Cardiovascular disease and chronic kidney disease: insights and an update

Kidney Transplantation and Cardiovascular Events Among Patients With End-Stage Renal Disease Due to Lupus Nephritis: A Nationwide Cohort Study

OBJECTIVE

To assess the potential impact of kidney transplantation on cardiovascular (CV) events among patients with end-stage renal disease (ESRD) due to lupus nephritis (LN).

METHODS

In a nationwide cohort study, we identified all patients with LN-ESRD enrolled in the US Renal Data System who were waitlisted for a kidney transplant and enrolled in Medicare between January, 2000 and December, 2016. The primary outcome was incident CV events, including myocardial infarction (MI) and ischemic cerebrovascular accident (CVA). We used time-dependent Cox regression to estimate the hazard ratios (HRs) of these outcomes associated with kidney transplant as a time-varying exposure, adjusting for sex, age, race, ethnicity, geographic region, year of ESRD onset, first ESRD treatment modality (e.g., hemodialysis or peritoneal dialysis), Charlson Comorbidity Index score, and history of prior organ transplants.

RESULTS

Of 5,963 waitlisted patients with LN-ESRD, 3,209 (54%) had a kidney transplant during the study period. The majority were female (82%), and African American patients represented 48% of waitlisted patients and 43% of transplanted patients. Kidney transplantation was associated with a lower risk of incident CV events (adjusted HR 0.31 [95% confidence interval (95% CI) 0.18-0.53]) as well as lower risks of MI and CVA (adjusted HRs 0.13 [95% CI 0.08-0.34] and 0.30 [95% CI 0.16-0.54], respectively).

CONCLUSION

Kidney transplantation was associated with a reduced risk of CV events, including MI and CVA, in patients with LN-ESRD. Our findings highlight the importance of identifying barriers to transplantation in this population, as improved access could reduce CV morbidity.

Randomized study evaluating the efficacy and safety of switching from an an abacavir/lamivudine-based regimen to an elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide single-tablet regimen

OBJECTIVE

To evaluate the efficacy and safety of switching from an abacavir/lamivudine (ABC/3TC)-based regimen to an elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) single-tablet regimen in virologically suppressed, HIV-1-infected adults.

DESIGN

Randomized, open-label, noninferiority study.

METHODS

Participants with HIV-1 RNA levels less than 50 copies/ml receiving ABC/3TC plus a third agent for at least 6 months were randomized 2 : 1 to switch immediately to E/C/F/TAF (immediate-switch group) for 48 weeks or to continue receiving ABC/3TC plus a third agent for 24 weeks followed by E/C/F/TAF for 24 weeks (delayed-switch group). The primary endpoint was HIV-1 RNA less than 50 copies/ml at Week 24 by Food and Drug Administration Snapshot algorithm (-12% noninferiority margin).

RESULTS

Baseline characteristics of 274 participants (183 in immediate-switch group and 91 in delayed-switch group) were similar. Virologic response was maintained at Week 24 by 93.4 and 97.8% of participants in the immediate-switch and delayed-switch groups, respectively, with a treatment difference of -4.4% (95% confidence interval: -9.4 to 1.9%), confirming noninferiority. Adverse events of any grade were similar between groups through Week 24 (66% E/C/F/TAF, 64% ABC/3TC); adverse event-related drug discontinuations occurred in 4% of participants switching to E/C/F/TAF (no discontinuations because of renal events) and no participants continuing ABC/3TC. Renal biomarkers of urine albumin:creatinine and beta-2-microglobulin:creatinine ratios significantly improved on E/C/F/TAF. Self-reported treatment satisfaction was significantly higher with E/C/F/TAF.

CONCLUSION

Switching to E/C/F/TAF was noninferior to continuing ABC/3TC plus a third agent for maintenance of HIV RNA suppression at Week 24. This study supports E/C/F/TAF as an efficacious and well tolerated option for participants switching from ABC/3TC-based regimens.

In-Hospital Mortality and Major Adverse Cardiovascular Events after Kidney Transplantation in the United States

Background: Kidney transplantation (KT) is the treatment of choice for end-stage kidney disease. Cardiovascular disease is a major determinant of morbidity and mortality in patients with KT. Temporal trends in perioperative cardiovascular outcomes after KT are understudied, especially in light of an aging KT waitlist population. Methods: We performed a retrospective observational cohort study using the National Inpatient Sample for the years 2004–2013. All adult patients undergoing KT were identified using the appropriate International Classification of Diseases, 9th Revision, Clinical Modification codes. Demographic and hospital characteristics, discharge disposition, payer status, and major adverse cardiovascular events (MACEs) were summarized using summary statistics. Multivariate logistic regression was used to identify predictors of MACEs in the perioperative period of KT. Results: A total of 147,431 KTs were performed between 2004 and 2013. The mean age at KT went up from 48.1 to 51.8 years from 2004 to 2013. Medicare was the primary payer for 59.6% of the KTs. Overall average perioperative mortality was 0.5%, median length of stay was 5 days, and 6.5% of patients experienced an MACE, 78% of which were heart failures (HFs). Important predictors of perioperative MACEs were age ≥65 years (OR = 2.14), Medicare as primary payer (OR = 1.51), diabetes (OR = 1.46), recreational drug use (OR = 1.72), pulmonary circulation disorders (OR = 3.28), and malnutrition (OR = 1.91). Conclusion: Despite increases in age at the time of KT, the absolute risk of perioperative MACEs has remained stable from 2004 to 2013. HF is a major component of postoperative MACEs in KT. Malnutrition and pulmonary hypertension are major nontraditional predictors of perioperative MACE outcomes.

Lack of association between cystatin C and different coronary atherosclerotic manifestations

Cystatin C (CysC) is known to be related to cardiovascular disease (CVD), including the presence and severity of coronary artery disease (CAD) and future clinical events. In this study, the association between CysC levels and (1) coronary artery calcification (CAC) in asymptomatic individuals from the general population as well as (2) different subgroups of patients with suspected or definite acute myocardial infarction (MI) was investigated. CysC levels were measured in serum from asymptomatic individuals as part of a screening study for CAC using non-contrast cardiac CT scan (N = 1039) as well as in subgroups of hospitalized patients with a suspected MI (N = 769). CysC was not associated with CAC in asymptomatic individuals after adjusting for relevant risk factors. No difference in CysC levels was observed between patients with type 1 MI (1.07 mg/L) and patients with normal troponin (with or without prior CAD: 1.14 and 1.01 mg/L, respectively). However, patients with type 2 MI and patient subgroups with elevated troponin but without MI had significantly higher CysC levels (1.24, 1.23 and 1.31 mg/L), even after adjusting for other risk factors. CysC was not associated with CAC in middle-aged asymptomatic individuals from the general population. Furthermore, CysC levels were found to be significantly lower in patients with type 1 MI compared to patients with type 2 MI and patients with elevated troponins but without MI. Thus, in two independent and clinically different populations, no association between CysC and coronary atherosclerotic manifestations could be demonstrated.

