Search

Heart failure is a major health risk, and with limited availability of donor organs, there is an increasing need for developing cardiac assist devices (CADs). Mock circulatory loops (MCL) are an important in-vitro test platform for CAD’s performance assessment and optimisation. The MCL is a lumped parameter model constructed out of hydraulic and mechanical components aiming to simulate the native cardiovascular system (CVS) as closely as possible. Further development merged MCLs and numerical circulatory models to improve flexibility and accuracy of the system; commonly known as hybrid MCLs. A total of 128 MCLs were identified in a literature research until 25 September 2020. It was found that the complexity of the MCLs rose over the years, recent MCLs are not only capable of mimicking the healthy and pathological conditions, but also implemented cerebral, renal and coronary circulations and autoregulatory responses. Moreover, the development of anatomical models made flow visualisation studies possible. Mechanical MCLs showed excellent controllability and repeatability, however, often the CVS was overly simplified or lacked autoregulatory responses. In numerical MCLs the CVS is represented with a higher order of lumped parameters compared to mechanical test rigs, however, complex physiological aspects are often simplified. In hybrid MCLs complex physiological aspects are implemented in the hydraulic part of the system, whilst the numerical model represents parts of the CVS that are too difficult to represent by mechanical components per se. This review aims to describe the advances, limitations and future directions of the three types of MCLs.

Background/objectives Evidence regarding the influence of coffee on appetite and weight control is equivocal and the influence of covariates, such as genetic variation in caffeine metabolism, remains unknown. Herein, we addressed the novel hypothesis that genetic variation in CYP1A2, a gene responsible for more than 95% of caffeine metabolism, differentially impacts the association of coffee consumption with appetite and BMI among individuals with different genetic predispositions to obesity. Subjects/methods A cross-over randomized intervention study involving 18 volunteers assessed the effects of coffee consumption on dietary intake, appetite, and levels of the appetite-controlling hormones asprosin and leptin. Data on habitual coffee intake, BMI, and perceived appetite were obtained from an observational cohort of 284 volunteers using validated questionnaires. Participants were stratified according to a validated genetic risk score (GRS) for obesity and to the -163C > A (rs762551) polymorphism of CYP1A2 as rapid (AA), intermediate (AC), or slow (CC) caffeine metabolizers. Results Coffee consumption led to lower energy and dietary fat intake and circulating asprosin levels (P for interaction of rs762551 genotype*coffee consumption=0.056, 0.039, and 0.043, respectively) as compared to slow/intermediate metabolizers. High coffee consumption was more prevalent in rapid compared to slow metabolizers (P = 0.008 after adjustment for age, sex, and BMI) and was associated with lower appetite perception and lower BMI only in rapid metabolizers (P for interaction of rs762551 genotype*coffee consumption = 0.002 and 0.048, respectively). This differential association of rs762551 genotype and coffee consumption with BMI was more evident in individuals at higher genetic risk of obesity (mean adjusted difference in BMI = -5.82 kg/m2 for rapid versus slow/intermediate metabolizers who consumed more than 14 cups of coffee per week). Conclusions CYP1A2 rs762551 polymorphism modifies the association of habitual coffee consumption with BMI, in part by influencing appetite, energy intake and circulating levels of the orexigenic hormone asprosin. This association is more evident in subjects with high genetic predisposition to obesity. ClinicalTrials.gov: registered Clinical Trial NCT04514588.

Background To minimize complications associated with the construction of the hand-sewn aortic anastomosis, alternative experimental methods have been pursued. This study aimed to evaluate the efficacy of experimental anastomotic devices in relation to time and point of rupture of the anastomosis in comparison to the conventional technique. Materials and methods An electronic search was performed using MEDLINE, Scopus, Science Direct, and Cochrane Library databases by two independent authors. Our exclusion criteria referred to studies reporting results solely from end-to-side anastomosis, results on vessels other than the aorta, studies that did not involve animal experiments, and non-English publications. The last search date was January 1, 2020. Results The meta-analysis included 22 studies with 34 anastomosis samples and a total of 316 animals. The pooled mean automated anastomosis time was 10.38 min, and the mean point of rupture was 32.7 N. In the subgroup analysis of automated anastomosis time by device category, the anastomotic stenting technique reported significantly lower anastomosis time but also showed significantly lower point of rupture. Comparing the efficacy of experimental devices and the hand-sewn technique, our pooled analysis showed that automated devices significantly decrease the time needed to perform the anastomosis (weighted mean difference −7.24 min). On the other hand, the automated anastomosis is also associated with decreased tensile strength (weighted mean difference −20.68 N). Conclusions Although experimental devices seem to offer a faster anastomosis, they lack endurance when compared with the hand-sewn technique. Further research is needed for the development of an “ideal” anastomotic technique.

