Epigenetic and phenotypic characterization of iPSCs-derived smooth muscle cells: towards a cellular model for complex arterial diseases

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): European Research Council

Introduction

Smooth muscle cells (SMCs) capacity to switch between proliferative (synthetic) and quiescent (contractile) phenotypes is a widely studied mechanism in cardiovascular disease. Primary SMCs tend to lose many physiological features in culture, which makes the study of their contractile function challenging. Recently, an optimized protocol of induced pluripotent stem cells (iPSCs) differentiation into contractile SMCs was described.

Purpose

We aimed at obtaining a deep characterization of cellular phenotypes during the differentiation into synthetic or contractile SMCs, and evaluate these cellular models in the context of complex cardiovascular diseases.

Methods

We differentiated 4 human iPSC lines (2 males, 2 females) towards either contractile (Repsox induced) or synthetic (PDGF-BB/TGF-β induced) SMC phenotypes using a 24-days protocol (Figure). We performed RNA-Seq and assay for transposase accessible chromatin (ATAC)-Seq at 6 time points of differentiation. We compared gene expression and open chromatin profiles between them and to existing datasets of primary human SMCs and artery tissues. We characterized the extracellular matrix (matrisome) generated by SMCs using mass spectrometry.

Results

iPSCs derived SMCs showed expected morphology and positive expression of SMC markers. Synthetic SMCs exhibited greater capacity of proliferation, migration, lower contractility and calcium release capacity, compared to contractile SMCs. RNA-Seq results showed that multiple disease-associated genes involved in the contractile function of arteries, including smooth-muscle myosin heavy chain (MYH11), myosin light chain kinase (MYLK) and angiotensin type 1 receptor (AGTR1) genes, were highly expressed in contractile compared to synthetic SMCs. Interestingly, multiple genes coding for extracellular matrix components were also enriched in contractile SMCs. Matrisome characterization confirmed that contractile SMCs generated a rich extracellular matrix, compared to synthetic cells.  Analysis of transcriptomic and open chromatin profiles suggests contractile SMCs retained a higher level of activity for transcription factors involved in vascular smooth muscle development. Synthetic SMCs however presented open chromatin profiles similar to cultured primary SMCs. Open chromatin regions of contractile SMCs were highly enriched for variants associated with vascular diseases such as hypertension and intracranial aneurysm, whereas synthetic SMCs were more enriched for variants associated to peripheral artery disease and aortic aneurysm.

Conclusions

Differentiation of SMCs from iPSCs using two complementary protocols provides valid cellular models suitable for the study of a variety of vascular diseases. Utilization of these cells in combination with genome-editing tools is a promising approach to the study of complex regulatory mechanisms at genetic risk loci while considering phenotypic variability of arterial cellular components.

Diagnosis and management of heart failure from hospital admission to discharge: A practical expert guidance

Heart failure (HF) has high event rates, mortality, and is challenging to manage in clinical practice. Clinical management is complicated by complex therapeutic strategies in a population with a high prevalence of comorbidity and general frailty. In the last four years, an abundance of research has become available to support multidisciplinary management of heart failure from within the hospital through to discharge and primary care as well as supporting diagnosis and comorbidity management. Within the hospital setting, recent evidence supports sacubitril-valsartan combination in frail, deteriorating or de novo patients with LVEF≤40%. Furthermore, new strategies such as SGLT2 inhibitors and vericiguat provide further benefit for patients with decompensating HF. Studies with tafamidis report major clinical benefits specifically for patients with ATTR cardiac amyloidosis, a remaining underdiagnosed and undertreated disease. New evidence for medical interventions supports his bundle pacing to reduce QRS width and improve haemodynamics as well as ICD defibrillation for non-ischemic cardiomyopathy. The Mitraclip reduces hospitalisations and mortality in patients with symptomatic, secondary mitral regurgitation and ablation reduces mortality and hospitalisations in patients with paroxysmal and persistent atrial fibrillation. In end-stage HF, the 2018 French Heart Allocation policy should improve access to heart transplants for stable, ambulatory patients and, mechanical circulatory support should be considered to avoid deteriorating on the waiting list. In the community, new evidence supports that improving discharge education, treatment and patient support improves outcomes. The authors believe that this review fills the gap between the guidelines and clinical practice and provides practical recommendations to improve HF management.

Meta-analysis of sample-level dbGaP data reveals novel shared genetic link between body height and Crohn's disease

