Drop In Systolic Pressure Research Articles

Virtual Planning and Patient-Specific Graft Design for Aortic Repairs.

Patients presenting with coarctation of the aorta (CoA) may also suffer from co-existing transverse arch hypoplasia (TAH). Depending on the risks associated with the surgery and the severity of TAH, clinicians may decide to repair only CoA, and monitor the TAH to see if it improves as the patient grows. While acutely successful, eventually hemodynamics may become suboptimal if TAH is left untreated. The objective of this work aims to develop a patient-specific surgical planning framework for predicting and assessing postoperative outcomes of simple CoA repair and comprehensive repair of CoA and TAH. The surgical planning framework consisted of virtual clamp placement, stenosis resection, and design and optimization of patient-specific aortic grafts that involved geometrical modeling of the graft and computational fluid dynamics (CFD) simulation for evaluating various surgical plans. Time-dependent CFD simulations were performed using Windkessel boundary conditions at the outlets that were obtained from patient-specific non-invasive pressure and flow data to predict hemodynamics before and after the virtual repairs. We applied the proposed framework to investigate optimal repairs for six patients (n = 6) diagnosed with both CoA and TAH. Design optimization was performed by creating a combination of a tubular graft and a waterslide patch to reconstruct the aortic arch. The surfaces of the designed graft were parameterized to optimize the shape. Peak systolic pressure drop (PSPD) and time-averaged wall shear stress (TAWSS) were used as performance metrics to evaluate surgical outcomes of various graft designs and implantation. The average PSPD improvements were 28% and 44% after the isolated CoA repair and comprehensive repair, respectively. Maximum values of TAWSS were decreased by 60% after CoA repair and further improved by 22% after the comprehensive repair. The oscillatory shear index was calculated and the values were confirmed to be in the normal range after the repairs. The results showed that the comprehensive repair outperforms the simple CoA repair and may be more advantageous in the long term in some patients. We demonstrated that the surgical planning and patient-specific flow simulations could potentially affect the selection and outcomes of aorta repairs.

Catheter-directed therapies impact on intermediate-high- and high-risk pulmonary embolism patients

Abstract Introduction Intermediate-high- and high-risk pulmonary embolism (PE) patients treated with anticoagulation alone are associated with a considerable risk of circulatory collapse, death, or long-term pulmonary hypertension. Pulmonary Embolism Response Teams (PERT) have been created to deliver PE patients a better care. Catheter Directed Therapies (CDT), with mechanical thrombolysis and/or local fibrinolysis allow faster reperfusion and hemodynamic improvement without the systemic hemorrhagic effects of systemic fibrinolysis. The clinical evidence of its benefits is lacking. Objectives This analysis aims to describe the hemodynamics, morphological and perfusion improvement in intermediate-high- and high-risk acute PE patients submitted to CDT. Methods Prospective registry of consecutive intermediate-high- and high-risk PE patients submitted to CDT (mechanical thrombolysis with PenumbraÔ aspiration system and/or intrapulmonary local fibrinolysis with alteplase) in a single tertiary center. A multiparametric follow-up protocol was designed to evaluate echocardiographic, CT-scan, pulmonary angiogram, and right heart catheterization data at admission and at 3 months after CDT. The paired samples t-Test was used for the analysis of the variables. Results 26 PE patients (42.3% male, mean age 59 years old) were submitted to CDT (19% combined Penumbra and local fibrinolysis, 12% isolated Penumbra and 69% isolated local fibrinolysis). Baseline characteristics, laboratorial, imaging and procedure data are summarized in the figure 1. No major bleeding was seen during or after the procedure. 1 pulmonary artery dissection and 1 Penumbra burr partial avulsion occurred, both with conservative treatment with good result. 3 patients died during the follow-up (1 for oncologic disease, 1 for septic shock and 1 after discharge with undetermined cause). Of the remaining, 18 patients completed the 3-month follow-up protocol. At 3 months, a significant improvement was seen in the patients’ hemodynamics with 3.3mmHg mean drop of RA pressure (p 0.007), 16.1mmHg mean drop of systolic PA pressure (p <0.001), 8.0mmHg mean drop of mean PA pressure (p<0.001), 1.4L/min and 0.7L/min/m2 mean increases in cardiac output and index (p 0.003, p 0.001), and a tendency to a 0.8 Wood units decrease in the pulmonary vascular resistance (p 0.093). It was also seen an improvement in the perfusion defects with a mean drop of 7.9 points in the modified Miller index (p <0.001) and an improvement in the RV function with a mean decrease of 0.5 in the RV/LV ratio by CT-scan (p <0.001), a mean increase of 5.6mm in TAPSE (p <0.001) and a decrease of median NT-proBNP levels in 2866pg/ml (p <0.001). Conclusions In patients with intermediate-high- and high-risk PE, the use of CDT with mechanical thrombolysis and/or local fibrinolysis is safe and associated with improvement in hemodynamics, RV function and perfusion defects.Table 1.baseline characteristicsTable 2.results

