Right ventricular dysfunction in low output syndrome after cardiac operations: assessment by transesophageal echocardiography

Incidence, factors, and prognostic analyses of challenging cardiopulmonary bypass separation in Chinese cardiac surgical populations

BACKGROUND

Challenging separation from cardiopulmonary bypass (CPB) has been associated with multiple medical adversities, while its incidence, associated factors, and prognosis among cardiac surgery populations are substantially understudied.

METHODS

Adult cardiac surgical patients in two medical centers were retrospectively analyzed. Separation from CPB was stratified as easy, difficult, or complex, based on the use of pharmacologic assistance agents and mechanical supports. The various in-hospital adverse outcomes (e.g., mortality, common complications) were assessed.

RESULTS

The incidence of difficult and complex separation from CPB was 21.9% (1159 cases, 95% CI 20.8% to 23.1%), and 6.1% (320 cases, 95% CI 5.4% to 6.7%), respectively. High age, the presence of pulmonary hypertension or unstable angina, decreased ejection fraction, and emergency surgery were more frequently associated with challenging separation from CPB. Patients who experienced challenging separation from CPB had an elevated risk of adverse outcomes, including in-hospital mortality (complex: odds ratio [OR] 2.85), composite infection events (difficult: OR=1.82; complex: OR=1.88), major adverse cardiac events (difficult: OR=1.40; complex: OR=1.57), pulmonary complications (difficult: OR=1.31; complex: OR=1.20), acute kidney injury (difficult: OR=1.75; complex: OR=2.64), and prolonged postoperative hospital stays.

CONCLUSIONS

We depicted the incidence of challenging separation from CPB among cardiac surgery population. Additionally, results of influential factors and various adverse outcome analyses emphasize the potential of interventions aimed at preventing difficult or complex separation from CPB and reducing associated adverse outcomes.

Perioperative Right Ventricular Dysfunction and Abnormalities of the Tricuspid Valve Apparatus in Patients Undergoing Cardiac Surgery

Right ventricular (RV) dysfunction frequently occurs after cardiac surgery and is linked to adverse postoperative outcomes, including mortality, reintubation, stroke, and prolonged ICU stays. While various criteria using echocardiography and hemodynamic parameters have been proposed, a consensus remains elusive. Distinctive RV anatomical features include its thin wall, which presents a triangular shape in a lateral view and a crescent shape in a cross-sectional view. Principal causes of RV dysfunction after cardiac surgery encompass ischemic reperfusion injury, prolonged ischemic time, choice of cardioplegia and its administration, cardiopulmonary bypass weaning characteristics, and preoperative risk factors. Post-left ventricular assist device (LVAD) implantation RV dysfunction is common but often transient, with a favorable prognosis upon resolution. There is an ongoing debate regarding the benefits of concomitant surgical repair of the RV in the presence of regurgitation. According to the literature, the gold standard techniques for assessing RV function are cardiac magnetic resonance imaging and hemodynamic assessment using thermodilution. Echocardiography is widely favored for perioperative RV function evaluation due to its accessibility, reproducibility, non-invasiveness, and cost-effectiveness. Although other techniques exist for RV function assessment, they are less common in clinical practice. Clinical management strategies focus on early detection and include intravenous drugs (inotropes and vasodilators), inhalation drugs (pulmonary vasodilators), ventilator strategies, volume management, and mechanical support. Bridging research gaps in this field is crucial to improving clinical outcomes associated with RV dysfunction in the near future.

The perioperative use of inhaled prostacyclins in cardiac surgery: a systematic review and meta-analysis

PURPOSE

Perioperative pulmonary hypertension (PH) is an independent risk factor for morbidity and mortality in cardiac surgery. While inhaled prostacyclins (iPGI2s) are an established treatment of chronic PH, data on the efficacy of iPGI2s in perioperative PH are scarce.

METHODS

We searched PubMed, Embase, the Web of Science, CENTRAL, and the grey literature from inception until April 2021. We included randomized controlled trials investigating the use of iPGI2s in adult and pediatric patients undergoing cardiac surgery with an increased risk of perioperative right ventricle failure. We assessed the efficacy and safety of iPGI2s compared with placebo and other inhaled or intravenous vasodilators with random-effect meta-analyses. The primary outcome was mean pulmonary artery pressure (MPAP). Secondary outcomes included other hemodynamic parameters and mortality.

