Predictors of inotrope use in patients undergoing concomitant coronary artery bypass graft (CABG) and aortic valve replacement (AVR) surgeries at separation from cardiopulmonary bypass (CPB)

Association between preoperative right heart catheterization parameters and outcomes in patients undergoing isolated coronary artery bypass grafting

Right ventricular catheterization may capture information that can help define prognosis before coronary artery bypass grafting (CABG). In this study, we evaluate the association between preoperative right heart catheterization parameters and outcomes of patients undergoing isolated CABG. All patients undergoing isolated CABG at our institution from 2013 to 2021 who also underwent preoperative right heart catheterization <14 days prior to isolated CABG were retrospectively queried. A total of 2343 patients underwent isolated CABG of whom 78 patients [20 (25.6%) female] were included in the final analysis. On multivariable regression, central venous pressure was significantly associated with operative mortality (odds ratio 1.14, 95% confidence interval 1.02-1.27, P = 0.024). Preoperative cardiac index was significantly inversely associated with intensive care unit length of stay (odds ratio 0.72, 95% confidence interval 0.62-0.84, P < 0.001) and duration of inotropic support (odds ratio 0.76, 95% confidence interval 0.63-0.92, P < 0.01). Assessment of preoperative cardiac function by right heart catheterization should be considered in high-risk patient populations, particularly those who have significant left ventricular dysfunction on preoperative echocardiography that would make them candidate for percutaneous coronary intervention, left ventricular assist device or heart transplantation. Further, right heart catheterization can help to guide preoperative optimization and intra-/postoperative decision-making.

Application of a simplified transesophageal echocardiography examination sequence in high-risk cardiac surgery

BACKGROUND

In cardiac surgical procedures, patients carrying high-risk profiles are prone to encompass complicated cardiopulmonary bypass (CPB) separation. Intraoperative transesophageal echocardiography (TEE), a readily available tool, is utilized to detect cardiac structural and functional pathologies as well as to facilitate clinical management of CPB separation, especially in the episodes of hemodynamic compromise. However, the conventional TEE examination, always performed in a liberal fashion without any restriction of view acquisition, is relatively time-consuming; there appear its flaws in the context of critically severe status. We therefore developed the perioperative rescue transesophageal echocardiography (PReTEE), a simplified three-view TEE protocol consisting of midesophageal four chamber, midesophageal left ventricular long axis, and transgastric short axis.

METHODS

This is a single-center and randomized controlled trial which will be implemented in Peking Union Medical College Hospital, Beijing, China. A total of 46 TEE scans are schemed to be performed by 6 operators participating in and randomly assigned to either the PReTEE or the conventional TEE group. This study is purposed to investigate whether the efficiency of discriminating leading causes of difficult CPB wean-off can be significantly improved via an abbreviated sequence of TEE views. The primary outcome of interest is the difference between the groups of PReTEE and the conventional TEE in the successful discrimination of etiologies in specified 120 s. Cox proportional hazards model will be further employed to calculate the outcome difference.

DISCUSSION

The estimated results of this trial are oriented at verifying whether a simplified TEE exam sequence can improve the efficiency of etiologies discrimination during CPB separation in cardiac surgery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05960552. Registered on 6 July 2023.

Determinants of 30-day mortality in elderly patients admitted to a cardiovascular surgery intensive care unit

BACKGROUND

This study aims to identify the factors influencing 30-day morbidity and mortality in patients aged 65 and older undergoing cardiovascular surgery.

METHODS

Data from 360 patients who underwent cardiac surgery between January 2012 and August 2021 in the Cardiovascular Surgery Intensive Care Unit (CVS ICU) were analyzed. Patients were categorized into two groups: "mortality+" (33 patients) and "mortality-" (327 patients). Factors influencing mortality, including preoperative, intraoperative, and postoperative risk factors, complications, and outcomes, were assessed.

RESULTS

Significant differences were observed between the two groups in factors affecting mortality, including extubation time, ICU stay duration, blood transfusion, surgical reexploration, aortic clamp duration, glomerular filtration rate (GFR), blood urea nitrogen (BUN), creatinine, hemoglobin A1c (HbA1c) levels, and the lowest systolic blood pressure during the first 24 hours in the ICU (p<0.05). The "mortality+" group had longer extubation times and ICU stays, required more blood transfusions, and had higher BUN-creatinine ratios, but lower systolic blood pressures, GFR, and HbA1c levels. Mortality was also higher in patients needing noradrenaline infusions and those who underwent reoperation for bleeding (p<0.05).

CONCLUSION

By optimizing preoperative renal function, minimizing extubation time, shortening ICU stays, and carefully managing blood transfusions, surgical reexplorations, aortic clamp duration, and HbA1c levels, we believe that the mortality rate can be reduced in elderly patients. Key strategies include shortening aortic clamp times, reducing perioperative blood transfusions, and ensuring effective bleeding control.

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.

The effect of calcium gluconate administration during cardiopulmonary bypass on hemodynamic variables in infants undergoing open-heart surgery

Background

The incidence of complications after heart surgery is a critical factor in disability, deaths, lengthening hospital stays, and increasing treatment costs. The metabolic balance of certain hormones and electrolytes is necessary for proper cardiac function. In children, various biochemical conditions may cause calcium depletion during heart surgery. The purpose of this study was to determine the effect of calcium gluconate administration during cardiopulmonary bypass on hemodynamic variables and clinical outcomes in infants undergoing open-heart surgery. This study was conducted at Rajaie Cardiovascular Medical and Research Center in 2021 using a controlled randomized clinical trial. A total of 60 patients with open-heart surgery weighing up to 10 kg were included in the study. The first group received an intravenous injection of calcium gluconate 20 min after opening the aortic clamp, and the second group was monitored as a control group. Data collection tools included checklists containing demographics, surgical information, and intensive care unit measures.

Results

The Chi-square test or Fisher's exact test showed that the frequency distribution of gender, blood group, Rhesus factor (RH), and clinical diagnosis in the two groups of intervention and control was not statistically significant (p < 0.05). The mean and standard deviation of Ejection Fraction (EF) changes (before and after) were 13.27 ± 9.16 in the intervention group and 8.31 ± 9.80 in the control group (p = 0.065). The results of two-way repeated measures ANOVA showed that mean systolic blood pressure (p = 0.030), mean diastolic blood pressure (p = 0.021), mean heart rate (p = 0.025), mean arterial pressure (p = 0.020), mean pH (p < 0.001), and mean hemoglobin (p = 0.018) in the intervention, and control groups were statistically significant.

Conclusions

In the present study, unlike systolic pressure, mean diastolic blood pressure decreased, and mean arterial pressure increased significantly. As a result, the slope of changes during the study period was different in the intervention and control groups.

Impact of Processed Electroencephalography in Cardiac Surgery: A Retrospective Analysis

OBJECTIVE

The use of brain function monitoring with processed electroencephalography (pEEG) during cardiac surgery is gaining interest for the optimization of hypnotic agent delivery during the maintenance of anesthesia. The authors sought to determine whether the routine use of pEEG-guided anesthesia is associated with a reduction of hemodynamic instability during cardiopulmonary bypass (CPB) separation and subsequently reduces vasoactive and inotropic requirements in the intensive care unit.

DESIGN

This is a retrospective cohort study based on an existing database.

SETTING

A single cardiac surgical center.

PARTICIPANTS

Three hundred patients undergoing cardiac surgery, under CPB, between December 2013 and March 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred and fifty patients had pEEG-guided anesthesia, and 150 patients did not have a pEEG-guided anesthesia. Multiple logistic regression demonstrated that pEEG-guided anesthesia was not associated with a successful CPB separation (p = 0.12). However, the use of pEEG-guided anesthesia reduced by 57% the odds of being in a higher category for vasoactive inotropic score compared to patients without pEEG (odds ratio = 0.43; 95% confidence interval: 0.26-0.73; p = 0.002). Duration of mechanical ventilation, fluid balance, and blood losses were also reduced in the pEEG anesthesia-guided group (p < 0.003), but there were no differences in organ dysfunction duration and mortality.

CONCLUSION

During cardiac surgery, pEEG-guided anesthesia allowed a reduction in the use of inotropic or vasoactive agents at arrival in the intensive care unit. However, it did not facilitate weaning from CPB compared to a group where pEEG was unavailable. A pEEG-guided anesthetic management could promote early vasopressor weaning after cardiac surgery.

