Complete Revascularization Versus Culprit-Lesion-Only PCI in STEMI Patients With Diabetes and Multivessel Coronary Artery Disease: Results From the COMPLETE Trial

BACKGROUND

In the COMPLETE trial (Complete Versus Culprit-Only Revascularization to Treat Multivessel Disease After Early PCI for STEMI), a strategy of complete revascularization reduced the risk of major cardiovascular events compared with culprit-lesion-only percutaneous coronary intervention in patients presenting with ST-segment-elevation myocardial infarction (STEMI) and multivessel coronary artery disease. Patients with diabetes have a worse prognosis following STEMI. We evaluated the consistency of the effects of complete revascularization in patients with and without diabetes.

METHODS

The COMPLETE trial randomized a strategy of complete revascularization, consisting of angiography-guided percutaneous coronary intervention of all suitable nonculprit lesions, versus a strategy of culprit-lesion-only percutaneous coronary intervention (guideline-directed medical therapy alone). In prespecified analyses, treatment effects were determined in patients with and without diabetes on the first coprimary outcome of cardiovascular death or new myocardial infarction and the second coprimary outcome of cardiovascular death, new myocardial infarction, or ischemia-driven revascularization. Interaction P values were calculated to evaluate whether there was a differential treatment effect in patients with and without diabetes.

RESULTS

Of the 4041 patients enrolled in the COMPLETE trial, 787 patients (19.5%) had diabetes. The median HbA1c (glycated hemoglobin) was 7.7% in the diabetes group and 5.7% in the nondiabetes group. Complete revascularization consistently reduced the first coprimary outcome in patients with diabetes (hazard ratio, 0.87 [95% CI, 0.59-1.29]) and without diabetes (hazard ratio, 0.70 [95% CI, 0.55-0.90]), with no evidence of a differential treatment effect (interaction P=0.36). Similarly, for the second coprimary outcome, no differential treatment effect (interaction P=0.27) of complete revascularization was found in patients with diabetes (hazard ratio, 0.61 [95% CI, 0.43-0.87]) and without diabetes (hazard ratio, 0.48 [95% CI, 0.39-0.60]).

CONCLUSIONS

Among patients presenting with STEMI and multivessel disease, the benefit of complete revascularization over a culprit-lesion-only percutaneous coronary intervention strategy was consistent regardless of the presence or absence of diabetes.

Contemporary use of guideline-based higher potency P2Y12 receptor inhibitor therapy in patients with moderate-to-high risk non-ST-segment elevation myocardial infarction: Results from the Canadian ACS reflective II cross-sectional study

Background

After myocardial infarction, guidelines recommend higher‐potency P2Y12 receptor inhibitors, namely ticagrelor and prasugrel, over clopidogrel.

Hypothesis

We aimed to determine the contemporary use of higher‐potency antiplatelet therapy in Canadian patients with non‐ST‐elevation myocardial infarction (NSTEMI).

Methods

A total of 684 moderate‐to‐high risk NSTEMI patients were enrolled in the prospective Canadian ACS Reflective II registry at 12 Canadian hospitals and three clinics in five provinces between July 2016 and May 2018. Multivariable logistic regression modeling was performed to assess factors independently associated with higher‐potency P2Y12 receptor inhibitor use at discharge.

Results

At hospital discharge, 78.3% of patients were treated with a P2Y12 receptor inhibitor. Among patients discharged on a P2Y12 receptor inhibitor, use of higher‐potency P2Y12 receptor inhibitor was 61.4%. After adjustment, treatment in‐hospital with PCI (OR 4.48, 95%CI 3.34–6.03, p < .0001) was most strongly associated with higher use of higher‐potency P2Y12 receptor inhibitor, while oral anticoagulant use at discharge (OR 0.03, 95%CI 0.01–0.12, p < .0001), and atrial fibrillation (OR 0.40, 95%CI 0.17–0.98, p = .046) were most strongly associated with lower use of higher‐potency P2Y12 receptor inhibitor. Use of higher‐potency P2Y12 receptor inhibitor varied across provinces (range, 21.6%–78.9%).

