Diagnosis of left ventricular diastolic dysfunction in the setting of acute changes in loading conditions

Cardiopulmonary interactions-which monitoring tools to use?

Heart-lung interactions occur due to the mechanical influence of intrathoracic pressure and lung volume changes on cardiac and circulatory function. These interactions manifest as respiratory fluctuations in venous, pulmonary, and arterial pressures, potentially affecting stroke volume. In the context of functional hemodynamic monitoring, pulse or stroke volume variation (pulse pressure variation or stroke volume variability) are commonly employed to assess volume or preload responsiveness. However, correct interpretation of these parameters requires a comprehensive understanding of the physiological factors that determine pulse pressure and stroke volume. These factors include pleural pressure, venous return, pulmonary vessel function, lung mechanics, gas exchange, and specific cardiac factors. A comprehensive knowledge of heart-lung physiology is vital to avoid clinical misjudgments, particularly in cases of right ventricular (RV) failure or diastolic dysfunction. Therefore, when selecting monitoring devices or technologies, these factors must be considered. Invasive arterial pressure measurements of variations in breath-to-breath pressure swings are commonly used to monitor heart-lung interactions. Echocardiography or pulmonary artery catheters are valuable tools for differentiating preload responsiveness from right ventricular failure, while changes in diastolic function should be assessed alongside alterations in airway or pleural pressure, which can be approximated by esophageal pressure. In complex clinical scenarios like ARDS, combined forms of shock or right heart failure, additional information on gas exchange and pulmonary mechanics aids in the interpretation of heart-lung interactions. This review aims to describe monitoring techniques that provide clinicians with an integrative understanding of a patient's condition, enabling accurate assessment and patient care.

Sepsis-Induced myocardial dysfunction: heterogeneity of functional effects and clinical significance

Sepsis is a life-threatening disease state characterized by organ dysfunction and a dysregulated response to infection. The heart is one of the many organs affected by sepsis, in an entity termed sepsis-induced cardiomyopathy. This was initially used to describe a reversible depression in ejection fraction with ventricular dilation but advances in echocardiography and introduction of new techniques such as speckle tracking have led to descriptions of other common abnormalities in cardiac function associated with sepsis. This includes not only depression of systolic function, but also supranormal ejection fraction, diastolic dysfunction, and right ventricular dysfunction. These reports have led to inconsistent definitions of sepsis-induced cardiomyopathy. Just as there is heterogeneity among patients with sepsis, there is heterogeneity in the cardiac response; thus resuscitating these patients with a single approach is likely suboptimal. Many factors affect the heart in sepsis including inflammatory mediators, catecholamine responsiveness, and pathogen related toxins. This review will discuss different functional effects characterized by echocardiographic changes in sepsis and their prognostic and management implications.

Septic cardiomyopathy: Diagnosis and management

There is an extensive body of literature focused on sepsis-induced myocardial dysfunction, but results are conflicting and no objective definition of septic cardiomyopathy (SCM) has been established. SCM may be defined as a sepsis-associated acute syndrome of non-ischemic cardiac dysfunction with systolic and/or diastolic left ventricular (LV) dysfunction and/or right ventricular dysfunction. Physicians should consider this diagnosis in patients with sepsis-associated organ dysfunction, and particularly in cases of septic shock that require vasopressors. Echocardiography is currently the gold standard for diagnosis of SCM. Left ventricular ejection fraction is the most common parameter used to describe LV function in the literature, but its dependence on loading conditions, particularly afterload, limits its use as a measure of intrinsic myocardial contractility. Therefore, repeated echocardiography evaluation is mandatory. Evaluation of global longitudinal strain (GLS) may be more sensitive and specific for SCM than LV ejection fraction (LVEF). Standard management includes etiological treatment, adapted fluid resuscitation, use of vasopressors, and monitoring. Use of inotropes remains uncertain, and heart rate control could be an option in some patients.

Consensus Defined Diastolic Dysfunction and Cardiac Postoperative Morbidity Score: A Prospective Observational Study

Diastolic dysfunction is associated with major adverse outcomes following cardiac surgery. We hypothesized that multisystem endpoints of morbidity would be higher in patients with diastolic dysfunction. A total of 142 patients undergoing cardiac surgical procedures with cardiopulmonary bypass were included in the study. Intraoperative assessments of diastolic function according to the 2016 American Society of Echocardiography and European Association of Cardiovascular Imaging guidelines using transesophageal echocardiography were performed. Cardiac Postoperative Morbidity Score (CPOMS) on days 3, 5, 8, and 15; length of stay in ICU and hospital; duration of intubation; incidence of new atrial fibrillation; 30-day major adverse cardiac and cerebrovascular events were recorded. Diastolic function was determinable in 96.7% of the dataset pre and poststernotomy assessment (n = 240). Diastolic dysfunction was present in 70.9% (n = 88) of measurements before sternotomy and 75% (n = 93) after sternal closure. Diastolic dysfunction at either stage was associated with greater CPOMS on D5 (p = 0.009) and D8 (p = 0.009), with CPOMS scores 1.24 (p = 0.01) higher than in patients with normal function. Diastolic dysfunction was also associated with longer durations of intubation (p = 0.001), ICU length of stay (p = 0.019), and new postoperative atrial fibrillation (p = 0.016, OR (95% CI) = 4.50 (1.22–25.17)). We were able to apply the updated ASE/EACVI guidelines and grade diastolic dysfunction in the majority of patients. Any grade of diastolic dysfunction was associated with greater all-cause morbidity, compared with patients with normal diastolic function.

Echocardiographic Assessment of Left Ventricular Systolic and Diastolic Functions in Dogs with Severe Sepsis and Septic Shock; Longitudinal Study

Simple Summary

Sepsis is associated with cardiovascular changes. The aim of the study was to determine sepsis-induced myocardial dysfunction in dogs with severe sepsis and septic shock using transthoracic echocardiography. Clinical, laboratory and cardiologic examinations for the septic dogs were performed at admission, 6 and 24 h, and on the day of discharge from the hospital. Left ventricular (LV) systolic dysfunction, LV diastolic dysfunction, and both types of the dysfunction were present in 13%, 70%, and 9% of dogs with sepsis, respectively. Dogs with LV diastolic dysfunction had a worse outcome and short-term mortality. Transthoracic echocardiography can be used for monitoring cardiovascular dysfunction in dogs with sepsis.

Abstract

The purpose of this study was to monitor left ventricular systolic dysfunction (LVSD) and diastolic dysfunction (LVDD) using transthoracic echocardiography (TTE) in dogs with severe sepsis and septic shock (SS/SS). A prospective longitudinal study using 23 dogs with SS/SS (experimental group) and 20 healthy dogs (control group) were carried out. All the clinical, laboratory and cardiologic examinations for the experimental dogs were performed at admission, 6 and 24 h after the start of treatment and on the day of discharge. LVSD was described as LV ejection fraction (LVEF) < 50%. LVDD was determined when the septal mitral annulus early diastolic velocity (LVEm) was <8 cm/s. LVSD and LVDD were present in 3 and 16 dogs with SS/SS, respectively, with both types of dysfunction present in 2 of the dogs. Although all the dogs with LVSD survived, 8 dogs with LVDD did not. The survival period was significantly shorter in dogs with an LVEm < 8 cm/s (1.3 ± 1.4 days). In conclusion, LVDD, rather than LVSD, was a common cardiovascular abnormality in the septic dogs, and this may be a negative prognostic factor. TTE is a useful tool for the identifying and monitoring of myocardial dysfunction in the dogs with SS/SS.

Cardiovascular clusters in septic shock combining clinical and echocardiographic parameters: a post hoc analysis

PURPOSE

Mechanisms of circulatory failure are complex and frequently intricate in septic shock. Better characterization could help to optimize hemodynamic support.

METHODS

Two published prospective databases from 12 different ICUs including echocardiographic monitoring performed by a transesophageal route at the initial phase of septic shock were merged for post hoc analysis. Hierarchical clustering in a principal components approach was used to define cardiovascular phenotypes using clinical and echocardiographic parameters. Missing data were imputed.

FINDINGS

A total of 360 patients (median age 64 [55; 74]) were included in the analysis. Five different clusters were defined: patients well resuscitated (cluster 1, n = 61, 16.9%) without left ventricular (LV) systolic dysfunction, right ventricular (RV) failure or fluid responsiveness, patients with LV systolic dysfunction (cluster 2, n = 64, 17.7%), patients with hyperkinetic profile (cluster 3, n = 84, 23.3%), patients with RV failure (cluster 4, n = 81, 22.5%) and patients with persistent hypovolemia (cluster 5, n = 70, 19.4%). Day 7 mortality was 9.8%, 32.8%, 8.3%, 27.2%, and 23.2%, while ICU mortality was 21.3%, 50.0%, 23.8%, 42.0%, and 38.6% in clusters 1, 2, 3, 4, and 5, respectively (p < 0.001 for both).

CONCLUSION

Our clustering approach on a large population of septic shock patients, based on clinical and echocardiographic parameters, was able to characterize five different cardiovascular phenotypes. How this could help physicians to optimize hemodynamic support should be evaluated in the future.

Évaluation de la fonction diastolique du ventricule gauche en réanimation pédiatrique : quelles indications, quels paramètres mesurer ?

L’incidence des patients avec une insuffisance cardiaque diastolique a augmenté au cours des dernières années. De nombreuses études épidémiologiques, physiopathologiques, cliniques ou pronostiques ont été menées pour comprendre cette nouvelle entité. L’étude et l’analyse de la fonction diastolique (FD) sont devenues des temps essentiels de l’examen échocardiographique. Cet article a pour objectifs : 1) de faire le point sur la physiologie de la FD du ventricule gauche (VG) et sur son évaluation chez l’enfant ; 2) d’envisager des applications cliniques en réanimation pédiatrique pour lesquelles son évaluation est importante. L’évaluation de la FD du VG est complexe, en plein essor et encore peu réalisée en pédiatrie. De plus, la tachycardie chez l’enfant et les particularités pédiatriques encore méconnues rendent difficile l’analyse de certains paramètres. L’ETT est l’examen complémentaire incontournable pour évaluer la FD du VG, mais en cours d’étude chez l’enfant. L’évaluation de la FD du VG devrait faire partie intégrante des paramètres échocardiographiques à prendre en considération pour certaines situations (évaluation de la réponse au remplissage vasculaire et de la sevrabilité à la ventilation mécanique, ajustement des traitements…) afin de mieux comprendre sa mesure et l’utiliser en routine clinique. On retiendra que pour l’évaluation échocardiographique chez l’enfant de réanimation : dans un premier temps évaluer la fonction systolique puis s’efforcer d’évaluer l’évolution de la FD par les pressions de remplissage par des paramètres simples (doppler mitral et tissulaire) ajustés au Z-score (urihttp://www.parameterz.comhttp://www.parameterz.com) tels que les rapports E/e’ et E/A, le volume indexé de l’OG, le tout assorti au contexte clinique et à la cinétique des paramètres biologiques (BNP, NT pro-BNP).

Cardiovascular failure and weaning

Cardiac patients are at high risk of weaning failure due to the abrupt burden to the cardiovascular system resulting from the transition from positive-pressure ventilation to spontaneous breathing. Similarly, numerous patients with borderline cardiac function, left ventricular diastolic dysfunction, chronic obstructive pulmonary disease, especially with associated fluid overload or cumulative positive fluid balance, are at high risk of weaning failure of cardiac origin. The diagnosis of weaning-induced pulmonary oedema (WiPO) relies on the measurement of elevated left ventricular filling pressure, or on the presence of a surrogate reflecting pulmonary or cardiac congestion. Plasma concentration of B-type natriuretic peptide and N-terminal proBNP, biological signs of hemoconcentration (increased circulating protein or hemoglobin levels), or measurement of extravascular pulmonary lung water using transpulmonary thermodilution have been proved valuable surrogates for the identification of weaning failure. Nevertheless, studies have not yet compared these indirect methods to precisely determine their respective diagnostic values for the identification of WiPO, especially in heart failure patients. In addition, none of these approaches directly assess left ventricular filling pressure and the mechanism of WiPO. In contrast, critical care echocardiography is ideally suited to establish the diagnosis of weaning failure of cardiac origin. It allows identifying the high-risk population, monitoring hemodynamically the patient at risk, depicting an abrupt increase of left ventricular filling pressure consistent with WiPO when the patient fails weaning, identifying the underlying mechanism of WiPO, and finally it allows tailoring the therapeutic management of the patient who failed weaning. The impact on patient-centered outcomes of such integrated management strategy based on critical care echocardiography deserves to be prospectively tested in a large population of patients at high risk of weaning failure of cardiac origin.

Echocardiographic Evaluation of Ventricular Function-For the Neonatologist and Pediatric Intensivist

In the neonatal and pediatric intensive care setting, bedside cardiac ultrasound is often used to assess ventricular dimensions and function. Depending upon the underlying disease process, it is necessary to be able to evaluate the systolic and diastolic function of left and or right ventricles. The systolic function of left ventricle is mostly assessed qualitatively on visual inspection "eye-balling" and quantitatively by measuring circumferential fraction shortening or calculating the ejection fraction by Simpson's planimetry. The assessment of left ventricular diastolic function relies essentially on the mitral valve and pulmonary venous Doppler tracings or tissue Doppler evaluation. The right ventricular particular shape and anatomical position does not permit to use the same parameters for measuring systolic function as is used for the LV. Tricuspid annular plane systolic excursion (TAPSE) and S' velocity on tissue Doppler imaging are more often used for quantitative assessment of right ventricle systolic function. Several parameters proposed to assess right ventricle systolic function such as fractional area change, 3D echocardiography, speckle tracking, and strain rate are being researched and normal values for children are being established. Diastolic function of right ventricle is evaluated by tricuspid valve and hepatic venous Doppler tracings or on tissue Doppler evaluation. The normal values for children are pretty similar to adults while normal values for the neonates, especially preterm infants, may differ significantly from adult population. The normal values for most of the parameters used to assess cardiac function in term neonates and children have now been established.

Application of updated guidelines on diastolic dysfunction in patients with severe sepsis and septic shock

Background

Left ventricular diastolic dysfunction is suggested to be associated with higher mortality in severe sepsis and septic shock, yet the methods of diagnosis described in the literature are often inconsistent. The recently published 2016 American Society of Echocardiography and European Association of Cardiovascular Imaging (ASE/EACVI) guidelines offer the opportunity to apply a simple pragmatic diagnostic algorithm for the detection of diastolic dysfunction; however, it has not been tested in this cohort.

Aims

We sought to assess the applicability in septic patients of recently published 2016 ASE/EACVI guidelines on diastolic dysfunction compared with the 2009 ASE guidelines. Our hypothesis was that there would be poor agreement in classifying patients.

Methods

Prospective observational study includes patients identified as having severe sepsis and septic shock. Patients underwent transthoracic echocardiography on day 1 and day 3 of their ICU admission. Patients with normal and abnormal (ejection fraction < 52%) systolic function had their diastolic function stratified according to both the 2009 ASE and 2016 ASE/EACVI guidelines.

Results

On day 1 echocardiography, of the 62 patients analysed, 37 (60%) had diastolic dysfunction according to the 2016 ASE/EACVI guideline with a further 23% having indeterminate diastolic function, compared to the 2009 ASE guidelines where only 13 (21%) had confirmed diastolic dysfunction with 46 (74%) having indeterminate diastolic dysfunction. On day 3, of the 55 patients studied, 22 patients (40%) were defined as having diastolic dysfunction, with 6 (11%) having indeterminate diastolic dysfunction according to the 2016 ASE/EACVI guidelines, compared to the 2009 guidelines where 11 (20%) were confirmed to have diastolic dysfunction and 41 (75%) had indeterminate diastolic function. Systolic dysfunction was identified in 18 of 62 patients (29%) on day 1 and 18 of 55 (33%) on day 3. These patients were classified as having abnormal diastolic function in 94 and 89% with the 2016 guidelines on day 1 and day 3, respectively, compared with 50 and 28% using the 2009 guidelines. The 2016 guidelines had less patients with indeterminate diastolic function on days 1 and 3 (11 and 6%) compared to the 2009 guidelines (50 and 72%). Normal systolic function was identified in 44 patients on day 1 and 37 on day 3. In this group, abnormal diastolic function was present in 45 and 54% on days 1 and 3 according to the 2016 ASE/EACVI guidelines, compared with 9 and 16% using the 2009 guidelines, respectively. In those with normal systolic function, the 2016 guidelines had less indeterminate patients with 30 and 16% on days 1 and 3, respectively, compared to 84 and 76% in the 2009 guidelines.

Conclusion

The 2016 ASE/EACVI diastolic function guidelines identify a significantly higher incidence of dysfunction in patients with severe sepsis and septic shock compared to the previous 2009 guidelines. Although the new guidelines seem to be an improvement, issues remain with the application of guidelines using traditional measures of diastolic dysfunction in this cohort.

Electronic supplementary material

The online version of this article (10.1186/s13613-017-0342-x) contains supplementary material, which is available to authorized users.

Detecting impaired myocardial relaxation in sepsis with a novel tissue Doppler parameter (septal e'/s')

Background

Left ventricular diastolic dysfunction is associated with mortality outcomes in severe sepsis and septic shock. There are ongoing issues with diagnosing diastolic dysfunction in this cohort, partly owing to the poor applicability of traditional parameters in the hyperdynamic circulation. In this feasibility study, we sought to assess the utility of a novel parameter (septal e′/s′) to identify diastolic dysfunction in patients with severe sepsis and septic shock who had normal systolic function against the 2016 American Society Echocardiography and European Association of Cardiovascular Imaging (ASE/EACI) guidelines on diastolic dysfunction.

Methods

In this prospective observational pilot study, patients identified as having severe sepsis and septic shock underwent transthoracic echocardiography on day 1 and day 3 of their intensive care unit admission. In patients with normal systolic function, septal e′/s′ was calculated using the peak modal velocity of the s′ compared with the e′ from the septal annulus tissue Doppler imaging and compared with their diastolic grade according to the 2016 ASE/EACI guidelines on diastolic dysfunction.

Results

On day 1 of admission, 44 of 62 patients with severe sepsis and septic shock had normal systolic function. There was a strong association of those with diastolic dysfunction having a reduced septal e′/s′ compared with patients with normal diastolic function (AUC 0.91). A similar relationship was seen with patients who had indeterminate diastolic dysfunction. On day 3, 37 patients had normal systolic function. Again, there was a strong association of those with diastolic dysfunction and a reduced septal e′/s′ (AUC 0.95).

Conclusions

A reduction in septal e′/s′ may indicate diastolic dysfunction in patients with severe sepsis and septic shock who have normal systolic function. As opposed to limited traditional measures of diastolic dysfunction, it is applicable in those with hyperdynamic systolic function.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1727-9) contains supplementary material, which is available to authorized users.

Evaluation of Myocardial Injury using Standard Diagnostic Tools and Tissue Doppler Imaging in Blunt Trauma Chest

INTRODUCTION

Myocardial contusion is an entity in chest trauma which is difficult to diagnose. Current practice relies more on cardiac-specific biochemical markers and standard echocardiography, but no gold standard test exists. The application of Tissue Doppler imaging is yet unexplored.

AIM

The present study was designed to evaluate cardiac injury in patients with blunt trauma chest using conventional trans-thoracic echocardiography parameters and Tissue Doppler imaging.

MATERIALS AND METHODS

After ethical approval was taken from the Hospital and University and a written informed consent from all patients/attendants, this prospective study was conducted on a total of 30 patients in range of 15-60 years of age with blunt trauma chest. Patients with positive Trop-T and raised CPK (> 308 IU/L), raised CK-MB (> 24 IU/L) levels were suspected to have myocardial injury and were enrolled in the study. All patients fulfilling the inclusion criteria then underwent 2D-Echo and Tissue Doppler Imaging. Results of the observations were analysed using chi-square test.

RESULTS

Out of the total of 30 patients, 63.3% showed ECG changes suggestive of cardiac injury. A 76.7% patients suffered systolic dysfunction and 36.6% patients suffered diastolic dysfunction irrespective of ECG changes. On comparison of early filling velocity wave i.e., E wave (measured by transthoracic echocardiography) and tricuspid annular velocity Em wave (measured by tissue Doppler echocardiography) at tricuspid valve, we found statistically significant difference among two techniques. (p = 0.04).

CONCLUSION

Echocardiography is very sensitive parameter for evaluation of myocardial contusion. Tissue Doppler imaging provides additional and reliable information.

The evolution of diastolic function during liver transplantation

INTRODUCTION

The peroperative management of liver transplantation is still associated with many cardiocirculatory complications in which diastolic dysfunction may play a contributive role. Transoesophageal echocardiography is a monitoring device commonly used in liver transplantation allowing diastolic function assessment.

METHODS

We prospectively analysed the peroperative transoesophageal echocardiography recordings of 40 patients undergoing liver transplantation in order to describe changes in diastolic function at different steps of the surgery. The diastolic function marker we used was the lateral mitral annulus motion (E' wave velocity) obtained by tissue-Doppler imaging. In addition, we also studied the left ventricular filling pressure indices and systolic function.

RESULTS

As a whole, there was no global change in E' wave velocity throughout the surgery. However, 11 patients (27.5%) presented a decrease in E' wave velocity up to 15% that identified an occurrence of diastolic function alteration. In this group, other peroperative data were not different from other patients (amount of bleeding, fluid administration or vasopressive support). Conversely, this group experienced lower preoperative E' wave velocity values (9cm·s^-1 versus 12cm·s^-1, P=0.05) and an increased incidence of postoperative cardiorespiratory complications (OR=6 [1-56], P=0.02). Considering all patients, 18 patients had an E' wave velocity under 10cm·s^-1 at unclamping, characterizing a diastolic dysfunction according to the usual criteria. This dysfunction was not associated with cardiorespiratory complications.

CONCLUSION

This work investigated peroperative systematic echocardiographic evaluation of diastolic function during liver transplantation. Diastolic dysfunction occurs frequently during liver transplantation and could lead to postoperative cardiorespiratory complications.

Critical care ultrasonography in acute respiratory failure

Acute respiratory failure (ARF) is a leading indication for performing critical care ultrasonography (CCUS) which, in these patients, combines critical care echocardiography (CCE) and chest ultrasonography. CCE is ideally suited to guide the diagnostic work-up in patients presenting with ARF since it allows the assessment of left ventricular filling pressure and pulmonary artery pressure, and the identification of a potential underlying cardiopathy. In addition, CCE precisely depicts the consequences of pulmonary vascular lesions on right ventricular function and helps in adjusting the ventilator settings in patients sustaining moderate-to-severe acute respiratory distress syndrome. Similarly, CCE helps in identifying patients at high risk of ventilator weaning failure, depicts the mechanisms of weaning pulmonary edema in those patients who fail a spontaneous breathing trial, and guides tailored therapeutic strategy. In all these clinical settings, CCE provides unparalleled information on both the efficacy and tolerance of therapeutic changes. Chest ultrasonography provides further insights into pleural and lung abnormalities associated with ARF, irrespective of its origin. It also allows the assessment of the effects of treatment on lung aeration or pleural effusions. The major limitation of lung ultrasonography is that it is currently based on a qualitative approach in the absence of standardized quantification parameters. CCE combined with chest ultrasonography rapidly provides highly relevant information in patients sustaining ARF. A pragmatic strategy based on the serial use of CCUS for the management of patients presenting with ARF of various origins is detailed in the present manuscript.

Application of a simplified definition of diastolic function in severe sepsis and septic shock

BACKGROUND

Left ventricular diastolic dysfunction is common in patients with severe sepsis or septic shock, but the best approach to categorization is unknown. We assessed the association of common measures of diastolic function with clinical outcomes and tested the utility of a simplified definition of diastolic dysfunction against the American Society of Echocardiography (ASE) 2009 definition.

METHODS

In this prospective observational study, patients with severe sepsis or septic shock underwent transthoracic echocardiography within 24 h of onset of sepsis (median 4.3 h). We measured echocardiographic parameters of diastolic function and used random forest analysis to assess their association with clinical outcomes (28-day mortality and ICU-free days to day 28) and thereby suggest a simplified definition. We then compared patients categorized by the ASE 2009 definition and our simplified definition.

RESULTS

We studied 167 patients. The ASE 2009 definition categorized only 35 % of patients. Random forest analysis demonstrated that the left atrial volume index and deceleration time, central to the ASE 2009 definition, were not associated with clinical outcomes. Our simplified definition used only e' and E/e', omitting the other measurements. The simplified definition categorized 87 % of patients. Patients categorized by either ASE 2009 or our novel definition had similar clinical outcomes. In both definitions, worsened diastolic function was associated with increased prevalence of ischemic heart disease, diabetes, and hypertension.

CONCLUSIONS

A novel, simplified definition of diastolic dysfunction categorized more patients with sepsis than ASE 2009 definition. Patients categorized according to the simplified definition did not differ from patients categorized according to the ASE 2009 definition in respect to clinical outcome or comorbidities.

Prognostic impact of left ventricular diastolic function in patients with septic shock

Background

Left ventricular (LV) diastolic dysfunction is highly prevalent in the general population and associated with a significant morbidity and mortality. Its prognostic role in patients sustaining septic shock in the intensive care unit (ICU) remains controversial. Accordingly, we investigated whether LV diastolic function was independently associated with ICU mortality in a cohort of septic shock patients assessed using critical care echocardiography.

Methods

Over a 5-year period, patients hospitalized in a Medical–Surgical ICU who underwent an echocardiographic assessment with digitally stored images during the initial management of a septic shock were included in this retrospective single-center study. Off-line echocardiographic measurements were independently performed by an expert in critical care echocardiography who was unaware of patients’ outcome. LV diastolic dysfunction was defined by the presence of a lateral E′ maximal velocity <10 cm/s. A multivariate analysis was performed to determine independent risk factors associated with ICU mortality.

Results

Among the 540 patients hospitalized in the ICU with septic shock during the study period, 223 were studied (140 men [63 %]; age 64 ± 13 years; SAPS II 55 ± 18; SOFA 10 ± 3; Charlson 3.5 ± 2.5) and 204 of them (91 %) were mechanically ventilated. ICU mortality was 35 %. LV diastolic dysfunction was observed in 31 % of patients. The proportion of LV diastolic dysfunction tended to be higher in non-survivors than in their counterparts (28/78 [36 %] vs. 41/145 [28 %]: p = 0.15). Inappropriate initial antibiotic therapy (OR 4.17 [CI 95 % 1.33–12.5]: p = 0.03), maximal dose of vasopressors (OR 1.38 [CI 95 % 1.16–1.63]: p = 0.01), SOFA score (OR 1.16 [CI 95 % 1.02–1.32]: p = 0.02) and lateral E′ maximal velocity (OR 1.12 [CI 95 % 1.01–1.24]: p = 0.02) were independently associated with ICU mortality. After adjusting for the SAPS II score, inappropriate initial antibiotic therapy and maximal dose of vasopressors remained independent factors for ICU mortality, whereas a trend was only observed for lateral E′ maximal velocity (OR 1.11 [CI 95 % 0.99–1.23]: p = 0.07).

Conclusion

The present study suggests that LV diastolic function might be associated with ICU mortality in patients with septic shock. A multicenter prospective study assessing a large cohort of patients using serial echocardiographic examinations remains required to confirm the prognostic value of LV diastolic dysfunction in septic shock.

Evaluation of pulmonary artery pressure and resistance by pulsed Doppler echocardiography in patients with end-stage renal disease on dialysis therapy

BACKGROUND

Pulmonary hypertension (PH) is one of the most important comorbidities in patients undergoing hemodialysis (HD). The goal of the present work is to determine the possible etiologic factors for its occurrence.

METHODS

The prevalence of PH was estimated by Doppler echocardiography in a cohort of 100 patients aged 49.3 ± 13.9 years on regular HD. Mean pulmonary artery pressure was estimated from pulmonary acceleration time by Mahan's regression equation. Pulmonary vascular resistance and pulmonary capillary wedge pressure were calculated. We focused on the effect of HD on left and right ventricle diastolic and systolic function. Right ventricle systolic function was assessed by tricuspid annular systolic excursion and pulsed Doppler myocardial performance index. Since impaired endothelial function was postulated as an underlying cause of PH, we studied the effects of HD on brachial artery endothelial function.

RESULTS

The current study found that pulmonary hypertension was prevalent in 70% of patients on dialysis. Left atrium diameter, left ventricle mass indexed to body surface area, and mitral E/E' were increased in the dialysis group (4.4 ± 0.2 cm, 126.5 ± 24.6 g/m(2), and 16.9 ± 4.4, respectively, p < 0.001 for all). Pulmonary artery systolic pressure was positively correlated to duration of dialysis and negatively correlated to glomerular filtration rate (p < 0.001 and r = -0.991). Pulmonary vascular resistance was significantly increased in dialysis patients (1.9 ± 0.2 Wood units vs. 1.2 Wood units in controls, p < 0.001). Endothelial dysfunction, defined as brachial artery flow mediated dilatation <6%, was found in 46% of dialysis group.

CONCLUSION

Increased pulmonary artery systolic pressure in the HD population could be attributed to left atrium dilatation and left ventricle diastolic dysfunction. Pulmonary vascular resistance was significantly increased in dialysis group. This might be explained by impaired endothelial nitric oxide synthesis that not only caused systemic vasoconstriction but also affected the pulmonary vasculature.

Hemodynamic assessment of ventilated ICU patients with cardiorespiratory failure using a miniaturized multiplane transesophageal echocardiography probe

PURPOSE

To assess the feasibility, image quality, diagnostic accuracy, therapeutic impact and tolerance of diagnostic and hemodynamic assessment using a novel miniaturized multiplane transesophageal echocardiography (TEE) probe in ventilated ICU patients with cardiopulmonary compromise.

STUDY DESIGN

Prospective, descriptive, single-center study.

METHODS

Fifty-seven ventilated patients with acute circulatory or respiratory failure were assessed, using a miniaturized multiplane TEE probe and a standard TEE probe used as reference, randomly by two independent experienced operators. Measurements of hemodynamic parameters were independently performed off-line by a third expert. Diagnostic groups of acute circulatory failure (n = 5) and of acute respiratory failure (n = 3) were distinguished. Hemodynamic monitoring was performed in 9 patients using the miniaturized TEE probe. TEE tolerance and therapeutic impact were reported.

RESULTS

The miniaturized TEE probe was easier to insert than the standard TEE probe. Despite lower imaging quality of the miniaturized TEE probe, the two probes had excellent diagnostic agreement in patients with acute circulatory failure (Kappa: 0.95; 95% CI: 0.85-1) and with acute respiratory failure (Kappa: 1; 95% CI: 1.0-1.0). Accordingly, therapeutic strategies derived from both TEE examinations were concordant (Kappa: 0.82; 95% CI: 0.66-0.97). The concordance between quantitative hemodynamic parameters obtained with both TEE probes was also excellent. No relevant complication secondary to TEE probes insertion occurred.

CONCLUSIONS

Hemodynamic assessment of ventilated ICU patients with cardiopulmonary compromise using a miniaturized multiplane TEE probe appears feasible, well-tolerated, and relevant in terms of diagnostic information and potential therapeutic impact. Further larger-scale studies are needed to confirm these preliminary results.

Tissue Doppler indices of diastolic function in critically ill patients and association with mortality - a systematic review

PURPOSE

Systolic impairment is well reported in critically ill patients but diastolic function has been relatively understudied. The objective of this review was to assess tissue Doppler indices of diastolic function in critically ill patients along with any association with mortality.