Effects of liraglutide on hemodynamic parameters in patients with heart failure

Glucagon-like peptide-1 analogues improve left ventricular function in patients with acute myocardial infarction. This study aimed to evaluate the effects of liraglutide on hemodynamic parameters in patients with heart failure. A total of 78 patients with heart failure were enrolled in this study between August 2014 and November 2015. Of these, 52 patients were randomized 1:1 to receive either liraglutide or placebo for 7 days. Hemodynamic measurements were made using transpulmonary thermodilution and arterial pulse contour analysis. At 7 days, the difference in change of the primary endpoint of cardiac output between the liraglutide group and control group was +1.1 1/min (95% CI +0.1 to +2.2; P < 0.001). Stroke volume was significantly higher in the liraglutide group compared with the control group (difference: +14.6 ml; P < 0.001). The difference in an increase in the left ventricular contractile index after 7 days of treatment was +210.7 mmHg/s (liraglutide versus control, 95% CI−92.1 to +501.5; P < 0.001). Liraglutide causes favorable changes in markers of inflammation and oxidative stress. Glucagon-like peptide-1 may be associated with improvement in left ventricular function in patients with heart failure. These findings need to be confirmed by larger invasive trials.

Effects of Liraglutide on Reperfusion Injury in Patients With ST-Segment-Elevation Myocardial Infarction

BACKGROUND

Liraglutide, a glucagon-like peptide-1 analog, was reported to reduce reperfusion injury in mice. We planned to evaluate the effects of liraglutide on reperfusion injury in patients with acute ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention.

METHODS AND RESULTS

A total of 96 patients with ST-segment-elevation myocardial infarction undergoing emergency primary percutaneous coronary intervention were randomized to receive either subcutaneous liraglutide or placebo. Study treatment was commenced 30 minutes before intervention (1.8 mg) and maintained for 7 days after the procedure (0.6 mg for 2 days, 1.2 mg for 2 days, followed by 1.8 mg for 3 days). The salvage index was calculated from myocardial area at risk, measured during the index admission (35±12 hours), and final infarct size measured at 91±5 days after primary percutaneous coronary intervention by cardiac magnetic resonance. At 3 months, the primary end point, a higher salvage index was found in the liraglutide group than in the placebo group in 77 patients evaluated with cardiac magnetic resonance (0.66±0.14 versus 0.55±0.15; P=0.001). The final infarct size was lower in the liraglutide group than that in the placebo group (15±12 versus 21±15 g; P=0.05). Serum high-sensitivity C-reactive protein level was lower in the liraglutide group (P<0.001). During a 6-month follow-up period, no difference was observed in the incidence of major adverse cardiovascular event. Safety and tolerability were similar among the 2 groups.

CONCLUSIONS

Our study provides evidence that liraglutide improves myocardial salvage and infarct size after ST-segment-elevation myocardial infarction, possibly by reducing reperfusion injury, making it a promising treatment for evaluation in larger trials.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02001363.

Reducing Acute Kidney Injury Due to Contrast Material: How Nurses Can Improve Patient Safety

BACKGROUND

Acute kidney injury due to contrast material occurs in 3% to 15% of the 2 million cardiac catheterizations done in the United States each year.

OBJECTIVE

To reduce acute kidney injury due to contrast material after cardiovascular interventional procedures.

METHODS

Nurse leaders in the Northern New England Cardiovascular Disease Study Group, a 10-center quality improvement consortium in Maine, New Hampshire, and Vermont, formed a nursing task force to reduce acute kidney injury due to contrast material after cardiovascular interventional procedures. Data were prospectively collected January 1, 2007, through June 30, 2012, on consecutive nonemergent patients (n = 20 147) undergoing percutaneous coronary interventions.

RESULTS

Compared with baseline rates, adjusted rates of acute kidney injury among the 10 centers were significantly reduced by 21% and by 28% in patients with baseline estimated glomerular filtration rate less than 60 mL/min per 1.73 m2. Key qualitative system factors associated with improvement included use of multidisciplinary teams, standardized fluid orders, use of an intravenous fluid bolus, patient education about oral hydration, and limiting the volume of contrast material.

CONCLUSIONS

Standardization of evidence-based best practices in nursing care may reduce the incidence of acute kidney injury due to contrast material.

Effects of liraglutide on left ventricular function in patients with non-ST-segment elevation myocardial infarction

The influence of glucagon-like peptide-1 has been studied in several studies in patients with acute myocardial infarction, but not in patients with non-ST-segment elevation myocardial infarction (NSTEMI). We planned to evaluate the effects of liraglutide on left ventricular function in patients with NSTEMI. A total of 90 patients were randomized 1:1 to receive either liraglutide (0.6 mg for 2 days, 1.2 mg for 2 days, followed by 1.8 mg for 3 days) or placebo for 7 days. Eighty-three patients completed the trial. Transthoracic echocardiography was used to assess left ventricular function. At 3 months, the primary endpoint, the difference in the change in left ventricular ejection fraction between the two groups was +4.7 % (liraglutide vs. placebo 95 % CI +0.7 to +9.2 % P = 0.009) under intention-to-treat analysis. The difference in decrease in serum glycosylated hemoglobin levels was -0.2 % (liraglutide vs. placebo 95 % CI -0.1 to -0.3 %; P < 0.001). Inflammation and oxidative stress improved significantly in the liraglutide group compared to the placebo group. Liraglutide could improve left ventricular function in patients with NSTEMI, making it a potential adjuvant therapy for NSTEMI.

Impact of renal function on mean platelet volume and its relationship with coronary artery disease: A single-centre cohort study

BACKGROUND

Mean platelet volume (MPV) has been proposed as a marker of platelet reactivity and cardiovascular disease. Chronic kidney disease (CKD) significantly favors the occurrence of cardiovascular events, by increasing the circulating levels of a wide spectrum of pro-oxidant and pro-thrombotic mediators. However, opposite alterations of platelet function, both enhanced aggregability and increased bleeding diathesis have been reported in these patients, with contrasting results on the effects of renal function on MPV and coronary artery disease, that were assessed in present study.

METHODS

In patients undergoing coronary angiography, MPV and renal function (serum creatinine and estimated Glomerular Filtration Rate, eGFR, by MDRD formula) were assessed at admission. Coronary artery disease (CAD) was defined as a stenosis >50% in at least 1 coronary vessel, while severe CAD as left main or trivessel disease.

RESULTS

Among 3712 patients, 1044 (28.1%) had chronic kidney disease. CKD was related with age, female gender, diabetes and glycemic control, history of myocardial infarction, cerebrovascular accidents, coronary artery bypass grafting and left ventricular dysfunction or arrhythmias as indication to angiography, therapy with angiotensin-receptor blockers, nitrates, diuretics and calcium-antagonists, but lower rate of smoking, lower fibrinogen levels, haemoglobin, total and HDL cholesterol (p<0.001, respectively). CKD patients displayed increased severity and complexity of CAD (p<0.001) and significantly larger platelet volume (p<0.001), with CKD resulting as independent predictor of MPV above the median (≥10.85fl; Adjusted OR[95%CI]=1.56[1.23,1.99], p=0.002). Moreover, in the 1044 patients with renal failure, higher platelet volume (above the median value; ≥10.85fl) was associated with age (p=0.05), haemoglobin levels and platelet count (p<0.001), but not to a higher prevalence or extent of coronary artery disease (CAD: adjusted OR[95%CI]=0.80[0.58-1.09], p=0.16; severe CAD, adjusted OR[95%CI]=1.07[0.81-1.41], p=0.65).

