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Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
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对不孕症患者进行碘化油输卵管造影检查是临床上经常需要做的一种检查,以往施行输卵管碘化油造影是在X线照射下,由于造影需要时间较长,医患双方都会接受大量X线照射,不利于身体健康。我院自2002年1月~2003年3月,对30例不孕症患者,利用B超经腹壁,在实时观察引导下行碘化油输卵管造影术,现总结报告如下。1材料与方法本组患者年龄在25~45岁,均经临床妇科检查及B超常规检查,经输卵管通液及药物治疗无效者。其中原发不孕5例,继发不孕25例。采用东芝公司的SSH-140A型超声诊断仪,探头频率3·75MHz。窥阴器、宫颈钳、宫颈导管、20ml或30ml注射器… 相似文献
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Jorge Polónia Jo?o Maldonado Rui Ramos Susana Bertoquini Mary Duro Cristina Almeida Jo?o Ferreira Loide Barbosa José Alberto Silva Luís Martins 《Revista portuguesa de cardiologia》2006,25(9):801-817
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events. 相似文献
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Rui Providência 《Revista portuguesa de cardiologia》2006,25(11):1043-1058
This article discusses the cardiovascular protection afforded by low to moderate consumption of ethanol and the role of ethanol-induced preconditioning. Ethanol, a compound that is found in many popular beverages, has a whole range of cardiovascular protective effects when consumed in low to moderate doses. Although they have yet to be totally clarified, recent data suggest that a combination of several actions at the biochemical and molecular levels play a role in this protection. These include favorable changes in lipid metabolism, antioxidant effects, changes in hemostasis and platelet aggregation, arterial vasodilation mediated by NO release, induction of the expression of cardioprotective proteins, insulin sensitization and lower levels of inflammatory markers. Special emphasis will be given to ethanol-induced preconditioning. Some of the compounds present in red and white wine, such as resveratrol and quercetin, are also partly responsible for some of the cardioprotective effects of alcoholic drinks. These are due to antioxidant effects and changes in platelet aggregation, endothelial function and inflammatory response. The last part of the paper will focus on the clinical applications and possibilities raised by these new findings. 相似文献
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98例尿道下裂手术的体会 总被引:1,自引:0,他引:1
目的通过对尿道下裂手术的改进,进一步完善尿道下裂手术的技巧和护理。方法A组50例尿道下裂Ⅰ期成形术中,采用皮下连续内翻缝合形成新尿道,且固定于阴茎海绵体,由阴茎根部自下而上多层次,多点缝合皮瓣皮下组织至阴茎海绵体上,均无间隙和死腔。B组48例采用常规手术方式作对照。结果A组50例尿道下裂Ⅰ期成形术成功44例,B组48例成功17例,A组与B组相比成功率显著提高(P<0.05)。结论尿道下裂Ⅰ期成形术成功率关键在于术者对术式掌握的熟练程度和术中及术后对每个细节的认真处理。 相似文献
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中国急性心肌梗塞的疾病经济负担 总被引:8,自引:1,他引:7
主要通过对急性心肌梗塞疾病经济负担的研究,总体描述进行二线预防的重要性。资料主要来源于中文文献检索、政府统计报表。主要利用直接医疗费用来计算疾病经济负担,而未考虑直接非医疗费用和间接费用。中日急性心肌梗塞的发病率约为45/10万。55/10万。城市高于农村,男性高于女性。在2000年,急性心肌梗塞的死亡率在城市为32.39/10万,农村为17.99/10万,其死亡率随年龄增长而相应增长。与发病率一样,城市高于农村,男性高于女性。25岁以上人群因急性心肌梗塞而损失的DALY在2000年为3.57DALYs/千人口。怎性心肌梗塞的直接医疗费用在国家卫生部部属医院为28257元/例,省级医院为8663元/例,县级医院为5447无/例。测算2000年急性心肌梗塞的疾病经济负担为13亿元。19亿元。但由于只有10.6%的急性心肌梗塞病人得到临床床治疗,因此,本测算结果可能低估了在中国实际发生的疾病经济负担。 相似文献