Peripheral skin cooling during hyper-gravity: hemodynamic reactions.

Introduction: Orthostatic dysregulation occurs during exposure to an increased gravitational vector and is especially common upon re-entering standard Earth gravity (1 g) after an extended period in microgravity (0 g). External peripheral skin cooling (PSC) has recently been described as a potent countermeasure against orthostatic dysregulation during heat stress and in lower body negative pressure (LBNP) studies. We therefore hypothesized that PSC may also be an effective countermeasure during hyper-gravity exposure (+Gz). Methods: To investigate this, we designed a randomized short-arm human centrifuge (SAHC) experiment ("Coolspin") to investigate whether PSC could act as a stabilizing factor in cardiovascular function during +Gz. Artificial gravity between +1 g and +4 g was generated by a SAHC. 18 healthy male volunteers completed two runs in the SAHC. PSC was applied during one of the two runs and the other run was conducted without cooling. Each run consisted of a 10-min baseline trial followed by a +Gz step protocol marked by increasing g-forces, with each step being 3 min long. The following parameters were measured: blood pressure (BP), heart rate (HR), stroke volume (SV), total peripheral resistance (TPR), cardiac output (CO). Furthermore, a cumulative stress index for each subject was calculated. Results: +Gz led to significant changes in primary as well as in secondary outcome parameters such as HR, SV, TPR, CO, and BP. However, none of the primary outcome parameters (HR, cumulative stress-index, BP) nor secondary outcome parameters (SV, TPR, CO) showed any significant differences-whether the subject was cooled or not cooled. Systolic BP did, however, tend to be higher amongst the PSC group. Conclusion: In conclusion, PSC during +Gz did not confer any significant impact on hemodynamic activity or orthostatic stability during +Gz. This may be due to lower PSC responsiveness of the test subjects, or an insufficient level of body surface area used for cooling. Further investigations are warranted in order to comprehensively pinpoint the exact degree of PSC needed to serve as a useful countermeasure system during +Gz.

Acute Kidney Injury With a Miniaturized Extracorporeal Circuit for Neonatal Cardiopulmonary Bypass.

OBJECTIVES: The objectives of this study were to evaluate the incidence and to identify risk factors for acute kidney injury (AKI) in neonates undergoing cardiopulmonary bypass (CPB) with a miniaturized bloodless primed extracorporeal circuit. DESIGN: A retrospective cohort study. SETTING: A single-center, tertiary academic hospital. PARTICIPANTS: Data of 462 patients were analyzed. INTERVENTIONS: With a retrospective analysis of neonates undergoing CPB with bloodless priming between May 2007 and August 2019, the incidence of AKI was determined according to the neonatal Kidney Disease: Improving Global Outcomes classification. Multivariate logistic regression analyses were performed to determine risk factors for AKI. MEASUREMENTS AND MAIN RESULTS: The incidence of AKI was 41.1% (190 of 462); 30.3% (n = 140) had mild stage 1, 6.5% (n = 30) reached stage 2, and 4.3% (n = 20) reached stage 3. Multivariate logistic regression showed that degree of hypothermia (p = 0.05), duration of CPB (p = 0.03), and lower baseline serum creatinine (p < 0.001) were associated independently with AKI. In the authors' patient population, patients without transfusion of donor-derived erythrocytes had a lower incidence of AKI (p = 0.003). AKI stages 2 and 3 were associated with longer duration of mechanical ventilation (p = 0.008) and increased length of stay in the intensive care unit (p = 0.03). CONCLUSIONS: With a miniaturized CPB circuit and bloodless priming, the AKI incidence was well within the range consistent with previously reported studies from other institutions.

Orthostatic Resiliency During Successive Hypoxic, Hypoxic Orthostatic Challenge: Successful vs. Unsuccessful Cardiovascular and Oxygenation Strategies.