METHODS

A systematic review of articles in English using Medline, EMBASE, CINAHL and the Cochrane database of systematic reviews. Search terms included diastolic function, diastolic dysfunction, diastolic abnormal*, diastolic heart failure, diastolic filling, ventricular relaxation, pulmonary artery occlusion pressure, left ventricular filling pressure, cardiac dysfunction, intensive care, critical care, critically ill, critical illness, sepsis and septic shock. Only studies of critically ill adult patients (excluding post-cardiac surgical patients) whose diastolic function was assessed using tissue Doppler imaging were included. Study quality was assessed using a modified version of the Newcastle-Ottawa Scale (NOS).

RESULTS

Nineteen studies were included, with a total of 1365 patients. All trials were observational. There was a large heterogeneity in patient populations and the methodology of tissue Doppler assessment of diastology resulting in a descriptive analysis. Patient groups included severe sepsis or septic shock (5 studies), septic shock (5 studies), systemic inflammatory response syndrome and shock (1 study), septic shock and acute lung injury (1 study), cancer and septic shock (2 studies), general ICU patients (1 study), combined medical and surgical ICU (2 studies) and sub-arachnoid haemorrhage patients (2 studies). Seventeen studies scored 5/6 on the NOS with the remaining two scoring 4/6. Fourteen studies reported on numbers of patients diagnosed with diastolic dysfunction (500/999, mean 50%, range 20-92%). Three studies found that diastolic dysfunction was an independent predictor of mortality.

CONCLUSIONS

Current data shows a large range in the incidence of diastolic dysfunction in this patient population and a variable link with mortality. Future research should focus on the definition of normal values for diastolic function in critically ill patients along with the effects of ICU therapies and consensus criteria for its assessment in this patient population.

Acute respiratory distress syndrome (ARDS)-associated acute cor pulmonale and patent foramen ovale: a multicenter noninvasive hemodynamic study

Introduction

Acute cor pulmonale (ACP) and patent foramen ovale (PFO) remain common in patients under protective ventilation for acute respiratory distress syndrome (ARDS). We sought to describe the hemodynamic profile associated with either ACP or PFO, or both, during the early course of moderate-to-severe ARDS using echocardiography.

Methods

In this 32-month prospective multicenter study, 195 patients with moderate-to-severe ARDS were assessed using echocardiography during the first 48 h of admission (age: 56 (SD: 15) years; Simplified Acute Physiology Score: 46 (17); PaO₂/FiO₂: 115 (39); V_T: 6.5 (1.7) mL/kg; PEEP: 11 (3) cmH₂O; driving pressure: 15 (5) cmH₂O). ACP was defined by the association of right ventricular (RV) dilatation and systolic paradoxical ventricular septal motion. PFO was detected during a contrast study using agitated saline in the transesophageal bicaval view.

Results

ACP was present in 36 patients, PFO in 21 patients, both PFO and ACP in 8 patients and the 130 remaining patients had neither PFO nor ACP. Patients with ACP exhibited a restricted left ventricle (LV) secondary to RV dilatation and had concomitant RV dysfunction, irrespective of associated PFO, but preserved LV systolic function. Despite elevated systolic pulmonary artery pressure (sPAP), patients with isolated PFO had a normal RV systolic function. sPAP and PaCO₂ levels were significantly correlated.

Conclusions

In patients under protective mechanical ventilation with moderate-to-severe ARDS, ACP was associated with LV restriction and RV failure, whether PFO was present or not. Despite elevated sPAP, PFO shunting was associated with preserved RV systolic function.

Preoperative fasting does not affect haemodynamic status: a prospective, non-inferiority, echocardiography study

BACKGROUND

The link between preoperative fasting and hypovolaemia remains unclear. We tested the hypothesis that preoperative fasting does not significantly increase the proportion of patients with hypovolaemia according to transthoracic echocardiography (TTE) criteria.

METHODS

Patients of ASA status I-III and without bowel preparation were included in a non-inferiority, prospective, single-centre trial. Patients underwent passive leg raising (PLR) test and TTE at admission (Day 0) and after 8 h fasting (Day 1). The primary hypothesis was that an 8 h preoperative fasting does not increase the proportion (margin=5%) of patients with a positive PLR test ('functional approach'). The secondary hypothesis was that echocardiographic filling pressures or stroke volume (margin 10%) are not affected by preoperative fasting ('static approach').

RESULTS

One hundred patients were included and 98 analysed. After an 8 h fasting, the change in the proportion of responders to PLR was -6.1% [95% confidence interval (CI)=-16.0 to 3.8] of responders to PLR test on Day 0 when compared with Day 1. Because 95% CI was strictly inferior to 5%, there was no significant increase in the proportion of PLR responders on Day 1 when compared with Day 0. The 95% CI changes of static variables were always fewer than 10%, meaning that preoperative fasting induced significantly no relevant changes in static variables.

CONCLUSION

Preoperative fasting did not alter TTE dynamic and static preload indices in ASA I-III adult patients. These results suggest that preoperative fasting does not induce significant hypovolaemia. Clinical trial registration NCT 01258361.

Ventricular diastolic abnormalities in the critically ill

PURPOSE OF REVIEW

Left-ventricular diastolic dysfunction is associated with various conditions frequently encountered in ICU patients. Due to prolonged relaxation and increased left-ventricular stiffness, patients with diastolic dysfunction are at high risk of developing abrupt pulmonary venous congestion. The present review describes the clinical spectrum of left-ventricular diastolic abnormalities in ICU patients.

RECENT FINDINGS

Left-ventricular diastolic dysfunction is associated with a preserved ejection fraction in half of the patients presenting with acute pulmonary edema. These patients may have dramatic presentation, such as flash pulmonary edema during a hypertensive crisis. Left-ventricular diastolic dysfunction is frequently involved in patients who fail extubation and may trigger weaning pulmonary edema. Sepsis and myocardial ischemia may also be associated with left-ventricular diastolic dysfunction. The diagnosis of left-ventricular diastolic dysfunction practically relies on two-dimensional and Doppler echocardiography. Further large-scale clinical studies are needed to better characterize the prevalence, the clinical relevance and time-course of left-ventricular diastolic dysfunction in ICU patients.

SUMMARY

Left-ventricular diastolic dysfunction accounts for a growing proportion of cardiogenic pulmonary edema and weaning failure in ICU patients. It may be reversible when induced by sepsis or myocardial ischemia. Its prognostic value in the ICU settings remains to be further investigated.

Ventricular performance after surgery for a congenital heart defect as assessed using advanced echocardiography: from doppler flow to 3D echocardiography and speckle-tracking strain imaging

A varying degree of impairment of ventricular performance is observed over the long-term after surgery for a congenital heart defect (CHD). Impaired ventricular performance has been shown to be of prognostic value for increased risk of cardiovascular events in adult CHD patients. This emphasizes the importance of delineating the timing and cause of this postoperative impairment. Impairment of ventricular performance could develop over time as a consequence of residua, sequelae and complications of the CHD or surgical procedure. Yet, impaired ventricular performance has also been observed immediately after surgery and can persist and/or worsen over time. This postoperative impairment of ventricular performance is the focus of this review. This article provides an overview of echocardiographic techniques currently used to assess ventricular performance. Furthermore, we review current literature describing ventricular performance, as assessed using echocardiography, after correction of a CHD. In general, a decrease in ventricular performance is observed directly after surgery for CHD’s. Subsequent follow-up of ventricular performance is characterized by a varying degree of postoperative recovery. A consistent observation is the persistent impairment of right-ventricular performance after repair in several different subgroups of CHD patients ranging from ventricular septal defect repair to surgery for Tetralogy of Fallot.