Acute Fasting Decreases Tolerance to Lower Body Negative Pressure

Potential health benefits of an acute fast include reductions in blood pressure and increases in vagal cardiac control. These purported health benefits could put fasted humans at risk for cardiovascular collapse when exposed to central hypovolemia. Intense lower body negative pressure (LBNP) induces reproducible and reversible central hypovolemia. The purpose of this study was to investigate the influence of an acute 24‐hour fast on tolerance to severe LBNP. We tested the hypothesis that fasting would reduce tolerance to severe LBNP. Ours was a randomized, crossover design with an LBNP tolerance test occurring 3‐hrs postprandial (fed) and 24‐hrs postprandial (fast). A standardized meal was provided for both conditions. Criteria for termination of LBNP was; 1) a drop in systolic pressure of 15 mmHg or greater for 10 s and/or 2) sudden bradycardia. Eighteen young (23±0.7 yrs), normotensive, non‐obese (25±0.8 BMI), participants were brought to presyncope. We measured blood glucose (GLU), ketones (β‐OHB), and triglycerides (TRG) to confirm a successful fast. With subjects in a supine position, we recorded the ECG, beat‐to‐beat arterial pressure (finger plethysmography), muscle sympathetic nerve activity (MSNA; N=7), and forearm blood flow via venous occlusion plethysmography (VOP; N=12). Following a 5‐min baseline, LBNP was increased in 15 mmHg increments every 5 min in a stepwise manner until onset of presyncope. LBNP levels eliciting presyncope were denoted as 100% tolerance, data were assessed relative to this normalized maximal tolerance by expressing LBNP as 80, 40, and 0% (baseline) of maximal tolerance. Data are expressed as means ± SE. P‐values ≤ 0.05 were considered statistically significant and indicated by an (*). Changes in TRG, GLU and β‐OHB with fasting were consistent with expectations: TRG and GLU decreased (TRG; 130±16 fed vs. 78±9* mg/dL fast) (GLU; 100±3 fed vs. 81±2* mg/dL fast), and β‐OHB increased (β‐OHB; 0.12±.04 fed vs. 0.47±.11* mmol/L fast). Our participants were similarly hydrated, measured via urine specific gravity, (1.0168±.002 fed vs. 1.0122±.003 a.u. fast) and weight stable (77.8±3.6 fed vs. 76.9±3.4 kg fast) between conditions. Tolerance to central hypovolemia was decreased by ~10% in the fasted condition measured via total duration of negative pressure (1370±89 fed vs. 1229±94* s fast). At each normalized time point, heart rate and MSNA increased similarly in both conditions. Additionally, systolic blood pressure and stroke volume decreased similarly in both conditions. Both forearm blood flow (FBF) and forearm vascular resistance (FVR) are expressed as a percent change from 0 to 100%. ΔFBF significantly decreased in the fed condition at 100% (‐45.8±4.8 fed vs. ‐23.5±8.1* % fast) and ΔFVR increased in the fed condition at 100% (141.6±34.5 fed vs. 67.1±24.8* % fast). Our results suggest that acute fasting reduces tolerance to central hypovolemia by blunting increases in peripheral vascular resistance, and could lead to earlier decompensation when compared to the normal, fed state.

Abstract 12259: Early Mechanical Signs of Myocardial Injury in a Model of Systemic Inflammation