Discussion

In contemporary Canadian practice, approximately 60% of moderate‐to‐high risk NSTEMI patients discharged on a P2Y12 receptor inhibitor are treated with a higher‐potency P2Y12 receptor inhibitor. In addition to factors that increase risk of bleeding, interprovincial differences in practice patterns were associated with use of higher‐potency P2Y12 receptor inhibitor at discharge. Opportunities remain for further optimization of evidence‐based, guideline‐recommended antiplatelet therapy use.

Nonculprit Lesion Plaque Morphology in Patients With ST-Segment–Elevation Myocardial Infarction

Background:

Complete revascularization with routine percutaneous coronary intervention of nonculprit lesions after primary percutaneous coronary intervention improves outcomes in ST-segment–elevation myocardial infarction. Whether this benefit is associated with nonculprit lesion vulnerability is unknown.

Methods:

In a prospective substudy of the COMPLETEs trial (Complete vs Culprit-Only Revascularization to Treat Multi-Vessel Disease After Early PCI for STEMI), we performed optical coherence tomography of at least 2 coronary arteries before nonculprit lesion percutaneous coronary intervention in 93 patients with ST-segment–elevation myocardial infarction and multivessel disease; and the ST-segment–elevation myocardial infarction culprit vessel if there was unstented segment amenable to imaging. Nonculprit lesions were categorized as obstructive (≥70% stenosis by visual angiographic assessment) or nonobstructive, and as thin-cap fibroatheroma (TCFA) or non-TCFA by optical coherence tomography criteria. TCFA was defined as a lesion with mean fibrous cap thickness <65 μm overlying a lipid arc >90°.

Results:

On a patient level, at least one obstructive TCFA was observed in 44/93 (47%) of patients. On a lesion level, there were 58 TCFAs among 150 obstructive nonculprit lesions compared with 74 TCFAs among 275 nonculprit lesions (adjusted TCFA prevalence: 35.4% versus 23.2%, P =0.022). Compared with obstructive non-TCFAs, obstructive TCFAs had similar lesion length (23.1 versus 20.8 mm, P =0.16) but higher lipid quadrants (55.2 versus 19.2, P <0.001), greater mean lipid arc (203.8° versus 84.5°, P <0.001), and more macrophages (97.1% versus 54.4%, P <0.001) and cholesterol crystals (85.8% versus 44.3%, P <0.001). For nonobstructive lesions, TCFA lesions had similar lesion length (16.7 versus 14.6 mm, P =0.11), but more lipid quadrants (36.4 versus 13.5, P <0.001), and greater mean lipid arc (191.8° versus 84.2°, P <0.001) compared with non-TCFA.

Conclusions:

Among patients who underwent optical coherence tomography imaging in the COMPLETE trial, nearly 50% had at least one obstructive nonculprit lesion containing complex vulnerable plaque. Obstructive lesions more commonly harbored vulnerable plaque morphology than nonobstructive lesions. This may help explain the benefit of routine percutaneous coronary intervention of obstructive nonculprit lesions in patients with ST-segment–elevation myocardial infarction and multivessel disease.

Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01740479s.

Myocardial blush and microvascular reperfusion following manual thrombectomy during percutaneous coronary intervention for ST elevation myocardial infarction: insights from the TOTAL trial

AIMS

Thrombectomy during primary percutaneous coronary intervention (PPCI) for ST elevation myocardial infarction (STEMI) has been thought to be an effective therapy to prevent distal embolization and improve microvascular perfusion. The TOTAL trial (N = 10 732), a randomized trial of routine manual thrombectomy vs. PCI alone in STEMI, showed no difference in the primary efficacy outcome. This angiographic sub-study was performed to determine if thrombectomy improved microvascular perfusion as measured by myocardial blush grade (MBG).