Use of Vasoactive Medications after Cardiac Surgery in the United States

Rationale: Patients undergoing cardiac surgery often require vasopressor or inotropic ("vasoactive") medications, but patterns of postoperative use are not well described.Objectives: This study aimed to describe vasoactive medication administration throughout hospitalization for cardiac surgery, to identify patient- and hospital-level factors associated with postoperative use, and to quantify variation in treatment patterns among hospitals.Methods: Retrospective study using the Premier Healthcare Database. The cohort included adult patients who underwent coronary artery bypass grafting or open valve repair or replacement (or in combination) from January 1, 2016, to June 30, 2018. Primary outcome was receipt of vasoactive medication(s) on the first postoperative day (POD1). We identified patient- and hospital-level factors associated with receipt of vasoactive medications using multilevel mixed-effects logistic regression modeling. We calculated adjusted median odds ratios to determine the extent to which receipt of vasoactive medications on POD1 was determined by each hospital, then calculated quotients of Akaike Information Criteria to compare the relative contributions of patient and hospital characteristics and individual hospitals with observed variation.Results: Among 104,963 adults in 294 hospitals, 95,992 (92.2%) received vasoactive medication(s) during hospitalization; 30,851 (29.7%) received treatment on POD1, most commonly norepinephrine (n = 11,427, 37.0%). A median of 29.0% (range, 0.0-94.4%) of patients in each hospital received vasoactive drug(s) on POD1. After adjustment, hospital of admission was associated with twofold increased odds of receipt of any vasoactive medication on POD1 (adjusted median odds ratio, 2.07; 95% confidence interval, 1.93-2.21). Admitting hospital contributed more to observed variation in POD1 vasoactive medication use than patient or hospital characteristics (quotients of Akaike Information Criteria 0.58, 0.44, and <0.001, respectively).Conclusions: Nearly all cardiac surgical patients receive vasoactive medications during hospitalization; however, only one-third receive treatment on POD1, with significant variability by institution. Further research is needed to understand the causes of variability across hospitals and whether these differences are associated with outcomes.

A Descriptive Study of Perioperative Hemodynamics in Open Cardiac Surgery Patients

OBJECTIVES

The purpose of the present study was to describe how the perioperative hemodynamic profile before and after cardiopulmonary bypass during cardiac surgery is influenced by age and to describe the association between postoperative hemodynamics and one-year mortality.

DESIGN

A retrospective registry-based study.

SETTING

University Hospital of Aarhus, Denmark.

PARTICIPANTS

The study comprised 6,595 patients undergoing elective on-pump cardiac surgery from 2006 to 2016.

MEASUREMENTS AND MAIN RESULTS

Perioperative hemodynamic values were derived from computerized anesthesia and intensive care reports, including mean arterial pressure, cardiac index, and oxygenation saturation from mixed venous blood in the pulmonary artery, during the perioperative period. Perioperative hemodynamic values were stratified according to age. Logistic regression was applied to predict the crude probability of death within one year from surgery according to hemodynamic values at six hours after surgery, stratified by age and use of inotropic agents, respectively. Lower values for cardiac index and mixed venous blood in the pulmonary artery with increasing age, across all points in time in the perioperative course, were observed. Higher probability of death was associated with lower hemodynamic values in the postoperative phase, and the probability of death was modified by age and the need for inotropic agents.

DISCUSSION

This is a large registry based study describing the perioperative hemodynamic profile of patients undergoing cardiac surgery and the results enhance our understanding of age-differentiated values of CI and SvO2 in this specific population.

Ministernotomy or sternotomy in isolated aortic valve replacement? Early results

Introduction

Aortic valve replacement (AVR) is the gold standard in treating symptomatic aortic valve defects. To improve the healing process and limit the trauma, the minimally invasive approach was introduced.

Aim

To compare the peri- and post-operative results of aortic valve replacement performed via conventional full sternotomy (con-AVR) and of AVR performed via partial upper sternotomy (mini-AVR).

Material and methods

The total study population was divided into 2 demographically homogeneous groups: mini-AVR (n = 74) and con-AVR (n = 76). There were no statistically significant differences in preoperative echocardiography.

Results

Aortic cross-clamp time and cardiopulmonary bypass time were significantly longer in the mini-AVR group. Shorter mechanical ventilation time, hospital stay and lower postoperative drainage were observed in the mini-AVR group (p < 0.05). Biological prostheses were more frequently implanted in the mini-AVR group (p < 0.05). Patients from the mini-AVR group reported less postoperative pain. No significant differences were found in the diameter of the implanted aortic prosthesis, the amount of inotropic agents and painkillers, postoperative left ventricular ejection fraction (LVEF), medium and maximum transvalvular gradient or the number of transfused blood units. There were no differences in the frequency of postoperative complications such as mortality, stroke, atrial fibrillation, renal failure, wound infection, sternal instability, or the need for rethoracotomy.

Conclusions

Ministernotomy for AVR is a safe method and does not increase morbidity and mortality. It significantly reduces post-operative blood loss and shortens hospital stay. Ministernotomy can be successfully used as an alternative method to sternotomy.

