The Association between Whole Blood Viscosity and Coronary Collateral Circulation in Patients with Chronic Total Occlusion

BACKGROUND AND OBJECTIVES: Coronary collateral circulation (CCC) has been attributed as inborn bypass mechanisms supporting ischemic myocardium. Various factors have been postulated in CCC. Whole blood viscosity (WBV) has been an underappreciated entity despite close relationships between multiple cardiovascular diseases. WBV can be calculated with a validated equation from hematocrit and total plasma protein levels for a low and high shear rate. On the grounds, we aimed to evaluate the association between WBV and CCC in patients with chronic total occlusion. SUBJECTS AND METHODS: A total of 371 patients diagnosed as having at least one major, chronic total occluded coronary artery were included. 197 patients with good CCC (Rentrop 2 and 3) composed the patient group. The poor collateral group consisted of 174 patients (Rentrop grade 0 and 1). RESULTS: Patients with poor CCC had higher WBV values for a low-shear rate (LSR) (69.5±8.7 vs. 60.1±9.8, p<0.001) and high-shear rate (HSR) (17.0±2.0 vs. 16.4±1.8, p<0.001) than the good collateral group. Correlation analysis demonstrated a significant negative correlation between the grade of CCC and WBV for LSR (β=0.597, p<0.001) and HSR (β=0.494, p<0.001). WBV for LSR (β=0.476, p<0.001) and HSR (β=0.407, p<0.001) had a significant correlation with the synergy between percutaneous coronary intervention with taxus and cardiac surgery (SYNTAX) score. A multivariate analysis showed that the WBV for both shear rates were independent risk factors of poor CCC (WBV at LSR, OR: 1.362 CI 95%: 1.095-1.741 p<0.001 and WBV at HSR, 1.251 CI 95%: 1.180-1.347 p<0.001). CONCLUSION: WBV has been demonstrated as the overlooked predictor of poor coronary collateralization. WBV seemed to be associated with microvascular perfusion and angiogenesis process impairing CCC development.

The Association between Platelet/Lymphocyte Ratio and Coronary Artery Disease Severity in Asymptomatic Low Ejection Fraction Patients

BACKGROUND AND OBJECTIVES: Coronary angiography (CAG) is generally needed in the setting of systolic heart failure (HF) with an unidentified etiology as a part of diagnostic strategy. On the other hand, the clinical value of this invasive strategy is largely unknown. Platelet-lymphocyte ratio (PLR) has recently emerged as a novel inflammatory index that may serve as an important predictor of inflammatory state and overall mortality. The present study aimed to search the predictive value of PLR in determining the extent of coronary atherosclerosis in asymptomatic low ejection fraction (EF) patients. SUBJECTS AND METHODS: 156 asymptomatic heart failure (HF) subjects (without angina or HF symptoms, mean age: 58 years; to male: 71.2%) were enrolled, and thereafter a CAG was performed. Gensini Score was used to determine the severity of coronary artery disease (CAD) on CAG. According to this scoring system, the overall study group was categorized into three distinct subgroups: control group with the score 0, mild atherosclerosis group with the score 0 to 20 and severe atherosclerosis group with the score of >20. Thereafter, a comparison was made among groups with regard to mean values of PLR. RESULTS: The severe atherosclerosis group had a substantially higher level of mean PLR in comparison to other groups (p<0.001). Pre-CAG PLR levels as well as a variety of clinical variables including age, low density lipoprotein (LDL)-cholesterol demonstrated an independent correlation with Gensini score through a multivariate analysis. CONCLUSION: These findings suggest the potential association of high PLR levels with severe atherosclerosis in the setting of asymptomatic systolic HF. A simple measurement of PLR helps to identify the severity of coronary atherosclerosis prior to conducting coronary angiography.