METHODS AND RESULTS

Of the 10 732 patients randomized, 1610 randomly selected angiograms were analysable by the angiographic core laboratory. Primary outcomes included MBG and post-PCI thrombolysis in myocardial infarction (TIMI) flow grade. Secondary outcomes included distal embolization, PPCI complications, and each component of the complications. The primary end point of final myocardial blush (221 [28%] 0/1 for thrombectomy vs. 246 {30%} 0/1 for PCI alone group, P = 0.38) and TIMI flow (712 [90%] TIMI 3 for thrombectomy vs. 733 [89.5%] TIMI 3 for PCI alone arm, P = 0.73) was similar in the two groups. Thrombectomy was associated with a significantly reduced incidence of distal embolization compared with PCI alone (56 [7.1%] vs. 87 [10.7%], P = 0.01). In multivariable analysis, distal embolization was an independent predictor of mortality (HR 3.00, 95% CI 1.19-7.58) while MBG was not (HR 2.73, 95% CI 0.94-5.3).

CONCLUSIONS

Routine thrombectomy during PPCI did not result in improved MBG or post-PCI TIMI flow grade but did reduce distal embolization compared with PCI alone. Distal embolization and not blush grade is independently associated with mortality.

Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial

BACKGROUND

Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice.

METHODS

The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10,732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044.

FINDINGS

Between Aug 5, 2010, and July 25, 2014, 10,732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not undergo PCI in each group (337 in the PCI and thrombectomy group and 331 in the PCI alone group), the final study population comprised 10,064 patients (5035 thrombectomy and 5029 PCI alone). The primary outcome at 1 year occurred in 395 (8%) of 5035 patients in the thrombectomy group compared with 394 (8%) of 5029 in the PCI alone group (hazard ratio [HR] 1·00 [95% CI 0·87-1·15], p=0·99). Cardiovascular death within 1 year occurred in 179 (4%) of the thrombectomy group and in 192 (4%) of 5029 in the PCI alone group (HR 0·93 [95% CI 0·76-1·14], p=0·48). The key safety outcome, stroke within 1 year, occurred in 60 patients (1·2%) in the thrombectomy group compared with 36 (0·7%) in the PCI alone group (HR 1·66 [95% CI 1·10-2·51], p=0·015).

INTERPRETATION

Routine thrombus aspiration during PCI for STEMI did not reduce longer-term clinical outcomes and might be associated with an increase in stroke. As a result, thrombus aspiration can no longer be recommended as a routine strategy in STEMI.

FUNDING

Canadian Institutes of Health Research, Canadian Network and Centre for Trials Internationally, and Medtronic Inc.

Stroke in the TOTAL trial: a randomized trial of routine thrombectomy vs. percutaneous coronary intervention alone in ST elevation myocardial infarction

AIMS

TOTAL (N = 10 732), a randomized trial of routine manual thrombectomy vs. percutaneous coronary intervention alone in ST elevation myocardial infarction, showed no difference in the primary efficacy outcome but a significant increase in stroke. We sought to understand these findings.

METHODS AND RESULTS

A detailed analysis of stroke timing, stroke severity, and stroke subtype was performed. Strokes were adjudicated by neurologists blinded to treatment assignment. Stroke within 30 days, the primary safety outcome, was increased [33 (0.7%) vs. 16 (0.3%), hazard ratio (HR) 2.06; 95% confidence interval (CI) 1.13-3.75]. The difference in stroke was apparent within 48 h [15 (0.3%) vs. 5 (0.1%), HR 3.00; 95% CI 1.09-8.25]. There was an increase in strokes within 180 days with minor or no disability (Rankin 0-2) [18 (0.4%) vs. 13 (0.3%) HR 1.38; 95% CI 0.68-2.82] and in strokes with major disability or fatal (Rankin 3-6) [35 (0.7%) vs. 13 (0.3%), HR 2.69; 95% CI 1.42-5.08]. Most of the absolute difference was due to an increase in ischaemic strokes within 180 days [37 (0.7%) vs. 21 (0.4%), HR 1.71; 95% CI 1.03-3.00], but there was also an increase in haemorrhagic strokes [10 (0.2%) vs. 2 (0.04%), HR 4.98; 95% CI 1.09-22.7]. Patients that had a stroke had a mortality of 30.8% within 180 days vs. 3.4% without a stroke (P < 0.001). A meta-analysis of randomized trials (N = 21 173) showed an increase in risk of stroke (odds ratio 1.59; 95% CI 1.11-2.27) but a trend towards reduction in mortality odds ratio (odds ratio 0.87; 95% CI 0.76-1.00).

