Prevention of contrast induced nephropathy; a cardiology point of view

By increasing the number of cardiovascular procedures, iodinated contrast media (ICM) is one of the most common agents used for diagnostic and prognostic and also therapeutic cardiac interventions. Contrast induced nephropathy (CIN) is one of the most leading causes of hospital-acquired renal insufficiency (1). Following cardiovascular invasive procedures, CIN occurs in about 3.1 to 31% of patients (2). CIN induces unfavorable outcomes and is associated with increased morbidity and mortality rate in hospitalized patients (3). This is a multifactorial disease, however, various pathophysiologic mechanisms have been attributed to development of CIN such as; direct toxicity to tubular cells, renal ischemia and hypoperfusion, oxidative stress, direct pro-apoptotic effects, altered vasomotor balance, enhanced vasoconstriction due to increased adenosine, endothelin, free radicals and decreased vasodilation due to diminished nitric oxide and prostaglandin levels (Figure 1) (4). Consequently, decreased renal perfusion and medullary ischemia contribute to the development and progression of CIN, but the real cause is still unknown (5,6). Hereby, we are going to introduce a memorial name for better identification of at risk patients derived from the risk factors with strongest odd’s ratio. In a survey of full-text searches of electronic databases we have collected risk factors for CIN. Among them, the most common reported risk factors were focused. This would not be a scoring system but this acronym introduce an easy memorial name in order to estimate risk factors of CIN in cases undergoing coronary angiography and intervention to prevent occurrence of CIN. Since the most commonly reported risk factors related to the occurrence of CIN were hypotension/hypertension/ heart failure/hemodynamic instability, diabetes mellitus (DM), renal insufficiency, agents as antihypertensive drugs, antibiotics, non-steroidal anti-inflammatory drugs/ anemia, total contrast volume and type, elderly, female gender; the memorial word could be hydrate-her (7-11). Hereby, we introduce a memorial prediction system based on the predisposing risk factors with strongest odds ratio for development of CIN. Regarding hydrateher, a brief explanation is provided in the following section. Hemodynamic instability extremely predisposes patients to the development of CIN as in the case of intraaortic balloon use and sepsis (7,12). Pre-existing renal insufficiency has been defined as creatinine level of >1.2 mg/dl (13). Indeed, patients with glomerular filtration rate (GFR) level below 30 ml/min, 30-60 ml/min and >60 ml/ 1Departmentof Cardiology, Isfahan University of Medical Sciences, Isfahan, Iran 2Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran 3Isfahan Heart Failure Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran