Cardiovascular magnetic resonance features of mechanical dyssynchrony in patients with left bundle branch block

Patients with left bundle branch block (LBBB) can exhibit mechanical dyssynchrony which may contribute to heart failure; such patients may benefit from cardiac resynchronization treatment (CRT). While cardiac magnetic resonance imaging (CMR) has become a common part of heart failure work-up, CMR features of mechanical dyssynchrony in patients with LBBB have not been well characterized. This study aims to investigate the potential of CMR to characterize mechanical features of LBBB. CMR examinations from 43 patients with LBBB on their electrocardiogram, but without significant focal structural abnormalities, and from 43 age- and gender-matched normal controls were retrospectively reviewed. The following mechanical features of LBBB were evaluated: septal flash (SF), apical rocking (AR), delayed aortic valve opening measured relative to both end-diastole (AVO_ED) and pulmonic valve opening (AVO_PVO), delayed left-ventricular (LV) free-wall contraction, and curvatures of the septum and LV free-wall. Septal displacement curves were also generated, using feature-tracking techniques. The echocardiographic findings of LBBB were also reviewed in those subjects for whom they were available. LBBB was significantly associated with the presence of SF and AR; within the LBBB group, 79?% had SF and 65?% had AR. Delayed AVO_ED, AVO_PVO, and delayed LV free-wall contraction were significantly associated with LBBB. AVO_ED and AVO_PVO positively correlated with QRS duration and negatively correlated with ejection fraction. Hearts with electrocardiographic evidence of LBBB showed lower septal-to-LV free-wall curvature ratios at end-diastole compared to normal controls. CMR can be used to identify and evaluate mechanical dyssynchrony in patients with LBBB. None of the normal controls showed the mechanical features associated with LBBB. Moreover, not all patients with LBBB showed the same degree of mechanical dyssynchrony, which could have implications for CRT.     

Are changes in the extent of left ventricular dyssynchrony as assessed by speckle tracking associated with response to cardiac resynchronization therapy?

Echocardiographic assessment of left ventricular (LV) dyssynchrony is used to predict response to cardiac resynchronization therapy (CRT). However, the association between reduction in the extent of speckle tracking based LV-dyssynchrony and echocardiographic response to CRT has not been explored yet. The aim of this study was to assess the changes in the extent of LV dyssynchrony as a result of CRT and its association with echocardiographic response to CRT in a large consecutive series of patients. We studied 138 patients with standard CRT indication. Time-based speckle tracking longitudinal strain (maximal delay between 6-segments in 4-chamber view) was performed to assess LV-dyssynchrony at baseline and after a mean follow-up of 22 ± 8 months. Echocardiographic CRT response was defined as a reduction in LV end-systolic volume ≥15 %. Mean age was 68 ± 8 years (30 % female). Mean LV ejection fraction (LVEF) was 26 ± 7 %. Ninety six patients (70 %) were classified as echocardiographic responders. In the total study group, LV-dyssynchrony decreased from 196 ± 89 ms at baseline to 180 ± 105 ms during follow-up, P = 0.01. Of note, in responders there was a pronounced reduction in LV dyssynchrony (198 ± 88 ms at baseline vs 154 ± 50 ms after CRT, P < 0.001), whereas in non-responders there was a significant increase (191 ± 92 ms at baseline vs 243 ± 160 ms after CRT, P = 0.04). After multivariate analysis, decreased in LV-dyssynchrony, wider QRS duration and non-ischemic etiology were independently and significantly associated with CRT response. Changes in the extent of LV dyssynchrony as measured by speckle tracking after CRT are independently associated with response to CRT.     