CONCLUSION

Thrombectomy was associated with a significant increase in stroke. Based on these findings, future trials must carefully collect stroke to determine safety in addition to efficacy.

Culprit lesion thrombus burden after manual thrombectomy or percutaneous coronary intervention-alone in ST-segment elevation myocardial infarction: the optical coherence tomography sub-study of the TOTAL (ThrOmbecTomy versus PCI ALone) trial

AIMS

Manual thrombectomy has been proposed as a strategy to reduce thrombus burden during primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). However, the effectiveness of manual thrombectomy in reducing thrombus burden is uncertain. In this substudy of the TOTAL (ThrOmbecTomy versus PCI ALone) trial, we compared the thrombus burden at the culprit lesion using optical coherence tomography (OCT) in patients treated with thrombectomy vs. PCI-alone.

METHODS AND RESULTS

The TOTAL trial (N = 10 732) was an international, multicentre, randomized trial of thrombectomy (using the Export catheter, Medtronic Cardiovascular, Santa Rosa, CA, USA) in STEMI patients treated with primary PCI. The OCT substudy prospectively enrolled 214 patients from 13 sites in 5 countries. Optical coherence tomography was performed immediately after thrombectomy or PCI-alone and then repeated after stent deployment. Thrombus quantification was performed by an independent core laboratory blinded to treatment assignment. The primary outcome of pre-stent thrombus burden as a percentage of segment analysed was 2.36% (95% CI: 1.73-3.22) in the thrombectomy group and 2.88% (95% CI: 2.12-3.90) in the PCI-alone group (P = 0.373). Absolute pre-stent thrombus volume was not different (2.99 vs. 3.74 mm(3), P = 0.329). Other secondary outcomes of pre-stent quadrants of thrombus, post-stent atherothrombotic burden, and post-stent atherothrombotic volume were not different between groups.

CONCLUSION

Manual thrombectomy did not reduce pre-stent thrombus burden at the culprit lesion compared with PCI-alone. Both strategies were associated with low thrombus burden at the lesion site after the initial intervention to restore flow.

Decreased apoptosis despite severe CD4 depletion in the thymus of a human immunodeficiency virus-1 infected child

Thymic epithelial space (TES), where thymopoiesis is located, and thymic perivascular space (PVS), where T lymphocytes are pooled, appear differentially involved in human immunodeficiency virus 1 (HIV-1)-infected children. The decline of CD4+ T cells during HIV-1 infection is probably due to a relative predominance of CD4+ T cell destruction on cell proliferation. Antiretroviral therapy (ART) typically increases circulating CD4+ T cell counts, but it is debated whether ART reduces the destruction of existing CD4+ T cells or enhances the production of new cells. We report on postmortem flow-cytometry, immunohistochemistry, and terminal deoxynucleotide transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) studies performed on thymus of an 11-year-old vertically HIV-1 infected child receiving ART. Thymus tissue sections showed that CD4+ and CD8+ cells were more numerous in PVS than in TES (p=0.0334 for CD4+ cells, p<0.0001 for CD8+ cells). Thymus cell suspension showed that CD4+ CD8+ cells (immature thymocytes) were 15.4% (age-related control: 80.5%). Very few apoptotic CD4+ cells were seen in TES. Very low to absent proliferation activity was demonstrated in both TES and PVS. We suggest that 1) lymphocyte depletion in HIV-1 infection is more pronounced in TES than in PVS, 2) immature thymocytes are not enhanced, and 3) an anti-apoptotic effect in the thymus seems to be a potential ART mechanism to explain the CD4+ pool increase.

