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Intravenous iodinated contrast media are commonly used in clinical practice, ranging from medical imaging to interventional radiology (IR) procedures and endovascular interventions. Compared with patients with normal renal function, nephropathic patients have an increased risk of acute kidney injury (AKI). Nevertheless, this condition cannot represent a limit to diagnostics or endovascular interventions. Despite the literature of the last five years, conflicting management and approaches for nephropathic patients persist, including the use of contrast agents and treatments replacing renal functions, which are often mistakenly considered as part of preventive strategies. Though the issue has been widely discussed, specialists often cope with uncertainty in handling properly the administration of contrast media and renal counselling requests. Furthermore, there is a general difficulty in distinguishing the Post-Contrast Acute Kidney Injury (PC-AKI) from the Contrast-Associated Acute Kidney Injury (CI-AKI). The present review aims to provide an update on the issue and examine strategies to reduce the acute kidney injury risk after the administration of contrast media. These strategies include the early identification of high-risk individuals, the choice of the contrast media and the proper dosage, the suspension of nephrotoxic drugs, the follow-up of the high-risk individuals, and the early identification of AKI., (Copyright by Società Italiana di Nefrologia SIN, Rome,Italy.)

The use of organo-iodinated contrast media (CM) in diagnostics and intervention has increased in the last 10 years. It is necessary to distinguish between the different types of contrast agent, primarily with respect to osmolarity: with low osmolarity the safety profile for the patient is higher. The risk of acute renal injury caused by contrast agent (PC-AKI) is however determined also by risk factors related to the patient. Particularly in main centers, it is advisable to have a standardized program in order to stratify patients with respect to risk, to define prevention strategies and the roles of the specialists involved. The experience described in this work consists in the application of an organizational model relating to CT, with a feasibility study of applying an evidence-based check-list in the clinical routine, as a tool to support clinical decisions (Clinical Decision Support System, CDSS) in the oncology field. A pilot evaluation was carried out on 54 patients belonging to the case series treated in a Teaching Hospital, in a day service regime with a diagnosis of solid tumor. The results of this evaluation led the working group to believe that the CDSS thus structured determines the possibility of overestimating the clinical risk of PC-AKI, and consequently to redefine the evaluation form. Experience has shown that it is not generally easy to immediately identify an algorithm useful for standardizing the management of clinically complex situations, such as PC-AKI prevention. The conduction of pilot evaluations can be a valid instrument of harmonization between the solidity of the references deriving from evidence based medicine and the tangibility of real world data. It is advisable to broaden the application of the CDSS more in a larger number of cases, as well as conduct a pre-post analysis relating to the clinical impact in terms of incidence from PC-AKI.

Contrast-induced acute kidney injury (CI-AKI) consists in acute decline in renal function following iodinated contrast media exposure. It has a significant impact on long-term prognosis and mortality, development of chronic kidney disease and on the rate of hospitalization due to cardiovascular or renal events. Anamnestic and procedural aspects linked to higher risk of CI-AKI have been investigated and new devices have been designed in order to prevent it. This paper deals with CI-AKI in interventional cardiology, focusing on patients' risk stratification, contrast media agent selection and contrast media volume reduction strategies, in order to suggest a standardized algorithm.

Iodinated contrast-induced nephropathy is one of the most feared complications of percutaneous coronary interventions and is associated with increased cardio-vascular mortality and a faster progression towards end stage renal disease. The effects of the iodinated contrast medium on intra-renal hemodynamics and its direct cytotoxic action on proximal tubular cells contribute synergistically to the pathophysiology of renal damage. Since the therapeutic options are extremely limited, the rapid identification of risk factors and the timely implementation of preventive strategies are mandatory to reduce the incidence of iodinated contrast-induced nephropathy. To date, the criteria for defining and staging contrast medium nephropathy are still based on the increase of serum creatinine and/or contraction of diuresis, which are lacking in specificity and therefore do not allow early diagnosis. The aim of this review is to report the latest evidence on the pathophysiological mechanisms that contribute to renal damage by iodinated contrast medium, on the risk stratification tools and on the new early biomarkers of contrast-induced nephropathy, while also focusing on the most validated prevention strategies., (Copyright by Società Italiana di Nefrologia SIN, Rome, Italy.)

Contrast-induced acute kidney injury (CI-AKI) is a serious complication that can affect outcome and prognosis of patients undergoing percutaneous diagnostic and interventional procedures. The Italian Society of Interventional Cardiology (SICI-GISE) has promoted a consensus project on the subject of CI-AKI in order to disseminate and implement nephroprotection strategies in interventional cardiology. The initiative was conducted in partnership with the Italian Society of Nephrology (SIN).

The management of patients with severe coronary artery disease and severely impaired renal function may be challenging. In this report, we describe the case of a 75-year-old patient who underwent complex percutaneous coronary intervention with an ultra-low dose contrast medium protocol. Notably, the patient was scheduled for the procedure after careful monitoring of fluid expansion as assessed by echocardiography. No contrast-induced nephropathy developed and the patient was discharged safely.

Background: Sialadenitis by iodinated contrast medium (i.c.m) oriodine mumps (IM) is a rare and late benign manifestation that occurs independently of intravenous or endoarterial administration modality. If renal function is normal, i.c.m. does not reach salivary glands concentrations able to induce sialadenitis. However, a critical glomerular filtration reduction may lead to salivary ducts edema and glandular swelling after i.c.m. injection. We report a rare case report of IM in a patient on chronic hemodialysis., Methods: A 72-year-old woman affected by chronic kidney disease on chronic hemodialysis, underwent to endoscopic removal of a rectal cancer. For disease staging, a total body TC with i.c.m. was performed. The following morning, patient showed a soft and aching bilateral paroditidis swelling. Salivary glands ultrasound was diagnostic for sialadenitis. The patient was rapidly treated with betamethasone following by a 240 minutes post-dilution online hemodiafiltration session., Results: Within the next 24h, a complete remission of IM was obtained., Conclusion: In our patient, a compensatory hyperactivity of the sodium / iodine symporter (NIS) on salivary gland cells may have played a crucial role in IM induction. An high efficiency hemodialysis session within the few following hours after i.c.m injection is a fundamental tool in patients on renal replacement treatment to prevent IM that is an epiphenomenon of i.c.m. accumulation., (Copyright by Società Italiana di Nefrologia SIN, Rome, Italy.)

Successful percutaneous coronary intervention of chronic total occlusions (CTO) is associated with favorable clinical outcomes in selected subsets of patients. The success rate of CTO interventions greatly increased over the last decades, thanks to the development of dedicated materials and interventional strategies. Nevertheless, CTO interventions are still challenging with higher complication rates and lower success rates compared to standard percutaneous coronary interventions. Dedicated CTO operators are warranted in order to minimize the rate of complications and to achieve a success rate near to 90%. This state of the art paper is aimed to provide updated evidences on the clinical benefit of CTO recanalization and to describe specific interventional techniques for CTO recanalization.

The intravascular administration of contrast media is an important tool in cardiovascular imaging, especially in percutaneous coronary interventions (PCI). Owing to the widespread use of these procedures, contrast-induced acute kidney injury (CI-AKI) has become one of the most common types of acute renal failures. CI-AKI is mainly mediated by mechanisms of oxidative damage, and its onset is associated with prolonged hospitalization and significant morbidity and mortality. Preexisting chronic kidney disease, diabetes, age, heart failure, and characteristics related to the procedure (primary or elective PCI, type and amount of contrast medium) are the most important risk factors for the development of post-PCI CI-AKI.For this serious complication, prevention is more important than treatment, and various preventive measures have been widely tested in recent years. However, none of the strategies so far evaluated, with the exception of pre-procedural hydration with isotonic saline, has been shown to effectively prevent CI-AKI in randomized trials in large populations. In this review, we discuss the incidence, risk factors, main pathogenetic mechanisms and current strategies for the prevention of CI-AKI.

Iodinated radiographic contrast media may cause kidney dysfunction that occurs in particular in patients with pre-existing renal impairment and/or diabetes. This impairment of renal function is called contrast-induced nephropathy (CIN), i.e. an acute renal failure occurring within 24-72 hours after the intravascular injection of iodinated radiographic contrast media that cannot be attributed to other causes. The pathogenesis of CIN has not been fully elucidated yet. It may be due to several factors, including renal ischaemia, particularly in the renal medulla, formation of reactive oxygen species (ROS), reduction of nitric oxide (NO) production, tubular epithelial and vascular endothelial injury. CIN can be prevented. For prevention, however, we need to know the risk factors. I have reviewed the pathogenesis and the risk factors for CIN and discussed the measures for its prevention, providing a long list of references which will allow readers to evaluate deeply this iatrogenic disease.

Contrast-induced nephropathy has become a significant source of hospital morbidity and mortality particularly in patients with multi-organs defects. No current treatment can reverse or ameliorate contrast induced nephropathy once it occurs, but prophylaxis is possible. We present the case of a 61-year-old male patient with concomitant chronic kidney disease (CKD stage III K/DOQI) and diabetes complicated by severe multi-vascular disease, who developed acute kidney damage probably due to the simultaneously exposure to intravascular contrast media and cholesterol crystal embolism. In addition, owing to rapid deterioration of renal function, this patient started renal replacement therapy. No renal biopsy was performed due to the poor clinical condition of the patient. After a month of hemodialysis, he switched to a peritoneal dialysis procedure to which specific treatment for vascular lesions, including antibiotics, prostanoids, hyperbaric oxygen therapy, antiaggregants/anticoagulants and physiotherapy, was associated. After 7 months, the dialysis treatment was stopped and he began intensive clinical follow-up. At present, the patient is in conservative medical treatment (the Tenckhoff catheter has been removed), he is in good condition and severe vascular lesions are absent. Our conclusion is that contrast-induced nephropathy in vasculopathic diabetic patients requires a multidisciplinary approach. In particular, good cooperation between nephrologists and angiologists is useful to avoid rapid and chronic deterioration of renal failure and to prevent the onset and development of severe vascular damage.

Sialadenitis (Iodide Mumps) is a rare complication following the administration of iodinated contrast media. It is characterized by the painless bilateral enlargement of the submandibular salivary glands. The pathogenesis of this adverse reaction remains unclear. It may be due to an idiosyncratic reaction or related to toxic accumulation of iodide in the ductal systems of the salivary glands. Iodide mumps may occur after administration of any iodinated contrast agent: 98% of injected iodide is eliminated by the kidneys and only 2% is excreted from other organs such as salivary, sweat and lacrimal glands. Normally, the injected dose of contrast medium does not provide a sufficiently high iodide concentration to cause iodide mumps, but impaired renal excretion of contrast medium results in liberation of iodide and enables the salivary glands to concentrate inorganic iodide. This condition is rare and self-limiting. The current management is supportive therapy using analgesics and dialysis. We report two cases of iodide mumps in end-stage renal disease (ESRD) patients treated with haemodialysis after administration of iodinated contrast media. The cases were characterized by rapid onset and resolution of the symptoms in the absence of specific treatment.

Contrast-induced nephropathy (CIN) is one of the most frequent causes of acute kidney injury in hospitalized patients. Its incidence depends on patient risk factors (chronic kidney disease, diabetes, cardiovascular diseases and older age) and procedure-related factors (high contrast dose, intraarterial administration). Chronic kidney disease, especially if associated with diabetes, is the main risk factor for CIN. Hydration before and after contrast administration is the only preventive therapy that is strongly recommended by guidelines in patients at risk. CIN prevention studies have focused mainly on cardiac patients with a moderate renal risk (GFR 60-40 mL/min) who underwent intraarterial contrast administration. Many clinical trials have evaluated the efficacy of hydration associated with sodium bicarbonate and of N-acetylcysteine (NAC) in CIN prevention. Sodium bicarbonate infusion has shown better efficacy than saline infusion, particularly when short infusion times are needed, such as in emergency procedures. NAC has not shown any clear effect, and some positive study results have not been confirmed in other trials. The discussion is still open on the efficacy of renal replacement therapies for the prevention of CIN in individuals at high renal risk (GFR <30 mL/min), in whom CIN could mark the entrance to chronic dialysis.