RESULTS

Thirteen studies were included, comprising 734 patients. Inhaled prostacyclins significantly decreased MPAP compared with placebo (standardized effect size, 0.46; 95% confidence interval [CI], 0.11 to 0.87; P = 0.01) and to intravenous vasodilators (1.26; 95% CI, 0.03 to 2.49; P = 0.045). Inhaled prostacyclins significantly improved the cardiac index compared with intravenous vasodilators (1.53; 95% CI, 0.50 to 2.57; P = 0.004). In contrast, mean arterial pressure was significantly lower in patients treated with iPGI2s vs placebo (-0.39; 95% CI, -0.62 to 0.16; P = 0.001), but higher than in patients treated with intravenous vasodilators (0.81; 95% CI, 0.29 to 1.33; P = 0.002). With respect to hemodynamics, iPGI2s had similar effects as other inhaled vasodilators. Mortality was not affected by iPGI2s.

CONCLUSION

The results of this systematic review and meta-analysis show that iPGI2s improved pulmonary hemodynamics with similar efficacy as other inhaled vasodilators, but caused a significant small decrease in arterial pressure when compared with placebo, indicating spill-over into the systemic circulation. These effects did not affect clinical outcomes.

STUDY REGISTRATION DATE

PROSPERO (CRD42021237991); registered 26 May 2021.

Nitric Oxide in Cardiac Surgery: A Review Article

Perioperative organ injury remains a medical, social and economic problem in cardiac surgery. Patients with postoperative organ dysfunction have increases in morbidity, length of stay, long-term mortality, treatment costs and rehabilitation time. Currently, there are no pharmaceutical technologies or non-pharmacological interventions that can mitigate the continuum of multiple organ dysfunction and improve the outcomes of cardiac surgery. It is essential to identify agents that trigger or mediate an organ-protective phenotype during cardiac surgery. The authors highlight nitric oxide (NO) ability to act as an agent for perioperative protection of organs and tissues, especially in the heart-kidney axis. NO has been delivered in clinical practice at an acceptable cost, and the side effects of its use are known, predictable, reversible and relatively rare. This review presents basic data, physiological research and literature on the clinical application of NO in cardiac surgery. Results support the use of NO as a safe and promising approach in perioperative patient management. Further clinical research is required to define the role of NO as an adjunct therapy that can improve outcomes in cardiac surgery. Clinicians also have to identify cohorts of responders for perioperative NO therapy and the optimal modes for this technology.

Guiding Interventions for Secondary Tricuspid Regurgitation: Follow the Intricate Interplay Between Form and Function

Secondary tricuspid regurgitation (TR) has long been considered a benign and well-tolerated valvular lesion that resolves after treatment of the underlying disease. This view has been challenged by data indicating that long-standing TR can be a progressive disorder, contributing to right ventricular failure and end-organ damage, despite adequate treatment of the underlying disease. Surgical correction is curative, but infrequently performed and historically associated with poor outcomes. This may be due to delayed diagnosis, lack of well-defined surgical indications, and, consequently, late intervention in patients in poor clinical condition with failing right ventricles. Because of limited evidence about timing and corresponding outcome of tricuspid valve surgery, current guideline recommendations are rather conservative and show several inconsistencies. Nevertheless, there has been a trend toward a more aggressive approach in the surgical treatment of TR with improved outcomes. Moreover, emerging transcatheter options claim to provide a lower-risk alternative for selected patients. This may facilitate earlier treatment and improve the attitude toward an early treatment strategy of secondary TR, yet is not reflected in the guidelines. Future research is needed for risk stratification to determine inclusion criteria and optimal timing for intervention.

A standardized definition for right ventricular failure in cardiac surgery patients

Right ventricular failure (RVF) is a significant cause of mortality and morbidity after cardiac surgery. Despite its prognostic importance, RVF remains under investigated and without a universally accepted definition in the perioperative setting. We foresee that the provision of a standardized perioperative definition for RVF based on practical and objective criteria will help to improve quality of care through early detection and facilitate the generalization of RVF research to advance this field. This article provides an overview of RVF aetiology, pathophysiology, current diagnostic modalities, as well as a summary of existing RVF definitions. This is followed by our proposal for a standardized definition of perioperative RVF, one that captures RV structural and functional abnormalities through a multimodal approach based on anatomical, echocardiographic, and haemodynamic criteria that are readily available in the perioperative setting (Central Image).

Right Ventricular Outflow Tract Obstruction in Adults: A Systematic Review and Meta-analysis

Background

Right ventricular outflow tract obstruction (RVOTO) is a cause of hemodynamic instability that can occur in several situations, including cardiac surgery, lung transplantation, and thoracic surgery, and in critically ill patients. The timely diagnosis of RVOTO is important because it requires specific considerations, including the adverse effects of positive inotropes, and depending on the etiology, the requirement for urgent surgical intervention.

Methods

The objective of this systematic review and meta-analysis was to determine the prevalence of RVOTO in adult patients, and the distribution of all reported cases by etiology.