Coronavirus disease-19 (COVID-19) has extended implications namely the long COVID-19 syndrome. We assessed over-time changes in left ventricular (LV) function, aortic stiffness, autonomic function, and ventricular-arterial coupling (VAC) in post-COVID-19 patients. We followed 34 post-COVID-19 subjects, up to 6 months post-hospital discharge. Subjects without COVID-19 served as control. We evaluated LV global longitudinal strain (LV-GLS), arterial stiffness [carotid-femoral pulse wave velocity (cf-PWV)], and heart rate variability -standard deviation of normal RR intervals (SDNN). VAC was estimated as the ratio of cf-PWV to LV-GLS. Post-COVID-19 individuals (1-month post-hospital discharge) presented with impaired LV-GLS [-18.4%(3.1) vs. -22.0%(2.7), P 0.001], cf-PWV [12.1 m/s (3.2) vs. 9.6 m/s (1.9), P 0.001], SDNN [111.3 ms (22.6) vs. 147.2 ms (14.0), P 0.001], and VAC [-0.68 (0.22) vs. -0.44 (0.10), P 0.001] compared to control. LV-GLS, SDNN, and VAC improved at the 6-month follow-up however they did not reach control levels. In post-COVID-19 subjects, SDNN and VAC were correlated at the 1-month (R = 0.499, P = 0.003) and 6-month (R = 0.372, P = 0.04) follow-up. Long COVID-19 syndrome was associated with impaired LV-GLS, SDNN, and VAC. Post-COVID-19 subjects presented with autonomic dysregulation associated with aortic stiffness, ventricular-arterial impairment, and LV dysfunction, even 6-months post-hospital discharge. These abnormalities may be related to the presence of long COVID-19 syndrome.

Graphical abstract, Highlights • Colchicine is among the oldest drug molecules in medical history. • Clinicians should always check for drug to drug interactions and modify colchicine’s dose according to published guidelines. • Beyond known indications (e.g. pericarditis, gout), current evidence implies favorable colchicine effects in CAD, stroke and even in COVID19., Colchicine’s medical evolution is historically bound to the Mediterranean basin, since remarkable researchers from this region underscored its valuable properties. With the passing of years colchicine became an essential pharmaceutical substance for the treatment of rheumatologic and cardiovascular diseases. In light of recent findings, the therapeutic value of colchicine has grown. In clinical practice, colchicine remains underutilized in view of its proven efficacy and safety. Its complex pharmacokinetics and multifaceted anti-inflammatory role remain under investigation. The current review addresses the safe administration of colchicine in view of key drug to drug interactions. Finally, we are briefly presenting colchicine’s future potential applications.

Aim To characterize different patterns of variability of three repeated within-visit blood pressure (BP) readings and to determine the prevalence of specific variation trends in systolic (SBP), diastolic (DBP) blood pressure and pulse pressure (PP). Methods Data from 53 737 subjects from the National Health and Nutrition Examination Survey were analyzed. In each subject, three consecutive BP measurements were performed with a minimum time-interval of at least 30 s. We propose three patterns of within-visit BP variability (separately for SBP, DBP and PP): (1) increasing trend (BP3 > BP2 > BP1); (2) decreasing trend (BP1 > BP2 > BP3) and (3) no trend (BP3 ≈ BP2 ≈ BP1). A threshold of minimum change (ΔP > 3 mmHg) between BP1-BP2 and BP2-BP3 was also applied as a prerequisite for the definition of these trends. Results An increasing trend was observed among three consecutive measurements of SBP, DBP and PP in 7.4, 10.4 and 10.2%, respectively. When a minimum threshold of 3 mmHg was set the respective increasing trends were observed in 1.8, 2.9 and 4.4%, respectively. There was a higher prevalence of decreasing trend within three consecutive SBP, DBP and PP readings: 17, 13.1 and 16.2%, respectively, whereas using a threshold of ΔP >3 mmHg the respective prevalence was 6.3, 4.1 and 7.7%. A maximum absolute difference >10 mmHg within triplicate of SBP/DBP/PP readings was observed in 12.9, 13 and 29.4%, respectively. In the era of personalized medicine, these patterns are well worth further investigation concerning their pathophysiologic and clinical relevance.

