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101.
102.

Background

Atherosclerotic plaque characteristics may affect downstream myocardial perfusion, as well as coronary lesion severity.

Objectives

This study sought to evaluate the association between quantitative plaque burden and plaque morphology obtained using coronary computed tomography angiography (CTA) and quantitative myocardial perfusion obtained using [15O]H2O positron emission tomography (PET), as well as fractional flow reserve (FFR) derived invasively.

Methods

Two hundred eight patients (63% men; age 58 ± 8.7 years) with suspected coronary artery disease were prospectively included. All patients underwent 256-slice coronary CTA, [15O]H2O PET, and invasive FFR measurements. Coronary CTA-derived plaque burden and morphology were assessed using commercially available software and compared with PET perfusion and FFR.

Results

Atherosclerotic plaques were present in 179 patients (86%) and 415 of 610 (68%) evaluable coronary arteries. On a per-vessel basis, traditional coronary plaque burden indexes, such as plaque length and volume, minimal lumen area, and stenosis percentage, were significantly associated with impaired hyperemic myocardial blood flow (MBF) and FFR. In addition, morphological features, such as partially calcified plaques, positive remodeling (PR), and low attenuation plaque, displayed a negative impact on hyperemic MBF and FFR. Multivariable analysis revealed that the morphological feature of PR was independently related to impaired hyperemic MBF as well as an unfavorable FFR (p = 0.004 and p = 0.007, respectively), next to stenosis percentage (p = 0.001 and p < 0.001, respectively) and noncalcified plaque volume (p < 0.001 and p = 0.010, respectively).

Conclusions

PR and noncalcified plaque volume are associated with detrimental downstream hyperemic myocardial perfusion and FFR, independent of lesion severity.  相似文献   
103.

Background

There is limited information on the incidence and prognostic impact of new-onset atrial fibrillation (NOAF) following percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for left main coronary artery disease (LMCAD).

Objectives

This study sought to determine the incidence of NOAF following PCI and CABG for LMCAD and its effect on 3-year cardiovascular outcomes.

Methods

In the EXCEL (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial, 1,905 patients with LMCAD and low or intermediate SYNTAX scores were randomized to PCI with everolimus-eluting stents versus CABG. Outcomes were analyzed according to the development of NOAF during the initial hospitalization following revascularization.

Results

Among 1,812 patients without atrial fibrillation on presentation, NOAF developed at a mean of 2.7 ± 2.5 days after revascularization in 162 patients (8.9%), including 161 of 893 (18.0%) CABG-treated patients and 1 of 919 (0.1%) PCI-treated patients (p < 0.0001). Older age, greater body mass index, and reduced left ventricular ejection fraction were independent predictors of NOAF in patients undergoing CABG. Patients with versus without NOAF had a significantly longer duration of hospitalization, were more likely to be discharged on anticoagulant therapy, and had an increased 30-day rate of Thrombolysis In Myocardial Infarction major or minor bleeding (14.2% vs. 5.5%; p < 0.0001). By multivariable analysis, NOAF after CABG was an independent predictor of 3-year stroke (6.6% vs. 2.4%; adjusted hazard ratio [HR]: 4.19; 95% confidence interval [CI]: 1.74 to 10.11; p = 0.001), death (11.4% vs. 4.3%; adjusted HR: 3.02; 95% CI: 1.60 to 5.70; p = 0.0006), and the primary composite endpoint of death, MI, or stroke (22.6% vs. 12.8%; adjusted HR: 2.13; 95% CI: 1.39 to 3.25; p = 0.0004).