Tissue Doppler imaging detects impaired biventricular performance shortly after congenital heart defect surgery

Cardiac surgery with cardiopulmonary bypass is associated with the development of a systemic inflammatory response, which can lead to myocardial damage. However, knowledge concerning the time course of ventricular performance deterioration and restoration after correction of a congenital heart defect (CHD) in pediatric patients is sparse. Therefore, the authors perioperatively quantified left ventricular (LV) and right ventricular (RV) performance using echocardiography. Their study included 141 patients (ages 0-18 years) undergoing CHD correction and 40 control subjects. The study assessed LV systolic performance (fractional shortening) and diastolic performance (mitral Doppler flow) in combination with RV systolic performance [tricuspid annular plane systolic excursion (TAPSE)] and diastolic performance (tricuspid Doppler flow). Additionally, systolic (S') and diastolic (E', A', E/E') tissue Doppler imaging (TDI) measurements were obtained at the LV lateral wall, the interventricular septum, and the RV free wall. Echocardiographic studies were performed preoperatively, 1 day postoperatively, and at hospital discharge after 9 ± 5 days. Although all LV echocardiographic measurements showed a deterioration 1 day after surgery, only LV TDI measurements were impaired in patients at discharge versus control subjects (S': 5.7 ± 2.0 vs 7.1 ± 2.7 cm/s; E': 9.8 ± 3.9 vs 13.7 ± 5.1 cm/s; E/E': 12.2 ± 6.4 vs 8.8 ± 4.3; p < 0.05). In the RV, TAPSE and RV TDI velocities also were impaired in patients at discharge versus control subjects (TAPSE: 9 ± 3 vs 17 ± 5 mm; S': 5.2 ± 1.7 vs 11.4 ± 3.4 cm/s; E': 7.3 ± 2.5 vs 16.3 ± 5.2 cm/s; E/E': 12.5 ± 6.8 vs 4.8 ± 1.9; p < 0.05). Furthermore, longer aortic cross-clamp times were associated with more impaired postoperative LV and RV performance (p < 0.05). In conclusion, both systolic and diastolic biventricular performances were impaired shortly after CHD correction. This impairment was detected only by TDI parameters and TAPSE. Furthermore, a longer-lasting negative influence of cardiopulmonary bypass on myocardial performance was suggested.

Sepsis-induced cardiomyopathy

Myocardial dysfunction is one of the main predictors of poor outcome in septic patients, with mortality rates next to 70%. During the sepsis-induced myocardial dysfunction, both ventricles can dilate and diminish its ejection fraction, having less response to fluid resuscitation and catecholamines, but typically is assumed to be reversible within 7-10 days. In the last 30 years, It´s being subject of substantial research; however no explanation of its etiopathogenesis or effective treatment have been proved yet. The aim of this manuscript is to review on the most relevant aspects of the sepsis-induced myocardial dysfunction, discuss its clinical presentation, pathophysiology, etiopathogenesis, diagnostic tools and therapeutic strategies proposed in recent years.

Echocardiographic Measures of Diastolic Function Are Preload Dependent during Triggered Positive Pressure Ventilation: A Controlled Crossover Study in Healthy Subjects

Background. The use of echocardiography in intensive care settings impacts decision making. A prerequisite for the use of echocardiography is relative resistance to changes in volume status and levels of positive pressure ventilation (PPV). Studies on indices of diastolic function report conflicting results with regard to dependence on volume status. Evidence is scarce on PPV. Methods. Ten healthy subjects were exposed to 6 levels of positive end-expiratory pressure (PEEP) and pressure support (PS) following a baseline reading. All ventilator settings were performed at three positions: horizontal, reverse-Trendelenburg, and Trendelenburg. Echocardiography was performed throughout. Results. During spontaneous breathing, early diastolic transmitral velocity (E) changed with positioning (P < 0.001), whereas early diastolic velocity of the mitral annulus (e') was independent (P = 0.263). With PPV, E and e' proved preload dependent (P   values < 0.001). Increases in PEEP, PS, or a combination influenced E and e' in reverse-Trendelenburg- and horizontal positions, but not in the Trendelenburg position. Discussion. The change towards preload dependency of e' with PPV suggests that PPV increases myocardial preload sensitivity. The susceptibility of E and e' to preload changes during PPV discourages their use in settings of volume shifts or during changes in ventilator settings. Conclusion. Positioning and PPV affect E and e'.

Influence of acute preload changes on mitral annulus velocity measured by tissue Doppler echocardiography in critically ill patients

AIM

The assessment of diastolic function remains difficult in critical care patients because of unstable preload conditions. Described as fairly insensitive to preload changes, tissue Doppler velocity measurement at the lateral mitral annulus (e' (lat) ) may help evaluate diastolic function. Our aim was to prospectively evaluate e' (lat) changes in relation to fluid expansion in critically ill patients.

METHODS

This prospective observational study was conducted in critically ill, mechanically ventilated, patients in sinus rhythm without previously known cardiac disease. Echocardiography was performed before and 1 hour after a fluid challenge (infusion of Gelofusine 500 ml in 30 minutes). Conventional pulsed wave Doppler indices of left ventricular diastolic function and tissue Doppler velocity lateral (e' (lat) ) and septal (e' (sept) ) mitral annulus velocity were measured, whereas hemodynamic data were simultaneously collected.

RESULTS

Twenty patients (age, 55 ± 15 years; Simplified Acute Physiology Score II, 45 ± 10) were enrolled. Systolic function was preserved in all patients. Cardiac index increased (p < 0.05), as did early diastolic mitral velocity (E wave) (p = 0.001), and e' (lat) and e' (sept) (p = 0.02) after fluid challenge.

CONCLUSIONS

This study confirms the preload dependence and limited clinical usefulness of most Doppler variables, such as e' (lat) , to evaluate diastolic function in intensive care unit patients. Indices, such as E/e', may be of interest in these cases.

Preload dependence of gated cardiac SPECT-derived ventricular volumes in hemodialysis patients

BACKGROUND

In hemodialysis (HD) patients, the intravascular volume expansion of the pre-HD state leads to a high preload. We aim to examine its effect on myocardial perfusion gated SPECT (MPGS)-derived left ventricular (LV) volumes.

METHODS

The study comprised 50 end-stage renal disease (ESRD) patients on HD with normal 2-day stress/rest MPGS performed for kidney transplantation risk assessment. Patients (pts) comprised 23 men/27 women, with mean age of 59.4 ± 7.1 years. The time elapsed from the last HD session in hours was calculated on both days, and patients were classified according to whether it was higher (group A: 19 pts), lower (group B: 27 pts), or equal (group C: 4 pts) on the stress vs the rest day. End-diastolic, end-systolic volumes (EDV, ESV), and left ventricular ejection fraction (LVEF) were determined using QGS™ software. Transient ischemic dilation (TID) ratios were derived from the nongated images using QPS™ software.

RESULTS

Volumes were significantly higher at stress in group A, at rest in group B, and similar in group C. TID ratios were significantly higher in group A vs groups B and C.

CONCLUSIONS

MPGS-derived ventricular volumes are preload dependent. The high preload of the pre-HD state may mimic ischemic TID if occurring on the stress day and create confusion if coinciding with the rest day.

Left ventricular strain and peak systolic velocity: responses to controlled changes in load and contractility, explored in a porcine model

BACKGROUND

Tissue velocity echocardiography is increasingly used to evaluate global and regional cardiac function. Previous studies have suggested that the quantitative measurements obtained during ejection are reliable indices of contractility, though their load-sensitivity has been studied in different settings, but still remains a matter of controversy. We sought to characterize the effects of acute load change (both preload and afterload) and change in inotropic state on peak systolic velocity and strain as a measure of LV contractility.

METHODS

Thirteen anesthetized juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and transthoracic echocardiography. Transient inflation of a vena cava balloon catheter produced controlled load alterations. At least eight consecutive beats in the sequence were analyzed with tissue velocity echocardiography during the load alteration and analyzed for change in peak systolic velocities and strain during same contractile status with a controlled load alteration. Two pharmacological inotropic interventions were also included to generate several myocardial contractile conditions in each animal.

RESULTS

Peak systolic velocities reflected the drug-induced changes in contractility in both radial and longitudinal axis. During the acute load change, the peak systolic velocities remain stable when derived from signal in the longitudinal axis and from the radial axis. The peak systolic velocity parameter demonstrated no strong relation to either load or inotropic intervention, that is, it remained unchanged when load was systematically and progressively varied (peak systolic velocity, longitudinal axis, control group beat 1-5.72 ± 1.36 with beat 8-6.49 ± 1.28 cm/sec, 95% confidence interval), with the single exception of the negative inotropic intervention group where peak systolic velocity decreased a small amount during load reduction (beat 1-3.98 ± 0.92 with beat 8-2.72 ± 0.89 cm/sec). Systolic strain, however, showed a clear degree of load-dependence.