Results

Of 233 available reports, there were 229 case reports or series, and 4 retrospective cohort studies, with one study also reporting a prospective cohort. Of 291 reported cases of RVOTO, 61 (21%) were congenital, 56 (19%) were iatrogenic, and 174 (60%) were neither congenital nor iatrogenic (including intracardiac tumour). The mechanism of RVOTO was an intrinsic obstruction in 169 cases (58%), and an extrinsic obstruction in 122 cases (42%). A mechanical obstruction causing RVOTO was present in 262 cases (90%), and 29 cases of dynamic RVOTO (10%) were reported. In the 5 included cohorts, with a total of 1122 patients, the overall prevalence was estimated to be 4.0% (1%-9%).

Conclusions

RVOTO, though rare, remains clinically important, and therefore, multicentre studies are warranted to better understand the prevalence, causes, and consequences of RVOTO.

High Versus Normal Blood Pressure Targets in Relation to Right Ventricular Dysfunction After Cardiac Surgery: A Randomized Controlled Trial

OBJECTIVE

Management of right ventricular (RV) dysfunction is challenging. Current practice predominantly is based on data from experimental and small uncontrolled studies and includes augmentation of blood pressure. However, whether such intervention is effective in the clinical setting of cardiac surgery is unknown.

DESIGN

Randomized controlled trial.

SETTING

Single-center study in a tertiary teaching hospital.

PARTICIPANTS

The study comprised 78 patients equipped with a pulmonary artery catheter (PAC), classified according to PAC-derived RV ejection fraction (RVEF); 44 patients had an RVEF of <20%, and 34 patients had an RVEF between ≥20% and <30%.

INTERVENTIONS

Patients randomly were assigned to either a normal target group (mean arterial pressure 65 mmHg) or a high target group [mean arterial pressure 85 mmHg]). The primary end- point was the change in RVEF over a one-hour study period.

MEASUREMENTS AND MAIN RESULTS

There was no significant between-group difference in change of RVEF <20% (-1% [-3.3 to 1.8] in the normal-target group v 0.5% [-1 to 4] in the high-target group; p = 0.159). There was no significant between-group difference in change in RVEF 20%-to-30% (-1% [-3 to 0] in the normal-target group v 1% [-1 to 3] in the high-target group; p = 0.074). These results were in line with the simultaneous observation that echocardiographic variables of RV and left ventricular function also remained unaltered over time, irrespective of either baseline RVEF or treatment protocol.

CONCLUSION

In a mixed cardiac surgery population with RV dysfunction, norepinephrine-mediated high blood pressure targets did not result in an increase in PAC-derived RVEF compared with normal blood pressure targets.

Inhaled levosimendan versus intravenous levosimendan in patients with pulmonary hypertension undergoing mitral valve replacement

Context:

Inhaled levosimendan may act as selective pulmonary vasodilator and avoid systemic side effects of intravenous levosimendan, which include decrease in systemic vascular resistance (SVR) and systemic hypotension, but with same beneficial effect on pulmonary artery pressure (PAP) and right ventricular (RV) function.

Aim:

The aim of this study was to compare the effect of inhaled levosimendan with intravenous levosimendan in patients with pulmonary hypertension undergoing mitral valve replacement.

Settings and Design:

The present prospective randomized comparative study was conducted in a tertiary care hospital.

Subjects and Methods:

Fifty patients were randomized into two groups (n = 25). Group A: Levosimendan infusion was started immediately after coming-off of cardiopulmonary bypass and continued for 24 h at 0.1 mcg/kg/min. Group B: Total dose of levosimendan which would be given through intravenous route over 24 h was calculated and then divided into four equal parts and administered through inhalational route 6^th hourly over 24 h. Hemodynamic profile (pulse rate, mean arterial pressure, pulmonary artery systolic pressure [PASP], SVR) and RV function were assessed immediately after shifting, at 1, 8, 24, and 36 h after shifting to recovery.

Statistical Analysis Used:

Intragroup analysis was done using paired student t-test, and unpaired student t-test was used for analysis between two groups.

Results:

PASP and RV-fractional area change (RV-FAC) were comparable in the two groups at different time intervals. There was a significant reduction in PASP and significant improvement in RV-FAC with both intravenous and inhalational levosimendan. SVR was significantly decreased with intravenous levosimendan, but no significant decrease in SVR was observed with inhalational levosimendan.

Conclusions:

Inhaled levosimendan is a selective pulmonary vasodilator. It causes decrease in PAP and improvement in RV function, without having a significant effect on SVR.

Lung recruitment improves right ventricular performance after cardiopulmonary bypass: A randomised controlled trial

BACKGROUND

Atelectasis after cardiopulmonary bypass (CPB) can affect right ventricular (RV) performance by increasing its outflow impedance.

OBJECTIVE

The aim of this study was to determine whether a lung recruitment manoeuvre improves RV function by re-aerating the lung after CPB.

DESIGN

Randomised controlled study.

