• Users Online: 173
  • Print this page
  • Email this page


 
 
Table of Contents
CASE REPORT
Year : 2019  |  Volume : 2  |  Issue : 4  |  Page : 330-333

One-year angiographic results of left anterior descending bypass using internal mammary artery: a series of 48 consecutive patients


Department of Cardiac Surgery, National Heart Institute, Cairo, Egypt

Date of Web Publication10-Feb-2020

Correspondence Address:
Ahmed S Mahlab
Department of Cardiac Surgery, National Heart Institute, Cairo
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/JMISR.JMISR_62_18

Rights and Permissions
  Abstract 


The left internal mammary artery (LIMA) has been used as a conduit for coronary artery revascularization since 1968. Here we are reporting A total of 48 consecutive patients were operated upon using double mammary arteries. All of them received a mammary graft to the left anterior descending artery (LAD). All 48 of them were controlled angiographically at 1 year postoperative to ensure satisfactory well-functioning grafts.

Keywords: Angiography, internal mammary artery, left anterior descending


How to cite this article:
Mahlab AS. One-year angiographic results of left anterior descending bypass using internal mammary artery: a series of 48 consecutive patients. J Med Sci Res 2019;2:330-3

How to cite this URL:
Mahlab AS. One-year angiographic results of left anterior descending bypass using internal mammary artery: a series of 48 consecutive patients. J Med Sci Res [serial online] 2019 [cited 2020 Apr 6];2:330-3. Available from: http://www.jmsr.eg.net/text.asp?2019/2/4/330/278070




  Introduction Top


However, the using of the left internal mammary artery (LIMA), as a conduit for coronary artery revascularization since 1968[1], has become regular and frequent in the last two decades as its long-term benefits have become apparent [2–4]. Several studies have also shown improved long-term patency As patients with LIMA had better long-term survival, have fewer late myocardial infarctions and sustain a greater cumulative event-free survival. In the past, some doubts have been raised about the in-hospital outcomes and morbidity in patients who received LIMA compared with those who have received vein grafts. However, there have been several studies illustrating that the early outcomes are as good as, if not better, in patients who received LIMA [5–7]. Whereas the worldwide trend in the last two decades has been a steady increase in the usage of LIMA, not much is documented about the reasons for not using LIMA. it would be appropriate to consider LIMA to be the “gold standard” conduit of choice for surgical revascularization of the left anterior descending artery (LAD)[8].


  Materials and Methods Top


A total of 48 patients were operated consecutively between May 1989 and June 1990, using bilateral mammary arteries, the left internal mammary artery (LIMA) bypassing the left anterior descending artery (LAD) in 45 of these patients, whereas Right internal thoracic artery (RIMA) was used to bypass the LAD in three of these patients (RIMA in situ).

  1. The mean age of the patients was 56.7 years (38–66 years).
  2. The male to female ratio was 42/6.


The preoperative symptoms were as follows:

  1. Angina:


    1. Stage II: 13 (27%).
    2. Stage III: 17 (35.5%).
    3. Stage IV: 18 (37.5%).


  2. Dyspnea:


    1. Stage II: 3 (6.2%).


  3. Palpitation:


    1. 2 (4.2%).


  4. Syncope:


    1. 1 (2%).


In this group of patients, the risk factors were as follows:

  1. Hypercholesterolemia: 31 (64.5%).
  2. Smoking: 22 (46%).
  3. Arterial hypertension: 21 (43.7%).
  4. Diabetes: 4 (8.3%).
  5. Obesity: 18 (37.5%).
  6. Family history: 7 (14.6%).


A total of 23 (47.9%) of these patients had a history of previous myocardial infractions:

  1. Inferior: 14 (29.2%).
  2. Anterior: 5 (10.4%).
  3. Lateral: 4 (8.3%).


Coronary angiography showed the following:

  1. 14 (29.1%) with left main disease.
  2. 12 (25%) with two-vessel disease.
  3. 36 (75%) with triple-vessel disease.


Only one (2%) patient had ejection fraction (EF) less than 35%, five (10.4%) patients had EF between 50 and 60%, and 16 (33.6%) patients had EF above 60%.

Historical aspects

In 1964, Spencer[1],[2] was the first to use LIMA in coronary artery bypass grafting (CABG) in a controlled operative field, using hypothermic cardiac arrest, ensuring good long-term results.

In 1967, Kolessov[3] published on six cases of CABG using LIMA to LAD.