Contrast-induced nephropathy (CIN) has undergone a significant evolution over the years in terms of epidemiology and diagnostic criteria. At present it is defined as CI-AKI (contrast-induced acute kidney injury) and represents a pathologically relevant event for different disciplines. Thus, a multidisciplinary approach is needed to propose and deploy a common strategy to reduce the incidence of CI-AKI. It seems that the use of isoosmolar non-ionic contrast media such as iodixanol can reduce the nephrotoxic effects. However, since these - still controversial - results have been obtained using various diagnostic criteria, they are difficult to compare and pool together. Common criteria are therefore required. The term acute renal failure has been replaced by acute kidney injury (AKI). Thanks to consensus groups such as ADQI (Acute Dialysis Quality Initiative) and AKIN (Acute Kidney Injury Network) and the development of guidelines by KDIGO, the diagnostic criteria for AKI are well defined. Nevertheless, the possibility to utilize new biomarkers of structural kidney damage such as neutrophil gelatinase-associated lipocalin (NGAL) or cystatin C has introduced the concept that AKI may be diagnosed even in the absence of creatinine elevation or decreased urine output. A re-evaluation of the epidemiology of CI-AKI based on new diagnostic criteria is required. In this paper the results of a collaborative multidisciplinary study group are reported from the perspective of different disciplines including nephrology, cardiology, radiology and pharmacology. The findings in a cohort of cardiac patients undergoing imaging procedures using exclusively the isoosmolar non-ionic contrast medium iodixanol are evaluated according to the RIFLE/AKIN criteria.

We review the current approach to using gadoliniumbased contrast agents taking into account data published in the literature and US Food and Drug Administration and European Medicines Evaluation Agency (EMEA) guidelines.

Lipid lowering therapy with statins reduces the risk of cardiovascular events in patients with coronary artery disease. Recent in vitro and in vivo studies demonstrated LDL-independent action of this class of drugs, which appears in modulating endothelial function, inflammation and thrombosis. Periprocedural myocardial infarction and contrast induced nephropathy after percutaneous coronary intervention (PCI), associated with worse outcome on short and long term follow-up, are both complications related to inflammatory pathogenetic mechanisms. Randomized studies showed a beneficial effect of short-term statin pretreatment in reducing peri-procedural cardiac markers release in patients undergoing PCI. In fact, statin therapy before elective PCI reduced periprocedural myocardial infarction in patients with stable angina. Furthermore, an acute loading with high-dose atorvastatin prevented myocardial damage in patients with acute coronary syndromes undergoing early PCI (<48 hours). In patients already on chronic statin therapy, a reload with high dose statin was associated with a significant improvement on 30-day cardiac outcome. Finally, statin therapy at the time of PCI significantly decreased the incidence of contrast-induced nephropathy. All these evidences support an "upstream administration" of short-term, high-dose statins in all patients undergoing PCI, in order to achieve pleiotropic, LDL-independent effects of these drugs.