Introduction: Early detection of myocardial dysfunction in severe inflammations, as myocarditis COVID-19 and sepsis, is of great merit. We hypothesized that metalloproteinases (MMPs) discharge from activated macrophages and leukocytes dismantles the extracellular matrix (ECM), leading to diastolic and systolic dysfunctions. Methods: The right and left ventricle functions were studies in a unique Langendorff setup, with computer controlled preloads and afterloads, utilizing rat hearts (n=7). Collagenase (MMP8) was added to the Krebs-Henseleit solution after the baseline recording. Pressure-Area loops and changes in the cardiac geometry were continuously recorded by short-axis ultrasound cines (15MHz, 20 fps) of both ventricles. Results: ECM dismantling caused immediate systolic and diastolic dysfunctions, especially in the LV. Significant decreases in the LV systolic pressure and EDV developed with overt shift of the end-diastolic pressure-volume relationship toward lower volumes. The decrease in the EDV was associated with myocardial wall thickening. After collagenase perfusion yielded 10% drop in systolic pressure, LV EDV at EDP of 12 mmHg dropped by 20.0±17.2 % (p=0.04) and LV wall volume increased by 3.39±3.68 % (p=0.04), without significant changes in the epicardial diameter. Consequently, both diastolic stiffness to volume ratio (S2V) of the diastolic elastance to EDV, and myocardial wall thickness to cavity area ratio (W2C) significantly increased. S2V and W2C increased by 1.48±0.51 and 1.32±0.34 folds relative to baseline, respectively (p=0.03, p =0.03). S2V and W2C increased by 1.82±0.71 and 1.52±0.46 folds, respectively, after 20% drop in systolic pressure (p= 0.02, p=0.02). An intact ECM is essential for the diastolic recoil. Dismantling the ECM diminishes the diastolic recoil and increases diastolic stiffness. Interestingly, the right ventricle presented similar trends, but the changes were insignificant, and the RV was less vulnerable to damage. Conclusion: ECM degradation causes severe systolic and diastolic dysfunctions. Novel indices (S2V and W2C) for early detection of myocardial involvement in severe inflammatory diseases were developed.

Effect of Sildenafil on Mortality in Term Neonates with Hypoxemic Respiratory Failure due to Persistent Pulmonary Hypertension (SIPHON) - A Randomised Control Trial

Introduction: Persistent Pulmonary Hypertension (PPHN) complicates the transition from intrauterine to extrauterine life in some neonates. Sildenafil is known to reduce pulmonary pressures. However, its effect on reducing mortality is unclear. This study is conducted to determine the effect of Sildenafil in reducing all-cause mortality rate in term newborns with hypoxemic respiratory failure due to pulmonary hypertension. Methods: This was a double-blinded randomised control trial done in a level 3 neonatal intensive care unit. Term neonates on mechanical ventilation with an Oxygenation Index (OI) > 15, and echocardiography suggesting PPHN were included in the study. The drug group received intravenous Sildenafil and the placebo group normal saline. The difference in the mortality rate between the two groups was analysed. Results: Eleven babies were randomised to the drug group and 12 to the placebo group. Both the groups matched in terms of their baseline characteristics. The difference in the drop of OI and right ventricular systolic pressure (RVSP) between the drug and placebo groups was not statistically significant. The relative risk of mortality was 0.436 in the intervention group (95% CI 0.105 to 1.80). The difference in the mortality rate was not statistically significant with P- value of 0.252. The rate of complications such as necrotising enterocolitis, sepsis, and pneumothorax was not different between the two groups. Conclusions: Intravenous sildenafil does not have any significant benefit over placebo in reducing all-cause mortality, oxygenation index, RVSP or complications when compared to placebo.

Efficacy and safety of local intracoronary drug delivery in the distal coronary bed as treatment of no-reflow phenomenon during percutaneous coronary intervention

Abstract Background No-reflow is a complication of percutaneous coronary interventions (PCI), which occurs in 0.6–5% of elective PCIs, but it may be observed in up to 50% of primary PCI cases, involving the treatment of thrombus-containing lesions. An optimal standard treatment of no-reflow (NR) has not yet been established. Intracoronary (IC) vasodilators are being administered for the treatment of NR via the guiding catheter, but sometimes distal flow restoration is not satisfactory especially in patients with TIMI 0 flow. Purpose To investigate the efficacy and safety of local IC drug delivery in the distal coronary bed via a microcatheter as a treatment option of NR phenomenon during PCI. Methods A retrospective analysis of 4606 PCI procedures done in our institution was conducted, to identify patients who suffered from NR during PCI (TIMI 0-I flow in the absence of mechanical obstruction). In patients with NR, local IC infusion of vasodilators (Nitroprusside 50–200 mcg, Adenosine 30–40 mcg) was infused, via a microcatheter or thrombus-aspiration catheter, distal to the angioplasty site. Repeated injections were done with both drugs at the operator's discretion, until best flow was achieved, but without exceeding the maximum recommended dose. If the patient was hypotensive and, thus, the administration of IC vasodilators for treating slow flow/NR was impeded, 100–200 mcg IV phenylephrine were administered, to increase blood pressure. Afterwards, IC vasodilators were infused. Results In 4606 conducted PCIs, 83 patients suffered from NR (1.8%). The age of patients with NR was 65.17±11.69 years. As for the sex, there were 10 female (12.1%) and 73 male (87.9%) patients. The mode of presentation was: 1) STEMI in 28 patients (33.7%), 2) NSTEMI-Unstable Angina in 21 patients (25.3%) and 3) stable angina in 34 patients (41%). NR was observed in 57 patients (68.7%) at post-stenting and in 26 patients (31,3%) at post-dilation. The affected vessel was LAD in 35 patients (42.2%), LCx artery in 16 patients (19.3%), RCA in 28 patients (33.7%) and SVG in 4 patients (4.8%). The IC-infused drug was adenosine in 21 patients and nitroprusside in 62 patients. The total number of infusions was 4.05±1.88. TIMI III flow was achieved in 90.3% of patients and MBG II/III was achieved in 89.1%. The combination of TIMI III flow with MBG II/III was achieved in 87.9% of the patients. In the subgroup of patients with STEMI, the combination of TIMI III flow with MBG II/III was achieved in 85,7% of the patients. As for the complications, a transient systolic pressure drop below 90 mmHg occurred in 4 patients, while there was one death, due to cardiogenic shock complicating acute anterior MI. Conclusion Local IC delivery of vasodilator drugs in the distal coronary bed via microcatheter during PCI is a safe and effective treatment of NR phenomenon, and it can enhance the myocardial perfusion, in addition to reducing infarct's size. Also, it may improve the post-PCI prognosis. Funding Acknowledgement Type of funding sources: None.

