Prevention of contrast induced nephropathy: recommendations for the high risk patient undergoing cardiovascular procedures

Anemia and periprocedural complications determine contrast-associated acute kidney injury after recanalization of chronic coronary occlusions in chronic kidney disease

BACKGROUND

Contrast-associated acute kidney injury (CA-AKI) is a potential risk associated with the percutaneous coronary interventions (PCI) for chronic total coronary occlusions (CTO) particularly with pre-existing chronic kidney disease (CKD). The determinants of CA-AKI in patients with pre-existing CKD in an era of advanced strategies of CTO recanalization techniques need to be considered for a risk evaluation of the procedure.

METHODS

A consecutive cohort of 2504 recanalization procedures for a CTO between 2013 and 2022 was analyzed. Of these, 514 (20.5%) were done in patients with CKD (estimated glomerular filtration rate < 60 ml/min based on the most recently used CKD Epidemiology Collaboration equation).

RESULTS

The rate of patients classified to have CKD would be lower with 14.2% using the Cockcroft-Gault equation, and 18.1% using the modified Modification of Diet in Renal Disease equation. The technical success was high with 94.9% and 96.8% (p = 0.04) between patients with and without CKD. The incidence of CA-AKI was 9.9% versus 4.3% (p < 0.001). The major determinants of CA-AKI in patients with CKD were the presence of diabetes and a reduced ejection fraction, as well as periprocedural blood loss, whereas a higher baseline hemoglobin and the use of the radial approach prevented CA-AKI.

CONCLUSIONS

In patients with CKD CTO PCI could be performed successfully at a higher cost of CA-AKI. Correcting preprocedural anemia and avoiding intraprocedural blood loss may reduce the incidence of CA-AKI.

Poor Prognosis of Contrast-Induced Nephropathy during Long Term Follow Up

Contrast-induced nephropathy (CIN) is known to associate with poor prognosis. However, there have been few studies for long-term follow up. The purpose of this study was to know the prognosis of CIN during a 10-year follow up. We retrospectively analyzed 528 patients who underwent coronary angiography in Jeonbuk National University Hospital (South Korea, Jeonju) between Jan 2005 to Dec 2006. We excluded the patients who required regular dialysis before study enrollment. We compared adverse events in the no CIN (group I, n=485, 61.9±11.4 years, male 64.1%) and CIN (group II, n=43, 65.7±11.1 years, male 62.8%). Baseline clinical characteristics and cardiovascular risk factors were not different between the two groups except the post-procedure creatinine level (1.04 mg/dL vs 1.84 mg/dL, p=0.0001). The higher rates of all-cause death were observed in group II at 1-year (3.7% vs 13.9%, log-rank, p=0.001), 5-years (17.9% vs 34.9%, log-rank, p=0.003), and 10-years (25.3% vs 48.8%, log-rank, p=0.000). MACE was higher in group II at 1-year (3.9% vs 11.6%, log-rank, p=0.013), 5-years (6.8% vs 20.9%, log-rank, p=0.000) and 10-years (13.4% vs 27.9%, log-rank, p=0.000). In addition, CIN was an independent predictor for 10-year MACE (adjusted HR 3.432, 95% CI 1.314-8.965, p=0.012) after propensity score matching. The worse prognosis of CIN was continuously observed after the 10-year follow-up. Our data suggests that it is worthwhile to prevent the appearance of CIN in order to improve longterm results.

A prospective study on the incidence of contrast-associated acute kidney injury after recanalization of chronic total coronary occlusions with contemporary interventional techniques

BACKGROUND

Contrast-associated acute kidney injury (CA-AKI) is a potential risk associated with the percutaneous coronary interventions (PCI) for chronic total coronary occlusions (CTO). This study should evaluate the incidence of CA-AKI in an era of advanced strategies of recanalization techniques and identify modifiable determinants.

METHODS

We analysed 1924 consecutive CTO procedures in 1815 patients between 2012 and 2019. All patients were carefully monitored at least up to 48 h after a CTO procedure for changes in renal function.

RESULTS

The incidence of CA-AKI was 5.6%, but there was no relation to the technical approach such as frequency of the retrograde technique, intravascular ultrasound or radial access. Procedures with CA-AKI had longer fluoroscopy times (37.6 vs 46.1 min; p = 0.005). The major determinants of CA-AKI were age, presence of diabetes and reduced ejection fraction, as well as chronic kidney disease stage ≥2, serum haemoglobin, and fluoroscopy time. Contrast volume or contrast volume/GFR ratio were not independent determinants of CA-AKI. Periprocedural perforations were more frequent in CA-AKI patients (11.3 vs 2.3%; p < 0.001), and in-hospital mortality was higher (2.8 vs 0.4%; p < 0.001).

CONCLUSIONS

CA-AKI was associated with the risk of in-hospital adverse events. Established patient-related risk factors for CA-AKI (age, diabetes, preexisting chronic kidney disease, low ejection fraction) were confirmed in this study. In addition, the length of the procedure, coronary perforations and low preprocedural serum haemoglobin were risk factors that might be preventable in patients at high risk for CA-AKI.

Impact of Supplementation with Omega-3 in the Prevention of Contrast-Induced Nephropathy Following Elective Percutaneous Coronary Intervention in Patients with Chronic Kidney Disease: A Randomized Placebo-Controlled Trial

Background:

Anti-oxidants were investigated in several studies as a preventive strategy for prevention of contrast-induced nephropathy (CIN). Omega-3 polyunsaturated fatty acids have antioxidant properties; however, their role in the prevention of CIN is still unknown. Therefore, in this study, we aimed to evaluate the efficacy of omega-3 supplementation in the prevention of contrast-induced nephropathy following elective percutaneous coronary intervention in patients with chronic kidney disease.