Unlabelled: This paper analyses off-label prescribing of the iodinated organic and magnetic resonance (MR) contrast media used in diagnostic imaging and evaluates the liability profiles and medicolegal issues associated with such use. The term off-label generally indicates the use of known drugs for which new scientific evidence suggests use in a manner and in clinical scenarios not explicitly addressed by the drug data sheet and is outside the indications for which the medication was approved. In addition, the term also indicates the use of drugs with a different route of administration and dosage from those indicated in the information leaflet. Intravascular contrast media used in diagnostic imaging are drugs in the complete sense of the term, even though they have unique characteristics which in many ways distinguish them from other pharmacological agents. The off-label use of contrast media in diagnostic imaging is a little-investigated field and most commonly, but not exclusively, applies to gadolinium-based contrast media used in MR angiography as well as cardiac and paediatric applications. In particular, the off-label use of contrast media mostly concerns deviations from the recommended dose. As contrast media are to all effects pharmaceutical agents, their off-label use can be considered admissible within the limitations laid down by the Italian law in force (Article 3 of Law 94/98) and its interpretation, i.e. the following criteria must be present: the lack of a valid diagnostic alternative; written informed consent by the patient; the presence of scientific publications validated at the international level; assumption of responsibility by the radiologist., Conclusions: The use of contrast media in modern image-guided medicine is essential. In cases in which the information contained in the information leaflet is modified and updated in any way whatsoever (indications, dosage, at others), specifically if restrictions are introduced in accordance with the law in force, the pharmaceutical industry must provide formal and timely notification to radiologists. On their part as prescribers and users of contrast media, radiologists must remain up to date regarding any changes in indications, dosage and route of administration. Lastly, we propose that the radiology report includes not only the type but also the dose of contrast medium used.

Treatment of ST-elevation myocardial infarction has advanced tremendously over the past years; this development has proven to be beneficial in reducing mortality and cardiovascular events. Clinical baseline factors remain the cornerstone of prognostic stratification. Tools for prognostic stratification after myocardial infarction are targeted at evaluating myocardial damage, left ventricular dysfunction, residual ischemia and electrical instability. Primary coronary angioplasty is the preferred therapeutic option because, when it can be performed expeditiously by an experienced team, has shown better clinical outcomes; nevertheless we have to pay attention to avoid procedure-related risks such as bleeding and contrast-induced nephropathy.

The utilization of renal replacement therapies in cardiac patients has received increasing attention in recent years. In fact, isolated ultrafiltration has been proposed in patients with heart failure as a means for rapidly relieving fluid overload while preserving renal function; moreover, periprocedural hemofiltration (HF) has been suggested for radiocontrast-induced nephropathy (RCIN) prophylaxis. As a matter of fact fluid overload, with the ensuing systemic and pulmonary congestion, remains a major problem in patients with heart failure, and diuretic resistance is not an uncommon feature in the more advanced stages of the syndrome. In the same way, RCIN is increasingly indicated as a major complication of the use of iodinated contrast media, accounting for a significant number of hospital-acquired acute kidney injury episodes; moreover, it is thought to be associated with short- and long-term adverse effects on patient prognosis and increased economic burden. This article is aimed at reviewing the background of renal replacement therapies in the clinical context of cardiology wards, with special regard to isolated ultrafiltration and HF, as well as the current evidence regarding the safety and efficacy of these procedures, and their economic impact. From a theoretical point of view, isolated ultrafiltration could have a number of potential heart- and kidney-related advantages if compared to standard therapy (mainly diuretics). However, currently available clinical evidence does not support these concepts for its widespread utilization. Thus, isolated ultrafiltration should be reserved for selected patients with advanced heart failure and diuretic resistance, as part of a more complex strategy devoted to the control of fluid retention. There is currently no sound evidence for routinely recommending periprocedural HF in coronary angiography procedures, even in patients at high risk for RCIN.

Purpose: The aim of this paper is to report on the implementation of new guidelines on the use of injectable iodinated contrast media (ICM) at our workplace and specific protocols for the preparation of patients at risk., Materials and Methods: Operators received training with continuing medical education (CME) credits. The new documentation (patient history/screening form and informed consent form) is available on the hospital Web site and requests serum creatinine determination with estimation of glomerular filtration rate (GFR) for every patient. Additional tests are required for high-risk patients only., Results: Attendance rates were 57.2% among referring physicians and 74.5% among Radiology Department personnel. The Cockcroft-Gault formula was used to estimate GFR in adults. The main problem encountered in the implementation process was that referring physicians failed to evaluate the GFR in 80% of patients, with low GFR being discovered in the Radiology Department on the day of examination in 20% of patients, resulting in a need to reschedule the examination., Conclusions: Although not an easy task, implementation of the new guidelines for ICM use is both feasible and necessary. An additional refresher training course for personnel and GFR evaluation of the patient on referral are indispensable to ensure proper preparation of patients at increased risk of adverse reactions to ICM.

