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91.
Brugada syndrome (BrS) is a primary electrical disease associated with increased risk of sudden cardiac death due to polymorphic ventricular arrhythmias. The prognosis, risk stratification, and management of asymptomatic individuals remain the most controversial issues in BrS. Furthermore, the decision to manage asymptomatic patients with an implantable cardioverter‐defibrillator should be made after weighing the potential individual risk of future arrhythmic events against the risk of complications associated with the implant and follow‐up of patients living with such devices, and the accompanying impairment of the quality of life. Several clinical, electrocardiographic, and electrophysiological markers have been proposed for risk stratification of subjects with BrS phenotype, but the majority have not yet been tested in a prospective manner in asymptomatic individuals. Recent data suggest that current risk factors are insufficient and cannot accurately predict sudden cardiac death events in this setting. This systematic review aims to discuss contemporary data regarding prognosis, risk stratification, and management of asymptomatic individuals with diagnosis of Brugada electrocardiogram pattern and to delineate the therapeutic approach in such cases.  相似文献   
92.
Secondary amyloidosis (SA) affects cardiac texture and function by interstitial fibrosis. Doppler tissue imaging (DTI) may quantify heart function through the assessment of myocardial velocities. Echocardiographic findings of early cardiac amyloidosis (CA) without heart failure (HF) caused by SA were determined both by standard methods and DTI. It was then determined whether DTI is superior to conventional echocardiography in documenting early CA due to SA. Twenty-five patients with SA who had CA without HF (group 1) were compared with 25 healthy control subjects (group 2). After standard echocardiography, systolic (s), early (e) and late diastolic (a) velocities of interventricular septum, anterolateral, and anterior and inferior walls were measured from mitral annulus by DTI. The averages were called (smean), (emean), and (amean), respectively. Fractional shortening (FS) and ejection fraction (EF) values of groups 1 and 2 were similar. Standard Doppler echocardiographic values were not typical for a specific diastolic abnormality. The (smean) and (emean) for group 1 were lower but (amean) was higher compared with group 2 (all P < .05). The group 1 (emean/amean) was lower (P < .0001) and (E/emean) was higher (P=.003) than in group 2 (both P < .05). (E/emean) and (E/elateral wall) ratios were positively correlated (r=0.74, P < .05). In patients with early CA due to SA without HF, by DTI, (smean) and (emean) velocities decrease and (amean) velocity increases. These may be markers of subclinical CA of SA when standard echocardiography is not informative. (E/emean) ratio may be an alternative index to (E/elateral wall).  相似文献   
93.
BACKGROUND AND METHOD: Although direct coronary stenting does not improve angiographic outcome, it makes sense by reducing procedure times, radiation exposure and costs. Other potential advantages of direct stenting may be a reduction of myocardial ischemia time, which could be clinically relevant in high-risk patients. With the introduction of drug-eluting stents, however, concern arose that direct stenting would possibly damage the polymer coating and change or diminish the efficacy of the programmed drug release. Also, concerns about safety by preventing optimal apposition of single stent struts developed. It is the purpose of this paper to retrospectively analyze the data from the TAXUS-II Trial (536 patients) regarding patients with and without direct stenting. While predilatation was recommended per protocol, direct stenting was not forbidden: thus, direct stenting was performed in 49 patients (TAXUS n = 23, control n = 26). RESULTS: In the TAXUS groups, there was no significant difference regarding major adverse cardiac events (MACE; 7.5% vs. 4.3%), angiographic restenosis in the analysis segment (4.8% vs. 4.3%), late loss (0.28 +/- 0.36 vs. 0.33 +/- 0.30 mm) or intravascular ultrasound-(IVUS-)measured volume obstruction (7.95 +/- 9.84% vs. 5.61 +/- 7.91%) at six months between the predilated and directly stented patients. The same was true for the patients receiving the control stent. Compared with the directly stented control group, the statistically significant positive effects of TAXUS direct stenting were maintained, regarding angiographic restenosis in the analysis segment (4.3% vs. 30.8%), late loss (0.33 +/- 0.30 vs. 0.80 +/- 0.62 mm) or IVUS-measured volume obstruction (5.61 +/- 7.91% vs. 22.50 +/- 21.62%) at six months. MACE was reduced from 19.2% to 4.3%; due to the small number of patients this trend did not reach statistical significance. After predilatation, all parameters were significantly improved by the TAXUS stent. CONCLUSION: Comparison of patients receiving TAXUS stents with or without predilatation revealed no differences in clinical, angiographic or IVUS parameters at six months. This suggests that direct stenting with the polymer-based paclitaxel-eluting TAXUS stent is feasible, safe and equally effective. Randomized trials comparing stenting after predilatation versus direct stenting with drug-eluting stents are warranted.  相似文献   
94.