Transcatheter aortic valve implantation (TAVI) led to the foundation of the subspecialty of structural heart interventions and created an emerging area of clinical and technical issues. Soon after TAVI introduction into clinical practice, boundaries were expanded with utilization of valve-in-valve (V-i-V) techniques. V-i-V comprised a diverse subset of patients including TAVI within TAVI, TAVI within a degenerated surgically implanted bioprosthesis, or even TAVI-in-TAVI-in-surgical bioprosthesis. In the present review, we summarize the available literature and present initial experience on the field in Greece.

Coronavirus disease-19 (COVID-19) is implicated by active endotheliitis, and cardiovascular morbidity. The long-COVID-19 syndrome implications in atherosclerosis have not been elucidated yet. We assessed the immediate, intermediate, and long-term effects of COVID-19 on endothelial function.In this prospective cohort study, patients hospitalized for COVID-19 at the medical ward or Intensive Care Unit (ICU) were enrolled and followed up to 6 months post-hospital discharge. Medical history and laboratory examinations were performed while the endothelial function was assessed by brachial artery flow-mediated dilation (FMD). Comparison with propensity score-matched cohort (control group) was performed at the acute (upon hospital admission) and follow-up (1 and 6 months) stages.Seventy-three patients diagnosed with COVID-19 (37% admitted in ICU) were recruited. FMD was significantly (p 0.001) impaired in the COVID-19 group (1.65 ± 2.31%) compared to the control (6.51 ± 2.91%). ICU-treated subjects presented significantly impaired (p = 0.001) FMD (0.48 ± 1.01%) compared to those treated in the medical ward (2.33 ± 2.57%). During hospitalization, FMD was inversely associated with Interleukin-6 and Troponin I (p 0.05 for all). Although, a significant improvement in FMD was noted during the follow-up (acute: 1.75 ± 2.19% vs. 1 month: 4.23 ± 2.02%, vs. 6 months: 5.24 ± 1.62%; p = 0.001), FMD remained impaired compared to control (6.48 ± 3.08%) at 1 month (p 0.001) and 6 months (p = 0.01) post-hospital discharge.COVID-19 patients develop a notable endothelial dysfunction, which is progressively improved over a 6-month follow-up but remains impaired compared to healthy controls subjects. Whether chronic dysregulation of endothelial function following COVID-19 could be accompanied by a residual risk for cardiovascular and thrombotic events merits further research.

Background The use of atropine during dobutamine stress echocardiography (DSE) is contraindicated in persons with narrow angle glaucoma though there is limited evidence that low doses of intravenous atropine do not cause pupillary dilation. Objective The aim of this study is to investigate whether atropine when administered in persons without glaucoma during dobutamine stress echocardiography causes pupillary dilation. Methods and Results Out of 144 patients without a history of glaucoma referred for DSE for clinical indications, 105 patients received intravenous atropine doses ranging from 0.1 mg to 1.25 mg (most patients received 0.25–0.75 mg). Pupil diameter of both eyes was measured under the same light conditions before and after the DSE using a CP-30 Optical Digital PD Ruler. For the total of 210 examined eyes pupil diameter remained unaltered after each DSE test (3.65 ± 0.799 mm before vs 3.63 ± 0.766 mm after, p = .737). Similarly, pupil diameter remained unchanged when left and right eyes were assessed separately (right eye: 3.770 ± 0.812 before vs 3.752 ± 0.745 mm after, p = .821 and left eye: 3.521 ± 0.770 before vs 3.499 ± 0.770 mm after, p = .806). Diameter of right and left pupil were also unaltered after grouping patients by sex and iris pigmentation. Age, weight, atropine dose and propranolol dose were not correlated with changes in pupil diameter. Conclusion Intravenous atropine in usual doses administered in DSE does not cause mydriasis in adults without glaucoma. Future studies need to confirm our findings and expand the investigation regarding safety of atropine use during DSE in patients with narrow angle glaucoma.

