Ultrasound enhancing agents in cardiovascular imaging: expanding horizons beyond coronary arteries.

From its inception as a two-dimensional snapshot of the beating heart, echocardiography has become an indelible part of cardiovascular diagnostics. The integration of ultrasound enhancing agents (UEAs) marks a pivotal transition, enhancing its diagnostic acumen beyond myocardial perfusion. These agents have refined echocardiography's capacity to visualize complex cardiac anatomy and pathology with unprecedented clarity, especially in non-coronary artery disease contexts. UEAs aid in detailed assessments of myocardial viability, endocardial border delineation in left ventricular opacification, and identification of intracardiac masses. Recent innovations in UEAs, accompanied by advancements in echocardiographic technology, offer clinicians a more nuanced view of cardiac function and blood flow dynamics. This review explores recent developments in these applications and future contemplated studies.

Modeling the influence of bacteria concentration on the mechanical properties of self-healing concrete (SHC) for sustainable bio-concrete structures.

In this research paper, the intelligent learning abilities of the gray wolf optimization (GWO), multi-verse optimization (MVO), moth fly optimization, particle swarm optimization (PSO), and whale optimization algorithm (WOA) metaheuristic techniques and the response surface methodology (RSM) has been studied in the prediction of the mechanical properties of self-healing concrete. Bio-concrete technology stimulated by the concentration of bacteria has been utilized as a sustainable structural concrete for the future of the built environment. This is due to the recovery tendency of the concrete structures after noticeable structural failures. However, it requires a somewhat expensive exercise and technology to create the medium for the growth of the bacteria needed for this self-healing ability. The method of data gathering, analysis and intelligent prediction has been adopted to propose parametric relationships between the bacteria usage and the concrete performance in terms of strength and durability. This makes is cheaper to design self-healing concrete structures based on the optimized mathematical relationships and models proposed from this exercise. The performance of the models was tested by using the coefficient of determination (R2), root mean squared errors, mean absolute errors, mean squared errors, variance accounted for and the coefficient of error. At the end of the prediction protocol and model performance evaluation, it was found that the classified metaheuristic techniques outclassed the RSM due their ability to mimic human and animal genetics of mutation. Furthermore, it can be finally remarked that the GWO outclassed the other methods in predicting the concrete slump (Sl) with R2 of 0.998 and 0.989 for the train and test, respectively, the PSO outclassed the rest in predicting the flexural strength with R2 of 0.989 and 0.937 for train and test, respectively and the MVO outclassed the others in predicting the compressive strength with R2 of 0.998 and 0.958 for train and test, respectively.

Index of Microcirculatory Resistance to predict microvascular obstruction in STEMI: A systematic review and meta-analysis.

BACKGROUND: Microvascular obstruction (MVO) is an independent predictor of adverse cardiac events after ST-elevation myocardial infarction (STEMI). The Index of Microcirculatory Resistance (IMR) may be a useful marker of MVO, which could simplify the care pathway without the need for Cardiac Magnetic Resonance (CMR). We assessed whether the IMR can predict MVO in STEMI patients. METHODS AND RESULTS: We conducted a systematic review and meta-analysis, including articles where invasive IMR was performed post primary percutaneous coronary intervention (PCI) in addition to MVO assessment with cardiac MRI. We searched PubMed, Scopus, Embase, and Cochrane databases from inception until January 2023. Baseline characteristics, coronary physiology and cardiac MRI data were extracted by two independent reviewers. The random-effects model was used to pool the data. Among 15 articles identified, nine articles (n = 728, mean age 61, 81% male) contained IMR data stratified by MVO. Patients with MVO had a mean IMR of 41.2 [95% CI 32.4-50.4], compared to 25.3 [18.3-32.2] for those without. The difference in IMR between those with and without MVO was 15.1 [9.7-20.6]. Meta-regression analyses demonstrated a linear relationship between IMR and TIMI grade (ß = 0.69 [0.13-1.26]), as well as infarct size (ß = 1.18 [0.24-2.11]) or ejection fraction at 6 months (ß = -0.18 [-0.35 to -0.01]). CONCLUSION: In STEMI, patients with MVO had 15-unit higher IMR than those without. IMR also predicts key prognostic endpoints such as infarct size, MVO, and long-term systolic function.