SETTING

Single-institution study, community hospital, Córdoba, Argentina.

PATIENTS

Forty anaesthetised patients with New York Heart Association class I or II, preoperative left ventricular ejection fraction at least 50% and Euroscore 6 or less scheduled for cardiac surgery with CPB.

INTERVENTIONS

Patients were assigned to receive either standard ventilation with 6 cmH2O of positive end-expiratory pressure (PEEP; group C, n = 20) or standard ventilation with a recruitment manoeuvre and 10 cmH2O of PEEP after surgery (group RM, n = 20). RV function, left ventricular cardiac index (CI) and lung aeration were assessed by transoesophageal echocardiography (TOE) before, at the end of surgery and 30 min after surgery.

MAIN OUTCOME MEASURES

RV function parameters and atelectasis assessed by TOE.

RESULTS

Haemodynamic data and atelectasis were similar between groups before surgery. At the end of surgery, CI had decreased from 2.9 ± 1.1 to 2.6 ± 0.9 l min m in group C (P = 0.24) and from 2.8 ± 1.0 to 2.6 ± 0.8 l min m in group RM (P = 0.32). TOE-derived RV function parameters confirmed a mild decrease in RV performance in 95% of patients, without significant differences between groups (multivariate Hotelling t-test P = 0.16). Atelectasis was present in 18 patients in group C and 19 patients in group RM (P = 0.88). After surgery, CI decreased further from 2.6 to 2.4 l min m in group C (P = 0.17) but increased from 2.6 to 3.7 l min m in group RM (P < 0.001). TOE-derived RV function parameters improved only in group RM (Hotelling t-test P < 0.001). Atelectasis was present in 100% of patients in group C but only in 10% of those in group RM (P < 0.001).

CONCLUSION

Atelectasis after CPB impairs RV function but this can be resolved by lung recruitment using 10 cmH2O of PEEP.

TRIAL REGISTRATION

Protocol started on October 2014.

Right Ventricular Function in Left Heart Disease

Right ventricular (RV) function is an independent prognostic factor for short- and long-term outcomes in cardiac surgical patients. Patients with mitral valve (MV) disease are at increased risk of RV dysfunction before and after MV operations. Yet RV function is not part of criteria for decision making or risk stratification in this setting. The role of MV disease in the development of pulmonary hypertension (PHTN) and the ultimate impact of PHTN on RV function have been well described. Nonetheless, there are other mechanisms by which MV disease and MV surgery affect RV performance. Research suggests that PHTN may not be the most important determinant of RV dysfunction. Both RV dysfunction and PHTN have independent prognostic significance. This review explores the unique anatomic and functional features of the RV and the pathophysiologic and prognostic implications of RV dysfunction in patients with MV disease in the perioperative period.

The impact of pericardial approach and myocardial protection onto postoperative right ventricle function reduction

Background

The reduction of RV function after cardiac surgery is a well-known phenomenon. It could persist up-to one year after the operation and often leads to an incomplete recovery at follow-up echocardiographic control. The aim of the present study is to analyze the impact of different modalities of pericardial incision (lateral versus anterior) and of myocardial protection protocols (Buckberg versus Custodiol) onto postoperative RV dynamic by relating two- and three-dimensional echocardiographic parameters in patients undergoing mitral valve repair through minimally invasive or traditional surgery approach.

Methods

We have analyzed 44 consecutive patients with severe degenerative mitral regurgitation who underwent mitral reparation with different surgical approach and cardioplegia type: Group 1 (17 pts): sternotomy with Buckberg cardioplegia protocol; Group 2 (10 pts): sternotomy with Custodiol cardioplegia; Group 3 (17 pts): mini-invasive surgery with Custodiol cardioplegia. Two-dimensional transthoracic echocardiography was performed pre- and 6 months post-surgery to evaluate RV function by tricuspid annular plane systolic excursion (TAPSE).

Results

All patients underwent successful and uneventful. A postoperative TAPSE reduction was found in all groups. However, mini-invasive patients experienced a significant reduced variation versus traditional surgery.

Conclusions

Mini-invasive mitral repair, with lateral incision of pericardium, reduces postoperative TAPSE fall, while cardioplegia protocol fails to have an impact onto longitudinal RV function. In our study, the RV seems to experience a clinically irrelevant geometrical modification too, whose entity appears to be less evident in case of lateral pericardial approach. These results could strengthen the use of minimally invasive approach also to preserve RV function.

Diagnostic workup, etiologies and management of acute right ventricle failure : A state-of-the-art paper

INTRODUCTION

This is a state-of-the-art article of the diagnostic process, etiologies and management of acute right ventricular (RV) failure in critically ill patients. It is based on a large review of previously published articles in the field, as well as the expertise of the authors.

