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991.
A 15-fold increase in the prevalence of ankylosing spondylitis in a group of 223 men with permanent cardiac pacemakers has recently been demonstrated. In this study of the same patient group, the prevalence of other related rheumatic syndromes was investigated by clinical examination and HLA typing. The clinical picture and electrocardiographic features of all patients with HLA B27-associated rheumatic disease (seronegative spondarthritis) were analyzed. Altogether 28 patients, 12.6 percent (95 percent confidence limits: 8.2 to 17.0 percent), fulfilled inclusion criteria for seronegative spondarthritides; 15 had ankylosing spondylitis. The seronegative spondarthritides previously had been diagnosed in less than 50 percent of the patients. Twenty-two (85 percent) of the 26 HLA-typed patients were B27-positive, implying a very strong association with this genetically determined cell surface protein. Patients with severe bradyarrhythmias associated with the seronegative spondarthritides were thus found to constitute a large proportion of the 223 men with permanent pacemakers. A high frequency of aortic regurgitation and all kinds of bradyarrhythmias were found. Twenty patients had complete heart block--in a majority, occurring intermittently, but otherwise without distinguishing features.  相似文献   
992.
The catecholamines exert a positive inotropic effect associated with elevated tissue cyclic AMP levels and possibly with increase in the number of membrane slow cationic channels available for voltage activation. In the present study, catecholamines (isoproterenol, dopamine and dobutamine) were tested for their ability to affect the maximum upstroke velocity (+ Vmax) of the slow action potentials, the first derivative (dTdt) of developed tension accompanying the slow responses, and the tissue cyclic AMP levels in the ventricular myocardium of isolated perfused chick hearts. To study the slow channels exclusively, the fast Na+ channels were voltage inactivated by elevated (25 mm) K+. In this condition of functional removal of the fast channels, the heart could not be excited by intense electrical stimulation. It was found that these catecholamines induced slow action potentials accompanied by contractions. Elevation of the concentration of these agents produced increases in + Vmax, dTdt, and cyclic AMP in a dose-dependent fashion; a close correlation was obtained between the cyclic AMP level, + Vmax and dTdt. These results support the hypothesis that the increases in + Vmax of the slow action potentials and in contraction are explained by increase in the number of available slow channels mediated by intracellular cyclic AMP levels, and the resulting increase in the Ca2+ influx.  相似文献   
993.
Peri-procedural myocardial injury: 2005 update.   总被引:14,自引:0,他引:14  
During the past three decades, percutaneous coronary intervention has become one of the cardinal treatment strategies for stenotic coronary artery disease. Technical advances, including the introduction of new devices such as stents, have expanded the interventional capabilities of balloon angioplasty. At the same time, there has been a decline in the rate of major adverse cardiac events, including Q-wave acute myocardial infarction, emergency coronary artery bypass grafting, and cardiac death. Despite these advances, the incidence of post-procedural cardiac marker elevation has not substantially decreased since the first serial assessment 20 years ago. As of now, these post-procedural cardiac marker elevations are considered to represent peri-procedural myocardial injury (PMI) with worse long-term outcome potential. Recent progress has been made for the identification of two main PMI patterns, one near the intervention site (proximal type, PMI type I) and one in the distal perfusion territory of the treated coronary artery (distal type, PMI type II) as well as for preventive strategies. Integrating these new developments into the wealth of clinical information on this topic, this review aims at giving a current perspective on the entity of PMI.  相似文献   
994.
Introduction  Venoplasty allows the addition or replacement of leads despite subtotal or total subclavian occlusion. Methods  The threshold of the LV pacing lead implanted for biventricular pacing over a period of 18 months increased to greater than 5 V. A pre implant venogram revealed total subclavian occlusion. Venous access was maintained by extraction of the 4 F LV lead over a wire. Subsequently the sheath would not advance despite 6mm balloon inflation to 30 atm with no residual waist. A wire was placed beside the balloon and the balloon was reinflated. Results  The subclavian obstruction was eliminated without damage to the existing leads. Conclusion  The obstruction formed by the fibrous track around an extracted lead may persist despite what appears to be successful balloon dilation. Inflation with a wire beside the balloon increases the effect eliminating the resistant obstruction without damaging the leads. Acknowledgements of Sources of Financial Support:Dr. Worley receives compensation in various forms from Medtronic, Pressure Products, Guidant, and St Jude Medical. Dr. Gohn receives compensation in various forms from Medtronic. No financial support was provided for the creation of this case report  相似文献   
995.
目的:观察卡维地洛(Carvedilol)治疗慢性心力衰竭(CHF)的临床疗效。方法:将80例NYHA心功能Ⅱ~Ⅳ级CHF患者随机分为两组:Carvedilol组40例,采用常规治疗(ACEI、利尿剂、血管扩张剂、有或无洋地黄)+Carvedilol;Betaloc组40例,常规治疗+Betaloc。随访1~2年,观察两组治疗前后血流动力学、左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)、左室射血分数(LVEF)、6min步行距离(6-MWD)及心功能变化。结果:两组治疗后心率(HR)、收缩压(SBP)、心肌耗氧量(HR×SBP)、LVEDD、LVESD、LVEF、左室短轴缩短分数(LVFS)、NYHA心功能分级均较治疗前显著改善(P<0.01),而Carvedilol组在血流动力学及心功能改善上较Betaloc组更明显(P<0.05);但治疗后组间HR降低无显著差异(P>0.05)。两组治疗后6-MWD也均较治疗前显著增加(P<0.01),尤其Carvedilol组(P<0.05)。Carvedilol组无不良反应出现。结论:联用Carvedilol治疗CHF安全有效。  相似文献   
996.
997.
目的探讨血管紧张素(1~7)[Ang(1~7)]对血管加压素(AVP)诱导心脏成纤维细胞(CFs)增殖的影响及其与钙调神经磷酸酶(CaN)的关系。方法分离培养SD仔鼠CFs,四氮唑盐(MTT)比色法检测细胞增殖,采用流式细胞分析仪技术测定细胞周期,发色底物法测定细胞内CaN的活性。结果(1)10-7mol/LAVP干预24h后,CFs的MTT吸光度值(0.24±0.01)较对照组(0.14±0.01)明显增高(P<0.01);给予10-9~10-6mol/LAng(1~7)和AVP共同干预后,CFs的吸光度值呈递减趋势,分别为0.22±0.01、0.21±0.01、0.18±0.01和0.16±0.01,均较AVP组降低,差异有统计学意义(P<0.01)。(2)AVP刺激后,CFs的S期百分率(14.00±0.94)和增殖指数(23.4±1.8)较对照组(分别为5.4±0.7和10.8±2.4)明显增高(P<0.01);10-7mol/LAng(1~7)和AVP共同作用后S期百分率(8.5±0.7)和增殖指数(16.2±2.0)较AVP组降低,差异有统计学意义(P<0.01)。(3)AVP组CFs内CaN活性(0.27±0.02kU/mg)较对照组(0.12±0.01)kU/mg明显增加(P<0.01),给予10-9~10-6mol/LAng(1~7)和AVP共同干预后,CaN活性分别为0.25±0.01、0.20±0.02、0.17±0.01和0.15±0.02(kU/mg),均较AVP组降低,差异有统计学意义(P<0.01)。结论Ang(1~7)能抑制AVP诱导CFs增殖,CaN活性降低可能是其分子生物学机制之一。  相似文献   
998.