To further explore genetic links between complex traits, we developed a comprehensive framework to harmonize and integrate extensive genotype and phenotype data from the four well-characterized cohorts with the focus on cardiometabolic diseases deposited to the database of Genotypes and Phenotypes (dbGaP). We generated a series of polygenic risk scores (PRS) to investigate pleiotropic effects of loci that confer genetic risk for 19 common diseases and traits on body height, type 2 diabetes (T2D), and myocardial infarction (MI). In a meta-analysis of 20,021 subjects, we identified shared genetic determinants of Crohn's Disease (CD), a type of inflammatory bowel disease, and body height (p = 5.5 × 10^-5). The association of PRS-CD with height was replicated in UK Biobank (p = 1.1 × 10^-5) and an independent cohort of 510 CD cases and controls (1.57 cm shorter height per PRS-CD interquartile increase, p = 5.0 × 10^-3 and a 28% reduction in CD risk per interquartile increase in PRS-height, p = 1.1 × 10^-3, with the effect independent of CD diagnosis). A pathway analysis of the variants overlapping between PRS-height and PRS-CD detected significant enrichment of genes from the inflammatory, immune-mediated and growth factor regulation pathways. This finding supports the clinical observation of growth failure in patients with childhood-onset CD and demonstrates the value of using individual-level data from dbGaP in searching for shared genetic determinants. This information can help provide a refined insight into disease pathogenesis and may have major implications for novel therapies and drug repurposing.

Androgenic effects on ventricular repolarization: A translational study from the international pharmacovigilance database to iPSC-cardiomyocytes

BACKGROUND

Male hypogonadism, arising from a range of etiologies including androgen-deprivation therapies (ADTs), has been reported as a risk factor for acquired long-QT syndrome (aLQTS) and torsades de pointes (TdP). A full description of the clinical features of aLQTS associated with ADT and of underlying mechanisms is lacking.

METHODS

We searched the international pharmacovigilance database VigiBase for men (n=6 560 565 individual case safety reports) presenting with aLQTS, TdP, or sudden death associated with ADT. In cardiomyocytes derived from induced pluripotent stem cells from men, we studied electrophysiological effects of ADT and dihydrotestosterone.

RESULTS

Among subjects receiving ADT in VigiBase, we identified 184 cases of aLQTS (n=168) and/or TdP (n=68; 11% fatal), and 99 with sudden death. Of the 10 ADT drugs examined, 7 had a disproportional association (reporting odds ratio=1.4-4.7; P<0.05) with aLQTS, TdP, or sudden death. The minimum and median times to sudden death were 0.25 and 92 days, respectively. The androgen receptor antagonist enzalutamide was associated with more deaths (5430/31 896 [17%]; P<0.0001) than other ADT used for prostate cancer (4208/52 089 [8.1%]). In induced pluripotent stem cells, acute and chronic enzalutamide (25μM) significantly prolonged action potential durations (action potential duration at 90% when paced at 0.5Hz; 429.7±27.1 (control) versus 982.4±33.2 (acute, P<0.001) and 1062.3±28.9ms (chronic; P<0.001), and generated afterdepolarizations and/or triggered activity in drug-treated cells (11/20 acutely and 8/15 chronically). Enzalutamide acutely and chronically inhibited delayed rectifier potassium current, and chronically enhanced late sodium current. Dihydrotestosterone (30nM) reversed enzalutamide electrophysiological effects on induced pluripotent stem cells.

CONCLUSION

QT prolongation and TdP are a risk in men receiving enzalutamide and other ADTs.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03193138.

P5369Alpha-V integrin regulates the contribution of PW1+ cells to cardiac fibrosis

Background

Activated cardiac fibroblasts produce extracellular matrix proteins that accumulate during cardiac fibrosis. We have recently shown that PW1 is expressed in a subset of cardiac stromal cells and that cardiac PW1+ cells represent a cellular source of fibroblasts in the ischemic hearts.

Purpose

We aimed to further identify new cell surface markers expressed by cardiac PW1+ cells and to investigate their role in the fibrogenic behavior of these cells.

Methods and results

We first performed transcriptomic and proteomic profiling of FACS-isolated cardiac PW1+ from normal and ischemic hearts. RNA-sequencing output files were processed with bioinformatics algorithms to identify 378 specific cell-surface markers for cardiac PW1+ cells. By comparing these candidates with the proteomic profile, we then cross-identified 9 cell surface proteins primarily involved in cell motility, adhesion to the matrix, inflammatory response and response to wounding. One of these candidates (i.e., aV-integrin or CD51) was expressed in almost all cardiac PW1+ cells (93±1%), and was predominantly found in cells expressing PW1 in the myocardium. Cardiac PW1+ cells showed a predominant expression of aVβ1 complex which is known to mediate fibrosis through TGF-beta activation in a number of tissues. The transfer of isolated cardiac PW1+CD51+ cells into ischemic hearts was associated with fibrosis development. We further demonstrated that inhibition of aV-integrin in cardiac PW1+ cells reduces their profibrotic gene expression profile and their ability to differentiate into fibroblasts. Lastly, a pharmacological blockade of aV-integrin improved cardiac function and animal survival following myocardial infarction coupled with a reduced infarct size and fibrotic lesion.

Conclusions

These data identify a targetable pathway that regulates cardiac fibrosis in response to an ischemic injury and demonstrate that pharmacological inhibition of aV-integrin leads to reduced pathological outcomes following cardiac ischemia.