Introduction: Rapid environmental changes, such as successive hypoxic-hypoxic orthostatic challenges (SHHOC) occur in the aerospace environment, and the ability to remain orthostatically resilient (OR) relies upon orchestration of physiological counter-responses. Counter-responses adjusting for hypoxia may conflict with orthostatic responses, and a misorchestration can lead to orthostatic intolerance (OI). The goal of this study was to pinpoint specific cardiovascular and oxygenation factors associated with OR during a simulated SHHOC. Methods: Thirty one men underwent a simulated SHHOC consisting of baseline (P0), normobaric hypoxia (Fi02 = 12%, P1), and max 60 s of hypoxic lower body negative pressure (LBNP, P2). Alongside anthropometric variables, non-invasive cardiovascular, central and peripheral tissue oxygenation parameters, were recorded. OI was defined as hemodynamic collapse during SHHOC. Comparison of anthropometric, cardiovascular, and oxygenation parameters between OR and OI was performed via Student's t-test. Within groups, a repeated measures ANOVA test with Holm-Sidak post hoc test was performed. Performance diagnostics were performed to assess factors associated with OR/OI (sensitivity, specificity, positive predictive value PPV, and odd's ratio OR). Results: Only 9/31 were OR, and 22/31 were OI. OR had significantly greater body mass index (BMI), weight, peripheral Sp02, longer R-R Interval (RRI) and lower heart rate (HR) at P0. During P1 OR exhibited significantly higher cardiac index (CI), stroke volume index (SVI), and lower systemic vascular resistance index (SVRI) than OI. Both groups exhibited a significant decrease in cerebral oxygenation (TOIc) with an increase in cerebral deoxygenated hemoglobin (dHbc), while the OI group showed a significant decrease in cerebral oxygenated hemoglobin (02Hbc) and peripheral oxygenation (TOIp) with an increase in peripheral deoxygenated hemoglobin (dHbp). During P2, OR maintained significantly greater CI, systolic, mean, and diastolic pressure (SAP, MAP, DAP), with a shortened RRI compared to the OI group, while central and peripheral oxygenation were not different. Body weight and BMI both showed high sensitivity (0.95), low specificity (0.33), a PPV of 0.78, with an OR of 0.92, and 0.61. P0 RRI showed a sensitivity of 0.95, specificity of 0.22, PPV 0.75, and OR of 0.99. Delta SVI had the highest performance diagnostics during P1 (sensitivity 0.91, specificity 0.44, PPV 0.79, and OR 0.8). Delta SAP had the highest overall performance diagnostics for P2 (sensitivity 0.95, specificity 0.67, PPV 0.87, and OR 0.9). Discussion: Maintaining OR during SHHOC is reliant upon greater BMI, body weight, longer RRI, and lower HR at baseline, while increasing CI and SVI, minimizing peripheral 02 utilization and decreasing SVRI during hypoxia. During hypoxic LBNP, the ability to remain OR is dependent upon maintaining SAP, via CI increases rather than SVRI. Cerebral oxygenation parameters, beyond 02Hbc during P1 did not differ between groups, suggesting that the during acute hypoxia, an increase in cerebral 02 consumption, coupled with increased peripheral 02 utilization does seem to play a role in OI risk during SHHOC. However, cardiovascular factors such as SVI are of more value in assessing OR/OI risk. The results can be used to implement effective aerospace crew physiological monitoring strategies.

Chronic Naltrexone Therapy Is Associated with Improved Cardiac Function in Volume Overloaded Rats.

PURPOSE: Myocardial opioid receptors were demonstrated in animals and humans and seem to colocalize with membranous and sarcolemmal calcium channels of the excitation-contraction coupling in the left ventricle (LV). Therefore, this study investigated whether blockade of the cardiac opioid system by naltrexone would affect cardiac function and neurohumoral parameters in Wistar rats with volume overload-induced heart failure. METHODS: Volume overload in Wistar rats was induced by an aortocaval fistula (ACF). Left ventricular cardiac opioid receptors were identified by immunohistochemistry and their messenger ribonucleic acid (mRNA) as well as their endogenous ligand mRNA quantified by real-time polymerase chain reaction (RT-PCR). Following continuous delivery of either the opioid receptor antagonist naltrexone or vehicle via minipumps (n = 5 rats each), hemodynamic and humoral parameters were assessed 28 days after ACF induction. Sham-operated animals served as controls. RESULTS: In ACF rats mu-, delta-, and kappa-opioid receptors colocalized with voltage-gated L-type Ca2+ channels in left ventricular cardiomyocytes. Chronic naltrexone treatment of ACF rats reduced central venous pressure (CVP) and left ventricular end-diastolic pressure (LVEDP), and improved systolic and diastolic left ventricular functions. Concomitantly, rat brain natriuretic peptide (rBNP-45) and angiotensin-2 plasma concentrations which were elevated during ACF were significantly diminished following naltrexone treatment. In parallel, chronic naltrexone significantly reduced mu-, delta-, and kappa-opioid receptor mRNA, while it increased the endogenous opioid peptide mRNA compared to controls. CONCLUSION: Opioid receptor blockade by naltrexone leads to improved LV function and decreases in rBNP-45 and angiotensin-2 plasma levels. In parallel, naltrexone resulted in opioid receptor mRNA downregulation and an elevated intrinsic tone of endogenous opioid peptides possibly reflecting a potentially cardiodepressant effect of the cardiac opioid system during volume overload.