Beneficial effects of levosimendan on survival in patients undergoing extracorporeal membrane oxygenation after cardiovascular surgery

BACKGROUND

The impact of levosimendan treatment on clinical outcome in patients undergoing extracorporeal membrane oxygenation (ECMO) support after cardiovascular surgery is unknown. We hypothesized that the beneficial effects of levosimendan might improve survival when adequate end-organ perfusion is ensured by concomitant ECMO therapy. We therefore studied the impact of levosimendan treatment on survival and failure of ECMO weaning in patients after cardiovascular surgery.

METHODS

We enrolled a total of 240 patients undergoing veno-arterial ECMO therapy after cardiovascular surgery at a university-affiliated tertiary care centre into our observational single-centre registry.

RESULTS

During a median follow-up period of 37 months (interquartile range 19-67 months), 65% of patients died. Seventy-five per cent of patients received levosimendan treatment within the first 24 h after initiation of ECMO therapy. Cox regression analysis showed an association between levosimendan treatment and successful ECMO weaning [adjusted hazard ratio (HR) 0.41; 95% confience interval (CI) 0.22-0.80; P=0.008], 30 day mortality (adjusted HR 0.52; 95% CI 0.30-0.89; P=0.016), and long-term mortality (adjusted HR 0.64; 95% CI 0.42-0.98; P=0.04).

CONCLUSIONS

These data suggest an association between levosimendan treatment and improved short- and long-term survival in patients undergoing ECMO support after cardiovascular surgery.

Early High-Volume Hemofiltration versus Standard Care for Post-Cardiac Surgery Shock. The HEROICS Study

RATIONALE

Post-cardiac surgery shock is associated with high morbidity and mortality. By removing toxins and proinflammatory mediators and correcting metabolic acidosis, high-volume hemofiltration (HVHF) might halt the vicious circle leading to death by improving myocardial performance and reducing vasopressor dependence.

OBJECTIVES

To determine whether early HVHF decreases all-cause mortality 30 days after randomization.

METHODS

This prospective, multicenter randomized controlled trial included patients with severe shock requiring high-dose catecholamines 3-24 hours post-cardiac surgery who were randomized to early HVHF (80 ml/kg/h for 48 h), followed by standard-volume continuous venovenous hemodiafiltration (CVVHDF) until resolution of shock and recovery of renal function, or conservative standard care, with delayed CVVHDF only for persistent, severe acute kidney injury.

MEASUREMENTS AND MAIN RESULTS

On Day 30, 40 of 112 (36%) HVHF and 40 of 112 (36%) control subjects (odds ratio, 1.00; 95% confidence interval, 0.64-1.56; P = 1.00) had died; only 57% of the control subjects had received renal-replacement therapy. Between-group survivors' Day-60, Day-90, intensive care unit, and in-hospital mortality rates, Day-30 ventilator-free days, and renal function recovery were comparable. HVHF patients experienced faster correction of metabolic acidosis and tended to be more rapidly weaned off catecholamines but had more frequent hypophosphatemia, metabolic alkalosis, and thrombocytopenia.

CONCLUSIONS

For patients with post-cardiac surgery shock requiring high-dose catecholamines, the early HVHF onset for 48 hours, followed by standard volume until resolution of shock and recovery of renal function, did not lower Day-30 mortality and did not impact other important patient-centered outcomes compared with a conservative strategy with delayed CVVHDF initiation only for patients with persistent, severe acute kidney injury. Clinical trial registered with www.clinicaltrials.gov (NCT 01077349).

Does Parsonnet scoring model predict mortality following adult cardiac surgery in India?

Aims and Objectives:

To validate the Parsonnet scoring model to predict mortality following adult cardiac surgery in Indian scenario.

Materials and Methods:

A total of 889 consecutive patients undergoing adult cardiac surgery between January 2010 and April 2011 were included in the study. The Parsonnet score was determined for each patient and its predictive ability for in-hospital mortality was evaluated. The validation of Parsonnet score was performed for the total data and separately for the sub-groups coronary artery bypass grafting (CABG), valve surgery and combined procedures (CABG with valve surgery). The model calibration was performed using Hosmer–Lemeshow goodness of fit test and receiver operating characteristics (ROC) analysis for discrimination. Independent predictors of mortality were assessed from the variables used in the Parsonnet score by multivariate regression analysis.