Influence of Standardized Nursing Management of Hospital Based on Smart Electronic Medical Blockchain on Nursing Quality of Digestive Endoscopy Room.

With the increase of the incidence rate of digestive system diseases, digestive endoscopy has become an essential measure. The nursing quality of digestive endoscopy room will have a direct impact on the examination results and treatment effect, so improving the nursing quality of digestive endoscopy room has always been the focus of attention. In this paper, the smart electronic medical blockchain technology and hospital standardized nursing management mode are combined to develop the smart medical standardized nursing management mode. Firstly, 88 patients with digestive endoscopy in a hospital from October 2018 to October 2019 were selected as the experimental subjects: 44 cases in the control group and 44 cases in the experimental group. The control group implemented the traditional management mode of digestive endoscopy room, and the experimental group implemented the standardized nursing management mode of smart medicine. The blood pressure level before and after nursing and the probability of adverse reactions in the process of nursing were counted. After nursing, the patients were asked to fill in the nursing satisfaction questionnaire, evaluate the nursing quality of nursing staff, and make statistics and comparison on the occurrence of safety events in digestive endoscopy room. After nursing, the systolic pressure drop of the experimental group was 125.36 ± 7.27 mmhg, diastolic pressure drop was 73.24 ± 4.21 mmhg, and the incidence of adverse reactions was 11.36%. The satisfaction rate of the experimental group was 15%, 29.55%, and 22.73% higher than that of the control group. The average scores of nursing skills, operation level, and examination results of nursing staff in the experimental group were 94.49, 95.12, and 95.89, respectively; the qualified rate of disinfection of digestive endoscopy room in the experimental group was 100%, the degree of cooperation between doctors and nurses was 100%, the timely rate of emergency measures was 95.45%, and the incidence of accidents was 0%. This shows that, under the standardized nursing of smart medicine, the blood pressure of patients is more stable, the incidence of adverse reactions is lower, the nursing satisfaction is higher, and the nursing quality of nursing staff and the safety of digestive endoscopy room are also improved.

Biologically-engineered Pediatric Tri-tube Valved Conduit Evaluated 52 Weeks in the Growing Lamb

Objective: There is a dire need for a heart valve that can grow with children. We fabricated tubes of biologically-engineered matrix that have been shown to regenerate and grow as a pulmonary artery replacement in lambs, and implemented a novel design for a valved conduit made from sewing three of these tubes together with degradable suture that confers valve growth potential. The study was to assess valve function and growth potential over a one-year period in the lamb model. Methods: Seven lambs were implanted with tri-tube valved conduits in sequential cohorts and compared to bioprosthetic conduits using longitudinal echocardiography and histological and mechanical characterization post-explantation. Results: Valves implanted in two lambs of the first cohort of four animals functioned with only mild regurgitation and systolic pressure drops <10 mmHg up to 52 weeks post-implantation, during which the valve diameter increased from 19 mm to a normal ~25 mm. In a second cohort of three animals, an additional tube was used to create a sleeve around the tri-tube valve to counteract faster root growth relative to the leaflets. Two valves exhibited only trivial-to-mild regurgitation at 52-weeks with similar diameter increase and systolic pressure drops of < 5 mm Hg. The same was true for the third animal until moderate regurgitation at 52 weeks correlating to hyper-increase of the valve diameter. In all explanted valves, the leaflets remained thin and pliable with only sparse, punctate microcalcification at most, and they contained interstitial cells and an endothelium progressing from the base of the leaflets. Conclusions: These results are demonstrably improved in terms of calcification and hemodynamic function compared to reported studies for clinically-used pediatric bioprosthetic valves tested in the same model. The results demonstrate the potential for long-term valve growth of this “off-the-shelf” tri-tube valved conduit in children.

