Use of Renin-Angiotensin Inhibitors in People with Renal Artery Stenosis

Background and objectives

People with atherosclerotic renal artery stenosis may benefit from renin-angiotensin inhibitors, angiotensin-converting enzyme inhibitors, and angiotensin-receptor blockers, but little is known about the factors associated with their use.

Design, setting, participants, & measurements

The Cardiovascular Outcomes in Renal Atherosclerotic Lesions study (ClinicalTrials.gov identified: {"type":"clinical-trial","attrs":{"text":"NCT00081731","term_id":"NCT00081731"}}NCT00081731) is a prospective, international, multicenter clinical trial that randomly assigned participants with atherosclerotic renal artery stenosis who received optimal medical therapy to stenting versus no stenting from May 2005 through January 2010. At baseline, medication information was available from 853 of 931 randomly assigned participants. Kidney function was measured by serum creatinine–based eGFR at a core laboratory.

Results

Before randomization, renin-angiotensin inhibitors were used in 419 (49%) of the 853 participants. Renin-angiotensin inhibitor use was lower in those with CKD (eGFR<60 ml/min per 1.73 m²) (58% versus 68%; P=0.004) and higher in individuals with diabetes (41% versus 27%; P<0.001). Presence of bilateral renal artery stenosis or congestive heart failure was not associated with renin-angiotensin inhibitor use. Although therapy with renin-angiotensin inhibitors varied by study site, differences in rates of use were not related to the characteristics of the site participants. Participants receiving a renin-angiotensin inhibitor had lower systolic BP (mean±SD, 148±23 versus 152±23 mmHg; P=0.003) and more often had BP at goal (30% versus 22%; P=0.01).

Conclusions

Kidney function and diabetes were associated with renin-angiotensin inhibitor use. However, these or other clinical characteristics did not explain variability among study sites. Patients with renal artery stenosis who received renin-angiotensin inhibitor treatment had lower BP and were more likely to be at treatment goal.     

Outcome of blood pressure and renal function in patients with renal artery stenosis after stenting

OBJECTIVE

To study the response of systolic and diastolic blood pressure (BP) and renal function after renal artery stenting at three months, six months, one year and last follow-up.

METHODS

Patients with significant renal artery stenosis who underwent angioplasty with stenting from January 1999 to September 2006 were analyzed. The BP and serum creatinine levels were recorded at baseline, three months, six months, one year and at last follow-up. Generalized estimating equations were applied to analyze the changes in blood pressure and serum creatinine over time.

RESULTS

There were 32 patients – 21 Chinese, six Malay and five Indian. The male to female ratio was 1.3:1. The mean age (± SD) was 69.4±8.8 years. The mean follow-up time was 1.8±1.6 years (range 0.5 to six years). When compared with the baseline BP, there was significant improvement at three months, six months, one year and at last follow-up. In the diabetes mellitus (DM) group, there was deterioration in serum creatinine. In the non-DM group, there was stabilization of serum creatinine with improvement at one year.

CONCLUSION

Significant improvement in BP occurs in renal artery stenosis patients after stenting. In patients without DM, renal function remains stable or improves. However, in DM patients, especially those with proteinuria, there is deterioration in renal function.     

Periprocedural plasma fibrinogen levels and coronary stent outcome

Aim

Percutaneous intervention is one of the treatment option for coronary artery disease. Reinfarction and restenosis is one of the complication of the procedure. So this study was conducted to assess plasma fibrinogen levels pre- and post coronary stenting and its relation with outcome.

Methods

After obtaining informed consent, venous blood samples were collected at three timed points in relation to stenting – 24 h before, 24 h after and 72 h after stenting to assess fibrinogen levels. Patients were followed up for six months. Repeat revascularization, myocardial infarction and symptomatic angina were considered as major adverse clinical events.

Results

57 patients who underwent successful stenting and followed up for six months up were included in the study. Mean age was 53 years and 87.7% were males and 29.8% were diabetics. Baseline plasma fibrinogen level was significantly high in patients who developed repeat angina and myocardial infarction after the stenting [288.64 ± 59.43 vs 393.75 ± 32.97 mg/dL, p = 0.003] and it remained high during serial assessment [322.74 ± 63.92 vs 422.00 ± 55.28 mg/dL, 326.23 ± 65.81 vs 419.50 ± 45.82 mg/dL, 0.008, 0.012 respectively]. Patients who developed adverse events denied any drug default.