Results:

The overall mortality was 6.3% (56 patients), 7.1% (34 patients) for CABG, 4.3% (16 patients) for valve surgery and 16.2% (6 patients) for combined procedures. The Hosmer–Lemeshow statistic was <0.05 for the total data and also within the sub-groups suggesting that the predicted outcome using Parsonnet score did not match the observed outcome. The area under the ROC curve for the total data was 0.699 (95% confidence interval 0.62–0.77) and when tested separately, it was 0.73 (0.64–0.81) for CABG, 0.79 (0.63–0.92) for valve surgery (good discriminatory ability) and only 0.55 (0.26–0.83) for combined procedures. The independent predictors of mortality determined for the total data were low ejection fraction (odds ratio [OR] - 1.7), preoperative intra-aortic balloon pump (OR - 10.7), combined procedures (OR - 5.1), dialysis dependency (OR - 23.4), and re-operation (OR - 9.4).

Conclusions:

The Parsonnet score yielded a good predictive value for valve surgeries, moderate predictive value for the total data and for CABG and poor predictive value for combined procedures.

Clinical practice in perioperative monitoring in adult cardiac surgery: is there a standard of care? Results from an national survey

This study was to investigate and define what is considered as a current clinical practice in hemodynamic monitoring and vasoactive medication use after cardiac surgery in Italy. A 33-item questionnaire was sent to all intensive care units (ICUs) admitting patients after cardiac surgery. 71 out of 92 identified centers (77.2 %) returned a completed questionnaire. Electrocardiogram, invasive blood pressure, central venous pressure, pulse oximetry, diuresis, body temperature and blood gas analysis were identified as routinely used hemodynamic monitoring, whereas advanced monitoring was performed with pulmonary artery catheter or echocardiography. Crystalloids were the fluids of choice for volume replacement (86.8 % of Centers). To guide volume management, central venous pressure (26.7 %) and invasive blood pressure (19.7 %) were the most frequently used parameters. Dobutamine was the first choice for treatment of left heart dysfunction (40 %) and epinephrine was the first choice for right heart dysfunction (26.8 %). Half of the Centers had an internal protocol for vasoactive drugs administration. Intra-aortic balloon pump and extra-corporeal membrane oxygenation were widely available among Cardiothoracic ICUs. Angiotensin-converting enzyme inhibitors were suspended in 28 % of the Centers. The survey shows what is considered as standard monitoring in Italian Cardiac ICUs. Standard, routinely used monitoring consists of ECG, SpO2, etCO2, invasive BP, CVP, diuresis, body temperature, and BGA. It also shows that there is large variability among the various Centers regarding hemodynamic monitoring of fluid therapy and inotropes administration. Further research is required to better standardize and define the indicators to improve the standards of intensive care after cardiac surgery among Italian cardiac ICUs.

Early levosimendan administration is associated with decreased mortality after cardiac surgery

PURPOSE

The aim of this study was to assess the effects on postoperative outcome of levosimendan with respect to timing of its administration in cardiac surgery patients.

MATERIALS AND METHODS

Levosimendan administration was triggered by a severely reduced left ventricular systolic function (left ventricular ejection fraction, <35%) and/or signs of a low cardiac output syndrome. A total of 159 patients were retrospectively assigned depending on an early (perioperatively up to the first hour after intensive care unit [ICU] admission) vs late (later than the first hour after ICU admission) start of treatment.

RESULTS

Patients receiving levosimendan after the first hour of ICU admission (n = 89) had a significantly increased inhospital (P = .004) and 1-year (P = .027) mortality. Duration of mechanical ventilation (P = .002), incidence of renal dysfunction (P = .002), and need of renal replacement therapy (P = .032) were significantly increased in the late start group. A late start of levosimendan treatment was associated with an odds ratio of 2.258 (95% confidence interval, 1.139-4.550; P = .021) for inhospital mortality and an adjusted hazard ratio of 1.827 (95% confidence interval, 1.155-2.890; P = .010) for 1-year survival.

CONCLUSIONS

Findings of this retrospective analysis favor an "early," that is, intraoperatively up to the first hour after ICU admission, start of perioperative levosimendan treatment to maximize its ability to reduce mortality and morbidity.

Early administration of levosimendan is associated with improved kidney function after cardiac surgery - a retrospective analysis

BACKGROUND

Several animal studies suggest beneficial effects on kidney function upon administration of levosimendan. As recent data from clinical studies are heterogeneous, we sought to investigate whether levosimendan is associated with improved postoperative kidney function in cardiac surgery patients with respect to timing of its administration.

METHODS

Retrospective, single centre, observational analysis at a university hospital in Berlin, Germany. All adult patients without preoperative renal dysfunction that underwent coronary artery bypass grafting and/or valve reconstruction/replacement between 01/01/2007 and 31/12/2011 were considered for analyses.