Systolic heart failure and cardiac resynchronization therapy: a focus on diastole

Conflicting data exist about the effects of cardiac resynchronization therapy (CRT) on diastolic function (DF). Aim of the study was to assess if and how CRT affects DF in systolic heart failure patients. We also investigated potential relations between CRT-induced left ventricular changes and the composite clinical endpoint of progressive heart failure and cardiac death over 3 years follow-up. 119 CRT patients underwent clinical evaluation and echocardiography before CRT and 4 months later. DF was quantified by transmitral velocities [E/A waves, deceleration time (DT), E/DT], early diastolic mitral annulus velocity (E′), E/E′ ratio and 2-D speckle tracking strain rate during isovolumetric relaxation (IVR, SRivr). End-diastolic pressure–volume relationship (EDPVR) was also assessed noninvasively using a single-beat method. Overall stiffness was quantified by ventricular stiffness (K_lv) normalized to end-diastolic volume (EDV). New York Heart Association class improved at 4 months (from 2.7 ± 0.7 to 1.9 ± 0.6, p < 0.001) as did ventricular filling (E/DT from 0.48 ± 0.29 to 0.39 ± 0.31 cm/s², p = 0.01). In contrast, relaxation (E′, SRivr) and filling pressures (E/E′, E/SRivr) did not change. Slope of EDPVR did not change with CRT. Such finding, together with an unmodified Klv/EDV and a 7 ± 18 % reduction in EDV (p = 0.001), suggested reverse remodelling towards a smaller equilibrium volume. Finally, end-systolic LV volume decreased from 147 ± 59 to 125 ± 52 ml and ejection fraction increased from 0.26 ± 0.07 to 0.32 ± 0.09 (both p < 0.001). Using a Cox regression model we found that only changes (Δ) in diastolic, but not systolic indexes, correlated with the composite clinical endpoint, with increments in ΔEDV20 and ΔE/DT, single or combined, greatly increasing risk of heart failure and/or cardiac death (p = 0.003). Ventricular reverse remodelling, together with improvement in ventricular filling, rather than improvements of systolic function, predict clinical prognosis long-term post-CRT.     

Mechanical dyssynchrony alters left ventricular flow energetics in failing hearts with LBBB: a 4D flow CMR pilot study

The impact of left bundle branch block (LBBB) related mechanical dyssynchrony on left ventricular (LV) diastolic function remains unclear. 4D flow cardiovascular magnetic resonance (CMR) has provided reliable markers of LV dysfunction: reduced volume and kinetic energy (KE) of the portion of LV inflow which passes directly to outflow (Direct Flow) has been demonstrated in failing hearts compared to normal hearts. We sought to investigate the impact of mechanical dyssynchrony on diastolic function by comparing 4D flow in myopathic LVs with and without LBBB. CMR data were acquired at 3 T in 22 heart failure patients; 11 with LBBB and 11 without LBBB matched according to several demographic and clinical parameters. An established 4D flow analysis method was used to separate the LV end-diastolic (ED) volume into functional flow components based on the blood’s timing and route through the heart cavities. While the Direct Flow volume was not different between the groups, the KE possessed at ED was lower in LBBB patients (P?=?0.018). Direct Flow entering the LV during early diastolic filling possessed less KE at ED in LBBB patients compared to non-LBBB patients, whereas no intergroup difference was observed during late filling. Pre-systolic KE of LV Direct Flow was reduced in patients with LBBB compared to matched patients with normal conduction. These intriguing findings propose that 4D flow specific measures can serve as markers of LV mechanical dyssynchrony in heart failure patients, and could possibly be investigated as predictors of response to cardiac resynchronization therapy.     

Autoregulation monitoring and outcome prediction in neurocritical care patients: Does one index fit all?

Indexes PRx and Mx have been formerly introduced to assess cerebral autoregulation and have been shown to be associated with 3-month clinical outcome. In a mixed cohort of neurocritical care patients, we retrospectively investigated the impact of selected clinical characteristics on this association. Forty-one patients (18–77 years) with severe traumatic (TBI, N = 20) and non-traumatic (N = 21) brain injuries were studied. Cerebral blood flow velocity, arterial blood pressure and intracranial pressure were repeatedly recorded during 1-h periods. Calculated PRx and Mx were correlated with 3-month clinical outcome score of modified Rankin Scale (mRS) in different subgroups with specific clinical characteristics. Both PRx and Mx correlated significantly with outcome (PRx: r = 0.38, p < 0.05; AUC = 0.64, n.s./Mx: r = 0.48, p < 0.005; AUC = 0.80, p < 0.005) in the overall group, and in patients with hemicraniectomy (N = 17; PRx: r = 0.73, p < 0.001; AUC = 0.89, p < 0.01/Mx: r = 0.69, p < 0.005; AUC = 0.87, p < 0.05). Mx, not PRx, correlated significantly with mRS in patients with heart failure (N = 17; r = 0.69, p < 0.005; AUC = 0.92, p < 0.005), and in non-traumatic patients (r = 0.49, p < 0.05; AUC = 0.79, p < 0.05). PRx, not Mx, correlated significantly with mRS in TBI patients (r = 0.63, p < 0.01; AUC = 0.89, p < 0.01). Both indexes did not correlate with mRS in diabetes patients (N = 15), PRx failed in hypocapnic patients (N = 26). Both PRx and Mx were significantly associated with 3-month clinical outcome, even in patients with hemicraniectomy. PRx was more appropriate for TBI patients, while Mx was better suited for non-traumatic patients and patients with heart failure. Prognostic values of indexes were affected by diabetes (both Mx and PRx) and hypocapnia (PRx only).     

Impact of right ventricular dyssynchrony on left ventricular performance in patients with pulmonary hypertension

Pulmonary hypertension has been associated with right ventricular (RV) dyssynchrony which may induce left ventricular (LV) dysfunction and dyssynchrony through ventricular interdependence. The present study evaluated the influence of RV dyssynchrony on LV performance in patients with pulmonary hypertension. One hundred and seven patients with pulmonary hypertension (age 63 ± 14 years, systolic pulmonary arterial pressure 60 ± 19 mmHg) and LV ejection fraction (EF) >35 % were evaluated. Ventricular dyssynchrony was assessed with speckle tracking echocardiography and defined as the standard deviation of the time to peak longitudinal strain of six segments of the RV (RV-SD) and the LV (LV-SD) in the apical 4-chamber view. Mean RV-SD and LV-SD assessed with longitudinal strain speckle tracking echocardiography were 51 ± 28 and 47 ± 21 ms, respectively. The patient population was divided according to the median RV-SD value of 49 ms. Patients with RV-SD ≥49 ms had significantly worse NYHA functional class (2.7 ± 0.7 vs. 2.3 ± 0.7, p = 0.004), RV function (tricuspid annular plane systolic excursion: 16 ± 4 vs. 19 ± 4 mm, p < 0.001), LVEF (50 ± 10 vs. 55 ± 8 %, p = 0.001), and larger LV-SD (57 ± 18 vs. 36 ± 18 ms, p < 0.001). RV-SD significantly correlated with LV-SD (r = 0.55, p < 0.001) and LVEF (r = ?0.23, p = 0.02). Multiple linear regression analysis showed an independent association between RV-SD and LV-SD (β = 0.35, 95 %CI 0.21–0.49, p < 0.001). RV dyssynchrony is significantly associated with LV dyssynchrony and reduced LVEF in patients with pulmonary hypertension.     

