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"Cardiovascular Medicine"
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Pool size ratio of the substantia nigra in Parkinson’s disease derived from two different quantitative magnetization transfer approaches
Purpose
We sought to measure quantitative magnetization transfer (qMT) properties of the substantia nigra pars compacta (SNc) in patients with Parkinson’s disease (PD) and healthy controls (HCs) using a full qMT analysis and determine whether a rapid single-point measurement yields equivalent results for pool size ratio (PSR).
Methods
Sixteen different MT-prepared MRI scans were obtained at 3 T from 16 PD patients and eight HCs, along with B1, B0, and relaxation time maps. Maps of PSR, free and macromolecular pool transverse relaxation times (
T
2
f
,
T
2
m
) and rate of MT exchange between pools (
k
mf
) were generated using a full qMT model. PSR maps were also generated using a single-point qMT model requiring just two MT-prepared images. qMT parameter values of the SNc, red nucleus, cerebral crus, and gray matter were compared between groups and methods.
Results
PSR of the SNc was the only qMT parameter to differ significantly between groups (
p
< 0.05). PSR measured via single-point analysis was less variable than with the full MT model, provided slightly better differentiation of PD patients from HCs (area under curve 0.77 vs. 0.75) with sensitivity of 0.75 and specificity of 0.87, and was better than transverse relaxation time in distinguishing PD patients from HCs (area under curve 0.71, sensitivity 0.87, and specificity 0.50).
Conclusion
The increased PSR observed in the SNc of PD patients may provide a novel biomarker of PD, possibly associated with an increased macromolecular content. Single-point PSR mapping with reduced variability and shorter scan times relative to the full qMT model appears clinically feasible.
Journal Article
Early Changes of Myocardial Function After Transcatheter Aortic Valve Implantation Using Multilayer Strain Speckle Tracking Echocardiography
Transcatheter aortic valve implantation (TAVI) is an effective therapeutic option for severe symptomatic aortic valve stenosis (AS) with intermediate or high surgical risk. The purpose of this study was to examine the effects of TAVI on left ventricular (LV) mechanics using multilayer global longitudinal strain (GLS) by 2D speckle-tracking echocardiography. A total of 119 patients (mean age 83 ± 7.0 years, male 54%) with severe symptomatic AS and normal LV ejection fraction (LVEF) underwent echocardiography at baseline and 1 month after TAVI. Global longitudinal strain was measured from the endocardial layer (GLSendo), mid-ventricular layer (GLSmyo), epicardial layer (GLSepi) and full thickness of myocardium (GLSwhole). There was significant improvement in all 3 layers of GLS after TAVI compared with baseline, but there was no significant change in LVEF. The relative % increment in GLS in each layer strain were 11.2 ± 23.4% (GLSendo), 13.4 ± 33.0% (GLSmyo) and 18.0 ± 46.6% (GLSepi) with significant difference between GLSendo and GLSepi (p < 0.05). In conclusion, multilayer GLS is more sensitive than conventional LVEF to detect early improvement in LV systolic function after TAVI in patients with severe AS. There is a disproportional improvement in different layers with least improvement in the endocardium. Multilayer strain analysis may provide new insights into understanding mechanics of AS.
Journal Article
Real-time use of instantaneous wave–free ratio: Results of the ADVISE in-practice: An international, multicenter evaluation of instantaneous wave–free ratio in clinical practice
To evaluate the first experience of real-time instantaneous wave–free ratio (iFR) measurement by clinicians.
The iFR is a new vasodilator-free index of coronary stenosis severity, calculated as a trans-lesion pressure ratio during a specific period of baseline diastole, when distal resistance is lowest and stable. Because all previous studies have calculated iFR offline, the feasibility of real-time iFR measurement has never been assessed.
Three hundred ninety-two stenoses with angiographically intermediate stenoses were included in this multicenter international analysis. Instantaneous wave–free ratio and fractional flow reserve (FFR) were performed in real time on commercially available consoles. The classification agreement of coronary stenoses between iFR and FFR was calculated.
Instantaneous wave–free ratio and FFR maintain a close level of diagnostic agreement when both are measured by clinicians in real time (for a clinical 0.80 FFR cutoff: area under the receiver operating characteristic curve [ROCAUC] 0.87, classification match 80%, and optimal iFR cutoff 0.90; for a ischemic 0.75 FFR cutoff: iFR ROCAUC 0.90, classification match 88%, and optimal iFR cutoff 0.85; if the FFR 0.75-0.80 gray zone is accounted for: ROCAUC 0.93, classification match 92%). When iFR and FFR are evaluated together in a hybrid decision-making strategy, 61% of the population is spared from vasodilator while maintaining a 94% overall agreement with FFR lesion classification.
When measured in real time, iFR maintains the close relationship to FFR reported in offline studies. These findings confirm the feasibility and reliability of real-time iFR calculation by clinicians.
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Journal Article
A Journal Club Format That Combines Literature Reading and Clinical Cases Is More Conducive to Improving Senior Undergraduate Medical Students’ Overall Competence
Journal clubs have proved to be very important in postgraduate education. This method is based on a problem-oriented teaching methodology. However, it is less commonly used in teaching undergraduate medical students. The aim of our study was to apply a journal club learning format in the teaching of cardiovascular medicine to senior undergraduate students and to assess the improvement of students' knowledge and skills in evidence-based medicine after participation in the journal club.