Changes in Noninvasive Arterial Stiffness and Central Blood Pressure After Endovascular Abdominal Aneurysm Repair

Purpose: To evaluate the impact of elective endovascular aneurysm repair (EVAR) on the carotid-femoral pulse wave velocity (cfPWV) and central pressure waveform, through 1-year follow-up. Materials and Methods: A tonometric device was used to measure cfPWV and estimate the central pressure waveform in 20 patients with an infrarenal abdominal aortic aneurysm scheduled for elective EVAR. The evaluated central hemodynamic parameters included the central pressures, the augmentation index (AIx), and the subendocardial viability ratio (SEVR). AIx quantifies the contribution of reflected wave to the central systolic pressure, whereas SEVR describes the myocardial perfusion relative to the cardiac workload. Measurements were performed before EVAR, at discharge, and 6 weeks and 1 year after EVAR. Results: CfPWV was increased at discharge (12.4±0.4 vs 11.3±0.5 m/s at baseline; p=0.005) and remained elevated over the course of 1-year follow-up (6 weeks: cfPWV = 12.2±0.5 m/s; 1 year: cfPWV = 12.2±0.7 m/s, p<0.05). After an initial drop in systolic central pressure at discharge, all the central pressures increased thereafter up to 1 year, without significant differences compared with baseline. The same was observed for the AIx and SEVR. Conclusion: Endovascular aortic aneurysm repair caused an increase in pulse wave velocity compared with baseline, which remained elevated through 1 year follow-up, which may be related to an increased cardiovascular risk. However, no differences in central pressure, augmentation index, and subendocardial viability ration were observed during follow-up.

Pediatric tri-tube valved conduits made from fibroblast-produced extracellular matrix evaluated over 52 weeks in growing lambs.

There is a need for replacement heart valves that can grow with children. We fabricated tubes of fibroblast-derived collagenous matrix that have been shown to regenerate and grow as a pulmonary artery replacement in lambs and implemented a design for a valved conduit consisting of three tubes sewn together. Seven lambs were implanted with tri-tube valved conduits in sequential cohorts and compared to bioprosthetic conduits. Valves implanted into the pulmonary artery of two lambs of the first cohort of four animals functioned with mild regurgitation and systolic pressure drops <10 mmHg up to 52 weeks after implantation, during which the valve diameter increased from 19 mm to a physiologically normal ~25 mm. In a second cohort, the valve design was modified to include an additional tube, creating a sleeve around the tri-tube valve to counteract faster root growth relative to the leaflets. Two valves exhibited trivial-to-mild regurgitation at 52 weeks with similar diameter increases to ~25 mm and systolic pressure drops of <5 mmHg, whereas the third valve showed similar findings until moderate regurgitation was observed at 52 weeks, correlating to hyperincrease in the valve diameter. In all explanted valves, the leaflets contained interstitial cells and an endothelium progressing from the base of the leaflets and remained thin and pliable with sparse, punctate microcalcifications. The tri-tube valves demonstrated reduced calcification and improved hemodynamic function compared to clinically used pediatric bioprosthetic valves tested in the same model. This tri-tube valved conduit has potential for long-term valve growth in children.

Electrical Cardiometry and Cardiac Biomarkers in 24-h and 48-h Ultramarathoners

Our study aimed to (i) utilize novel electrical cardiometry and observe acute changes in cardiac biomarkers among 24-h and 48-h ultra-marathoners, and (ii) examine whether alterations in cardiac responses were associated with the average running speed of these participants. Twenty-four 24-h and sixteen 48-h ultra-marathoners were recruited. Electrical cardiometry in the 2 groups showed significant post-race drops in systolic pressure (24-h: p=0.001; 48-h: p=0.016) and rapid increases in heart rate (24-h, p=0.004; 48-h, p=0.001). Cardiac output increased in 48-h runners (p=0.012) and stroke volume decreased in 24-h runners (p=0.009) at post-test. Six of 20 (30%) 24-h and 4 of 16 (25%) 48-h runners had high-sensitivity troponin T values above the reference interval after the races. N-terminal proB-type natriuretic peptide levels showed a 15-fold increase in 24-h runners and a 10-fold increase in 48-h runners at post-race. There was a positive correlation between delta N-terminal proB-type natriuretic peptide and running mileage (rs=0.629, p=0.003) in 24-h ultra-marathoners. In conclusion, stroke volume and cardiac output showed inconsistent changes between the 2 groups. Average running speed has a significant effect on post-exercise elevation in cardiac biomarkers.