RESULTS

Out of 1.095 included patients, 46 patients were treated with levosimendan due to a severely reduced left ventricular systolic function preoperatively (LVEF < 35%) and/or clinical signs of a low cardiac output syndrome. Sixty-one percent received the drug whilst in the OR, 39% after postoperative intensive care unit admission. When levosimendan was given immediately after anaesthesia induction, creatinine plasma levels (p = 0.009 for nonparametric analysis of longitudinal data in a two-factorial design) and incidence of postoperative renal dysfunction (67.9% vs. 94.4%; p = 0.033) were significantly reduced in contrast to a later start of treatment. In addition, duration of renal replacement therapy was significantly shorter (79 [35;332] vs. 272 [132;703] minutes; p = 0.046) in that group.

CONCLUSIONS

Postoperative kidney dysfunction is a common condition in patients under going cardiac surgery. Patients with severely reduced left ventricular function and/or clinical signs of a low cardiac output syndrome who preoperatively presented with a normal kidney function may benefit from an early start of levosimendan administration, i.e. immediately after anaesthesia.

TRIAL REGISTRATION

Clinicaltrials.gov-ID: NCT01918618 .

Health Outcomes with and without Use of Inotropic Therapy in Cardiac Surgery

Background:

Inotropes used to obtain short-term hemodynamic benefits in cardiac surgery may carry a risk of increased myocardial ischemia and adverse outcomes. This study investigated the association between intra- and postoperative use of inotropes and mortality and postoperative complications.

Methods:

A historic cohort study using prospective data from the Western Denmark Heart Registry on 6,005 consecutive cardiac surgery cases from three university hospitals. Propensity matching on pre- and intraoperative variables was used to identify a subgroup of patients receiving inotropic therapy (n = 1,170) versus comparable nonreceivers (n = 1,170) for outcome analysis.

Results:

Two thousand ninety-seven patients (35%) received inotropic therapy; 3,908 (65%) did not receive any inotropic or vasopressor support perioperatively. Among propensity-matched cohort including 2,340 patients 30-day mortality was 3.2% and 1-yr mortality was 7.6%. In the matched cohort, patients exposed to inotropes had a higher 30-day mortality (adjusted hazards ratio, 3.7; 95% CI, 2.1 to 6.5) as well as a higher 1-yr mortality rate (adjusted hazards ratio, 2.5; 95% CI, 1.8 to 3.5) compared with nonreceivers. Among propensity-matched, the following absolute events rates were observed: myocardial infarction 2.4%, stroke 2.8%, arrhythmia 35%, and renal replacement therapy 23.9%. Inotropic therapy was independently associated with postoperative myocardial infarction (adjusted odds ratio, 2.1; 95% CI, 1.4 to 3.0), stroke (adjusted odds ratio, 2.4; 95% CI, 1.4 to 4.3), and renal replacement therapy (adjusted odds ratio, 7.9; 95% CI, 3.8 to 16.4).

Conclusion:

Use of intra- and postoperative inotropes was associated with increased mortality and major postoperative morbidity.

Influence of levosimendan on organ dysfunction in patients with severely reduced left ventricular function undergoing cardiac surgery

OBJECTIVES

Levosimendan is an inotropic drug with organ-protective properties due to its activation of mitochondrial K(ATP) channels. This prospective, randomized, double-blind, placebo-controlled study investigated whether administration of levosimendan prior to cardiopulmonary bypass could reduce organ dysfunction and influence subsequent secondary endpoints.

PATIENTS AND METHODS

Patients with left ventricular ejection fraction <30% scheduled for elective coronary artery bypass surgery (with or without valve surgery) received either levosimendan (12.5 mg, 0.1 µg kg(-1) per min; n = 17) or placebo (n = 16) central venous infusion, immediately after anaesthesia induction, as add-on medication to a goal-orientated treatment algorithm.

RESULTS

A total of 33 patients completed the study. There were no statistically significant differences in Sequential Organ Failure Assessment scores, survival, haemodynamic parameters, time to extubation, time in intensive care unit, need for haemodialysis or health-related quality-of-life at 6 months post operation. The levosimendan group compared with the placebo group had significantly lower use of epinephrine (35% versus 81%) and nitroglycerine (6% versus 44%) 24 h postoperation, and significantly less frequent serious adverse events (13% versus 47%).

CONCLUSIONS

These preliminary results show that timely perioperative levosimendan treatment is feasible, has a favourable safety profile safe and may help to prevent low cardiac output syndrome. However, organ function was not preserved. Further studies, using larger sample sizes, are required.

Left ventricular end-diastolic pressure as an independent predictor of outcome during balloon aortic valvuloplasty

OBJECTIVES

In this study, we examined the predictive value of the left ventricular end-diastolic pressure (LVEDP) in patients undergoing balloon aortic valvuloplasty (BAV).

