|
|
||||||||
J Thorac Cardiovasc Surg 2003;126:1968-1971
© 2003 The American Association for Thoracic Surgery
Surgery for acquired cardiovascular disease |
a Department of Cardiac Surgery, Catholic University, Rome, Italy
b Department of Angiology, Catholic University, Rome, Italy
Received for publication February 3, 2003; revisions received June 8, 2003; accepted for publication July 7, 2003.
* Address for reprints: Mario Gaudino, MD, Divisione di Cardiochirurgia, Policlinico Universitario A. Gemelli, Largo A. Gemelli 8, 00168 Rome, Italy
mgaudino{at}tiscalinet.it
| Abstract |
|---|
|
|
|---|
METHODS AND RESULTS: The intima-media thickness of the radial artery, common carotid artery, and internal thoracic artery was evaluated in 42 coronary artery disease patients and in 26 control patients. All radial arteries were then used for myocardial revascularization; 30 patients submitted to control angiography after 5 years. The mean intima-media thickness was 0.92 ± 0.22 mm for the common carotid artery, 0.54 ± 0.16 mm for the internal thoracic artery, 0.55 ± 0.11 mm for the radial artery in coronary artery disease patients versus 0.79 ± 0.14 mm, 0.52 ± 0.11 mm, and 0.56 ± 0.09 mm, respectively, in control patients (P = .001 only for the common carotid artery). No correlation was found between the intima-media thickness of the carotid, internal thoracic, and radial artery. No correlation was found between the preoperative intima-media thickness of the radial artery and the midterm patency and endothelial-mediated vasodilating capacity of radial artery grafts.
CONCLUSION: In coronary artery disease patients, radial artery atherosclerotic involvement is more frequent than that of the gold standard internal thoracic artery but still by far less severe than that of the common carotid artery. The early atherosclerotic signs often observed in the radial artery do not seem to have the potential to influence radial artery graft patency and endothelial function.
This prospective study was conceived to evaluate the degree of atherosclerotic involvement of the in situ RA and to verify the possible influence of eventual atherosclerotic lesions on the midterm patency of RA grafts.
For this purpose the intima-media thickness (a well known early marker of atherosclerosis) of the in situ RA was measured echographically in patients with CAD and in control patients, and the midterm angiographic results of the same RA used as coronary artery bypass grafts were evaluated in relation to the preoperative atherosclerotic involvement of the artery.
| Methods |
|---|
|
|
|---|
As part of the routine preoperative examination all patients underwent carotid echo-Doppler assessment following a previously described methodology6; carotid disease of any degree of severity was excluded.
The main clinical characteristics of the 2 cohorts of patients are summarized in Table 1. The 2 groups were comparable, although CAD patients had a superior prevalence of dyslipemia, diabetes, and previous myocardial infarction.
|
The diameter and intima-media thickness (IMT) of both common carotid arteries were evaluated 5 mm proximal to the bifurcation. ITAs were evaluated in the third intercostal space at the level of the parasternal line. Radial arteries were evaluated at the level of the interior third of the wrist (approximately 3 cm proximal to the crease of the wrist). All echographic measurements were performed at the selected points only in case of absence of disease; in case of presence of atherosclerosis or intimal thickening, measurements were performed in the most diseased segment.
The internal diameter of the vessels was evaluated using echographic image magnification and measuring the intima-intima distance in telediastole.
The IMT was measured in the far wall of the artery in telediastole (in concomitance with the R wave of the electrogardiogram), measuring the distance between the first echogenic border line (transition vascular lumen-intimal region) and the second echogenic border line (medial-advential region).
The use of the echo/ultrasound technique in evaluating the specific characteristics of the vascular wall, with particular regard to the ITA and the RA, has been described and validated by others.1-4
Surgical technique
As detailed elsewhere,5 decision about RA suitability for coronary artery bypass grafting is usually taken in the operating room during surgical harvesting; patients with moderate to severe atherosclerotic involvement or diffuse calcification are excluded. In this series the examined RAs were found to be free from significant atherosclerosis or calcification and were used a coronary artery bypass conduit for surgical myocardial revascularization in all CAD patients. Target RA vessels were the right coronary artery in 19 patients, the obtuse marginal branch in 14, and the diagonal in 9.
Angiographic follow-up
At a mean interval of 61 ± 7 months from surgery 30 of the 42 CAD patients submitted to angiographic control; none of the remaining patients died or had angina recurrence. During the procedure the RA response to endovascular acetylcholine infusion was also evaluated following a previously described method6 to assess midterm RA endothelial function.
Statistical analysis
Data are presented as mean ± standard deviation. Comparison between groups were performed by chi-square test for nonparametric data; for parametric data t test and Wilcoxon test were performed on the basis of their distribution. The correlation of variables was done using the Pearson coefficient. All analyses were done by using Intercooled Stata 6.0 for Windows (Statistics/Data Analysis, Stata Corporation, College Station, Tex). Statistical significance was established at P < .05.
| Results |
|---|
|
|
|---|
|
No difference in luminal diameter was found between the 2 groups for all examined arteries.
No correlation was found between the IMT of the CCA, ITA, and RA, although CAD patients showed a trend toward significance with regard to the correlation between the IMTs of the carotid and radial arteries (see Table 3).
|
|
|
|
| Discussion |
|---|
|
|
|---|
However, the RA has a peculiar histological and vasoactive profile,9,10 and only scant information is available on the degree of its atherosclerotic involvement in patients affected by CAD.