RESULTS

The authors propose the ten key points and directions for future research in the field. RV failure (RVF) is frequent in the ICU, magnified by the frequent need for positive pressure ventilation. While no universal definition of RVF is accepted, we propose that RVF may be defined as a state in which the right ventricle is unable to meet the demands for blood flow without excessive use of the Frank-Starling mechanism (i.e. increase in stroke volume associated with increased preload). Both echocardiography and hemodynamic monitoring play a central role in the evaluation of RVF in the ICU. Management of RVF includes treatment of the causes, respiratory optimization and hemodynamic support. The administration of fluids is potentially deleterious and unlikely to lead to improvement in cardiac output in the majority of cases. Vasopressors are needed in the setting of shock to restore the systemic pressure and avoid RV ischemia; inotropic drug or inodilator therapies may also be needed. In the most severe cases, recent mechanical circulatory support devices are proposed to unload the RV and improve organ perfusion CONCLUSION: RV function evaluation is key in the critically-ill patients for hemodynamic management, as fluid optimization, vasopressor strategy and respiratory support. RV failure may be diagnosed by the association of different devices and parameters, while echocardiography is crucial.

Prostacyclins in Cardiac Surgery: Coming of Age

Prostacyclin (prostaglandin I2 [PGI2]) is an eicosanoid lipid mediator produced by the endothelial cells. It plays pivotal roles in vascular homeostasis by virtue of its potent vasodilatory and antithrombotic effects. Stable pharmacological analogues of PGI2 are used for treatment of pulmonary hypertension and right ventricular failure. PGI2 dose dependently inhibits platelet activation induced by adenosine-5′-diphosphate, arachidonic acid, collagen, and low-dose thrombin. This property has led to its use as an alternative to direct thrombin inhibitors in patients with type II heparin-induced thrombocytopenia (HIT) undergoing cardiac surgery. The aims of this review are the following: (1) to review the pharmacology of PGI2 and its derivatives, (2) to present the evidence for their use in pulmonary hypertension and right heart failure, and (3) to discuss their utility in the management of HIT in cardiac surgery.

Additive and independent prognostic role of abnormal right ventricle and pulmonary hypertension in mitral-tricuspid surgery

OBJECTIVE

To evaluate the additive and independent prognostic value of abnormal right ventricle (aRV) and pulmonary hypertension (PH) in patients undergoing mitral-tricuspid surgery.

METHODS

From January 2009 to December 2012, 541 patients underwent mitro-tricuspid surgery. The entire cohort was divided into 6 subgroups: 63 cases had normal RV and no PH (Group A), 180 normal RV but moderate PH (Group B), 101 normal RV but severe PH (Group C), 15 abnormal RV and no-PH (Group D), 86 abnormal RV and moderate PH (Group E) and 96 abnormal RV and severe PH (Group F).

RESULTS

Forty-two (7.8%) patients died in hospital due to any cause: 1.6% in group A, 3.9% in group B, 8.9% in group C, 13.3% in group D, 9.3% in group E, 15.6% in group E, p = 0.005. Among 78 patients with no-PH, mortality was significantly higher in patients with aRV (1.6%vs 13.3%. p = 0.03). Among 344 patients with normal RV, mortality was significantly higher in patients with severe PH (1.6% vs 3.9% vs 8.9%. p = 0.03). Comparing the presence of both abnormal RV and severe PH with the remaining patients, mortality was significantly higher in the first group (15.6% 6.1%, p = 0.004). Multivariable analysis confirmed either the independent or the additive role of RV and PH.

CONCLUSIONS

In patients undergoing mitral-tricuspid valve surgery, the presence of either RV dysfunction/dilatation or severe pulmonary hypertension, might play an independent prognostic role for mortality. The worst scenario is surely the contemporary presence of both conditions.

Low cardiac output syndrome in the postoperative period of cardiac surgery. Profile, differences in clinical course and prognosis. The ESBAGA study

OBJECTIVES

An analysis is made of the clinical profile, evolution and differences in morbidity and mortality of low cardiac output syndrome (LCOS) in the postoperative period of cardiac surgery, according to the 3 diagnostic subgroups defined by the SEMICYUC Consensus 2012.

DESIGN

A multicenter, prospective cohort study was carried out.

SETTING

ICUs of Spanish hospitals with cardiac surgery.

PATIENTS

A consecutive sample of 2,070 cardiac surgery patients was included, with the analysis of 137 patients with LCOS.

INTERVENTIONS

No intervention was carried out.

