 00:35, 19 October 2007 (UTC)
The article is correct. The above statement was once in the article. I added the example of left main disease (with the highest risk of death) requiring only two bypasses. The above sentence is correct that more bypasses requires more time. Dlodge 02:45, 19 October 2007 (UTC)
I think Erb2000 is referring to the sicker patient bit, which I know David (Dlodge) removed at some point when I had added it to the article earlier.
More disease, that is amendable to bypass, gets a larger number of bypasses, i.e. a patient with diffuse 2 vessel disease (not amendable to PCI) ideally gets two (or more) bypasses (if technically feasible); a patient with diffuse 3 vessel disease (not amendable to PCI) ideally gets three (or more) bypasses (if technically feasible).
Dissecting the statement a bit further, cardiac surgeons often forgo grafting less dominant vessels with diffuse disease -- not considered salvageable by bypass. If you really want to pick appart the statement you have to define sicker patient, which I suppose could be done with something like the NYHA classification or the CCS classification. Examined in this respect, the article is correct; sicker patients (as defined by the CCS classification) typically don't get more bypasses.[3] Nephron  T|C 08:34, 19 October 2007 (UTC)

[edit] Clarifications

I made many changes to this article to help improve its accuracy. If there are any issues, let me know and I will explain further. You cannot talk about on pump bypass surgery without mentioning the aortic cross clamp and the perfusionist. Partial clamp grafts are done while still on bypass, so they don't reduce bypass time. Respiratory therapists do not intubate patients before surgery. Nearly all bypass surgeries use the LIMA and the saphenous vein. The other arteries are rarely used. Boyd888 23:28, 8 November 2007 (UTC)

I undid the edits. I recognize the edits were well-intentioned.
  • CRNA's are unique to the U.S - RTs do intubate patients in some OR's.
  • Proximal SVG's can can be done after the heart is restarted and bypass is stopped (all off-pump SVG proximals, T-grafts from the IMA's aside, are done with the C-clamp) - but this is not done because it is safer to remain on bypass. Many surgeons refuse to use the C-clamp in on-pump cases (and do the proximal SVG's with the cross-clamp in place) because the extra aortic manipulation increases the risk of stroke. The multiple applications of the partial occlusion clamp are probably more risky than a few extra minutes on CPB.
  • Radial arteries are commonly used - there is a lot of literature on their use (the best would be the RAPS study published by Desai et al in the NEJM). Many institutions practice total arterial grafting (TAG) - using SVG's only when the IMA's and radials have been used (some surgeons will use bilateral IMA's and radials, but bilateral radials is rare). Look up PMID:17956634 by Legare et al - 4696 CABG patients with 1019 patients undergoing TAG (22%); the raw outcomes show a mortality benefit with TAG, but this was not proven when adjusted for clinical factors. The LIMA to LAD graft has been shown to improve survival, and is the standard of care for CABG. Evidence shows radials (RAPS was the landmark study) and RIMA'a are superior to SVGs, but there is no proven mortality benefit, so it has not become the standard of care. SVG harvesting is less resource intensive (much faster and therefore cheaper than radials and bilateral IMA's) and hospitals / surgeons receive the same amount of money for CABGs done with multiple arterials vs. SVG's. Dlodge 05:28, 12 November 2007 (UTC)
There was no need to remove ALL of my edits. I see you added CRNA back in. In addition, the perfusionist is mentioned in the caption in the main article picture; that position surely deserves mention in the procedure/article itself. The way it was written made it sound like the surgeon ran the bypass machine. Heparin and Protamine are two very widely used drugs and deserve mention as well. It would also make a great addition to the article to mention some of the issues that arise from the usage of these drugs (coagulation issues, HIT, protamine reactions, etc) since they are some of the most common complications seen. Boyd888 02:02, 15 November 2007 (UTC)
Sorry about removing all of the edits. Protamine, heparin, HIT, aortic cross-clamps and procedures to institute CPB would be more appropriate on the Cardiopulmonary bypass page rather than on the CABG page. I think stating only "starting CPB and arresting the heart" is appropriate in the simplified CABG procedure. If someone is interested, they can read the specifics on the CPB page. Also the information could be easily accessible from all cardiac surgery pages rather than on only the CABG page. Dlodge 02:45, 15 November 2007 (UTC)

[edit] Prognosis

It says in the article that: " The older patient can usually be expected to suffer further blockage of the coronary arteries". There is no indication what is meant by "older". Could this be added? Aixroot (talk) 09:44, 28 January 2008 (UTC)

[edit] External links?

Why is there an external link section and no external links? 24.22.24.208 (talk) 03:55, 4 March 2008 (UTC)

Because the links that were there were deleted for being linkspam. I have now added one good external link. Dlodge (talk) 06:13, 4 March 2008 (UTC)