Utility of cardiac magnetic resonance imaging, echocardiography and electrocardiography for the prediction of clinical response and long-term survival following cardiac resynchronisation therapy

Cardiac resynchronisation therapy (CRT) can reduce symptoms, hospitalisations, and mortality in patients with severe left ventricular (LV) systolic dysfunction and electro-mechanical dyssynchrony. Unfortunately, approximately 30 % of eligible patients fail to respond to CRT. This study prospectively compared electrocardiography (ECG), echocardiography, and cardiac magnetic resonance (CMR) imaging for the prediction of response to CRT. We performed ECG, echocardiography and CMR on 46 patients prior to planned CRT implantation. Patients were divided into predicted responder and non-responder groups using previously described criteria for each modality. Changes in indicators of CRT response were recorded 6 months post-implantation, and later for transplant-free survival. Less dyspnoea, lower levels of N-terminal pro-brain natriuretic peptide, more LV reverse remodelling, and longer transplant-free survival were observed in predicted responders compared to predicted non-responders using each of the three modalities (p < 0.05 for each comparison). Additionally, for patients with QRS duration <150 ms and/or non-left bundle branch block (non-LBBB) QRS morphology, CMR predicted both clinical response and improved longer term transplant-free survival (80 % transplant-free survival in predicted responders vs. 20 % in predicted non-responders, p = 0.04). ECG and cardiac imaging techniques predict improvements in markers of response following CRT with similar accuracy. However, for CRT candidates with shorter, non-LBBB QRS complexes, a subgroup known to derive less benefit from CRT, CMR may predict those who are more likely to gain both symptomatic and survival benefits.     

超声心动图用于诊断和再同步化治疗左束支传导阻滞进展

超声心动图可检测左束支传导阻滞（LBBB）所致心肌收缩功能及心肌运动不同步,指导筛选心脏再同步化治疗（CRT）适应证。本文对超声心动图在诊断LBBB和筛选CRT适应证中的应用进展进行综述。     

Not left ventricular lead position,but the extent of immediate asynchrony reduction predicts long-term response to cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an effective treatment for a large subgroup of chronic heart failure patients. Various attempts to improve the high non-responder rate of 30 % by preoperative asynchrony assessment have failed. We hypothesized that superior response to CRT is correlated with greater acute reduction of asynchrony and that a concordant left ventricular (LV) lead is beneficial compared to a discordant lead. Hundred and eight consecutive CRT patients from our center were prospectively included. Clinical status and asynchrony parameters were assessed before, 1 day and 6 months after CRT implantation. Super-response was defined as an increase of the LV ejection fraction by ≥15 % and a decrease in LV end systolic volume (LVESV) by ≥30 %. When the criteria for super-response were not met, average response was given with a decrease of baseline LVESV ≥15 %. Sixty eight patients were classified as responders (63 %). Comparing super- (n = 19) and average (n = 49) responders, we found that greater acute reduction of LV asynchrony (change of asynchronous segments under CRT: ?1.3 vs. ?0.4, p < 0.05; decrease of LV intraventricular delay: ?34 ms vs. ?16 ms, p < 0.05) is associated with superior reverse remodeling after 6 months. Importantly, asynchrony parameters of super-, average and non-responders were almost identical at baseline. A concordant LV lead (n = 63) was not associated with improved LV reverse remodeling compared to a discordant lead (n = 28): LVEF: +8.6 % vs. +7.8 %, p = 0.91; LVESV: ?30.5 ml vs. ?23.8 mL, p = 0.84. A greater immediate reduction of LV asynchrony predicts superior response. Preoperative asynchrony parameters do not correlate with outcome. A concordant LV lead is not superior to a discordant lead.     

Extraordinarily favorable left ventricular reverse remodeling through long-term cardiac resynchronization: super-response to cardiac resynchronization