RESULTS

The mean patient age was 68.3±9.3 years (65.2% males), with a EuroSCORE II of 9.99±13. NYHA functional class III-IV (52.9%), left ventricular ejection fraction<35% (33.6%), AMI (31.9%), severe PHT (21.7%), critical preoperative condition (18.8%), prior cardiac surgery (18.1%), PTCA/stent placement (16.7%). According to subgroups, 46 patients fulfilled hemodynamic criteria of LCOS (group A), 50 clinical criteria (group B), and the rest (n=41) presented cardiogenic shock (group C). Significant differences were observed over the evolutive course between the subgroups in terms of time subjected to mechanical ventilation (114.4, 135.4 and 180.3min in groups A, B and C, respectively; P<.001), renal replacement requirements (11.4, 14.6 and 36.6%; P=.007), multiorgan failure (16.7, 13 and 47.5%), and mortality (13.6, 12.5 and 35.9%; P=.01). The mean maximum lactate concentration was higher in cardiogenic shock patients (P=.002).

CONCLUSIONS

The clinical evolution of these patients leads to high morbidity and mortality. We found differences between the subgroups in terms of the postoperative clinical course and mortality.

A retrospective comparison of inhaled milrinone and iloprost in post-bypass pulmonary hypertension

During cardiac operations, weaning from cardiopulmonary bypass (CPB) may prove challenging as a result of superimposed acute right ventricular dysfunction in the setting of elevated pulmonary vascular resistance (PVR). The aim of this study was to retrospectively evaluate the effect of inhaled milrinone versus inhaled iloprost in patients with persistent pulmonary hypertension following discontinuation of CPB. Eighteen patients with elevated PVR post-bypass were administered inhaled milrinone at a cumulative dose of 50 μg kg^-1. These patients were retrospectively matched with 18 patients who were administered 20 μg of inhaled iloprost. Both drugs were administered through a disposable aerosol-generating jet nebulizer device and inhaled for a 15-min period. Hemodynamic measurements were performed before and after cessation of the inhalation period. Both inhaled milrinone and inhaled iloprost induced significant reductions in mean pulmonary artery pressure and PVR and significant increases in cardiac index in patients with post-CPB pulmonary hypertension. The favorable effect of both agents on the pulmonary vasculature was confirmed by echocardiographic measurements. Both agents were devoid of systemic side effects, since mean arterial pressure and systemic vascular resistance were not affected. A decrease in intrapulmonary shunt by inhalation of both agents was also demonstrated. Pulmonary vasodilatation attributed to iloprost seems to be of greater magnitude and of longer duration as compared to that of inhaled milrinone. Both substances proved to be selective pulmonary vasodilators. The greater magnitude and of longer duration vasodilatation attributed to iloprost may be due to its longer duration of action.

Postoperative Echocardiographic Reduction of Right Ventricular Function: Is Pericardial Opening Modality the Main Culprit?

Echocardiographic reduction of RV function, measured using TAPSE, is a well described phenomenon after cardiac surgery. The aim of the present study was to investigate the relation between the modality of pericardial opening (lateral versus anterior) and the postoperative right ventricular systolic function by comparing echocardiographic parameters in patients undergoing minimally invasive or traditional mitral valve repair. 34 patients with severe mitral regurgitation due to mitral valve prolapse underwent traditional (sternotomy) operation (Group A) or minimally invasive surgery with right anterolateral thoracotomy (Group B). A postoperative TAPSE fall was found in both groups. Group A experienced a significant postoperative TAPSE fall versus Group B with p < 0.0001.

Assessment of the effect of off-pump coronary artery bypass (OPCAB) surgery on right ventricle function using strain and strain rate imaging

BACKGROUND

Right ventricle function significantly decreases after coronary artery bypass surgery; as one of the likely causes, such a condition is attributed to the use of cardiopulmonary pump (CPB). Because nowadays there is a tendency toward increasing use of off-pump coronary artery bypass (OPCAB) surgery, this study was conducted to evaluate the right ventricle function after this type of surgery using strain and strain rate imaging (SRI) echocardiography.

METHODS

This study was conducted on 30 patients, candidate for elective OPCAB surgery, between 2011 and 2012. Standard echocardiography was performed before the surgery and the right ventricle function was examined using strain and SRI echocardiography. Then patient underwent surgery, 6 days and 3 months after surgery they underwent echocardiography again and the results obtained from the three stages were compared with each other.

RESULTS

Participants included 30 patients (23 males and 7 females) with a mean age of 66±11 years. Compared to the prior of the surgery, 6 days and 3 months after the surgery there was a significant decrease in tricuspid annular plane systolic excursion (TAPSE), tissue Doppler imaging (TDI) at the lateral annulus of tricuspid valve, and strain and SRI of right ventricle. However, the values obtained 3 months after surgery were significantly higher than those obtained after 6 days. In other words, the right ventricle function 6 days after the surgery had dropped, however some of the values recovered 3 months after the surgery.

