New insights into the mechanisms of diastolic dysfunction in patients with type 2 diabetes.

BACKGROUND: Little is known about the role of advanced glycation end products (AGEs) and their receptor (RAGE) in diabetic cardiovascular complications. Therefore, we aimed to evaluate the association of serum soluble RAGE (sRAGE) levels and left ventricular (LV) diastolic dysfunction in patients with type 2 diabetes. METHODS: Our study consisted of 40 patients with type 2 diabetes and 40 age- and sex-matched healthy control group. Subjects with age ≥ 50 years old and any cardiovascular risk factors or conditions were excluded from the study. Serum sRAGE levels determined by enzyme-linked immunosorbent assay and LV diastolic dysfunction were evaluated according to current American Society of Echocardiography guidelines. RESULTS: Baseline characteristics were similar between groups except body mass index, waist-hip ratio, and fasting glucose levels. Serum sRAGE level was significantly lower in diabetic group compared with control group (676 ± 128 vs. 1044 ± 344, p < 0.05). Diastolic dysfunction was observed in 50% of diabetic patients (40% grade I and 10% grade II). Correlation analysis showed that serum sRAGE was negatively correlated with duration of diabetes, septal E'/A', lateral E'/A', and average E/E'. In multivariate regression analysis, serum sRAGE level was strongly associated with diastolic dysfunction in patients with type 2 diabetes. CONCLUSION: Our study showed that serum sRAGE level was significantly lower in type 2 diabetic patients aged < 50 years old. Also, sRAGE has negative correlation with the duration of diabetes and it was significantly associated with the presence of diastolic dysfunction in type 2 diabetes.

Effect of age and plaque morphology on diagnostic accuracy of dual source multidetector computed tomography coronary angiography.

BACKGROUND: Multidetector computed tomography (MDCT) coronary angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. The purpose of this study is to investigate the effect of age and coronary plaque calcification on diagnostic accuracy of MDCT. METHODS: The patients were examined by using dual-source MDCT and conventional coronary angiography. MDCT results were analyzed with regard to the severity (> 50% stenosis) and morphology (non-calcified, mixed, or calcified) of coronary atherosclerotic plaques evaluated in a 16-segment model. RESULTS: In total, 181 patients (94 men and 87 women) with 2,687 coronary artery segments were examined with MDCT. Ninety three patients were older than 65 years of age (group A, 42 men) and 88 were younger (group B, 52 men). Two-hundred nine coronary artery segments (7.2%) were excluded because of small distal coronary vessel segments and/or motion artifacts. The overall number of segments with non-diagnostic image quality was similar in both groups of patients. Of the 2,687 evaluated segments, 157 (5.8%) were significantly diseased, and 144 of them were correctly detected by MDCT. Diagnostic evaluation showed that the sensitivity, positive predictive value, specificity, and negative predictive value were 89.5%, 62.5%, 96.0%, and 99.2%, respectively in group A, and 95.2%, 64.8%, 97.5%, and 99.8% in group B, respectively. In addition, detailed segment-based analyses in coronary segments with non-calcified, mixed and calcified plaques in both groups were similar diagnostic accuracy. CONCLUSIONS: Very high diagnostic accuracy observed in this study suggests that MDCT coronary angiography could be a suitable diagnostic tool for not only younger patients but also for older patients.

The relationship between circadian blood pressure pattern and ventricular repolarization dynamics assessed by QT dynamicity.