Green et al.[4],[5] were the first to publish on a clinical series of LIMA to LAD in 1968 with excellent follow-up in 1970.

It is now clear that the systematic use of LIMA to bypass the LAD is accepted widely by the medical community[6],[7],[8],[9].

Venous graft results

At 6 months, the occlusion rate of one venous graft per patient is 18.2%[10].

By the end of the first year, the rate of occlusion ranges from 16 to 26% and for the distal anastomosis, it ranges from 41 to 47% per patient[11],[12],[13].

By the end of the first to the firth year, the occlusion rate ranges from 1 to 3%, reaching up to 4–5% per year; after the fifth year, this reached up to 54% at 10 years in the veterans administration study[11].

The mechanisms of deterioration of venous grafts are well known:

  1. The platelet activation phase corresponding to the initial healing phase of the anastomosis because of the mechanical alterations of venous and arterial endothelia as well as the surgical manipulation are the main causes of precocious occlusion, especially at the distal anastomosis site.
  2. The neointimal proliferation phase, which lasts for the first year (graft disease). This is accompanied by major alterations in the functional capacity of the graft.
  3. The long-term phase, depending on the risk factors common to coronary artery disease, especially uncontrolled hypercholesterolemia[10].


Factors related to better long-term patency of internal mammary arteries grafts

The short-term patency of LIMA to LAD approaches 95%, whereas long-term patency approaches 90% (1 year)[14],[15],[16],[17].

This may be because of the following reasons:

  1. Small-caliber graft, matching the coronary artery caliber, resulting in faster flow with less stasis than in venous grafts, as well as less vascular turbulence because of a negligible geometric transition between the graft and the coronary artery.
  2. In addition, mammary arteries do not have valvules or varicosities.
  3. Also, its collagenous parietal structure can adapt to arterial pressure[18],[19].
  4. Also, the incidence of atherosclerosis in the mammary artery is very low[20],[21].
  5. Also, the mammary artery is a living graft[22],[23].
  6. In an anatomical study, Landymore et al.[24] reported that the mammary artery has little vasavasora, and depends on its nutrition by endoluminal diffusion, thus conserving the biological procedure of its nutrition after its usage as a graft, in contrast to venous grafts, which depend in their nutrition on vasavasora delivering oxygenated blood to their wall.


Potentially vital vascular mechanisms contributing toward better patency of mammary grafts are as follows:

  1. Maintenance of vasomotor activity[25].
  2. The ability to dilate according to myocardial needs of blood flow[22].
  3. Preservation of endothelial integrity producing prostacyclins endothelium-derived relaxing factor (EDRF) and fibrinolysins[26],[27].
  4. The ability of the mammary artery to maintain a coronary-like flow (diastolic flow) proved by Doppler and late angiographic controls [20],[21],[22],[23],[24],[25],[26],[27],[28],[29],[30].



  Results Top


  1. A total of 48 consecutive patients received 48 mammary in-situ grafts to LAD; 45 of these patients (94%) had LIMA to LAD and three (6%) had RIMA to LAD because of failure of harvesting LIMA.
  2. All patients underwent double mammary harvesting.
  3. Two (4.5%) patients were reopened because of bleeding.
  4. One (2.2%) patient was reopened 2 weeks after the operation because of hemopericardium.
  5. Only one patient needed prolonged extracorporal circulation (ECC) assistance and was weaned off bypass using an intra-aortic balloon.
  6. Two (4.5%) patients needed the temporary use of a pace maker.
  7. Four (8.3%) patients needed prolonged inotrope infusion of more than 24 h because of low cardiac output.
  8. Six (13%) patients developed AF that did not affect hemodynamics.
  9. Three (6.5%) patients developed sinus tachycardia.
  10. Two (4.5%) patients had ventricular extrasystoles that required an infusion of rhythm control drugs.
  11. Four (8.3%) patients had perioperative myocardial infarction (MI), two of them in a nonbypassed territory.
  12. One (2%) patient developed temporary right phrenic palsy.
  13. Three (6.5%) patients had sternitis and were treated surgically as early as diagnosed.
  14. One (2%) patient had a stroke and developed left regressive hemiplegia.
  15. All patients had clinical and noninvasive controls at 3, 6, and 12 months.
  16. All patients had angiographic control at 1 year to examine the angiographic results of all grafts.