BACKGROUND

The LVEDP is a useful indicator of hemodynamic status in patients with severe aortic stenosis. In BAV, decompensated heart failure is associated with worse outcomes.

METHODS

We identified all consecutive patients with severe symptomatic aortic stenosis who underwent retrograde BAV at the Massachusetts General Hospital from 2004 to 2008. Patients were stratified and compared according to their baseline LVEDP into ≤15 mm Hg, 16-20 mm Hg, 21-25 mm Hg, and ≥26 mm Hg. Procedural and in-hospital outcomes and adverse events were compared. Multivariate logistic regression was used for the adjusted analysis.

RESULTS

A total of 111 patients with a mean age of 83±11 years underwent BAV. Of these, the LVEDP was ≤15 mm Hg in 29 (26%), 16-20 mm Hg in 41 (37%), 21-25 mm Hg in 16 (14%), and ≥26 mm Hg in 25 (23%) patients. Baseline characteristics were similar among the four groups. Noticeably, patients with high LVEDP levels had significantly higher rates of the combined endpoint of in-hospital death, myocardial infarction (MI), cardiopulmonary arrest, and tamponade was P = 0.02. Periprocedural MI was more common among those with higher LVEDP (16% vs. 2.3%; P = 0.04). Multivariate analysis revealed LVEDP (OR 1.08, for each mm Hg increase in pressure, 95 % CI 1.02-1.14), small LV chamber size, and New York Heart Association class as independent predictors of adverse outcomes.

CONCLUSIONS

The LVEDP is an important independent predictor of poor in-hospital outcome during BAV. In these patients, the immediate hemodynamic status may be more important than the baseline left ventricular systolic function. Hemodynamic optimization before or during BAV should be considered and may be beneficial.

Cardiac peroxisome proliferator-activated receptor δ (PPARδ) as a new target for increased contractility without altering heart rate

Background and Aims

Agents having a positive inotropic effect on the heart are widely used for the treatment of heart failure. However, these agents have the side effect of altering heart rate. It has been established that peroxisome proliferator-activated receptor δ (PPARδ) is mediated in cardiac contraction, however the effect on heart rate is unknown. Thus, we used an agonist of PPARδ, GW0742, to investigate this issue in the present study.

Methods and Results

We used isolated hearts in Langendorff apparatus and hemodynamic analysis in catheterized rats to measure the actions of GW0742 extra-vivo and in vivo. In diabetic rats with heart failure, GW0742 at a dose sufficient to activate PPARδ reversed cardiac contraction without changes in heart rate. In normal rats, PPARδ enhanced cardiac contractility and hemodynamic dP/dt_max significantly more than dobutamine. Both actions were diminished by GSK0660 at a dose enough to block PPARδ. However, GW0742 at the same dose failed to modify heart rate, although it did produce a mild increase in blood pressure. Detection of intracellular calcium level and Western blotting analysis showed that the intracellular calcium concentration and troponin I phosphorylation were both enhanced by GW0742.

Conclusion

Activation of PPARδ by GW0742 increases cardiac contractility but not heart rate. Thus, PPARδ may be a suitable target for the development of inotropic agents to treat heart failure without changing heart rate.

Postoperative inotrope and vasopressor use following CABG: outcome data from the CAPS-care study

BACKGROUND/AIM

Limited clinical data exist to guide practice patterns and evidence-based use of inotropes and vasopressors following coronary artery bypass grafting (CABG).

METHODS

Contemporary Analysis of Perioperative Cardiovascular Surgical Care (CAPS-Care) collected detailed perioperative data from 2390 CABG patients between 2004 and 2005 at 55 U.S. hospitals. High-risk elective or urgent CABG patients were eligible for inclusion. We stratified participating hospitals into high, medium, and low tertiles of inotrope use. Hospital-level outcomes were compared before and after risk adjustment for baseline characteristics.