CONCLUSIONS

Higher values of MPV are observed among patients with chronic kidney disease, inversely relating to eGFR. However, larger platelet size does not contribute to explain the increased severity of coronary artery disease observed among these patients.

Effects of liraglutide on no-reflow in patients with acute ST-segment elevation myocardial infarction

BACKGROUND

The 'no-reflow' phenomenon after a percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI) is a strong predictor of both short- and long-term mortality. Glucagon-like peptide-1 (GLP-1) exerts a cardioprotective effect during ischemia reperfusion injury. We planned to evaluate the effects of liraglutide on myocardial no-reflow after PCI for STEMI.

METHODS

A total of 284 patients with STEMI undergoing PCI were enrolled in this study between September 2013 and March 2015. Of these, 210 patients were randomized 1:1 to receive either liraglutide or placebo 30 min before PCI (1.8 mg).

RESULTS

The primary end point, the prevalence of no-reflow, was significantly lower in the liraglutide group than in the control group (5% vs. 15%, P=0.01). Administration of liraglutide was consistently identified as a significant determinant for no-reflow ratio. There was a significant decrease in serum high-sensitivity C-reactive protein levels at 6-hour reperfusion in the liraglutide group compared to the control group (0.87 ± 0.09 mg/dL vs. 0.96 ± 0.10mg/dL, P<0.001). During a 3-month follow-up period, no difference was observed in the incidence of major adverse cardiovascular event.

CONCLUSIONS

Liraglutide may be associated with less no-reflow in STEMI, which should be confirmed by larger-scale trials.

Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na⁺ channel and Na⁺ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na⁺/Ca²⁺ exchange (NCX) and Na⁺/K⁺-ATPase (NKA). While the relevance of Ca²⁺ homeostasis in cardiac function has been extensively investigated, the role of Na⁺ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na⁺ content have multiple effects on the heart by influencing intracellular Ca²⁺ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na⁺ homeostasis. Among the proteins that accomplish this task are the Na⁺/Ca²⁺ exchanger (NCX) and the Na⁺/K⁺ pump (NKA). By transporting three Na⁺ ions into the cytoplasm in exchange for one Ca²⁺ moved out, NCX is one of the main Na⁺ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na⁺ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na⁺ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na⁺ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na⁺/Ca²⁺ exchanger (NCX1) and Na⁺/K⁺ pump and the controversies that still persist in the field.

Effects of liraglutide on left ventricular function in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND

Several studies have shown that exenatide protects against ischemia-reperfusion injury and improves cardiac function in patients with acute ST-segment elevation myocardial infarction (STEMI). The effects of liraglutide, a glucagon-like peptide-1 analogue, on STEMI patients remain unclear. We planned to evaluate the effects of liraglutide on left ventricular function after primary percutaneous coronary intervention for STEMI.

METHODS

A total of 92 patients were randomized 1:1 to receive either liraglutide or placebo for 7 days. Study treatment was commenced 30 minutes before intervention (1.8 mg) and maintained for 7 days after the procedure (0.6 mg for 2 days, 1.2 mg for 2 days, followed by 1.8 mg for 3 days). Eighty-five patients completed the trial. Transthoracic echocardiography was used to assess left ventricular function.

RESULTS

At 3 months, the primary end point, a difference in change of left ventricular ejection fraction between the two groups was +4.1% (95% CI +1.1% to +6.9%) (P < .001). There was a tendency for a lower rate of no-reflow in liraglutide group that did not reach statistical significance (7% vs control group 15%, P = .20). Liraglutide could significantly improve stress hyperglycemia (P < .05). In addition, liraglutide elicited favorable changes in markers of inflammation and endothelial function.

CONCLUSION

A short 7-day course of liraglutide in STEMI patients treated with primary percutaneous coronary intervention is associated with mild improvement in left ventricular ejection fraction at 3 months.

The role of cardiotonic steroids in the pathogenesis of cardiomyopathy in chronic kidney disease

Cardiotonic steroids (CTS) are a new class of hormones that circulate in the blood and are divided into two distinct groups, cardenolides, such as ouabain and digoxin, and bufadienolides, such as marinobufagenin, telocinobufagin and bufalin. They have the ability to bind and inhibit the ubiquitous transport enzyme sodium potassium pump, thus regulating intracellular Na(+) concentration in every living cell. Although digoxin has been prescribed to heart failure patients for at least 200 years, the realization that CTS are endogenously produced has intensified research into their physiological and pathophysiological roles. Over the last two decades, substantial evidence has accumulated demonstrating the effects of endogenously synthesised CTS on the kidneys, vasculature and the heart. In this review, the current state of art and the controversies surrounding the manner in which CTS mediate their pathophysiological effects are discussed. Several potential therapeutic strategies have emerged as a result of our increased understanding of the role CTS play in health and disease.

Reducing contrast-induced acute kidney injury using a regional multicenter quality improvement intervention

BACKGROUND

Contrast-induced acute kidney injury (CI-AKI) is associated with increased morbidity and mortality after percutaneous coronary interventions and is a patient safety objective of the National Quality Forum. However, no formal quality improvement program to prevent CI-AKI has been conducted. Therefore, we sought to determine whether a 6-year regional multicenter quality improvement intervention could reduce CI-AKI after percutaneous coronary interventions.

METHODS AND RESULTS

We conducted a prospective multicenter quality improvement study to prevent CI-AKI (serum creatinine increase ≥0.3 mg/dL within 48 hours or ≥50% during hospitalization) among 21 067 nonemergent patients undergoing percutaneous coronary interventions at 10 hospitals between 2007 and 2012. Six intervention hospitals participated in the quality improvement intervention. Two hospitals with significantly lower baseline rates of CI-AKI, which served as benchmark sites and were used to develop the intervention, and 2 hospitals not receiving the intervention were used as controls. Using time series analysis and multilevel poisson regression clustering to the hospital level, we calculated adjusted risk ratios for CI-AKI comparing the intervention period to baseline. Adjusted rates of CI-AKI were significantly reduced in hospitals receiving the intervention by 21% (risk ratio, 0.79; 95% confidence interval: 0.67-0.93; P=0.005) for all patients and by 28% in patients with baseline estimated glomerular filtration rate <60 mL/min per 1.73 m(2) (risk ratio, 0.72; 95% confidence interval: 0.56-0.91; P=0.007). Benchmark hospitals had no significant changes in CI-AKI. Key qualitative system factors associated with improvement included multidisciplinary teams, limiting contrast volume, standardized fluid orders, intravenous fluid bolus, and patient education about oral hydration.

CONCLUSIONS

Simple cost-effective quality improvement interventions can prevent ≤1 in 5 CI-AKI events in patients with undergoing nonemergent percutaneous coronary interventions.

Sex differences in risk factors for retinopathy in non-diabetic men and women: the Tromsø Eye Study

PURPOSE

  To determine the prevalence and risk factors for retinopathy in a nondiabetic population.

METHODS

  The study population included 5869 participants without diabetes aged 38-87 years from the Tromsø Eye Study, a substudy of the population-based Tromsø Study in Norway. Retinal images from both eyes were graded for retinopathy. We collected data on risk factors from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. The cross-sectional relationship between potential risk factors and retinopathy was assessed using logistic regression analysis.