Conclusion

We conclude that plasma fibrinogen plays a significant role in the development of adverse events following stenting shown by high level of plasma fibrinogen in patients who developed adverse events.     

Linking soluble vascular adhesion molecule-1 level to calcific aortic stenosis in patients with coronary artery disease

BACKGROUND:

Calcific aortic stenosis (AS) is an atherosclerosis-related process and the most common cause of valve disease requiring surgery.

OBJECTIVE:

To assess the association of inflammatory markers with AS in advanced atherosclerosis.

METHODS:

Consecutive patients with coronary artery disease (CAD) associated with AS were prospectively identified (mean transvalvular aortic gradient of 30 mmHg or greater). Subjects with aortic sclerosis (mean transvalvular aortic gradient of 10 mmHg or less) served as controls. All patients underwent clinical evaluation, echocardiography and coronary angiography.

RESULTS:

One hundred twenty-two patients with AS (85 men) and 101 with aortic sclerosis (76 men) of similar CAD severity were enrolled. The AS patients were older (mean [± SD] 71±7 years versus 66±7 years; P<0.001), had higher soluble vascular adhesion molecule-1 (s-VCAM-1) levels (1533±650 μg/L versus 1157±507 μg/L; P<0.001), but lower soluble intercellular adhesion molecule-1 (s-ICAM-1) (254±81 μg/L versus 293±84 μg/L; P<0.01) and soluble E-selectin (53±28 μg/L versus 62±29 μg/L; P<0.05) levels. The two groups did not differ with respect to C-reactive protein level (3±2.9 mg/L versus 3.4±2.6 mg/L; P not significant). Higher s-VCAM-1 (OR 1.09, 95% CI 1.04 to 1.14; P<0.001) and lower s-ICAM-1 (OR 0.82, 95% CI 0.72 to 0.94; P<0.001) levels were associated with AS after adjustment for age.

CONCLUSION:

Increased s-VCAM-1 levels were associated with calcific AS in patients with significant CAD.     

Experience of stenting for atherosclerotic renal artery stenosis in a cardiac catheterization laboratory: Technical considerations and complications

BACKGROUND

Atherosclerotic renal artery (RA) stenosis contributes to hypertension, renal insufficiency and end stage renal disease, and is independently associated with adverse cardiovascular events. Percutaneous renal intervention is efficacious in treating renovascular hypertension and may be effective in stabilizing or improving renal function, thereby reducing cardiovascular risk. However, high rates of procedural complications have been reported.

OBJECTIVES

To determine the nature and frequency of complications of percutaneous renal intervention using contemporary techniques and equipment in a high-volume cardiac catheterization laboratory.

METHODS

Consecutive patients undergoing attempted RA stenting for atherosclerotic RA stenosis in the cardiac catheterization laboratory at the Vancouver General Hospital (Vancouver, British Columbia) between June 2000 and March 2007 were enrolled in a prospective registry. Baseline clinical characteristics, procedural and technical information, and complications were recorded.

RESULTS

A total of 132 RAs were stented in 106 patients during 108 procedures. The procedural success rate was 100%, with no related death, myocardial infarction, nephrectomy or dialysis. Major complications included three pseudoaneurysms (2.8%) and acute deterioration in renal function in six patients (5.5%), although renal function returned to baseline in one patient at 12 months.

CONCLUSIONS

RA stenting can be successfully and safely performed using contemporary techniques, and the low complication rates described should be the minimum standard for contemporary trials evaluating RA stenting.     

Refractory hypertension with massive proteinuria may be reversed in renal artery stenosis patients with low proteinuria selectivity index after stenting

Background

No available prognostic factor was identified for atherosclerotic renovascular stenosis (ARAS) patient who undergo the percutaneous revascularization therapy.