Incidence of acute type A aortic dissection in emergency departments.

Due to the symptoms, patients with acute type A aortic dissection are first seen by the ambulance service and diagnosed at the emergency department. How often an aortic dissection occurs in an emergency department per year has been studied. The incidence in the emergency department may be used as a quality marker of differential diagnostics of acute chest pain. A multi-institutional retrospective study with the municipal Berlin hospital chain Vivantes and its Department of Pathology and the Charité - University Medicine Berlin was performed. From the Berlin Hospital Society, the annual numbers of publicly insured emergency patients were obtained. Between 2006 and 2016, 631 aortic dissections were identified. The total number of patients treated in the emergency departments (n = 12,790,577) was used to calculate the "emergency department incidence." The autopsy data from six clinics allowed an estimate on how many acute type A aortic dissections remained undetected. Across all Berlin hospitals, the emergency department incidence of acute type A aortic dissection was 5.24 cases in 100,000 patients per year. In tertiary referral hospitals and, particularly, in university hospitals the respective incidences were markedly higher (6.7 and 12.4, respectively). Based on the autopsy results, about 50% of the acute type A aortic dissection may remain undetected, which would double the reported incidences. Among different hospital types the emergency department incidences of acute type A aortic dissection vary between 5.93/100,000 and 24.92/100,000. Aortic dissection; Incidence; Emergency Department; Epidemiology.

Acute type A aortic dissection: Aortic Dissection Detection Risk Score in emergency care - surgical delay because of initial misdiagnosis.

BACKGROUND: Acute type A aortic dissection requires immediate surgical treatment, but the correct diagnosis is often delayed. This study aimed to analyse how initial misdiagnosis affected the time intervals before surgical treatment, symptoms associated with correct or incorrect initial diagnosis and the potential of the Aortic Dissection Detection Risk Score to improve the sensitivity of initial diagnosis. METHODS: We conducted a retrospective analysis of 350 patients with acute type A aortic dissection. Patients were divided into two groups: initial misdiagnosis (group 0) and correct initial diagnosis of acute type A aortic dissection (group 1). Symptoms were analysed as predictors for the correct or incorrect initial diagnosis by multivariate analysis. Based on these findings, the Aortic Dissection Detection Risk Score was calculated retrospectively; a result ⩾2 was defined as a positive score. RESULTS: The early suspicion of aortic dissection significantly shortened the median time from pain to surgical correction from 8.6 h in patients with an initial misdiagnosis to 5.5 h in patients with the correct initial diagnosis (p<0.001). Of all acute type A aortic dissection patients, 49% had a positive Aortic Dissection Detection Risk Score. Of all initial misdiagnosed patients, 41% had a positive score (⩾2). The presence of lumbar pain (p<0.001), any paresis (p=0.037) and sweating (p=0.042) was more likely to lead to the correct initial diagnosis. CONCLUSION: An early consideration of acute aortic dissection may reduce the delay of surgical care. The suggested Aortic Dissection Detection Risk Score may be a useful tool to improve the preclinical assessment.

Cardiac output measurement during exercise in COPD: A comparison of dye dilution and impedance cardiography.

