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Relation of vascular dilator function and cardiac autonomic function with coronary angiography findings in patients with non-ST segment elevation acute coronary syndrome
No full textBackground: A sizeable number of patients with a diagnosis of non-ST segment elevation acute coronary syndrome show non-obstructive coronary artery disease. In this study we assessed whether differences in vascular and cardiac autonomic function exist between non-ST segment elevation acute coronary syndrome patients with obstructive or non-obstructive coronary artery disease. Methods and results: Systemic endothelium-dependent and independent vascular dilator function (assessed by flow-mediated dilation and nitrate-mediated dilation of the brachial artery, respectively) and cardiac autonomic function (assessed by time-domain and frequency-domain heart rate variability parameters) were assessed on admission in 120 patients with a diagnosis of non-ST segment elevation acute coronary syndrome. Patients were divided into two groups according to coronary angiography findings: (a) 59 (49.2%) with obstructive coronary artery disease (≥50% stenosis in any epicardial arteries); (b) 61 (50.8%) with non-obstructive coronary artery disease. No significant differences between the two groups were found in both flow-mediated dilation (5.03 ± 2.6 vs. 5.40 ± 2.5%, respectively; P = 0.37) and nitrate-mediated dilatation (6.79 ± 2.8 vs. 7.30 ± 3.4%, respectively; P = 0.37). No significant differences were also observed between the two groups both in time-domain and frequency-domain heart rate variability variables, although the triangular index tended to be lower in obstructive coronary artery disease patients (30.2 ± 9.5 vs. 33.9 ± 11.6, respectively; P = 0.058). Neither vascular nor heart rate variability variables predicted the recurrence of angina, requiring emergency room admission or re-hospitalisation, during 11.3 months of follow-up. Conclusions: Among patients admitted with a diagnosis of non-ST segment elevation acute coronary syndrome we found no significant differences in systemic vascular dilator function and cardiac autonomic function between those with obstructive coronary artery disease and those with non-obstructive coronary artery disease
Microvascular angina: ― Long-term exercise stress test follow-up ―
No full textBackground: A sizeable proportion of patients with primary stable microvascular angina (MVA; exercise-induced angina, positive exercise stress test [EST], normal coronary arteries) have recurrent symptoms during follow-up. There have been no previous studies, however, on the long-term results of EST and their correlation with symptom outcome. Methods and Results: Follow-up EST was performed in 71 MVA patients at an average of 16.2 years (range, 5–25 years) from the first EST. Angina status was assessed on weekly frequency of angina episodes and nitroglycerin consumption and by whether symptoms had worsened, improved, or remained unchanged over time. At follow-up EST, 41 patients (group 1) had exercise-induced ischemia, whereas 30 patients (group 2) had negative EST. Compared to group 2, group 1 patients more frequently had exercise-induced dyspnea, and had a greater maximum ST-segment depression and a lower coronary blood flow response to adenosine and cold pressor test, but group 2 patients had a more frequent history of rest angina. No differences between the 2 groups were found at follow-up in angina status or change in symptom status during follow-up. Conclusions: Electrocardiogram results improve significantly in a sizeable proportion of patients with MVA. Changes in EST results, however, were not associated with clinical outcome
Clinical Spectrum and Outcome of Patients With Non-ST-Segment Elevation Acute Coronary Syndrome and No Obstructive Coronary Atherosclerosis
No full textBackground: Because approximately 10% of patients with no-ST-segment elevation acute coronary syndrome (NSTE-ACS) show no obstructive coronary artery disease (NOCAD) on angiography, we assessed the spectrum of diagnoses and the predictors of outcome of these patients. Methods and
Results: We studied 178 patients admitted to a coronary care unit with an initial diagnosis of NSTEACS, based on clinical, ECG and laboratory data, but found to have NOCAD. The final diagnosis in these patients was heterogeneous; true NSTE-ACS (ie, coronary thrombosis on an unstable plaque) was ascertained in 1 patient (0.6%), whereas diagnosis at discharge was microvascular NSTE-ACS in 56.2% of patients, variant angina in 10.1%, myocarditis in 8.9%, takotsubo disease in 7.9%, tachyarrhythmia-related chest pain in 6.7%, and non-cardiac pain in 9.6%. At 24.5-month follow-up, 21 deaths (11.8%) had occurred, 9 (5.1%) from cardiovascular causes, including 2 (1.12%) coronary deaths. By multivariable Cox analysis, age only predicted global (hazard ratio [HR] 1.07 [1.02-1.12]; P=0.006) and cardiovascular (HR 1.08 [1.01-1.16]; P=0.04) mortality; non-coronary vascular disease was the main predictor of cardiovascular death or readmission for cardiovascular disease (HR 3.28 [1.75-6.14]; P<0.001) and coronary death or readmission for angina (HR 3.20 [1.26-8.14]; P=0.014).
Conclusions: Patients with an initial diagnosis of NSTE-ACS constitute a heterogeneous population with different final diagnoses. Patients have a rather high rate of fatal events, most of which, however, are not related to coronary causes
Effect of Remote Ischemic Preconditioning on Coronary Procedure-Related Impairment of Vascular Dilator Function
No full textN/
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Poor tolerance and limited effects of isosorbide-5-mononitrate in microvascular angina
No full textOBJECTIVES:
To assess the effects of isosorbide-5-mononitrate (ISMN) in patients with microvascular angina (MVA).
METHODS:
We randomized 20 MVA patients, treated with a β-blocker or a calcium antagonist, to 60 mg slow-release ISMN (halved to 30 mg if not tolerated) or placebo once a day for 4 weeks; the patients were then switched to the other treatment for another 4 weeks. Their clinical status was assessed with the Seattle Angina Questionnaire (SAQ) and the EuroQoL score for quality of life. The exercise stress test (EST), coronary blood flow (CBF) response to nitrate and the cold pressor test (CPT), brachial artery flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) were also assessed.
RESULTS:
Nine patients (45%) did not complete the ISMN phase due to side effects; 2 patients refused a follow-up. Nine patients completed the study. The SAQ and EuroQoL scores were significantly better with ISMN than with placebo, although the differences were small. No differences were found between the treatments in the EST results, CBF response to nitroglycerin (p = 0.55) and the CPT (p = 0.54), FMD (p = 0.26) and NMD (p = 0.35).
CONCLUSIONS:
In this study, a high proportion of MVA patients showed an intolerance to ISMN; in those tolerating the drug, significant effects on their angina status were observed, but the benefit appeared to be modest and independent of effects on coronary microvascular function
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