RESULTS

  The overall prevalence of retinopathy was 14.8%. Men had a higher prevalence of retinopathy compared with women (15.9% versus 14.0%, p=0.04). In men, retinopathy was associated with hypertension (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.24-2.04) and HbA1c (OR per %, 1.41; 95% CI, 1.01-1.96). In women, retinopathy was associated with age (OR per 10 years, 1.32; 95% CI, 1.14-1.52), log-transformed urinary albumin excretion (OR per log unit, 1.46; 95% CI, 1.14-1.87) and hypertension (OR, 1.36; 95% CI, 1.08-1.71). In women, retinopathy was associated with very low levels of urinary albumin excretion (urinary albumin/creatinine ratio >0.43 mg/mmol).

CONCLUSION

  This study confirms results from previous studies on the strong association between blood pressure and retinopathy. A novel finding is the sex differences in risk factors for retinopathy, suggesting a sex difference in the pathogenesis leading to retinopathy.

Role of thyroid hormones and mir-208 in myocardial remodeling in 5/6 nephrectomized rats

BACKGROUND AND AIMS

Thyroid hormones exert important effects on heart remodeling through mir-208. The process may have a role in myocardial changes in chronic kidney disease where thyroid abnormalities are common. In this study the effect of T4 supplementation on left ventricle (LV) remodeling in 5/6 nephrectomized rats (5/6Nx) was analyzed.

METHODS

5/6Nx rats and 5/6Nx under T4 supplementation (5/6Nx + T4) were compared with control (C) and thyroidectomized (Tx) rats. After 8 weeks of follow-up, LV was analyzed for α-MHC, β-MHC, TGF-β, and mir-208 expression, hydroxyproline content, and myocardial fibrosis. Serum collagenase activity was also analyzed.

RESULTS

Heart weight increased in 5/6Nx rats compared to C, which was prevented with T4 supplementation (C, 1.5 ± 0.04; 5/6Nx, 1.8 ± 0.09; 5/6Nx + T4, 1.6 ± 0.07 g, p <0.05). The same pattern was seen for LV wall thickness, hydroxyproline content, LV fibrosis, and mRNA TGF-β expression (C, 0.47 ± 0.17; 5/6Nx, 10.55 ± 3.4; 5/6Nx + T4, 3.01 ± 0.52, p <0.01). Tx rats had reduction in heart weight, increased LV wall thickness, and fibrosis. Collagenase activity did not change in any group. mRNA expression of α-, β-MHC, and TGF-β increased in 5/6Nx in comparison to C and 5/6Nx + T4. Expression of mir-208 decreased in 5/6Nx groups, and levels were restored with T4 supplementation (4.21 ± 0.28, 3.39 ± 0.29, and 4.26 ± 0.37 RU, respectively, p <0.01).

CONCLUSIONS

Decreased plasma level of thyroid hormones or sensitivity at tissue level observed in chronic kidney disease induced by 5/6Nx has an important effect in heart remodeling processes, some of it related or mediated by mir-208 and TGF-β expression in the heart.

Decreased renal function is an independent predictor of severity of coronary artery disease: an application of Gensini score

Coronary artery disease (CAD) is the leading cause of death in patients with chronic kidney disease (CKD).Although many studies have shown a higher prevalence of CAD among these patients, the association between the spectrum of renal dysfunction and severity of CAD remains unclear. In this study, we investigate the association between renal function and the severity of CAD. We retrospectively reviewed the medical records of 1,192 patients who underwent elective coronary angiography (CAG). The severity of CAD was evaluated by Gensini score according to the degree of luminal narrowing and location(s) of obstruction in the involved main coronary artery. In all patients, the estimated glomerular filtration rate (eGFR) was independently associated with Gensini score (β=-0.27, P < 0.001) in addition to diabetes mellitus (β=0.07, P = 0.02), hypertension (β=0.12, P < 0.001), low density lipoprotein (LDL)-cholesterol (β=0.08, P = 0.003), and hemoglobin (β=-0.07, P = 0.03) after controlling for other confounding factors. The result of this study demonstrates that decreased renal function is associated not only with the prevalence, but also the severity, of CAD.

Impact of occult renal impairment on early and late outcomes following coronary artery bypass grafting

OBJECTIVES

High serum creatinine is considered an independent risk factor for poor outcomes following coronary artery bypass grafting (CABG). However, the impact of occult renal impairment (ORI), defined as an impaired glomerular filtration rate (GFR) with a normal serum creatinine (SCr) level, remains unclear. Thus, we sought to investigate the impact of ORI on outcomes after CABG.

METHODS

Among patients undergoing their first percutaneous coronary intervention (PCI) or CABG enrolled in the CREDO-Kyoto Registry (a registry of first-time PCI and CABG patients in Japan), 1842 patients with normal SCr levels undergoing CABG were enrolled in the study. Patients were divided into two groups based on preoperative estimated GFR calculated by the Cockcroft-Gault equation: 1339 patients with estimated GFR of ≥ 60 ml/min/1.73 m(2) (normal group) and 503 with estimated GFR of <60 ml/min/1.73 m(2) (ORI group).

RESULTS

Preoperative estimated GFR differed between the groups (51.3 ± 6.6 vs 85.8 ± 23.0 ml/min/1.73 m(2), P < 0.01). ORI was associated with high in-hospital mortality (3.2 vs 1.0%, P < 0.01) and need for dialysis (2.0 vs 0.2%, P < 0.01). In terms of long-term outcomes, ORI was associated with high mortality compared with the normal (hazard ratio [95% confidence interval]: 1.72 [1.16-2.54], P < 0.01) and high incidence of composite cardiovascular events (death, stroke or myocardial infarction: 1.53 [1.16-2.02], P < 0.01).

CONCLUSIONS

ORI was an independent risk factor for early and late death as well as cardiovascular events in patients undergoing CABG with normal SCr levels. A more accurate evaluation of renal function through a combination of SCr and estimated GFR is needed in patients with normal SCr levels.

Selected nutraceutic screening by therapeutic effects on doxorubicin-induced chronic kidney disease

SCOPE

The number of patients with chronic kidney disease (CKD) are increasing. Interventions such as controlling hypertension and specific pharmacologic options are recommended. Some nutraceutics may have benefits in this regard.

METHODS AND RESULTS

Naringenin (a flavanon), catechin (a flavanol), and quercetin (a flavonol) and rutin (a flavonol rutinoside) were tried on CKD in a Sprague Dawley rat model. Results indicated quercetin to be the most effective therapeutic candidate with respect to renal edema, hypertension, serum creatinine, hematocrit, cardiopathy, aorta calcification, glomerular amyloidosis, erythrocyte depletion in bone marrow, collagen deposition, expressions of TNF-α, cleaved caspase-3, IκBα, PPARα, and serum insulin. But quercetin was only partially effective in restoring glomerular filtration rate, albuminuria, serum cholesterol, triglyceride, blood urea nitrogen (BUN), uric acid, malondialdehyde, superoxide dismutase; urinary BUN and urinary creatinine. As for signaling, quercetin was completely effective in alleviating the cleaved caspase-3, being only partially effective in suppressing Bax and Bad, restoring Bcl-2, and rescuing DNA damage.

CONCLUSION

The CKD status cannot to be ameliorated by naringenin, rutin, and catechin. Comparatively, quercetin may be a better therapeutic candidate.

