Inotropes and Vasopressors

Enhancing outcomes in Langendorff-perfused rodent hearts through perfusion parameter optimization

Despite important advancements in addressing cardiovascular diseases (CVDs), there has been an overall lack of progress in the field, leading to a slower decline in the rate of CVDs related deaths, and even an increase for some risk groups (e.g. increase in stroke mortality) exacerbated by an aging and obese population. While a multi-faceted problem, this deceleration may be influenced by the preferred model systems utilized in translation research. Cardiac cell lines, although easier to handle, lack biological accuracy due to the unnatural modifications required for successful culture and may not recapitulate complex 3-dimensional structural and environmental factors. At the same time, whole animal experimentation provides unwanted complexity during initial scientific development. Alternatively, ex vivo perfusion of isolated rodent hearts provides the needed biological accuracy with decreased organismal complexity. This platform facilitates the evaluation of the isolated heart, without neuro-reflexes and/or humoral contributions, unveiling the direct effects of stimuli in heart function/homeostasis. This manuscript leverages the wide array of perfusion parameters (i.e. perfusate, flow rate, coronary pressures), to demonstrate the capability of ex vivo heart perfusion protocols to accommodate a large range of experimental needs. Through this work, it was determined that the use of physiological perfusion pressures leads to increased left ventricular (LV) pressures but results in a loss of function over time, making it ideal conditions for organ assessment. Conversely, lower-than-physiological perfusion pressures lead to decreased LV pressures but prevent loss of function over time, which is preferable when longer perfusion times are relevant to experimental needs. Similarly, the use of adenosine as a pharmacological intervention was found to decrease both edema formation and inflammatory responses. In contrast, the use of packed red blood cells as oxygen carriers appears to induce a pro-inflammatory response and cause greater cardiac damage, particularly when combined with low perfusion pressures.

Comparison between norepinephrine plus epinephrine and norepinephrine plus vasopressin after return of spontaneous circulation in patients with out-of-hospital cardiac arrest

There is insufficient evidence regarding the use of second-line vasopressors following norepinephrine administration in the post-resuscitation management of patients with out-of-hospital cardiac arrest (OHCA). Therefore, this study aimed to investigate the survival outcomes between norepinephrine plus epinephrine and norepinephrine plus vasopressin as vasopressor combinations after return of spontaneous circulation (ROSC) in patients with OHCA. This retrospective observational study included data from a prospective multicenter registry. Adult patients with OHCA who achieved sustained ROSC and received vasopressor combinations of norepinephrine plus epinephrine or norepinephrine plus vasopressin were included in the study. The variable of interest was the vasopressor combination either norepinephrine plus epinephrine or norepinephrine plus vasopressin within 24 h from sustained ROSC. The primary outcome was survival to discharge. Multivariable logistic regression analysis was conducted. Between October 2015 and June 2024, 901 patients were analyzed. Survival to discharge and good neurological outcome were significantly higher in the group with norepinephrine plus epinephrine than in the group with norepinephrine plus vasopressin (17.0% vs. 9.1%, p = 0.001, and 8.1% vs. 3.2%, p = 0.002, respectively). Norepinephrine plus vasopressin was independently associated with worse survival to discharge and neurological outcome compared to norepinephrine plus epinephrine, after adjusting for potential confounders (adjusted odds ratio [aOR] 0.454, 95% confidence interval [CI] 0.277-0.746, p = 0.002 and aOR 0.346, 95% CI 0.150-0.794, p = 0.012, respectively). These findings were maintained in multiple regression models and sensitivity analyses. Norepinephrine plus epinephrine administration within 24 h from sustained ROSC showed better survival to discharge than norepinephrine plus vasopressin in patients with OHCA.

Coronary Stent-Induced Kounis Syndrome: A Case Report

Kounis syndrome is an acute coronary syndrome triggered by allergic hypersensitivity to various stimuli. Here, we report the case of a 54-year-old man who had coronary stent-induced type III Kounis syndrome. The patient developed a rash on the anterior chest wall and experienced throat discomfort 40 minutes after stent implantation in the left anterior descending artery. Given his history of allergies, a presumptive diagnosis of anaphylaxis was made, and 0.5 mg of adrenaline was injected intramuscularly into the left thigh. The patient's symptoms initially resolved; however, approximately 50 minutes after the onset of the allergic reaction, he developed chest pain accompanied by ST-segment elevation in the anterior leads. Emergency coronary angiography revealed total occlusion at the mid-portion of the distal stent implanted in the left anterior descending artery, which was treated with repeated ballooning. The patient was later found to have a metal allergy. This case highlights the importance of obtaining a thorough allergy history, particularly regarding metal allergies, and recognizing Kounis syndrome as a potential cause of stent thrombosis associated with allergic hypersensitivity during coronary interventions.

From Escalate to Elevate: A New Paradigm for Comprehensive Cardiogenic Shock Management

Patients with cardiogenic shock (CS) present with critical hemodynamic compromise with low cardiac output (CO) resulting in end-organ dysfunction. Prognosis is closely related to the severity of shock, and treatment of patients with CS is resource intensive. In this review, we consider the current treatment paradigms alongside the evidence that underpins them. The current standard of treatment relies on a feedback mechanism, where small changes in treatment are assessed to see if clinical improvement occurs. This leads to delays that increase time in the shock state. The novel approach described proposes immediate treatment to ameliorate the shock state to "break" the shock spiral as quickly and decisively as possible, suggesting new metrics to measure performance.

Evaluation of a novel compliance-matching aortic graft in a swine model

The mismatch of elastic properties between the arterial tissue and the vascular grafts, commonly called compliance mismatch, is responsible for many deleterious post-operative complications. Currently, there is an absence of prostheses that conform with the compliance of healthy aortas. We aimed to evaluate the in vivo performance of novel compliance-matching grafts in a swine model and compare it to the native aorta and to gold-standard aortic grafts.We proposed a compliance-matching graft design, composed of a standard aortic graft surrounded by an optimized Nickel-Titanium compliance-augmenting layer. We replaced the thoracic aorta of six domestic pigs with compliance-matching grafts under cardiopulmonary bypass. We removed the compliance-regulating layer of the compliant grafts, so that gold-standard grafts remained implanted. The aortic pressure and flow rate were measured at the three stages of the experiment to assess hypertension and arterial stiffness. The compliance-matching grafts were implanted without inducing post-operative hypertension by maintaining systolic pressure (p = 0.26), aortic pulse wave velocity (p = 0.89) and aortic distensibility (p = 0.67) at healthy levels. The gold-standard grafts caused a significant rise in systolic pressure (p = 0.005), pulse wave velocity (p = 0.012) and they approximately doubled pulse pressure (p < 0.001). Our novel compliant grafts could diminish the complications caused by compliance-mismatch and they could surpass the clinical performance of existing prostheses. The proposed grafts comprise a step towards optimized treatment and improved life expectancy of patients subjected to aortic replacement.

Omecamtiv Mecarbil in Systolic Heart Failure: Clinical Efficacy and Future Directions of a Novel Myosin-Activating Inotropic Agent

Heart failure with reduced ejection fraction (HFrEF) remains a global health challenge, associated with high morbidity, mortality, and rising healthcare costs. Despite advances in guideline-directed therapy, many patients, especially those with severely reduced ejection fraction, remain symptomatic. Traditional inotropes, including β-agonists and phosphodiesterase inhibitors, are limited in chronic HFrEF due to risks of arrhythmias, calcium overload, and increased myocardial oxygen demand. Omecamtiv mecarbil (OM) is a novel cardiac myosin activator that enhances systolic contraction by increasing the efficiency of actin-myosin interactions. It prolongs systolic ejection time and improves stroke volume without elevating intracellular calcium or energy consumption. Although theoretical concerns exist regarding impaired diastolic filling, clinical trials have not confirmed such adverse effects in most patients. This narrative review discusses OM's pharmacologic profile, clinical trial data, and its potential as an adjunct therapy in advanced HFrEF. While not yet guideline-recommended, OM may benefit patients who remain symptomatic despite optimal treatment.

Effect of amphetamines on blood pressure

BACKGROUND

Daily ingestion of amphetamines is common, as they are widely prescribed for attention-deficit hyperactivity disorder (ADHD) and other diagnoses. People also use amphetamines recreationally or in an attempt to boost cognitive or athletic performance. Amphetamines have the potential to increase blood pressure, and we do not know if the long-term benefits of daily amphetamine use outweigh the potential harms.

OBJECTIVES

Primary: to quantify the changes in systolic and diastolic blood pressure in children and adults taking amphetamines, compared to placebo. Secondary: to quantify the changes in heart rate in children and adults taking amphetamines, compared to placebo; to quantify the number of withdrawals due to adverse effects of amphetamine, compared to placebo.

SEARCH METHODS

We used the Cochrane Hypertension Specialized Register, CENTRAL, MEDLINE, Embase and two clinical trial registers, together with reference checking and contact with study authors to identify the studies included in the review. We imposed no restrictions on language, publication year or publication status. The latest search date was March 2023.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that compared the effects of daily oral amphetamines versus placebo on blood pressure. There were no restrictions on participants' age or gender.