Transfer for urgent percutaneous coronary intervention early after thrombolysis for ST-elevation myocardial infarction: the TRANSFER-AMI pilot feasibility study

BACKGROUND

Most hospitals in Canada do not have percutaneous coronary intervention (PCI) facilities and use thrombolysis as reperfusion therapy for ST-elevation myocardial infarction (STEMI). Urgent PCI after thrombolysis may optimize reperfusion and prevent reinfarction and recurrent ischemia.

OBJECTIVE

To determine the feasibility of transferring high-risk STEMI patients from community hospitals in Ontario to PCI centres for urgent PCI within 6 h of thrombolysis.

METHODS

Patients with anterior or high-risk inferior STEMI received tenecteplase and were urgently transferred to PCI centres. PCI was performed if at least 70% stenosis was present in the infarct-related artery, regardless of flow, using coronary stents. Transfer of stable patients back to community hospitals was encouraged 24 h to 48 h after PCI.

RESULTS

Eighteen patients were transferred and underwent PCI a median of 3.9 h (range 2.7 h to 6.4 h) after thrombolysis. No complications occurred during transfer. One death occurred that was related to failed reperfusion and cardiogenic shock. Minor access-site bleeding occurred in five patients. Fifteen patients were transferred back to their community hospitals within 24 h of PCI. There were no further deaths or reinfarctions at one-year follow-up.

CONCLUSIONS

Transfer of high-risk STEMI patients for urgent PCI within 6 h after thrombolysis appears feasible. The randomized trial phase of the Trial of Routine ANgioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI) will compare this strategy with standard treatment after thrombolysis.

Radial versus femoral access for rescue percutaneous coronary intervention with adjuvant glycoprotein IIb/IIIa inhibitor use

BACKGROUND

The transradial approach has not been evaluated for "rescue" percutaneous coronary intervention (PCI) with glycoprotein (GP) IIb/IIIa inhibitor following failed thrombolysis.

OBJECTIVES

To compare the safety and procedural outcomes of the transradial and transfemoral approaches to rescue PCI.

METHODS

Rescue PCI cases with adjuvant GP IIb/IIIa inhibitor performed at two centres were reviewed retrospectively, and the bleeding rates, equipment use and procedure times for the femoral and the radial approach were compared.

RESULTS

Radial access was attempted in 47 of 111 cases (42%) and crossover to femoral access was required in two cases (4%). Major bleeding occurred in three patients in the radial group (6%) and in 12 patients in the femoral group (19%; P=0.06). Radial access was associated with less access site-related major bleeding (0% versus 9%; P=0.04) and fewer transfusions (4% versus 19%; P=0.02). After excluding patients with intra-aortic balloon pump, this difference was no longer statistically significant (4% versus 8%; P=0.7). Fluoroscopy times and contrast use were similar, and the time to first balloon inflation was slightly longer with radial access (33 min versus 30 min; P=0.07).

CONCLUSIONS

In selected patients, the transradial approach for rescue PCI is safe and effective. The present findings warrant further study in a prospective, randomized trial.

Pre-procedural plasma levels of C-reactive protein and interleukin-6 do not predict late coronary angiographic restenosis after elective stenting

AIMS

Inflammatory markers may serve as an important prognostic predictor in patients with coronary heart diseases. In patients undergoing coronary interventions, it has been shown that baseline C-reactive protein (CRP) could predict late clinical restenosis. Only a few small studies have examined the possible relationship with angiographic restenosis. In patients with stable angina pectoris,we examined whether baseline CRP and IL-6 predict late coronary angiographic restenosis after stenting.