Background: Some chronic heart failure (CHF) patients show remarkable improvement in left ventricular (LV) remodeling after cardiac resynchronization therapy (CRT), for unclear reasons. This study aimed at identifying predictors of an extraordinarily favorable response to CRT. Methods: We studied 136 CRT patients (104 men, median 66 years, QRS 162 ms, left ventricular ejection fraction 24 ± 7%, 70% coronary disease, all left bundle branch block [LBBB]). We measured LV end diastolic diameter (LVEDD) before and after long‐term (9.4 ± 6.3 months) CRT. At baseline, LV pre‐ejection interval (LVPEI), interventricular mechanical delay (IVMD), LV dyssynchrony (standard deviation of electromechanical delays [SDEMD] in eight LV segments), exercise capacity (pVO₂), and ventilatory efficiency (VE/VCO₂) were assessed. Patients with a LVEDD reduction beyond the 80th percentile (high responders [HR]) were compared to low responders (LR). Results: In the HR group (n = 22), LVEDD was reduced from 71 to 52 mm (LR 64–61 mm, P < 0.001). HR had predominantly nonischemic heart disease (HR: 72%, LR: 44%, P = 0.019), tended to have a wider QRS (HR: 178 ms, LR: 162 ms, P = 0.066), had a longer LVPEI (HR: 179 ms, LR: 155 ms, P = 0.004), wider IVMD (HR: 60 ms, LR 48 ms, P = 0.05), larger LVEDD (P = 0.002), higher SDEMD (HR: 69 ms, LR: 46 ms, P = 0.044), but higher pVO₂ (HR: 17.5 mL/min/kg, LR: 13.5 mL/kg/min, P = 0.025) and lower VE/VCO₂ (HR: 31, LR: 35, P = 0.043), all compared to LR patients. Conclusion: Extraordinarily favorable reverse LV remodeling through CRT in CHF and LBBB appears to require a particularly dilated LV due to nonischemic heart disease with pronounced electromechanical alteration, but with a fairly preserved functional capacity before CRT. (PACE 2012;XX:1–7)     

Patient and Health Care Provider Responses from a Prospective,Double-Blind,Randomized Controlled Trial Comparing Vapocoolant Spray versus Placebo Spray in Adults Undergoing Venipuncture in the Emergency Department

Background: Painful medical procedures are common. Topical anesthetics are easily applied, rapid onset, inexpensive, and avoid injection pain and needlestick injury. The aims of this study, using patient and health care provider questionnaires, were to answer the following questions: (1) Does vapocoolant spray decrease venipuncture pain? (2) Would patients be satisfied with and use a vapocoolant spray in the future? (3) Would providers be satisfied with and use a vapocoolant spray in the future? Design: Adults (18-80 years) in a hospital emergency department (ED) were randomly assigned to sterile water placebo spray (S) (N = 50) or vapocoolant spray (V) (N = 50) before venipuncture. Questionnaires were completed by patients undergoing venipuncture (N = 100) and the health care providers (N = 100) who performed the venipuncture (total questionnaires = 200) as part of a prospective, double-blind, randomized controlled trial comparing the efficacy and safety of vapocoolant spray compared with placebo spray in patients undergoing venipuncture in the ED. Results: Patient and venipuncture variables were not significantly different for the two groups (S vs. V). Responses to the questionnaires were significantly different for the S versus V groups for both the patients and the health care providers. Patient questionnaires: Did you have less pain with spray? S 14%, V 76% (p < .001). Compared with previous blood draws, the spray was much more painful/more painful: S 10%, V 6%; same: S 76%, V 16%; less painful/much less painful: S 14%, V 78% (p < .001). How satisfied were you with the spray? Satisfied/very satisfied: S 20%, V 74% (p < .001). Would you use this spray in future? Yes S 20%, V 80% (p < .001). Provider results: The patient had less pain with the use of the spray: S 14%, V 78% (p < .001). How satisfied were you with the use of the spray? Satisfied/very satisfied: S 12%, V 82% (p < .001). Would you use this spray in the future? Yes S 24%, V 84% (p < .001). Conclusions: The use of a vapocoolant spray in adult ED patients undergoing venipuncture significantly decreased venipuncture pain, was associated with high patient and provider satisfaction, and both patients and providers would use a vapocoolant spray in the future for venipuncture and other painful procedures.     

