Effects of P-wave dispersion on atrial fibrillation in patients with acute anterior wall myocardial infarction

Backround: P‐wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P‐wave duration (P minimum), and maximum P‐wave duration (P maximum) have been used to evaluate the discontinuous propagation of sinus impulse and the prolongation of atrial conduction time respectively. The aim of this study was to investigate whether early assessment of P dispersion predicts paroxysmal atrial fibrillation (AF) in patients with acute anterior wall myocardial infarction (MI). Methods: We prospectively evaluated 147 consecutive patients (45 women, 102 men; aged 55 ± 9 years) with a first acute anterior wall MI. All patients were evaluated by echocardiography to measure the left atrial diameter and left ventricular ejection fraction (LVEF). Electrocardiography was recorded from all patients on admission and every day during hospitalization. Results: AF occurred in 25 patients. In 122 patients, AF did not occur. P maximum was found to be significantly higher in patients with AF than in patients without AF (115 ± 17.3 ms vs 101 ± 14.7 ms, P = 0.001 ). P dispersion also was significantly higher in patients with AF than in patients without AF (50 ± 12.5 ms vs 43 ± 10.1 ms, P = 0.01 ). There was no significant difference between the two groups in P minimum (64 ± 12.5 ms vs 59 ± 11.7 ms, P = 0.057 ). The echocardiographically left atrial diameters were not significantly higher in the patients with AF than those without (25 ± 3.38 mm and 23 ± 3.36 mm , respectively, P = 0.76 ). LVEF was found to be significantly different in the patients who developed AF and in those who did not (37.96 ± 6.18% vs 47.70 ± 6.01%, P = 0.0001 ). Conclusions: Although P maximum and P dispersion are significant predictive factors of AF in patients with acute anterior wall MI in the univariate analysis, on the basis of multivariate analysis, only age and LVEF were independent predictive parameters for AF.     

Left Ventricular Dyssynchrony and Its Effects on Cardiac Function in Patients with Newly Diagnosed Hypertension

Objectives: Left ventricular (LV) systolic synchrony, defined as simultaneous peak contractions of corresponding cardiac segments, is well documented to be impaired in hypertension but its effect on LV function is not clear. The aim of this study was to assess the impacts of LV systolic dyssynchrony on LV function in newly diagnosed hypertensives. Methods: Forty-eight newly diagnosed hypertensive patients and 33 controls were enrolled. All study population underwent a comprehensive echocardiographic evaluation including tissue synchrony imaging. The time to regional peak systolic tissue velocity (Ts) in LV by 12 segmental models was measured and two parameters of systolic dyssynchrony were computed. Results: Baseline demographic characteristics were similar in both study groups. Dyssynchrony parameters prolonged in newly diagnosed hypertensive patients compared to controls: the standard deviation (SD) of 12 LV segments Ts (40.2 ± 21 vs. 26.2 ± 13.4, P = 0.003); the maximal difference in Ts between any 2 of 12 LV segments (123.3 ± 61.5 vs. 79.8 ± 37.9, P = 0.001). In multivariable analysis, Ts-SD-12 was found to be an independent predictor for systolic function (β=-0.29, P = 0.008). But, both diastolic and global functions were not independently related to Ts-SD-12. Conclusion: LV synchronization is impaired in newly diagnosed hypertensive patients. LV dyssynchrony is one of the independent predictors of systolic function in hypertensive patients.     

Endoscopic Management of Barrett’s Esophagus: Advances in Endoscopic Techniques

Barrett??s esophagus (BE) is a well-known premalignant condition that can be associated with the development of dysplasia and adenocarcinoma. In the past, esophagectomy was the standard treatment for patients with BE with high grade dysplasia (HGD) and early cancer (EC). However, esophagectomy is not necessarily the only treatment response to HGD and EC anymore. Over the past decade, a number of endoscopic therapies have been developed for management of BE. These include endoscopic mucosal resection, thermal ablation techniques that use laser irradiation, multipolar electrocoagulation, argon plasma coagulation, photodynamic therapy, and the recently developed cryotherapy and radiofrequency ablation.     