Background: Hand-sewn anastomosis is a crucial part of aortic reconstruction surgery and significantly affects its outcome. The present study presents a novel, bidirectional surgical needle aimed to improve aortic anastomosis in terms of speed and ease of use. Our objective was to assess the efficacy of the new design in comparison with the conventional needle. Methods: A series of simulations were conducted with COMSOL software in order to perform a fatigue comparative analysis between the new and the conventional needle design. Ease of penetration into a piece of polydimethylsiloxane was evaluated. Lastly, the prototype was tested under in-vitro conditions in comparison with the conventional needle. Results: Based on fatigue analysis, the new needle design improves durability, provided the two tips are equally used. The polytetrafluoroethylene coating improves penetration into the tissue by 7% to 17%, while electropolishing improves penetration up to 19%. When using the novel needle design, the average anastomotic task completion time was significantly reduced by 22% and the overall distance of hand movements was significantly reduced by 20%. Conclusions: The proposed design exhibited a shorter anastomotic time and seems promising in relation to ease of use and simplicity of the anastomotic technique it introduces.

Objective:Accurate and easy to use methods for dietary Na intake estimation in population level are lacking. We aimed at (i) estimating the mean Na intake in the group level using a variety of dietary methods (DM) and urinary methods (UM) and correlating them with 24-h urine collection (24UCol) and (ii) improving the accuracy of the existing DM.Design:The most common DM (three 24-h dietary recalls (24DR) and FFQ) and UM (24UCol and spot urine collection using common equations) were applied. To improve the existing: (i) 24DR, discretionary Na was quantified using salt-related questions or adding extra 15 % in total Na intake and (ii) FFQ, food items rich in Na and salt-related questions were added in the standard questionnaire (NaFFQ).Setting:National and Kapodistrian University of Athens, Greece.Participants:Totally, 122 high cardiovascular risk subjects (56·0 ± 12·6 years; 55·7 % males).Results:Mean 24 h Na excretion (24UNa) was 2810 ± 1304 mg/d. Spot urine methods overestimated the 24UNa (bias range: −1781 to −492 mg) and were moderately correlated to 24UCol (r = 0·469–0·596, P ≤ 0·01). DM underestimated the 24UNa (bias range: 877 to 1212 mg) and were weakly correlated with 24UCol. The improved DM underestimated the 24UNa (bias range: 877 to 923 mg). The NaFFQ presented the smallest bias (−290 ± 1336 mg) and the strongest correlation with 24UCol (r = 0·497, P ≤ 0·01), but wide limits of agreement in Bland–Altman plots (−2909 mg; 2329 mg), like all the other methods did.Conclusions:The existing methods exhibit poor accuracy. Further improvement of the newly developed NaFFQ could be promising for more accurate estimation of mean dietary Na intake in epidemiological studies. Additional validation studies are needed.

Non-invasive monitoring of cardiac output is a technological and clinical challenge, especially for critically ill, surgically operated, or intensive care unit patients. A brachial cuff-based, automated, oscillometric device used for blood pressure and arterial stiffness ambulatory monitoring (Mobil-O-Graph) provides a non-invasive estimation of cardiac output values simultaneously with regular blood pressure measurement. The aim of the study was to evaluate the feasibility of this apparatus to estimate cardiac output in intensive care unit patients and to compare the non-invasive estimated cardiac output values with the respective gold standard method of thermodilution during pulmonary artery catheterization. Repeated sequential measurements of cardiac output were performed, in random order, by thermodilution (reference) and Mobil-O-Graph (test), in 24 patients hospitalized at intensive care unit. Reproducibility and accuracy of the test device were evaluated by Bland–Altman analysis, intraclass correlation coefficient, and percentage error. Mobil-O-Graph underestimated significantly the cardiac output by −1.12 ± 1.38 L/min ( p 0.7 indicating a fair agreement between the test and the reference methods, while percentage error was approximately 39% which is considered to be within the acceptable limits. Cardiac output measurements were reproducible by both Mobil-O-Graph (intraclass correlation coefficient = 0.73 and percentage error = 27.9%) and thermodilution (intraclass correlation coefficient = 0.91 and percentage error = 26.7%). We showed for the first time that cardiac output estimation in intensive care unit patients using a non-invasive, automated, oscillometric, cuff-based apparatus is reproducible (by analyzing two repeated cardiac output measurements), exhibiting similar precision to thermodilution. However, the accuracy of Mobil-O-Graph (error compared to thermodilution) could be considered fairly acceptable. Future studies remain to further examine the reliability of this technology in monitoring cardiac output or stroke volume acute changes which is a more clinically relevant objective.

