Göknur Tekin

Efficacy of allopurinol pretreatment for prevention of contrast-induced nephropathy: a randomized controlled trial

BACKGROUND Contrast-induced nephropathy (CIN) remains a common complication of radiographic procedures. Radiocontrast agents can cause a reduction in renal function that may be due to reactive oxygen species. Conflicting evidence suggests that administration of antioxidants prevents CIN. METHODS We assessed the efficacy of allopurinol in preventing CIN. We prospectively randomized 159 patients with a serum creatinine concentration >1.1mg/dL undergoing cardiac catheterization/interventions to receive allopurinol (300 mg, p.o.) 24h before administration of radiocontrast agent and hydration (1mg/kg/hN/saline for 12h pre- and post-contrast, n=79), or hydration alone (1mg/kg/hN/saline for 12h pre- and post-contrast, n=80). RESULTS CIN occurred in 6 of 80 patients (7.5%) in the control group and no subjects in the allopurinol group (p=0.013). In the allopurinol group, median serum creatinine concentration decreased significantly from 1.43 mg/dL [1.1-4.15 mg/dL] to 1.35 mg/dL [0.7-4.15 mg/dl] at 48 h and to 1.27 mg/dL [0.66-4.37 mg/dL] at 4 days after radiocontrast administration (p<0.0001 and p<0.0001 compared with baseline, respectively). In the control group, median serum creatinine concentration decreased non-significantly from 1.48 mg/dL [1.1-2.96 mg/dL] to 1.43 mg/dL [0.73-3.02 mg/dL] and to 1.45 mg/dL [0.86-3.71 mg/dL] (p=0.045 and p=0.57, respectively) 48 h and 4 days after radiocontrast administration. CONCLUSIONS Prophylactic oral administration of allopurinol, along with hydration, may protect against CIN in high-risk patients undergoing coronary procedures.

Short- and long-term effect of simvastatin therapy on the heterogeneity of cardiac repolarization in diabetic patients

The interlead variability of QT interval in the 12-lead electrocardiogram, QT dispersion (QTd), has been shown to reflect dispersion of ventricular refractoriness and may provide a measure of arrhythmogenic potential in diabetic patients. QTd and heart rate corrected QTd (QTcd) were also proposed to be accurate predictors of cardiac death in patients with diabetes. In recent years, experimental and clinical evidence demonstrates that statins exert antiarrhythmic properties. Therefore, in the present study, we have examined whether simvastatin treatment has any effect on the QTd and QTcd in patients with diabetes mellitus. Sixty type 2 diabetic patients without known coronary artery disease and low-density lipoprotein cholesterol >100mg/dl and 30 age and sex-matched non-diabetic controls were included in a prospective study. Out of 60 diabetic patients, 30 were treated with simvastatin 40 mg/day for 1 year and the remaining 30 subjects were served as diabetic controls. No lipid lowering therapy was administered to the diabetic and the non-diabetic controls. QTd and QTcd of treated diabetics and the non-diabetic controls were measured at baseline, 6, 12 weeks and at 1 year. QTd and QTcd of the diabetic controls were obtained at baseline, 6 and 12 weeks. Both QTd and QTcd were significantly greater in patients with the diabetes than in the non-diabetic controls at baseline (52+/-13 ms vs. 41+/-12 ms, p<0.001 and 62+/-17 ms vs. 42+/-11 ms, p<0.001, respectively). Simvastatin therapy significantly decreased both QTd and QTcd at the end of first year compared to baseline (51+/-15 ms vs. 33+/-11 ms, p<0.001 and 60+/-18 ms vs. 38+/-12 ms, p<0.001, respectively). No significant change were found in QTd and QTcd in the non-diabetic (p=0.29 and p=0.87 by ANOVA, respectively) and in the diabetic controls (p=0.72 and p=0.57, by ANOVA, respectively). This study suggests for the first time that simvastatin treatment in diabetic patients with hyperlipidemia is associated with an improvement in the heterogeneity of cardiac repolarization. This may be one of the mechanisms for the reduction in clinical events reported in the survival studies with statins. Further prospective randomized studies are warranted to confirm our findings.

Short-term effects of fluvastatin therapy on plasma interleukin-10 levels in patients with chronic heart failure.

