ACE-inhibitor therapy and survival among patients with multiorgan dysfunction syndrome (MODS) of cardiac and non-cardiac origin

Effect of different single and combined antihypertensive drug regimens on the mortality of critical care patients

Objective

To investigate the effect of different single and combined pre-admission antihypertensive drug regimens on the prognosis of critically ill patients.

Methods

We performed a retrospective cohort study using data from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. All initial ICU admission records of patients with hypertension and previous antihypertensive exposure before ICU admission were included. Our primary outcome was 90-day mortality. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to balance the distribution of baseline characteristics. Logistic regression analysis and subgroup analysis were performed to determine the independent effect of different single and combined antihypertensive drug regimens on 90-day mortality.

Results

A total of 13,142 patients were included in the final analysis. The 90-day mortality rate in the combined groups is lower than that in the single therapy group (10.94% vs 11.12%), but no statistical significance was found in the original cohort (p = 0.742). After adjustment for potential confounders, the significantly decreased 90-day mortality rate was found in the combined groups (10.78% vs 12.65%, p = 0.004 in PSM; 10.34% vs 11.90%, p = 0.007). Patients who were exposed to either ACEIs or ARBs had a better prognosis than those not exposed (7.19% vs 17.08%, p < 0.001 in single antihypertensive groups; 8.14% vs18.91%, p < 0.001 in combined antihypertensive groups). The results keep robustness in the PSM and IPTW cohorts. In the logistic regression model analysis, combined therapy was associated with a 12%-20% reduced risk of 90-day death after adjusting potential confounders (OR 0.80-0.88, all p < 0.05), while exposure to ACEIs or ARBs was associated with the decreased risk of 90-day death by 52%-62% (OR 0.38-0.48, all p < 0.001) and 40%-62% (OR 0.38-0.60, all p < 0.001) in the single and combined therapy groups, respectively. The results were still robust to subgroup analysis.

Conclusions

Pre-admission combined antihypertensive therapy is associated with a significantly lower risk of death than exposure to single antihypertensives in critically ill patients. Meanwhile, either ACEIs or ARBs seem to be the optimal candidates for both single and combined therapy. Further high-quality trials are needed to confirm our findings.

Early heart rate variability evaluation enables to predict ICU patients' outcome

Heart rate variability (HRV) is a mean to evaluate cardiac effects of autonomic nervous system activity, and a relation between HRV and outcome has been proposed in various types of patients. We attempted to evaluate the best determinants of such variation in survival prediction using a physiological data-warehousing program. Plethysmogram tracings (PPG) were recorded at 75 Hz from the standard monitoring system, for a 2 h period, during the 24 h following ICU admission. Physiological data recording was associated with metadata collection. HRV was derived from PPG in either the temporal and non-linear domains. 540 consecutive patients were recorded. A lower LF/HF, SD2/SD1 ratios and Shannon entropy values on admission were associated with a higher ICU mortality. SpO2/FiO2 ratio and HRV parameters (LF/HF and Shannon entropy) were independent correlated with mortality in the multivariate analysis. Machine-learning using neural network (kNN) enabled to determine a simple decision tree combining the three best determinants (SDNN, Shannon Entropy, SD2/SD1 ratio) of a composite outcome index. HRV measured on admission enables to predict outcome in the ICU or at Day-28, independently of the admission diagnosis, treatment and mechanical ventilation requirement.

Trial registration: ClinicalTrials.gov identifier NCT02893462.

Loss of Hepatic Angiotensinogen Attenuates Sepsis-Induced Myocardial Dysfunction

Rationale: The renin-angiotensin system (RAS) is a complex regulatory network that maintains normal physiological functions. The role of the RAS in sepsis-induced myocardial dysfunction (SIMD) is poorly defined. Angiotensinogen (AGT) is the unique precursor of the RAS and gives rise to all angiotensin peptides. The effects and mechanisms of AGT in development of SIMD have not been defined. Objective: To determine a role of AGT in SIMD and investigate the underlying mechanisms. Methods and Results: Either intraperitoneal injection of lipopolysaccharide (LPS) or cecal ligation and puncture (CLP) significantly enhanced AGT abundances in liver, heart, and plasma. Deficiency of hepatocyte-derived AGT (hepAGT), rather than cardiomyocyte-derived AGT (carAGT), alleviated septic cardiac dysfunction in mice and prolonged survival time. Further investigations revealed that the effects of hepAGT on SIMD were partially associated with augmented angiotensin II (AngII) production in circulation. In addition, hepAGT was internalized by LDL receptor-related protein 1 (LRP1) in cardiac fibroblasts (CF), and subsequently activated NLRP3 inflammasome via an AngII-independent pathway, ultimately promoting SIMD by suppressing Sarco(endo)plasmic reticulum Ca(2+)-ATPase 2a (SERCA2a) abundances in cardiomyocytes (CM). Conclusions: HepAGT promoted SIMD via both AngII-dependent and AngII-independent pathways. We identified a liver-heart axis by which AGT regulated development of SIMD. Our study may provide a potential novel therapeutic target for SIMD.

The effect of continuous blood purification on P38MAPK signaling pathway in patients with multiple organ dysfunction syndrome

OBJECTIVE

The aim of the study was to investigate the role of p38MAPK signaling pathway in patients with multiple organ dysfunction syndrome treated with continuous blood purification.