The effect of occlusion location and technique in mechanical thrombectomy for minor stroke.

INTRODUCTION: Endovascular mechanical thrombectomy (MT) is an established treatment for large vessel occlusion strokes with a National Institutes of Health Stroke Scale (NIHSS) score of 6 or higher. Data pertaining to minor strokes, medium, or distal vessel occlusions, and most effective MT technique is limited and controversial. METHODS: A multicenter retrospective study of all patients treated with MT presenting with NIHSS score of 5 or less at 29 comprehensive stroke centers. The cohort was dichotomized based on location of occlusion (proximal vs. distal) and divided based on MT technique (direct aspiration first-pass technique [ADAPT], stent retriever [SR], and primary combined [PC]). Outcomes at discharge and 90 days were compared between proximal and distal occlusion groups, and across MT techniques. RESULTS: The cohort included 759 patients, 34% presented with distal occlusion. Distal occlusions were more likely to present with atrial fibrillation (p = 0.008) and receive IV tPA (p = 0.001). Clinical outcomes at discharge and 90 days were comparable between proximal and distal groups. Compared to SR, patients managed with ADAPT were more likely to have a modified Rankin Scale of 0-2 at discharge and at 90 days (p = 0.024 and p = 0.013). Primary combined compared to ADAPT, prior stroke, multiple passes, older age, and longer procedure time were independently associated with worse clinical outcome, while successful recanalization was positively associated with good clinical outcomes. CONCLUSIONS: Proximal and distal occlusions with low NIHSS have comparable outcomes and safety profiles. While all MT techniques have a similar safety profile, ADAPT was associated with better clinical outcomes at discharge and 90 days.

Association of GSDMD with microvascular-ischemia reperfusion injury after ST-elevation myocardial infarction.

Objectives: Little is known about the clinical prognosis of gasdermin D (GSDMD) in patients with ST-elevation myocardial infarction (STEMI). The purpose of this study was to investigate the association of GSDMD with microvascular injury, infarction size (IS), left ventricular ejection fraction (LVEF), and major adverse cardiac events (MACEs), in STEMI patients with primary percutaneous coronary intervention (pPCI). Methods: We retrospectively analyzed 120 prospectively enrolled STEMI patients (median age 53 years, 80% men) treated with pPCI between 2020 and 2021 who underwent serum GSDMD assessment and cardiac magnetic resonance (CMR) within 48 h post-reperfusion; CMR was also performed at one year follow-up. Results: Microvascular obstruction was observed in 37 patients (31%). GSDMD concentrations ≧ median (13 ng/L) in patients were associated with a higher risk of microvascular obstruction and IMH (46% vs. 19%, P = 0.003; 31% vs. 13%, P = 0.02, respectively), as well as with a lower LVEF both in the acute phase after infarction (35% vs. 54%, P < 0.001) and in the chronic phase (42% vs. 56%, P < 0.001), larger IS in the acute (32% vs. 15%, P < 0.001) and in the chronic phases (26% vs. 11%, P < 0.001), and larger left ventricular volumes (119 ± 20 vs. 98 ± 14, P = 0.003) by CMR. Univariable and multivariable Cox regression analysis results showed that patients with GSDMD concentrations ≧ median (13 ng/L) had a higher incidence of MACE (P < 0.05). Conclusions: High GSDMD concentrations in STEMI patients are associated with microvascular injury (including MVO and IMH), which is a powerful MACE predictor. Nevertheless, the therapeutic implications of this relation need further research.

Effect of Carbon Nanotubes on the Na+ Intercalation Capacity of Binder Free Mn2V2O7-CNTs Electrode: A Structural Investigation.

