Cardiovascular Journal of Africa: Vol 29 No 5 (September/October 2018)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 5, September/October 2018 278 AFRICA
Comparison of quantitative and qualitative coronary
angiography: computer versus the eye
Taner Sen, Celal Kilit, Mehmet Ali Astarcioglu, Lale Dinc Asarcikli, Tolga Aksu, Habibe Kafes, Afsin
Parspur, Gokhan Gozubuyuk, Basri Amasyali
Abstract
Objective: Since visual estimation of the extent of vessel
stenosis may vary between operators, we aimed in this study
to investigate both inter-observer variability and consistency
between the estimation of an operator and quantitative coro-
nary analysis (QCA) measurements.
Methods: A total of 147 elective percutaneous coronary inter-
vention patients with 155 lesions between them were consecu-
tively enrolled in the study. These patients were evaluated for
visual estimation of lesion severity by three operators. The
lesions were also evaluated with QCA by an operator who was
blinded to the visual assessments. Reference diameter, minimal
lumen diameter, percentage diameter of stenosis, percentage
area of stenosis and diameter of lesion length from the proxi-
mal lesion-free segment to the distal lesion-free segment were
calculated using a computerised QCA software program.
Results: There was a moderate degree of concordance in the
categories 70–89% (kappa: 0.406) and 90–99% (κ: 0.5813),
whereas in the categories < 50% and 50–69% there was a low
degree of concordance between the visual operators (κ: 0.323
and κ: 0.261, respectively). There was a low to moderate grade
of concordance between visual estimation and percentage
area of stenosis by QCA (κ: 0.30) but there was no concord-
ance between visual estimation and percentage diameter of
stenosis by QCA (κ: –0.061). Also, there was a statistically
significant difference between QCA parameters of percentage
diameter of stenosis and percentage area of stenosis (58.4 ±
14.5 vs 80.6 ± 11.2 %, p < 0.001).
Conclusion: Visual estimation may overestimate a coronary
lesion and may lead to unnecessary coronary intervention.
There was low concordance in the categories < 50% and
50–69% between the visual operators. Percentage area of
stenosis by QCA had a low to moderate grade of concordance
with visual estimation. Percentage area of stenosis by QCA
more closely reflected the visual estimation of lesion severity
than percentage diameter of stenosis.
Keywords: coronary stenosis, quantitative coronary analysis,
coronary angiography
Submitted 10/7/15, accepted 2/4/18
Cardiovasc J Afr 2018; 29: 278–282
DOI: 10.5830/CVJA-2018-024
Standard coronary angiography is the gold standard in the
diagnosis of coronary artery disease. Most laboratories use
visual estimation to predict the severity of coronary lesions.
Many patients undergo coronary revascularisation according
to visual estimation of their coronary stenosis. Unfortunately,
visual estimation may vary between operators.
In 1971, Gensini et al. first introduced a new electronic
measurement system by drawing the vessel contour with a
cursor.1 From the early 80s, many computer-based quantitative
coronary assessment (QCA) programs have been developed
and embedded in angiographic devices. Nowadays, modern
QCA programs enable more accurate assessment and more
reproducible measurement of coronary stenosis in an operator-
independent way.
Many studies have shown inter-operator variation and
discrepancy between visual estimation and QCA analysis. Most
of these studies were performed before 2000.2-8 In a recent study
performed by Nallamothu et al., the authors found that many
operators tend to estimate coronary lesions more severely than
QCA measurement. 9 This is consistent with older studies. In the
light of this study, many patients who did not have severe lesions
according to QCA have undergone unnecessary revascularisation
procedures based on visual estimation.
In this retrospective study, we aimed to investigate both
inter-observer variability and consistency between the visual
estimation of a primary operator and QCA measurement in a
blinded manner in patients who had had elective percutaneous
coronary intervention (PCI) in our clinic.
Methods
A total of 147 consecutive patients who had had elective PCI
between January and June 2015 were enrolled in the study.
Department of Cardiology, Dumlupinar University,
Kutahya Evliya Celebi Education and Research Hospital,
Dumlupinar, Turkey
Taner Sen, MD,
Celal Kilit, MD
Mehmet Ali Astarcioglu, MD
Afsin Parspur, MD
Basri Amasyali, MD
Department of Cardiology, Dıskapi Yildirim Beyazit
Education and Research Hospital, Ankara, Turkey
Lale Dinc Asarcikli, MD
Department of Cardiology, Derince Education and
Research Hospital, Derince, Turkey
Tolga Aksu, MD
Department of Cardiology, Yuksek Ihtisas Hospital, Ankara,
Turkey
Habibe Kafes, MD
Department of Cardiology, Malatya State Hospital, Malatya,
Turkey
Gokhan Gozubuyuk, MD