Basic mechanisms in cardiogenic shock: part 1-definition and pathophysiology

Evaluating the prognostic value of systemic immune-inflammatory index in patients with acute decompensated heart failure

AIMS

The value of the systemic immune-inflammatory index (SII) in assessing adverse outcomes in various cardiovascular diseases has been extensively discussed. This study aims to evaluate the predictive value and risk stratification ability of SII for 30 day mortality in patients with acute decompensated heart failure (ADHF).

METHODS

This analysis included 1452 patients hospitalized for ADHF, all the participants being part of the China Jiangxi-acute decompensated heart failure1 project. The risk stratification capability of the SII in patients with ADHF, as well as its correlation with the 30 day mortality risk among ADHF patients, was evaluated utilizing Kaplan-Meier survival analysis and multivariable Cox regression models. A restricted cubic spline was employed to model the dose-response relationship between the two, and the receiver operating characteristic curve was utilized to assess the predictive ability of SII for 30 day mortality.

RESULTS

The Kaplan-Meier analysis revealed that the risk of mortality in the high SII group (SII ≥ 980 × 109/L) was significantly greater than that in the low SII group (SII < 980 × 109/L, log-rank P < 0.001). After adjusting for various confounding factors, a higher SII was associated with an increased risk of 30 day mortality in ADHF patients [hazard ratio (HR) = 2.03, 95% confidence interval (CI): 1.34-3.08]. Further restricted cubic spline analysis revealed a non-linear dose-response relationship between the two (P for non-linear = 0.006). Receiver operating characteristic analysis demonstrated that SII had a high accuracy in predicting 30 day mortality events in ADHF patients (AUC = 0.7479), and the optimal predictive threshold was calculated to be 980 × 109/L, a sensitivity of 0.7547 and a specificity of 0.7234.

CONCLUSIONS

This study found a significant positive association between SII and 30 day all-cause mortality in ADHF patients. We determined the SII cut-off point for predicting 30 day all-cause mortality in patients with ADHF to be 980 × 109/L.

Cardiogenic shock as a health issue. Physiology, classification, and detection

Cardiogenic shock (CS) is a heterogeneous syndrome with high mortality and a growing incidence. It is characterized by an imbalance between the tissue oxygen demands and the capacity of the cardiovascular system to meet these demands, due to acute cardiac dysfunction. Historically, acute coronary syndromes have been the primary cause of CS. However, non-ischemic cases have seen a rise in incidence. The pathophysiology involves ischemic damage of the myocardium and a sympathetic, renin-angiotensin-aldosterone system and inflammatory response, perpetuating the situation of tissue hypoperfusion and ultimately leading to multiorgan dysfunction. The characterization of CS patients through a triaxial assessment and the widespread use of the Society for Cardiovascular Angiography and Interventions (SCAI) scale has allowed standardization of the severity stratification of CS; this, coupled with early detection and the "hub and spoke" approach, could contribute to improving the prognosis of these patients.

Association of systemic inflammation with shock severity, 30-day mortality, and therapy response in patients with cardiogenic shock

BACKGROUND

Mortality in cardiogenic shock (CS) remains high even when mechanical circulatory support (MCS) restores adequate circulation. To detect a potential contribution of systemic inflammation to shock severity, this study determined associations between C-reactive protein (CRP) concentrations and outcomes in patients with CS.

METHODS

Unselected, consecutive patients with CS and CRP measurements treated at a single large cardiovascular center between 2009 and 2019 were analyzed. Adjusted regression models were fitted to evaluate the association of CRP with shock severity, 30-day in-hospital mortality and treatment response to MCS.

RESULTS

The analysis included 1116 patients [median age: 70 (IQR 58-79) years, 795 (71.3%) male, lactate 4.6 (IQR 2.2-9.5) mmol/l, CRP 17 (IQR 5-71) mg/l]. The cause of CS was acute myocardial infarction in 530 (48%) patients, 648 (58%) patients presented with cardiac arrest. Plasma CRP concentrations were equally distributed across shock severities (SCAI stage B-E). Higher CRP concentrations were associated with 30-day in-hospital mortality (8% relative risk increase per 50 mg/l increase in CRP, range 3-13%; p < 0.001), even after adjustment for CS severity and other potential confounders. Higher CRP concentrations were only associated with higher mortality in patients not treated with MCS [hazard ratio (HR) for CRP > median 1.50; 95%-CI 1.21-1.86; p < 0.001], but not in those treated with MCS (HR for CRP > median 0.92; 95%-CI 0.67-1.26; p = 0.59; p-interaction = 0.01).

CONCLUSION

Elevated CRP concentrations are associated with increased 30-day in-hospital mortality in unselected patients with cardiogenic shock. The use of mechanical circulatory support attenuates this association.

Population pharmacokinetics of fluconazole in critically ill patients receiving extracorporeal membrane oxygenation and continuous renal replacement therapy: an ASAP ECMO study

This multicenter study describes the population pharmacokinetics (PK) of fluconazole in critically ill patients receiving concomitant extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT) and includes an evaluation of different fluconazole dosing regimens for achievement of target exposure associated with maximal efficacy. Serial blood samples were obtained from critically ill patients on ECMO and CRRT receiving fluconazole. Total fluconazole concentrations were measured in plasma using a validated chromatographic assay. A population PK model was developed and Monte Carlo dosing simulations were performed using Pmetrics in R. The probability of target attainment (PTA) of various dosing regimens to achieve fluconazole area under the curve to minimal inhibitory concentration ratio (AUC0-24/MIC) >100 was estimated. Eight critically ill patients receiving concomitant ECMO and CRRT were included. A two-compartment model including total body weight as a covariate on clearance adequately described the data. The mean (±standard deviation, SD) clearance and volume of distribution were 2.87 ± 0.63 L/h and 15.90 ± 13.29 L, respectively. Dosing simulations showed that current guidelines (initial loading dose of 12 mg/kg then 6 mg/kg q24h) achieved >90% of PTA for a MIC up to 1 mg/L. None of the tested dosing regimens achieved 90% of PTA for MIC above 2 mg/L. Current fluconazole dosing regimen guidelines achieved >90% PTA only for Candida species with MIC <1 mg/L and thus should be only used for Candida-documented infections in critically ill patients receiving concomitant ECMO and CRRT. Total body weight should be considered for fluconazole dose.