DATA COLLECTION AND ANALYSIS

We used standard methods expected by Cochrane. Primary outcomes were change in systolic and diastolic blood pressure (measured in millimeters of mercury (mmHg) above atmospheric pressure; continuous outcomes). Secondary outcomes were heart rate (measured as beats per minute; continuous outcome) and withdrawals due to adverse effects (dichotomous outcome). We calculated continuous outcomes as mean differences (MD) with 95% confidence intervals (CI). We expressed withdrawals due to adverse effects as a risk ratio with 95% CI. We used a fixed-effect model to pool effect sizes from all studies.

MAIN RESULTS

We included 56 RCTs with a total of 10,583 participants, both adults and children. Most studies were conducted in North America (mainly the USA), followed by Europe. A few studies took place in Asia (Japan) and Australia. The studies tested racemic amphetamine, dextroamphetamine, mixed amphetamine salts, lisdexamfetamine dimesylate, methyl​enedioxy​methamphetamine (MDMA) and methylphenidate. The amphetamines were prescribed for ADHD, weight loss and other indications. In 48 RCTs, blood pressure was measured within 24 hours of the last dose. Based on data from all included studies, amphetamines increased systolic blood pressure (SBP) by 1.93 mmHg (95% CI 1.54 to 2.31) and diastolic blood pressure (DBP) by 1.84 mmHg (95% CI 1.51 to 2.16) (56 studies, 10,583 participants; high-certainty evidence for both). Amphetamines increased heart rate by 3.71 beats per minute (95% CI 3.27 to 4.14; 47 studies, 10,075 participants; high-certainty evidence). In a subgroup analysis limited to studies that gave participants amphetamines for at least eight weeks, the effects were similar, suggesting that these are sustained effects. These findings suggest that people taking daily oral amphetamines are at increased risk of adverse cardiovascular events. Participants in the amphetamine group were also more likely to withdraw from the study due to adverse effects compared to those given placebo (risk ratio 2.69, 95% CI 2.13 to 3.40; absolute risk increase of 4.3% over an average duration of 1 month; 42 studies, 8952 participants; high-certainty evidence). In general, the studies were well-executed, and the methodology was sound. We judged most studies to have a low risk of bias across most domains. Selection bias (random sequence generation and allocation concealment) was the domain most often rated as at unclear risk of bias, because the methods used were not reported. We judged 13 studies (23%) to have a high risk of bias in at least one of the seven domains, primarily due to high dropout rates, leading to a high risk of attrition bias.

AUTHORS' CONCLUSIONS

Daily oral amphetamines increase blood pressure, heart rate, and withdrawals due to adverse effects, with these effects observed across all time points, including shorter (≤ four weeks) and longer durations (> four weeks to < eight weeks; ≥ eight weeks) of use. Future trials should measure blood pressure using 24-hour ambulatory monitoring and assess the effect of long-term use.

Dobutamine, Epinephrine, and Milrinone Accelerate Particle Transport Velocity in Murine Tracheal Epithelium via Ca2+ Release from Caffeine-Sensitive Internal Stores

Mucociliary clearance, the ability of the respiratory tract to protect the integrity of the airways through the mechanical removal of potentially harmful substances, is of enormous importance during intensive care treatment. The present study aimed to evaluate the influence of clinically relevant inotropic agents on mucociliary clearance. The particle transport velocity (PTV) of isolated murine tracheae was measured as a surrogate for mucociliary clearance in the presence of dobutamine, epinephrine, and milrinone. Inhibitory substances were applied to elucidate the signal transduction cascades and the value and origin of calcium ions which provoke alterations in mucociliary clearance function. Dobutamine, epinephrine, and milrinone increased the PTV in a dose-dependent manner with half maximal effective concentrations of 75.7 nM, 87.0 nM, and 13.7 µM, respectively. After the depletion of intracellular calcium stores, no increase in PTV was observed after administering any of the three inotropic agents. While dobutamine and epinephrine activated β-adrenergic receptors, epinephrine used both the phospholipase C (PLC) and protein kinase A (PKA) pathway to promote the release of intracellular Ca2+. However, dobutamine primarily acted on the PKA pathway, having only a minor influence on the PLC pathway. The induced changes in PTV following milrinone administration required both the PKA and PLC pathway, although the PKA pathway was responsible for most of the induced changes. In conclusion, the common inotropic agents dobutamine, epinephrine, and milrinone increase murine PTV in a concentration-dependent manner and ultimately release Ca2+ from intracellular calcium stores, suggesting the function of changes in mucociliary clearance in the respiratory tract.

Right Heart Failure in the Intensive Care Unit: Etiology, Pathogenesis, Diagnosis, and Treatment

Right heart (RH) failure carries a high rate of morbidity and mortality. Patients who present with RH failure often exhibit complex aberrant cardio-pulmonary physiology with varying presentations. The treatment of RH failure almost always requires care and management from an intensivist. Treatment options for RH failure patients continue to evolve rapidly with multiple options available, including different pharmacotherapies and mechanical circulatory support devices that target various components of the RH circulatory system. An understanding of the normal RH circulatory physiology, treatment, and support options for the RH failure patients is necessary for all intensivists to improve outcomes. The purpose of this review is to provide clinical guidance on the diagnosis and management of RH failure within the intensive care unit setting, and to highlight the different pathophysiological manifestations of RH failure, its hemodynamics, and treatment options available at the disposal of the intensivist.

Home Milrinone Therapy for Paediatric Advanced Heart Failure Patients: A Canadian Single-Centre Experience

Background

End-stage heart failure (ESHF) is the primary reason for heart transplantation in children with cardiomyopathy. Despite optimizing oral heart failure (HF) medications, some paediatric patients progress to ESHF, necessitating mechanical circulatory support and/or transplantation. Continuous milrinone intravenous support has been used to bridge paediatric patients to transplant. This study aimed to review and report the safety and outcomes of our home milrinone therapy (HMT) programme.

Methods

This single-centre, retrospective cohort study included paediatric patients discharged on HMT between 2001 and 2022. Data were collected from the SickKids HF Database. Outcomes of interest included frequency and indications for rehospitalization, catheter-related complications, and outcomes at the conclusion of therapy.

Results

Thirty-six patients were included, with a median age of 3.6 years and a median weight of 13.1 kg at HMT initiation. HMT was used as a bridge to transplantation (58%) recovery/candidacy (22%), palliative care (17%), and surgical repair (3%). The median duration on HMT was 88 days. Twenty-four patients (67%) were readmitted at least once with a total of 70 admissions, primarily due to central line-related issues (35%) and worsening HF (32%). Among patients discharged as a bridge to transplant, 52% were admitted from home for transplant, whereas 33% required readmission until transplant. No deaths were directly related to HMT.

Conclusions

HMT is a safe and effective method for supporting children with ESHF. This therapy allows children to return to their home environment.

Effects of noradrenaline and phenylephrine on cerebral oxygen saturation during cardiopulmonary bypass in cardiac surgery

Cardiopulmonary bypass (CPB) in cardiac surgery is associated with a high risk of postoperative neurological complications. Perioperative use of vasopressors is common to counteract arterial hypotension in this setting. However, use of α-agonist vasopressors has been associated with cerebral desaturations. Given that reductions in cerebral oxygen saturation (S c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ ) can increase postoperative neurological dysfunction, we aimed to investigate the impact of noradrenaline (NA) and phenylephrine (PE) onS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ during the CPB period of a cardiac surgery in 36 patients scheduled for an elective cardiac surgery. Patients were randomized to the intra-operative use of either NA or PE. During CPB, mean arterial pressure (MAP) was elevated pharmacologically to predefined thresholds of 60 and 80 mmHg, while CPB flow was kept constant. TheS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ values were recorded for 5 min per MAP threshold. The MAP increased adequately between thresholds of 60 and 80 mmHg (NA, 59 ± 3 vs. 81 ± 3 mmHg and PE, 61 ± 4 vs. 81 ± 3 mmHg; P ˂ 0.01). TheS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ decreased between pressure thresholds of 60 and 80 mmHg (NA, 70 ± 11 vs. 69 ± 11 mmHg and PE, 64 ± 11 vs. 63 ± 11 mmHg; P ˂ 0.01). Reduction inS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ did not differ between vasopressors. The mean relative decrease inS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ across groups was 2.0% (95% confidence interval: 0.6 to 2.1). Elevation in MAP mediated solely by vasopressors induces significant decreases inS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ during cardiac surgery under CPB. However, their impact onS c O 2 ${S_{{\mathrm{c}}{{\mathrm{O}}_2}}}$ remains clinically non-significant according to current guidelines.

Impact of epinephrine on neurological outcomes in out-of-hospital cardiac arrest after automated external defibrillator use in Japan

OHCA (out-of-hospital cardiac arrest) patients have improved neurological outcomes with public-access automated external defibrillator (PAD) use. However, the benefit of epinephrine administration after PAD use remains controversial. The purpose of the study was to investigate the impact of epinephrine administration on neurological outcomes in OHCA patients after PAD use. This study assessed 2,059,417 patients from the All-Japan Utstein Registry between 2005 and 2021. Patients were categorized into two groups: shockable and non-shockable rhythms on emergency medical service (EMS) arrival. Propensity score matching was used to adjust for various confounders and to analyze the impact of epinephrine administration on one-month favorable neurological outcomes. Criteria for bystander PAD was met by 11,629 (0.56%) of the enrolled patients. The mean age was 70 years with 71.9% male. Among them, 38.6% had shockable rhythms and 61.4% had non-shockable rhythms. After the matching, epinephrine administration negatively affected one-month favorable neurological outcome in patients with both shockable (14.7% vs. 41.1%, OR = 0.24, 95% CI = 0.19-0.31) and non-shockable rhythms (3.6% vs. 10.8%, OR = 0.31, 95% CI = 0.23-0.42). These findings suggest that epinephrine administration did not improve neurological outcomes in patients with OHCA after PAD use, providing insights to optimize EMS protocols for OHCA.