Report

This is a case of 68-year-old ARAS patient associated with hypertension and massive proteinuria, who exhibited progressive aggravation of renal dysfunction. His proteinuria selectivity index (SI) was only 0.08. Then the stenosis was treated by percutaneous transluminal angioplasty of the renal artery (PTRA) and stenting. After 2-year follow up, all symptoms including renal dysfunction and uncontrolled hypertension was well-controlled.

Discussion

As no reliable predictors of clinical response have been identified yet, SI might be a simple prognositic index for ARAS patients undergone the revascularzation therapy.KEY WORDS : Atherosclerotic renovascular stenosis (ARAS), Refractory hypertension, proteinuria, selectivity index (SI), revascularzation therapy, renal artery stenosis     

Successful percutaneous management of Lutembacher syndrome

Background

The surgical management of Lutembacher syndrome is straight forward but percutaneous management, though technically demanding, is always desirable.

Methods

A 17 year old unmarried female presented with severe Mitral stenosis and a 19 mm almost circular Ostium secundum ASD with moderate pulmonary artery hypertension and dilated right sided chambers. She was managed in a staged manner. Percutaneous trans mitral commissurotomy (PTMC) was done first, using a 26 mm Inoue balloon catheter set, and after 48 h, ASD was closed with a 20 mm Cocoon Septal Occluder.

Results

The mitral valve area increased after PTMC from 0.8 cm² to 2.1 cm² and Q_P/Q_S decreased from 4.9 to 2. ASD was successfully closed under echocardiographic and fluoroscopic guidance.

Conclusion

Percutaneous management of the Lutembacher syndrome (PTMC and ASD device closure) is an effective and low risk procedure and avoids considerable morbidity and mental trauma for the patients.     

Associations of Triiodothyronine Levels with Carotid Atherosclerosis and Arterial Stiffness in Hemodialysis Patients

Summary

Background and objectives

End-stage renal disease is linked to alterations in thyroid hormone levels and/or metabolism, resulting in a high prevalence of subclinical hypothyroidism and low triiodothyronine (T3) levels. These alterations are involved in endothelial damage, cardiac abnormalities, and inflammation, but the exact mechanisms are unclear. In this study, we investigated the relationship between serum free-T3 (fT3) and carotid artery atherosclerosis, arterial stiffness, and vascular calcification in prevalent patients on conventional hemodialysis.

Design, setting, participants, & measurements

137 patients were included. Thyroid-hormone levels were determined by chemiluminescent immunoassay, carotid artery–intima media thickness (CA-IMT) by Doppler ultrasonography, carotid-femoral pulse wave velocity (c-f PWV), and augmentation index by Sphygmocor device, and coronary artery calcification (CAC) scores by multi-slice computerized tomography.

Results

Mean fT3 level was 3.70 ± 1.23 pmol/L. Across decreasing fT3 tertiles, c-f PWV and CA-IMT values were incrementally higher, whereas CACs were not different. In adjusted ordinal logistic regression analysis, fT3 level (odds ratio, 0.81; 95% confidence interval, 0.68 to 0.97), age, and interdialytic weight gain were significantly associated with CA-IMT. fT3 level was associated with c-f PWV in nondiabetics but not in diabetics. In nondiabetics (n = 113), c-f PWV was positively associated with age and systolic BP but negatively with fT3 levels (odds ratio = 0.57, 95% confidence interval 0.39 to 0.83).

Conclusions

fT3 levels are inversely associated with carotid atherosclerosis but not with CAC in hemodialysis patients. Also, fT3 levels are inversely associated with surrogates of arterial stiffness in nondiabetics.     

Renal sympathetic denervation using an externally irrigated radiofrequency ablation catheter for treatment of resistant hypertension – Acute safety and short term efficacy

Objectives

This study was conducted to assess the acute safety and short term efficacy of renal sympathetic denervation (RSDN) using solid tip radiofrequency ablation (RFA) catheter and saline irrigation through the renal guiding catheter to achieve effective denervation.

Background

RSDN using a specialized solid-tip RFA catheter has recently been demonstrated to safely reduce systemic blood pressure in patients with refractory hypertension, the limitation being inadequate power delivery in renal arteries. So, we used solid-tip RFA catheter along with saline irrigation for RSDN.

