title: Histopathology and morphometry of radial artery conduits: basic study and clinical application.
abstract: BACKGROUND
  The purpose of this study was to determine the pathohistology, morphometry, and risk factors for the development of intimal hyperplasia, calcification, and arteriosclerosis in the radial artery and to compare the morphometry of the distal and proximal radial arteries.
  
  
  METHODS
  A total of 190 proximal and distal radial artery specimens obtained from patients who underwent myocardial revascularization were exposed to histopathologic and morphometric analysis. The severity of disease was evaluated on the basis of the percentage of luminal narrowing, intimal thickness index, and intima-to-media ratio.
  
  
  RESULTS
  Sixty-two proximal (32.6%) and 22 distal (11.5%) radial artery segments were indicated as histologically normal. Morphometric analysis (Z test) revealed a lesser degree of intimal hyperplasia and luminal narrowing in the proximal segments compared with the distal segments (p < 0.001). The incidence of intimal hyperplasia, medial calcification, and arteriosclerosis in the distal radial arteries was 76.3%, 6.3%, and 5.78%, respectively. Using multivariate logistic regression, we have identified three significant predictors for intimal hyperplasia. Expressed as an odds ratio with a 95% confidence interval, these included (i) age greater than 50 years (1.052; 1.000-1.106, p = 0.052), (ii) smoking (14.073; 5.293-37.414, p = 0.000), and (iii) hypertension (2.777; 1.171-6.583, p = 0.020). Factors associated with an increased likelihood of medial calcification and arteriosclerosis included a history of smoking, diabetes, hypercholesterolemia, peripheral arterial disease, and chronic renal failure (p < 0.05).
  
  
  CONCLUSIONS
  The great majority of radial artery conduits indicate preexisting intimal hyperplasia mostly affecting the distal portion. Therefore in cases of longer diseased segments of radial arteries, the discarded segments should be the distal end. Care should be taken when selecting radial artery as a conduit in myocardial revascularization, particularly in elderly males, diabetics, smokers, hypertensive patients, and in those with associated peripheral vascular disease.
authors.affiliation: Department of Cardiothoracic, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India. ujjwalchow@rediffmail.com
authors.forename: Ujjwal K
authors.initials: UK
authors.lastname: Chowdhury
authors.forename: Balram
authors.initials: B
authors.lastname: Airan
authors.forename: Pankaj K
authors.initials: PK
authors.lastname: Mishra
authors.forename: Shyam S
authors.initials: SS
authors.lastname: Kothari
authors.forename: Ganapathy K
authors.initials: GK
authors.lastname: Subramaniam
authors.forename: Ruma
authors.initials: R
authors.lastname: Ray
authors.forename: Rajvir
authors.initials: R
authors.lastname: Singh
authors.forename: Panangipalli
authors.initials: P
authors.lastname: Venugopal
mesh_terms: D000328:Adult; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000453:epidemiology / Q000473:pathology*; D001161:Arteriosclerosis / Q000453:epidemiology / Q000473:pathology; D002114:Calcinosis / Q000473:pathology; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007194:India / Q000453:epidemiology; D007676:Kidney Failure, Chronic / Q000453:epidemiology; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D017534:Radial Artery / Q000473:pathology* / Q000637:transplantation; D012307:Risk Factors; D020858:Tissue and Organ Harvesting; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology; D014654:Vascular Patency