INTRODUCTION: Impedance cardiography (IC) derived from morphological analysis of the thoracic impedance signal is now commonly used for noninvasive assessment of cardiac output (CO) at rest and during exercise. However, in Chronic Obstructive Pulmonary Disease (COPD), conflicting findings put its accuracy into question. OBJECTIVES: We therefore compared concurrent CO measurements captured by IC (PhysioFlow: COIC ) and by the indocyanine green dye dilution method (CODD ) in patients with COPD. METHODS: Fifty paired CO measurements were concurrently obtained using the two methods from 10 patients (FEV1 : 50.5 ± 17.5% predicted) at rest and during cycling at 25%, 50%, 75% and 100% peak work rate. RESULTS: From rest to peak exercise COIC and CODD were strongly correlated (r = 0.986, P < 0.001). The mean absolute and percentage differences between COIC and CODD were 1.08 L/min (limits of agreement (LoA): 0.05-2.11 L/min) and 18 ± 2%, respectively, with IC yielding systematically higher values. Bland-Altman analysis indicated that during exercise only 7 of the 50 paired measurements differed by more than 20%. When data were expressed as changes from rest, correlations and agreement between the two methods remained strong over the entire exercise range (r = 0.974, P < 0.001, with no significant difference: 0.19 L/min; LoA: -0.76 to 1.15 L/min). Oxygen uptake (VO2 ) and CODD were linearly related: r = 0.893 (P < 0.001), CODD = 5.94 × VO2 + 2.27 L/min. Similar results were obtained for VO2 and COIC (r = 0.885, P < 0.001, COIC = 6.00 × VO2 + 3.30 L/min). CONCLUSIONS: These findings suggest that IC provides an acceptable CO measurement from rest to peak cycling exercise in patients with COPD.

Left Ventricular Systolic Dysfunction in Patients With Type-A Aortic Dissection Is Associated With 30-Day Mortality.

OBJECTIVE: The aim of this study was to analyze preoperative and postoperative echocardiographic parameters in patients with type-A acute aortic dissection (ATAAD) and to analyze whether impaired preoperative left ventricular function was associated with short- and long-term survival. To enable multivariable analysis, established risk factors of ATAAD were analyzed as well. DESIGN: Retrospective single-center study. SETTING: The German Heart Center Berlin. PARTICIPANTS: The retrospective data of 512 patients with ATAAD who were treated between 2006 and 2014 were analyzed. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Preoperative versus postoperative left ventricular ejection fraction (LVEF), right ventricular ejection fraction, left ventricular end-diastolic diameter, and right ventricular end-diastolic diameter were not significantly different, and the mean values were within the reference ranges. Because of the surgical intervention, incidences and severities of aortic regurgitation and pericardial effusion decreased. In multivariable logistic analysis, the authors identified age (odds ratio [OR] 1.04, p < 0.001), preoperative LVEF ≤35% (OR 2.20, p = 0.003), any ischemia (Penn non-Aa) (OR 2.15, p < 0.001), and longer cardiopulmonary bypass time (OR 1.04, p < 0.001) as independent predictors of 30-day mortality. Cardiopulmonary resuscitation, tamponade, or shock, and pre-existing cardiac disease, were not predictors of death. CONCLUSION: After surgery, aortic insufficiency and pericardial effusion decreased, whereas cardiac functional parameters did not change. Severe LV dysfunction was identified as a new independent predictor of 30-day mortality.

Limb Skin Temperature as a Tool to Predict Orthostatic Instability.

Orthostatic instability is one of the main consequences of weightlessness or gravity challenge and plays as well a crucial role in public health, being one of the most frequent disease of aging. Therefore, the assessment of effective countermeasures, or even the possibility to predict, and thus prevent orthostatic instability is of great importance. Heat stress affects orthostatic stability and may lead to impaired consciousness and decrease in cerebral perfusion, specifically during the exposure to G-forces. Conversely, peripheral cooling can prevent orthostatic intolerance - even in normothermic healthy subjects. Indicators of peripheral vasodilation, as elevated skin surface temperatures, may mirror blood decentralization and an increased risk of orthostatic instability. Therefore, the aim of this study was to quantify orthostatic instability risk, by assessing in 20 fighter jet pilot candidates' cutaneous limb temperatures, with respect to the occurrence of G-force-induced almost loss of consciousness (ALOC), before and during exposure to a push-pull maneuver, i.e., head-down tilt, combined with lower body negative pressure. Peripheral skin temperatures from the upper and lower (both proximal and distal) extremities and core body temperature via heat-flux approach (i.e., the Double Sensor), were continuously measured before and during the maneuver. The 55% of subjects that suffered an ALOC during the procedure had higher upper arm and thigh temperatures at baseline compared to the 45% that remained stable. No difference in baseline core body temperature and distal limbs (both upper and lower) skin temperatures were found between the two groups. Therefore, peripheral skin temperature data could be considered a predicting factor for ALOC, prior to rapid onset acceleration. Moreover, these findings could also find applications in patient care settings such as in intensive care units.