Methods

Nine patients with resistant hypertension underwent CT and conventional renal angiography, followed by bilateral or unilateral RSDN using 5F RFA catheter with saline irrigation through renal guiding catheter. Repeat renal angiography was performed at the end of the procedure. In all patients, pre- and post-procedure serum creatinine was measured.

Results

Over 1-month period: 1) the systolic/diastolic blood pressure decreased by −57 ± 20/−25 ± 7.5 mm Hg; 2) all patients experienced a decrease in systolic blood pressure of at least −36 mm Hg (range 36–98 mm Hg); 3) there was no evidence of renal artery injury immediate post-procedure. There was no significant change in serum creatinine level.

Conclusions

This data shows the acute procedural safety and short term efficacy of RSDN using modified externally irrigated solid tip RFA catheter.     

The platelet-to-lymphocyte ratio as a predictor of all-cause mortality in patients with coronary artery disease undergoing elective percutaneous coronary intervention and stent implantation

Background

There is no data regarding the association between the platelet-to-lymphocyte ratio (PLR) and long-term mortality in patients with stable coronary artery disease (SCAD). The aim of this study is to evaluate the utility of the pre-procedural PLR for predicting long-term, all-cause mortality in patients with SCAD undergoing percutaneous coronary intervention (PCI) and stent implantation.

Methods

We analyzed a total of 2959 consecutive patients with SCAD who underwent PCI (balloon angioplasty followed by stent implantation or direct stenting) between July 2006 and December 2011 at our institution. The patients were stratified into tertiles according to their admission PLR. The association between the PLR value and the outcomes was assessed using Cox proportional regression analysis after adjusting for clinical angiographic and laboratory data.

Results

During median follow-up of 1124 days, mortality was highest in patients with PLR within the 3rd tertile as compared to the 2nd and the 1st tertile (11.0% vs 8.7% vs. 9.6%, respectively, p = 0.03). PLR remained associated with mortality in multivariable analysis including clinical variables, ejection fraction and angiographic parameters HR (per 10 units increase) = 1.02 [95%CI,1.01 ÷ 1.04, p = 0.006]. After adjustment for the eGFR and hemoglobin levels, PLR was however no longer significantly associated with mortality.

Conclusion

PLR has potential predictive value in patients with SCAD, which has not been reported previously, but statistical significance disappears after adjusting for estimated glomerular filtration rate (eGFR) and hemoglobin levels as a potential confounding variable.     

Associations of Soluble CD14 and Endotoxin with Mortality,Cardiovascular Disease,and Progression of Kidney Disease among Patients with CKD

Background and objectives

CD14 plays a key role in the innate immunity as pattern-recognition receptor of endotoxin. Higher levels of soluble CD14 (sCD14) are associated with overall mortality in hemodialysis patients. The influence of kidney function on plasma sCD14 levels and its relationship with adverse outcomes in patients with CKD not yet on dialysis is unknown. This study examines the associations between plasma levels of sCD14 and endotoxin with adverse outcomes in patients with CKD.

Design, setting, participants, & measurements

We measured plasma levels of sCD14 and endotoxin in 495 Leuven Mild-to-Moderate CKD Study participants. Mild-to-moderate CKD was defined as presence of kidney damage or eGFR<60 ml/min per 1.73 m² for ≥3 months, with exclusion of patients on RRT. Study participants were enrolled between November 2005 and September 2006.

Results

Plasma sCD14 was negatively associated with eGFR (ρ=–0.34, P<0.001). During a median follow-up of 54 (interquartile range, 23–58) months, 53 patients died. Plasma sCD14 was predictive of mortality, even after adjustment for renal function, Framingham risk factors, markers of mineral bone metabolism, and nutritional and inflammatory parameters (hazard ratio [HR] per SD higher of 1.90; 95% confidence interval [95% CI],1.32 to 2.74; P<0.001). After adjustment for the same risk factors, plasma sCD14 was also a predictor of cardiovascular disease (HR, 1.30; 95% CI, 1.00 to 1.69; P=0.05). Although plasma sCD14 was associated with progression of CKD, defined as reaching ESRD or doubling of serum creatinine in models adjusted for CKD-specific risk factors (HR, 1.24; 95% CI, 1.01 to 1.52; P=0.04), significance was lost when adjusted for proteinuria (HR, 1.19; 95% CI, 0.96 to 1.48; P=0.11). There was neither correlation between plasma endotoxin and sCD14 (ρ=–0.06, P=0.20) nor was endotoxin independently associated with adverse outcome during follow-up.

