Early Diagnosis as a Strategy in Reducing the Incidence of Acute Renal Failure and Mortality Associated With Contrast Media Administration in Cardiovascular Procedures

Kidney damage is one of the most frequent complications of cardiac intervention. This pathology is called contrast-induced nephropathy (CIN) and is defined as an increase in plasma creatinine greater than or equal to 0.5 mg/dL, or greater than or equal to 25% with respect to baseline, during the 5 days after contrast medium (CM) administration.

The appearance of acute renal damage significantly increases the health costs associated with interventional procedures. This is derived from the increase in the length of hospital stay, in care units, and from the application of dialysis as the only existing treatment. In the United States, it has been estimated that the development of acute in-hospital renal damage increases health expenditure by $ 7933 per patient per day, mainly due to the increase in hospitalization time. Thus, not only the very early detection, but especially the prevention of acute renal damage are key aspects for the prognosis of the patients, and for the control of the health expenditure associated with them.

Iodized CMs are the leading cause of acute renal damage of toxic origin in humans. CMs produce renal ischemia derived from a vasoconstriction that has two effects: on the one hand reduction of glomerular filtration, and on the other, tubular ischemic damage that amplifies the reduction of filtrate and, with it, renal dysfunction.

Different scales have been proposed to determine the risk of developing CIN, which include different variables such as the presence of arterial hypotension, the use of counterpulsation balloon, the age over 75 years, the presence of anaemia, diabetes, the amount of CM used and renal function. Each item is assigned a certain score in the case of being present in the patient and depending on the final score, the possible risk of contrast nephropathy after the procedure and even the risk of dialysis is estimated. However, these scales are not widely used in clinical practice and their usefulness is doubtful.

Currently the detection of renal damage associated with CM is performed using the plasma creatinine marker. The main drawback of this detection mode is that creatinine levels increase when renal functionality is already altered. In other words, detection occurs when renal functionality has decreased by approximately 70%. This is why new markers capable of detecting damage in their earliest stages are currently being evaluated, when the damage is less widespread. Also in the last decade a new concept of biomarker called a marker of predisposition to kidney damage has emerged. This concept has been revealed after verifying that certain treatments significantly increase the risk of suffering an acute renal failure, and do so in a hidden and silent way.