Improvements in sodium intercalation in sodium cathodes have been debated in recent years. In the present work, we delineate the significant effect of the carbon nanotubes (CNTs) and their weight percent in the intercalation capacity of the binder-free manganese vanadium oxide (MVO)-CNTs composite electrodes. The performance modification of the electrode is discussed taking into account the cathode electrolyte interphase (CEI) layer under optimal performance. We observe an intermittent distribution of the chemical phases on the CEI, formed on these electrodes after several cycles. The bulk and superficial structure of pristine and Na+ cycled electrodes were identified via micro-Raman scattering and Scanning X-ray Photoelectron Microscopy. We show that the inhomogeneous CEI layer distribution strongly depends on the CNTs weight percentage ratio in an electrode nano-composite. The capacity fading of MVO-CNTs appears to be associated with the dissolution of the Mn2O3 phase, leading to electrode deterioration. This effect is particularly observed in electrodes with low weight percentage of the CNTs in which the tubular topology of the CNTs are distorted due to the MVO decoration. These results can deepen the understanding of the CNTs role on the intercalation mechanism and capacity of the electrode, where there are variations in the mass ratio of CNTs and the active material.

Enhanced Drug Delivery for Cardiac Microvascular Obstruction with an Occlusion-Infusion-Catheter.

Microvascular Obstruction (MVO) is a common consequence of acute myocardial infarction. MVO is underdiagnosed and treatment is often nonspecific and ineffective. A multi-scale in-vitro benchtop model was established to investigate drug perfusion in MVO affected microcirculation. The central element of the benchtop model was a fluidic microchip containing channels with diameters between [Formula: see text] and 50 µm representing [Formula: see text] of the microvascular tree fed by the left anterior descending artery (LAD). The outlets of the chip could be closed to mimic MVO. Two methods for intracoronary infusion of pharmacologic agents (simulated by dye) to regions with MVO were investigated using an occlusion-infusion catheter. The first case was a simple, bolus-like infusion into the LAD, whereas the second case consisted of infusion with concomitant proximal occlusion of the LAD phantom with a balloon. Results show that local dye concentration maxima in the chip with MVO were 2.2-3.2 times higher for the case with proximal balloon occlusion than for the conventional infusion method. The cumulated dose could be raised by a factor 4.6-5.2. These results suggest that drug infusion by catheter is more effective if the blood supply to the treated vascular bed is temporarily blocked by a balloon catheter.

Impact of Obesity on Microvascular Obstruction and Area at Risk in Patients After ST-Segment-Elevation Myocardial Infarction: A Magnetic Resonance Imaging Study.

Background: Better survival for overweight and obese patients after ST-segment elevation myocardial infarction (STEMI) has been demonstrated. The association between body mass index (BMI), microvascular obstruction (MVO), and area at risk (AAR) after STEMI was evaluated. Methods: A prospective observational study was performed to enrolled patients undergoing primary percutaneous coronary intervention (pPCI) for STEMI and cardiac magnetic resonance was performed within 5-7 days. Patients were classified as normal weight (18.5 ≤BMI <24.0 kg/m2), overweight (24.0 ≤BMI <28.0 kg/m2), or obese (BMI ≥28 kg/m2). Results: Among 225 patients undergoing pPCI, 67 (30.00%) were normal weight, 113 (50.22%) were overweight, and 45 (20.00%) were obese. BMI ≥28 kg/m2 was significantly associated with less risk of MVO when compared with a normal BMI after multivariable adjustment (overweight: HR 0.29, 95% CI 0.13-0.68, p = 0.004). Compared with normal weight patients, obese and overweight patients tend to have larger hearts (greater left ventricular end-diastolic volume [LVEDV] and left ventricular [LV] mass). In adjusted analysis, increased BMI was significantly associated with a smaller AAR. In addition, obese patients had a smaller AAR (ß = -0.252, 95% CI -20.298- -3.244, p = 0.007) and AAR, % LV mass (ß = -0.331, 95% CI -0.211- -0.062, p < 0.001) than normal weight patients. Conclusion: Obesity (BMI ≥28 kg/m2) is independently associated with lower risks of MVO and a smaller AAR, % LV mass than normal weight patients among subjects undergoing pPCI for STEMI.