The transverse diameter of right common femoral vein by ultrasound in the supine position for predicting post-spinal hypotension during cesarean delivery

BackgroundPost-spinal anesthesia hypotension during cesarean delivery is caused by decreased systemic vascular resistance due to the blockage of the autonomic nerves, which is further worsened by inferior vena cava (IVC) compression by the gravid uterus. This study aimed to assess whether peak velocity and diameter of the IVC below the xiphoid or right common femoral vein (RCFV) in the inguinal region, as measured on ultrasound, could reflect the degree of IVC compression and further identify parturients at risk of post-spinal hypotension.MethodsFifty-six parturients who underwent elective cesarean section with spinal anesthesia were included in this study; peak velocities and anteroposterior diameters of the IVC and peak velocities and transverse diameters of the RCFV were measured using ultrasound before anesthesia. The primary outcome was the ultrasound measurements of IVC and RCFV acquired before spinal anesthesia and their association with post-spinal hypotension. Hypotension was defined as a drop in systolic arterial pressure by > 20% from the baseline. Multinomial logistic regression analysis was used to identify the association between the measurements of IVC, RCFV, and post-spinal hypotension during cesarean delivery. Receiver operating characteristic curves were used to test the abilities of the identified parameters to predict post-spinal hypotension; the areas under the curve and optimum cut-off values for the predictive parameters were calculated.ResultsA longer transverse diameter of the RCFV was associated with the occurrence of post-spinal hypotension (odds ratio = 2.022, 95% confidence interval [CI] 1.261–3.243). The area under the receiver operating characteristics curve for the prediction of post-spinal hypotension was 0.759 (95% CI 0.628–0.890, P = 0.001). A transverse diameter of > 12.2 mm of the RCFV could predict post-spinal hypotension during cesarean delivery.ConclusionsA longer transverse diameter of RCFV was associated with hypotension and could predict parturients at a major risk of hypotension before anesthesia.Trial registrationThis study was registered at http://www.chictr.org.cn on 16, May, 2018. No. ChiCTR1800016163.

Syncope in Acute Pulmonary Embolism. Importance of Early Recognition of Recurrent Syncope as a Manifestation of Acute Bilateral Pulmonary Embolism

A 43-year-old female patient with past medical history of superficial DVTs, nicotine dependency, and morbid obesity presented with shortness of breath and syncope. She was found to be tachycardic with elevated D-Dimer. Emergent chest-CT was performed which revealed large bilateral pulmonary emboli. As her vitals were within normal limits at that time, there were no indications for tissue plasminogen activator. Later, patient started having fleeting episodes of bradycardia and hypotension with drop in systolic pressure over 40mmHg on slight movements. Being in a rural hospital with limited resources, the decision was made to transfer the patient. Following the transfer, the patient was pronounced deceased due to complications related to her condition. We report this case to emphasize the importance of early recognition and management with thrombolytic therapy or mechanical thrombectomy if contraindications exist in patients with recurrent syncope in a rural setting.

A preoperative modified Allen test result may be associated with long term mortality after hemodialysis access construction.

The modified Allen test (MAT) is a simple bedside method determining collateral hand circulation prior to hemodialysis (HD) access surgery. Hand ischemia as reflected by low systolic finger pressures (Pdig) is associated with high mortality rates in severe kidney disease (CKD) patients. Aim of the present study was to assess a possible relation between absolute finger pressure drop (∂Pdig) during a preoperative MAT and mortality after a first HD access construction. Pdig (systolic pressure, mmHg) was measured using digital plethysmography following compression of radial and ulnar arteries in CKD patients just before access surgery between January 2009 and December 2018 in one center. The greatest ∂Pdig of both index fingers was used for analysis. Cardiovascular and overall mortality were assessed during the following 4 years using the ERA-EDTA classification system (codes 11, 14-16, 18, 22-26, 29). Cox regression analysis determined possible associations between ∂Pdig and mortality. Complete data sets were available in 108 patients (male n = 71; age 70 years ±12; mean follow up (FU) 1.6 years ±0.1; FU index 99% ±1). Median ∂Pdig was 31 mmHg (range 0-167 mmHg). Patients having cardiovascular disease (CV+) demonstrated higher ∂Pdig values (CV+ 44 ± 5 mmHg vs CV- 29 ± 3 mmHg, p = 0.012). A total of 26 patients (24%) died during FU (CV+ death, n = 16; 62%). For each 10 mmHg ∂Pdig increase, overall mortality increased by 10%, and CV+ mortality by 15% (overall mortality: HR 1.10 [1.01-1.22], p = 0.048; CV+ mortality: 1.15 [1.03-1.29], p = 0.017). Following correction for age, ∂Pdig remained associated with CV+ mortality (HR 1.13 [1.00-1.26], p = 0.043). A large drop in systolic finger pressure during a preoperative MAT is related to mortality after primary HD access surgery. The role of this potential novel risk parameter requires confirmation in a larger population.