Gender-Specific Cardiovascular Reactions to +Gz Interval Training on a Short Arm Human Centrifuge.

Cardiovascular deconditioning occurs in astronauts during microgravity exposure, and may lead to post-flight orthostatic intolerance, which is more prevalent in women than men. Intermittent artificial gravity is a potential countermeasure, which can effectively train the cardiovascular mechanisms responsible for maintaining orthostatic integrity. Since cardiovascular responses may differ between women and men during gravitational challenges, information regarding gender specific responses during intermittent artificial gravity exposure plays a crucial role in countermeasure strategies. This study implemented a +Gz interval training protocol using a ground based short arm human centrifuge, in order to assess its effectiveness in stimulating the components of orthostatic integrity, such as diastolic blood pressure, heart rate and vascular resistance amongst both genders. Twenty-eight participants (12 men/16 women) underwent a two-round graded +1/2/1 Gz profile, with each +Gz phase lasting 4 min. Cardiovascular parameters from each phase (averaged last 60 sec) were analyzed for significant changes with respect to baseline values. Twelve men and eleven women completed the session without interruption, while five women experienced an orthostatic event. These women had a significantly greater height and baseline mean arterial pressure than their counterparts. Throughout the +Gz interval session, women who completed the session exhibited significant increases in heart rate and systemic vascular resistance index throughout all +Gz phases, while exhibiting increases in diastolic blood pressure during several +Gz phases. Men expressed significant increases from baseline in diastolic blood pressure throughout the session with heart rate increases during the +2Gz phases, while no significant changes in vascular resistance were recorded. Furthermore, women exhibited non-significantly higher heart rates over men during all phases of +Gz. Based on these findings, this protocol proved to consistently stimulate the cardiovascular systems involved in orthostatic integrity to a larger extent amongst women than men. Thus the +Gz gradients used for this interval protocol may be beneficial for women as a countermeasure against microgravity induced cardiovascular deconditioning, whereas men may require higher +Gz gradients. Lastly, this study indicates that gender specific cardiovascular reactions are apparent during graded +Gz exposure while no significant differences regarding cardiovascular responses were found between women and men during intermittent artificial gravity training.

Coronary Microcirculation in Ischemic Heart Disease.

BACKGROUND: Ischemic heart disease has long been considered to be exlusively caused by stenosis or occlusion. However, the coronary microcirculation too may play an important role in ischemic conditions. Also, the crucial role of microvessels in not only regulating blood flow on a local level but also mediating vascular permeability or inflammatory responses has been recognized. OBJECTIVE: To review important physiological and pathophysiological mechanisms of coronary microcirculatory control with focus on heterogeneity of local perfusion, microvascular permeability and inflammation. METHOD: Selective research of the literature. RESULTS: Heterogeneity is a characteristic of microvascular networks and affects structural and functional parameters such as vessel diameter, length, and connection pattern, flow velocity, wall shear stress, and oxygenation. Microvascular networks are optimized to meet the metabolic demand of all tissue compartments. This requires continuous vascular adaptation regulated by local hemodynamic and metabolic stimuli. Compromising this regulation results in functional arterio-venous shunting and tissue areas with either hyperperfusion or hypoxia in close proximity. In ischemia-reperfusion, increased microvascular permeability may aggravate tissue hypoxia by increasing extravascular pressure and seems to contribute to adverse myocardial remodeling. Transendothelial transport mechanisms and deterioration of the endothelial glycocalyx seem to be major contributors to tissue edema. Also in the context of ischemia-reperfusion, an inflammatory response mediated by venular endothelium expressing specific adhesion molecules contributes to tissue injury. However, anti-inflammatory therapies failed in clinical studies and a multi-targeted approach for cardiac protection is required. CONCLUSION: Disturbances of the coronary microcirculation are involved in different pathophysiological aspects of reperfusion injury.

Near-infrared spectroscopy using indocyanine green dye for minimally invasive measurement of respiratory and leg muscle blood flow in patients with COPD.