Conclusions

Plasma sCD14 is elevated in patients with decreased kidney function and associated with mortality and cardiovascular disease in patients with CKD not yet on dialysis.     

Diagnostic importance of admission platelet volume indices in patients with acute chest pain suggesting acute coronary syndrome

Objective

Acute coronary syndrome (ACS) is a challenging issue in cardiovascular medicine. Given platelet role in atherothrombosis, we sought to determine whether platelet indices can be used as diagnostic tests for patients who suffered from an acute chest discomfort.

Methods

We prospectively enrolled 862 patients with an acute chest pain and 184 healthy matched controls. They were divided into four groups: 184 controls, 249 of non-ACS, 421 of unstable angina (UA), and 192 of myocardial infarction (MI) cases. Blood samples were collected at admission to the emergency department for routine hematologic tests.

Results

The mean platelet volume (MPV), platelet distribution width (PDW), and platelet large cell ratio (P-LCR) were significantly greater in patients with MI compared with those of non-ACS or control subjects. Negative and significant correlations existed between MPV, PDW, and P-LCR values and platelet count (P < 0.001). Receiver operating characteristic (ROC) curves showed that the MPV, PDW, and P-LCR with cut-off values of 9.15 fL, 11.35 fL, and 20.25% and with area under the curves of 0.563, 0.557, and 0.560, respectively, detected MI patients among those who had chest discomfort. The sensitivities and specificities were found to be 72% and 40%, 73% and 37%, and 68% and 44% for MPV, PDW, and P-LCR, respectively.

Conclusion

An elevated admission MPV, PDW, and P-LCR may be of benefit to detect chest pain resulting in MI from that of non-cardiac one, and also for risk stratification of patients who suffered from an acute chest discomfort.     

Circulating sCD36 is associated with unhealthy fat distribution and elevated circulating triglycerides in morbidly obese individuals

Background:

The recently identified circulating sCD36 has been proposed to reflect tissue CD36 expression, and is upregulated in case of obesity, insulin resistance and hepatic steatosis. The aim of this study was to explore the effect of weight loss secondary to bariatric surgery in relation to sCD36 among morbidly obese individuals. Furthermore, we investigated the levels of sCD36 in relation to obesity-related metabolic complications, low-grade inflammation and fat distribution.

Methods:

Twenty morbidly obese individuals (body mass index (BMI) 43.0±5.4 kg m⁻²) with a referral to Roux-en-Y gastric bypass were included. Anthropometric measurements and fasting blood samples were collected at a preoperative baseline visit and 3 months after surgery. sCD36 was measured by an in-house assay, whereas insulin sensitivity and the hepatic fat accumulation were estimated by the homeostasis model assessment (HOMA-%S) and liver fat percentage (LF%), respectively.

Results:

Postoperatively, BMI was reduced by 20% to 34.3±5.2 kg m⁻² (P<0.001). sCD36 was reduced by 31% (P=0.001) and improvements were observed in the amount of fat mass (P<0.001), truncal fat mass (P<0.001), circulating triglycerides (P=0.001), HOMA-%S (P=0.007), LF% (P=0.001) and the inflammatory marker high-sensitive C-reactive protein (P=0.005). sCD36 correlated with triglycerides (ρ=0.523, P=0.001) and truncal fat mass (ρ=0.357, P=0.026), and triglycerides were found to be an independent predictor of sCD36. At baseline, participants with the metabolic syndrome had a higher LF% and higher levels of the inflammatory biomarker YKL-40 (P=0.003 and P=0.014) as well as a tendency towards higher levels of sCD36.

Conclusion:

sCD36 was reduced by weight loss and associated with an unhealthy fat accumulation and circulating triglycerides, which support the proposed role of sCD36 as a biochemical marker of obesity-related metabolic complications and risks.     