METHODS AND RESULTS

Pre-procedural plasma levels of CRP and IL-6 were measured in 216 patients with stable angina pectoris undergoing elective coronary stenting. Angiographic follow-up was performed in all patients at 6 months. Baseline CRP levels were 6.15 +/- 0.78 mg/L versus 5.24 +/- 1.17 mg/L in the patent and restenosis groups, respectively (P=0.64). IL-6 levels were 0.46 +/- 0.03 ng/L versus 0.40 +/- 0.07 ng/L in the patent and restenosis groups, respectively (P=0.50). CRP levels were obtained again at the time of angiographic follow-up and were found to be similar in both groups (2.89 +/- 0.29 mg/L versus 2.61 +/- 0.63 mg/L, P=0.72). Moreover, in a sub-group of 43 patients, serial blood samples were obtained at several time points after the procedure up to 6 months. Both CRP and IL-6 plasma levels increased significantly in response to the procedure. CRP levels peaked at 3 days (11.27 +/- 1.53 mg/L versus 4.26 +/- 0.72 mg/L at baseline, P<0.0001). IL-6 levels reached maximum values after 24 h (1.08 +/- 0.14 ng/L versus 0.53 +/- 0.08 ng/L at baseline, P<0.0001). However, in this sub-group of patients, neither peak CRP nor IL-6 levels were found to predict late angiographic restenosis.

CONCLUSIONS

Coronary stenting is associated with transient increases in both CRP and IL-6 levels. However, pre-procedural CRP and IL-6 levels do not predict late coronary angiographic restenosis.

Comparing angiographic coronary revascularization strategies: a 'natural' experiment

OBJECTIVE

To study the impact of intracoronary stents on clinical restenosis in the 'real world'.

DESIGN

Retrospective comparison of the rates of clinical restenosis between two cohorts exposed to different strategies for percutaneous transcatheter intervention. The endpoint was the first of death, myocardial infarction, coronary artery bypass grafting, repeat percutaneous transluminal coronary angioplasty (PTCA) or repeat coronary angiography within nine months.

SETTING

Tertiary care cardiac referral centre serving a large, metropolitan population.

PATIENTS

Patients undergoing angiographic revascularization from January 1 to February 28, 1996 (the 'restricted' group [R], n=147) were compared with a before and after cohort (the 'usual' group [U], n=232, divided into those who underwent revascularization between November 1 and November 30, 1995, and those who underwent revascularization between April 1 and May 31, 1996).

INTERVENTIONS

The R group was revascularized during a period of economic constraint, which imposed a shortage on stent availability. The U cohort underwent revascularization before and after the shortage (an 'unrestricted' environment for stent usage).

MAIN RESULTS

There was no difference in clinical restenosis rates between the R (34.7%) and U (37.9%) groups (P=0.524, OR R/U=0.915, 95% CI 0.694 to 1.206). Also, the rate of clinical restenosis was the same among patients who underwent PTCA without stent insertion (34.8%) and those who received a stent (39.4%) (P=0.368, OR=1.13, 95% CI 0.87 to 1.44).

CONCLUSIONS

At the authors' institution, a restricted stenting policy did not result in a higher clinical restenosis rate than that of usual practice.

Predictors of same-admission cardiac catheterization in patients with acute ischemic syndromes

BACKGROUND

Various strategies exist for the use of cardiac catheterization in unstable angina or non-Q wave myocardial infarction. At the authors' institution, the overall volume of cardiac catheterization has increased in recent years.

OBJECTIVE

To investigate whether this increased volume of cardiac catheterization was due to adoption of a more invasive approach to the management of patients with acute ischemic syndromes.

DESIGN

A retrospective cohort study was conducted using detailed chart review of coronary care unit admissions during 1990/91 and 1993/94.

SETTING

A university-affiliated tertiary care referral centre with facilities for cardiac catheterization.

PATIENTS

One hundred patients randomly selected from among those with unstable angina, non-Q wave myocardial infarction or chest pain not yet diagnosed in each of the study years. Detailed follow-up was complete for all patients.

OUTCOME MEASURE

The use of cardiac catheterization during the index admission was documented.