Reliability of near-infrared spectroscopy, measuring indocyanine green (ICG) for minimally invasive assessment of relative muscle blood flow during exercise has been examined in fit young individuals but not in chronic obstructive pulmonary disease (COPD). Here we ask whether it could be used to evaluate respiratory and locomotor muscle perfusion in COPD patients. Vastus lateralis muscle blood flow (MBF, the reference method calculated from arterial and muscle ICG concentration curves) and a blood flow index [BFI, calculated using only the (same) muscle ICG concentration curves] were compared in 10 patients (forced expiratory volume in 1 s: 51 ± 6% predicted) at rest and during cycling at 25, 50, 75, and 100% of peak work rate (WRpeak). Intercostal muscle MBF and BFI were also compared during isocapnic hyperpnea at rest, reproducing ventilation levels up to those at WRpeak. Intercostal and vastus lateralis BFI increased with increasing ventilation during hyperpnea (from 2.5 ± 0.3 to 4.5 ± 0.7 nM/s) and cycling load (from 1.0 ± 0.2 to 12.8 ± 1.9 nM/s), respectively. There were strong correlations between BFI and MBF for both intercostal ( r = 0.993 group mean data, r = 0.872 individual data) and vastus lateralis ( r = 0.994 group mean data, r = 0.895 individual data). Fold changes from rest in BFI and MBF did not differ for either the intercostal muscles or the vastus lateralis. Group mean BFI data showed strong interrelationships with respiratory and cycling workload, and whole body metabolic demand ( r ranged from 0.913 to 0.989) simultaneously recorded during exercise. We conclude that BFI is a reliable and minimally invasive tool for evaluating relative changes in respiratory and locomotor muscle perfusion from rest to peak exercise in COPD patient groups. NEW & NOTEWORTHY We show that noninvasive near-infrared spectroscopic (NIRS) detection of indocyanine green dye (ICG) after peripheral venous injection adequately reflects intercostal and locomotor muscle perfusion during exercise and hyperpnea in patients with chronic obstructive pulmonary disease (COPD). Mean, individual, and fold change responses from rest to exercise or hyperpnea correlated closely with the reference method, which requires arterial sampling. NIRS-ICG is a reliable, robust, and essentially noninvasive tool for assessing relative changes in intercostal and locomotor muscle perfusion in COPD patient groups.

Prognostic value of 3-dimensional echocardiographical heart volume assessment in patients scheduled for left ventricular assist device implantation.

OBJECTIVES: Left ventricular assist device (LVAD) support is an increasingly important and successful therapeutic option for patients with end-stage heart failure. As chronic heart failure progresses, the left and right ventricles adapt by enlarging its volume and patients present for LVAD implantation with varying degrees of dilatation. By quantitatively assessing right ventricular (RV) and left ventricular (LV) volumes using 3D transoesophageal echocardiography and correlating the findings with clinical outcomes, we aim to investigate the prognostic value of LV and RV volumes for early survival after LVAD implantation. METHODS: This is a single-centre, non-randomized diagnostic cohort study using prospectively collected clinical and 3D echocardiographic data from 65 patients scheduled for LVAD implantation, using centrifugal pumps for long-term support (HeartWare and HeartMate 3). The primary end-point for this study is 60-day mortality, with longer term survival as a secondary end-point. RESULTS: We divided our cohort group into survivors and non-survivors at 60 days [49 patients (75%) and 16 patients (25%), respectively]. Right to left end-diastolic ratio assessed by 2D echocardiography was significantly higher in the 60-day non-survivors group (0.70 ± 0.09 vs 0.62 ± 0.11; P = 0.01). Indexed end-diastolic volume parameters (LV, RV and overall heart) showed significant differences among the groups and were higher in the 60-day survivors group (LV volume 154 ± 51 ml/m2 vs 110 ± 40 ml/m2, P = 0.004; RV volume 96 ± 27 ml/m2 vs 80 ± 23 ml/m2, P = 0.05; heart 250 ± 64 ml/m2 vs 190 ± 57 ml/m2, P= 0.003). To investigate haemodynamic and echocardiographic parameters, the right to left end-diastolic ratio and indexed RV end-diastolic volume were associated with 60-day mortality in the logistic regression analysis. The Kaplan-Meier survival curves for patients with indexed RV end-diastolic volume >82 ml/m2 vs indexed RV end-diastolic volume ≤82 ml/m2 showed better 1-year survival (P = 0.005) for the group with more RV dilatation. CONCLUSIONS: Patients with moderately increased end-diastolic RV volume index carry a higher postoperative risk, while severe RV dilatation seems to be protective. In future, postoperative management of patients with moderately dilated RVs should be focussed on adjusting individually appropriate LVAD flows and providing frequent follow-up.