Methods:

This is a double-blinded and randomized clinical trial. Eighty eligible patients with glomerular filtration rate of 30-60 mL/min/1.73 m², scheduled to undergo elective PCI, were randomly divided into omega-3 (a single dose of 2500 mg omega-3 12 hours before PCI plus hydration therapy) or control (placebo plus hydration therapy) groups. Blood specimens for measuring serum creatinine and cystatin C were collected from each patient at baseline and 24 h after PCI.

Results:

Omega-3 did not show any significant effect on post-PCI serum creatinine and cystatin C compared to the controls. In addition, serum creatinine analysis showed that CIN occurred in 6 (16.2%) patients of the omega-3 and 4 (9.3%) patients of the control group (P = 0.50).

Conclusions:

Our results could not support the protective effect of a single dose of omega-3 in decreasing serum creatinine, serum cystatin C, and the incidence of CIN in patients with CKD undergoing PCI. To better evaluate the effect of omega-3, future studies with higher and/or multiple doses of omega-3 are highly recommended.

EFFECTS OF TEST-BOLUS AND LOW-DOSE SCAN ON CT PULMONARY ANGIOGRAPHY IMAGE QUALITY IN PATIENTS WITH DIFFERENT BODY MASS INDEXES

This study aimed to investigate different methods of obtaining high-quality Computed Tomography pulmonary angiography (CTPA) images using low-dose scanning in patients with different body mass index (BMI) values. Sixty patients with suspected pulmonary embolism were grouped based on their BMI values (BMI < 25, designated N, and BMI ≥ 25, designated O) and were assigned to receive either test bolus (TB) or bolus tracking (BT) at conventional (C) or low (L) dose. The effective dose (ED) in the N-TB-L group was lower than in the group N-TB-C (0.56 ± 0.05 vs. 3.78 ± 1.16, p < 0.001), with similar image quality (4.90 ± 0.31 vs. 4.70 ± 0.47, p = 0.120). The ED in the O-TB-L group was lower than in the O-TB-C group (0.54 ± 0.03 vs. 5.14 ± 1.34, p < 0.001), but the group O-TB-C's image quality was higher (4.65 ± 0.59 vs. 3.95 ± 0.89, p = 0.006). Groups N-TB-L versus O-TB-L, groups N-TB-L versus N-BT-L and groups O-TB-C versus O-BT-C had similar EDs (all ps > 0.05), but the image quality was different (all ps < 0.05). In conclusion, the results showed that the image quality of low-dose CTPA scanning using TB was similar to that of the conventional-dose CTPA in patients with BMI < 25 but was lower in patients with BMI ≥ 25. TB was better than BT for all patients, regardless of BMI, when receiving the same ED.

Outcomes of percutaneous coronary intervention (PCI) among patients with connective tissue disease: Propensity match analysis

BACKGROUND

Inflammation is the hallmark of coronary artery disease (CAD) and CTD. There are reports of increased prevalence of CAD among patients with CTD such as Rheumatoid Arthritis. However, there is a paucity of data regarding the outcomes of PCI among patients with CTD.

METHODS

Using the National Inpatient Database, patients that underwent PCI between 2007 and 2015 were identified using ICD-9-CM codes. Propensity match analysis with 1: 3 matching of patients with and without CTD was performed. Outcomes were acute kidney injury (AKI), access site complication (ASC), ventricular fibrillation (VF), cardiogenic shock (CS), Stroke, In-hospital mortality and hospital length of stay (LOS) compared between both groups.

RESULT

We identified 17,422 patients with CTD and matched with 52, 266 patients without CTD. Patients were predominantly female (63.1%) and white (77.2%), with a mean age of 63 ± 12.1 years. AKI (8.3% vs. 6.6%, p < 0.001), ASC (3.2% vs. 2.7%, p = 0.01) and hospital stay (4.2 ± 4.8 vs. 3.8 ± 5.2, p < 0.001) were higher among patients with CTD. There was no statistically significant difference in rates of VF, CS, stroke, and In-hospital mortality among the two groups. However, in subgroup analysis, rates of VF were lower among patients with Systemic Lupus Erythematosus (SLE) (1.5% vs. 2.2%, p = 0.006).

CONCLUSIONS

Patients with CTD undergoing PCI have a higher rate of AKI, Access site complications, and prolonged hospital stay.

Atorvastatin protects against contrast-induced acute kidney injury via upregulation of endogenous hydrogen sulfide

Background

Contrast-induced acute kidney injury (CIAKI) is the third leading cause of acute renal failure in hospitalized patients. This study was aimed to investigate whether atorvastatin could upregulate the expression of hydrogen sulfide (H₂S) and hence protect against CIAKI.

Methods

We treated male rats and NRK-52E cells by iopromide to establish in vivo and in vitro models of CIAKI. Pretreatment with atorvastatin was given in CIAKI rats to investigate its effect on CIAKI. We collected serum and urine samples to detect renal function. We obtained kidney tissue for histological analysis and detection of protein concentration. We tested the serum concentration of H₂S and renal expression of two H₂S synthetases [cystathionine γ-lyase (CSE) and cystathionine-β synthase (CBS)]. NaHS was pretreated in NRK-52E cells to testify its underlying effect on contrast-induced injury.

Results

Atorvastatin significantly ameliorated renal dysfunction and morphological changes in CIAKI rats, as well as inflammation, apoptosis, and excessive oxidative stress. Atorvastatin also markedly increased the serum concentration of H₂S and renal expression of CSE and CBS. Moreover, pretreatment with NaHS in NRK-52E cells considerably attenuated contrast-induced cell death and inflammation.

Conclusion

Atorvastatin protects against CIAKI via upregulation of endogenous hydrogen sulfide.

Acute kidney injury - A frequent and serious complication after primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction

OBJECTIVES

The aim of the study was to investigate the incidence, risk factors and long-term prognosis of acute kidney injury (AKI) in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (primary PCI).

METHOD

A large-scale, retrospective cohort study based on procedure-related variables, biochemical and mortality data collected between 2009 and 2014 at Rigshospitalet, Copenhagen, Denmark. AKI was defined as an increase in serum creatinine of 25% during the first 72 hours after the index procedure.