Differences in GFR and Tissue Oxygenation,and Interactions between Stenotic and Contralateral Kidneys in Unilateral Atherosclerotic Renovascular Disease

Background and objectives

Atherosclerotic renal artery stenosis (ARAS) can reduce renal blood flow, tissue oxygenation, and GFR. In this study, we sought to examine associations between renal hemodynamics and tissue oxygenation with single-kidney function, pressor hormones, and inflammatory biomarkers in patients with unilateral ARAS undergoing medical therapy alone or stent revascularization.

Design, setting, participants, & measurements

Nonrandomized inpatient studies were performed in patients with unilateral ARAS (>60% occlusion) before and 3 months after revascularization (n=10) or medical therapy (n=20) or patients with essential hypertension (n=32) under identical conditions. The primary study outcome was change in single-kidney GFR. Individual kidney hemodynamics and volume were measured using multidetector computed tomography. Tissue oxygenation (using R²* as a measure of deoxyhemoglobin) was determined by blood oxygen level–dependent magnetic resonance imaging at 3 T. Renal vein neutrophil gelatinase–associated lipocalin (NGAL), monocyte chemoattractant protein-1 (MCP-1), and plasma renin activity were measured.

Results

Total GFR did not change over 3 months in either group, but the stenotic kidney (STK) GFR rose over time in the stent compared with the medical group (+2.2[−1.8 to 10.5] versus −5.3[−7.3 to −0.3] ml/min; P=0.03). Contralateral kidney (CLK) GFR declined in the stent group (43.6±19.7 to 36.6±19.5 ml/min; P=0.03). Fractional tissue hypoxia fell in the STK (fraction R²* >30/s: 22.1%±20% versus 14.9%±18.3%; P<0.01) after stenting. Renal vein biomarkers correlated with the degree of hypoxia in the STK: NGAL(r=0.3; P=0.01) and MCP-1(r=0.3; P=0.02; more so after stenting). Renal vein NGAL was inversely related to renal blood flow in the STK (r=−0.65; P<0.001). Biomarkers were highly correlated between STK and CLK, NGAL (r=0.94; P<0.001), and MCP-1 (r=0.96; P<0.001).

Conclusions

These results showed changes over time in single-kidney GFR that were not evident in parameters of total GFR. Furthermore, they delineate the relationship of measurable tissue hypoxia within the STK and markers of inflammation in human ARAS. Renal vein NGAL and MCP-1 indicated persistent interactions between the ischemic kidney and both CLK and systemic levels of inflammatory cytokines.     

Human Tissue Kallikrein Activity in Angiographically Documented Chronic Stable Coronary Artery Disease

Background

Human tissue kallikrein (hK1) is a key enzyme in the kallikrein–kinin system (KKS). hK1-specific amidase activity is reduced in urine samples from hypertensive and heart failure (HF) patients. The pathophysiologic role of hK1 in coronary artery disease (CAD) remains unclear.

Objective

To evaluate hK1-specific amidase activity in the urine of CAD patients

Methods

Sixty-five individuals (18–75 years) who underwent cardiac catheterism (CATH) were included. Random midstream urine samples were collected immediately before CATH. Patients were classified in two groups according to the presence of coronary lesions: CAD (43 patients) and non-CAD (22 patients). hK1 amidase activity was estimated using the chromogenic substrate D-Val-Leu-Arg-Nan. Creatinine was determined using Jaffé’s method. Urinary hK1-specific amidase activity was expressed as µM/(min · mg creatinine) to correct for differences in urine flow rates.

Results

Urinary hK1-specific amidase activity levels were similar between CAD [0.146 µM/(min ·mg creatinine)] and non-CAD [0.189 µM/(min . mg creatinine)] patients (p = 0.803) and remained similar to values previously reported for hypertensive patients [0.210 µM/(min . mg creatinine)] and HF patients [0.104 µM/(min . mg creatinine)]. CAD severity and hypertension were not observed to significantly affect urinary hK1-specific amidase activity.

Conclusion

CAD patients had low levels of urinary hK1-specific amidase activity, suggesting that renal KKS activity may be reduced in patients with this disease.     