Negative Automatic Evaluation and Better Recognition of Bodily Symptom Words in College Students with Elevated Health Anxiety

This study explored whether better recognition of symptom words is associated with stronger negative automatic evaluations of these words. We compared participants with health anxiety (HA; N = 27) to dysphoric (N = 29) and to non-health-anxious and non-dysphoric control participants (N = 28) in the Implicit Association Test (IAT) and in a word recognition task using health-threat-related, negative emotional, and neutral control words. Participants with HA made significantly more mistakes on the IAT than both other groups, in pairing the evaluation “harmless” with specific “symptoms” (p = .02, η² = .10). Additionally, recognition performance was positively related to the IAT evaluation bias. The findings suggest that persons with HA automatically interpret symptoms as being more dangerous than the others saw them. This evaluation bias might explain the facilitation of access to symptom information in working memory that underlies cognitive biases observed in HA.     

Rate-dependent aberrancy and cardiac resynchronization therapy

Left bundle branch block (LBBB) can result in significant dyssynchrony in left ventricular (LV) contraction, ultimately leading to cardiac remodeling. LBBB can be rate dependent and may appear with LV systolic dysfunction. Cardiac resynchronization therapy (CRT) has been demonstrated to improve hemodynamics as well as clinical symptoms in patients with LBBB. We describe the case of a 57-year-old man who underwent CRT implantation due to exertional dyspnea, rate-dependent LBBB, and impaired left LV systolic function.     

Acoustic structure quantification (ASQ): a new tool in sonographic examination of liver lesions in hepatic alveolar echinococcosis

Purpose

Qualitative and quantitative acoustic structure quantification (ASQ) is a new, noninvasive sonographic imaging method based on B-mode. This prospective clinical pilot study aims to answer the question whether delineation and measurement of liver lesions in hepatic alveolar echinococcosis (HAE) can be improved by ASQ. Furthermore, this is the first pilot study to explore how ASQ parameters in HAE lesions develop.

Methods

A total of 24 patients (male = 13/female = 11, mean age = 52 years (16–85), mean disease duration = 68 months (1–334)) with HAE were examined with ASQ using a Toshiba Aplio 500 unit. ASQ parameters were measured in HAE liver lesions and in adjacent non-tumor parenchyma. Quantitative analysis was performed offline using ASQ quantification software.

Results

Subjectively parasitic tumors in HAE appear more prominent in color-coded ASQ imaging, but the size of lesions measured in ASQ mode does not differ from size measurements in B-mode. Median focal disturbance ratio (FD ratio) in lesions was 3 (0.1–3), compared with 0.5 (0.1–1.8) in surrounding liver parenchyma (p < 0.0001). Statistical comparison of other ASQ parameters (mode, average, standard deviation) shows results that are similarly significant with p values between p < 0.0001 and p < 0.0018.

Conclusion

ASQ is a promising sonographic method for examination and quantification of structural changes of liver parenchyma in HAE lesions.     

Acute improvement of cardiac efficiency measured by 11C-acetate PET after cardiac resynchronization therapy and clinical outcome

The purpose of this study was to examine the usefulness of ¹¹C-acetate positron emission tomography (PET) for assessing the efficacy of cardiac resynchronization therapy (CRT). Enrolled in this study were 20 patients with severe heart failure. All patients underwent 11C-acetate PET within 1 week after CRT. The oxygen consumption was measured by the monoexponential clearance rate of 11C-acetate (K_mono) for both CRT-off and -on. Cardiac efficiency (CE) was determined using the concept of the work metabolic index (WMI). WMI was calculated as WMI = (stroke volume index) × (systolic blood pressure) × (heart rate)/K_mono. The patients were divided into two groups: 14 patients with improved CE (from 5.27 ± 0.91 to 6.77 ± 1.12) and 6 patients with deteriorated CE (from 5.35 ± 0.92 to 4.86 ± 0.84) by CRT-on. K_mono decreased from 0.053 ± 0.006 to 0.046 ± 0.003 by CRT-on in the improved CE group (p = 0.028), but increased from 0.049 ± 0.006 to 0.050 ± 0.006 in the deteriorated-CE group (p = 0.036). Stroke volume index, systolic blood pressure, and heart rate did not change by CRT-on for either group. At the one-year follow-up, there were significantly higher rates of major cardiac adverse events in the deteriorated-CE group than in the improved-CE group (p = 0.032). Therefore, the improvement of CE, as assessed by 11C-acetate PET in the early period after CRT, is produced by the decrease in oxygen consumption in patients showing good responses to CRT. The decrease in oxygen consumption in the early period after CRT is thus a useful marker for predicting a good clinical outcome after CRT.     

