The Relationship Between Endocardial Voltage and Regional Volume in Electroanatomical Remodeled Left Atria in Patients with Atrial Fibrillation: Comparison of Three‐Dimensional Computed Tomographic Images and Voltage Mapping

Background: Long‐standing atrial fibrillation (AF) changes left atrial (LA) morphology, and the LA size is related to recurrence after radiofrequency catheter ablation (RFCA). We hypothesize that LA morphology, based on embryological origin, affects the outcome of RFCA. Methods: We analyzed 3D computed tomographic (CT) images of LA in 70 patients with AF (54 males, 55.6 ± 10.5 years old, paroxysmal AF (PAF):persistent AF (PeAF) = 32:38) who underwent RFCA. Each LA image was divided into venous atrium (VA), anterior LA (ALA), LA appendage (LAA), and both antrum. Absolute and relative volumes were calculated, and the lengths of linear ablation sites were measured. Results: (1) In patients with the mean LA voltage ≤ 2.0 mV, LA volume, especially ALA, was larger (P < 0.01) compared to those with LA voltage > 2.0 mV. (2) The total LA volume was significantly larger (P < 0.01) and LAA voltages (P < 0.05) and conduction velocities (P < 0.05) were lower in patients with PeAF than in those with PAF. (3) In patients with recurrence, LA volume was generally larger (P < 0.01) than in those without recurrence. In PAF patients with recurrence, the relative volume of ALA was significantly larger (P < 0.01) than those without recurrence. Conclusions Morphologically remodeled LA has low endocardial voltage, and enlargement of ALA is more significant in electroanatomically remodeled LA. The disproportional enlargement of ALA was observed more often in PAF patients with recurrence after ablation than those without recurrence.     

Mean platelet volume in patients with polycystic ovary disease

Platelets contribute to blood coagulation at sites of vascular injury and to the recruitment of leukocytes at sites of inflammation. Under pathological conditions, platelets are involved in numerous diseases and clinical complications, such as deep venous thrombosis, embolism and atherosclerosis. But so far, little is known about the mechanisms of inflammation in large veins and the role of platelets in inflamed large veins. For this purpose, we investigated primary and secondary interactions between platelets, leukocytes and endothelial cells in the femoral vein in vivo with special regard to the role of CD62P (P-selectin) and CD162 (PSGL-1). Mice were challenged with lipopolysaccharide (LPS)/D-galactosamine (D-gal) and either CD162 or CD62P was blocked by intravenous administration of a corresponding antibody at the time point of LPS/D-gal injection. Four hours after LPS/gal injection, intravital fluorescence microscopy of the femoral vein was performed and primary and secondary platelet-leukocyte-endothelial cell-interactions were visualized after in vivo platelet and leukocyte staining with rhodamine 6G. Analysis of intravital fluorescence microscopy revealed that LPS/D-gal caused a strong inflammatory reaction of the venous endothelium with significant induction of platelet and leukocyte tethering, rolling and adhesion. Secondary interactions of platelets to adherent or rolling platelets or leukocytes were also increased after LPS/D-gal-injection. Immunoneutralization of either CD162 or CD62P significantly decreased platelet primary and secondary capture as well as leukocyte rolling and adhesion. CD162 and CD62P play a central role in mediating inflammatory primary and secondary interactions of platelets and leukocytes to the endothelium in inflamed large veins in vivo. Thus, blocking CD162 or CD62P might be an attractive tool for preventing platelet and leukocyte-driven venous diseases.     

Metformin and oral contraceptive treatments reduced circulating asymmetric dimethylarginine (ADMA) levels in patients with polycystic ovary syndrome (PCOS)

There is a little information in literature about circulating asymmetric dimethylarginine (ADMA) concentrations in polycystic ovary syndrome (PCOS) and the results reported are discrepant. In this study, therefore, we aimed (1) to determine the circulating ADMA concentrations in 44 women with PCOS and 22 age- and BMI-matched healthy controls, (2) to evaluate its correlations with insulin resistance, gonadotrophins, and androgen secretion, and (3) to compare effects of metformin and ethinyl estradiol-cyproterone acetate (EE/CPA) treatments on circulating ADMA concentrations. In conclusion, our data indicate that circulating ADMA concentrations in non-obese, non-hypertensive and young women with PCOS are significantly higher than healthy controls and they improved by a 3-month course of metformin and oral contraceptive treatments.     

Cerebrospinal fluid superoxide dismutase and serum malondialdehyde levels in patients with aneurysmal subarachnoid hemorrhage: preliminary results

OBJECTIVES: Experimental studies provide evidence that oxidative damage plays a role in the development of vasospasm after aneurysmal subarachnoid hemorrhage (SAH) but data from human studies is still limited. The purpose of this study was to investigate the time course of cerebrospinal fluid (CSF) superoxide dismutase (SOD) and serum malondialdehyde (MDA) changes in patients with aneurysmal SAH. METHODS: SOD in CSF and MDA in the serum were detected on days 1-3, 5 and 7 after aneurysmal SAH in 21 patients, and the results were compared with 15 patients with hydrocephalus. The results were also compared with those of clinical parameters including the patient's outcome at 6 months. RESULTS: The mean CSF SOD levels were lower and serum MDA levels were higher than the controls. Patients with a high amount of blood within the cisterns had a trend to decreased SOD while increasing MDA levels. CONCLUSION: These preliminary results suggest that the levels of antioxidants are decreased after the onset of SAH in the early period, possibly because of increased oxidative stress. Reactive oxygen-mediated oxidative damage may play an important role in inflammation after SAH.     