RESULTS

A total of 4239 patients were treated with primary PCI of whom 4002 had available creatinine measurements allowing for assessment of AKI and inclusion in this study. The mean creatinine value upon presentation for all patients was 84 μmol/l (standard deviation (SD) ±40) and 97 μmol/l (SD ±53) at peak. AKI occurred in a total of 765 (19.1%) patients. Independent risk factors for the occurrence of AKI were age, time from symptom onset to procedure, peak value of troponin-T, female sex and the contrast volume to eGFR ratio. In a multivariable adjusted analysis AKI was independently associated with a higher mortality rate at 5 years follow-up (hazard ratio 1.39 [95%-confidence interval 1.03-1.88]).

CONCLUSION

In STEMI patients treated with primary PCI one in five experiences acute kidney injury, which was associated with a substantial increase in both short- and long-term mortality.

Clinical Evaluation of a New Point-of-Care System for Chemistry Panel Testing

Background

GEM Premier ChemSTAT™ is a point-of-care (POC) system that measures Na+, K+, Ca++, Cl−, glucose, hematocrit, creatinine, blood urea nitrogen (BUN), tCO2, pH, pCO2, and lactate from a single whole blood specimen, providing rapid results in POC settings such as the emergency department (ED). Accurate measurements of creatinine in whole blood and reporting of estimated glomerular filtration rate (eGFR) can minimize adverse effects of contrast-induced nephropathy.

Methods

Heparinized whole blood specimens from the ED were analyzed on the ChemSTAT by POC staff. Method comparison was performed against the cobas Integra c501 for creatinine, BUN, and tCO2, and against the GEM Premier 4000 for all other analytes. Precision was conducted with whole blood specimens assayed in triplicate over 6 days. Creatinine results from whole blood and plasma were used for eGFR, by isotope dilution mass spectrometry-traceable Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations, and eGFR concordance was assessed.

Results

Creatinine, BUN, and tCO2 correlated well with plasma samples on the cobas, and all other analytes correlated well with whole blood specimens on the GEM Premier 4000 across the tested sample ranges. The regression slope was 0.951 to 1.047, along with a correlation coefficient (r) of ≥0.982 for all analytes. The pooled within-sample precision was 0% to 2.5% for all analytes.

Conclusions

ChemSTAT demonstrated a strong correlation with the comparative methods and excellent precision. The system's analytical performance and continuous quality management make it suitable for use in the ED to provide rapid reliable test results, which could minimize the time to treatment and improve ED efficiency.

Subtraction CT angiography in head and neck with low radiation and contrast dose dual-energy spectral CT using rapid kV-switching technique

OBJECTIVE

To investigate the application of low radiation and contrast dose spectral CT angiology using rapid kV-switching technique in the head and neck with subtraction method for bone removal.

METHODS

This prospective study was approved by the local ethics committee. 64 cases for head and neck CT angiology were randomly divided into Groups A (n = 32) and B (n = 32). Group A underwent unenhanced CT with 100 kVp, 200 mA and contrast-enhanced CT with spectral CT mode with body mass index-dependent low dose protocols. Group B used conventional helical scanning with 120 kVp, auto mA for noise index of 12 HU (Hounsfield unit) for both the unenhanced and contrast-enhanced CT. Subtraction images were formed by subtracting the unenhanced images from enhanced images (with the 65 keV-enhanced spectral CT image in Group A). CT numbers and their standard deviations in aortic arch, carotid arteries, middle cerebral artery and air were measured in the subtraction images. The signal-to-noise ratio and contrast-to-noise ratio for the common and internal carotid arteries and middle cerebral artery were calculated. Image quality in terms of bone removal effect was evaluated by two experienced radiologists independently and blindly using a 4-point system. Radiation dose and total iodine load were recorded. Measurements were statistically compared between the two groups.

RESULTS

The two groups had same demographic results. There was no difference in the CT number, signal-to-noise and contrast-to-noise ratio values for carotid arteries and middle cerebral artery in the subtraction images between the two groups (p > 0.05). However, the bone removal effect score [median (min-max)] in Group A [4 (3-4)] was rated better than in Group B [3 (2-4)] (p < 0.001), with excellent agreement between the two observers (κ > 0.80). The radiation dose in Group A (average of 2.64 mSv) was 57% lower than the 6.18 mSv in Group B (p < 0.001). The total iodine intake in Group A was 13.5g, 36% lower than the 21g in Group B.

CONCLUSION

Spectral CT imaging with rapid kV-switching in the subtraction angiography in head and neck provides better bone removal with significantly reduced radiation and contrast dose compared with conventional subtraction method. Advances in knowledge: This novel method provides better bone removal with significant radiation and contrast dose reduction compared with the conventional subtraction CT, and maybe used clinically to protect the thyroid gland and ocular lenses from unnecessary high radiation.

Oxidative stress and kidney injury in trans-radial catheterization

Oxidative stress is linked to coronary artery disease and is a major mechanism in contrast-induced nephropathy. Trans-radial approach in coronary angiography (CA) with minimized peri-procedural bleeding is expected to reduce acute kidney injury incidence. In the present study, oxidative stress patterns observed in radial CA and their associations with early manifestations of kidney injury are described. A total of 20 stable coronary disease patients submitted to CA and 17 sex-matched patients undergoing computed tomography for myoskeletal reasons were enrolled. Reduced glutathione, catalase, thiobarbituric acid reactive species (TBARS) levels and total anti-oxidant status were measured at various time points postangiography. In ischemic patients baseline TBARS levels were 2-fold lower compared to controls, while carbonyls levels were 35% higher. Glutathione was almost 4-fold lower than the control group. Glutathione and lipid peroxidation in ischemic patients gradually increased after contrast medium administration and reached 180% (P<0.001) and 20% (P=0.021) after 4–6 h, respectively. Four patients presented early evidence of contrast-induced nephropathy postangiography, while no control patient developed acute kidney injury. In the multiple logistic regression analysis, only the creatinine levels at baseline influenced the frequency of early contrast-induced nephropathy development (β =0.36, 95% CI: 0.285–0.438, P=0.01). Glutathione low levels were dominant in the baseline values of ischemic patients who developed contrast-induced nephropathy. Glutathione levels rapidly increased while protein oxidation decreased at the expense of lipid peroxidation. In conclusion, early oxidative stress changes occur in trans-radial CA patients with a mild profile, sufficient to mobilize patient antioxidant defenses.