Assessment of the inflammatory effect of low-dose oxygen in mechanically ventilated patients

Purpose

Although low doses of oxygen (FiO₂ <0.50) are considered nontoxic, recent studies have shown that even lower doses increase pulmonary inflammatory mediators. We aimed to evaluate the acute effects of reducing FiO₂ on pulmonary inflammation in mechanically ventilated patients without respiratory failure.

Methods

This study was a prospective, single-center crossover study in a medical/surgical intensive care unit at a university hospital. Hemodynamically stable patients under mechanical ventilation for >24 h without severe respiratory failure (PaO₂/FiO₂ >250). A basal FiO₂ of 0.40 was reduced to 0.21 provided SpO₂ remained higher than 90 %. Patients who could not tolerate the reduction in FiO₂ to 0.21 were excluded.

Results

We screened 40 patients, but only 28 (70 %) tolerated FiO₂ 0.21. We measured common clinical variables and inflammatory mediators in plasma and in exhaled breath condensate (EBC) at the end of three 4-h periods: (1) basal (FiO₂ 0.40), (2) after FiO₂ reduction to 0.21, and (3) after returning FiO₂ 0.40. We used one-way ANOVA for repeated measurements with FiO₂ as the grouping variable. Median values of inflammatory mediators in EBC showed nonsignificant changes among the three periods: NO₂ + NO₃ 17.1, 14.1 and 11.0 μmol/L (p = 0.2), and 8-isoprostane 4.4, 8.2 and 5.3 pg/ml (p = 0.6) for the three periods, respectively. Plasma levels also showed nonsignificant changes during the period of the study: NO₂ + NO₃ 12.6, 16.3 and 15.0 μmol/L (p = 0.9), TNFα 13.5, 18.0 and 14.5 pg/ml (p = 0.8), IL-4 12.9, 18.7 and 23.9 pg/ml (p = 0.1), IL-6 50.9, 35.1 and 28.3 pg/ml (p = 0.6), and IL-10 15.2, 22.2 and 22.2 pg/ml (p = 0.7) for the three periods, respectively.

Conclusion

FiO₂ 0.40 in mechanically ventilated patients without severe respiratory failure did not increase systemic or pulmonary inflammation.     

Impact of white blood cell count on myocardial salvage,infarct size,and clinical outcomes in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: a magnetic resonance imaging study

We sought to determine the relationship between white blood cell count (WBCc) and infarct size assessed by cardiovascular magnetic resonance imaging (CMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). In 198 patients undergoing primary PCI for STEMI, WBCc was measured upon arrival and CMR was performed a median of 7 days after the index event. Infarct size was measured on delayed enhancement imaging and the area at risk (AAR) was quantified on T2-weighted images. Baseline characteristics were not significantly different between the high WBCc group (>11,000/mm³, n = 91) and low WBCc group (≤11,000/mm³, n = 107). The median infarct size was larger in the high WBCc group than in the low WBCc group [22.0 % (16.7–33.9) vs. 14.7 % (8.5–24.7), p < 0.01]. Compared with the low WBCc group, the high WBCc group had a greater extent of AAR and a smaller myocardial salvage index [MSI = (AAR?infarct size)/AAR × 100]. The major adverse cardiovascular events (MACE) including cardiac death, nonfatal reinfarction, and rehospitalization for congestive heart failure at 12-month occurred more frequently in the high WBCc group (12.1 vs. 0.9 %, p < 0.01). In multivariate analysis, high WBCc significantly increased the risk of a large infarct (OR 3.04 95 % CI 1.65–5.61, p < 0.01), a low MSI (OR 2.08, 95 % CI 1.13–3.86, p = 0.02), and 1-year MACE (OR 16.0, 95 % CI 1.89–134.5, p = 0.01). In patients undergoing primary PCI for STEMI, an elevated baseline WBCc is associated with less salvaged myocardium, larger infarct size and poorer clinical outcomes.     