Objective: The objective of this study was to evaluate the efficacy of hemostasis with patency in avoiding radial artery occlusion after transradial catheterization. Background: Radial artery occlusion is an infrequent but discouraging complication of transradial access. It is related to factors such as sheath to artery ratio and is less common in patients receiving heparin. Despite being clinically silent in most cases, it limits future transradial access. Patients and Methods: Four hundred thirty‐six consecutive patients undergoing transradial catheterization were prospectively enrolled in the study. Two hundred nineteen patients were randomized to group I, and underwent conventional pressure application for hemostasis. Two hundred seventeen patients were randomized to group II and underwent pressure application confirming radial artery patency using Barbeau's test. Radial artery patency was studied at 24 hr and 30 days using Barbeau's test. Results: Thirty‐eight patients had evidence of radial artery occlusion at 24 hr. Twenty patients had persistent evidence of radial artery occlusion at 1 month. Group II, with documented patency during hemostatic compression, had a statistically and clinically lower incidence of radial artery occlusion (59% decrease at 24 hr and 75% decrease at 30 days, P < 0.05), compared with patients in group I. Low body weight patients were at significantly higher risk of radial artery occlusion. No procedural variables were found to be associated with radial artery occlusion. Conclusion: Patent hemostasis is highly effective in reducing radial artery occlusion after radial access and guided compression should be performed to maintain radial artery patency at the time of hemostasis, to prevent future radial artery occlusion. © 2008 Wiley‐Liss, Inc.  相似文献   
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97.
  • Severe mitral regurgitation (MR) may lead to worsening renal function due to a decrease in stroke volume, increase in systemic vascular resistance, and venous pooling.
  • Percutaneous treatment with MitraClip seems to improve renal function in certain patient groups.
  • Larger studies are needed to prove that MitraClip is the preferred strategy in patients with severe MR and chronic kidney disease
  相似文献   
98.
  • The MATRIX Trial proved that radial was superior to femoral in ACS patients due to reduction in complications with equal effectiveness.
  • This large study suggests that the radial approach can be equally successful compared to the femoral approach in CTOs.
  • Since so few radial CTO procedures were included, one wonders whether CTO operators with MATRIX‐like radial experience could have less complications than the femoral approach in these procedures.
  相似文献   
99.
Background: Few data are available about postdilatation (PD) for the treatment of significant paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation of the Edwards valve. Methods and Results : A total of 470 patients, aged 83.4 ± 6.4 yrs, with logistic European System for Cardiac Operative Risk Evaluation 21.9 ± 12.3, undergoing transcatheter aortic valve implantation with the Edwards valve were evaluated. PD was performed using the balloon delivery system when significant paravalvular AR was identified. The diameter of the valve was measured from cine acquisition at three different levels. PD was performed in 49 (10.4%) patients with grade 2, 3, or 4 AR as 42.1%, 55.3%, and 2.6%, respectively. After PD, a reduction of at least 1 degree of AR was achieved in 81.5% of cases. Residual AR grades 2, 3, and 4 were observed in 36.8%, 10.5%, and 0%, respectively. A significant increase in the prosthesis diameter was observed at the three valve levels (absolute Δ 3.5%–5.4%, P.< 0.01). For the 23 mm valve, mid level of valve increased from 23.0 ± 0.4 to 24.1 ± 0.5 mm (P < 0.01) and for the 26 mm, from 25.2 ± 0.9 to 26.6 ± 0.9 mm (P < 0.01). Occurrence of annulus rupture (4.1% vs. 1.7%, P = 0.24), cerebrovascular accidents (2.0% vs. 2.1%, P = 0.72), need for new pacemaker (8.2% vs. 5.5%, P = 0.31), and 30‐day composite endpoint (24.5% vs. 20.2%, P = 0.48) were not significantly different between PD and non‐PD groups. Conclusions : PD for the treatment of significant paravalvular leak proved to be a feasible treatment allowing a significant increase in valve size and decrease in PVL without increase in stroke rates. This promising approach needs further confirmation. © 2014 Wiley Periodicals, Inc.  相似文献   
100.
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