Radiological procedures that utilize intravascular iodinated contrast media are being widely applied for both diagnostic and therapeutic purposes and represent one of the main causes of contrast-induced nephropathy (CIN) and hospital-acquired renal failure. Owing to the lack of any effective treatment, prevention of this iatrogenic disease, which is associated with significant in-hospital and long-term morbidity and mortality and increased costs, is the key strategy. However, prevention of CIN continues to elude clinicians and is a main concern during percutaneous coronary interventions, as patients undergoing these procedures often have multiple comorbidities. The purpose of this article is to examine the risk factors and clinical course of CIN, as well as the most recent studies dealing with its prevention and potential therapeutic interventions, especially during percutaneous coronary interventions.

Contrast-induced nephropathy is one of the major causes of kidney failure in hospitalized patients. Its increased frequency is due to the high number of invasive procedures using contrast media performed for diagnostic or therapeutic purposes in patients with cardiovascular diseases with advanced age and chronic comorbidities such as diabetes and preexisting renal failure. There are two main causes of contrast-induced nephropathy: the direct toxic effect of contrast media on kidney tubules (as shown by morphologic alterations of these cells) and the tissue hypoxia of the renal medulla, secondary to the hemodynamic effects brought about by these agents, consisting in a reduction of vascular resistances. In vulnerable patients, these vasoconstrictor effects are not balanced by an effective vasodilatory reserve and probably by a reduced production of antiapoptotic proteins.

Chronic kidney disease affects large numbers of individuals in countries across the world. Recent reports from the United States indicate that 30% of the adult population has a mild or moderate degree of chronic renal failure and more than 600,000 patients are projected to have end-stage renal disease by the year 2010. Similar elevated rates have been reported in Europe, Asia and Australia. Optimal management of chronic renal failure is mandatory. It requires a correct diagnosis of the underlying nephropathy and specific strategies to slow the progression of renal damage and to prevent cardiovascular events. The differential diagnostic approach to chronic renal failure consists of serologic studies, renal biopsy, and urinary tract imaging, which, however, may exacerbate the pre-existing nephropathy or have severe adverse effects. The challenge for the nephrologist is to balance the need to correctly identify chronic nephropathy against the risks related to aggressive diagnostic procedures. In order to optimize the diagnostic strategies in patients with chronic renal disease, consensus guidelines will be needed.

Aim: Sialography is considered a low invasive procedure, due to cannulation of salivary duct orifice. The aim of this study was to evaluate the morbidity of sialography using a nonionic dimeric contrast medium., Methods: A questionnaire was proposed to 90 patients who underwent parotid and submandibular sialography to reveal related symptoms as: pain, swelling, impairment to daily activities and taste alteration. Pain and swelling intensity was assessed using a visual analogue scale (VAS)., Results: Fifty-two out of ninety questionnaires were returned. Sialography was performed in 30/52 patients in the submandibular gland, 22/52 in the parotid gland. Pain during sialography was complained by 28/52 patients with a 2.4 mean VAS score. Pain after sialography, was reported by 17/52 patients with a 1.3 mean VAS score. Swelling was reported by 25/52 patients with a 2.4 mean VAS score; 48/52 patients returned immediately to daily activities; 8/52 complained different taste alterations., Conclusion: Main related symptoms for submandibular and parotid sialography are pain and swelling, spontaneously resolving after 24-48 hours in most of cases. The statistical analysis also demonstrated in patients who underwent submandibular sialography the onset of pain during the procedure is significantly related to an increase of pain after the examination. Thus in patients, who referred severe pain during sialography, antiinflammatory drugs are recommended to control the onset of pain after sialography.