Wave reflection at central arteries consists of a major component of left ventricular afterload. Central augmentation index (AIx) is the most widely used surrogate of wave reflection. Recent technological developments now provide the ability to obtain, non‐invasively, aortic, or carotid pressure waves and measure AIx based on various algorithms of pulse wave analysis. The aim of this study was to compare AIx measurements performed by the Arteriograph, Complior, and Mobil‐O‐Graph apparatuses. Recordings by each device in randomized order were performed with 5‐minute interval at 211 individuals (age 55.1 ± 14.1 years, 67.8% males) who underwent diagnostic cardiovascular assessment. All measurements were obtained at the supine position, and AIx was calculated using the formula AIx = 100 × (Augmentation pressure)/(Pulse Pressure). Bland‐Altman analysis was performed. Mean difference (bias) ± one standard deviation of difference (with limits of agreement) of AIx between different devices was as follows: (a) Mobil‐O‐Graph vs Complior: −2.1 ± 14.8% (−31.1% to 26.9%), (b) Arteriograph vs Complior: 12.9 ± 14.6% (−15.7% to 41.5%), and (c) Mobil‐O‐Graph vs Arteriograph: −10.8 ± 16.9% (−43.9% to 22.3%). The three examined devices exerted significant differences in central AIx estimation which makes the three devices non‐interchangeable for wave reflection assessment. However, the Mobil‐O‐Graph device showed the highest agreement (lowest bias) with the Complior system as regards to the AIx measurement.

Progressive arterial stiffening, as a marker of arterial aging, may reach a plateau in elderly patients and may thus lose its clinical utility. This phenomenon may be more prominent in high-risk patients. We aimed to investigate if carotid-to-femoral pulse wave velocity (cf-PWV) is related to coronary artery disease (CAD) and diastolic dysfunction in elderly high-risk patients as compared to a control group of younger individuals.One-hundred and ninety-two high-risk stable patients who underwent coronary artery angiography and assessment of cf-PWV were consecutively recruited. Indices of diastolic dysfunction were also measured by echocardiography, including the volume of the left atrium and the ratio of early transmitral peak velocity (E) to the mitral annular early diastolic velocity (E').Increased cf-PWV was associated with the presence of CAD [odds ratio (OR) 1.34, P = 0.02], number of diseased coronary vessels (OR 1.17, P = 0.029) and CAD severity (P = 0.023) as assessed by Gensini score, in patients less than 65 years old after adjustment for traditional risk factors. Moreover, cf-PWV correlated with E/E' (P = 0.019) and increased the odds by 16% (OR 1.16, P = 0.048) for more severe diastolic dysfunction in patients aged below 65 years old. None of these outcomes correlated with cf-PWV in the elderly.In high cardiovascular risk patients, an age-dependent association of cf-PWV with CAD and diastolic dysfunction was evinced. In contrast to younger patients, these results suggest that measuring arterial stiffness in elderly high-risk patients may lack clinical value.