The aim of this work was to analyze the mammary grafts to LAD angiogarphically at 1 year:

  1. A total of 43 (89%) patients had angiographically perfect grafts to LAD (43 LIMA and 1 RIMA).
  2. One patient (RIMA to LAD) had anastomotic stenosis, yet patient graft.
  3. Two (4.5%) patients (LIMA to LAD) showed string sign of the graft.
  4. Two (4.5%) patients had totally occluded grafts (RIMA to LAD, the other one LIMA to LAD).


Analysis

In this series, mammary grafts to LAD had a patency rate of 95.5% (46 patients).

We had two occluded grafts to LAD.

On examination of the coronary angiography of the two patients with string effect as well as one of the obliterated grafts, we found that the initial lesions were insignificant, creating a competitive flow countering the graft flow. We attribute this either to initial overestimation of the severity of the lesion (poor indication) or to regression of lesions postoperatively by strict control of risk factors, especially the aggressive use of statins.

In brief, out of 48 mammary grafts to LAD, only 4.5% were totally occluded (two patients), whereas 46 (95.5%) grafts were patent, of which three (6.6%) grafts were unsatisfactory.


  Conclusion Top


The routine use of mammary grafts, especially LIMA, is mandatory to bypass the LAD.

Double mammary harvesting did not increase the risk of sternitis in this series, neither the risk of postoperative bleeding, taking in consideration doing a thorough hemostasis.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Spencer FC. The internal mammary artery: the ideal coronary bypass graft? N Engel J Med 1986; 314:50.  Back to cited text no. 1
    
2.
Spencer FC, Eiseman B, Yong NK, Prachuabmoh K. Experimental coronary arterial surgery with hypothermia and cardiopulmonary bypass. Circulation 1964; 29:Suppl-140.  Back to cited text no. 2
    
3.
Kolessov VI. Mammary artery – coronary artery anastomosis as method of treatment for angina pectoris. J Thovac Cardiovasc Sur 1967; 54:535.  Back to cited text no. 3
    
4.
Green GE, Stertzer SH, Gordon RB, Tice DA. Anastomosis of the internal mammary artery to the distal left anterior descending coronary artery. Circulation 1970; 41(5s2):II–79.  Back to cited text no. 4
    
5.
Green GE, Stertzer SH, Reppert EH. Coronary arterial bypass grafts. The Annals of Thoracic Surgery 1968; 5:443–50.  Back to cited text no. 5
    
6.
Bashour TT, Hanna ES, Mason DT. Myocardial revascularization with internal mammary artery bypass: an emerging treatment of choice. American Heart Journal 1986; 111:143–51.  Back to cited text no. 6
    
7.
Gibson CF, Loop FD. Choice of internal mammary artery or saphenous vein graft for myocardial revascularization. Cardiology 1986; 73(4-5):235–41.  Back to cited text no. 7
    
8.
Speiser K, Rothlin M, Turina M. Comparison between internal mammary artery implantation and aorto-coronary vein bypass grafting in coronary artery disease with significant left anterior descending stenosis. The Thoracic and Cardiovascular Surgeon 1983;31:54-7.  Back to cited text no. 8
    
9.
Spencer FC, Yong NK, Prachuabmoh K. Internal mammary-coronary artery anastomoses performed during cardiopulmonary bypass. The Journal of Cardiovascular Surgery 1964;5:292.  Back to cited text no. 9
    
10.
Ollivier JP. Study of the permeability of aotocoronary bypass at 6 months: French multicenter study. Archives of Diseases of the Heart and Vessels 1991; 84:537–42.  Back to cited text no. 10
    
11.
Bourassa MG, Fisher LD, Campeau L, Gillespie MJ, McConney M, Lesperance J. Long-term fate of bypass grafts: the Coronary Artery Surgery Study (CASS) and Montreal Heart Institute experiences. Circulation 1985; 72(6 Pt 2):V71–8.  Back to cited text no. 11
    
12.
Chesebro JH, Fuster V, Elveback LR, Clements IP, Smith HC, Holmes Jr DR, et al. Effect of dipyridamole and aspirin on late vein-graft patency after coronary bypass operations. New England Journal of Medicine 1984; 310:209–14.  Back to cited text no. 12
    
13.
Verstraete M, Brown BG, Chesebro JH, Ekeström S, Harker LA, Henderson AH, et al. Evaluation of antiplatelet agents in the prevention of aorto-coronary bypass occlusion. European Heart Journal 1986; 7:4–13.  Back to cited text no. 13
    
