Meta‐Analysis of P‐Wave Dispersion Values in Healthy Individuals: The Influence of Clinical Characteristics

Background: P‐wave dispersion (Pd) is an appealing marker for predicting the risk of developing atrial fibrillation. At present, no definitive cutoff value has been determined as to the diagnosis of high‐risk patients. Our aims were to evaluate P‐wave parameters of healthy subjects published in the literature, determine normal range and weighted means of Pd and P‐wave parameters, and investigate the influences of gender, age, and BMI on the weighted results. Methods: A systematic search of studies published in PubMed was conducted. Only studies which included control groups of healthy individuals were included. Results: Of the 657 studies initially identified, 80 were eligible for inclusion. The total number of participants was 6,827. The highest reported Pd values were 58.56 ± 16.24  ms; the lowest were 7 ± 2.7  ms. The weighted mean was 33.46 ± 9.65  ms; weighted median was 32.2  ms. Gender and age were not found to be associated with significant influences on P‐wave parameter values. High‐normal BMI was not found to be associated with increased P‐wave parameter values. Conclusions: Pd, Pmax, and Pmin span a wide range of values in healthy individuals. Seemingly, abnormal values were often reported in healthy adults. The high variability of P‐wave parameters in healthy individuals, and overlapping of the results with those reported for patients with increased risk for atrial fibrillation, might suggest that this technique has limited sensitivity and specificity. The variability between studies may stem from methodological issues and, therefore, there is a definite need for methodological standardization of Pd measurements. Ann Noninvasive Electrocardiol 2012;17(1):28–35     

Vasospastic Angina with J‐Wave Pattern and Polymorphic Ventricular Tachycardia Effectively Treated with Quinidine

Background: Myocardial ischemia during coronary spasm may generate malignant ventricular arrhythmias. The J‐wave pattern was suggested to be a marker of a disorder associated with life‐threatening arrhythmias. Results: We report the case of a patient with vasospastic angina and J‐wave pattern in inferior and lateral leads associated with polymorphic ventricular tachycardia which was effectively treated only with quinidine—vasodilating drugs were not able to prevent the arrhythmia although they were effective in preventing ischemic events. Conclusion: The J‐wave pattern in inferolateral leads may be a sign of electrical vulnerability to lethal ventricular arrhythmia in patients suffering from vasospastic angina—quinidine can effectively prevent such arrhythmias in these patients.     

The Presence of Giant Epsilon Waves in a Patient with Arrhythmogenic Right Ventricular Cardiomyopathy

Epsilon wave, which is a major diagnosis criterion for arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD/C), is defined as small amplitude potentials. The present case is a 49‐year‐old man with a history of syncope and palpitations for 6 months. The ECG documented ventricular tachycardia (VT) when the patient has palpitations. However, there has been a giant epsilon wave in sinus rhythm. Electroanatomic mapping also has a prominent double potential identified on ABL catheter. The amplitude of epsilon wave reached 0.9 mV, which might be the maximum epsilon wave until now.     

Chemical Properties of Water-soluble Porphyrins. 4. The Reaction of A ‘Picket-fence-like’ Iron (III) Complex with the Superoxide Oxygen Couple

Summary

Solution properties of the iron-(III) ‘picket-fence-like’ porphyrin, Fe(III)-α,α,α,β-tetra-ortho (N-methyl-isonicotinamidophenyl) porphyrin, (Fe(III)PFP) were investigated. These were acid/base properties of the aquo complex with pK_a of 3·9 and its aggregation (formation of dimer with K = 1 × 10^?10 dm³ mol^?1), complex formation with cyanide ions and 1-methyl imidazole (1-MeIm), spectral properties of the three iron complexes in their ferric and ferrous form and the one-electron reduction potential of these complexes. Knowing these properties, the reaction of the ferric complexes, aquo, dicyano and bis (1-MeIm), with the superoxide radical and other reducing radicals were studied using the pulse radiolysis technique. The second-order reaction rate constant of O^?₂ with the iron (III) aquo complex which governs the catalytic efficiency of the metalloporphyrin upon the disproportionation of the superoxide radical was 7·6 × 10⁷ dm³ mol^?1 s^?1, two orders of magnitude faster when compared to the reaction of each of the other complexes. The reduction by other radicals with all iron (III) complexes had similar second-order rate constants (10⁹ to 10¹⁰ dm³ mol^?1 s^?1). The reduction reaction in all cases produced Fe(II)PFP and no intermediate was found. The oxidation reaction of Fe(II)PFP by O^?₂ was one order of magnitude faster when compared to the reduction of Fe(III)PFP by the same radical. Since the reactivity of O^?₂ toward the three iron (III) porphyrin complexes follows their reduction potentials, it is suggesting the formation of a peroxo Fe(II) porphyrin as an intermediate. The reactions of the Fe(II)PFP complexes with dioxygen were also studied. The aquo complex was found to be first order in O₂ and second order in Fe(II)PFP, suggesting the formation of a peroxo Fe(II) porphyrin as an intermediate. The intermediate formation was corroborated by evidence of the rapid CO binding reaction to the aquo complex of Fe(II)PFP. The two other complexes reacted very slowly with O₂ as well as with CO.     