OBJECTIVE: The aim of the present cross-sectional study was to evaluate ventricular repolarization dynamics by QT dynamicity in normotensive and hypertensive individuals with either a non-dipper-type or a dipper-type circadian rhythm of blood pressure (BP). METHODS: A total of 103 patients were allocated into four groups as follows: (i) normotensive/dipper, n=28; (ii) normotensive/nondipper, n=26; (iii) hypertensive/dipper, n=25; and (iv) hypertensive/nondipper, n=24. The linear regression slopes of the QT interval measured to the apex and to the end of the T wave plotted against R-R intervals (QTapex/R-R and QTend/R-R slopes, respectively) were calculated from 24-h ambulatory ECG recordings using a dedicated algorithm. RESULTS: QTapex/R-R and QTend/R-R slopes were higher in the nondipper subgroup of normotensive cases with respect to the dipper subgroup of normotensive cases (QTapex/R-R=0.171±0.017 vs. 0.127±0.023, P=0.001; QTend/R-R=0.159±0.015 vs. 0.133±0.025, P=0.001). QTapex/R-R and QTend/R-R slopes were higher in the nondipper subgroup of hypertensive cases with respect to the dipper subgroup of hypertensive cases (QTapex/R-R=0.187±0.019 vs. 0.133±0.019, P=0.001; QTend/R-R=0.183±0.018 vs. 0.147±0.022, P=0.001). Pearson's correlation analyses revealed a higher negative correlation between night-time decline in BP and QTapex/R-R (r=-0.638, P=0.001). There was also a moderate negative correlation between night-time decline in BP and QTend/R-R (r=-0.504, P=0.001). The correlation coefficients for degree of night-time dipping and QT dynamicity indices were higher in hypertensive groups than in the normotensive groups. CONCLUSION: Blunting of the nocturnal fall in BP associates with impaired QT dynamicity indices in both normotensive and hypertensive groups.

Total white blood cell count is associated with the presence, severity and extent of coronary atherosclerosis detected by dual-source multislice computed tomographic coronary angiography.

BACKGROUND: Total white blood cell (WBC) count has been consistently shown to be an independent risk factor and predictor for future cardiovascular outcomes, regardless of disease status in coronary artery disease (CAD). The purpose of this study is to evaluate the relationship between total WBC count and the presence, severity and extent of coronary atherosclerosis detected in subjects undergoing multislice computed tomographic (MSCT) coronary angiography for suspected CAD. METHODS: A total of 817 patients were enrolled in this cross-sectional study. Non-significant coronary plaque was defined as lesions causing £ 50% luminal narrowing, and significant coronary plaque was defined as lesions causing 〉 50% luminal narrowing. For each segment, coronary atherosclerotic lesions were categorized as none, calcified, non-calcified and mixed. All images were interpreted immediately after scanning by an experienced radiologist. RESULTS: An association between hypertension, diabetes mellitus, age, gender, hyperlipidemia, smoking, total WBC counts and coronary atherosclerosis was found when patients were grouped into two categories according to the presence of coronary atherosclerosis (p 〈 0.05). Although plaque morphology was not associated with total WBC counts, the extent of coronary atherosclerosis was increased with higher total WBC quartiles (p = 0.006). Patients with critical luminal stenosis had higher levels of total WBC counts when compared to patients with non-critical luminal narrowing (7,982 ± 2,287 vs 7,184 ± 1,944, p 〈 0.05). CONCLUSIONS: Our study demonstrated that total WBC counts play an important role in inflammation and are associated with the presence, severity and extent of coronary atherosclerosis detected by MSCT. Further studies are needed to assess the true impact of WBC counts on coronary atherosclerosis, and to promote its use in predicting CAD.

Are the conventional cutoff values adequate to define hypertension in young women?

BACKGROUND: Women have lower systolic blood pressure (SBP) levels than men during early adulthood. Diastolic blood pressure (DBP) tends to be just marginally lower in women than men regardless of age. OBJECTIVE: Aims of this study were (i) to determine 95th percentile value of SBP, DBP, and mean arterial blood pressure in healthy women, and (ii) to evaluate the effects of basal demographic and anthropometric features on blood pressure. METHODS: Six hundred and fifty-four consecutive participants (18-35 years old) were initially enrolled in the study but among them 54 (8.2%) cases were excluded. Demographic features, relevant personal and family history data about hypertension, smoking habits, and use of medications were interviewed using a questionnaire. Blood pressure, height, weight, and waist circumference of every case were measured. RESULTS: Of the 600 patients (mean age, 24.6±4.0 years), 124 (20.7%) were currently smokers, 20 (3.3%) had history of hypertension during pregnancy, and 291 (48.5%) had family history of hypertension in women (mean age, 61.0±9.51 years). Reference ranges of 5th and 95th percentile values for SBP were determined as 74 and 115 mmHg, for mean arterial blood pressure as 57 and 85 mmHg, for DBP as 45 and 72 mmHg, respectively. CONCLUSION: In conclusion, cutoff values of hypertension in healthy women, which were determined by our study, are lower than the standard cutoff values for definition of hypertension in adults. However, clinical importance of these findings should be investigated in further studies involving larger population with prospective follow-up.