Age‑adjusted Charlson comorbidity index and in‑hospital mortality in critically ill patients with cardiogenic shock: A retrospective cohort study

Evidence regarding the relationship between age-adjusted Charlson comorbidity index (ACCI) and in-hospital mortality is limited. Therefore, the present study investigated whether there was an independent association between ACCI and in-hospital mortality in critically ill patients with cardiogenic shock (CS) after adjusting for other covariates (age, sex, history of disease, scoring system, in-hospital management, vital signs at presentation, laboratory findings and vasopressors). ACCI, calculated retrospectively after hospitalization between 2008 and 2019, was derived from intensive care unit (ICU) admissions at the Beth Israel Deaconess Medical Center (Boston, MA, USA). Patients with CS were classified into two categories based on predefined ACCI scores (low, <8; high, ≥8). Based on baseline ACCI, the risk of in-hospital mortality in patients with CS was calculated using a multivariate Cox proportional risk model, and the threshold effect was calculated using a two-piece linear regression model. The in-hospital mortality rate was ~1.5 times greater in the ACCI high group compared with that in the ACCI low group [hazard ratio (HR)=1.45; 95% confidence interval (CI), 1.14-1.86]. Additional analysis showed that ACCI had a curvilinear association with in-hospital mortality risk in patients with CS, with a saturation effect predicted at 4.5. When ACCI was >4.5, the risk of in-hospital CS death increased significantly with increasing ACCI (HR=1.122; 95% CI, 1.054-1.194). Overall, ACCI was an independent predictor of in-hospital mortality in ICU patients with CS. A non-linear relationship was revealed between ACCI and in-hospital mortality, where in-hospital mortality increased significantly when ACCI was >4.5.

Association between short-term systemic use of glucocorticoids and prognosis of cardiogenic shock: a retrospective analysis

OBJECTIVE

To investigate the prescription rate of short-term systemic use of glucocorticoids during hospitalization in patients with cardiogenic shock (CS), and outcomes related with glucocorticoid use.

METHODS

We extracted patients' information from the Medical Information Mart for Intensive Care IV version 2.0 (MIMIC-IV v2.0) database. The primary endpoint was 90-day all-cause mortality. Secondary safety endpoints were infection identified by bacterial culture and at least one episode of hyperglycemia after ICU admission. Propensity score matching (PSM) was used to balance baseline characteristics. The difference in cumulative mortality rate between these treated with and without glucocorticoids was assessed by Kaplan-Meier curve with log-rank test. Independent risk factors for endpoints were identified by Cox or Logistic regression analysis.

RESULTS

A total of 1528 patients were enrolled, and one-sixth of these patients received short-term systemic therapy of glucocorticoids during hospitalization. These conditions, including rapid heart rate, the presence of rheumatic disease, chronic pulmonary disease and septic shock, high lactate level, the requirements of mechanical ventilation and continuous renal replacement therapy, were associated with an increase in glucocorticoid administration (all P ≤ 0.024). During a follow-up of 90 days, the cumulative mortality rate in patients treated with glucocorticoids was significantly higher than that in these untreated with glucocorticoids (log-rank test, P < 0.001). Multivariable Cox regression analysis showed that glucocorticoid use (hazard ratio 1.48, 95% confidence interval [CI] 1.22-1.81; P < 0.001) was independently associated with an increased risk for 90-day all-cause mortality. This result was consistent irrespective of age, gender, the presence of myocardial infarction, acute decompensated heart failure and septic shock, and inotrope therapy, but was more evident in low-risk patients as assessed by ICU scoring systems. Additionally, multivariable Logistic regression analysis showed that glucocorticoid exposure was an independent predictor of hyperglycemia (odds ratio 2.14, 95% CI 1.48-3.10; P < 0.001), but not infection (odds ratio 1.23, 95% CI 0.88-1.73; P = 0.221). After PSM, glucocorticoid therapy was also significantly related with increased risks of 90-day mortality and hyperglycemia.

CONCLUSIONS

Real-world data showed that short-term systemic use of glucocorticoids was common in CS patients. Importantly, these prescriptions were associated with increased risks of adverse events.

Microcirculatory dysfunction in cardiogenic shock

Cardiogenic shock is usually defined as primary cardiac dysfunction with low cardiac output leading to critical organ hypoperfusion, and tissue hypoxia, resulting in high mortality rate between 40% and 50% despite recent advances. Many studies have now evidenced that cardiogenic shock not only involves systemic macrocirculation, such as blood pressure, left ventricular ejection fraction, or cardiac output, but also involves significant systemic microcirculatory abnormalities which seem strongly associated with the outcome. Although microcirculation has been widely studied in the context of septic shock showing heterogeneous alterations with clear evidence of macro and microcirculation uncoupling, there is now a growing body of literature focusing on cardiogenic shock states. Even if there is currently no consensus regarding the treatment of microcirculatory disturbances in cardiogenic shock, some treatments seem to show a benefit. Furthermore, a better understanding of the underlying pathophysiology may provide hypotheses for future studies aiming to improve cardiogenic shock prognosis.