Diagnostic performance of cardiac magnetic resonance segmental myocardial strain for detecting microvascular obstruction and late gadolinium enhancement in patients presenting after a ST-elevation myocardial infarction.

Background: Microvascular obstruction (MVO) and Late Gadolinium Enhancement (LGE) assessed in cardiac magnetic resonance (CMR) are associated with adverse outcome in patients with ST-elevation myocardial infarction (STEMI). Our aim was to analyze the diagnostic performance of segmental strain for the detection of MVO and LGE. Methods: Patients with anterior STEMI, who underwent additional CMR were enrolled in this sub-study of the CARE-AMI trial. Using CMR feature tracking (FT) segmental circumferential peak strain (SCS) was measured and the diagnostic performance of SCS to discriminate MVO and LGE was assessed in a derivation and validation cohort. Results: Forty-eight STEMI patients (62 ± 12 years old), 39 (81%) males, who underwent CMR (i.e., mean 3.0 ± 1.5 days) after primary percutaneous coronary intervention (PCI) were included. All patients presented with LGE and in 40 (83%) patients, MVO was additionally present. Segments in all patients were visually classified and 146 (19%) segments showed MVO (i.e., LGE+/MVO+), 308 (40%) segments showed LGE and no MVO (i.e., LGE+/MVO-), and 314 (41%) segments showed no LGE (i.e., LGE-). Diagnostic performance of SCS for detecting MVO segments (i.e., LGE+/MVO+ vs. LGE+/MVO-, and LGE-) showed an AUC = 0.764 and SCS cut-off value was -11.2%, resulting in a sensitivity of 78% and a specificity of 67% with a positive predictive value (PPV) of 30% and a negative predictive value (NPV) of 94% when tested in the validation group. For LGE segments (i.e., LGE+/MVO+ and LGE+/MVO- vs. LGE-) AUC = 0.848 and SCS with a cut-off value of -13.8% yielded to a sensitivity of 76%, specificity of 74%, PPV of 81%, and NPV of 70%. Conclusion: Segmental strain in STEMI patients was associated with good diagnostic performance for detection of MVO+ segments and very good diagnostic performance of LGE+ segments. Segmental strain may be useful as a potential contrast-free surrogate marker to improve early risk stratification in patients after primary PCI.

Association between cine CMR-based radiomics signature and microvascular obstruction in patients with ST-segment elevation myocardial infarction.

Background: In the process of percutaneous coronary intervention (PCI), patients with ST-segment elevation myocardial infarction (STEMI) may receive large doses of the iodine contrast agent. Some adverse events may be aroused if the patients receive the gadolinium agents. We investigate the association between cine cardiac magnetic resonance (CMR)-based radiomics signature and microvascular obstruction (MVO) in patients with STEMI. Methods: A total of 116 STEMI patients who received continuous CMR within 6 days after PCI were retrospectively included in this study. According to the late gadolinium enhancement (LGE) of CMR, the myocardial infarction (MI) was divided into with and without MVO. Radiomic features were extracted from cine CMR images and the least absolute shrinkage and selectionator operator (LASSO) algorithm was used for features selection and radiomic signatures construction. Binary logistic regression was used to assess association between radiomic signatures and MVO with adjusted for baseline clinical characteristics. Results: Of 116 patients with STEMI, MI with MVO was found in 50 patients and MI without MVO was found in 66 patients. LASSO regression selected five radiomics features for radiomics signature construction. Logistic regression revealed that radiomics score, high sensitivity C-reactive protein (hs-CRP) and creatine phosphokinases (CPK) were independent risk factors for MVO with odds ratio (OR) of 4.41 (95% CI: 2.26-9.93), 1.018 (95% CI: 1.006-1.034) and 1.0007 (95% CI: 1.0004-1.0012), respectively. Area under curve (AUC) of receiver operating characteristic (ROC) of radiomics score to predict MVO was 0.75 (95% CI: 0.68-0.85). Conclusions: Cine CMR-based radiomics signature was an independent predictive factor of MVO in patients with STEMI, which showed the potential of this contrast free radiomics signature to be an imaging biomarker for MVO.