Participants were selected on a voluntary basis. A total of 30 undergraduate medical students were selected (15 students each from the fourth and fifth years). Each student was required to complete five journal club activities within 2 years. For each journal club activity, an instructor and two students were assigned to report separately. The content of the instructor's report was the analysis of a typical clinical case or the diagnosis and treatment standard and new development of the related disease. The literature reported by the students should be related to the case or new development reported by the teacher.
Changes in students who participated in the journal club before and after the training were assessed using student self-assessments, student peer assessments, teacher assessments, and modified EPIC scale assessments. Statistical analysis showed that students' verbal expression, teamwork, intellectual curiosity, analytical skills, slide production, doctor-patient communication, clinical thinking, and research thinking improved significantly after participating in the journal club (
<0.001).
Participation in journal clubs by undergraduate medical students improved students' knowledge and skills in evidence-based medicine. A journal club format that combines literature reading and clinical cases is conducive to improving students' overall competence.
Journal Article
HFA of the ESC position paper on the management of LVAD‐supported patients for the non‐LVAD specialist healthcare provider Part 3: at the hospital and discharge
The growing population of left ventricular assist device (LVAD)‐supported patients increases the probability of an LVAD‐ supported patient hospitalized in the internal or surgical wards with certain expected device related, and patient‐device interaction complication as well as with any other comorbidities requiring hospitalization. In this third part of the trilogy on the management of LVAD‐supported patients for the non‐LVAD specialist healthcare provider, definitions and structured approach to the hospitalized LVAD‐supported patient are presented including blood pressure assessment, medical therapy of the LVAD supported patient, and challenges related to anaesthesia and non‐cardiac surgical interventions. Finally, important aspects to consider when discharging an LVAD patient home and palliative and end‐of‐life approaches are described.
Journal Article
Sevoflurane
Sevoflurane has been available for clinical practice for about 20 years. Nowadays, its pharmacodynamic and pharmacokinetic properties together with its absence of major adverse side effects on the different organ systems have made this drug accepted worldwide as a safe and reliable anesthetic agent for clinical practice in various settings.
Journal Article
Quantitative assessment of the stent/scaffold strut embedment analysis by optical coherence tomography
The degree of stent/scaffold embedment could be a surrogate parameter of the vessel wall-stent/scaffold interaction and could have biological implications in the vascular response. We have developed a new specific software for the quantitative evaluation of embedment of struts by optical coherence tomography (OCT). In the present study, we described the algorithm of the embedment analysis and its reproducibility. The degree of embedment was evaluated as the ratio of the embedded part versus the whole strut height and subdivided into quartiles. The agreement and the inter- and intra-observer reproducibility were evaluated using the kappa and the interclass correlation coefficient (ICC). A total of 4 pullbacks of OCT images in 4 randomly selected coronary lesions with 3.0 × 18 mm devices [2 lesions with Absorb BVS and 2 lesions with XIENCE (both from Abbott Vascular, Santa Clara, CA, USA)] from Absorb Japan trial were evaluated by two investigators with QCU-CMS software version 4.69 (Leiden University Medical Center, Leiden, The Netherlands). Finally, 1481 polymeric struts in 174 cross-sections and 1415 metallic struts in 161 cross-sections were analyzed. Inter- and intra-observer reproducibility of quantitative measurements of embedment ratio and categorical assessment of embedment in Absorb BVS and XIENCE had excellent agreement with ICC ranging from 0.958 to 0.999 and kappa ranging from 0.850 to 0.980. The newly developed embedment software showed excellent reproducibility. Computer-assisted embedment analysis could be a feasible tool to assess the strut penetration into the vessel wall that could be a surrogate of acute injury caused by implantation of devices.
Journal Article
Myocarditis and inflammatory cardiomyopathy: current evidence and future directions
Inflammatory cardiomyopathy, characterized by inflammatory cell infiltration into the myocardium and a high risk of deteriorating cardiac function, has a heterogeneous aetiology. Inflammatory cardiomyopathy is predominantly mediated by viral infection, but can also be induced by bacterial, protozoal or fungal infections as well as a wide variety of toxic substances and drugs and systemic immune-mediated diseases. Despite extensive research, inflammatory cardiomyopathy complicated by left ventricular dysfunction, heart failure or arrhythmia is associated with a poor prognosis. At present, the reason why some patients recover without residual myocardial injury whereas others develop dilated cardiomyopathy is unclear. The relative roles of the pathogen, host genomics and environmental factors in disease progression and healing are still under discussion, including which viruses are active inducers and which are only bystanders. As a consequence, treatment strategies are not well established. In this Review, we summarize and evaluate the available evidence on the pathogenesis, diagnosis and treatment of myocarditis and inflammatory cardiomyopathy, with a special focus on virus-induced and virus-associated myocarditis. Furthermore, we identify knowledge gaps, appraise the available experimental models and propose future directions for the field. The current knowledge and open questions regarding the cardiovascular effects associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are also discussed. This Review is the result of scientific cooperation of members of the Heart Failure Association of the ESC, the Heart Failure Society of America and the Japanese Heart Failure Society.In this Review, Tschöpe and colleagues summarize and evaluate the available evidence on the pathogenesis, diagnosis and treatment of myocarditis and inflammatory cardiomyopathy, with special focus on virus-induced and virus-associated myocarditis. The authors also identify knowledge gaps, appraise available experimental models and propose future directions for the field.
Journal Article
Lack of an association or an inverse association between low-density-lipoprotein cholesterol and mortality in the elderly: a systematic review
ObjectiveIt is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue.Setting, participants and outcome measuresWe sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥60 years from the general population.ResultsWe identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between all-cause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found.ConclusionsHigh LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies.
Journal Article