Health-related quality of life of patients after surgery for acute Type A aortic dissection.

OBJECTIVES: Acute Type A aortic dissection (ATAAD) and the ensuing surgical therapy may be experienced as a traumatic event by patients. This study aimed at analysing the prevalence of post-traumatic stress disorder (PTSD) and the physical and mental well-being of survivors of surgically treated ATAAD. METHODS: A total of 393 survivors were contacted and asked to fill in various health questionnaires. RESULTS: Two hundred and ten (53%) patients returned the questionnaires. The mean follow-up was 51 ± 27.8 months. The results showed that 67.6% had high blood pressure, 12.9% had pre-existing diseases of the aorta and 31.5% or 27% of these groups were at risk for PTSD according to the health questionnaires. Duration of intensive care unit or hospital stay had no effect on the risk for PTSD. According to the questionnaire, Short Form 12, physical and mental well-being was significantly reduced in the patients compared to a large German norm sample, even after adjustment for differences in age between the 2 cohorts. Physical activity prior to the event was associated with improved physical and mental well-being but did not reduce the risk for PTSD. CONCLUSIONS: Emergency surgery for ATAAD is associated with high risk for PTSD, which seems to negatively affect physical and mental well-being. More efforts should be directed at prevention and early diagnosis and therapy of PTSD. This study has evaluated 8-year trends in the presentation, diagnosis and outcomes such as physical and mental measures and prevalence rates of PTSD in patients who have undergone an emergency operation for ATAAD.

Asanguineous priming of miniaturized paediatric cardiopulmonary bypass circuits for congenital heart surgery: independent predictors associated with transfusion requirements and effects on postoperative morbidity.

OBJECTIVES: In paediatric cardiac surgery, body weight-adjusted miniaturized cardiopulmonary bypass (CPB) circuits within a comprehensive blood-sparing approach can reduce transfusion requirements. Haemodilution resulting from mixing the patient's blood with a CPB crystalloid solution may be reduced to the extent that asanguineous priming becomes possible. Therefore, we adopted asanguineous priming in our clinical routine. Our goal was to report the effects of asanguineous priming on transfusion requirements, clinical features associated with transfusion and effects on in-hospital morbidity. METHODS: Data of all paediatric patients with body weights up to 15 kg treated within a 2-year period between May 2013 and May 2015 were retrospectively analysed. The incidence of transfusions was analysed and periprocedural haemoglobin concentrations were evaluated. Predictors associated with transfusion requirements, duration of ventilation or length of stay in the intensive care unit were evaluated by multivariable analyses. RESULTS: Data from 579 patients with body weights up to 15 kg were analysed. The ability to avoid transfusion depended on body weight: in patients <3 kg, the rate (95% confidence interval) of transfusion during CPB was 0.53 (0.37-0.69), and in patients >8 kg, the rate was 0.14 (0.10-0.19). The respective rates of transfusions throughout the hospital stay were 1.00 (0.90-1.00) and 0.67 (0.60-0.73). Body weight, preoperative haemoglobin concentration, duration of CPB and palliative surgery were independently associated with transfusion during CPB. Transfusion, particularly transfusion during CPB, was independently associated with longer mechanical ventilation time (hazard ratio 3.52, confidence interval 2.66-4.65) and length of stay in the intensive care unit (hazard ratio 2.52, confidence interval 1.91-3.32). CONCLUSIONS: Asanguineous priming is feasible using miniaturized CPB circuits. It may help to avoid blood transfusions in patients on CPB and reduce transfusion requirements and transfusion-related morbidity.

CardioScape mapping the cardiovascular funding landscape in Europe.