Diagnosis of cardiovascular disease in patients with chronic kidney disease

The major forms of cardiovascular disease including coronary atherosclerosis, valvular disease, myocardial dysfunction, and arrhythmias are observed either alone or in combination in a large fraction of patients with chronic kidney disease (CKD). As CKD progresses, these cardiovascular conditions become more prevalent and severe. The clinical implications of combined heart and kidney disease include challenges in diagnosis and management. In addition, the terminal events in CKD commonly involve one of these four domains of cardiovascular disease. This paper will explore the issue of early diagnosis of heart disease in patients with CKD with the major goal being early intervention to lessen the impact of this comorbidity.

How do centres begin the process to prevent contrast-induced acute kidney injury: a report from a new regional collaborative

OBJECTIVES

This study evaluates the variation in practice patterns associated with contrast-induced acute kidney injury (CI-AKI) and identifies clinical practices that have been associated with a reduction in CI-AKI. Background CI-AKI is recognised as a complication of invasive cardiovascular procedures and is associated with cardiovascular events, prolonged hospitalisation, end-stage renal disease, and all-cause mortality. Reducing the risk of CI-AKI is a patient safety objective set by the National Quality Forum.

METHODS

This study prospectively collected quantitative and qualitative data from 10 centres, which participate in the Northern New England Cardiovascular Disease Study Group PCI Registry. Quantitative data were collected from the PCI Registry. Qualitative data were obtained through clinical team meetings to map care processes related to CI-AKI and focus groups to understand attitudes towards CI-AKI prophylaxis. Fixed and random effects modelling were conducted to test the differences across centres.

RESULTS

Significant variation in rates of CI-AKI were found across 10 medical centres. Both fixed effects and mixed effects logistic regression demonstrated significant variability across centres, even after adjustment for baseline covariates (p<0.001 for both modelling approaches). Patterns were found in reported processes and clinical leadership that were attributable to centres with lower rates of CI-AKI. These included reducing nil by mouth (NPO) time to 4 h prior to case, and standardising volume administration protocols in combination with administering three to four high doses of N-acetylcysteine (1200 mg) for each patient.

CONCLUSIONS

These data suggest that clinical leadership and institution-focused efforts to standardise preventive practices can help reduce the incidence of CI-AKI.

Incidence and predictors of major complications from contemporary catheter ablation to treat cardiac arrhythmias

BACKGROUND

Updated understanding of the risks of catheter ablation is important because techniques have evolved for procedures treating non-life-threatening as well as potentially lethal arrhythmias.

OBJECTIVE

This prospective study sought to assess the incidence and predictors of major complications from contemporary catheter ablation procedures at a high-volume center.

METHODS

Over a 2-year period, 1,676 consecutive ablation procedures were prospectively evaluated for major complications throughout 30 days postprocedure. Predictors of major complications were determined in a multivariate analysis adjusted for demographics, clinical variables, ablation type, and procedural factors.

RESULTS

Rates of major complications differed between procedure types, ranging from 0.8% for supraventricular tachycardia, 3.4% for idiopathic ventricular tachycardia (VT), 5.2% for atrial fibrillation (AF), and 6.0% for VT associated with structural heart disease (SHD). Ablation type (ablation for AF [odds ratio (OR) 5.53, 95% confidence interval (CI) 1.81 to 16.83], for VT with SHD [OR 8.61, 95% CI 2.37 to 31.31], or for idiopathic VT [OR 5.93, 95% CI 1.40 to 25.05] all referenced to supraventricular tachycardia ablation), and serum creatinine level >1.5 mg/dl (OR 2.48, 95% CI 1.07 to 5.76) were associated with increased adjusted risk of major complications, whereas age, gender, body mass index, international normalized ratio level, hypertension, coronary artery disease, diabetes, and prior cerebrovascular accident were not associated with increased risk.

CONCLUSION

In a large cohort of contemporary catheter ablation, major complication rates ranged between 0.8% and 6.0% depending on the ablation procedure performed. Aside from ablation type, renal insufficiency was the only independent predictor of a major complication.

Understanding the effects of chronic kidney disease on cardiovascular risk: are there lessons to be learnt from healthy kidney donors?

Chronic kidney disease (CKD) is now a recognized global public health problem. It is highly prevalent and strongly associated with hypertension and cardiovascular disease (CVD); far more patients with a glomerular filtration rate below 60 ml min(-1) per 1.73 m(2) will die from cardiovascular causes than progress to end-stage renal disease. A better understanding of the complex mechanisms underlying the development of CVD among CKD patients is required if we are to begin devising therapy to prevent or reverse this process. Observational studies of CVD in CKD are difficult to interpret because renal impairment is almost always accompanied by confounding factors. These include the underlying disease process itself (for example, diabetes mellitus and systemic vasculitis) and the complications of CKD, such as hypertension, anaemia and inflammation. Kidney donors provide an ideal opportunity to study healthy subjects without manifest vascular disease who experience an acute change from having normal to modestly impaired renal function at the time of uninephrectomy. Prospectively examining the cardiovascular consequences of uninephrectomy using donors as a model of CKD may provide useful insight into the pathophysiology of CVD in CKD and, therefore, into how the CVD risk associated with renal impairment might eventually be reduced.

The relationship between chronic kidney disease and SYNTAX score

Chronic kidney disease (CKD) is associated with increased risk of cardiovascular disease and death. We evaluated the association between CKD and severity of coronary artery stenosis by calculating SYNTAX Score in patients with left main coronary artery and/or 3-vessel coronary artery disease. Coronary angiograms of 217 patients were assessed. Chronic kidney disease was staged using the estimated glomerular filtration rate (eGFR, mL/min per 1.73 m(2)) prior to coronary angiography. Patients were divided into 5 groups according to the National Kidney Foundation Kidney Disease Outcome Quality Initiative (NKF KDOQI) Clinical Practice Guidelines (14). Patients with eGFR >90 mL/min per 1.73 m(2) (group 1), patients with eGFR 60 to 89 mL/min per 1.73 m(2) (group 2), patients with eGFR 30 to 59 mL/min per 1.73 m(2) (group 3), patients with eGFR >15 to < 30 per 1.73 m(2) and dialysis patients with eGFR < 15 per 1.73 m(2) were combined as group 4. The risk of significant lesion complexity increased progressively with decreasing kidney function (P = .001). Estimated glomerular filtration rate was a strong predictor of higher SYNTAX Score.

Increased mortality among survivors of myocardial infarction with kidney dysfunction: the contribution of gaps in the use of guideline-based therapies

Background

We assessed the degree to which differences in guideline-based medical therapy for acute myocardial infarction (AMI) contribute to the higher mortality associated with kidney disease.

Methods

In the PREMIER registry, we evaluated patients from 19 US centers surviving AMI. Cox regression evaluated the association between estimated glomerular filtration rate (GFR) and time to death over two years, adjusting for demographic and clinical variables. The contribution of variation in guideline-based medical therapy to differences in mortality was then assessed by evaluating the incremental change in the hazard ratios after further adjustment for therapy.

Results

Of 2426 patients, 26% had GFR ≥ 90, 44% had GFR = 60- < 90, 22% had GFR = 30- < 60, and 8% had GFR < 30 ml/min/1.73 m². Greater degrees of renal dysfunction were associated with greater 2-year mortality and lower rates of guideline-based therapy among eligible patients. For patients with severely decreased GFR, adjustment for differences in guideline-based therapy did not significantly attenuate the relationship with mortality (HR 3.82, 95% CI 2.39–6.11 partially adjusted; HR = 3.90, 95% CI 2.42–6.28 after adjustment for treatment differences).