Background/Aim:

The aim of this study was to investigate the effects of celiac disease on cardiac functions using tissue Doppler echocardiography (TDE).

Patients and Methods:

The study included 30 patients with celiac disease (CD) and 30 healthy volunteers. Echocardiographic examinations were assessed by conventional echocardiography and tissue Doppler imaging. The peak systolic velocity (S''m), early diastolic myocardial peak velocity (E''m), late diastolic myocardial peak velocity (A''m), E''m/A''m ratio, myocardial precontraction time (PCT''m), myocardial contraction time (CT''m), and myocardial isovolumetric relaxation time (IVRT''m), E to E''m ratio were measured.

Results:

In pulsed wave Doppler echocardiography, mitral late diastolic flow (A) velocity and E to E''m ratio were significantly higher (P = 0.02 and P = 0,017), E/A ratio was significantly lower (P = 0.008) and IVRT was significantly prolonged (P = 0.014) in patients with CD. In TDE, S''m, E''m, and E''m/A''m ratio were significantly lower, IVRT''m was longer (P = 0.009) from septal mitral annulus and S''m, E''m, E''m/A''m ratio were significantly lower, PCT''m, PCT/ET ratio, IVRT''m were longer, and MPI was higher from lateral mitral annulus in celiac group than controls.

Conclusion:

Our study confirms that patients with CD have impaired diastolic function. More importantly, we also demonstrated an impairment of myocardial systolic function in patients with CD by TDE. We recommend using TDE in addition to conventional echocardiography parameters for the cardiovascular risk assessment of patients with CD.  相似文献   
999.
目的 探讨血清肌酸激酶同工酶 (CK- MB)、心肌肌钙蛋白 I(c Tn I)、肌红蛋白 (Mb)检测 ,对射频消融术 (RF-CA)所致心肌损伤的诊断价值。方法 选择 30例室上性心动过速患者 ,分别于 RFCA前、电生理检查后、术后即刻、术后 1d、2 d采外周静脉血 ,采用美国德普公司自动免疫化学发光分析仪分别测定血清 CK- MB、 c Tn I、Mb。结果  CK- MB术后 1d较术前增高 (P<0 .0 1) ;c Tn I与术前相比术后 1d、2 d明显增高 (P<0 .0 5 ) ;与术前相比术后即刻 Mb明显增高 (P<0 .0 1)。结论  RFCA所造成心肌损伤属微小心肌损伤 ,可使血清心肌损害标志物有不同程度的升高 ,CK- MB、c Tn I、Mb可用于 RFCA对心肌损伤的监测。  相似文献   
1000.
BACKGROUND: Diabetes mellitus is an independent risk factor for increased morbidity and mortality in heart failure (HF) patients. AIMS: To compare functional and structural improvement, as well as long-term outcome, between diabetic and non-diabetic HF patients treated with cardiac resynchronization therapy (CRT). METHODS: We compared response to CRT in 141 diabetic and 214 non-diabetic consecutive patients. Major events were; death from any cause, urgent heart transplantation and implantation of a left ventricular (LV) assist device. Frequencies of hospitalisation and defibrillator (CRT-D) discharges were also analyzed. RESULTS: CRT was able to significantly improve functional capacity, ventricular geometry and neurohumoral imbalance in both diabetic and non-diabetic patients over a median follow-up time of 34 months. Overall event-free survival was similar in diabetic and non-diabetic patients (HR 1.23, p=0.363), as was survival free from CRT-D interventions (HR 1.72; p=0.115) and hospitalisations (HR 1.12; p=0.500). On multivariable analysis, NYHA class IV (p=0.002), low LV ejection fraction (p=0.002), absence of beta-blocker therapy (p<0.001), impaired renal function (p=0.003), presence of an epicardial lead (p=0.025), but not diabetes (p=0.821) were associated with a poor outcome after CRT. CONCLUSIONS: Diabetic HF patients treated with CRT had a very favourable functional and survival outcome, which was comparable to non-diabetic patients.  相似文献   
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