Prevalence of triceps suralis lenghtening among crouch gait in cerebral palsy

Aortic interleaflet triangle reshaping (AITR) is a surgical approach to aortic valve incontinence that involves placing three stitches at half of the interleaflet triangles height. In this work, the relationship between the actual stitch height and valve functioning, and the safety margin that the surgeon can rely on in applying the stitches were systematically investigated in vitro. AITR surgery was applied to six swine aortic roots placing the stitches empirically at 50%, 60% and 75% of the triangle heights. Then the actual stitch heights were measured and the hydrodynamic performances were evaluated with a pulsatile hydrodynamic mock loop. Actual stitch heights were 45±2%, 61±4% and 79±6%. As compared to untreated conditions, the 50% configuration induced a significant variation in the effective orifice area. With stitches placed at 60%, the mean systolic pressure drop increased significantly with respect to the untreated case, but no significant changes were recorded with respect to the 50% configuration. At 75%, all the hydrodynamic parameters of systolic valve functioning worsened significantly. Summarizing, the AITR technique, when performed in a conservative manner did not induce significant alterations in the hydrodynamics of the aortic root in vitro, while more aggressive configurations did. The absence of a statistically significant difference between the 50% and 60% configurations suggests that there is a reasonably limited risk of inducing valve stenosis in the post-op scenario due to stitch misplacement.

Non-invasive Prediction of Peak Systolic Pressure Drop across Coarctation of Aorta using Computational Fluid Dynamics.

This paper proposes a novel method to noninvasively measure the peak systolic pressure difference (PSPD) across coarctation of the aorta for diagnosing the severity of coarctation. Traditional non-invasive estimates of pressure drop from the ultrasound can underestimate the severity and invasive measurements by cardiac catheterization can carry risks for patients. To address the issues, we employ computational fluid dynamics (CFD) computation to accurately predict the PSPD across a coarctation based on cardiac magnetic resonance (CMR) imaging data and cuff pressure measurements from one arm. The boundary conditions of a patient-specific aorta model are specified at the inlet of the ascending aorta by using the time-dependent blood velocity, and the outlets of descending aorta and supra aortic branches by using a 3-element Windkessel model. To estimate the parameters of the Windkessel model, steady flow simulations were performed using the time-averaged flow rates in the ascending aorta, descending aorta, and two of the three supra aortic branches. The mean cuff pressure from one arm was specified at the outlet of one of the supra aortic branches. The CFD predicted PSPDs of 5 patients (n=5) were compared with the invasively measured pressure drops obtained by catheterization. The PSPDs were accurately predicted (mean µ=0.3mmHg, standard deviation σ =4.3mmHg) in coarctation of the aorta using completely non-invasive flow and cuff pressure data. The results of our study indicate that the proposed method could potentially replace invasive measurements for estimating the severity of coarctations.Clinical relevance-Peak systolic pressure drop is an indicator of the severity of coarctation of the aorta. It can be predicted without any additional risks to patients using non-invasive cuff pressure and flow data from CMR.

Effects of pannus formation on the flow around a bileaflet mechanical heart valve.

Some patients with a bileaflet mechanical heart valve (BMHV) show significant increases in the transvalvular pressure drop and abnormal leaflet motion due to a pannus (an abnormal fibrovascular tissue) formed on the ventricular side, even in the absence of physical contact between the pannus and leaflets. We investigate the effects of the pannus shape (circular or semi-circular ring), implantation location and height on the leaflet motion, flow structure and transvalvular pressure drop using numerical simulations. The valve model considered resembles a 25 mm masters HP valve. The mean systolic pressure drop is significantly increased with increasing pannus height, irrespective of its implantation orientation. Near the peak inflow rate, the flow behind the pannus becomes highly turbulent, and the transvalvular pressure drop is markedly increased by the pannus. At the end of valve opening and the start of valve closing, oscillatory motions of the leaflets occur due to periodic shedding of vortex rings behind the pannus, and their amplitudes become large with increasing pannus height. When the pannus shape is asymmetric (e.g., a semi-circular ring) and its height reaches about 0.1D (D (= 25 mm) is the diameter of an aorta), abnormal leaflet motions occur: two leaflets move asymmetrically, and valve closing is delayed in time or incomplete, which increases the regurgitation volume. The peak energy loss coefficients due to panni are obtained from simulation data and compared with those predicted by a one-dimensional model. The comparison indicates that the one-dimensional model is applicable for the BMHV with and without pannus.