Evaluation of platelet function during extended storage in additive solution, prepared in a new container that allows manual buffy-coat platelet pooling and leucoreduction in the same system

Background

A novel and practical storage container designed for manual buffy-coat pooling and leucodepletion was evaluated to assess its filtration performance and to analyse the quality of stored leucoreduced buffy-coat-derived platelet pools.

Materials and methods.

To analyse the Grifols Leucored^® Transfer PL system, blood was collected from random donors into standard triple bag systems, and fractionated using standard procedures to obtain buffy-coats. Ten leucodepleted platelet pools were prepared each from five units of buffy-coats in additive solution. Concentrates were stored for 10 days at 22 °C on an end-over-end agitator. On days 0, 5, 7, and 10 of storage, samples were tested using standard in vitro platelet parameters.

Results

The use of this novel system for volume reduction and leucodepletion of buffy-coats resuspended in additive solution led to platelet pools that met the European requirements. pH was maintained well, declining from an initial value of 7.11±0.04 to 6.88±0.08 after 10 days. Parameters of cell lysis, response to a hypotonic stimulus and aggregation induced by agonists (arachidonic acid, ristocetin, collagen or thrombin receptor activating peptide) were also well-preserved. During storage, the quality profile of the platelet pools remained very similar to that previously reported in platelet concentrates in terms of metabolism, platelet activation (CD62, CD63, sCD62), expression of glycoproteins Ib and IIb/IIIa, capacity of glycoprotein IIb/IIIa to become activated upon ADP stimulation, and release of biological response modifiers (sCD40L and RANTES).

Discussion.

This new system allows the preparation of leucodepleted buffy-coat platelet pools in additive solution with good preservation of platelet function. The logistics of the procedure are relatively simple and it results in good-quality components, which may reduce costs and ease the process of buffy-coat pooling and leucocyte reduction in transfusion services.     

Analysis of the Sensitivity and Specificity of Noninvasive Imaging Tests for the Diagnosis of Renal Artery Stenosis

Background

Aging and atherosclerosis are related to renovascular hypertension in elderly individuals. Regardless of comorbidities, renal artery stenosis is itself an important cause of cardiovascular morbidity and mortality.

Objective

To define the sensitivity, specificity, positive predictive value, and negative predictive value of noninvasive imaging tests used in the diagnosis of renal artery stenosis.

Methods

In a group of 61 patients recruited, 122 arteries were analized, thus permitting the definition of sensitivity, specificity, and the relative contribution of each imaging study performed (Doppler, scintigraphy and computed tomographic angiography in comparison to renal arteriography).

Results

The mean age was 65.43 years (standard deviation: 8.7). Of the variables related to the study population that were compared to arteriography, two correlated with renal artery stenosis, renal dysfunction and triglycerides. The median glomerular filtration rate was 52.8 mL/min/m². Doppler showed sensitivity of 82.90%, specificity of 70%, a positive predictive value of 85% and negative predictive value of 66.70%. For tomography, sensitivity was 66.70%, specificity 80%, positive predictive value 87.50% and negative predictive value 55.20%. With these findings, we could identify the imaging tests that best detected stenosis.

Conclusion

Tomography and Doppler showed good quality and efficacy in the diagnosis of renal artery stenosis, with Doppler having the advantage of not requiring the use of contrast medium for the assessment of a disease that is common in diabetics and is associated with renal dysfunction and severe left ventricular dysfunction.     

The Microvasculature in Chronic Kidney Disease

Summary

Background and objectives

Individuals with chronic kidney disease (CKD) stages 3 to 5 have an increased risk of cardiac and other vascular disease. Here we examined the association of CKD 3 to 5 with small vessel caliber.

Design, setting, participants, & measurements

This was a cross-sectional observational study of 126 patients with CKD stages 3 to 5 (estimated GFR [eGFR] <60 ml/min per 1.73 m²) and 126 age- and gender-matched hospital patients with CKD 1 or 2. Retinal vessel diameters were measured from digital fundus images by a trained grader using a computer-assisted method and summarized as the central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE).