Rare Coronary Embolism Secondary to Cardioversion of Atrial Fibrillation.

The diagnosis and management of myocardial infarction with nonobstructive coronary arteries (MINOCA) are difficult due to its variable presentations, different causes, and challenging diagnostic approaches. Cardiac imaging modalities including cardiac magnetic resonance (CMR) are very useful tools for diagnosing and managing MINOCA. Myocardial infarction (MI) can be caused by coronary emboli that can be contributed to atrial fibrillation (AF). Rarely, coronary embolism with resultant MINOCA can occur after direct current cardioversion (DCCV) even in fully anticoagulated patients. We present a rare case of a coronary embolism following DCCV as well as a CMR finding of microvascular obstruction (MVO), which has not previously been reported after DCCV. This case also emphasizes the value of obtaining a CMR for patients with MINOCA.

Effect of Collateral Flow on Catheter-Based Assessment of Cardiac Microvascular Obstruction.

Cardiac microvascular obstruction (MVO) associated with acute myocardial infarction (heart attack) is characterized by partial or complete elimination of perfusion in the myocardial microcirculation. A new catheter-based method (CoFI, Controlled Flow Infusion) has recently been developed to diagnose MVO in the catheterization laboratory during acute therapy of the heart attack. A porcine MVO model demonstrates that CoFI can accurately identify the increased hydraulic resistance of the affected microvascular bed. A benchtop microcirculation model was developed and tuned to reproduce in vivo MVO characteristics. The tuned benchtop model was then used to systematically study the effect of different levels of collateral flow. These experiments showed that measurements obtained in the catheter-based method were adversely affected such that collateral flow may be misinterpreted as MVO. Based on further analysis of the measured data, concepts to mitigate the adverse effects were formulated which allow discrimination between collateral flow and MVO.

An Improved 3D Deep Learning-Based Segmentation of Left Ventricular Myocardial Diseases from Delayed-Enhancement MRI with Inclusion and Classification Prior Information U-Net (ICPIU-Net).

Accurate segmentation of the myocardial scar may supply relevant advancements in predicting and controlling deadly ventricular arrhythmias in subjects with cardiovascular disease. In this paper, we propose the architecture of inclusion and classification of prior information U-Net (ICPIU-Net) to efficiently segment the left ventricle (LV) myocardium, myocardial infarction (MI), and microvascular-obstructed (MVO) tissues from late gadolinium enhancement magnetic resonance (LGE-MR) images. Our approach was developed using two subnets cascaded to first segment the LV cavity and myocardium. Then, we used inclusion and classification constraint networks to improve the resulting segmentation of the diseased regions within the pre-segmented LV myocardium. This network incorporates the inclusion and classification information of the LGE-MRI to maintain topological constraints of pathological areas. In the testing stage, the outputs of each segmentation network obtained with specific estimated parameters from training were fused using the majority voting technique for the final label prediction of each voxel in the LGE-MR image. The proposed method was validated by comparing its results to manual drawings by experts from 50 LGE-MR images. Importantly, compared to various deep learning-based methods participating in the EMIDEC challenge, the results of our approach have a more significant agreement with manual contouring in segmenting myocardial diseases.

Implications of Iron Deficiency in STEMI Patients and in a Murine Model of Myocardial Infarction.