Background: The ancient Greek term "apoplexy" as is repeatedly mentioned by the Hippocratic School of Medicine, included a cluster of diseases, mainly those concerning the central nervous system. The term was wrongfully infiltrated in Western European medicine as synonymous to what is called today a "stroke" of the brain. Objective: While in "Corpus Hippocraticum" the definition of the stroke was rather ambiguous; our study aims to unveil those fragments referring to it, in order to compose the Hippocratic theory of what it stood for "Acute Brain Suffering" (Greek: Οξeίeς Οδύνeς του Eγκeφάλου) during the Classical era of ancient Greece. Method: A bibliographic research of the "Hippocratic Collection" was conducted during our study in order to connect all fragments from the original ancient Greek text, and reconstruct the "Hippocratic Stroke Theory". Three editions have been used as reference. French edition by Littre, and two Greek ones by Kaktos and Pournaropoulos. Results: The "Acute Brain Suffering" seems to be the entity we call "Stroke" in modern clinical practice. Edema (collection of fluids-humours theory) was considered to be the most significant element which though could have been addressed by a cranial decompression for the symptoms to improve. The symptoms in question were, acute brain pain, diplopia, vertigo, ataxia, saliva, and urine loss as well as feces incontinence. Conclusion: Both therapeutic approach and symptomatology exhibited significant similarities with the modern concept of the stroke. The Hippocratic School was a scientifically advanced sect of medicophilosophers who promoted global medicine.

Evidence regarding the influence of coffee on appetite and weight control is equivocal and the influence of covariates, such as genetic variation in caffeine metabolism, remains unknown. Herein, we addressed the novel hypothesis that genetic variation in CYP1A2, a gene responsible for more than 95% of caffeine metabolism, differentially impacts the association of coffee consumption with appetite and BMI among individuals with different genetic predispositions to obesity.A cross-over randomized intervention study involving 18 volunteers assessed the effects of coffee consumption on dietary intake, appetite, and levels of the appetite-controlling hormones asprosin and leptin. Data on habitual coffee intake, BMI, and perceived appetite were obtained from an observational cohort of 284 volunteers using validated questionnaires. Participants were stratified according to a validated genetic risk score (GRS) for obesity and to the -163C A (rs762551) polymorphism of CYP1A2 as rapid (AA), intermediate (AC), or slow (CC) caffeine metabolizers.Coffee consumption led to lower energy and dietary fat intake and circulating asprosin levels (P for interaction of rs762551 genotype*coffee consumption=0.056, 0.039, and 0.043, respectively) as compared to slow/intermediate metabolizers. High coffee consumption was more prevalent in rapid compared to slow metabolizers (P = 0.008 after adjustment for age, sex, and BMI) and was associated with lower appetite perception and lower BMI only in rapid metabolizers (P for interaction of rs762551 genotype*coffee consumption = 0.002 and 0.048, respectively). This differential association of rs762551 genotype and coffee consumption with BMI was more evident in individuals at higher genetic risk of obesity (mean adjusted difference in BMI = -5.82 kg/mCYP1A2 rs762551 polymorphism modifies the association of habitual coffee consumption with BMI, in part by influencing appetite, energy intake and circulating levels of the orexigenic hormone asprosin. This association is more evident in subjects with high genetic predisposition to obesity. ClinicalTrials.gov: registered Clinical Trial NCT04514588.

The impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during transcatheter aortic valve implantation (TAVI) are unknown. Our aim was to evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events in patients undergoing TAVI. Patients scheduled for TAVI were randomized previous to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 reaction units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions. Among 90 patients randomized, 6 had an inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, hypertension, aortic valve calcium content, procedural ACT, and pre-implantation balloon valvuloplasty, patients on ticagrelor had on average 256.8 (95% CI: [-335.7, -176.5]) fewer total procedural HITS than patients on clopidogrel. Platelet inhibition was greater with ticagrelor 26 [10, 74.5] PRU than with clopidogrel 207.5 (120 to 236.2) PRU, p0.001, and correlated significantly with procedural HITS (r = 0.5, p0.05). In conclusion, ticagrelor resulted in fewer procedural HITS, compared with clopidogrel, in patients undergoing TAVI, while achieving greater platelet inhibition.

COVID-19 pandemic has undoubtedly disrupted the well-established, traditional structure of medical education. Τhe new limitations of physical presence have accelerated the development of an online learning environment, comprising both of asynchronous and synchronous distance education, and the introduction of novel ways of student assessment. At the same time, this prolonged crisis had serious implications on the lives of medical students including their psychological well-being and the impact on their academic trajectories. The new reality has, on many occasions, triggered the ‘acting up’ of medical students as frontline healthcare staff, which has been perceived by many of them as a positive learning and contributing experience, and has led to a variety of responses from the educational institutions. All things considered, the urgency for rapid and novel adaptations to the new circumstances has functioned as a springboard for remarkable innovations in medical education,including the promotion of a more “evidence-based” approach.