Diabetic Cardiomyopathy; Summary of 41 years

Patients with diabetes have an increased risk for development of cardiomyopathy, even in the absence of well known risk factors like coronary artery disease and hypertension. Diabetic cardiomyopathy was first recognized approximately four decades ago. To date, several pathophysiological mechanisms thought to be responsible for this new entity have also been recognized. In the presence of hyperglycemia, non-enzymatic glycosylation of several proteins, reactive oxygen species formation, and fibrosis lead to impairment of cardiac contractile functions. Impaired calcium handling, increased fatty acid oxidation, and increased neurohormonal activation also contribute to this process. Demonstration of left ventricular hypertrophy, early diastolic and late systolic dysfunction by sensitive techniques, help us to diagnose diabetic cardiomyopathy. Traditional treatment of heart failure is beneficial in diabetic cardiomyopathy, but specific strategies for prevention or treatment of cardiac dysfunction in diabetic patients has not been clarified yet. In this review we will discuss clinical and experimental studies focused on pathophysiology of diabetic cardiomyopathy, and summarize diagnostic and therapeutic approaches developed towards this entity.

The Presence of Fragmented QRS on 12-Lead Electrocardiography in Patients with Coronary Artery Ectasia

BACKGROUND AND OBJECTIVES: Coronary artery ectasia (CAE) is an angiographic finding characterized by dilation of an arterial segment with a diameter at least 1.5 times that of its adjacent normal coronary artery. Fragmented QRS (fQRS) complexes are electrocardiographic signals which reflect altered ventricular conduction around regions of a myocardial scar and/or ischaemia. In the present study, we aimed to evaluate the presence of fQRS in patients with CAE. SUBJECTS AND METHODS: The study population included 100 patients with isolated CAE without coronary artery disease (CAD) and 80 angiographically normal controls. fQRS was defined as the presence of an additional R wave or notching of R or S wave or the presence of fragmentation in two contiguous leads corresponding to a major coronary artery territory. RESULTS: The two groups were similar in terms of age, sex, hypertension, dyslipidemia, and family history of CAD. The presence of fQRS was significantly (p<0.05) higher in the CAE group than that in the normal coronary artery group (29% vs. 6.2%, p=0.008). Isolated CAE were detected most commonly in the right coronary artery (61%), followed by left anterior descending artery (52%), left circumflex artery (36%), and left main artery (9%). Multivariate stepwise logistic regression analysis showed that CAE {odds ratio (OR) 1.412; 95% confidence interval (CI) 1.085-1.541; p=0.003} and diabetes (OR 1.310; 95% CI 1.025-1.482; p=0.041) were independently associated with fQRS. CONCLUSION: The presence of fragmented QRS associated with increased risk for arrhythmias and cardiovascular mortality was significantly higher in patients with CAE than in patient with normal coronary artery. Further studies are needed to determine whether the presence of fragmented QRS is a possible new risk factor for patients with CAE.

Heart rate profile during exercise in patients with early repolarization / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Both early repolarization and altered heart rate profile are associated with sudden death. In this study, we aimed to demonstrate an association between early repolarization and heart rate profile during exercise.</p><p><b>METHODS</b>A total of 84 subjects were included in the study. Comparable 44 subjects with early repolarization and 40 subjects with normal electrocardiogram underwent exercise stress testing. Resting heart rate, maximum heart rate, heart rate increment and decrement were analyzed.</p><p><b>RESULTS</b>Both groups were comparable for baseline characteristics including resting heart rate. Maximum heart rate, heart rate increment and heart rate decrement of the subjects in early repolarization group had significantly decreased maximum heart rate, heart rate increment and heart rate decrement compared to control group (all P < 0.05). The lower heart rate increment (< 106 beats/min) and heart rate decrement (< 95 beats/min) were significantly associated with the presence of early repolarization. After adjustment for age and sex, the multiple-adjusted OR of the risk of presence of early repolarization was 2.98 (95%CI 1.21-7.34) (P = 0.018) and 7.73 (95%CI 2.84-21.03) (P < 0.001) for the lower heart rate increment and heart rate decrement compared to higher levels, respectively.</p><p><b>CONCLUSIONS</b>Subjects with early repolarization have altered heart rate profile during exercise compared to control subjects. This can be related to sudden death.</p>