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51.
AF Ablation in Patients With Valvular Heart Disease . Background: The purpose of this study is to evaluate the efficacy of atrial fibrillation (AF) ablation in patients with moderate valvular heart disease (VHD). Methods: In total, 534 consecutive patients who underwent AF ablation were enrolled. Patients with a history of valve surgery or other structural heart disease were excluded. Patients with clinically moderate VHD (group‐1, n = 45) were compared with those without VHD (control group‐2, n = 436). Ipsilateral pulmonary vein antrum isolation (PVAI) was performed with a double Lasso technique in all the patients. Left atrial (LA) linear ablation was undertaken in persistent AF patients, if AF was inducible after PVAI. Results: Patients in group‐1 were significantly older and had a larger LA. PVAI was successfully achieved in all the patients. Patients in group‐1 received LA linear ablation more frequently during the index procedure. After a median of 26 months from the index procedure, the freedom from AF was significantly lower in group‐1 than group‐2 off antiarrhythmic drugs (AADs) (47% vs 69%, P = 0.002). Although there were more number of total procedures in group‐1 than group‐2, the freedom from AF was lower at median 24 months after the last procedure (78% vs 87%, P = 0.038). There was no significant difference in the freedom from AF on AADs (91% vs 95%, P = 0.356) or complication rate between the 2 groups. Atrial tachycardia following the index procedure was observed more frequently in group‐1 (P = 0.001). Conclusion: The patients with VHD undergoing AF ablation are less likely to remain in sinus rhythm at long term without AADs than those without VHD. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1193‐1198, November 2010)  相似文献   
52.
Objectives: To compare three positions for defecation by measuring abdominal pressure and the anorectal angle simultaneously. Methods: We recruited six healthy volunteers. The videomanometric measures included simultaneous fluoroscopic images, abdominal pressures, subtracted rectal pressures and anal sphincter pressures. Three positions were used: sitting, sitting with the hip flexing at 60 ° with respect to the rest of the body, and squatting with the hip flexing at 22.5 ° with respect to the rest of the body. Results: Basal abdominal pressure before defecation on hip‐flex sitting was lower than that with normal sitting, although the difference did not reach statistical significance. Basal abdominal pressure before defecation on squatting (26 cmH2O) was lower than that with normal sitting (P < 0.01). Abdominal pressure increase (strain) on hip‐flex sitting was lower than that with normal sitting, although this difference did not reach statistical significance. Similarly, the abdominal pressure increase on squatting was smaller than that with normal sitting, and yet the difference did not reach statistical significance. The rectoanal angle on defecation on hip‐flex sitting did not differ from that with normal sitting. The rectoanal angle on defecation on squatting (126 °) was larger than that with normal sitting (100 °) (P < 0.05), and was also larger than that with hip‐flex sitting (99 °) (P < 0.01). Conclusion: The results of the present study suggest that the greater the hip flexion achieved by squatting, the straighter the rectoanal canal will be, and accordingly, less strain will be required for defecation.  相似文献   
53.
Background and objective: Several algorithms that predict the optimal CPAP have been developed for Caucasian patients with OSA syndrome, but these algorithms do not allow for racial differences in craniofacial anatomy. We investigated whether an equation that included data on craniofacial structure, physique and severity of OSA could more accurately predict the optimal CPAP for Japanese patients with OSA syndrome. Methods: In 170 Japanese patients with OSA syndrome, the optimal CPAP was determined by manual titration during polysomnography. An equation predicting the optimal pressure was derived from anthropometric, polysomnographic and cephalometric data. This equation was validated in another 110 Japanese patients with OSA syndrome. Results: Stepwise multiple regression analysis identified AHI, BMI, mean SaO2 and a cephalometric parameter: the angle between a line from point B to the menton (Me) and a line from Me to the hyoid bone (H) (BMeH), as independent predictors of optimal CPAP. The following equation was constructed to predict the optimal CPAP: 27.78 + (0.041 × BMeH) + (0.141 × BMI) + (0.040 × AHI) ? (0.312 × mean SaO2). This equation accounted for 47% of the variance in optimal pressure (R2 = 0.47, P < 0.0001). The measured optimal pressure and the pressure calculated using this equation were very similar in the other 110 patients with OSA syndrome (9.5 ± 3.0 and 9.2 ± 2.1 cmH2O, respectively). Conclusion: Optimal CPAP was more accurately predicted by combining a cephalometric parameter with BMI and polysomnographic data in Japanese patients with OSA, suggesting that craniofacial structure may be important in the pathogenesis of OSA syndrome among Asians.  相似文献   
54.
Coronary Vein Accessory Pathways. Introduction: Some posteroseptal accessory pathways (APs) can be successfully ablated by radiofrequency current only from inside the coronary sinus (CS) or its branches, because of an absolute or relatively epicardial location. The aim of this study was to identify ECG features of manifest posteroseptal APs requiring ablation in the CS or the middle cardiac veins (MCVs). Methods and Results: One hundred seventeen consecutive patients with manifest posteroseptal APs successfully ablated: (1) ≥ 1 cm deep inside the MCV (group MCV: n = 13); (2) inside the CS, including the area adjacent to the MCV ostium (group CS: n = 10); (3) at the right (group R: n = 60); or (4) the left posteroseptal endocardial region (group L: n = 34) were included. We reviewed delta wave polarity (initial 40 msec) and QRS morphology during sinus rhythm and atrial pacing as well as electrogram characteristics in these patients. The local target site electrogram in groups MCV and CS was characterized by a longer atrial to ventricular electrogram interval, suggesting a longer course of the pathway and more frequent recording of a presumptive AP potential compared to the group ablated at the right or left endocardium. The most sensitive ECG feature for group CS or group MCV was a negative delta wave in lead II in sinus rhythm (87%), but specificity (79%) and positive predictive value (50%) were relatively low. A steep positive delta wave in aVR during maximal preexcitation possessed the highest specificity and positive predictive value (98% and 88%, sensitivity 61%) which increased to 99% and 91%, respectively, when combined with a deep S wave in V6 (R wave ≤ S wave). Conclusion: These data suggest that posteroseptal APs ablated inside the coronary venous system have highly specific features, including the combination of a steep positive delta wave in lead aVR and a deep S wave in lead V6 (R wave ≤ S wave) during maximal preexcitation. The highest sensitivity is provided by a negative delta wave in lead II. These findings may be helpful for anticipating and planning an epicardial ablation strategy.  相似文献   
55.
56.
Objective: This study examined the relationship between bothersome symptoms of nocturia and erectile function. Methods: Subjects comprised patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). Patients were prospectively followed on treatment with the alpha‐1 blocker naftopidil for 8 weeks. Patient backgrounds and efficacy of naftopidil associated with LUTS and sexual activity were evaluated. Results: The percentage of patients who identified nocturia as the most bothersome symptom was 30.2% (n = 135), representing the highest percentage among International Prostate Symptom Score (IPSS) items. The number of patients with nocturia as the most bothersome symptom plateaued at an IPSS for nocturia of two or three points. In contrast, the number of patients with slow stream as the most bothersome symptom increased with symptom severity according to IPSS for slow stream. Logistic regression analysis on association between nocturia and erectile function confirmed that the odds ratio was 1.41 (P < 0.05). Naftopidil showed excellent efficacy related to male LUTS, but International Index of Erectile Function 5 (IIEF5) total score was almost unchanged. Among patients with nocturia improved by naftopidil, IIEF5 total score was significantly changed in the group with IPSS nocturia score ≤1 as compared to the group with IPSS nocturia score ≥2 per night (P = 0.038). Conclusion: Nocturia the most bothersome symptom correlated with aging. Nocturia could associate erectile dysfunction, and keeping the frequency of nocturia at ≤1 episode might be meaningful for maintaining quality of life in elderly men.  相似文献   
57.