ObjectivesTo evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events, in patients undergoing transcatheter aortic valve replacement (TAVR).BackgroundThe impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during TAVR are unknown.MethodsPatients scheduled for TAVR were randomized prior to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 Reaction Units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions.ResultsAmong 90 patients randomized, six had inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p< 0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, and aortic valve calcium content, patients on ticagrelor had on average 255.9 (95% CI: [-335.4, -176.4]) fewer total procedural HITS, than did patients on clopidogrel. Platelet inhibition was greater in those randomized to ticagrelor 26 [10, 74.5] PRU than in those randomized to clopidogrel 207.5 [120-236.2] PRU, pConclusionsTicagrelor resulted in fewer procedural HITS, compared to clopidogrel, in patients undergoing TAVR, while achieving greater platelet inhibition, without increasing the risk for complications.Clinical Trial(ClinicalTrials.gov Identifier: NCT02989558)CONDENSED ABSTRACTWe conducted a two-center, prospective, open label, randomized, controlled clinical trial to compare the efficacy of ticagrelor vs clopidogrel in preventing cerebrovascular embolic events as assessed by transcranial Doppler during TAVR.The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) than in the clopidogrel group (723.5 [471.5, 875.0]), p< 0.001. Patients on ticagrelor had on average 255.9 (95% CI: [-335.4, -176.4]) fewer total procedural HITS than those on clopidogrel. This protective effect was not associated with an increase in complications.

Cardiac and aortic characteristics are crucial for cardiovascular disease detection. However, noninvasive estimation of aortic hemodynamics and cardiac contractility is still challenging. This paper investigated the potential of estimating aortic systolic pressure (aSBP), cardiac output (CO), and end-systolic elastance (Ees) from cuff-pressure and pulse wave velocity (PWV) using regression analysis. The importance of incorporating ejection fraction (EF) as additional input for estimating Ees was also assessed. The models, including Random Forest, Support Vector Regressor, Ridge, Gradient Boosting, were trained/validated using synthetic data (n = 4,018) from an in-silico model. When cuff-pressure and PWV were used as inputs, the normalized-RMSEs/correlations for aSBP, CO, and Ees (best-performing models) were 3.36 ± 0.74%/0.99, 7.60 ± 0.68%/0.96, and 16.96 ± 0.64%/0.37, respectively. Using EF as additional input for estimating Ees significantly improved the predictions (7.00 ± 0.78%/0.92). Results showed that the use of noninvasive pressure measurements allows estimating aSBP and CO with acceptable accuracy. In contrast, Ees cannot be predicted from pressure signals alone. Addition of the EF information greatly improves the estimated Ees. Accuracy of the model-derived aSBP compared to in-vivo aSBP (n = 783) was very satisfactory (5.26 ± 2.30%/0.97). Future in-vivo evaluation of CO and Ees estimations remains to be conducted. This novel methodology has potential to improve the noninvasive monitoring of aortic hemodynamics and cardiac contractility.

Background The traditional technique of gastrointestinal reconstruction of the esophagus after esophagectomy presents plenty of complications. Hence, tissue engineering has been introduced as an effective artificial alternative with potentially fewer complications. Three types of esophageal scaffolds have been used in experimental studies so far. The aim of our meta-analysis is to present the postoperative outcomes after esophageal replacement with artificial scaffolds and the investigation of possible factors that affect these outcomes. Methods The present proportional meta-analysis was designed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and A MeaSurement Tool to Assess systematic Reviews guidelines. We searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL, and Google Scholar databases from inception until February 2020. Results Overall, 32 studies were included that recruited 587 animals. The pooled morbidity after esophageal scaffold implantation was 53.4% (95% CI = 36.6–70.0%). The pooled survival interval was 111.1 days (95% CI = 65.5–156.8 days). Graft stenosis (46%), postoperative dysphagia (15%), and anastomotic leak (12%) were the most common complications after esophageal scaffold implantation. Animals that underwent an implantation of an artificial scaffold in the thoracic part of their esophagus presented higher survival rates than animals that underwent scaffold implantation in the cervical or abdominal part of their esophagus (P Conclusion Tissue engineering seems to offer an effective alternative for the repair of esophageal defects in animal models. Nevertheless, issues like graft stenosis and lack of motility of the esophageal scaffolds need to be addressed in future experimental studies before scaffolds can be tested in human trials.