Mechanical Circulatory Support for Right Ventricular Primary Graft Dysfunction After Heart Transplant: A Review

Primary graft dysfunction (PGD) is the most common cause of early mortality following heart transplantation. Although PGD can affect both ventricles, isolated right ventricular dysfunction (RV-PGD) is observed in nearly half of PGD patients. RV-PGD requires specific medical management to support the preload, afterload, and function of the failing RV; however, the use of mechanical circulatory support of the RV (RV-MCS) might be required when optimal medical therapy is insufficient in preventing forward failure and retrograde venous congestion. While RV-MCS options provide the opportunity to prevent or to recover from circulatory shock states, MCS is associated with a significant risk of complications. As a result of recent developments in short-term mechanical support devices, less invasive, percutaneous options for RV-MCS are available. In this review, we discuss the available devices, their advantages and disadvantages, and reported outcomes in RV-PGD.

Drug-Induced Myocardial Infarction: A Review of Pharmacological Triggers and Pathophysiological Mechanisms

Myocardial infarction (MI) is a significant cardiovascular event caused by the decrease in or complete cessation of blood flow to a portion of the myocardium. It can arise from a variety of etiological factors, including pharmacological triggers. This review aims to explore the diverse drugs and substances that might lead to drug-induced myocardial infarction, focusing on their mechanisms of action and the pathophysiological processes involved. Various established and emerging pharmacological agents that could elevate the risk of myocardial infarction, such as nonsteroidal anti-inflammatory drugs, hormonal therapies, anticoagulants, and antipsychotic medications, are discussed. The role of drug-induced endothelial dysfunction, coronary artery spasm, and thrombosis are presented in order to highlight the underlying mechanisms. This review emphasizes the need for increased awareness among healthcare professionals to mitigate the risks associated with different pharmacological therapies to improve patient outcomes.

Identifying and mitigating risk of postcardiotomy cardiogenic shock in patients with ischemic and nonischemic cardiomyopathy

OBJECTIVES

To identify preoperative predictors of postcardiotomy cardiogenic shock in patients with ischemic and nonischemic cardiomyopathy and evaluate trajectory of postoperative ventricular function.

METHODS

From January 2017 to January 2020, 238 patients with ejection fraction <30% (206/238) or 30% to 34% with at least moderately severe mitral regurgitation (32/238) underwent conventional cardiac surgery at Cleveland Clinic, 125 with ischemic and 113 with nonischemic cardiomyopathy. Preoperative ejection fraction was 25 ± 4.5%. The primary outcome was postcardiotomy cardiogenic shock, defined as need for microaxial temporary left ventricular assist device, extracorporeal membrane oxygenation, or vasoactive-inotropic score >25. RandomForestSRC was used to identify its predictors.

RESULTS

Postcardiotomy cardiogenic shock occurred in 27% (65/238). Pulmonary artery pulsatility index <3.5 and pulmonary capillary wedge pressure >19 mm Hg were the most important factors predictive of postcardiotomy cardiogenic shock in ischemic cardiomyopathy. Cardiac index <2.2 L·min-1 m-2 and pulmonary capillary wedge pressure >21 mm Hg were the most important predictive factors in nonischemic cardiomyopathy. Operative mortality was 1.7%. Ejection fraction at 12 months after surgery increased to 39% (confidence interval, 35-40%) in the ischemic group and 37% (confidence interval, 35-38%) in the nonischemic cardiomyopathy group.

CONCLUSIONS

Predictors of postcardiotomy cardiogenic shock were different in ischemic and nonischemic cardiomyopathy. Right heart dysfunction, indicated by low pulmonary artery pulsatility index, was the most important predictor in ischemic cardiomyopathy, whereas greater degree of cardiac decompensation was the most important in nonischemic cardiomyopathy. Therefore, preoperative right heart catheterization will help identify patients with low ejection fraction who are at greater risk of postcardiotomy cardiogenic shock.

Low-dose dobutamine in acute myocardial infarction with intermediate to high risk of cardiogenic shock development (the DOBERMANN-D trial): study protocol for a double-blinded, placebo-controlled, single-center, randomized clinical trial

BACKGROUND

Cardiogenic shock (CS) occurs in 5-10% of patients with acute myocardial infarction (AMI), and the condition is associated with a 30-day mortality rate of up to 50%. Most of the AMI patients are in SCAI SHOCK stage B upon hospital arrival, but some of these patients will progression through the stages to overt shock (SCAI C-E). Around one third of patients who develop CS are not in shock at the time of hospital admission. Pro-B-type natriuretic peptide (proband) is a biomarker closely related to CS development. The aim of this study is to investigate the potential for preventing progression of hemodynamic instability by early inotropic support with low-dose dobutamine infusion administrated after revascularization in AMI patients with intermediate to high risk of in-hospital CS development.

METHODS

This investigator-initiated, double-blinded, placebo-controlled, randomized, single-center, clinical trial will include 100 AMI patients (≥ 18 years) without CS at hospital admission and at intermediate-high risk of in-hospital CS development (ORBI risk score ≥ 10). Patients will be randomized in a 1:1 ratio to a 24 h intravenous (IV) infusion of dobutamine (5 μg/kg/min) or placebo (NaCl) administrated after acute percutaneous coronary intervention (PCI) (< 24 h from symptom onset). Blood samples are drawn at time points from study inclusion (before infusion, 12, 24, 36, and 48 h). The primary outcome is peak plasma proBNP within 48 h after infusion as a surrogate-measure for the hemodynamic status. Hemodynamic function will be assessed pulse rate, blood pressure, and lactate within 48 h after infusion and by transthoracic echocardiography (TTE) performed after 24-48 h and at follow-up after 3 months. Markers of cardiac injury (troponin T and creatine kinase MB (CK-MB)) will be assessed.

DISCUSSION

Early inotropic support with low-dose dobutamine infusion in patients with AMI, treated with acute PCI, and at intermediate-high risk of in-hospital CS may serve as an intervention promoting hemodynamic stability and facilitating patient recovery. The effect will be assessed using proBNP as a surrogate marker of CS development, hemodynamic measurements, and TTE within the initial 48 h and repeated at a 3-month follow-up.

TRIAL REGISTRATION

The Regional Ethics Committee : H-21045751. EudraCT: 2021-002028-19.

CLINICALTRIALS

gov: NCT05350592, Registration date: 2022-03-08. WHO Universal Trial Number: U1111-1277-8523.

Is there a role for biogenic amine receptors in mediating β-phenylethylamine and RO5256390-induced vascular contraction?

BACKGROUND

Substantial evidence indicates trace amines can induce vasoconstriction independently of noradrenaline release. However, the mechanism underlying noradrenaline-independent vasoconstrictor responses to trace amines has not yet been established. This study evaluates the role of trace amine-associated receptor 1 (TAAR1) and other biogenic amine receptors in mediating β-phenylethylamine and the TAAR-1 selective agonist RO5256390-induced vasoconstriction.

METHODS

Vasoconstrictor responses to β-PEA and the TAAR1-selective agonist, RO5256390 were assessed in vitro in endothelium-denuded aortic rings and third-order mesenteric arteries of male Sprague Dawley rats.

RESULTS

β-PEA and RO5256390 induced concentration-dependent vasoconstriction of aortic rings but not third-order mesenteric arteries. Vasoconstrictor responses in aortic rings were insensitive to antagonists of 5-HT. The murine-selective TAAR1 antagonist, EPPTB, had no effect on either β-PEA or RO5256390-induced vasoconstriction. The α1-adrenoceptor antagonist, prazosin, and the α2-adrenoceptor antagonist, yohimbine, induced a shift of the β-PEA concentration response curve too small to be ascribed to antagonism of α1-or α2-adrenoceptors, respectively. The α2-adrenoceptor antagonist atipamezole had no effect on β-PEA or RO5256390-induced vasoconstriction.

CONCLUSION

Vasoconstrictor responses to trace amines are not mediated by classical biogenic amine neurotransmitter receptors. Insensitivity of β-PEA vasoconstrictor responses to EPPTB, may be explained by its low affinity for rat rather than murine TAAR1. Therefore, TAAR1 remains the most likely candidate receptor mediating vasoconstrictor responses to trace amines and that prazosin and yohimbine have low affinity for TAAR1.