RESULTS

Hospital-level risk-adjusted rates of any inotrope/vasopressor use varied from 100% to 35%. Hospitals in the highest tertile of use had more patients with mitral regurgitation compared to medium- or low-use hospitals (p < 0.001), more previous cardiovascular interventions (p = 0.002), longer cardiopulmonary bypass (p < 0.001), longer cross-clamp times (p < 0.001), and required more transfusions (p = 0.001). Despite these differences, unadjusted outcomes were similar between high-, medium-, and low-use hospitals for operative mortality (4.5% vs. 5.3% vs. 5.2%; p = 0.702), 30-day mortality (4.1% vs. 4.6% vs. 5.0%; p = 0.690), postoperative renal failure (7.2% vs. 9.2% vs. 6.6%; p = 0.142), atrial fibrillation (23.0% vs. 27.2% vs. 25.6%; p = 0.106), and acute limb ischemia (0.6% vs. 0.5% vs. 0.5%; p = 0.945). These similar outcomes persisted after risk adjustment: adjusted OR = 0.97 (95% CI [0.94, 1.00], p = 0.086) for operative mortality and adjusted OR = 1.00 (95% CI [0.96, 1.04], p = 0.974) for postoperative renal failure.

CONCLUSION

While considerable variability is present among hospitals in inotrope use following CABG, observational comparison of outcomes did not distinguish a superior pattern; thus, randomized prospective data are needed to better guide clinical practice.

The relationship between inotrope exposure, six-hour postoperative physiological variables, hospital mortality and renal dysfunction in patients undergoing cardiac surgery

Introduction

Acute haemodynamic complications are common after cardiac surgery and optimal perioperative use of inotropic agents, typically guided by haemodynamic variables, remains controversial. The aim of this study was to examine the relationship of inotrope use to hospital mortality and renal dysfunction.

Material and methods

A retrospective cohort study of 1,326 cardiac surgery patients was carried out at two university-affiliated ICUs. Multivariable logistic regression analysis and propensity matching were performed to evaluate whether inotrope exposure was independently associated with mortality and renal dysfunction.

Results

Patients exposed to inotropes had a higher mortality rate than those not exposed. After adjusting for differences in Parsonnet score, left ventricular ejection fraction, perioperative intraaortic balloon pump use, bypass time, reoperation and cardiac index, inotrope exposure appeared to be independently associated with increased hospital mortality (adjusted odds ratio (OR) 2.3, 95% confidence interval (95% CI) 1.2 to 4.5) and renal dysfunction (adjusted OR 2.7, 95% CI 1.5 to 4.6). A propensity score-matched analysis similarly demonstrated that death and renal dysfunction were significantly more likely to occur in patients exposed to inotropes (P = 0.01).

Conclusions

Postoperative inotrope exposure was independently associated with worse outcomes in this cohort study. Further research is needed to better elucidate the appropriate use of inotropes in cardiac surgery.

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.

Preoperative diastolic function predicts the onset of left ventricular dysfunction following aortic valve replacement in high-risk patients with aortic stenosis

INTRODUCTION

Left ventricular (LV) dysfunction frequently occurs after cardiac surgery, requiring inotropic treatment and/or mechanical circulatory support. In this study, we aimed to identify clinical, surgical and echocardiographic factors that are associated with LV dysfunction during weaning from cardiopulmonary bypass (CPB) in high-risk patients undergoing valve replacement for aortic stenosis.

METHODS

Perioperative data were prospectively collected in 108 surgical candidates with an expected operative mortality >or=9%. All anesthetic and surgical techniques were standardized. Reduced LV systolic function was defined by an ejection fraction <40%. Diastolic function of the LV was assessed using standard Doppler-derived parameters, tissue Doppler Imaging (TDI) and transmitral flow propagation velocity (Vp).

RESULTS

Doppler-derived pulmonary flow indices and TDI could not be obtained in 14 patients. In the remaining 94 patients, poor systolic LV was documented in 14% (n = 12) and diastolic dysfunction in 84% of patients (n = 89), all of whom had Vp <50 cm/s. During weaning from CPB, 38 patients (40%) required inotropic and/or mechanical circulatory support. By multivariate regression analysis, we identified three independent predictors of LV systolic dysfunction: age (Odds ratio [OR] = 1.11; 95% confidence interval (CI), 1.01 to 1.22), aortic clamping time (OR = 1.04; 95% CI, 1.00 to 1.08) and Vp (OR = 0.65; 95% CI, 0.52 to 0.81). Among echocardiographic measurements, Vp was found to be superior in terms of prognostic value and reliability. The best cut-off value for Vp to predict LV dysfunction was 40 cm/s (sensitivity of 72% and specificity 94%). Patients who experienced LV dysfunction presented higher in-hospital mortality (18.4% vs. 3.6% in patients without LV dysfunction, P = 0.044) and an increased incidence of serious cardiac events (81.6 vs. 28.6%, P < 0.001).

CONCLUSIONS

This study provides the first evidence that, besides advanced age and prolonged myocardial ischemic time, LV diastolic dysfunction characterized by Vp <or= 40 cm/sec identifies patients who will require cardiovascular support following valve replacement for aortic stenosis.