MAIN RESULTS

There was a trend towards more frequent use of same admission cardiac catheterization in the later period (21% [CI 14% to 31%] versus 12% [CI 7% to 20%], P = 0.09). However, after controlling for baseline characteristics and in-hospital events, the year of admission did not independently predict the use of catheterization (P = 0.60). By multivariate logistic regression, recurrence of chest pain and evidence of myocardial necrosis were most closely associated with same-admission cardiac catheterization.

CONCLUSIONS

Although clinical factors partially explain the increased use of catheterization over time, there may have also been shift towards a more aggressive practice style at the authors' institution. Further study is needed to address this possibility.

Anisotropic scatter patterns and anomalous birefringence of obliquely deposited cerium oxide films

Cerium oxide films formed by electron-beam evaporation onto oblique substrates are shown to scatter light strongly into spatially anisotropic distributions and to exhibit large normal-incidence birefringence Δ n = n(s) - n(p). The apparatus for direct recording of a useful projection of the scatter distributions is described. Characteristic differences in scatter patterns recorded for cerium oxide, relative to those from tilted columnar titania and zirconia films, are believed to be associated with unusual microstructures recorded for cerium oxide films by scanning electron microscopy. With increasing angle of deposition, the microstructure of cerium oxide was observed to change from densely packed columns to partially isolated needlelike columns at angles that do not obey the tangent rule. In particular, deposition at 55° yielded columns nearly perpendicular to the substrate, yet the normal-incidence birefringence was large. The retardation of the films was recorded as a function of angle of incidence for propagation in the deposition plane. A turning point near 0° incidence for the 55° film confirmed that one principal axis is perpendicular to the substrate. Significant bunching of columns into rows running perpendicular to the deposition plane was recorded by scanning electron microscopy and may account for both the scatter and the birefringence.

Modal contours for biaxial thin-film waveguides

The modal characteristics of a general tilted columnar biaxial thin-film waveguide are displayed by the plots of both Snell's law quantity β = n sin θ and the polarization of the evanescent field at the cover interface on a polar diagram. The association of characteristic features in the modal diagram with the basis fields is demonstrated, and the mechanism that allows p and s modes propagating in the deposition plane to overlap, without the modal contours crossing, is explored.

Relation between light scattering and the microstructure of optical thin films

Special substrate-film designs are used to measure roughness-induced scattering and scattering from the volume of optical thin films separately. So theoretical models of surface roughness and volume scattering become applicable to the experimental data, and quantitative information on thin-film microstructure can be derived. Measuring total integrated and angle-resolved scattering on oxide, fluoride, and chalcogenide films of different film thicknesses yields the evolution law of microstructural growth, which for the majority of investigated films roughly follows a square-root dependence on film thickness. Packing densities of fluoride films calculated from volume-scattering data are found to agree with results from quartz-crystal monitoring.

Light scattering from the volume of optical thin films: theory and experiment

A theoretical model is presented that describes the volume scattering in thin optical films, particularly in typical columnar structures. It is based on a first-order perturbation theory that concerns the fluctuation of the dielectric permittivity in the film. For evaporated PbF(2) films that show a pronounced columnar morphology, angular as well as total integrated scattering measurements at lambda = 633 nm have been performed on a special layer design to suppress roughness-induced scattering. A comparison of the predicted theoretical and the measured experimental values leads to such structural parameters as packing density and the evolutionary exponent of the columns.

[Acute myeloblastosis in von Jaksch-Luzet syndrome]

A 7 month-old infant of Italian origin, who was given a vitamin-D deficient diet developed a Von Jaksch-Luzet syndrome with more than 20% myeloblasts in the bone marrow. Plasma levels of vitamin D metabolites wer low and parathormone levels were high. A low dose of vitamin D3 (2,000 IU cholecalciferol/day) resulted in the recovery of a normal phosphocalcic balance and in the disappearance of myeloblastosis.

Shigella and shigellaemia

Two cases of bacteraemia with Shigella flexneri 2a in children are described. They illustrate the wide variety of clinical manifestations of shigellosis, ranging from benign gastroenteritis to septicaemia associated with severe extra-intestinal manifestations.