Silent Threats of the Heart: A Case Series and Narrative Review on Suicide Left Ventricle Post-Aortic Valve Replacement in Patients with Dynamic LVOT Obstruction and Aortic Stenosis

Aortic stenosis (AS) is the most prevalent valvular heart disease in Europe and North America, with transcatheter aortic valve implantation (TAVI) revolutionizing its management. Hypertrophic left ventricle (HLV) frequently coexists with AS, complicating treatment due to the associated risk of left ventricular outflow tract (LVOT) obstruction, heart failure, and sudden death. A rare but severe post-aortic valve replacement (AVR) complication, termed "suicide left ventricle" (SLV), has emerged, necessitating further study. This report synthesizes current literature on SLV, its pathophysiology, and management strategies, alongside four patient case studies. The patients aged 79-87 years, underwent AVR for symptomatic AS with HLV. Post-AVR, all experienced severe complications, including dynamicLVOT gradients, systolic anterior motion (SAM) of the mitral valve, and severe hypotension, leading to death in two cases. One patient survived following surgical aortic valve replacement (SAVR) with surgical myectomy. One patient survived after TAVI. These cases highlight the critical importance of multidisciplinary Heart Team evaluations and personalized treatment plans in managing SLV. Despite advancements in AVR, SLV remains a complex, life-threatening condition, requiring an exhaustive and multifaceted approach for optimal patient outcomes. This report offers valuable insights into SLV occurrence and management from a clinical perspective.

Landiolol for refractory ventricular fibrillation in out-of-hospital cardiac arrest: A randomized, double-blind, placebo-controlled, pilot trial

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) complicated by refractory ventricular fibrillation (VF) is associated with poor outcome. Beta-1-receptor selective blockade might overcome refractory VF and improve survival. This trial investigates the efficacy and safety of prehospital landiolol in OHCA and refractory VF.

METHODS

In this randomized, double-blind, placebo-controlled pilot trial, patients with OHCA and recurrent or refractory VF (at least 3 defibrillation attempts and last rhythm shockable), pretreated with epinephrine and amiodarone, were allocated to receive add-on treatment with landiolol or placebo. Landiolol was given as a 20 mg bolus infusion. The primary efficacy outcome was time from trial drug infusion to sustained return of spontaneous circulation (ROSC). Safety outcomes included the onset of bradycardia and asystole.

RESULTS

A total of 36 patients were enrolled, 19 were allocated to the landiolol group and 17 to the placebo group. Time from trial drug infusion to sustained ROSC was similar between treatment groups (39 min [landiolol] versus 41 min [placebo]). Sustained ROSC was numerically lower in the landiolol group compared with the placebo group (7 patients [36.8%] versus 11 patients [64.7%], respectively). Asystole within 15 min of trial drug infusion occurred significantly more often in the landiolol group than in the placebo group (7 patients [36.8%] and 0 patients [0.0%], respectively).

CONCLUSION

In patients with OHCA and refractory VF who are pretreated with epinephrine and amiodarone, add-on bolus infusion of landiolol 20 mg did not lead to a shorter time to sustained ROSC compared with placebo. Landiolol might be associated with bradycardia and asystole.

Cardiac Myosin Activator Omecamtiv Mecarbil: Novel Treatment for Systolic Heart Failure

Systolic Heart failure is a complex clinical syndrome characterized by a decrease in cardiac contractility and a reduction in organ perfusion. Current pharmacologic inotropes attempt to improve contractility via indirect mechanisms but are limited in terms of safety and effectiveness. Omecamtiv mecarbil is a novel agent in a new class of drugs known as cardiac myosin activators; their unique mechanism of action involves directly activating the enzymatic pathway in the cardiac myocyte as a way to improve ventricular contraction. Preclinical and clinical trials have found that omecamtiv mecarbil improves cardiac contractility without increasing the risk of any of the harmful effects that are associated with the currently available inotropic agents. Omecamtiv mecarbil is a worthwhile advance and patients with systolic heart failure would benefit from pharmacological use of this drug.

Outcomes of Vasopressin-Receptor Agonists Versus Norepinephrine in Adults With Perioperative Hypotension: A Systematic Review

Consensus statements recommend the use of norepinephrine and/or vasopressin for hypotension in cardiac surgery. However, there is a paucity of data among other surgical subgroups and vasopressin analogs. Therefore, the authors conducted a systematic review of randomized controlled trials (RCTs) to compare vasopressin-receptor agonists with norepinephrine for hypotension among those undergoing surgery with general anesthesia. This review was registered prospectively (CRD42022316328). Literature searches were conducted by a medical librarian to November 28, 2023, across MEDLINE, EMBASE, CENTRAL, and Web of Science. The authors included RCTs enrolling adults (≥18 years of age) undergoing any surgery under general anesthesia who developed perioperative hypotension and comparing vasopressin receptor agonists with norepinephrine. The risk of bias was assessed by the Cochrane risk of bias tool for randomized trials (RoB-2). Thirteen (N = 719) RCTs were included, of which 8 (n = 585) enrolled patients undergoing cardiac surgery. Five trials compared norepinephrine with vasopressin, 4 trials with terlipressin, 1 trial with ornipressin, and the other 3 trials used vasopressin as adjuvant therapy. There was no significant difference in all-cause mortality. Among patients with vasoplegic shock after cardiac surgery, vasopressin was associated with significantly lower intensive care unit (N = 385; 2 trials; mean 100.8 v 175.2 hours, p < 0.005; median 120 [IQR 96-168] v 144 [96-216] hours, p = 0.007) and hospital lengths of stay, as well as fewer cases of acute kidney injury and atrial fibrillation compared with norepinephrine. One trial also found that terlipressin was associated with a significantly lower incidence of acute kidney injury versus norepinephrine overall. Vasopressin and norepinephrine restored mean arterial blood pressure with no significant differences; however, the use of vasopressin with norepinephrine was associated with significantly higher mean arterial blood pressure versus norepinephrine alone. Further high-quality trials are needed to determine pooled treatment effects, especially among noncardiac surgical patients and those treated with vasopressin analogs.

The cerebral and cardiac effects of Norepinephrine in an experimental cardiac arrest model

Introduction

Epinephrine has been the main drug recommended for decades during cardiopulmonary resuscitation (CPR). But epinephrine's ß-adrenergic effects might increase myocardial oxygen consumption and may cause arrythmias after ROSC. Norepinephrine has a weaker ß-adrenergic effect and could be useful during CPR. Studies on norepinephrine's effect on hemodynamic parameters and cerebral perfusion are scarce. This study aimed to assess norepinephrine's hemodynamic impact in an experimental model of cardiac arrest.

Methods

After an initial dose study to determine the optimal dose, we conducted a prospective randomized study with 19 pigs. After 3 minutes of untreated ventricular fibrillation, animals received boluses of 0.5 mg Epinephrine (EPI) or 1 mg Norepinephrine (NE) every 5 minutes during CPR. Coronary perfusion pressure (CPP), carotid blood flow (CBF) and cerebral perfusion pressure (CePP) were evaluated.

Results

At baseline, hemodynamic parameters did not differ between the two groups. During CPR, CPP and CBF were similar: 17.3 (12.8; 31.8) in the EPI group vs 16.0 (11.1; 37.7) in the NE group, p = 0.9 and 28.4 (22.0; 54.8) vs 30.8 (12.2; 56.3) respectively, p = 0.9. CePP was not significantly lower during resuscitation in the NE group compared to the EPI group: 12.2 (-8.2; 42.2) vs 7.8 (-2.0; 32.0) p = 0.4. Survival rate was low with only one animal in the EPI group and 2 in the NE group.

Conclusion

Cerebral perfusion pressure, coronary perfusion pressure and carotid blood flow during CPR did not significantly differ between the norepinephrine group and the epinephrine group. Further investigations should evaluate different options such as a continuous NE infusion.

Comparison of intraocular pressure profiles during the water drinking test and the modified diurnal tension curve

OBJECTIVES

To compare intraocular pressure (IOP) during the water drinking test (WDT) and modified diurnal tension curve (mDTC) in open-angle glaucoma (OAG) patients, using multimodal, observer-masked tonometry.

METHODS

Open-angle glaucoma subjects were prospectively enroled, excluding those who had undergone glaucoma filtration or laser surgery. Two-hourly mDTC Goldmann applanation (GAT) and rebound tonometry (RT) was performed between 8:00 and 16:00, and every 15 min for 45 min after ingestion of 800mls of water. Blood pressure, heart rate, pupillometry measurements, and optical coherence tomography (AS-OCT) were also recorded.

RESULTS

Forty-two subjects' right eyes were included. 48% were using topical glaucoma medication. Mean baseline IOP was 14.9 ± 4.52 mmHg, with mean visual field mean deviation (±SD) -5.05 ± 5.45 dB. Strong association was found between maximum IOP during mDTC and WDT (r = 0.90, 95% CI 0.82-0.95 p < 0.0001) with agreement (mDTC-WDT) bias -0.82 mmHg, 95% LoA -1.46 to -0.18. During the WDT, mean systolic blood pressure (±SD) increased from 140.0 ± 20.0 to 153.3 ± 24.0 mmHg (p < 0.0001), mean heart rate ( ± SD) reduced from 69.5 ± 11.3 bpm to 63.6 ± 10.0 bpm (p < 0.0001), and temporal iridocorneal angle increased from 29.2 ± 6.0° to 29.6 ± 5.2° (p = 0.04).