Contrast-induced nephropathy is an impairment in renal function following intravascular exposure to radiographic contrast media (CM). Kidney damage may be limited to an asymptomatic increase in serum creatinine or reveal itself as acute renal failure, which can require renal replacement therapy. The aim of the present review is to describe the most recent knowledge concerning this matter. Viscosity and/or osmolality of iodinated CM might be involved in the activation of intrarenal vasoconstriction, with a subsequent decrease in glomerular filtration rate. Reduced bioavailability of physiological vasodilators, such as prostaglandins and nitric oxide, could predispose to acute renal damage. The volemic expansion and hydration of the patient, by the peri-procedural infusion of saline solutions constitutes even today the most effective prophylactic mechanism. It is probable, in fact, that in this way the dilution of CM and the inhibition of the activation of intrarenal vasoconstrictive mechanisms are obtained.

Nephrogenic systemic fibrosis (NSF) is a new, rare, and severe disease occurring in patients with renal failure who have been exposed to gadolinium. The pathogenesis of NSF is not completely known. In fact, the first warning about a significant relationship between NSF and gadolinium (a contrast medium used in magnetic resonance imaging) was only issued in 2006. No cases of NSF have been reported in Italy to date. A nationwide investigation should therefore be carried out to assess the real prevalence of NSF within the Italian uremic population. Furthermore, we need guidelines to reduce the risk of NSF in renal patients undergoing MRI with contrast medium.

Although the infusion of iodinated contrast media in diagnostic and interventional procedures may cause acute renal failure (ARF) especially in older or diabetic patients with preexisting nephropathy, these procedures are often unavoidable. Contrast medium-induced ARF is defined as an increase in serum creatinine of 0.5 mg/dL or a 25% or greater relative increase from baseline within 72 hours of iodinated contrast medium infusion. Because it is often very difficult to employ alternative diagnostic procedures, it is mandatory to adopt prophylactic protocols to prevent radiocontrast nephropathy. Renal hemodynamic lesions leading to medullary hypoxia, oxygen free radicals inducing tubular cell alterations, and parenchymal vasoconstriction are the main factors in the pathogenesis of contrast-induced ARF. Among the many proposed protocols to prevent contrast-induced renal toxicity, the most effective procedure is hydration with 1 mL/kg/h of isotonic saline solution in the 12 hours before and after contrast medium infusion. Promising results in terms of cardiac and renal protection have been reported in a recent trial with the use of high-dose N-acetylcysteine acting as an oxygen free radical scavenger: an intravenous bolus of 1200 mg N-acetylcysteine was given before coronary angiography followed by 1200 mg orally twice a day for 48 hours after the procedure. The protective effect seemed to involve not only the kidney: the drug was found to induce a significant reduction of the necrotic area in myocardial infarction.

Primary angioplasty represents the best strategy for myocardial reperfusion in ST-elevation acute myocardial infarction. However, it is associated with a high risk of developing contrast-induced nephropathy, a renal complication coupled with markedly increased morbidity and mortality rates. This paper summarizes, on the current evidence available, the clinical and prognostic relevance of renal insufficiency and contrast-induced nephropathy in acute myocardial infarction, and emphasizes new possible preventive strategies for kidney protection in this clinical setting.

Scientific evidence that prognosis of patients with ischemic heart disease, treated by either surgery or percutaneous revascularization, is similar, has led interventional cardiologists to search for an aggressive approach in percutaneous revascularization of patients with multivessel disease. It is still matter of debate which strategy is preferable between pursuing complete revascularization or performing revascularization of the culprit vessel and later of the other vessels. According to American and European guidelines for percutaneous coronary intervention (PCI) in patients with acute coronary syndromes with ST-segment elevation and multivessel disease, primary angioplasty should only be directed to the infarct-related artery (culprit vessel), with decision about PCI of non-culprit lesions guided by objective evidence of residual ischemia at later follow-up. PCI should not be performed in a non-infarct-related artery at the time of primary angioplasty in patients without hemodynamic impairment. In patients with acute coronary syndromes without persistent ST-segment elevation the decision to perform either culprit vessel or complete revascularization can be made on individual basis; in patients with favorable anatomy, the competent practitioner can perform either single or multivessel PCI with a high likelihood of success and low risk of morbidity and mortality. The endothelial dysfunction induced by coronary angioplasty, the occurrence of post-procedural infarction and contrast-induced nephropathy, the X-ray exposure, the problem of the informed consent, the procedural costs are aspects that strongly support a strategy based on staged revascularization when appropriate.