Introduction: Many studies have shown that electrostimulation of the cavernosal nerve can induce and maintain penile erection. Based on these discoveries, neurostimulation to activate the erectile response has been considered a potential solution to treat erectile dysfunction (ED). However, despite recognized potential, this technology has not been further developed. The barrier is the complex anatomy of the human cavernous nerve, which challenges the intraoperative identification of the cavernosal nerves for electrode placement., Aim: To overcome this major barrier, we proposed a practical solution: a 2-dimensional flexible electrode array that can cover the entire plexus area, ensuring that at least 1 of the electrodes will be in optimal contact with the cavernosal nerve, without the need of intraoperative identification. The present study aims to evaluate this concept intraoperatively., Methods: 24 patients enrolled for open radical prostatectomy were recruited. During the surgical procedures, the electrode array was positioned on the pelvic plexus (on the prostatic apex or pelvic wall) and electrical stimulation was applied to induce penile erection. Penile erectile response was assessed by (i) visual change of penile tumescence and (ii) by a penile plethysmograph system., Main Outcome Measure: Ability and success rate of evoking penile response were measured by applying electrical stimulation using the developed electrode array., Results: Electrical stimulation produced immediate penile response in all cases when tested before (on prostatic apex) or after prostate removal (on pelvic wall). Clear visual penile engorgement was observed in 75% of the cases, whereas 25% showed minimal to moderate penile tumescence. As expected, patients with lower International Index of Erectile Function-5 score presented a reduced response, whereas stimulation before prostate removal showed greater response than following removal. Interestingly, erectile response was potentiated by bilateral stimulation (circumference increase [mm]: 2.7 +/- 1.02 vs. 8.2 +/- 1.9, P=.01)., Clinical Implications: These data bring sufficient proof of concept of a conceivable novel medical implant for the treatment of ED caused by mechanical nerve injury, such as prostatectomy and spinal cord injury., Strength & Limitations: This is the first approach that can ensure the optimal site stimulation of the erectogenic neuronal path within the lower pelvic area and overcome the major barrier of individual anatomic variability. However, because this study was performed intraoperatively in an acute scenario, further studies are needed to evaluate its chronic efficacy for clinical practice., Conclusion: The flexible electrode array concept can ensure the electrostimulation of erectogenic neuronal path when positioned on the prostate apex or pelvic floor. Copyright (C) 2018, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

BACKGROUND There is increasing evidence that the method of calibration directly influences the association between brachial systolic blood pressure (bSBP) and estimated aortic systolic blood pressure (aSBP) and subsequently affects prognostic and diagnostic differentiation power of the latter. OBJECTIVE The aim of this study was to investigate associations between different methods of systolic pressure assessment in a large cohort and its comparison with recently published evidence. PARTICIPANTS AND METHODS During a public health campaign, cardiovascular hemodynamic data were assessed using a validated oscillometric device in a pharmacy setting. The device measures bSBP, mean arterial pressure, and diastolic blood pressure (DBP), and records brachial waveforms at the DBP level. aSBP1 was derived using bSBP and DBP and aSBP2 using measured mean arterial pressure and DBP for waveform calibration. In addition to pressures, age, sex, and anthropometric data were recorded. Regression analysis was carried out to investigate associations. RESULTS A total of 7409 (5133/2276, female/male) individuals with a median age of 54 years were sampled. aSBPs differed significantly from bSBP (126.0 mmHg) for aSBP1 (117.0 mmHg) and aSBP2 (127.5 mmHg, both P

This study used a questionnaire to examine how academic staff members in Greece and Cyprus feel about the changes in undergraduate medical education during the COVID-19 pandemic. In general, e-learning was not considered an adequate way of teaching and was less enjoyable. Participants aged 31-40 years experienced more ( P = .001), while staff in higher academic ranks less difficulty ( P 6 h was increased from 28.8% to 57.5%. The majority (74.2%) stated that scientific and educational training opportunities were not affected by the pandemic. In conclusion, the pandemic has induced important changes in undergraduate medical education. This new condition was considered adequate but not pleasant, with younger faculty members being more burdened.