Conclusion

Higher mortality associated with reduced GFR after AMI is not accounted for by differences in treatment factors, underscoring the need for novel therapies specifically targeting the pathophysiological abnormalities associated with kidney dysfunction to improve survival.

Evaluation of urine proteome pattern analysis for its potential to reflect coronary artery atherosclerosis in symptomatic patients

Coronary artery disease (CAD) is a major cause of mortality and morbidity. Noninvasive proteome analysis could guide clinical evaluation and early/preventive treatment. Under routine clinical conditions, urine of 67 patients presenting with symptoms suspicious for CAD were analyzed by capillary electrophoresis directly coupled with mass spectrometry (CE-MS). All patients were subjected to coronary angiography and either assigned to a CAD or non-CAD group. A training set of 29 patients was used to establish CAD and non-CAD-associated proteome patterns of plasma as well as urine. Significant discriminatory power was achieved in urine but not in plasma. Therefore, urine proteomic analysis of further 38 patients was performed in a blinded study. A combination of 17 urinary polypeptides allowed separation of both groups in the test set with a sensitivity of 81%, a specificity of 92%, and an accuracy of 84%. Sequencing of urinary marker peptides identified fragments of collagen alpha1 (I and III), which we furthermore demonstrated to be expressed in atherosclerotic plaques of human aorta. In conclusion, specific CE-MS polypeptide patterns in urine were associated with significant CAD in patients with angina-typical symptoms. These promising findings need to be further evaluated in regard to reliability of a urine-based screening method with the potential of improving the diagnostic approaches for CAD.

Pulse pressure and presence of coronary artery calcification

BACKGROUND

Coronary calcification (CAC) is found in early stages of CKD. Pulse pressure (PP) predicts CAC in dialysis patients. This study evaluates the accuracy of PP in predicting CAC in patients not yet on dialysis (CKD patients).

METHODS

CKD patients (n = 388) underwent coronary calcium score (CAC score) and abdominal x-ray (n = 128) for estimating aorta calcification (AAC). Biochemistry and PP were measured every 3 and 6 months in patients with stage 4 to 5 and 2 to 3 CKD, respectively. The accuracy of PP and AAC was assessed by receiver operating characteristics analysis.

RESULTS

PP correlated with CAC score in the whole cohort and in patients with stages 2 to 3 and stages 4 to 5 CKD. PP >60 mmHg predicted CAC score >0 (OR: 2.14; P < 0.001), > or =100 (OR: 2.92; P < 0.001), > or =400 (OR: 6.17; P < 0.001) after multivariable adjustment. Area under the curve (AUC) was 0.626 for CAC score >0, 0.676 for score >100, and 0.746 for score >400. PP >60 mmHg reduced the rate of event-free survival. AAC was found in 58% of patients and correlated with CAC score. AUC was 0.628 for CAC score >0, 0.652 for score >100, 0.831 for score >400.

CONCLUSION

PP may identify CKD patients with subclinical CAC who need further evaluation. Accuracy of PP and AAC is nearly similar in predicting CAC. High PP indicates vessel wall alterations leading to adverse outcome.

Interaction of gender and age on post cardiac catheterization contrast-induced acute kidney injury

The purpose of this study was to determine the relative impact of gender and age on the development of contrast-induced acute kidney injury (CIAKI) after cardiac catheterization. CIAKI is a recognized complication of coronary angiography, but the relative impact of age strata and gender is not well understood. We prospectively enrolled 21,489 consecutive patients undergoing coronary angiography and stratified patients by age and gender into 4 age categories (<50, 51 to 64, 65 to 79, and >80 years). Of those 21,489 patients, 13,127 were included in the study. Men and women were compared within each age category for the development of CIAKI in the period after angiography. The incidence of postprocedural CIAKI and mortality rates among groups were compared. Rates of postcatheterization CIAKI were higher for women compared with men in the 65- to 79-year-old (14.5% vs 11.0%, p <0.001) and >80-year-old (18.7% vs 15.1%, p = 0.048) groups, but no differences were seen in the younger cohorts. In conclusion, geriatric women are at greatest risk for the development of CIAKI after angiography.

Transient and persistent renal dysfunction are predictors of survival after percutaneous coronary intervention: insights from the Dartmouth Dynamic Registry

OBJECTIVES

We sought to determine if transient and persistent elevations in creatinine following percutaneous coronary intervention (PCI) resulted in poor survival.

BACKGROUND

Limited survival data exist that defines the natural survival history of transient and persistent renal dysfunction following interventional PCI cases.

METHODS

Data were collected prospectively on 7,856 consecutive patients undergoing PCI from January 1, 2000 to July 31, 2006. Ninety-three patients were excluded due to pre-PCI dialysis. Patients were stratified into three categories of renal dysfunction: no renal dysfunction from baseline (<0.5 mg/dL increase in creatinine within 48 hr of the procedure), transient renal dysfunction (> or =0.5 mg/dL increase in creatinine within 48 hr with return to normal within 2 weeks), and persistent renal dysfunction (> or =0.5 mg/dL increase in creatinine without returning to normal within 2 weeks of the procedure). Mortality was determined by comparing with the Social Security Death Master File.

RESULTS

Median survival was 3.2 years (mean 3.4). Renal dysfunction occurred in 250 patients (0.5 mg/dL increase in creatinine). Survival was significantly different between patients at 1, 3.2, and 7.5 years (P-value < 0.001): no renal dysfunction (95%, 88%, 75%), with transient (61%, 42%, 0%), and with persistent (58%, 44%, 36%) renal dysfunction. Patients with transient or persistent renal dysfunction had a twofold-threefold increased risk of 7.5-year mortality compared with patients with no renal dysfunction.

CONCLUSIONS

Both transient and persistent postprocedural renal dysfunction are prognostically significant for mortality during extended follow-up. Renal dysfunction should be closely monitored before and after PCI.

Impact of chronic kidney disease on postinfarction inflammation, oxidative stress, and left ventricular remodeling

BACKGROUND

Patients with chronic kidney disease (CKD) have poor clinical outcomes after myocardial infarction (MI). However, the precise mechanisms are unclear. We sought to determine the prognostic significance of CKD in patients with MI in relation to left ventricular (LV) remodeling.

METHODS AND RESULTS

We examined 120 consecutive patients with a reperfused first anterior ST-elevation MI. Patients were divided into 2 groups according to the presence or absence of CKD, defined as estimated glomerular filtration rates <60 mL x min x 1.73 m2. Patients with CKD had a higher incidence of in-hospital cardiac death and readmission for heart failure during follow-up, in association with a greater LV volume and lower LV ejection fraction 2 weeks after MI compared with those without CKD. Cox proportional hazards model analysis revealed that CKD was an independent predictor of major adverse cardiac events (hazard ratio=3.13, P=.001). Plasma interleukin-6 on admission, and peak serum C-reactive protein, and malondialdehyde-modified low-density lipoprotein levels during convalescence, were higher in patients with CKD than in those without.

CONCLUSIONS

Patients with CKD had poorer clinical outcomes and accelerated infarct expansion in association with enhanced inflammation and oxidative stress, as compared with non-CKD patients, suggesting a major impact of CKD in the development of LV remodeling after MI.