Different investigators have evaluated the histopathological aspects of distal samples of RA harvested from coronary artery bypass patients and reported evidence of initial atherosclerosis at least in some specimens10-12 (although these studies were limited by the fact that the authors analyzed only the segment of the vessel that remained after conduit utilization for coronary artery bypass graft).
Other investigators using ultrasound evaluation reported low overall incidence of overt atherosclerosis in the RA but found signs of early atherosclerotic involvement in a not negligible portion of patients1-3; however no direct comparison with other conduits was performed in these series, and the eventual influence of this early atherosclerosis on RA graft patency could not be established.
In the present series we preoperatively evaluated the echographic IMT of the CCAs, ITAs, and RAs in 42 patients with CAD and in 26 control patients and correlated the preoperative IMT with the midterm outcome of RA grafts. The IMT of the CCA was significantly higher in the study patients (reflecting the more severe atherosclerotic involvement in these patients) but the IMT of both the ITA and the RA was not influenced by the presence of coronary artery pathology (see Table 2). CAD patients showed a trend toward significance with regard to the correlation between the IMT of the carotid and radial (but not internal thoracic) arteries, testifying to the well-known intrinsic resistance to atherosclerosis of the gold standard conduit4 and, probably, an initial degree of pathology in the RA.
However, midterm angiographic control demonstrated that this early atherosclerosis had no effect on midterm RA graft patency and endothelial-mediated vasodilating capacity.
Although one could speculate that atherosclerosis does not have a significant effect on saphenous vein grafts until 5 years after coronary artery bypass and, thus, that it is conceivably possible that, similarly, disease will develop in the examined RA grafts only after the midterm angiography, we have demonstrated that all RA grafts that are perfectly patent 5 years after surgery remain perfect at 10 years (unpublished data) and the absolute lack of correlation between preoperative IMT and midterm RA angiographic status renders this hypothesis at least unlikely.
In addition, it must be acknowledged that due to the number of patients studied, a type II statistical error cannot be excluded with certainty. However, as significant P values were detected between some of the studied variables, the eventual undetected differences (if present) are extremely likely to be minimal and with limited clinical implications.
In conclusion it seems that in patients with surgical CAD the RA atherosclerotic involvement is more frequent than that of the gold standard ITA, but still by far less severe than of the CCA. In any case the early atherosclerotic signs often observed in the RA using subtle histopathological or echographic methods do not seem to have the potential to influence RA graft patency and endothelial function in the years after surgery.
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
N. S. Burris, E. N. Brown, M. Grant, Z. N. Kon, M. Gibber, J. Gu, K. Schwartz, S. Kallam, A. Joshi, R. Vitali, et al. Optical Coherence Tomography Imaging as a Quality Assurance Tool for Evaluating Endoscopic Harvest of the Radial Artery Ann. Thorac. Surg., April 1, 2008; 85(4): 1271 - 1277. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Onorati, F. Pezzo, M. C. Comi, B. Impiombato, A. Esposito, M. Polistina, and A. Renzulli Radial artery graft function is not affected by age. J. Thorac. Cardiovasc. Surg., November 1, 2007; 134(5): 1112 - 1120. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Wildhirt, B. Voss, F. von Canal, M. Benz, J. B. Grammer, R. Bauernschmitt, P. Tassani, and R. Lange Graft function, histopathology and morphometry of radial arteries used as conduits for myocardial revascularization in patients beyond age 70. Eur. J. Cardiothorac. Surg., August 1, 2006; 30(2): 333 - 340. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. G. Nezic, A. M. Knezevic, P. S. Milojevic, B. P. Dukanovic, M. D. Jovic, M. D. Borzanovic, and A. N. Neskovic The fate of the radial artery conduit in coronary artery bypass grafting surgery. Eur. J. Cardiothorac. Surg., August 1, 2006; 30(2): 341 - 346. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Zhang, T. Tazzeo, V. Chu, and L. J. Janssen Membrane potassium currents in human radial artery and their regulation by nitric oxide donor Cardiovasc Res, July 15, 2006; 71(2): 383 - 392. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Miwa, N. Desai, T. Koyama, E. Chan, E. A. Cohen, S. E. Fremes, and Radial Artery Patency Study Investigators Radial Artery Angiographic String Sign: Clinical Consequences and the Role of Pharmacologic Therapy Ann. Thorac. Surg., January 1, 2006; 81(1): 112 - 119. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Zhang, L. Janssen, and F. V. Chu Atherosclerosis of radial arterial graft may increase the potential of vessel spasm in coronary bypass surgery J. Thorac. Cardiovasc. Surg., November 1, 2005; 130(5): 1477 - 1478. [Full Text] [PDF] |
||||
![]() |
L. R. Sajja, G. Mannam, N. R. Pantula, and S. Sompalli Role of Radial Artery Graft in Coronary Artery Bypass Grafting Ann. Thorac. Surg., June 1, 2005; 79(6): 2180 - 2188. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Wildhirt INVITED COMMENTARY Ann. Thorac. Surg., November 1, 2004; 78(5): 1621 - 1622. [Full Text] [PDF] |
||||
![]() |
C. Chen-Scarabelli, T. Scarabelli, A. Zacharias, R. H. Habib, T. A. Schwann, C. J. Riordan, S. J. Durham, and A. Shah Factors Affecting Graft Patency: The Operating Room and Beyond * Response Circulation, August 10, 2004; 110(6): e64 - e64. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 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 |