In patients with a first anterior ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention, iron deficiency (ID) was associated with larger infarcts, more extensive microvascular obstruction, and higher frequency of adverse left ventricular remodeling as assessed by cardiac magnetic resonance imaging. In mice, an ID diet reduced the activity of the endothelial nitric oxide synthase/soluble guanylate cyclase/protein kinase G pathway in association with oxidative/nitrosative stress and increased infarct size after transient coronary occlusion. Iron supplementation or administration of an sGC activator before ischemia prevented the effects of the ID diet in mice. Not only iron excess, but also ID, may have deleterious effects in the setting of ischemia and reperfusion.

Impact of age on reperfusion success and long-term prognosis in ST-segment elevation myocardial infarction - A cardiac magnetic resonance imaging study.

BACKGROUND: Coronary collateral circulation and conditioning from remote ischemic coronary territories may protect culprit myocardium in the elderly, and younger STEMI patients could suffer from larger infarcts. We evaluated the impact of age on myocardial salvage and long-term prognosis in a contemporary STEMI cohort. METHODS: Of 1603 included STEMI patients 807 underwent cardiac magnetic resonance. To assess the impact of age on infarct size and left ventricular ejection fraction (LVEF) as well as the composite endpoint of death and re-hospitalization for heart failure we stratified the patients by an age cut-off of 60 years. RESULTS: Younger STEMI patients had smaller final infarcts (10% vs. 12%, P = 0.012) and higher final LVEF (60% vs. 58%, P = 0.042). After adjusting for multiple potential confounders age did not remain significantly associated with infarct size and LVEF. During 4-year follow-up, the composite endpoint occurred less often in the young (3.2% vs. 17.2%; P < 0.001) with a univariate hazard ratio of 5.77 (95% CI, 3.75-8.89; p < 0.001). Event estimates of 4 subgroups (young vs. elderly and infarct size beyond vs. below median) showed a gradual increase in the occurrence of the composite endpoint depending on both age and acute infarct size (log-rank p < 0.001). CONCLUSION: Having a STEMI after entering the seventh decade of life more than quadrupled the risk of future death or re-hospitalization for heart failure. Risk of death and re-hospitalization depended on both advanced age and infarct size, albeit no substantial difference was found in infarct size, LVEF and salvage potential between younger and elderly patients with STEMI.

Association of microRNA-224-3p and microRNA-155-5p expressions with plasma long pentraxin 3 concentration and coronary microvascular obstruction following primary angioplasty for acute ST-segment elevation myocardial infarction.

OBJECTIVE: Pro-inflammatory stimuli induce a variety set of microRNAs (miRs) expression that regulate long pentraxin-3 (PTX3) protein, which associates with a procoagulant state in the endothelial cells. We evaluated, for the first time in human, the association of miR-224-3p and miR-155-5p expressions with plasma PTX3 concentration and coronary microvascular obstruction (MVO) in patients with acute ST-segment elevation myocardial infarction (STEMI) with symptom onset ≤ 12 h and treated by primary angioplasty. Blood samples for miRs and PTX3 measurement were drawn at emergency department presentation, and were measured by TaqMan real-time PCR and human ELISA kit, respectively. RESULTS: Of the 217 patients (median age: 54 years, male: 88%), 130 (60%) had angiographic MVO. Spearman analysis showed no correlation between miR-224-3p and miR-155-5p expressions with plasma PTX3 concentration. After adjustment with sex, age, diabetes mellitus, and plasma PTX3 concentration, miR-224-3p ≥ median group was associated with angiographic MVO (odds ratio, 2.60; 95% confidence interval, 1.24 to 5.44, p = 0.01). This study suggests that miR-224-3p and miR-155-5p expressions did not correlate with plasma PTX3 concentration. However, miR-224-3p expression associates with angiographic MVO following primary angioplasty for STEMI. Future studies are needed to identify the specific gene/protein related with miR-224-3p expression in MVO.

Intravenously delivered mesenchymal stem cells prevent microvascular obstruction formation after myocardial ischemia/reperfusion injury.