Reliability,validity and minimal detectable change of the Mini-BESTest in Greek participants with chronic stroke

Objectives: This study aimed to investigate the psychometric characteristics of reliability, validity and ability to detect change of a newly developed balance assessment tool, the Mini-BESTest, in Greek patients with stroke. Design: A prospective, observational design study with test-retest measures was conducted. Methods: A convenience sample of 21 Greek patients with chronic stroke (14 male, 7 female; age of 63 ± 16 years) was recruited. Two independent examiners administered the scale, for the inter-rater reliability, twice within 10 days for the test-retest reliability. Bland Altman Analysis for repeated measures assessed the absolute reliability and the Standard Error of Measurement (SEM) and the Minimum Detectable Change at 95% confidence interval (MDC_95%) were established. The Greek Mini-BESTest (Mini-BESTest_GR) was correlated with the Greek Berg Balance Scale (BBS_GR) for assessing the concurrent validity and with the Timed Up and Go (TUG), the Functional Reach Test (FRT) and the Greek Falls Efficacy Scale-International (FES-I_GR) for the convergent validity. Results: The Mini-BESTestGR demonstrated excellent inter-rater reliability (ICC (95%CI) = 0.997 (0.995–0.999, SEM = 0.46) with the scores of two raters within the limits of agreement (mean_dif = ?0.143 ± 0.727, p > 0.05) and test-retest reliability (ICC (95%CI) = 0.966 (0.926–0.988), SEM = 1.53). Additionally, the Mini-BESTest_GR yielded very strong to moderate correlations with BBS_GR (r = 0.924, p < 0.001), TUG (r = ?0.823, p < 0.001), FES-I_GR (r = ?0.734, p < 0.001) and FRT (r = 0.689, p < 0.001). MDC₉₅ was 4.25 points. Conclusion: The exceptionally high reliability and the equally good validity of the Mini-BESTest_GR, strongly support its utility in Greek people with chronic stroke. Its ability to identify clinically meaningful changes and falls risk need further investigation.     

Serial ultrasound evaluation of intramyocardial strain after reperfused myocardial infarction reveals that remote zone dyssynchrony develops in concert with left ventricular remodeling

This study noninvasively evaluated the development of left ventricular (LV) dyssynchrony following reperfused myocardial infarction (MI) in mice using an ultrasonic speckle-tracking method. Eight C57BL/6J mice were assessed by high-resolution echocardiography at baseline and at eight time-points following MI. Images were acquired at 1mm elevational intervals encompassing the entire LV to determine chamber volumes and radial strain. Receiver-operating characteristic (ROC) analysis of regional radial strain was used to segment the three-dimensional (3-D) LV into infarct, adjacent and remote zones. This in vivo segmentation was correlated to histologic infarct size (R = 0.89, p < 0.01) in a short-axis, slice-by-slice comparison. The onset of dyssynchrony during LV remodeling was assessed by standard deviation of time to peak radial strain in the infarct, adjacent and remote zones. It was discovered that the form of LV dyssynchrony that develops in the remote zone late after MI does so in concert with the progression of LV remodeling (R = 0.70, p < 0.05).