CONCLUSIONS

Peak systolic velocity appears to be load-independent as tested by beat-to-beat load reduction, while peak systolic strain appears to be load-dependent in this model. Peak systolic velocity, in a controlled experimental model where successive beats during load alteration are assessed, has a strong relation to contractility. Peak systolic velocity, but not peak strain rate, is largely independent of load, in this model. More study is needed to confirm this finding in the clinical setting.

Diastolic dysfunction and mortality in early severe sepsis and septic shock: a prospective, observational echocardiography study

Background

Patients with severe sepsis or septic shock often exhibit significant cardiovascular dysfunction. We sought to determine whether severity of diastolic dysfunction assessed by transthoracic echocardiography (TTE) predicts 28-day mortality.

Methods

In this prospective, observational study conducted in two intensive care units at a tertiary care hospital, 78 patients (age 53.2 ± 17.1 years; 51% females; mean APACHE II score 23.3 ± 7.4) with severe sepsis or septic shock underwent TTE within 6 h of ICU admission, after 18 to 32 h, and after resolution of shock. Left ventricular (LV) diastolic dysfunction was defined according to modified American Society of Echocardiography 2009 guidelines using E, A, and e’ velocities; E/A and E/e’; and E deceleration time. Systolic dysfunction was defined as an ejection fraction < 45%.

Results

Twenty-seven patients (36.5%) had diastolic dysfunction on initial echocardiogram, while 47 patients (61.8%) had diastolic dysfunction on at least one echocardiogram. Total mortality was 16.5%. The highest mortality (37.5%) was observed among patients with grade I diastolic dysfunction, an effect that persisted after controlling for age and APACHE II score. At time of initial TTE, central venous pressure (CVP) (11+/- 5 mmHg) did not differ among grades I-III, although patients with grade I received less intravenous fluid.

Conclusions

LV diastolic dysfunction is common in septic patients. Grade I diastolic dysfunction, but not grades II and III, was associated with increased mortality. This finding may reflect inadequate fluid resuscitation in early sepsis despite an elevated CVP, suggesting a possible role for TTE in sepsis resuscitation.

Feasibility of right ventricular longitudinal systolic function evaluation with transthoracic echocardiographic indices derived from tricuspid annular motion: a preliminary study in acute respiratory distress syndrome

INTRODUCTION

Assessment of right ventricular (RV) function in patients with acute respiratory distress syndrome (ARDS) remains challenging. Transthoracic echocardiographic (TTE) indices based on longitudinal systolic RV function are now considered as a reliable evaluation of RV function. We investigated feasibility of two methods in ARDS patients.

METHODS

Prospective observational study. TTE was performed after 12-36 hours of mechanical ventilation. Feasibility of tricuspid annular motion (S(t) ), tricuspid annular plane systolic excursion (TAPSE) was compared to usual two-dimensional (2D) study: fractional area change (RV(FAC) ) and ratio of right to left ventricular end-diastolic area (RVEDA/LVEDA).

RESULTS

Fifty patients were investigated, with TTE possible in all but two patients. Feasibility was 62% for RV(FAC), 72% for RVEDA/LVEDA, and 96% for TAPSE and S(t). RV dilatation (RVEDA/LVEDA ≥ 0.60) was found in 16 patients, including 4 patients with acute cor pulmonale. A longitudinal RV dysfunction (TAPSE < 12 mm or S(t) < 11.5 cm/sec) was suspected in 30% of patients. Relation between both longitudinal indices was modest (r(2) = 0.36, P < 0.001). TAPSE (but not S(t) ) was found poorly related to RV(FAC) (r(2) = 0.27, P = 0.03). Both indices were related to LV function (S(t) : r(2) = 0.27, TAPSE: r(2) = 0.17, both P < 0.05).

CONCLUSION

Despite a superior feasibility than 2D study, our results suggest that both indices may not bring identical information to echo study. TAPSE may be more adapted to ICU use than S(t) . Both should be further investigated in terms of analysis of RV function and ventricular interdependence. Their relations with LV function may limit their use as sole markers of RV function in this population.

Can transthoracic echocardiography be used to predict fluid responsiveness in the critically ill patient? A systematic review

Introduction. We systematically evaluated the use of transthoracic echocardiography in the assessment of dynamic markers of preload to predict fluid responsiveness in the critically ill adult patient. Methods. Studies in the critically ill using transthoracic echocardiography (TTE) to predict a response in stroke volume or cardiac output to a fluid load were selected. Selection was limited to English language and adult patients. Studies on patients with an open thorax or abdomen were excluded. Results. The predictive power of diagnostic accuracy of inferior vena cava diameter and transaortic Doppler signal changes with the respiratory cycle or passive leg raising in mechanically ventilated patients was strong throughout the articles reviewed. Limitations of the technique relate to patient tolerance of the procedure, adequacy of acoustic windows, and operator skill. Conclusions. Transthoracic echocardiographic techniques accurately predict fluid responsiveness in critically ill patients. Discriminative power is not affected by the technique selected.

Cardiac function in Vietnamese patients with different dengue severity grades

OBJECTIVE

Dengue continues to cause significant global morbidity and mortality. Severe disease is characterized by cardiovascular compromise from capillary leakage. Cardiac involvement in dengue has also been reported but has not been adequately studied.

SETTING

Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam.

SUBJECTS AND DESIGN

Seventy-nine patients aged 8-6 yrs with different dengue severity grades were studied using echocardiography including tissue Doppler imaging. The patients were split into severity grades: dengue, dengue with warning signs, and severe dengue. Changes in cardiac functional parameters and hemodynamic indices were monitored over the hospital stay.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

Patients with severe dengue had worse cardiac function compared with dengue in the form of left ventricular systolic dysfunction with increased left myocardial performance index (0.58 [0.26-0.80] vs. 0.38 [0.22-0.70], p = .006). Septal myocardial systolic velocities were reduced (6.4 [4.8-10] vs. 8.1 [6-13] cm/s, p = .01) as well as right ventricular systolic (11.4 [7.5-17] vs. 13.5 [10-17] cm/s, p = .016) and diastolic velocities (13 [8-23] vs. 17 [12-25] cm/s, p = .0026). In the severe group, these parameters improved from hospital admission to discharge; septal myocardial systolic velocities to 8.8 (7-11) cm/s (p = .002), right ventricular myocardial systolic velocities to 15.0 (11.8-23) cm/s, (p = .003), and diastolic velocity to 21 (11-25) cm/s (p = .002). Patients with cardiac impairment were more likely to have significant pleural effusions.

CONCLUSIONS

Patients with severe dengue have evidence of systolic and diastolic cardiac impairment with septal and right ventricular wall being predominantly affected.

French survey on current use of ultrasound in the critical care unit: ECHOREA

INTRODUCTION

Over the last ten years, ultrasound became standard procedure in the intensive care unit (ICU).

STUDY DESIGN

A national survey to evaluate the use of this technique in French ICUs.

METHODS

Three hundred and twenty-seven units were contacted from the listing of the Société de réanimation de langue française (SRLF). A survey containing 20 questions addressing the availability, the training for, and the use of ultrasound was sent to the ICUs. Collection of data took place over a period of three months.

RESULTS

We received 132 completed surveys out of the 327 sent out (40%). Seventy-nine percent of the public community and private centers and 94% of the university centers had an available device in the unit. Forty percent of the units carried out five to ten examinations per week. Seventy-two percent had staff trained in echocardiography. Fifty-five percent used association of monitoring techniques for the haemodynamic assessment of patients with shock. Only 73% carried out formalized reports after examination. In more than 80%, the echocardiograph was also used for the evaluation of other organs.

CONCLUSION

Ultrasound, and particularly echocardiography, has taken on a more prominent role in the routine assessment of critically ill patients. The availability of equipment and of training has increased over the last ten years, but the demand for training in this area remains strong. This French survey confirms this technique became the "extension of the hand" of the intensivist in ICU.