Risk prediction in chest pain patients by biochemical markers including estimates of renal function

BACKGROUND

Early risk stratification of patients with chest pain may be improved by combining cardiac Troponin I (cTnI) results and ECG findings with markers of left-ventricular dysfunction, inflammation or renal function.

METHODS

Serial measurements of cTnI were prospectively performed in 452 chest pain patients with a non-diagnostic ECG for AMI and admitted to the coronary care unit. NT-pro BNP, CRP, cystatin C and creatinine-clearance were retrospectively analyzed in admission samples. The prognostic value of these markers alone and in different combinations together with ECG findings was evaluated by multivariate logistic regression models.

RESULTS

During follow-up, 14 deaths and 21 myocardial (re)-infarctions occurred. Independent predictors for the combined endpoint of death or (re)-infarction were peak cTnI >or=0.1 microg/L within 24 h (OR 3.9; 95% confidence interval [CI]1.5-10.4), cystatin C >or=1.28 mg/L (OR 5.6; 95% CI 1.9-16.3) and NT-pro BNP >or=550 ng/L (OR 2.7; 95% CI 1.0-7.3). At 2 h from admission, a combination of cTnI >or=0.1 microg/L, an abnormal ECG and NT-pro BNP or cystatin C as a third variable resulted in a similar stratification of patients to different risk groups.

CONCLUSION

cTnI, NT-pro BNP and cystatin C are strong risk predictors in patients with chest pain. For pragmatic reasons, a combination of cTnI >or=0.1 microg/L, ECG findings and a marker of renal function, preferably cystatin C, appears to be most appropriate for early risk stratification of these patients.

Estimated glomerular filtration rate, inflammation, and cardiovascular events after an acute coronary syndrome

Both renal dysfunction and elevated levels of high-sensitivity C-reactive protein (CRP) are associated with a higher risk of cardiovascular (CV) outcomes. However, it remains to be established whether the prognostic value of impaired estimated glomerular filtration rate (GFR) remains after accounting for markers of inflammation.

METHODS AND RESULTS

Glomerular filtration rate was estimated using the Modification of Diet in Renal Disease equation in 4178 patients with non-ST or ST-elevation acute coronary syndromes, participating in the A to Z trial. The mean estimated GFR was 68 mL/min, with a median baseline CRP of 20.2 mg/L. Both an estimated GFR <60 mL/min (HR 2.13, 95% CI 1.7-2.6) and a CRP in the fourth quartile (HR 1.7, 95% CI 1.4-2.2) were strong univariate predictors of a CV event (composite of CV death, recurrent myocardial infarction, heart failure, or stroke). After adjusting for baseline CRP, GFR <60 mL/min remained a strong multivariate predictor for CV death (HR 1.82, 95% CI 1.1-2.97). Randomization to high-dose statin therapy was associated with a reduction in the CV composite (adjusted HR 0.69, 95% CI 0.5-0.95) irrespective of baseline renal function.

CONCLUSIONS

In a population of patients without overt renal disease, moderate reductions in estimated GFR remain an important prognostic marker. This increased CV hazard associated with an estimated GFR <60 mL/min is independent and additive to markers of inflammation.

Serious renal dysfunction after percutaneous coronary interventions can be predicted

BACKGROUND

A prediction rule for determining the post-percutaneous coronary intervention (PCI) risk of developing contrast-induced nephropathy (> or = 25% or > or = 0.5 mg/dL increase in creatinine) has been reported. However, little work has been done on predicting pre-PCI patient-specific risk for developing more serious renal dysfunction (SRD; new dialysis, > or = 2.0 mg/dL absolute increase in creatinine, or a > or = 50% increase in creatinine). We hypothesized that preprocedural patient characteristics could be used to predict the risk of post-PCI SRD.

METHODS

Data were prospectively collected on a consecutive series of 11141 patients undergoing PCI without dialysis in northern New England from 2003 to 2005. Multivariate logistic regression model was used to identify the combination of patient characteristics most predictive of developing post-PCI SRD. The ability of the model to discriminate was quantified using a bootstrap validated C-Index (area under the receiver operating characteristic [ROC] curve). Its calibration was tested with a Hosmer-Lemeshow statistic. The model was validated on PCI procedures in 2006.

RESULTS

Serious renal dysfunction occurred in 0.74% of patients (83/11141) with an associated inhospital mortality of 19.3% versus 0.9% in those without SRD. The model discriminated well between patients who did and did not develop SRD after PCI (ROC 0.87, 95% CI 0.82-0.91). Preprocedural creatinine (37%), congestive heart failure (24%), and diabetes (15%) accounted for 76% of the predictive ability of the model. The other factors contributed 24%: urgent and emergent priority (10%), preprocedural intra-aortic balloon pump use (8%), age > or = 80 years (5%), and female sex (1%). Validation of the model was successful with ROC: 0.84 (95% CI 0.80-0.89).

CONCLUSIONS

Although infrequent, the occurrence of SRD after PCI is associated with a very high inhospital mortality. We developed and validated a robust clinical prediction rule to determine which patients are at high risk for SRD. Use of this model may help physicians perform targeted interventions to reduce this risk.

Multivariable prediction of renal insufficiency developing after cardiac surgery

BACKGROUND

Renal insufficiency after coronary artery bypass graft (CABG) surgery is associated with increased short-term and long-term mortality. We hypothesized that preoperative patient characteristics could be used to predict the patient-specific risk of developing postoperative renal insufficiency.

METHODS AND RESULTS

Data were prospectively collected on 11,301 patients in northern New England who underwent isolated CABG surgery between 2001 and 2005. Based on National Kidney Foundation definitions, moderate renal insufficiency was defined as a GFR <60 mL/min/1.73 m2 and severe renal insufficiency as a GFR <30. Patients with at least moderate renal insufficiency at baseline were eliminated from the analysis, leaving 8363 patients who became our study cohort. A prediction model was developed to identify variables that best predicted the risk of developing severe renal insufficiency using multiple logistic regression, and the predictive ability of the model quantified using a bootstrap validated C-Index (Area Under ROC) and Hosmer-Lemeshow statistic. Three percent of the patients with normal renal function before CABG surgery developed severe renal insufficiency (229/8363). In a multivariable model the preoperative patient characteristics most strongly associated with postoperative severe renal insufficiency included: age, gender, white blood cell count >12,000, prior CABG, congestive heart failure, peripheral vascular disease, diabetes, hypertension, and preoperative intraaortic balloon pump. The predictive model was significant with chi2 150.8, probability value <0.0001. The model discriminated well, ROC 0.72 (95%CI: 0.68 to 0.75). The model was well calibrated according to the Hosmer-Lemeshow test.

CONCLUSIONS

We developed a robust prediction rule to assist clinicians in identifying patients with normal, or near normal, preoperative renal function who are at high risk of developing severe renal insufficiency. Physicians may be able to take steps to limit this adverse outcome and its associated increase in morbidity and mortality.