58.
The clonogenic patterns of three human pulmonary adenocarcinomacell lines (PC-9, PC-13 and PC-l4) were studied by human tumorclonogenic assay (HTCA), and factors which could influence theresults of tests for the chemosensitivity of these tumor cellsto cisplatin in HTCA were determined. The results showed thateach tumor cell line had a characteristic clonogenic pattern.The time intervals for the cells to grow to the plateau phasevaried from 9 to 16 days, depending on the cell line and numberof cells plated. The number of cells plated could substantiallyinfluence the results of chemosensitivity tests. The percentageof surviving colonies increased markedly if too many cells (usually5 x 104 or more/plate) were plated. For continuous exposure,the results of chemosensitivity tests were rather stable after7 days of incubation in each cell line, especially when fewerthan 2 x 104 cells/plate were plated. For 1-hour exposure, theincubation periods for the results to become stable varied from7 to 16 days depending on the cell type, number of cells platedand drug concentration. It was stressed that for the correctevaluation of the chemosensitivity of cultured cell lines inHTCA, the clonogenic pattern of each tumor cell line shouldbe checked in detail before further experiments are conducted.The higher the concentration and the longer the exposure time,the more strongly cis-diamminedichloroplatinum (CDDP) suppressedthe colony growth in each of the three cell lines in HTCA, andit was recommended that CDDP should be used clinically in sucha way as to maintain a high serum level of the active form ofCDDP for a long time.  相似文献   
59.
Abstract  Four all-night polysomnograms of a 39-year-old male patient with non-24 h sleep-wake syndrome were recorded. We analysed electroencephalograms (EEG) with the power spectrum method and the wave pattern recognition analysis of Fujimori. The EEC of the rest waking condition showed normal patterns. High-voltage diffuse alpha band waves were observed in sleep stages 2, 3 and 4. The integrated area of the alpha band waves in the analysis epochs showed a strong positive correlation to the delta hand components in the power spectrum of the same epoch during sleep (correlation coefficients r = 0.762–0.815). Alpha hand waves during sleep were clearly different from the alpha waves in the rest waking condition, with respect to slower peak frequency and the frontal dominant voltage distribution.  相似文献   
60.
Little is known about the plasma concentrations of cyclic 3',5'-guanosine monophosphate (cGMP) in patients with cirrhosis. However, plasma cGMP concentrations provide information on cellular cGMP production by particulate guanylyl cyclases (which are stimulated by natriuretic peptides, such as atrial natriuretic peptide; ANP). In contrast, because intracellular cGMP elicits vasorelaxant mechanisms, plasma cGMP concentrations may be related to haemodynamic alterations in patients with cirrhosis. The aim of the present study was to measure plasma cGMP concentrations in patients with cirrhosis and controls and to examine the relationship between cGMP levels and plasma ANP concentrations and haemodynamic values. Plasma concentrations of cGMP and ANP and splanchnic and systemic haemodynamics were measured in 23 subjects; 13 subjects had cirrhosis and 10 were controls. All subjects had normal glomerular filtration. Plasma cGMP concentrations were significantly higher in patients (6.5±0.8 pmol/mL) than in controls (2.7±0.4 pmol/mL), while plasma ANP concentrations did not significantly differ between the two groups (127±22 and 123±27 pg/mL, respectively). In patients with cirrhosis, no significant correlation was found between plasma cGMP concentrations and plasma ANP concentrations, hepatic venous pressure gradient, cardiac output or systemic vascular resistance. In conclusion, in patients with cirrhosis, increased plasma cGMP concentrations may be due to an activation of particulate guanylyl cyclases by natriuretic peptides other than ANP. The present study suggests that plasma cGMP concentrations are not related to cirrhosis-induced haemodynamic alterations.  相似文献   
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