CONCLUSION

This study presents repeated, observer-masked IOP data showing strong correlation between maximum IOP during mDTC and WDT using multimodal tonometry. This supports WDT as a meaningful alternative to mDTC when investigating diurnal IOP characteristics in clinic, with reduced time requirements and associated costs.

Does Single Dose Epinephrine Improve Outcomes for Patients with Out-of-Hospital Cardiac Arrest and Bystander CPR or a Shockable Rhythm?

BACKGROUND

A single dose epinephrine protocol (SDEP) for out-of-hospital cardiac arrest (OHCA) achieves similar survival to hospital discharge (SHD) rates as a multidose epinephrine protocol (MDEP). However, it is unknown if a SDEP improves SHD rates among patients with a shockable rhythm or those receiving bystander cardiopulmonary resuscitation (CPR).

METHODS

This pre-post study, spanning 11/01/2016-10/29/2019 at 5 North Carolina EMS systems, compared pre-implementation MDEP and post-implementation SDEP in patients ≥18 years old with non-traumatic OHCA. Data on initial rhythm type, performance of bystander CPR, and the primary outcome of SHD were sourced from the Cardiac Arrest Registry to Enhance Survival. We compared SDEP vs MDEP performance in each rhythm (shockable and non-shockable) and CPR (bystander CPR or no bystander CPR) subgroup using Generalized Estimating Equations to account for clustering among EMS systems and to adjust for age, sex, race, witnessed arrest, arrest location, AED availability, EMS response interval, and presence of a shockable rhythm or receiving bystander CPR. The interaction of SDEP implementation with rhythm type and bystander CPR was evaluated.

RESULTS

Of 1690 patients accrued (899 MDEP, 791 SDEP), 19.2% (324/1690) had shockable rhythms and 38.9% (658/1690) received bystander CPR. After adjusting for confounders, SHD was increased after SDEP implementation among patients with bystander CPR (aOR 1.61, 95%CI 1.03-2.53). However, SHD was similar in the SDEP cohort vs MDEP cohort among patients without bystander CPR (aOR 0.81, 95%CI 0.60-1.09), with a shockable rhythm (aOR 0.96, 95%CI 0.48-1.91), and with a non-shockable rhythm (aOR 1.26, 95%CI 0.89-1.77). In the adjusted model, the interaction between SDEP implementation and bystander CPR was significant for SHD (p = 0.002).

CONCLUSION

Adjusting for confounders, the SDEP increased SHD in patients who received bystander CPR and there was a significant interaction between SDEP and bystander CPR. Single dose epinephrine protocol and MDEP had similar SHD rates regardless of rhythm type.

Dopamine infusion at typical infusion rates does not cause interference on plasma creatinine assays

a Objectives

Dopamine is known to cause negative interference on enzymatic creatinine measurement. However, its effect on the Jaffe reaction, and its concentration required to interfere with enzymatic reactions, remain uncertain. This study was designed to study the interference of stable dopamine infusion on Jaffe and enzymatic creatinine assays, as well as the effect of dopamine infusion drip arm contamination on both creatinine assays.

b Design and Methods

For the first part of the study, dopamine was spiked into pooled plasma samples at different concentrations to mimic the scenario of patients on dopamine infusion at an infusion rate between 2 and 20 μg/kg/min. For the second part, dopamine preparation of 2 g/L (same as the preparation used clinically) was mixed with pooled plasma samples at different proportions to mimic drip arm contamination. Creatinine concentrations were measured using Jaffe and enzymatic reactions.

c Results

The first part showed that creatinine measurements were not interfered by dopamine infusion at an infusion rate between 2 and 20 μg/kg/min. The second part showed that dopamine could negatively interfere with enzymatic creatinine assays, even with minute drip arm contamination. The effect on the Jaffe reaction was less significant.

d Discussion

Creatinine concentration could be reliably measured by Jaffe or enzymatic reactions if samples are from venous access sites other than the site of dopamine infusion. When dopamine interference on enzymatic creatinine assays is suspected, using the Jaffe reaction to cross-check may provide additional useful information.

Complexities of Infective Endocarditis in a Young Patient With Hypertrophic Obstructive Cardiomyopathy: A Case of Dual Valve Involvement and Neurological Complications

Infective endocarditis (IE) is a life-threatening infection predominantly affecting the endocardium and heart valves, commonly seen in older patients and those with pre-existing cardiac conditions. Although rare in younger individuals with intact cardiac valves, certain structural heart diseases such as hypertrophic obstructive cardiomyopathy (HOCM) can increase the risk. We present a unique case of a 39-year-old female with a known history of HOCM, a condition characterized by abnormally thickened cardiac muscle primarily affecting the left ventricle. This patient was diagnosed with group B streptococcus infective endocarditis. Notably, this case was complicated by septic emboli to the brain. This case underscores the significant risk of IE in patients with HOCM, a demographic usually less susceptible to IE. It underscores the importance of early recognition and aggressive management of IE, especially in patients with structural heart diseases.

Cardiac arrest, stony heart, and cardiopulmonary resuscitation: An updated revisit

The post-resuscitation period is recognized as the main predictor of cardiopulmonary resuscitation (CPR) outcomes. The first description of post-resuscitation syndrome and stony heart was published over 50 years ago. Major manifestations may include but are not limited to, persistent precipitating pathology, systemic ischemia/reperfusion response, post-cardiac arrest brain injury, and finally, post-cardiac arrest myocardial dysfunction (PAMD) after successful resuscitation. Why do some patients initially survive successful resuscitation, and others do not? Also, why does the myocardium response vary after resuscitation? These questions have kept scientists busy for several decades since the first successful resuscitation was described. By modifying the conventional modalities of resuscitation together with new promising agents, rescuers will be able to salvage the jeopardized post-resuscitation myocardium and prevent its progression to a dismal, stony heart. Community awareness and staff education are crucial for shortening the resuscitation time and improving short- and long-term outcomes. Awareness of these components before and early after the restoration of circulation will enhance the resuscitation outcomes. This review extensively addresses the underlying pathophysiology, management, and outcomes of post-resuscitation syndrome. The pattern, management, and outcome of PAMD and post-cardiac arrest shock are different based on many factors, including in-hospital cardiac arrest vs out-of-hospital cardiac arrest (OHCA), witnessed vs unwitnessed cardiac arrest, the underlying cause of arrest, the duration, and protocol used for CPR. Although restoring spontaneous circulation is a vital sign, it should not be the end of the game or lone primary outcome; it calls for better understanding and aggressive multi-disciplinary interventions and care. The development of stony heart post-CPR and OHCA remain the main challenges in emergency and critical care medicine.

Perioperative and Anesthetic Considerations in Shone's Complex

Shone's complex is a congenital cardiac disease consisting of the following four lesions: parachute mitral valve, supravalvar mitral ring, subaortic stenosis, and aortic coarctation. Though not all components are required for a diagnosis, the end result is both left ventricular inflow and outflow obstruction, which typically present in patients as congestive heart failure. The complex pathology requires careful management and surgical decision-making to ensure an optimal outcome. This review will focus on the anatomy, physiology, and perioperative anesthetic management of patients with Shone's complex.

Risk of arrhythmia in post-resuscitative shock after out-of-hospital cardiac arrest with epinephrine versus norepinephrine

OBJECTIVE

To determine the rates of clinically significant tachyarrhythmias and mortality in the management of post-resuscitative shock after return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest (OHCA) who receive a continuous epinephrine versus norepinephrine infusion.

DESIGN

Retrospective cohort study.

SETTING

A large multi-site health system with hospitals across the United States.

PATIENTS

Adult patients admitted for OHCA with post-resuscitative shock managed with either epinephrine or norepinephrine infusions within 6 h of ROSC.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Between May 5th, 2018, to January 31st, 2022, there were 221 patients admitted for OHCA who received post-resuscitative epinephrine or norepinephrine infusions. There was no difference in the rate of tachyarrhythmias between epinephrine and norepinephrine infusion in univariate (47.1% vs 41.7%, OR 1.24, 95% CI 0.71-2.20) or multivariable analysis (OR 1.34, 95% CI 0.68-2.62). Patients treated with epinephrine were more likely to die during hospitalization than those treated with norepinephrine (90.0% vs 54.3%, OR 6.21, 95% CI 2.37-16.25, p < 0.001). Epinephrine treated patients were more likely to have re-arrest during hospital admission (55.7% vs 14.6%, OR 5.77, 95% CI 2.74-12.18, p < 0.001).

CONCLUSION

There was no statistically significant difference in clinically significant cardiac tachyarrhythmias in post-OHCA patients treated with epinephrine versus norepinephrine infusions after ROSC. Re-arrest rates and in-hospital mortality were higher in patients who received epinephrine infusions in the first 6 h post-ROSC. Results of this study add to the literature suggesting norepinephrine may be the vasopressor of choice in post-OHCA patients with post-resuscitative shock after ROSC.