Over the last few years there has been a progressive increase in percutaneous endovascular procedures in patients with chronic renal disease, due to the high incidence of vascular disease, particularly coronary artery disease, in this population. The use of contrast medium may further worsen renal function in such patients, in some cases even accelerating the progression towards end-stage renal failure, and increase patients morbidity and mortality. In this review we discuss the role of dialysis in preventing contrast-induced nephropathy and indications to its use in patients already on dialysis treatment undergoing diagnostic or therapeutic procedures with contrast medium injection.

The administration of radiocontrast media (RC) can lead to usually a reversible form of acute renal failure (ARF) that begins soon after the contrast is administered. A functional definition of RC-induced ARF varies among different studies: most commonly reported as a proportional rise in serum creatinine (Cr), 25 or 50% above baseline or an absolute rise of 0.5-1.0 mg/dL within 48 hr after exposure to RC. Serum Cr returns to baseline over 8-12 days. Sometimes ARF is irreversible, contributing to an increase in mortality. Iodinated RC are either ionic or non-ionic and, at the concentrations required for arteriography or computed tomography, are of variable osmolality. Considering the main ARF risk factors, a rise in plasma Cr is: negligible with normal renal function, even if the patient is diabetic; 4-11% with mild to moderate renal insufficiency alone (plasma Cr between 1.5 and 4.0 mg/dL); 9-38% with mild to moderate renal insufficiency and diabetes mellitus; > or =50% if baseline plasma Cr is >4-5 mg/dL, particularly in patients with diabetic nephropathy. This risk, however, is increased further by more advanced renal dysfunction, marked volume depletion, severe heart failure, or multiple contrast studies within 72-hr. Pathogenesis is not well understood, but the mechanism by which nephrotoxins induce renal injury is generally by either vascular or direct tubular effects. In the case of RC ARF, there appears to be an influence of both mechanisms, although altered renal hemodynamics predominates. Both are thought to occur from exposure to the hyperosmolar agent. The best treatment for contrast-induced renal failure is prevention. Some preventive measures include the use, if clinically possible, of ultrasonography, magnetic resonance imaging or CT scanning without RC agents, particularly, in high-risk patients; the use of lower contrast doses and the avoidance of frequent repetitive studies; the avoidance of volume depletion or non-steroidal anti-inflammatory drugs; the administration of intravenous saline and the antioxidant acetylcysteine; the use of low or iso-osmolal non-ionic contrast agents, particularly in high risk patients.

Both the choice of contrast media for use in the cardiac catheterization laboratory, and the practice for limiting patient damage, are relevant to the quality of health care. As part of our quality assurance program, and as a preliminary step to a critical reappraisal of our current protocols, an updated review has been made of existing evidence about contrast media for this use, and about measures to prevent adverse events. Consideration was also given to evidence-based measures or drug treatment in patients at risk for anaphylactoid reactions or with renal failure, as well as to the recommended course of action in diabetic patients receiving oral biguanide agents.

Contrast-induced nephropathy (CIN) is an important and well-known cause of acute renal failure. The published literature contains numerous clinical trials describing the relative performance of various contrast agents. This review provides a comparison of different contrast agents and assesses the relative risk of clinical nephrotoxicity among them in patients with pre-existing renal insufficiency, which appear to be the patients at highest risk for CIN with all classes of these agents. Overall, the nonionic dimeric agents perform similarly to the nonionic monomeric agents in this regard.