METHODS

Blood samples were obtained to analyze the protein level of inflammatory factors (IL-1, IL-8, IL-10, and TNF-α) and phosphorylated p38MAPK by utilizing ELISA assay and Western blotting, respectively. The relative mRNA level of iNOS was detected by using RT-PCR. In vitro study was conducted in Caco-2 cells, which were treated with serum from patients subjected to continuous blood purification. Serum-induced inflammatory factors and phosphorylated p38MAPK were also analyzed in Caco-2 cells.

RESULTS

The protein levels of IL-1, IL-8, IL-10, and TNF-α were significantly decreased in Caco-2 cells treated with serum obtained from patients who were subjected to continuous blood purification therapy at the time course of 12 and 24 hours. A drastic decrease (P < 0.05) was observed in the level of IL-8 and TNF-α after continuous blood purification therapy in the patients treated with continuous blood purification therapy compared with control group.

CONCLUSION

Our study conducted in vivo and in vitro demonstrated that the continuous blood purification therapy could ameliorate the inflammatory response via activating the p38MAPK signaling pathway.

Heart rate variability in critical care medicine: a systematic review

BACKGROUND

Heart rate variability (HRV) has been used to assess cardiac autonomic activity in critically ill patients, driven by translational and biomarker research agendas. Several clinical and technical factors can interfere with the measurement and/or interpretation of HRV. We systematically evaluated how HRV parameters are acquired/processed in critical care medicine.

METHODS

PubMed, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (1996-2016) were searched for cohort or case-control clinical studies of adult (>18 years) critically ill patients using heart variability analysis. Duplicate independent review and data abstraction. Study quality was assessed using two independent approaches: Newcastle-Ottowa scale and Downs and Black instrument. Conduct of studies was assessed in three categories: (1) study design and objectives, (2) procedures for measurement, processing and reporting of HRV, and (3) reporting of relevant confounding factors.

RESULTS

Our search identified 31/271 eligible studies that enrolled 2090 critically ill patients. A minority of studies (15; 48%) reported both frequency and time domain HRV data, with non-normally distributed, wide ranges of values that were indistinguishable from other (non-critically ill) disease states. Significant heterogeneity in HRV measurement protocols was observed between studies; lack of adjustment for various confounders known to affect cardiac autonomic regulation was common. Comparator groups were often omitted (n = 12; 39%). This precluded meaningful meta-analysis.

CONCLUSIONS

Marked differences in methodology prevent meaningful comparisons of HRV parameters between studies. A standardised set of consensus criteria relevant to critical care medicine are required to exploit advances in translational autonomic physiology.

Correlations between ACE single nucleotide polymorphisms and prognosis of patients with septic shock

The aim of the present study is to investigate association between septic shock (SS) and angiotensin I-converting enzyme (ACE) single nucleotide polymorphisms (SNPs). From October 2009 to December 2016, 238 SS patients and 242 healthy individuals were selected for our study. ACE activity was detected, ACE rs4291 and rs4646994 polymorphisms were detected using PCR-restriction fragment length polymorphism (PCR-RFLP). The Kaplan–Meier survival curve was employed to evaluate the association between ACE SNPs and patients’ survival and univariate and multivariate analyses to estimate risk factors for SS. ACE activity in the case group was increased in comparison with the control group. Allele and genotype frequencies of rs4291 and rs4646994 were different between the case and control groups. The TT genotype frequency of the rs4291 polymorphisms and the DD genotype of the rs4646994 polymorphisms of the case group were higher than those in the control group. The AT and TT genotypes indicated a significant elevation of ACE activity than the AA genotype, while a significant decline was found in the DI and II genotypes in comparison with the DI genotype. Patients with TT or DD genotypes had increased fatality rate within 7 and 30 days when compared with those with non-TT or non-DD genotypes. Lower sepsis-related organ failure assessment (SOFA) scores, rs4291, serum ACE and rs4646994 were all considered as risky factors for SS patients. The study demonstrates that TT genotype of rs4291 or DD genotype of rs4646994 may be indicative of a higher risk of SS and a poorer prognosis in SS patients.

Salvianolic acid A protects against vascular endothelial dysfunction in high-fat diet fed and streptozotocin-induced diabetic rats

Salvianolic acid A (SalA) is one of the main active ingredients of Salvia miltiorrhizae. The objective of this study was to evaluate the effect of SalA on the diabetic vascular endothelial dysfunction (VED). The rats were given a high-fat and high-sucrose diet for 1 month followed by intraperitoneal injection of streptozotocin (30 mg/kg). The diabetic rats were treated with SalA (1 mg/kg, 90% purity) orally for 10 weeks after modeling, and were given a high-fat diet. Contractile and relaxant responses of aorta rings as well as the serum indications were measured. Our results indicated that SalA treatment decreased the level of serum Von Willebrand factor and ameliorated acetylcholine-induced relaxation and KCl-induced contraction in aorta rings of the diabetic rats. SalA treatment also reduced the serum malondialdehyde, the content of aortic advanced glycation end products (AGEs), and the nitric oxide synthase (NOS) activity as well as the expression of endothelial NOS protein in the rat aorta. Exposure of EA.hy926 cells to AGEs decreased the cell viability and changed the cell morphology, whereas SalA had protective effect on AGEs-induced cellular vitality. Our data suggested that SalA could protect against vascular VED in diabetes, which might attribute to its suppressive effect on oxidative stress and AGEs-induced endothelial dysfunction.