Interrelationship between noninvasive predictors of atherosclerosis: transthoracic coronary flow reserve, flow-mediated dilation, carotid intima-media thickness, aortic stiffness, aortic distensibility, elastic modulus, and brachial artery diameter

BACKGROUND: In this study, we searched for a correlation between transthoracic coronary flow reserve (CFR) and well-established surrogates of coronary atherosclerosis. METHODS: The study was conducted on 136 healthy subjects (mean age: 39.9 +/- 7.3 years) who were free of coronary risk factors. Transthoracic echocardiography was used to measure the aortic stiffness index (AoSI), aortic distensibility (AoD), and aortic elastic modulus (AoEM). High-resolution ultrasound was used to measure brachial artery endothelium-dependent and independent vasomotion and carotid intima-media thickness (IMT). In addition, transthoracic second harmonic Doppler echocardiography was used to measure CFR. RESULTS: All of the parameters significantly correlated with each other except brachial endothelium-independent dilation. CFR correlated significantly with brachial endothelium-dependent dilation (EDD) (r = 0.302, P < 0.01), carotid IMT (r =-0.388, P < 0.01), brachial artery diameter (r = 0.340, P < 0.01), AoD (r = 0.275, P < 0.01), AoS (r =-0.299, P < 0.01), and AoEM (r =-0.30,7 P < 0.01). Carotid IMT correlated significantly with brachial EDD and modestly with brachial artery diameter, AoD, AoS, and AoEM.In multivariate analysis, carotid IMT (beta=-0.323, P < 0.0001) and brachial artery diameter (beta = -0.259, P = 0.001) were significant independent predictors of CFR. The left ventricular mass index (beta= 0.371, P < 0.0001), brachial EDD (beta = -0.232, P = 0.002), and CFR (beta = -0.228, P = 0.003) were significant predictors for IMT. CONCLUSION: Transthoracic CFR correlated significantly with well-established noninvasive predictors of atherosclerosis, and we suggest that it can be used as a surrogate for coronary atherosclerosis.     

Adjunctive radiofrequency ablation of metastatic neuroendocrine cancer to the liver complements surgical resection

Background:

Resection of liver metastases from neuroendocrine cancer (NEC) prolongs survival and provides durable symptom relief. Not all hepatic lesions are amenable to resection, particularly when there is multifocal involvement. In this study, it was hypothesized that ablation of concomitant non-resectable NEC liver metastases is safe and salvages patients who would not have been selected for cytoreductive surgery.

Methods:

Patients who underwent adjuvant ablation of NEC liver metastases between 1995 and 2008 were reviewed. NEC was classified by patient and tumour characteristics. Regression and Kaplan–Meier models were used to compare variables and generate survival curves.

Results:

Ninety-four patients underwent hepatic resection and intra-operative ablation of metastatic NEC. The median number of lesions ablated was 3, and median size was 1.4 cm. One abscess occurred at an ablation site. Local recurrence was detected in four patients (3.8%). Overall survival was 80% and 59% at 5 and 10 years. Age, gender, tumour type, grade, primary site and need for repeat ablation had no significant association with survival. The Ki67 proliferative index was a significant predictor of decreased survival. Symptom-free survival was 34% at 3 years and 16% at 5 years, independent of the tumour grade.

Conclusion:

Concurrent ablation of NEC metastases to the liver not amenable to resection is safe and increases the candidacy of patients for cytoreductive surgery. Ablation performed intra-operatively and repeated post-operatively as needed provides significant symptom control regardless of the tumour grade.     

Volumetric evaluation of the relations among the cerebrum,cerebellum and brain stem in young subjects: a combination of stereology and magnetic resonance imaging

The Cavalieri estimator using a point grid is used to estimate the volume of three-dimensional structures based on two-dimensional slices of the object. The size of the components of intracranial neural structures should have proportional relations among them. The volume fraction approach of stereological methods provides information about volumetric relations of the components of structures. The purpose of our study is to estimate the volume and volume fraction data related to the cerebrum, cerebellum and brain stem. In this study, volume of the total brain, cerebrum, cerebellum and brain stem were estimated in 24 young Turkish volunteers (12 males and 12 females) who are free of any neurological symptoms and signs. The volume and volume fraction of the total brain, cerebrum, cerebellum and brain stem were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods. The mean (+/-SD) total brain, cerebrum and cerebellum volumes were 1,202.05 +/- 103.51, 1,143.65 +/- 106.25 cm(3) in males and females, 1,060.0 +/- 94.6, 1,008.9 +/- 104.3 cm(3 )in males and females, 117.75 +/- 10.7, 111.83 +/- 8.0 cm(3) in males and females, respectively. The mean brain stem volumes were 24.3 +/- 2.89, 22.9 +/- 4.49 cm(3) in males and females, respectively. Our results revealed that female subjects have less cerebral, cerebellar and brain stem volumes compared to males, although there was no statistically significant difference between genders (P > 0.05). The volume ratio of the cerebrum to total brain volume (TBV), cerebellum to TBV and brain stem to TBV were 88.16 and 88.13% in males and females, 9.8 and 9.8% in males and females, 2.03 and 2.03% in males and females, respectively. The volume ratio of the cerebellum to cerebrum, brain stem to cerebrum and brain stem to cerebellum were 11.12 and 11.16% in males and females, 2.30 and 2.31% in males and females, 20.7 and 20.6% in males and females, respectively. The difference between the genders was not statistically significant (P > 0.05). Our results revealed that the volumetric composition of the cerebrum, cerebellum and brain stem does not show sexual dimorphism.