Medical therapy of cardiogenic shock: Contemporary use of inotropes and vasopressors

Cardiogenic shock is a primary cardiac disorder that results in both clinical and biochemical evidence of tissue hypoperfusion and can lead to multi-organ failure and death depending on its severity. Inadequate cardiac contractility or cardiac power secondary to acute myocardial infarction remains the most frequent cause of cardiogenic shock, although its contribution has declined over the past two decades, compared with other causes. Despite some advances in cardiogenic shock management, this clinical syndrome is still burdened by an extremely high mortality. Its management is based on immediate stabilization of haemodynamic parameters so that further treatment, including mechanical circulatory support and transfer to specialized tertiary care centres, can be accomplished. With these aims, medical therapy, consisting mainly of inotropic drugs and vasopressors, still has a major role. The purpose of this article is to review current evidence on the use of these medications in patients with cardiogenic shock and discuss specific clinical settings with indications to their use.

Takotsubo Syndrome and Coronary Artery Disease: Which Came First-The Chicken or the Egg?

Takotsubo syndrome (TTS) is a clinical condition characterized by temporary regional wall motion anomalies and dysfunction that extend beyond a single epicardial vascular distribution. Various pathophysiological mechanisms, including inflammation, microvascular dysfunction, direct catecholamine toxicity, metabolic changes, sympathetic overdrive-mediated multi-vessel epicardial spasms, and transitory ischemia may cause the observed reversible myocardial stunning. Despite the fact that TTS usually has an acute coronary syndrome-like pattern of presentation, the absence of culprit atherosclerotic coronary artery disease is often reported at coronary angiography. However, the idea that coronary artery disease (CAD) and TTS conditions are mutually exclusive has been cast into doubt by numerous recent studies suggesting that CAD may coexist in many TTS patients, with significant clinical and prognostic repercussions. Whether the relationship between CAD and TTS is a mere coincidence or a bidirectional cause-and-effect is still up for debate, and misdiagnosis of the two disorders could lead to improper patient treatment with unfavourable outcomes. Therefore, this review seeks to provide a profound understanding of the relationship between CAD and TTS by analyzing potential common underlying pathways, addressing challenges in differential diagnosis, and discussing medical and procedural techniques to treat these conditions appropriately.

The Impact of Inotropes and Vasopressors on Cerebral Oxygenation in Patients with Traumatic Brain Injury and Subarachnoid Hemorrhage: A Narrative Review

Traumatic brain injury (TBI) and subarachnoid hemorrhage (SAH) are critical neurological conditions that necessitate specialized care in the Intensive Care Unit (ICU). Managing cerebral perfusion pressure (CPP) and mean arterial pressure (MAP) is of primary importance in these patients. To maintain targeted MAP and CPP, vasopressors and/or inotropes are commonly used. However, their effects on cerebral oxygenation are not fully understood. The aim of this review is to provide an up-to date review regarding the current uses and pathophysiological issues related to the use of vasopressors and inotropes in TBI and SAH patients. According to our findings, despite achieving similar hemodynamic parameters and CPP, the effects of various vasopressors and inotropes on cerebral oxygenation, local CBF and metabolism are heterogeneous. Therefore, a more accurate understanding of the cerebral activity of these medications is crucial for optimizing patient management in the ICU setting.

Does Early Vasopressin in Septic Shock Improve Outcomes? An Important Piece to This Emerging Puzzle Has Arrived

In this month's Annals of Pharmacotherapy, the largest observational study assessing the early versus later use of vasopressin has been published. When this new study is combined with the other available observational studies, there are 2 important outcomes to focus on. When all the observational studies are pooled together, no reduction in new onset arrhythmias is seen (odds ratio [OR] = 0.91, 95% confidence interval [CI] = 0.41-1.95) with early versus late vasopressin use while the reduction in renal replacement therapy just missed statistical significance (OR = 0.56, 95% CI = 0.32-1.00). Early vasopressin likely does not reduce new onset arrhythmias versus later use but might reduce the need for renal replacement therapy.

Donor noradrenaline use is associated with better allograft survival in recipients of pancreas transplantation

INTRODUCTION

Outcomes following pancreas transplantation are suboptimal and better donor selection is required to improve this. Vasoactive drugs (VaD) are commonly used to correct the abnormal haemodynamics of organ donors in intensive care units. VaDs can differentially affect insulin secretion positively (dobutamine) or negatively (noradrenaline). The hypothesis was that some VaDs might induce beta-cell stress or rest and therefore impact pancreas transplant outcomes. The aim of the study was to assess relationships between VaD use and pancreas transplant graft survival.

METHODS

Data from the UK Transplant Registry on all pancreas transplants performed between 2004 and 2016 with complete follow-up data were included. Univariable- and multivariable-adjusted Cox regression analyses determined risks of graft failure associated with VaD use.

RESULTS

In 2,183 pancreas transplants, VaDs were used in the following numbers of donors: dobutamine 76 (3.5%), dopamine 84 (3.8%), adrenaline 161 (7.4%), noradrenaline 1,589 (72.8%) and vasopressin 1,219 (55.8%). In multivariable models, adjusted for covariates and the co-administration of other VaDs, noradrenaline use (vs non-use) was a strong predictor of better graft survival (hazard ratio [95% confidence interval] 0.77 [0.64-0.94], p = 0.01).

CONCLUSIONS

Noradrenaline use was associated with better graft survival in models adjusted for donor and recipient variables - this may be related to inhibition of pancreatic insulin secretion initiating pancreatic beta-cell 'rest'. Further research is required to replicate these findings and establish whether relationships are causal. Identification of alternative methods of inducing beta-cell rest could be valuable in improving graft outcomes.

What Factors Are Associated With Arterial Line-Related Limb Ischemia in Patients on Extracorporeal Membrane Oxygenation? A Single-Center Retrospective Cohort Study

OBJECTIVES

The primary purpose of this study was to identify factors associated with the development of arterial line-related limb ischemia in patients on extracorporeal membrane oxygenation (ECMO). The authors also sought to characterize and report the outcomes of patients who developed arterial line-related limb ischemia.

DESIGN

Retrospective cohort study.

SETTING

A single academic tertiary referral ECMO center.

PARTICIPANTS

Consecutive patients who were treated with ECMO over 6 years.

INTERVENTIONS

Use of arterial line.

MEASUREMENTS AND MAIN RESULTS

A total of 278 consecutive ECMO patients were included, with 19 (7%) patients developing arterial line-related limb ischemia during the ECMO run. Postcannulation Sequential Organ Failure Assessment (SOFA) (adjusted odds ratio [aOR] 1.20, 95% CI 1.08-1.32), Acute Physiology and Chronic Health Evaluation-II (aOR 0.84, 95% CI 0.74-0.95), and adjusted Vasopressor Dose Equivalence (aOR 1.03, 95% CI 1.01-1.05) scores were independently associated with the development of arterial line-associated limb ischemia. A SOFA score of ≥17 at the time of ECMO cannulation had an 80% sensitivity and 87% specificity for predicting arterial line-related limb ischemia.

CONCLUSIONS

Arterial line-related limb ischemia is much more common in ECMO patients than in the typical intensive care unit setting. The SOFA score may be useful in identifying which patients may be at risk for arterial line-related limb ischemia. As this was a single-center retrospective study, these results are inherently exploratory, and prospective multicenter studies are necessary to validate these results.

Perioperative and Anesthetic Considerations in Pediatric Valvar and Subvalvar Aortic Stenosis

Aortic stenosis (AS) is a common form of left ventricular outflow tract obstruction (LVOTO) in children with congenital heart disease. This review specifically considers the perioperative features of valvar (VAS) and subvalvar AS (subAS) in the pediatric patient. Although VAS and subAS share some clinical features and diagnostic approaches, they are distinct clinical entities with separate therapeutic options, which range from transcatheter intervention to surgical repair. We detail the pathophysiology of AS and highlight the range of treatment strategies with a focus on anesthetic considerations for the care of these patients before, during, and after intervention.

Managing the deteriorating child with suspected group A Streptococcus infection

Group A Streptococcus bacteria can cause various pyogenic infections such as tonsillitis, pharyngitis, scarlet fever, impetigo, erysipelas, cellulitis and pneumonia. Most group A Streptococcus infections in children are mild and respond positively to treatment with antibiotics. However, some children develop severe infection accompanied by complications such as sepsis and will require urgent treatment, which may include non-invasive or invasive ventilation and the administration of fluids and vasoactive agents. In some instances, for example if there are no beds available in the paediatric intensive care unit, these interventions may be undertaken in a ward setting. This article gives an overview of group A Streptococcus infection, including two rare but severe complications, streptococcal toxic shock syndrome and necrotising fasciitis. It uses a fictionalised case study to examine the management of the deteriorating child with suspected group A Streptococcus infection, including respiratory support, haemodynamic support and symptom management.