Assessment of Arterial Stiffness in Female and Male Gout Patients

The aim of this study was to investigate the relationship between central blood pressures (BP), pulse wave velocity (PWV) meaurements, and biochemical parameters in female and male gout patients and controls. This study included 12 (23.5%) females and 39 (76.5%) males with gout disease. 24-hour diastolic BP, day diastolic BP and day diastolic exceeding limit value were higher in male gout patients than female gout patients. In male gout patients, more prominent inflammatory changes in the vascular wall may be an explanation for the result of this our study, because history of hypertension and smoking habits were frequent in this group.     

Investigation of the Aortic Pulse Wave Velocity in Patients with Gilbert’s Syndrome

Arterial stiffness is currently the “gold standard” measure of aortic (carotid-femoral) pulse wave velocity (PWV), which is an important independent predictor of risk of developing a cardiovascular event. Gilbert’s syndrome is a congenital disorder characterized by intermittent and non-hemolytic elevation of indirect bilirubin levels due to the deficiency of the enzyme UDP-glucuronyl transferase in the liver and many prospective studies found an inverse relationship between bilirubin levels and cardiovascular events in these patients. We aimed to investigate serum bilirubin levels and arterial stiffness parameters in patients with Gilbert’s syndrome in this study. A total of 53 cases, consisting of 26 patients with a diagnosis of Gilbert’s syndrome and 27 healthy control subjects, were included in the study. Serum bilirubin levels, other routine blood chemistry, and arterial stiffness measurements were recorded. The mean ages of Gilbert’s syndrome and the control group were 31.5 ± 9.7 and 36.8 ± 11.1 years, respectively. PWV measurements were significantly lower in Gilbert syndrome patients (6.68 and 7.3 m/s in patients and controls; respectively) (P < .05). In correlation analysis in Gilbert’s syndrome patients, PWV had a significant correlation with total and indirect bilirubin levels (r = ?0.370, P = .009/r = ?0.495, P = .003, respectively). Gilbert’s syndrome patients have lower PWV measurements compared to healthy subjects, and the total and indirect bilirubin levels are also associated with PWV measurements. These findings may indicate the decreased atherosclerotic disease incidence in Gilbert’s syndrome patients.     

骨不连治疗的研究与技术应用进展*

背景：骨不连是骨折晚期常见的临床问题,数十年来,在各种新式内外固定材料、普及的显微外科技术、创新的植骨材料,尤其是分子生物学技术的全面帮助下,骨不连的治疗取得了突破性进展。
　　目的：总结骨不连治疗的研究进展,为以后更好地治疗骨不连提供技术理论和方法选择。
　　方法：由第一作者运用计算机检索系统检索1990年1月至2013年5月发表的有关骨不连原因及治疗方法的文献,以“fracture nonunion,treatment,progress”或“骨不连,治疗方法,进展”为检索词。同一领域则选择近期发表或者发表在权威杂志的文章。
　　结果与结论：排除重复性研究及时间跨度大的文献,从检索结果中共选择了48篇文章进一步分析。骨不连治疗手段主要有两种：非手术方式和手术方式,目前临床上以手术方式为主且高效。骨折愈合是多环节参与的复杂过程,一旦骨不连发生,应具体问题具体分析,根据患者的实际情况采取个体化治疗原则,重视软组织的保护,必要时联合运用多种手术及非手术方法,才能取得满意的疗效。