CONCLUSIONS

The findings of this study are consistent with other studies in this field and showed that after coronary artery surgery a decline occurs in right ventricular function. However, more detailed quantitative strain and SRI parameters which were measured in our study showed that at the early days after the OPCAB surgery there is a decline in the right ventricle function which is relatively reversible at longer intervals (3 months after surgery).

Management of right heart failure in the critically ill

Right ventricular failure complicates several commonly encountered conditions in the intensive care unit. Right ventricular dilation and paradoxic movement of the interventricular septum on echocardiography establishes the diagnosis. Right heart catheterization is useful in establishing the specific cause and aids clinicians in management. Principles of treatment focus on reversal of the underlying cause, optimization of right ventricular preload and contractility, and reduction of right ventricular afterload. Mechanical support with right ventricular assist device or veno-arterial extracorporeal membrane oxygenation can be used in select patients who fail to improve with optimal medical therapy.

Peri-operative assessment of right heart function: role of echocardiography

The right heart contributes significantly to overall cardiac function. Right ventricular (RV) haemodynamics and function have been defined to be physiologically different from the left ventricle, and yet independently associated with outcomes in a spectrum of conditions. In particular, RV function has been shown to influence prognosis of patients undergoing surgery. The assessment of right heart function during the intra-operative and immediate postoperative periods plays an important role in the clinical management of patients having surgery. While a number of techniques are available for the assessment of the right heart intra-operatively, echocardiography remains the prime choice being least invasive, relatively safe, readily accessible and cost-effective. Advancements in the field of echocardiographic have improved ability to assess right heart function. This review examines the role echocardiography and advances in this imaging modality in the assessment of right heart function within the peri-operative setting.

Right Ventricular Depression After Cardiopulmonary Bypass for Valvular Surgery

OBJECTIVE

To assess if right ventricular (RV) dysfunction is associated with increased mortality after cardiac surgery.

DESIGN

Post-hoc analysis of a single-center double-blind randomized controlled trial.

SETTING

University hospital.

PARTICIPANTS

A total of 120 patients undergoing simple or complex valvular surgery.

INTERVENTIONS

Patients were randomized to receive intravenous amiodarone or placebo intraoperatively. As secondary analysis, patients were divided into those requiring or not requiring postoperative inotropic agents.

MEASUREMENTS AND MAIN RESULTS

After cardiopulmonary bypass (CPB), there were significant increases in heart rate, cardiac index, systolic and mean arterial pressures, central venous pressure and pulmonary capillary wedge pressure with reduction in systemic vascular resistance (p<0.05). Right ventricular end-systolic area became larger in those without inotropes and tricuspid annular plane systolic excursion was reduced in all patients; mitral annular systolic velocities were higher in patients receiving inotropes. Both right- and left-sided Doppler signals were altered significantly after CPB, which may be attributed to increased filling pressure. Inotropic agents were required in 56 patients after CPB (47%). The use of inotropic agents was associated with increased left and right atrial velocities (p<0.05). There were no differences in postoperative complications between groups; however, the number of deaths at 6 years was increased in patients who received inotropes after CPB (p = 0.0247).

CONCLUSIONS

The increases in right-sided dimensions after CPB are associated with reduction in RV function and increased biventricular filling pressure, suggesting worsening biventricular function and interventricular dependence. Inotropic medications were associated with unaltered RV dimensions and increased biatrial activity.

Innovative approaches in the perioperative care of the cardiac surgical patient in the operating room and intensive care unit

Perioperative care for cardiac surgery is undergoing rapid evolution. Many of the changes involve the application of novel technologies to tackle common challenges in optimizing perioperative management. Herein, we illustrate recent advances in perioperative management by focusing on a number of novel components that we judge to be particularly important. These include: the introduction of brain and somatic oximetry; transesophageal echocardiographic hemodynamic monitoring and bedside focused ultrasound; ultrasound-guided vascular access; point-of-care coagulation surveillance; right ventricular pressure monitoring; novel inhaled treatment for right ventricular failure; new approaches for postoperative pain management; novel approaches in specialized care procedures to ensure quality control; and specific approaches to optimize the management for postoperative cardiac arrest. Herein, we discuss the reasons that each of these components are particularly important in improving perioperative care, describe how they can be addressed, and their impact in the care of patients who undergo cardiac surgery.

Update on Perioperative Right Heart Assessment Using Transesophageal Echocardiography

Purpose of the review. This review aims to summarize recent findings relevant for perioperative 2- and 3-dimensional imaging of the right heart with transesophageal echocardiography. Special attention is given to developments that are likely to affect future approaches for prevention and therapy of perioperative right heart failure. Recent findings. Three-dimensional transesophageal echocardiography techniques are becoming more common for the evaluation of anatomy, volumes, and functional indices. Summary. Right heart failure continues to contribute to morbidity and mortality in the context of cardiothoracic surgery. The advent and widespread clinical use of innovative tools permitting more accurate echocardiographic assessment of the right heart will open the door to renewed interest in novel therapeutic strategies.