Association of Hypoalbuminemia With Clinical Outcomes in Patients Admitted With Acute Heart Failure

Albumin is a protein produced by the liver essential for maintaining blood volume and regulating fluid balance. Hypoalbuminemia is characterized by low levels of albumin in the blood. It is also a marker of malnutrition-inflammatory syndrome. Several studies have demonstrated its prognostic role in patients with chronic heart failure; however, data regarding hypoalbuminemia in acute heart failure admissions are scarce. This study aims to analyze the relationship between hypoalbuminemia and heart failure. We used a retrospective cohort study surveying data from the 2016-2018 combined National Inpatient Sample (NIS) database. Adult hospitalizations for heart failure patients were identified using the ICD-10 codes, stratified into cohorts with and without hypoalbuminemia. Primary outcomes were (1) in-patient mortality, (2) length of stay, and total hospital charge. We also reclassified the HF admissions with hypoalbuminemia to those with systolic or diastolic heart failure to compare any differences in mortality and other in-patient complications. Multivariate linear and logistic regression were used to adjust for confounders and to analyze the outcomes. There were 1,365,529 adult hospitalizations for Congestive Heart Failure (CHF), and among them 1,205,990 (88 %) had secondary diagnoses of hypoalbuminemia. Patients with comorbid hypoalbuminemia were, on average, 8 years older (P < 0.001), predominantly white race, and males (P-value <0.001). HF hospitalizations with hypoalbuminemia had double in-hospital mortality than those without (4.8% vs 2.7%, P < 0.001). However, there was no difference in mortality between patients with Systolic heart failure and Diastolic heart failure with concomitant low albumin levels (from 4.9 % vs 4.7%, P 0.13). We found that patients admitted with HF and concomitant Hypoalbuminemia (HA) had nearly twice the odds of in-patient mortality than those with normal albumin levels. The Length of Stay (LOS) was higher between comparison groups. THC remained statistically indifferent in patients regardless of albumin levels but was greater in hypoalbuminemic patients with Systolic heart failure than Diastolic heart failure ones.

Risk of arrhythmias following COVID-19: nationwide self-controlled case series and matched cohort study

AIMS

COVID-19 increases the risk of cardiovascular disease, especially thrombotic complications. There is less knowledge on the risk of arrhythmias after COVID-19. In this study, we aimed to quantify the risk of arrhythmias following COVID-19.

METHODS AND RESULTS

This study was based on national register data on all individuals in Sweden who tested positive for SARS-CoV-2 between 1 February 2020 and 25 May 2021. The outcome was incident cardiac arrhythmias, defined as international classification of diseases (10th revision) codes in the registers as follows: atrial arrhythmias; paroxysmal supraventricular tachycardias; bradyarrhythmias; and ventricular arrhythmias. A self-controlled case series study and a matched cohort study, using conditional Poisson regression, were performed to determine the incidence rate ratio and risk ratio, respectively, for an arrhythmia event following COVID-19.A total of 1 057 174 exposed (COVID-19) individuals were included in the study as well as 4 074 844 matched unexposed individuals. The incidence rate ratio of atrial tachycardias, paroxysmal supraventricular tachycardias, and bradyarrhythmias was significantly increased up to 60, 180, and 14 days after COVID-19, respectively. In the matched cohort study, the risk ratio during Days 1-30 following COVID-19/index date was 12.28 (10.79-13.96), 5.26 (3.74-7.42), and 3.36 (2.42-4.68), respectively, for the three outcomes. The risks were generally higher in older individuals, in unvaccinated individuals, and in individuals with more severe COVID-19. The risk of ventricular arrhythmias was not increased.

CONCLUSION

There is an increased risk of cardiac arrhythmias following COVID-19, and particularly increased in elderly vulnerable individuals, as well as in individuals with severe COVID-19.

Safety and Performance of the Aortix Device in Acute Decompensated Heart Failure and Cardiorenal Syndrome

BACKGROUND

Cardiorenal syndrome (CRS) complicates 33% of acute decompensated heart failure (ADHF) admissions, and patients with persistent congestion at discharge have high 30-day event rates.

OBJECTIVES

The purpose of this study was to evaluate a novel catheter-deployed intra-aortic entrainment pump (IAEP) in patients with ADHF with CRS and persistent congestion.

METHODS

A multicenter (n = 14), nonrandomized, single-arm, safety and feasibility study of IAEP therapy was conducted. Within patient changes (post-pre IAEP therapy) in fluid loss, hemodynamics, patient-reported dyspnea, and serum biomarkers were assessed using Wilcoxon signed-rank testing.

RESULTS

Of 21 enrolled patients, 18 received Aortix therapy. Mean ± SD patient age was 60.3 ± 7.9 years. The median left ventricular ejection fraction was 22.5% (25th-75th percentile: 10.0%-53.5%); 27.8% had a left ventricular ejection fraction ≥50%. Pre-therapy, patients received 8.7 ± 4.1 days of loop diuretic agents and 44% were on inotropes. Pump therapy averaged 4.6 ± 1.6 days, yielding net fluid losses of 10.7 ± 6.5 L (P < 0.001) and significant (P < 0.01) reductions in central venous pressure (change from baseline: -8.5 mm Hg [25th-75th percentile: -3.5 to -10.0 mm Hg]), pulmonary capillary wedge pressure (-11.0 mm Hg [25th-75th percentile: -5.0 to -14.0 mm Hg]), and serum creatinine (-0.2 mg/dL [25th-75th percentile: -0.1 to -0.5 mg/dL]) with improved estimated glomerular filtration rate (+5.0 mL/min/1.73 m2 [25th-75th percentile: 2.0-9.0 mL/min/1.73 m2]) and patient-reported dyspnea score (+16 [25th-75th percentile: 3-37]). Dyspnea scores, natriuretic peptides, and renal function improvements persisted through 30 days.

CONCLUSIONS

This pilot study of patients with ADHF, persistent congestion, and worsening renal function due to CRS supports the potential for safely achieving decongestion using IAEP therapy. These initial promising results provide the basis for future randomized clinical trials of this novel pump. (An Evaluation of the Safety and Performance of the Aortix System for Intra-Aortic Mechanical Circulatory Support in Patients with Cardiorenal Syndrome [The Aortix CRS Pilot Study]; NCT04145635).

The Effects of Nitric Oxide Synthase Inhibition on Epinephrine-Induced Arrhythmia and Myocardial Damage

We have recently reported that methylene blue (MethyB) was able to inhibit epinephrine-induced arrhythmias and cardiac muscle injury. In this study, we investigated the effect of nitric oxide synthase inhibition by NG-nitro-L-arginine methyl ester (L-NAME) on cardiac arrhythmias, and myocardial damage induced by epinephrine in rats. Whether nitric oxide inhibition would affect the antiarrhythmic and cardiac protective actions of MethyB was also examined. L-NAME (40 mg/kg), L-arginine (200 mg/kg) + L-NAME, or MethyB (100 mg/kg) + L-NAME were given intraperitoneally (i.p.). Cardiac arrhythmia was then induced with intravenous (i.v.) injection of 10 μg/kg epinephrine. Results showed that epinephrine injection caused marked bradycardia (221.0 ± 1.37 vs. 409.4 ± 3.18 beats/min), shortened QTc interval (0.096 ± 0.0093 vs. 0.177 ± 0.0008 s), increased QRS duration (0.040 ± 0.0035 vs. 0.0185 ± 0.0002 s), decreased R wave amplitude (0.176 ± 0.0051 vs. 0.21 ± 0.0009 mv), ST segment height (-0.026 ± 0.007 vs. -0.002 ± 0.0005 mv), and induced ventricular extrasystoles. L-NAME given to untreated control rats resulted in a decrease in heart rate (288.2 ± 0.88 vs. 409.4 ± 3.18 beats/min), and increased R wave amplitude (0.436 ± 0.004 vs. 0.21 ± 0.0009 mv) compared to controls. L-NAME did not cause extrasystoles in untreated control rats but significantly increased the number of extrasystoles and duration of arrhythmia in the epinephrine-treated group. The administration of L-arginine (200 mg/kg, i.p.) to epinephrine plus L-NAME-treated rats resulted in increased heart rate and markedly decreased the number of extrasystoles and duration of arrhythmia. Methylene blue given at 100 mg/kg to rats treated with epinephrine and L-NAME caused a marked increase in heart rate. It also normalized QRS duration, prevented ST segment depression, markedly suppressed ventricular extrasystoles, and decreased the duration of arrhythmia compared with either epinephrine or L-NAME plus epinephrine-treated groups. Epinephrine injection caused disorganization, and necrosis of cardiac cells, interstitial hemorrhage, and cellular infiltrations. These changes were markedly improved by treatment with either L-NAME or L-NAME/MethyB. These results suggest that (i) inhibiting nitric oxide synthase by L-NAME increases epinephrine-induced arrhythmia which is inhibited by L-arginine or MethyB; (ii) either L-NAME alone or in combination with MethyB prevented cardiac muscle injury induced by epinephrine; (iii) L-NAME did not prevent the cardiac protective and antiarrhythmic actions of MethyB.

6-Nitrodopamine Is the Most Potent Endogenous Positive Inotropic Agent in the Isolated Rat Heart

BACKGROUND

6-nitrodopamine released from rat isolated atria exerts positive chronotropic action, being more potent than noradrenaline, adrenaline, and dopamine. Here, we determined whether 6-nitrodopamine is released from rat isolated ventricles (RIV) and modulates heart inotropism.

METHODS

Catecholamines released from RIV were quantified by LC-MS/MS and their effects on heart inotropism were evaluated by measuring left ventricular developed pressure (LVDP) in Langendorff's preparation.

