Commentary on ‘Contrast Induced Nephropathy and Long-term Renal Decline After Percutaneous Transluminal Angioplasty for Symptomatic Peripheral Arterial Disease’

Abstract

Contrastinducednephropathy(CIN)asaresultoftheadministration of radiocontrast generally leads to reversible acute kidney injury. In patients with no risk, CIN is minor and insignificant (less than 1%). 1 In patients at risk(diabetes mellitus, chronic kidneydisease) the risk isup to 15%. 2 Other factorsthatcontributeto CINarepercutaneous coronary interventions with athero-embolization during catheter manipulation, hypovolemia, or advanced heart failure with reduced renal perfusion, but also contrast related factors (type, dose). In this issue of the European Journal of Vascular and Endovascular Surgery, Sigterman and colleagues 3 report 13% of CIN after endovascularprocedureforsymptomaticperipheralarterialdisease(PAD). They identified as risk factors, pre-operative anemia, critical limb ischemia, and low pre-intervention estimated glomerular filtration rate (eGFR). 3 These findings should be taken with caution. The prospective study included only patients with single radiocontrast use. Even a “homogenous” group does not represent the real world.The BASIL trial showed that 1.9e2.4 total number of endovascular interventions are necessary inpatientswith critical limb ischemia. 4 The authorsexcludedfromthecurrentstudypatientswithendstagerenal disease.What attracts attention to this paper isthe awareness of the existence of CIN in patients having endovascular treatment of PAD. The clinical implication of CIN awareness must result in the implementation of preventive measures (before, during, and after the intervention). It is obligatory to consider potentially nephrotoxic drugs and stop them: metformin, dipyridamole, NSAIDs, but also several ACE inhibitors and angiotensin II receptor blockers (Sartans). The use of potentially nephro-protective drugs such as antioxidants (N-acetylcysteine, ascorbic acid), or statins should be taken into account. 4 Considering the type of radiocontrast agent, clinicians must find a balance between the dose and the toxicity (isomolar and low osmolar contrast agents are less nephrotoxic) and the image quality. Insufficient image quality may require a second investigation, and results in radiocontrast accumulation. Adequate oral or intravenous hydration is essential. However, in the study hydration was used selectively only in patients with low eGFR.The benefit of decline in creatinine level and eGFR was to be expected also in patients with normal eGFR. Every vascular center should specify, according to international guidelines, their standard protocol to prevent CIN. One step forward might be a personalized endovascular intervention booklet, where the creatinine level and preventive measures can be documented in order to identify those patients with continuous decline of renal function. The use of alternative methods could eliminate or reduce radiocontrast during endovascular interventions. The value of intravascular ultrasound (IVUS) as a guide to treatment, and optimizing the length of the stent and its sizing is of no concern. In arteries with calcified, thrombotic lesions, the risk of distal embolization during the procedure is real, so that visualization of the foot and lower leg arteries is important. CO2 angiography is often “assisted” by initial or final single contrast use, and the image quality is worse than in conventional angiography. The overlay, 2D perfusion angiography, or wide range of 3D imaging tools, which are in use for complex aortic aneurysms, might be an option: translation to real life and PAD is on the waiting list. Patient specific rehearsal and pre-operative simulation might reduce radiocontrast use in complex aorto-iliac lesions, especially when a contralateral approach is used for the treatment iliac and femoral lesions; but there is a long way to go. 5 In the meantime, practitioners should not frighten patients by saying they will “lose their kidney” if they undergo any diagnostic/therapeutic radiocontrast intervention.They just have to use preventive measures to hamper renal function decline and to consider the possibility of applying alternative diagnostic/therapeutic methods.