Aims: The burden of cardiovascular disease is increasing worldwide, which has to be reflected by cardiovascular (CV) research in Europe. CardioScape, a FP7 funded project initiated by the European Society of Cardiology (ESC), identified where CV research is performed, how it is funded and by whom. It could be transformed into an on-line and up-to-date resource of great relevance for researchers, funding bodies and policymakers and could be a role model for mapping CV research funding in Europe and beyond. Methods and results: Relevant funding bodies in 28 European Union (EU) countries were identified by a multistep process involving experts in each country. Projects above a funding threshold of 100 k€ during the period 2010-2012 were included using a standard questionnaire. Results were classified by experts and an adaptive text analysis software to a CV-research taxonomy, integrating existing schemes from ESC journals and congresses. An on-line query portal was set up to allow different users to interrogate the database according to their specific viewpoints. Conclusion: CV-research funding varies strongly between different nations with the EU providing 37% of total available project funding and clear geographical gradients exist. Data allow in depth comparison of funding for different research areas and led to a number of recommendations by the consortium. CardioScape can support CV research by aiding researchers, funding agencies and policy makers in their strategic decisions thus improving research quality if CardioScape strategy and technology becomes the basis of a continuously updated and expanded European wide publicly accessible database.

Incidence and echocardiographic predictors of early postoperative right ventricular dysfunction following left ventricular assist implantation in paediatric patients.

OBJECTIVES: Left ventricular assist device implantation is an established therapy for paediatric patients with end-stage heart failure. Early right ventricular dysfunction (RVD) after implantation still remains a challenge in the postoperative period. This study sought to determine the incidence of RVD and to identify echocardiographic predictors of RVD in paediatric patients, as well describing associated clinical outcome. METHODS: Prospectively collected preoperative echocardiographic, haemodynamic, demographic and biochemical data from 48 patients scheduled for left ventricular assist device implantation were evaluated. Incidence of high central venous pressure, decreased central venous saturation, high inotropic support requirements or need for mechanical support of the right ventricle during the first 48 h after implantation were used to define RVD. Echocardiographic assessments of right ventricular geometry, function using linear dimensions, areas and tricuspid annular plane systolic excursion (TAPSE) were performed preoperatively and the relative relationships between these parameters were evaluated. RESULTS: We included 48 consecutive paediatric patients (median age 5 years, range 0-17; median weight 15.9 kg, range 3.6-91). According to our criteria, 24 (50%) patients developed RVD. TAPSE as the parameter for assessment of longitudinal systolic function was significantly lower in this group (P = 0.01). The difference became even more pronounced after normalization to the RV end-diastolic diameter in long axis with P = 0.003. The odds ratio for patients with TAPSE/RV end-diastolic diameter in long axis <17.1% to develop RVD was 7.7 (P = 0.002). CONCLUSIONS: RVD occurs frequently in paediatric patients after left ventricular assist device. TAPSE, normalized to the RV end-diastolic diameter, may help to identify patients at risk for RVD. The predictive value of this parameter supports decision making to plan for adequate pharmacological support or consider early upgrading to mechanical RV support.

Accuracy of predicted haemoglobin concentration on cardiopulmonary bypass in paediatric cardiac surgery: effect of different formulae for estimating patient blood volume.

INTRODUCTION: When applying a blood-conserving approach in paediatric cardiac surgery with the aim of reducing the transfusion of homologous blood products, the decision to use blood or blood-free priming of the cardiopulmonary bypass (CPB) circuit is often based on the predicted haemoglobin concentration (Hb) as derived from the pre-CPB Hb, the prime volume and the estimated blood volume. We assessed the accuracy of this approach and whether it may be improved by using more sophisticated methods of estimating the blood volume. PATIENTS AND METHODS: Data from 522 paediatric cardiac surgery patients treated with CPB with blood-free priming in a 2-year period from May 2013 to May 2015 were collected. Inclusion criteria were body weight <15 kg and available Hb data immediately prior to and after the onset of CPB. The Hb on CPB was predicted according to Fick's principle from the pre-CPB Hb, the prime volume and the patient blood volume. Linear regression analyses and Bland-Altman plots were used to assess the accuracy of the Hb prediction. Different methods to estimate the blood volume were assessed and compared. RESULTS: The initial Hb on CPB correlated well with the predicted Hb (R2=0.87, p<0.001). A Bland-Altman plot revealed little bias at 0.07 g/dL and an area of agreement from -1.35 to 1.48 g/dL. More sophisticated methods of estimating blood volume from lean body mass did not improve the Hb prediction, but rather increased bias. CONCLUSION: Hb prediction is reasonably accurate, with the best result obtained with the simplest method of estimating the blood volume at 80 mL/kg body weight. When deciding for or against blood-free priming, caution is necessary when the predicted Hb lies in a range of ± 2 g/dL around the transfusion trigger.