Randomized trial of one-hour sodium bicarbonate vs standard periprocedural saline hydration in chronic kidney disease patients undergoing cardiovascular contrast procedures

Background

Guidelines advise periprocedural saline hydration for prevention of contrast induced-acute kidney injury (CI-AKI). We analysed whether 1-hour sodium bicarbonate hydration administered solely prior to intra-arterial contrast exposure is non-inferior to standard periprocedural saline hydration in chronic kidney disease (CKD) patients undergoing elective cardiovascular diagnostic or interventional contrast procedures.

Methods

We performed an open-label multicentre non-inferiority trial between 2011–2014. Patients were randomized to 1 hour pre-procedure sodium bicarbonate hydration (250 ml 1.4%, N = 168) or 4–12 hours saline hydration (1000 ml 0.9%, N = 165) prior to and following contrast administration (2000 ml of saline total). Primary outcome was the relative serum creatinine increase (%) 48–96 hours post contrast exposure. Secondary outcomes were: incidence of CI-AKI (serum creatinine increase>25% or >44μmol/L), recovery of renal function, the need for dialysis, and hospital costs within two months follow-up.

Results

Mean relative creatinine increase was 3.1% (95%CI 0.9 to 5.2%) in the bicarbonate and 1.1% (95%CI -1.2 to 3.5%) in the saline arm, mean difference 1.9% (95%CI -1.2 to 5.1%, p-non-inferiority <0.001). CI-AKI occurred in 11 (6.7%) patients randomized to sodium bicarbonate and 12 (7.5%) to saline (p = 0.79). Renal function did not fully recover in 40.0% and 44.4% of CI-AKI patients, respectively (p = 0.84). No patient required dialysis. Mean costs for preventive hydration and clinical preparation for the contrast procedure were $1158 for sodium bicarbonate vs. $1561 for saline (p < 0.001).

Conclusion

Short hydration with sodium bicarbonate prior to elective cardiovascular diagnostic or therapeutic contrast procedures is non-inferior to standard periprocedural saline hydration in CKD patients with respect to renal safety and results in considerable healthcare savings.

Trial registration

Netherlands Trial Register (http://www.trialregister.nl/trialreg/index.asp), Nr NTR2699

Longitudinal Risk of Adverse Events in Patients With Acute Kidney Injury After Percutaneous Coronary Intervention: Insights From the National Cardiovascular Data Registry

BACKGROUND

Acute kidney injury (AKI) remains a common complication after percutaneous coronary intervention (PCI) and is associated with adverse in-hospital patient outcomes. The incidence of adverse events after hospital discharge in patients having post-PCI AKI is poorly defined, and the relationship between AKI and outcomes after hospital discharge remains understudied.

METHODS AND RESULTS

Using the National Cardiovascular Data Registry CathPCI registry, we assessed the incidence of AKI among Medicare beneficiaries after PCI from 2004 to 2009 and subsequent post-discharge adverse events at 1 year. AKI was defined using Acute Kidney Injury Network (AKIN) criteria. Adverse events included death, myocardial infarction, bleeding, and recurrent kidney injury. Using Cox methods, we determined the relationship between in-hospital AKI and risk of post-discharge adverse events by AKIN stage. In a cohort of 453 475 elderly patients undergoing PCI, 39 850 developed AKI (8.8% overall; AKIN stage 1, 85.8%; AKIN 2/3, 14.2%). Compared with no AKI, in-hospital AKI was associated with higher post-discharge hazard of death, myocardial infarction, or bleeding (AKIN 1: hazard ratio [HR], 1.53; confidence interval [CI], 1.49-1.56 and AKIN 2/3: HR, 2.13; CI, 2.01-2.26), recurrent AKI (AKIN 1: HR, 1.70; CI, 1.64-1.76; AKIN 2/3: HR, 2.22; CI, 2.04-2.41), and AKI requiring dialysis (AKIN 1: HR, 2.59; CI, 2.29-2.92; AKIN 2/3: HR, 4.73; CI, 3.73-5.99). For each outcome, the highest incidence was within 30 days.

CONCLUSIONS

Post-PCI AKI is associated with increased risk of death, myocardial infarction, bleeding, and recurrent renal injury after discharge. Post-PCI AKI should be recognized as a significant risk factor not only for in-hospital adverse events but also after hospital discharge.

Association Between Chronic Kidney Disease and Rates of Transfusion and Progression to End-Stage Renal Disease in Patients Undergoing Transradial Versus Transfemoral Cardiac Catheterization-An Analysis From the Veterans Affairs Clinical Assessment Reporting and Tracking (CART) Program

BACKGROUND

Patients with chronic kidney disease (CKD) are at increased risk for bleeding, transfusion, and dialysis after cardiac catheterization. Whether rates of these complications are increased in this high-risk population undergoing transradial access compared with transfemoral access is unknown.