Microvascular obstruction (MVO) after primary percutaneous coronary intervention (pPCI) is identified as an independent risk factor for poor prognosis in patients with acute myocardial infarction (AMI). The inflammatory response induced by ischemia and reperfusion (I/R) injury is considered one of the main mechanisms of MVO. Mesenchymal stem cells (MSCs) are a unique stromal cell type that confers an immunomodulatory effect in cardiac disease. The present study aimed to investigate whether immediate intravenous delivery of MSCs could be used as a potential therapeutic method to attenuate MVO formation. A cardiac catheterization-induced porcine model of myocardial I/R injury was established, and allograft MSCs were immediately delivered intravenously. Cardiac magnetic resonance (CMR) imaging was performed on days 2 and 7 after the operation to determine the infarct area, MVO, and cardiac function. The pigs with allograft MSCs showed decreased MVO and infarct size, as well as an improved left ventricular ejection fraction (LVEF). Histological analysis revealed decreased myocyte area, fibrosis, and inflammatory cell infiltration in the peri-infarct zone of pigs with allograft MSCs. Moreover, the concentrations of interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and C-reactive protein (CRP) in the serum were reduced in the allograft MSC group compared to the control group. Flow cytometry indicated decreased natural killer (NK) cells in the peripheral blood and ischemic heart tissue in the pigs with allograft MSCs. In summary, allograft MSCs delivered intravenously and immediately after myocardial I/R injury can attenuate MVO formation in a porcine model through a decline in the number of NK cells in the myocardium.

A Challenging and Unexpected Case of MINOCA Using Multimodality Imaging.

We describe a challenging case of a patient with MINOCA due to isolated right ventricular myocardial infarction with microvascular obstruction identified on cardiac magnetic resonance imaging. This case highlights that even a comprehensive, guideline-based assessment of these patients can initially fail to detect the underlying pathology. (Level of Difficulty: Beginner.).

Ablation of Incessant Premature Ventricular Complex Through Retrograde Transvenous Ethanol Infusion.

Ethanol infusion has been used for the treatment of ventricular arrhythmia. We describe a case of ethanol infusion through the coronary sinus venous network to treat refractory epicardial premature ventricular complexes. The premature ventricular complexes were initially successfully suppressed but recurred after resolution of the myocardial edema. (Level of Difficulty: Intermediate.).

Intracranial pressure-based barbiturate coma treatment in children with refractory intracranial hypertension due to traumatic brain injury.

OBJECTIVE: Refractory intracranial pressure (ICP) hypertension following traumatic brain injury (TBI) is a severe condition that requires potentially harmful treatment strategies such as barbiturate coma. However, the use of barbiturates may be restricted due to concerns about inducing multiorgan system complications related to the therapy. The purpose of this study was to evaluate the outcome and occurrence of treatment-related complications to barbiturate coma treatment in children with refractory intracranial hypertension (RICH) due to TBI in a modern multimodality neurointensive care unit (NICU). METHODS: The authors conducted a retrospective cohort study of 21 children ≤ 16 years old who were treated in their NICU between 2005 and 2015 with barbiturate coma for RICH following TBI. Demographic and clinical data were acquired from patient records and physiological data from digital monitoring system files. RESULTS: The median age of these 21 children was 14 years (range 2-16 years) and at admission the median Glasgow Coma Scale score was 7 (range 4-8). Barbiturate coma treatment was added due to RICH at a median of 46 hours from trauma and had a median duration of 107 hours. The onset of barbiturate coma resulted in lower ICP values, lower pulse amplitudes on the ICP curve, and decreased amount of A-waves. No major disturbances in blood gases, liver and kidney function, or secondary insults were observed during this period. Outcome 1 year later revealed a median Glasgow Outcome Scale score of 5 (good recovery), however on the King's Outcome Scale for Childhood Head Injury, the median was 4a (moderate disability). CONCLUSIONS: The results of this study indicate that barbiturate coma, when used in a modern NICU, is an effective means of lowering ICP without causing concomitant severe side effects in children with RICH and was compatible with good long-term outcome.