Perioperative assessment of diastolic dysfunction

Assessment of diastolic function should be a component of a comprehensive perioperative transesophageal echocardiographic examination. Abnormal diastolic function exists in >50% of patients presenting for cardiac and high-risk noncardiac surgery, and has been shown to be an independent predictor of adverse postoperative outcome. Normalcy of systolic function in 50% of patients with congestive heart failure implicates diastolic dysfunction as the probable etiology. Comprehensive evaluation of diastolic function requires the use of various, load-dependent Doppler techniques This is further complicated by the additional effects of dehydration and anesthetic drugs on myocardial relaxation and compliance as assessed by these Doppler measures. The availability of more sophisticated Doppler techniques, e.g., Doppler tissue imaging and flow propagation velocity, makes it possible to interrogate left ventricular diastolic function with greater precision, analyze specific stages of diastole, and to differentiate abnormalities of relaxation from compliance. Additionally, various Doppler-derived ratios can be used to estimate left ventricular filling pressures. The varying hemodynamic environment of the operating room mandates modification of the diagnostic algorithms used for ambulatory cardiac patients when left ventricular diastolic function is evaluated with transesophageal echocardiography in anesthetized surgical patients.

Echocardiographic hemodynamic monitoring in the critically ill patient

Echocardiography has shown to be an essential diagnostic tool in the critically ill patient's assessment. In this scenario the initial fluid therapy, such as it is recommended in the actual clinical guidelines, not always provides the desired results and maintains a considerable incidence of cardiorrespiratory insufficiency. Echocardiography can council us on these patients' clinical handling, not only the initial fluid therapy but also on the best-suited election of the vasoactive/ inotropic treatment and the early detection of complications. It contributes as well to improving the etiological diagnosis, allowing one to know the heart performance with more precision. The objective of this manuscript is to review the more important parameters that can assist the intensivist in theragnosis of hemodynamically unstable patients.

A pilot study of patients with clinically severe obesity undergoing laparoscopic surgery: evidence for impaired cardiac performance

OBJECTIVE

Given the propensity for heart disease in obese patients, the authors investigated the effects of pneumoperitoneum on cardiac performance.

DESIGN

A pilot observational intraoperative study.

SETTING

A single-center university hospital.

PARTICIPANTS

Patients undergoing laparoscopic gastric bypass surgery.

INTERVENTIONS

Abdominal insufflation.

MEASUREMENTS AND RESULTS

Hemodynamic, respiratory, and echocardiographic data were collected at 4 epochs: (1) baseline after the induction of anesthesia, (2) after abdominal insufflation in supine position, (3) after abdominal insufflation in the reverse Trendelenburg (RT) position, and (4) after desufflation in RT position. At epoch 1, 3 of 13 patients manifested systolic dysfunction (SD), 5 of 13 patients exhibited diastolic dysfunction (DD) according to transmitral flow (TMF) Doppler criteria, and 4 of 8 patients according to Doppler tissue imaging (DTI) criteria. With pneumoperitoneum, the total systemic resistance increased to values of 142% from baseline (p < 0.05). Compared with baseline, stroke volume decreased by 25%, cardiac output by 35%, and fractional area change by 13% (p < 0.05). Mean arterial blood pressure and heart rate remained stable. Additionally, new-onset DD manifested in 1 of 8 patients according to TMF criteria and in 3 of 4 patients according to DTI criteria. Desufflation of the abdomen reverted the diastolic function to baseline in all but 1 patient.

CONCLUSION

The study data revealed that surgical pneumoperitoneum used in patients with clinically severe obesity resulted in the deterioration of cardiac performance including the development of new-onset DD. These patients, despite their relative young age and without a history of heart failure or coronary artery disease, displayed a cardiovascular profile during laparoscopic surgery similar to that seen in patients with significant heart disease.

Echocardiography: a help in the weaning process

Introduction

To evaluate the ability of transthoracic echocardiography (TTE) to detect the effects of spontaneous breathing trial (SBT) on central hemodynamics and to identify indices predictive of cardiac-related weaning failure.

Methods

TTE was performed just before and at the end of a 30-min SBT in 117 patients fulfilling weaning criteria. Maximal velocities of mitral E and A waves, deceleration time of E wave (DTE), maximal velocity of E' wave (tissue Doppler at the lateral mitral annulus), and left ventricular (LV) stroke volume were measured. Values of TTE parameters were compared between baseline (pressure support ventilation) and SBT in all patients and according to LV ejection fraction (EF): >50% (n = 58), 35% to 50% (n = 30), and <35% (n = 29). Baseline TTE indices were also compared between patients who were weaned (n = 94) and those who failed (n = 23).

Results

Weaning failure was of cardiac origin in 20/23 patients (87%). SBT resulted in a significant increase in cardiac output and E/A, and a shortened DTE. At baseline, DTE was significantly shorter in patients with LVEF <35% when compared to other subgroups (median [25^th-75^th percentiles]: 119 ms [90-153]; vs. 187 ms [144-224] vs. 174 ms [152-193]; P < 0.01) and E/E' was greater (7.9 [5.4-9.1] vs. 6.0 [5.3-9.0] vs. 5.2 [4.7-6.0]; P < 0.01). When compared to patients who were successfully weaned, those patients who failed exhibited at baseline a significantly lower LVEF (36% [27-55] vs. 51% [43-55]: P = 0.04) and higher E/E' (7.0 [5.0-9.2] vs. 5.6 [5.2-6.3]: P = 0.04).

Conclusions

TTE detects SBT-induced changes in central hemodynamics. When performed by an experienced operator prior to SBT, TTE helps in identifying patients at high risk of cardiac-related weaning failure when documenting a depressed LVEF, shortened DTE and increased E/E'. Further studies are needed to evaluate the impact of this screening strategy on the weaning process and patient outcome.

Prediction of hospital outcome in septic shock: a prospective comparison of tissue Doppler and cardiac biomarkers

Introduction

Diastolic dysfunction as demonstrated by tissue Doppler imaging (TDI), particularly E/e' (peak early diastolic transmitral/peak early diastolic mitral annular velocity) is common in critical illness. In septic shock, the prognostic value of TDI is undefined. This study sought to evaluate and compare the prognostic significance of TDI and cardiac biomarkers (B-type natriuretic peptide (BNP); N-terminal proBNP (NTproBNP); troponin T (TnT)) in septic shock. The contribution of fluid management and diastolic dysfunction to elevation of BNP was also evaluated.

Methods

Twenty-one consecutive adult patients from a multidisciplinary intensive care unit underwent transthoracic echocardiography and blood collection within 72 hours of developing septic shock.

Results

Mean ± SD APACHE III score was 80.1 ± 23.8. Hospital mortality was 29%. E/e' was significantly higher in hospital non-survivors (15.32 ± 2.74, survivors 9.05 ± 2.75; P = 0.0002). Area under ROC curves were E/e' 0.94, TnT 0.86, BNP 0.78 and NTproBNP 0.67. An E/e' threshold of 14.5 offered 100% sensitivity and 83% specificity. Adjustment for APACHE III, cardiac disease, fluid balance and grade of diastolic function, demonstrated E/e' as an independent predictor of hospital mortality (P = 0.019). Multiple linear regression incorporating APACHE III, gender, cardiac disease, fluid balance, noradrenaline dose, C reactive protein, ejection fraction and diastolic dysfunction yielded APACHE III (P = 0.033), fluid balance (P = 0.001) and diastolic dysfunction (P = 0.009) as independent predictors of BNP concentration.

Conclusions

E/e' is an independent predictor of hospital survival in septic shock. It offers better discrimination between survivors and non-survivors than cardiac biomarkers. Fluid balance and diastolic dysfunction were independent predictors of BNP concentration in septic shock.

Use of ultrasound in the ICU

Echography has developed as an indispensable tool in diagnosis and subsequent therapy in the critically ill. Although pulmonary and abdominal ultrasounds play a major role in their management, this article will discuss the advantages and indications of echocardiography in the intensive care unit (ICU). The assessment of morphological abnormalities, left or right ventricular malfunction, pulmonary arterial hypertension and valvular dysfunctions is a routine indication of echocardiography. Actually, besides contractility, several preload and even afterload indicators can also be assessed. In short, this bedside tool rapidly provides insight in the haemodynamics without invasive pressure estimations.