The main finding of our study is that a history of
CRF, excess contrast material used, low LVEF, and
high plasma glucose level are predictive of contrast
nephropathy in patients with CCS who underwent
PCI for CTO. It has been shown in previous
studies that the most important predisposing factor
in the development of contrast nephropathy is the
presence of underlying CRF. Persistence of damage
to kidney function after contrast nephropathy has
been associated with the degree of CRF. Even if
hemodialysis is not needed most of the time, contrast
can cause permanent damage in 30% of patients
affected by nephropathy.[
8-
11] In a retrospective study
by Lewy et al.,[
12] mortality and length of hospital stay
were found to be significantly higher when the group
that developed contrast nephropathy was compared
to the control group, and this result was found due
to the findings of acute kidney failure. Again, in
the long-term follow-up results of Guzel et al.[
13]
in patients with CTO, mortality was higher in the
group with contrast nephropathy after PCI. The most
important measure to avoid contrast nephropathy is
to use the least amount of contrast material possible.
In previous meta-analyses, the increase in the amount
of contrast material used and the use of opaque
materials with high osmolarity increased the risk of
nephrotoxicity.[
14,
15]
In previous studies, intravenous fluid
administration at least 2 h before and after the
procedure to patients with subclinical dehydration
before contrast administration has been shown to reduce contrast nephropathy.[16,17] Based on this data,
we can conclude that the higher blood osmolarity of
patients with higher fasting plasma glucose may lead
to contrast nephropathy. In addition, hyperglycemia
itself can increase oxidative stress as a result of free
oxygen radicals, resulting in both adverse effects on
the pathophysiology of DM and damage to the renal
tubular system.[18]
Shacham et al.[19] investigated the effect of left
ventricular systolic function on acute kidney injury in
patients with acute myocardial infarction (AMI) and
showed that the prognosis is poor in older patients with
impaired renal function and low LVEF. Wang et al.[20]
found a higher risk of developing contrast nephropathy
in patients with low ejection fraction in their study of
the relationship between contrast nephropathy and
LVEF after CAG in patients with heart failure. In our
study, LVEF was found to be lower in the group with
contrast nephropathy.
The main limitations of the study were that it was
a single-center study and retrospective in design. In
addition, data on hemodynamic variability during
the angiography procedure, whether patients were
hydrated with intravenous fluid before the procedure,
and long-term follow-up results were lacking.
In conclusion, a high creatinine value at baseline
(underlying CRF), high blood sugar that increases
plasma osmolarity (uncontrolled DM), high amount
of contrast agent used, and low LVEF are predictors
of contrast nephropathy in patients with CCS who
underwent PCI for CTO. Paying attention to the risk
factors that can be corrected before the administration of contrast material to patients is valuable to reduce
renal damage.
Ethics Committee Approval: The study protocol was
approved by the Bakırçay University Non-Invasive Clinical
Ethics Committee (date: 08.03.2023, no: 2023/905). The
study was conducted in accordance with the principles of the
Declaration of Helsinki.
Patient Consent for Publication: Written informed
consent was not obtained as this study was retrospective.
Data Sharing Statement: The data that support the
findings of this study are available from the corresponding
author upon reasonable request.
Author Contributions: Collected study data, wrote the
main manuscript, and prepared the tables: F.S.Y.; Performed
statistical analyses the article: A.A.B.; Reviewed the article:
Y.D., E.O.B.; All authors have read and approved the final
article.
Conflict of Interest: The authors declared no conflicts
of interest with respect to the authorship and/or publication
of this article.
Funding: The authors received no financial support for
the research and/or authorship of this article.