METHODS AND RESULTS

From the Veterans Affairs (VA) Clinical Assessment Reporting and Tracking program, we identified 229 108 patients undergoing cardiac catheterization between 2007 and 2014, of which 48 155 (21.0%) had baseline glomerular filtration rate (GFR) between 15 and 59 mL/min. We used multivariable Cox modeling to determine the independent association between transradial access and postprocedure transfusion as well as progression to new dialysis by degree of renal dysfunction. Overall, 35 979 (15.7%) of patients underwent Transradial access. Transradial patients tended to be slightly younger, but, overall, had similar rates of CKD compared to transfemoral patients (24.3% vs 27.1%). Transradial patients had longer fluoroscopy times (7.2 vs 6.0 minutes; P<0.001), but lower contrast use (85.0 vs 100.0 mL; P<0.001). The estimated rate of blood transfusion within 48 hours was lower among transradial patients (0.85% vs 1.01%) as were rates of new dialysis at 1 year (0.58% vs 0.71%). After multivariable adjustment, transradial access was associated with lower rates of progression to dialysis at 1 year overall (hazard ratio [HR], 0.83; 95% CI, 0.70-0.98), with no trend of increased risk for dialysis by degree of CKD compared with transfemoral access. Transradial access was associated with greater reduction in transfusion rates with increasing degree of CKD (P value for trend=0.04: non-CKD: HR, 0.99; 95% CI, 0.73-1.34; GFR 45-59 mL/min: HR, 0.93; 95% CI, 0.70-1.23; GFR 30-44 mL/min: HR, 0.73; 95% CI, 0.51-1.03; GFR 15-29 mL/min: HR, 0.43; 95% CI, 0.20-0.90).

CONCLUSIONS

Among patients undergoing cardiac catheterization in the VA health system, transradial access was associated with lower risk for postprocedure transfusion within 48 hours among patients with more-severe CKD, and with lower risk of progression to end-stage renal disease at 1 year compared with transfemoral access. These data provide additional evidence that transradial access may provide significant benefit in this high-risk population.

Usefulness of C-Reactive Protein as a Predictor of Contrast-Induced Nephropathy After Percutaneous Coronary Interventions in Patients With Acute Myocardial Infarction and Presentation of a New Risk Score (Athens CIN Score)

Contrast-induced nephropathy (CIN) after percutaneous coronary interventions (PCI) in patients with acute myocardial infarction (AMI) is associated with high morbidity and mortality, whereas there are no reliable predictive tools easy to use. We evaluated the association of pre-procedural high-sensitivity C-reactive protein (hsCRP) with the development of CIN and integrated this variable in a new risk CIN prediction model. Consecutive patients (348 AMI subjects) who underwent PCI were recruited. Creatinine levels were detected on admission, at 24, 48, and 72 hours after PCI. CIN was defined using the Kidney Disease: Improving Global Outcomes criteria. In our study population (348 subjects), CIN developed in 54 patients (15.5%). Patients with CIN were older and had higher hsCRP at admission, whereas their ejection fraction (EF) and glomerular filtration rate (GFR) were lower. In multivariate analysis after incorporating potential confounders, hsCRP at admission was an independent predictor of CIN (OR for logCRP 2.00, p = 0.01). In receiver-operating characteristic curve analysis, a model incorporating hsCRP, age, GFR, and EF showed good accuracy in predicting the development of CIN (c statistic 0.84, 95% confidence interval 0.793 to 0.879). A total risk score derived from the proposed model yielded significant positive and negative predictive values and classified 85.8% of our patients correctly for CIN. In conclusion, measuring hsCRP levels at admission in patients who underwent PCI for AMI may offer additional assistance in predicting the development of CIN. A model incorporating age and admission hsCRP, EF, and GFR emerged as an accurate tool for predicting CIN in this context.

Strategies for assessing renal function prior to outpatient contrast-enhanced CT: a UK survey

OBJECTIVE

To identify current UK screening practices prior to contrast-enhanced CT. To determine the patient management strategies to minimize the risk of contrast-induced acute kidney injury (CI-AKI) risk in outpatients.

METHODS

An invitation to complete an electronic survey was distributed to the CT managers of 174 UK adult National Health Service hospital trusts. The survey included questions related to local protocols and national guidance on which these are based. Details of the assessment of renal function prior to imaging and thresholds for contrast contraindication and patient management were also sought.

RESULTS

A response rate of 47.1% was received. Almost all sites had a policy in place for contrast administration (n = 80/82; 97.6%). The majority of sites require a blood test on outpatients undergoing a contrast-enhanced CT scan (n = 75/82; 91.5%); however, some (15/75; 20.0%) sites only check the result in patients at high risk and a small number (7/82; 8.5%) of sites indicated that it was a referrer responsibility. The estimated glomerular filtration rate (eGFR) or serum creatinine (SCr) result threshold at which i.v. contrast was contraindicated varied and 19 different threshold levels of eGFR or SCr were identified, each leading to different prophylactic strategies. Inconsistency was noted in the provision of follow-up blood tests after contrast administration.

CONCLUSION

The wide variation in practice reflects inconsistencies in published guidance. Evidence-based consensuses of which patients to test and subsequent risk thresholds will aid clinicians identify those patients in which the risk of CI-AKI is clinically significant but manageable. There is also a need to determine the value of the various prophylactic strategies, follow-up regimen and efficient service delivery pathways. Advances in knowledge: This survey has identified that further work is required to define which patients are high risk, confirm those which require renal function testing prior to contrast administration and how best to manage patients at risk of CI-AKI. The role of new technologies within this service delivery pathway requires further investigation.

Comparison of Approaches to Revascularization in Patients With Multivessel Coronary Artery Disease Presenting With ST-Segment Elevation Myocardial Infarction: Meta-analyses of Randomized Control Trials

BACKGROUND

Significant controversy exists regarding the best approach for nonculprit vessel revascularization in patients with multivessel coronary artery disease presenting with ST-segment elevation myocardial infarction. We conducted a systematic investigation to pool data from current randomized controlled trials (RCTs) to assess optimal treatment strategies in this patient population.