Results

Patients with CKD 3 to 5 had a smaller mean CRAE and CRVE than hospital controls (139.4 ± 17.8 μm versus 148.5 ± 16.0 μm, P < 0.001; and 205.0 ± 30.7 μm versus 217.4 ± 25.8 μm, respectively; P = 0.001). CRAE and CRVE decreased progressively with each stage of renal failure CKD1–2 to 5 (P for trend = 0.08 and 0.04, respectively). CKD and hypertension were independent determinants of arteriolar narrowing after adjusting for age, gender, diabetes, dyslipidemia, and smoking history. Patients with CKD 5 and diabetes had a larger mean CRAE and CRVE than nondiabetics (141.4 ± 14.9 μm versus 132.9 ± 14.2 μm; 211.1 ± 34.4 μm versus 194.8 ± 23.8 μm).

Conclusions

The microvasculature is narrowed in patients with reduced eGFR.     

Do circulating blood cell types correlate with modifiable risk factors and outcomes in patients with acute coronary syndrome (ACS)?

Aims

Atherosclerosis is an inflammatory process with different cardiovascular risk factors (CVRFs) contributing to its pathogenesis. We aimed to evaluate the specific relationship between circulating blood leukocytes, troponin I and CVRFs.

Methods

We prospectively enrolled 959 patients with evidence of acute coronary syndrome either in form of unstable angina or STEMI or NSTEMI. Details demographic characteristics, CVRF and biochemical parameters such as total white blood cells (WBC), neutrophil, lymphocytes, platelet, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and troponin I were collected.

Results

The results indicated that patients having either hypertension, diabetes or smoking habit had significantly higher levels of total WBC (p = 0.013), neutrophil (p = 0.029), NLR (p = 0.029) and PLR (p = 0.009). The level of troponin I was unaffected by these risk factors. Significant association of hypertension was found with total WBC (p = 0.0392), lymphocytes (p = 0.0384) and PLR (p = 0.0027), whereas in diabetes and females all other leukocyte subtypes were significantly altered except for platelet and troponin I. Smokers had higher level of total WBC count (p = 0.0033) and PLR (p = 0.0464). No relationship between CVRFs and leukocytes was observed in males. The age independent effect was observed with PLR, whereas association with total WBC, lymphocytes, NLR, platelet was specific in older population. In younger patients NLR (p = 0.0453) is more likely to be elevated. Mortality was significantly associated with changes in the leukocytes but not with the CVRF presence.

Conclusion

We demonstrate that the neutrophils, lymphocytes and total WBC along with its ratios predict mortality and are more likely to be elevated in presence of CVRFs.     

Cross-match-compatible platelets improve corrected count increments in patients who are refractory to randomly selected platelets

Background

Cross-match-compatible platelets are used for the management of thrombocytopenic patients who are refractory to transfusions of randomly selected platelets. Data supporting the effectiveness of platelets that are compatible according to cross-matching with a modified antigen capture enzyme-linked immunosorbent assay (MAC-ELISA or MACE) are limited. This study aimed to determine the effectiveness of cross-match-compatible platelets in an unselected group of refractory patients.

Materials and methods

One hundred ABO compatible single donor platelet transfusions given to 31 refractory patients were studied. Patients were defined to be refractory if their 24-hour corrected count increment (CCI) was <5×10⁹/L following two consecutive platelet transfusions. Platelets were cross-matched by MACE and the CCI was determined to monitor the effectiveness of platelet transfusions.

Results

The clinical sensitivity, specificity, positive predictive value and negative predictive value of the MACE-cross-matched platelets for post-transfusion CCI were 88%, 54.6%, 39.3% and 93.2%, respectively. The difference between adequate and inadequate post-transfusion 24-hour CCI for MACE cross-matched-compatible vs incompatible single donor platelet transfusions was statistically significant (p=0.000). The 24-hour CCI (mean±SD) was significantly higher for cross-match-compatible platelets (9,250±026.6) than for incompatible ones (6,757.94±2,656.5) (p<0.0001). Most of the incompatible cross-matches (73.2%) were due to anti-HLA antibodies, alone (55.3% of cases) or together with anti-platelet glycoprotein antibodies (17.9%).

Discussion

The clinical sensitivity and negative predictive value of platelet cross-matching by MACE were high in this study and such tests may, therefore, be used to select compatible platelets for refractory patients. A high negative predictive value demonstrates the greater chance of an adequate response with cross-matched-compatible platelets.