Renal and vascular protective effects of cilnidipine in patients with essential hypertension

OBJECTIVES

Cilnidipine is a calcium channel blocker that blocks both L and N-type calcium channels. L/N-type calcium channel blockers exhibit sympatholytic action and a renal protective effect via dilation of afferent and efferent arterioles of the renal glomerulus, and afford more potent protection against hypertension-related organ damage than L-type calcium channel blockers. Few studies, however, have directly compared the organ protective effects of L-type calcium channel blocker monotherapy and L/N-type calcium channel blocker monotherapy. This study compares the effects on renal and vascular endothelial functions and arterial stiffness of monotherapy regimens of amlodipine, an L-type calcium antagonist, and cilnidipine, in patients with essential hypertension.

METHODS

Fifty patients with untreated essential hypertension were randomized to receive 5 mg of amlodipine (n = 25) or 10 mg of cilnidipine (n = 25) once daily in the morning for 24 weeks. The patients were evaluated before and after the therapy to assess changes in renal function, flow-mediated vasodilation (a parameter of vascular endothelial function), and brachial-ankle pulse wave velocity (a parameter of arterial stiffness).

RESULTS

Before treatment, the above parameters showed no significant differences between groups. After treatment, urinary albumin excretion was decreased significantly in the cilnidipine group compared with the amlodipine group, and the decrease of brachial-ankle pulse wave velocity was significantly larger in the cilnidipine group than in the amlodipine group.

CONCLUSIONS

These results suggest that cilnidipine is more effective than amlodipine at improving renal function and arterial stiffness in patients with essential hypertension.

Percutaneous coronary intervention versus coronary artery bypass grafting in patients with coronary artery disease and diabetic nephropathy: a single center experience

BACKGROUND

Patients with diabetic nephropathy (DN) and coronary artery disease (CAD) represent a subset of patients with high cardiovascular morbidity and mortality. The optimal revascularization strategy using either percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) remains controversial. The purpose of this study was to compare the clinical outcomes of PCI to CABG in DN patients with CAD.

METHODS

The clinical and angiographic records of DN patients with CAD who underwent either CABG (n=52) or PCI (n=48) were retrospectively analyzed.

RESULTS

The baseline characteristics were similar in the two groups except for the severity of the CAD. At 30 days, the death rate (PCI: 2.1% vs. CABG: 9.6%, p=0.21) and major adverse cardiac events (MACE) rate (PCI: 2.1% vs. CABG: 9.6%, p=0.21) were similar in comparisons between the PCI and CABG groups. At three years, the death rate (PCI: 18.8% vs. CABG: 19.2%, p=0.94) was similar between the PCI and CABG groups but the MACE rate (PCI: 47.9% vs. CABG: 21.2%, p=0.006) was higher in the PCI group compared to the CABG group. In addition, the repeat revascularization rate was higher in the PCI group compared to the CABG group (PCI: 12.5% vs. CABG: 1.9%, p=0.046).

CONCLUSIONS

The CABG procedure was associated with a lower incidence of MACE and repeat revascularization for up to three years of follow-up in DN patients with CAD. However, the overall survival rate was similar in the CABG and PCI groups. Therefore, CABG may be superior to PCI with regard to MACE and repeat revascularization.

All-cause and cardiovascular mortality in diabetic subjects increases significantly with reduced estimated glomerular filtration rate (eGFR): 10 years' data from the South Tees Diabetes Mortality study

AIMS

To investigate the association between estimated glomerular filtration rate (eGFR) and total and cardiovascular mortality in a population-based cohort of diabetic subjects.

METHODS

A longitudinal study using a population-based district diabetes register comprising 3288 subjects in South Tees, UK. The eGFR was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Patients were stratified by baseline eGFR into five stages as per the National Kidney Foundation guidelines: Stage 1, eGFR > 90; Stage 2, eGFR 60-89; Stage 3, eGFR 30-59; Stage 4, eGFR 15-29; and Stage 5, eGFR < 15 ml/min per 1.73 m(2). Main outcome was all-cause and cardiovascular mortality between 1 January 1994 and 31 July 2004.

RESULTS

At baseline, mean age (58.4 years) differed between groups. Persons with lower eGFR were older (P < 0.001). Thirty-six percent (n = 1193, males 56%) had died by 10 years (cardiovascular cause in 60%). Median follow-up was 10.5 years amounting to 28 342 person years. Stages 4 and 5 (eGFR <or= 29 ml/min per 1.73 m(2)) were amalgamated for mortality analysis. Total and cardiovascular mortality increased with reduced eGFR. Adjusted hazard ratios (HR) [95% confidence interval (CI)] for all-cause mortality comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.28 (1.02, 1.60), 2.58 (2.05, 3.25) and 6.42 (4.25, 9.71), respectively. Adjusted HRs (95% CI) for mortality due to circulatory disease comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.50 (1.10, 2.06), 3.32 (2.41, 4.58) and 7.99 (4.69, 13.62), respectively.

CONCLUSIONS

In diabetic subjects, mortality increases significantly with reduced GFR. Low eGFR identifies patients at high risk of cardiovascular mortality who should be targeted for aggressive risk factor modification.

Increased prevalence of coronary artery disease, silent myocardial ischemia, complex ventricular arrhythmias, atrial fibrillation, left ventricular hypertrophy, mitral annular calcium, and aortic valve calcium in patients with chronic renal insufficiency

Cardiovascular morbidity and mortality is high in patients with chronic renal insufficiency. Patients with chronic renal insufficiency have an increased prevalence of coronary artery disease, silent myocardial ischemia, complex ventricular arrhythmias, atrial fibrillation, left ventricular hypertrophy, mitral annular calcium, and aortic valve calcium than patients with normal renal function. These risk factors for cardiovascular morbidity and mortality contribute to the increased incidence of cardiovascular morbidity and mortality seen in patients with chronic renal insufficiency.

A five-year comparison of the renal protective effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in patients with non-diabetic nephropathy

OBJECTIVE

Evidence suggests that the effectiveness of angiotensin-converting enzyme (ACE) inhibition diminishes with time, resulting in increasing angiotensin II levels, the action of which can be inhibited by the addition of an angiotensin receptor blocker (ARB). In the present study, the renal protective effects of ACE inhibitors and ARBs were compared over a five-year period in a prospective, randomized, open-blind study in 68 nondiabetic Japanese patients with elevated serum creatinine levels.

PATIENTS AND METHODS

Japanese patients with renal insufficiency were randomly assigned to receive either an ACE inhibitor (benazepril 1.25 to 5 mg daily or trandolapril 0.5 to 4 mg daily) or ARB (candesartan 2 to 8 mg daily or losartan 25 to 100 mg daily) at the Kidney Disease Center at Saitama Medical School Hospital. The primary study endpoint was a change in glomerular filtration rate (GFR) between the baseline value and the last available value obtained during the five-year treatment period, as estimated by the Cockcraft-Gault equation. Secondary endpoints included the annual changes in GFR, serum creatinine level, urinary protein excretion, and blood pressure, as well as the rate of development of endstage renal disease.

RESULTS

There were no significant differences in the primary endpoint between the two groups. However, after 4 years, the decline in GFR in patients treated with ARBs was significantly greater than that seen in patients treated with an ACE inhibitor (p<0.05). Furthermore, the rate of introduction of dialysis therapy was also significantly greater in the ARB-treated patients (52.7% in ACE inhibitor and 81.2% in ARB group at year 5. p<0.01).

CONCLUSION

While our data suggested that ARB, like ACE, treatment might slow the progression of renal dysfunction, it also pointed to the necessity to be alerted to the progression to endstage renal disease with longterm medication.