METHODS AND RESULTS

A comprehensive search of SCOPUS from inception through May 2015 was performed using predefined criteria. We compared efficacy and safety outcomes of different approaches by categorizing the studies into 3 groups: (1) complete revascularization (CR) versus culprit lesion revascularization (CL) at index hospitalization, (2) CR at index hospitalization versus staged revascularization (SR) of nonculprit vessels at a separate hospitalization, and (3) comparison of SR versus CL. Eight eligible RCTs met the inclusion criteria: (1) CR versus CL (6 RCTs, n=1727) (2) CR versus SR (3 RCTs, n=311), and (3) SR versus CL (1 RCT, n=149). We observed significantly lower rates of major adverse cardiovascular events, revascularization, and repeat percutaneous coronary interventions among patients treated with CR and SR compared with a CL approach (P<0.05). The rates of all-cause mortality, cause-specific mortality, major bleeding, reinfarction, stroke, and contrast-induced nephropathy did not differ in the CR arm compared with the CL arm. The rates of these outcomes were similar in the CR and SR arms.

CONCLUSION

Results suggest that CR and SR compared with CL reduce major adverse cardiovascular event and revascularization rates primarily by lowering repeated percutaneous coronary intervention rates. We did not observe any increase in the rate of adverse events while using a CR or SR strategy compared with a CL approach. Current guidelines discouraging CR need to be reevaluated, and clinical judgment should prevail in treating multivessel coronary artery disease patients with ST-segment elevation myocardial infarction as data from larger RCTs accumulate.

Quality Markers in Cardiology. Main Markers to Measure Quality of Results (Outcomes) and Quality Measures Related to Better Results in Clinical Practice (Performance Metrics). INCARDIO (Indicadores de Calidad en Unidades Asistenciales del Área del Corazón): A SEC/SECTCV Consensus Position Paper

Cardiology practice requires complex organization that impacts overall outcomes and may differ substantially among hospitals and communities. The aim of this consensus document is to define quality markers in cardiology, including markers to measure the quality of results (outcomes metrics) and quality measures related to better results in clinical practice (performance metrics). The document is mainly intended for the Spanish health care system and may serve as a basis for similar documents in other countries.

Factors Contributing to Acute Kidney Injury and the Impact on Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement

BACKGROUND

Transcatheter aortic valve replacement (TAVR) patients are at a high risk of acute kidney injury (AKI). This study aimed to investigate AKI and the relationship with iodinated contrast media (ICM), whether there are significant pre- or peri- procedural variables predicting AKI, and whether AKI impacts on hospital length of stay and mortality.

METHODS

Serum creatinine (SC) levels pre- and post- (peak) TAVR were recorded in 209 consecutive TAVR patients. AKI was defined by the Valve Academic Research Consortium 2 (VARC2) criteria. Baseline characteristics, procedural variables, hospital length of stay (LOS) and mortality at 72hours, 30 days and one year were analysed.

RESULTS

Eighty-two of 209 (39%) patients suffered AKI. Mean ICM volume was 228cc, with no difference between patients with AKI and those with no AKI (227cc (213-240(95%CI)) vs 231cc (212-250) p=0.700)). Univariate and multivariate analysis demonstrated that chronic kidney disease, respiratory failure, previous stroke, the need for blood transfusion and valve repositioning were all predictors of AKI. Acute kidney injury increased LOS (5.6 days (3.8 - 7.5) vs 3.2 days (2.6 - 3.9) no AKI (P=0.004)) but was not linked to increased mortality. Mortality rates did increase with AKI severity.

CONCLUSION

Acute kidney injury is a common complication of TAVR. The severity of AKI is important in determining mortality. Acute kidney injury appears to be independent of ICM use but pre-existing renal impairment and respiratory failure were predictors for AKI. Transcatheter aortic valve replacement device repositioning or retrieval was identified as a new risk factor impacting on AKI.

Comparison of combination therapy of high-dose oral N-acetylcysteine and intravenous sodium bicarbonate hydration with individual therapies in the reduction of Contrast-induced Nephropathy during Cardiac Catheterisation and Percutaneous Coronary Intervention (CONTRAST): A multi-centre, randomised, controlled trial

INTRODUCTION

N-acetylcysteine (NAC) and sodium bicarbonate (SOB) therapies may prevent contrast-induced nephropathy (CIN). However, the efficacy of using combination over individual therapies was not established, and there was no large randomised study comparing abbreviated SOB therapy with conventional sustained saline pre-hydration with oral NAC.

METHODS

In a multi-centre, open-label, randomised, controlled trial (NCT00497328), we prospectively enrolled 548 patients with at least moderate renal impairment undergoing cardiac catheterisation with or without percutaneous coronary intervention. Patients were randomly assigned to 3 groups: 1) NAC: 154 mEq/L sustained sodium chloride regime (1 mL/kg/h 12 h before, during and 6h after the procedure) with oral NAC at 1.2g bid for 3 days (n=185); 2) SOB: 154 mEq/L abbreviated SOB regime at 3 mL/kg/h 1h before the procedure, and 1 mL/kg/h during and 6h after the procedure (n=182); and 3) COM: combination of abbreviated SOB regime and oral NAC (n=181). The primary end point was incidence of CIN. The secondary end points were rise in serum creatinine, hospitalisation duration, haemodialysis, morbidity and mortality within 30 days.

RESULTS

The 3 groups had similar baseline characteristics: age 68 ± 10 years, 76% male, 48% diabetic and baseline glomerular filtration rate (GFR) 47.7 ± 13.0 mL/min. There were 41 (8.8%) patients with GFR<30. The CIN incidences were NAC 6.5%, SOB 12.8% and COM 10.6%. The COM regimen was not superior to either the NAC (relative risk (RR)=1.61, 95% confidence interval (CI): 0.76 to 3.45, p=0.225) or SOB (RR=0.83, 95% CI: 0.44 to 1.56, p=0.593) regimens. The CIN incidence was lower in the NAC group than the SOB group (adjusted odds ratio (OR)=0.40, 95% CI: 0.17 to 0.92; p=0.032). Multivariate analysis showed contrast volume (OR=1.99, 95% CI: 1.33 to 2.96, p<0.001 per 100mL), female (OR=2.47, 95% CI: 1.22 to 5.00, p=0.012) and diabetes (OR=2.03, 95% CI: 1.03 to 3.99, p=0.041) were independent risk predictors. There were no differences in the secondary outcomes among the 3 groups.