RESULTS

6-nitrodopamine was the major released catecholamine from RIV. Incubation with L-NAME (100 µM), but not with tetrodotoxin (1 µM), caused a significant reduction in 6-nitrodopamine basal release. 6-nitrodopamine release was significantly reduced in ventricles obtained from L-NAME chronically treated animals. 6-nitrodopamine (0.01 pmol) caused significant increases in LVDP and dP/dtmax, whereas dopamine and noradrenaline required 10 pmol, and adrenaline required 100 pmol, to induce similar increases in LVDP and dP/dtmax. The infusion of atenolol (10 nM) reduced basal LVDP and blocked the increases in LVDP induced by 6-ND (0.01 pmol), without affecting the increases in LVDP induced by 10 nmol of dopamine and noradrenaline and that induced by adrenaline (100 nmol).

CONCLUSIONS

6-nitrodopamine is the major catecholamine released from rat isolated ventricles. It is 1000 times more potent than dopamine and noradrenaline and is selectively blocked by atenolol, indicating that 6-ND is a main regulator of heart inotropism.

Prehospital Administration of Norepinephrine and Epinephrine for Shock after Resuscitation from Cardiac Arrest

INTRODUCTION

Shock after resuscitation from out-of-hospital cardiac arrest (OHCA) is often treated with vasopressors. We examined whether infusion of epinephrine versus norepinephrine was associated with prehospital rearrest and neurologically favorable survival among OHCA patients.

METHODS

This retrospective study included OHCA cases in Seattle, Washington from 2014-2021 who had return of spontaneous circulation (ROSC) followed by vasopressor infusion. Our primary exposure was infusion of epinephrine or norepinephrine. Our primary outcome was prehospital rearrest. Secondary outcomes included survival and neurologically favorable outcome (Cerebral Performance Category score of 1 or 2). We used multivariable logistic regression to test associations between exposures and outcomes adjusting for key covariates.

RESULTS

Of 451 OHCA patients with ROSC followed by vasopressor infusion, 253 (56%) received norepinephrine and 198 (44%) received epinephrine infusions. Those who received epinephrine were older (median 66 [interquartile ranges {IQR} 53-79] vs 63 [IQR 47-75] years), but otherwise had similar baseline characteristics. Patients who received epinephrine were twice as likely to rearrest (55% vs 25%). After adjustment, the difference in rearrest rates between epinephrine and norepinephrine persisted (OR 3.28, 95%CI 2.25-5.08), and the odds of pulses at hospital arrival were lower in the epinephrine group (OR 0.52 95%CI 0.32-0.83). After adjustment, there was no difference in neurologically favorable survival, survival to hospital admission, or survival to discharge.

CONCLUSION

Patients who received epinephrine infusions after ROSC suffered prehospital rearrest more frequently than those who received norepinephrine. Survival and neurological status at hospital discharge were similar. Future trials should examine the optimal approach to hemodynamic management for post-OHCA shock.

Safety and Outcomes of Peripherally Administered Vasopressor Infusion in Patients Admitted with Shock to an Intensive Cardiac Care Unit-A Single-Center Prospective Study

BACKGROUND

Vasopressors are frequently utilized for blood pressure stabilization in patients with cardiogenic shock (CS), although with a questionable benefit. Obtaining central venous access is time consuming and may be associated with serious complications. Hence, we thought to evaluate whether the administration of vasopressors through a peripheral venous catheter (PVC) is a safe and effective alternative for the management of patients with CS presenting to the intensive cardiovascular care unit (ICCU).

METHODS

A prospective single-center study was conducted to compare the safety and outcomes of vasopressors administered via a PVC vs. a central venous catheter (CVC) in patients presenting with CS over a 12-month period.

RESULTS

A total of 1100 patients were included; of them, 139 (12.6%) required a vasopressor treatment due to shock, with 108 (78%) treated via a PVC and 31 (22%) treated via a CVC according to the discretion of the treating physician. The duration of the vasopressor administration was shorter in the PVC group compared with the CVC group (2.5 days vs. 4.2 days, respectively, p < 0.05). Phlebitis and the extravasation of vasopressors occurred at similar rates in the PVC and CVC groups (5.7% vs. 3.3%, respectively, p = 0.33; 0.9% vs. 3.3%, respectively, p = 0.17). Nevertheless, the bleeding rate was higher in the CVC group compared with the PVC group (3% vs. 0%, p = 0.03).

CONCLUSIONS

The administration of vasopressor infusions via PVC for the management of patients with CS is feasible and safe in patients with cardiogenic shock. Further studies are needed to establish this method of treatment.

Omecamtiv mecarbil in precision-cut living heart failure slices: A story of a double-edged sword

Heart failure (HF) is a rapidly growing pandemic while medical treatment options remain limited. Omecamtiv mecarbil (OM) is a novel HF drug that directly targets the myosin heads of the cardiac muscle. This study used living myocardial slices (LMS) from patients with HF to evaluate the direct biomechanical effects of OM as compared to dobutamine. LMS were produced from patients with end-stage HF undergoing cardiac transplantation or left ventricular assist device implantation and cultured under electromechanical stimulation (diastolic preload: ca. 1 mN, stimulation frequency: 0.5 Hz). Dobutamine and omecamtiv mecarbil (OM) were administered on consecutive days and biomechanical effects were continuously recorded with dedicated force transducers. OM and dobutamine significantly increased contractile force to a similar maximum force, but OM also increased median time-to-peak with 48 % (p = 0.046) and time-to-relaxation with 68 % (p = 0.045). OM administration led to impaired relaxation of HF LMS with increasing stimulation frequencies, which was not observed with dobutamine. Furthermore, the functional refractory period was significantly shorter after administration of OM compared to dobutamine (235 ms (200-265) vs. 270 ms (259-283), p = 0.035). In conclusion, OM increased contractile force and systolic duration of HF LMS, indicating an improvement in cardiac function and normalization of systolic time intervals in patients with HF. Conversely, OM slowed relaxation, which could lead to diastolic filling abnormalities. As such, OM showed benefits on systolic function on one hand but potential hindrances of diastolic function on the other hand.

Lack of Association of Initial Vasopressor Dosing with Survival and Cardiac Re-Arrest Likelihood After Return of Spontaneous Circulation

BACKGROUND

Cardiac arrest occurs in approximately 350,000 patients outside the hospital and approximately 30,000 patients in the emergency department (ED) annually in the United States. When return of spontaneous circulation (ROSC) is achieved, hypotension is a common complication. However, optimal dosing of vasopressors is not clear.

OBJECTIVE

The objective of this study was to determine if initial vasopressor dosing was associated with cardiac re-arrest in patients after ROSC.

METHODS

This was a retrospective, single-center analysis of adult patients experiencing cardiac arrest prior to arrival or within the ED. Patients were assigned to one of four groups based on starting dose of vasopressor: low dose (LD; < 0.25 µg/kg/min), medium dose (MD; 0.25-0.49 µg/kg/min), high dose (HD; 0.5-0.99 µg/kg/min), and very high dose (VHD; ≥ 1 µg/kg/min). Data collection was performed primarily via manual chart review of medical records. The primary outcome was incidence of cardiac re-arrest within 1 h of vasopressor initiation. Multivariate logistic regression analysis was conducted to identify any covariates strongly associated with the primary outcome.

RESULTS

No difference in cardiac re-arrest incidence was noted between groups. The VHD group was significantly more likely to require a second vasopressor (p = 0.003). The HD group had lower survival rates to hospital discharge compared with the LD and MD groups (p = 0.0033 and p = 0.0147). In the multivariate regression, longer duration of pre-vasopressor re-arrests and hyperkalemic cardiac arrest etiology were significant predictors of cardiac re-arrest after vasopressor initiation.

CONCLUSIONS

Initial vasopressor dosing was not found to be associated with risk of cardiac re-arrest or, conversely, risk of adverse events.

Heart rate and heart rate variability as a prognosticating feature for functional outcome after cardiac arrest: A scoping review

Background

Despite significant progress in cardiopulmonary resuscitation and post-cardiac arrest care, favorable outcome in out-of hospital sudden cardiac arrest patients remains low. One of the main reasons for mortality in these patients is withdrawal of life-sustaining treatment. There is a need for precise and equitable prognostication tools to support families in avoiding premature or inappropriate WLST. Heart rate (HR) and heart rate variability (HRV) have been noted for their association with outcome, and are positioned to be a useful modality for prognostication.

Objectives

The aim of this scoping review is to rigorously explore which electrocardiography features have been shown to predict functional outcome in post-cardiac arrest patients.

Methods

The search was performed in Pubmed, EMBASE, and SCOPUS for studies published from January 1, 2011, to September 29, 2022, including papers in English or Korean.

Results

Seven studies were included with a total of 1359 patients. Four studies evaluated HR, one study evaluated RR inverval, and two studies evaluated HRV. All studies were retrospective, with 3 multi-center and 4 single-center studies. All seven studies were inclusive of patients who underwent targeted temperature management (TTM) after cardiac arrest, and two studies included patients without TTM. Five studies used cerebral performance category to assess functional outcome, two studies used Glasgow outcome score, and one study used modified Rankin scale. Three studies measured outcome at hospital discharge, one study measured outcome at 14 days after return of spontaneous circulation, two studies measured outcome after 3 months, and one after 1 year. In all studies that evaluated HR, lower HR was associated with favorable functional outcome. Two studies found that higher complexity of HRV was associated with favorable functional outcome.

Conclusion

HR and HRV showed clear associations with functional outcome in patients after CA, but cinilcial utility for prognostication is uncertain.