BackgroundExperimental data demonstrated that inflammatory mediators, such as pro-inflammatory and anti-inflammatory cytokines and their receptors might have important role in the development and the progression of heart failure (HF). Statins were shown to downregulate inflammatory cytokines in HF. Interleukin (IL)-10 is one of the most important anti-inflammatory cytokines. The effect of statin therapy on plasma IL-10 levels is not known in patients with HF. We conducted this study to investigate the effects of fluvastatin therapy on plasma IL-10 cytokine concentration in patients with HF. MethodsA total of 29 patients with ischemic HF were included in this prospective uncontrolled study. Patients were assigned to fluvastatin (80 mg/day) after baseline examinations. Determination of biochemical parameters including lipids, IL-10, and tumor necrosis factor-&agr; were performed at baseline and 12 weeks after the initiation of fluvastatin therapy. All participants also underwent symptom-limited exercise tolerance test at baseline and 12 weeks, and heart rate recovery (HRR) was calculated. ResultsA significant elevation in the plasma levels of IL-10 after 12 weeks of fluvastatin treatment (4.8±1.0 vs. 6.5±1.3 pg/ml, P=0.002) was observed. Plasma tumor necrosis factor-&agr; levels were significantly decreased after fluvastatin therapy (6.3±2.3 vs. 4.8±1.4 pg/ml, P=0.003). Fluvastatin therapy significantly improved HRR at 1 min after 12 weeks compared with baseline (19±7 vs. 24±9 bpm, P<0.001). A positive correlation between the change in the levels of IL-10 and the change in HRR at 1 min (r=0.57, P<0.001) was observed. ConclusionFluvastatin therapy might lead to an increase in plasma IL-10 levels and an associated improvement in vagal tonus as assessed by HRR at 1 min in patients with HF. These findings might partly explain the possible benefit observed in statin trials.

Heart Rate Recovery and Physical Conditioning

tivity Questionnaire (IPAQ). The study population could be matched with respect to physical activity using the IPAQ. The IPAQ version that we use in our studies is the short last 7-day recall questionnaire. This version consists of seven questions assessing the frequency and duration of participation in vigorous, moderate intensity and walking activity as well as the time spent sitting during a weekday, globally in all contexts of everyday life. Scores for vigorous, moderate and walking activity are calculated in minutes per week, as is the time spent sitting. The sum of the three activity scores gives an indicator of total physical activity. After multiplying the number of hours per week of each type of activity by an average metabolic cost (metabolic equivalents of task, MET), an energy expenditure indicator can also be obtained expressed in MET-minutes per week. Detailed information about the IPAQ and the methods of scoring is available at www.ipaq.ki.se. We suggest that the studies involving HRR consist of a population matched with respect to physical activity. Dear Editor, We read with great interest the article by Sarli et al. [1] investigating the relationship between psoriasis and the heart rate recovery (HRR) index. They found that HRR 1–5 was significantly lower in patients with psoriasis compared to healthy controls and that HRR 1 was well correlated with the duration of psoriasis (r = 0.541, p < 0.001), the psoriasis area and the severity index score (r = 0.511, p < 0.001). Although we agree with their findings and conclusions, we have some concerns in interpreting the results of the findings and the design of the studies involving HRR. The HRR at 1 min of exercise is a marker of parasympathetic activity [2] . Parasympathetic activity and HRR are influenced not only by various disease processes such as obesity, insulin resistance, diabetes, hypertension, hypercholesterolemia, depression, anxiety, heart failure, and peripheral vascular disease [3] but also by various drugs [4] and physical fitness [5] . People who are in excellent physical shape have high levels of parasympathetic tone. Among patients with suspected coronary artery disease, there is a strong dose-response relationship between HRR and physical fitness [6] . Thus, attenuated HRR in a particular disease might be due to poor physical fitness rather than the disease itself. A standardized measurement of physical activity of a study population could be assessed using the International Physical AcPublished online: December 20, 2014

Heart rate recovery and methodological issues.

1. Günaydın ZY, Gürel YE, Erdoğan G, Kaya A. Peripartum cardiomyopathy associated with triplet pregnancy. Anadolu Kardiyol Derg 2014; 14: 661-2. [CrossRef] 2. Rajab KE, Issa A. Peripartum Cardiomypathy. A five year hospital-based analytical study Bahrain Med Bull 2004; 26: 3. 3. Biteker M, Ilhan E, Biteker G, Duman D, Bozkurt B. Delayed recovery in peripartum cardiomyopathy: an indication for long-term follow-up and sustained therapy. Eur J Heart Fail 2012; 14: 895-901. [CrossRef] 4. Michael M. Givertz. Peripartum Cardiomyopathy Circulation 2013; 127: 622-6. [CrossRef] 5. Garg J, Palaniswamy C, Lanier G. Peripartum Cardiomyopathy: Definition, Incidence, Etiopathogenesis, Diagnosis and Management. Cardiol Rev 2014 Aug 8. Epub ahead of print. [CrossRef]