CONCLUSION

The combination regimen was not superior to individual regimens in preventing CIN in patients with baseline renal impairment. There was a trend suggesting that the 12-hour sustained sodium chloride pre-hydration regimen was more protective than the 1-hour abbreviated SOB regimen.

Contrast-Induced Nephropathy: Identifying the Risks, Choosing the Right Agent, and Reviewing Effective Prevention and Management Methods

With the rise in the use of intravenous iodinated contrast media for both computed tomography scan and angiographic studies, there is a greater likelihood of complications. One of the most well-known adverse effects is contrast-induced media nephropathy, which is also called contrast-induced acute kidney injury. This is third most common cause of hospital acquired acute renal failure. It is associated with an increase in morbidity, mortality, and greater financial burden on healthcare system. Because of these factors, it is important for the radiologist to not only recognize risk factors, as well as the signs and symptoms, but also to know how to manage patients appropriately.

Safety and efficacy of carbon dioxide and intravascular ultrasound-guided stenting for renal artery stenosis in patients with chronic renal insufficiency

We evaluated the feasibility, safety, and mid-term outcomes of renal artery stenting using carbon dioxide (CO₂) digital subtraction angiography and intravascular ultrasound (IVUS) for patients with renal insufficiency and significant atherosclerotic renal artery stenosis (RAS). Eighteen consecutive patients with chronic renal insufficiency underwent renal artery stenting under the guidance of CO₂ angiography and IVUS without contrast media. Renal function and blood pressure were assessed pre- and postintervention. A total of 27 de novo RAS in 18 patients (15 males; mean age: 72 ± 9 years) with renal insufficiency were treated by renal artery stenting with the combined use of the CO₂ angiography and IVUS without any procedural complications. Although the mean serum creatinine concentration preprocedure and 6 months after treatment did not change (2.7 ± 1.0-2.4 ± 1.1 mg/dL), blood pressure significantly decreased 6 months after stenting (158 ± 10-147 ± 11 mm Hg, P < .01).

Adaptation of contrast injection protocol to tube potential for cardiovascular CT

OBJECTIVE

The purpose of this study was to investigate and validate adaptation of a cardiovascular CT angiography contrast injection protocol for lower tube potential.

MATERIALS AND METHODS

Eighty-three patients evaluated for thoracic aortic disease with a 256-MDCT scanner were imaged at 120 kV (group 1) or 100 kV (group 2) with the same contrast protocol (90 mL iopromide 370 mg I/mL at 3.5 mL/s). A pharmacokinetic model was validated and used to simulate aortic attenuation in group 2 patients with 20%, 33%, and 44% reduction in contrast volume. A 44% volume reduction was applied to 50 additional patients who underwent imaging at 100 kV (group 3). Patient characteristics, scanning and radiation parameters, and objective and subjective image indexes were compared among groups.

RESULTS

Group 2 patients had higher mean aortic blood attenuation (399±61 HU) than group 1 patients (281±48 HU) (p<0.001) but similar image noise. Group 3 and group 1 patients had similar mean aortic attenuation and noise. Subjective assessment of image quality indicated that group 3 and group 1 had comparable percentages of images with good or excellent diagnostic confidence scores (reader 1, 98% vs 96%; reader 2, 96% vs 96%).

CONCLUSION

Lower tube potential (100 kV) for cardiothoracic CT could be accompanied by a 44% reduction in contrast volume with satisfactory aortic blood-pool attenuation in most patients. More personalized adaptation of the contrast protocol that takes into account patient characteristics and tube potential is necessary to ensure sufficient contrast enhancement for all patients.

Long-Term Follow-Up of Patients at High Risk for Nephropathy After Contrast Exposure

Contrast medium-induced acute kidney injury (CI-AKI) is associated with morbidity and mortality, but the long-term outcomes of patients who do not develop CI-AKI remain unknown. We assessed clinical end points during long-term follow-up in patients at high risk for nephropathy who did not develop CI-AKI. Patients (n = 135) with impaired renal function (estimated glomerular filtration rate: 30-60 mL/min/1.73 m(2)) were divided into 2 groups according to contrast media (CM) exposure. The primary end point of this study was a composite outcome measure of death or renal failure requiring dialysis. Multivariate analyses identified CM exposure to be independently associated with major adverse long-term outcomes (hazard ratio: 2.3; 95% confidence interval, 1.34-6.52; P = .018). Even when CM exposure does not cause CI-AKI in patients with impaired renal function, in the long term, primary end points occur more frequently in patients exposed to CM than in those with no CM exposure.

Accuracy of point-of-care serum creatinine devices for detecting patients at risk of contrast-induced nephropathy: a critical overview

Contrast-induced nephropathy (CIN) is a common event in hospitals, with reported incidences ranging from 1 to 30%. Patients with underlying kidney disease have an increased risk of developing CIN. Point-of-care (POC) creatinine devices are handheld devices capable of providing quantitative data on a patient's kidney function that could be useful in stratifying preventive measures. This overview aims to synthesize the current evidence on diagnostic accuracy and clinical utility of POC creatinine devices in detecting patients at risk of CIN. Five databases were searched for diagnostic accuracy studies or clinical trials that evaluated the usefulness of POC devices in detecting patients at risk of CIN. Selected articles were critically appraised to assess their individual risk of bias by the use of standard criteria; 13 studies were found that addressed the diagnostic accuracy or clinical utility of POC creatinine devices. Most studies incurred a moderate to high risk of bias. Overall concordance between POC devices and reference standards (clinical laboratory procedures) was found to be moderate, with 95% limits of agreement often lying between -35.4 and +35.4 µmol/L (-0.4 and +0.4 mg/dL). Concordance was shown to decrease with worsening kidney function. Data on the clinical utility of these devices were limited, but a significant reduction in time to diagnosis was reported in two studies. Overall, POC creatinine devices showed a moderate concordance with standard clinical laboratory creatinine measurements. Several biases could have induced optimism in these estimations. Results obtained from these devices may be unreliable in cases of severe kidney failure. Randomized trials are needed to address the clinical utility of these devices.