Perioperative right ventricular dysfunction

PURPOSE OF REVIEW

To evaluate new information on the importance of right ventricular function, diagnosis and management in cardiac surgical patients.

RECENT FINDINGS

There is growing evidence that right ventricular function is a key determinant in survival in cardiac surgery, particularly in patients with pulmonary hypertension. The diagnosis of this condition is helped by the use of specific hemodynamic parameters and echocardiography. In that regard, international consensus guidelines on the echocardiographic assessment of right ventricular function have been recently published. New monitoring modalities in cardiac surgery such as regional near-infrared spectroscopy can also assist management. Management of right ventricular failure will be influenced by the presence or absence of myocardial ischemia and left ventricular dysfunction. The differential diagnosis and management will be facilitated using a systematic approach.

SUMMARY

The use of right ventricular pressure monitoring and the publications of guidelines for the echocardiographic assessment of right ventricular anatomy and function allow the early identification of right ventricular failure. The treatment success will be associated by optimization of the hemodynamic, echocardiographic and near-infrared spectroscopy parameters.

Feasibility and efficacy of bypassing the right ventricle and pulmonary circulation to treat right ventricular failure: an experimental study

Background

Right ventricular failure (RVF) and -support is associated with poor results. We aimed for a new approach of right - sided assistance bypassing the right ventricle and pulmonary circulation in order to better decompress the right ventricle and optimize left ventricular filling.

Methods

From a microaxial pump (Abiomed), a low resistance oxygenator (Maquet and Novalung) and two cannulas (28 and 27 Fr) a system was set up and evaluated in an ovine model (n = 7). Connection with the heart was the right and left atrium. One hour the system was operated without RVF and turned of again. Then a RVF was induced and the course with the system running was evaluated. Complete hemodynamic monitoring was performed as well as echocardiography, flow measurement and blood gas analysis.

Results

The overall performance of the system was reliable. Without RVF no relevant changes of hemodynamics occurred; blood gases were supra normal. In RVF a cardiogenic shock developed (MAP 35 ± 13 mmHg, CO 1,1 ± 0,7 l/min). Immediately after starting the system the circulation normalized (significant increase of MAP to 85 ± 13 mmHg, of CO to 4,5 ± 1,9). Echocardiography also revealed right ventricular recovery. After stopping the system, RVF returned.

Conclusions

Bypassing the right ventricle and pulmonary circulation with an oxygenating assist device, which may offer the advantages of enhanced right ventricular decompression and augmented left atrial filling, is feasible and effective in the treatment of acute RVF. Long time experiments are needed.

Acute pressure overload of the right ventricle. Comparison of two models of right-left shunt. Pulmonary artery to left atrium and right atrium to left atrium: experimental study

Abtract

Pulmonary hypertension in cardiac surgery

Pulmonary hypertension is an important prognostic factor in cardiac surgery associated with increased morbidity and mortality. With the aging population and the associated increase severity of illness, the prevalence of pulmonary hypertension in cardiac surgical patients will increase. In this review, the definition of pulmonary hypertension, the mechanisms and its relationship to right ventricular dysfunction will be presented. Finally, pharmacological and non-pharmacological therapeutic and preventive approaches will be presented.

Intraoperative Hemodynamic Instability During and After Separation From Cardiopulmonary Bypass

Every year, more than 1 million patients worldwide undergo cardiac surgery. Because of the aging of the population, cardiac surgery will increasingly be offered to patients at a higher risk of complications. The consequence is a reduced physiological reserve and hence an increased risk of mortality. These issues will have a significant impact on future health care costs because the population undergoing cardiac surgery will be older and more likely to develop postoperative complications. One of the most dreaded complications in cardiac surgery is difficult separation from cardiopulmonary bypass (CPB). When separation from CPB is associated with right-ventricular failure, the mortality rate will range from 44% to 86%. Therefore, the diagnosis and the preoperative prediction of difficult separation from CPB will be crucial to improve the selection and care of patients and to prevent complications for this high-risk patient population.

Clinical review: practical recommendations on the management of perioperative heart failure in cardiac surgery

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.

Postoperative Care of the Cardiac Surgical Patient

The subspecialty of interventional cardiology began in 1977. Since then, the discipline of interventional cardiology has matured rapidly, particularly with regards to ischemic heart disease. As a result, more patients are undergoing percutaneous catheter interventional therapy for ischemic heart disease and fewer patients are undergoing surgical myocardial revascularization. Those patients referred for surgical revascularization are generally older and have more complex problems. Furthermore, as the population ages more patients are referred to surgery for valvular heart disease. The result of these changes is a population of surgical patients older and sicker than previously treated.