Conclusions

In patients with LMCAD undergoing revascularization in the EXCEL trial, NOAF was common after CABG but extremely rare after PCI. The development of NOAF was strongly associated with subsequent death and stroke in CABG-treated patients. Further studies are warranted to determine whether prophylactic strategies to prevent or treat atrial fibrillation may improve prognosis in patients with LMCAD who are undergoing CABG. (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776)  相似文献   
104.
Renal impairment is an important predictor of mortality after percutaneous coronary intervention and may increase the restenosis rate. However, the relation between restenosis and the risk of death in patients who have renal impairment remains unclear. We evaluated the incidences of repeat revascularization and mortality in patients who had renal impairment and those who did not and who received sirolimus-eluting stents or bare stents. A total of 1,080 consecutive patients treated for 1 year had available data to calculate baseline creatinine clearance. Patients received bare stents (first 6 months, n = 543) or sirolimus-eluting stents (last 6 months, n = 537) and were grouped according to the presence or absence of renal impairment (creatinine clearance <60 ml/min). Patients who had renal impairment had a higher mortality rate at 1 year (7.6% vs 2.5%, hazard ratio 3.14, 95% confidence interval 1.68 to 5.88, p <0.01), with no differences in mortality between patients who received bare stents and those who received sirolimus-eluting stents (hazard ratio 0.91, 95% confidence interval 0.49 to 1.68, p = 0.8). The incidence of target vessel revascularization decreased significantly in patients who were treated with sirolimus-eluting stents and did not have renal impairment (hazard ratio 0.59, 95% confidence interval 0.39 to 0.90, p = 0.01) and in those who had decreased renal function (hazard ratio 0.37, 95% confidence interval 0.15 to 0.90, p = 0.03). Thus, sirolimus-eluting stents compared with conventional stents decreased clinical restenosis in patients who had renal impairment. However, this benefit was not paralleled by a decrease in the risk of death in this population. It seems unlikely that restenosis could be a contributing factor that influenced the increased mortality of patients who had impaired renal function.  相似文献   
105.
Future therapy options for multiple myeloma may be directed at asymptomatic disease, as only symptomatic myeloma is treated currently. Additional genetic information from gene array analysis will mean that the identification of cases with poor prognosis will become more sophisticated. New markers are being discovered constantly, and these continuously change the picture regarding prognostic factors. More intensive treatment options increase the depth of remissions, thereby improving outcomes. In pilot studies, cyclophosphamide, thalidomide and dexamethasone (CTD) was a highly effective, well-tolerated regimen for patients refractory to initial therapy with VAD or with relapsed disease. It is being further evaluated as induction therapy in the current MRC Myeloma IX trial. Also under investigation is a small molecule derivative of thalidomide, CC-4047 (Actimid). It has between 1,000 and 10,000 times more potent antitumour necrosis factor alpha activity, with an additional immunomodulatory effect. It has been shown to be between 50 and 2,000 times more potent in the stimulation of T-cell proliferation and 50-100 times more potent in augmenting interleukin-2 and interferon-gamma production. With many possible approaches to study and work through, future strategies will revolve around exploration of the effectiveness of combinations that incorporate new agents in various disease and treatment settings. The use of genetic profiles to further delineate groups for different treatment approaches should enable the introduction of patient-specific treatment programmes in the future.  相似文献   
106.

Objectives

The authors sought to investigate the impact of diabetes mellitus (DM) on outcomes following contemporary drug-eluting stent (DES) implantation in the BIONICS (BioNIR Ridaforolimus Eluting Coronary Stent System in Coronary Stenosis) trial.

Background

Patients with DM are at increased risk for adverse events following percutaneous coronary intervention (PCI).

Methods

A prospective, multicenter, 1:1 randomized trial was conducted to evaluate in a noninferiority design the safety and efficacy of ridaforolimus-eluting stents versus zotarolimus-eluting stents among 1,919 patients undergoing PCI. Randomization was stratified to the presence of medically treated DM, and a pre-specified analysis compared outcomes according to the presence or absence of DM up to 2 years.

Results

The overall prevalence of DM was 29.1% (559 of 1,919). DM patients had higher body mass index, greater prevalence of hyperlipidemia and hypertension, and smaller reference vessel diameter. One-year target lesion failure (cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization) was significantly higher among diabetic patients (7.8% vs. 4.2%; p = 0.002), mainly due to higher target lesion revascularization (4.5% vs. 2.0%; p = 0.002). Rates of cardiac death, myocardial infarction, and stent thrombosis did not statistically vary. Among 158 patients undergoing 13-month angiographic follow-up, restenosis rates were 3 times higher in diabetic patients compared with nondiabetic patients (15.2% vs. 4.7%; p = 0.01). Clinical and angiographic outcomes were similar between ridaforolimus-eluting stent– and zotarolimus-eluting stent–treated patients.

Conclusions

Despite advances in interventional therapies, and the implementation of new-generation DES, diabetic patients still have worse angiographic and clinical outcomes compared with nondiabetic patients undergoing PCI.  相似文献   
107.
There is little data available to guide amoxicillin-clavulanic acid dosing in critically ill children. The primary objective of this study was to investigate the pharmacokinetics of both compounds in this pediatric subpopulation. Patients admitted to the pediatric intensive care unit (ICU) in whom intravenous amoxicillin-clavulanic acid was indicated (25 to 35 mg/kg of body weight every 6 h) were enrolled. Population pharmacokinetic analysis was conducted, and the clinical outcome was documented. A total of 325 and 151 blood samples were collected from 50 patients (median age, 2.58 years; age range, 1 month to 15 years) treated with amoxicillin and clavulanic acid, respectively. A three-compartment model for amoxicillin and a two-compartment model for clavulanic acid best described the data, in which allometric weight scaling and maturation functions were added a priori to scale for size and age. In addition, plasma cystatin C and concomitant treatment with vasopressors were identified to have a significant influence on amoxicillin clearance. The typical population values of clearance for amoxicillin and clavulanic acid were 17.97 liters/h/70 kg and 12.20 liters/h/70 kg, respectively. In 32% of the treated patients, amoxicillin-clavulanic acid therapy was stopped prematurely due to clinical failure, and the patient was switched to broader-spectrum antibiotic treatment. Monte Carlo simulations demonstrated that four-hourly dosing of 25 mg/kg was required to achieve the therapeutic target for both amoxicillin and clavulanic acid. For patients with augmented renal function, a 1-h infusion was preferable to bolus dosing. Current published dosing regimens result in subtherapeutic concentrations in the early period of sepsis due to augmented renal clearance, which risks clinical failure in critically ill children, and therefore need to be updated. (This study has been registered at Clinicaltrials.gov as an observational study [NCT02456974].)  相似文献   
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