Global and regional myocardial function and outcomes after transcatheter aortic valve implantation for aortic stenosis and preserved ejection fraction.

To investigate the effects of transcatheter aortic valve implantation (TAVI) on early recovery of global and segmental myocardial function in patients with severe symptomatic aortic stenosis and preserved left ventricular ejection fraction (LVEF) and to determine if parameters of deformation correlate with outcomes. The echocardiographic (strain analysis) and outcome (hospitalizations because of heart failure and mortality) data of 62 consecutive patients with preserved LVEF (64.54 ± 7.97%) who underwent CoreValve prosthesis implantation were examined. Early after TAVI (5 ± 3.9 days), no significant changes in LVEF or diastolic function were found, while a significant drop of systolic pulmonary artery pressure (PAP) occurred (42.3 ± 14.9 vs. 38.1 ± 13.9 mmHg, P = 0.028). After TAVI global longitudinal strain (GLS) did not change significantly, whereas significant improvement in global mid-level left ventricular (LV) radial strain (GRS) was found (-16.71 ± 2.42 vs. -17.32 ± 3.25%; P = 0.33; 16.57 ± 6.6 vs. 19.48 ± 5.97%, P = 0.018, respectively). Early significant recovery of longitudinal strain was found in basal lateral and anteroseptal segments (P = 0.038 and 0.048). Regional radial strain at the level of papillary muscles [P = 0.038 mid-lateral, P < 0.001 mid-anteroseptum (RSAS)] also improved. There was a significant LV mass index reduction in the late follow-up (152.42 ± 53.21 vs. 136.24 ± 56.67 g/m, P = 0.04). Mean follow-up period was 3.5 ± 1.9 years. Parameters associated with worse outcomes in univariable analysis were RSAS pre-TAVI, LV end-diastolic diameter after TAVI, relative wall thickness, and mitral E and E/A after TAVI. Global and regional indices of myocardial function improved early after TAVI, suggesting the potential of myocardium to recover with a reduced risk for clinical deterioration.

Feasibility of ultrasound-assisted catheter-directed thrombolysis for submassive pulmonary embolism: A meta-analysis of case series.

During the past few years, there has been a surge in the use of ultrasound-assisted catheter-directed thrombolysis (UACDT) for submassive pulmonary embolism (SPE). However, few studies evaluated the feasibility of UACDT for SPE. To evaluate the feasibility of UACDT in treating SPE. A comprehensive search of online databases was performed. Search terms UACDT in SPE were entered into PubMed, Embase, Scopus and the Cochrane Library to identify related articles published until October 2018. A quality assessment and data extraction were performed by two researchers. Meta-analysis was performed using R statistical software. Twelve studies with 485 patients were included in this meta-analysis. The pooled right ventricular/left ventricular ratio decrease and pulmonary artery systolic pressure drop after treatment was -0.34 (95% CI: -0.43, -0.25) and -15.05 (95% CI: -18.10, -12.00) mm Hg, respectively. The pooled major bleeding rate was 1.0% (95% CI: 0.0%, 3.0%), and the in-hospital mortality was 0.0% (95% CI: 0.0%, 1.0%). This up to data meta-analysis confirms that UACDT is a feasible treatment for SPE.

Incidence and predictors of acute kidney injury in patients undergoing proximal protected carotid artery stenting.

Many studies have analysed the occurrence of acute kidney injury (AKI) after percutaneous coronary intervention (PCI) but there are limited data relating to AKI risk in patients undergoing carotid artery stenting (CAS). The aim of this study was to determine the incidence and predictors of AKI in patients undergoing proximal protected CAS. We analysed 456 patients undergoing proximal protected CAS. A binomial multivariate logistic model was developed including patients' clinical and angiographic/procedural characteristics. AKI (defined as an sCr increase ≥0.3 mg/dl or ≥1.5-fold sCr increase from baseline or more than 50% increase from baseline, within 48 hours post procedure) occurred in 155 patients (34%). AKI patients were more frequently affected by hypertension, diabetes, dyslipidaemia and anaemia, and presented lower renal function at baseline. Higher contrast volume to creatinine clearance ratio (2.40±1.44 vs. 2.08±1.15; p=0.01), lower post-procedural mean arterial pressure (MAP) (94.3±17.7 vs. 99.6±18.5 mmHg; p=0.003) and a more frequent post-procedural systolic pressure drop (∆SBP >50 mmHg) (23.9% vs. 14.3%, p=0.01) were observed in the AKI group of patients. At multivariate analysis, independent predictors of AKI were ∆SBP >50 mmHg, diabetes mellitus and dyslipidaemia. AKI can occur quite frequently after proximal protected CAS and is related to clinical and procedural features. These data should be confirmed in larger registries or randomised trials.