Electrophysiological correlates of sensory innervation of the vesico-urethral junction and urethra in man

To investigate urethral sensory innervation in man, cerebral evoked potentials (CEPs) and bulbocavernous reflex (BCR) were recorded by stimulation of vesico-urethral junction (VUJ), prostatic and distal urethra, and penile skin. A specially produced catheter with a pair of electrodes was used for bipolar stimulation along the lower urinary tract. In comparison to the potentials evoked by distal urethral stimulation, the shape differences and protracted latency of CEPs to VUJ stimulation suggest that the distal and proximal urethra are innervated by different peripheral afferents. Similarities of CEPs and BCR latencies produced by prostatic urethral and VUJ stimulation indicate that the sensory innervation of the prostatic urethra is provided by pelvic nerve afferents. The remaining distal parts of the urethra are innervated by pudendal nerves. This is indicated by shape similarities and latency characteristics of both CEPs and BCR when the distal urethra and glans skin are stimulated.     

Hippocampal abnormalities associated with various congenital malformations

Objective  Our objective in this retrospective study was to assess the hippocampal abnormalities, associate them with various congenital brain malformations, and define the frequency of the association in specific anomaly subgroups. Methods  A total of 62 patients with congenital malformations of the brain who had thin-slice coronal T2-weighted, fluid attenuated inversion recovery, IR, or T1-weighted 3D gradient echo images were retrospectively evaluated for the type of congenital brain malformation and morphological or rotational hippocampal abnormalities. Medical records were reviewed for age, sex, and symptoms. Conclusion  Hippocampal abnormalities are found in 55.8% of all patients with different kinds of congenital brain malformations that are mostly associated with cortical dysplasia, lissencephaly, and total agenesis of the corpus callosum. The severity of the injury may have an effect on the extent of the involvement of the brain.     

Comparison and evaluation of experimental mediastinitis models: precolonized foreign body implants and bacterial suspension inoculation seems promising

Background  

Post-sternotomy mediastinitis (PSM) is a devastating surgical complication affecting 1–3% of patients that undergo cardiac surgery. Staphylococcus aureus is one of the most commonly encountered bacterial pathogen cultured from mediastinal samples obtained from patients with PSM. A component of the membrane of the gram positive bacteria, lipoteichoic acid, stimulates the blood monocytes and macrophages to secrete cytokines, radicals and nitrogen species leading to oxido-inflammatory damage. This seems to be responsible for the high mortality rate in PSM. For the evaluation of the pathogenesis of infection or for the investigation of alternative treatment models in infection, no standard model of mediastinitis seems to be available. In this study, we evaluated four mediastinitis models in rats.     

Aortic valve calcification: its significance and limitation as a marker for coronary artery disease

Aortic valve calcification (AVC) is correlated with atherosclerotic risk factors; however, its significance remains largely unknown. The aim of this study was to investigate whether AVC detected by transthoracic echocardiography can be a useful marker for the identification of significant coronary artery disease (CAD), particularly in elderly patients. The study included 432 consecutive patients with suspected CAD who were admitted for the first time for coronary angiography. Two-dimensional transthoracic echocardiography and selective coronary angiography were performed in all patients. Aortic valve calcification was defined as bright dense echoes of > 1 mm on one or more cusps and decreased mobility of the involved cusp. Aortic valve calcification was detected in 64 of the 337 patients with significant CAD, but only in 9 of 95 cases with normal or mildly stenotic coronary arteries (19% vs 9%, p < 0.001). The severity of coronary artery disease (defined as the number of obstructed vessels) was not related to the presence of AVC (p > 0.05). Stepwise multiple logistic regression analysis of the study patients revealed only age (p=0.003, odds ratio= 1.56) and AVC (p<0.001, odds ratio = 2.03) as independent predictors of CAD. When the study population was divided into two groups as those below (n = 338) and above (n = 94) 75 years old, AVC failed to be a predictor of CAD in those >75 years old (p > 0.05, odds ratio = 0.8) while it remained the most significant predictor of CAD (p<0.001, odds ratio=2.19 in patients aged <75 years. In conclusion, detection of AVC by transthoracic echocardiography may be a useful noninvasive marker for identification of significant CAD in patients younger than 75 years old. Its clinical usefulness is limited in elderly patients.