14.
Cosgrove DM, Loop FD, Lytle BW, Gill CC, Golding LA, Gibson CH, et al. Determinants of 10-year survival after primary myocardial revascularization. Annals of Surgery 1985; 202:480.  Back to cited text no. 14
    
15.
Grondin CM, Campeau L, Lespérance J, Enjalbert M, Bourassa MG. Comparison of late changes in internal mammary artery and saphenous vein grafts in two consecutive series of patients 10 years after operation. Circulation 1984; 70(3 Pt 2):I208-12.  Back to cited text no. 15
    
16.
Loop FD, Lytle BW, Cosgrove DM, Stewart RW, Goormastic M, Williams GW, et al. Influence of the internal-mammary-artery graft on 10-year survival and other cardiac events. New England Journal of Medicine 1986; 314:1-6.  Back to cited text no. 16
    
17.
Singh RN, Sosa JA, Green GE. Long-term fate of the internal mammary artery and saphenous vein grafts. The Journal of Thoracic and Cardiovascular Surgery 1983; 86:359-63.  Back to cited text no. 17
    
18.
Barbour DJ, Roberts WC. Additional evidence for relative resistance to atherosclerosis of the internal mammary artery compared to saphenous vein when used to increase myocardial blood supply. American Journal of Cardiology 1985; 56:488.  Back to cited text no. 18
    
19.
Sims FH. A comparison of coronary and internal mammary arteries and implications of the results in the etiology of arteriosclerosis. Ann Hear J 1983; 105:560.  Back to cited text no. 19
    
20.
Kay HR, Korns ME, Flemma RJ, Tector AJ, Lepley Jr D. Atherosclerosis of the internal mammary artery. The Annals of Thoracic Surgery 1976; 21:504-7.  Back to cited text no. 20
    
21.
Singh RN. Atherosclerosis of the internal mammary arteries. Cardiovasc Intervent Radiol 1983; 6:72.  Back to cited text no. 21
    
22.
Singh RN. Physiological nature of the internal mammary artery grafts. Cathet Cardiovascular Diagn 1985; 11:427.  Back to cited text no. 22
    
23.
Singh RN, Beg RA, Kay EB. Physiological adaptability: the secret of success of the internal mammary artery grafts. The Annals of Thoracic Surgery 1986; 41:247–50.  Back to cited text no. 23
    
24.
Landymore RW, Chapman DM. Anatomical studies to support the expanded use of the internal mammary artery graft for myocardial revascularization. The Annals of Thoracic Surgery 1987; 44:4–6.  Back to cited text no. 24
    
25.
Schmidt DH, Blau F, Hellman C, Grzelak L, Johnson WD. Isoproterenol-induced flow responses in mammary and vein bypass grafts. The Journal of Thoracic and Cardiovascular Surgery 1980; 80:319–26.  Back to cited text no. 25
    
26.
Chaikhouni A, Crawford FA, Kochel PJ, Olanoff LS, Halushka PV. Human internal mammary artery produces more prostacyclin than saphenous vein. The Journal of Thoracic and Cardiovascular Surgery 1986; 92:88–91.  Back to cited text no. 26
    
27.
Subramanian VA, Hernandez Y, Tack-Goldman K, Grabowski EF, Weksler BB. Prostacyclin production by internal mammary artery as a factor in coronary artery bypass grafts. Surgery 1986; 100:376–83.  Back to cited text no. 27
    
28.
Björk VO, Ivert T, Landou C. Angiographic changes in internal mammary artery and saphenous vein grafts, two weeks, one year and five years after coronary bypass surgery. Scandinavian Journal of Thoracic and Cardiovascular Surgery 1981; 15:23-30.  Back to cited text no. 28
    
29.
Tector AJ, Schmahl TM, Canino VR. The internal mammary artery graft: the best choice for bypass of the diseased left anterior descending coronary artery. Circulation 1983; 68(3 Pt 2):II214–7.  Back to cited text no. 29
    
30.
Tector AJ, Schmahl TM, Janson B, Kallies JR, Johnson G. The internal mammary artery graft: its longevity after coronary bypass. Jama 1981.  Back to cited text no. 30
    




 

Top
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
Abstract
Introduction
Materials and Me...
Results
Conclusion
References

 Article Access Statistics
    Viewed81    
    Printed1    
    Emailed0    
    PDF Downloaded10    
    Comments [Add]    

Recommend this journal