Cardiac critical care after transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) is a new therapy for severe aortic stenosis now available in the United States. Initial patients eligible for TAVR are defined by high operative risk, with advanced age and multiple comorbidities. Following TAVR, patients experience acute hemodynamic changes and several possible complications, including hypotension, vascular injury, anemia, stroke, new-onset atrial fibrillation, conduction disturbances and kidney injury, requiring an acute phase of intensive care. Alongside improvements in TAVR technology and technique, improvements in care after TAVR may contribute to improved outcomes. This review presents an approach to post-TAVR critical care and identifies directions for future research.

Usefulness of the SYNTAX score to predict acute kidney injury after percutaneous coronary intervention (from the Acute Catheterization and Urgent Intervention Triage Strategy Trial)

The synergy between percutaneous coronary intervention (PCI) with Taxus and cardiac surgery (SYNTAX) score (SS) has prognostic utility for ischemic outcomes in patients undergoing PCI. Acute kidney injury (AKI) after PCI has been demonstrated to be associated with adverse outcomes. However, the relation between the SS and AKI after PCI has yet to be fully investigated. We therefore sought to study this relation in the formal angiographic substudy of the large Acute Catheterization and Urgent Intervention Triage Strategy trial. We stratified 2,268 patients who underwent PCI for non-ST-segment elevation acute coronary syndromes by postprocedural AKI status and by SS tertiles (SS<7, 7 to 12, and >12). We also assessed rates of in-hospital, 30-day, and 1-year adverse outcomes. A total of 226 patients (10%) developed AKI, and rates in the highest Acute Catheterization and Urgent Intervention Triage Strategy SS tertile (>12) were significantly greater than those in the intermediate (7 to 12) and lowest tertiles (<7; 13% vs 8.9% vs 7.7%, respectively, p=0.002). By multivariable analysis, the SS was independently associated with AKI (odds ratio per 10 SS points 1.22, 95% confidence interval 1.04 to 1.43, p=0.02. Rates of major adverse cardiovascular events and net adverse clinical events increased significantly by SS tertile and were more common in patients who developed AKI. Patients who developed AKI experienced higher in-hospital, 30-day, and 1-year rates of mortality. In this large study, the SS was independently associated with AKI after PCI for non-ST-segment elevation acute coronary syndromes, and patients who developed AKI experienced worse short-term and long-term outcomes.

Development of an easily applicable risk score model for contrast-induced nephropathy prediction after percutaneous coronary intervention: a novel approach tailored to current practice

BACKGROUND

Several risk factors for contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) have been identified. The cumulative effect of these risk factors on renal function has been assessed with the development of risk score models in a number of studies. However, concerns were raised that estimates of the risk attributable to individual factors may be unreliable. We sought to develop a simple risk score for developing CIN after PCI irrespective of use of prophylactic measures and also capturing the effect of pre-intervention medication and presence of various co-morbidities.

METHODS

Consecutive patients treated with elective or urgent PCI at our cardiac catheterization laboratory were enrolled (derivation cohort n = 488, validation cohort n = 200). CIN was defined as increase ≥ 25% and/or ≥ 0.5 mg/dl in serum creatinine at 48 h after PCI vs baseline. Multivariable logistic regression analysis was then performed to identify independent predictors of CIN (pre-existing renal disease, metformin use, history of previous PCI, peripheral arterial disease and ≥ 300 ml of contrast volume).

RESULTS

The incidence of CIN in the development cohort was 10.2% with a significant trend across increasing score values (p < 0.001). The model demonstrated good discriminating power (c-statistic 0.759) and excellent calibration (calibration slope 0.91). The model was validated internally by bootstrapping in 1000 samples (c-statistic 0.753) and in a cohort of 200 patients (c-statistic 0.864) demonstrating stable performance.

CONCLUSIONS

The proposed risk score is easily applicable and allows for practically simple risk assessment compared to other published scores while at the same time overcomes drawbacks of previous model designs.

A novel tool for reliable and accurate prediction of renal complications in patients undergoing percutaneous coronary intervention

OBJECTIVES

The aim of the study was to develop and validate a tool for predicting risk of contrast-induced nephropathy (CIN) in patients undergoing contemporary percutaneous coronary intervention (PCI).

BACKGROUND

CIN is a common complication of PCI and is associated with adverse short- and long-term outcomes. Previously described risk scores for predicting CIN either have modest discrimination or include procedural variables and thus cannot be applied for pre-procedural risk stratification.

METHODS

Random forest models were developed using 46 pre-procedural clinical and laboratory variables to estimate the risk of CIN in patients undergoing PCI. The 15 most influential variables were selected for inclusion in a reduced model. Model performance estimating risk of CIN and new requirement for dialysis (NRD) was evaluated in an independent validation data set using area under the receiver-operating characteristic curve (AUC), with net reclassification improvement used to compare full and reduced model CIN prediction after grouping in low-, intermediate-, and high-risk categories.

RESULTS

Our study cohort comprised 68,573 PCI procedures performed at 46 hospitals between January 2010 and June 2012 in Michigan, of which 48,001 (70%) were randomly selected for training the models and 20,572 (30%) for validation. The models demonstrated excellent calibration and discrimination for both endpoints (CIN AUC for full model 0.85 and for reduced model 0.84, p for difference <0.01; NRD AUC for both models 0.88, p for difference = 0.82; net reclassification improvement for CIN 2.92%, p = 0.06).

CONCLUSIONS

The risk of CIN and NRD among patients undergoing PCI can be reliably calculated using a novel easy-to-use computational tool (https://bmc2.org/calculators/cin). This risk prediction algorithm may prove useful for both bedside clinical decision making and risk adjustment for assessment of quality.