Acknowledgement/Funding

Fondation Leducq (grant 13CVD01, CardioStemNet project), Fédération Française de Cardiologie and Era-CVD (ANR-16-ECVD-0011-03, Clarify project)

1405Sequential nephron blockade with diuretics improves diastolic dysfunction in patients with resistant hypertension, a substudy a the PHARES trial

Introduction

Hypertension is one of the major contributors to cardiac diastolic dysfunction as observed in patients with heart failure and preserved ejection fraction. Different therapeutics strategies have been proposed to control blood pressure (BP) but their independent impact on cardiac function remain undetermined. In patients referred to our center for uncontrolled hypertension, we compared changes in cardiac parameters between two strategies consisting of sequential nephron blockade with intensive diuretics (NBD) or sequential renin angiotensin blockade (RAB).

Purpose

To determine evolution of BNP levels and echocardiographic (TTE) parameters of diastolic dysfunction according to strategies to control BP.

Methods

After 4-weeks treatment with 300mg irbesartan + 12.5mg hydrochlorothiazide + 5mg amlodipine, 140 patients with uncontrolled hypertension were randomized to either complete nephron blockade with sequential introduction of 25mg spironolactone, 20 to 40mg furosemide and 5mg amiloride (NBD group, n=74) or complete RAAS blockade with 5 to 10mg ramipril and 5 to 10mg bisoprolol (RAB group, n=67). BNP levels and TTE parameters according to ESC guidelines were assessed at baseline and week 12.

Results

BNP levels were not significantly different in the two groups at baseline (mean±SD 30.1±37.0pg/mL in NBD versus 22.6±22.3pg/mL in RAB, p=0.147) but significantly decreased in NBD at week 12 (20.1±22.7pg/mL in NBD versus 55.2±60.4pg/mL in RAB, p<0.0001). At week 12, only 9 (12%) patients in NBD presented BNP levels >35pg/mL versus 37 (55%) in RAB (p<0.001).

Concordantly, TTE parameters such as left ventricular end-diastolic diameter (mean±SD, 49±4mm in NBD and 52±5mm in RAB, p=0,004) and left atrial area (16.9±3.6cm2 in NBD and 19.1±3.7cm2 in RAB, p=0,003) improved significantly in NBD group. The proportions of patients presenting ≥2 criteria of diastolic dysfunction according to ESC guidelines in NBD and RAB group respectively were 31.2% and 19.3% at baseline vs. 3.1% and 32.2% after 12 weeks (p=0.001). In a multivariate analysis, NBD treatment was significantly associated with a decline in BNP levels (p<0.01) even after adjustment on daytime systolic BP lowering, heart rate, renal function, age and gender.

Conclusion

In patients with uncontrolled hypertension, intensive nephron blockade with sequential addition of diuretics improves markers of diastolic dysfunction independently of BP lowering.

P6590Androgenic effects on ventricular repolarization: a translational study from pharmacovigilance databases to iPSC-cardiomyocytes

Aim

Male hypogonadism, arising from various etiologies including androgen-deprivation therapies (ADT), has been reported as a risk-factor for acquired long-QT (aLQT) and Torsades de pointe (TdP). A full description of clinical features of aLQTS associated with ADT and of underlying mechanisms are lacking.

Method and results

We searched the WHO pharmacovigilance database for men (n=6,560,565) presenting with aLQT, TdP or sudden death (SD) associated with ADT. We identified 184 cases of aLQTS and/or TdP (11% fatal), and 99 with SD. Of the 10 ADT examined, 7 had a disproportional association (reporting-OR=1.4–4.7, p<0.05) with aLQT, TdP or SD. The minimum time to SD was 0.25 days. Enzalutamide (Enza, androgen antagonist) was associated with more deaths (17%, p<0.001) than other ADT used for prostate cancer (8.1%,Table). In cardiomyocytes derived from induced pluripotent stem cells (IPS-CMs) from men, we studied electrophysiological effects of enza and dihydrotestosterone (DHT). Acute and chronic enza (25μM) prolonged action potential durations (APD90-paced0.5Hz; 414±63 (control) vs. 951±67 (acute, p<0.01) and 1028±63msec (chronic, p<0.01), and generated early/delayed afterdepolarizations and/or triggered activity in drug treated cells (4/7 acute and 3/5 chronic). Enza acutely and chronically inhibited IKr, and chronically enhanced INa-L. DHT (30nM) reversed enza effects on IPS-CMs. In 7 men with aLQT and hypogonadism, ECGs showed low amplitude, bifid T-waves typical of IKr block which resolved with testosterone.

Table 1 ndeath/ntotal (%) aLQT TdP SD n/naLQTS±TdP±SD (%) with ADT considered suspect by reporter Leuprorelin 1,871/22,113 (8.5%) 33 16 18 28/55 (50.9%) Goserelin 471/5,821 (8.1%) 8 2 15 17/22 (77.3%) Triptorelin 52/1,517 (3.4%) 6 3 2 5/8 (62.5%) Degarelix 82/2,787 (2.9%) 7 4 3 10/11 (90.9%) Bicalutamide 724/10,144 (7.1%) 23 16 11 28/41 (68.3%) Flutamide 163/4075 (4%) 4 2 3 3/7 (42.9%) Enzalutamide 5,430/31,896 (17%) 19 4 13 30/32 (93.8%) Abiraterone 1,240/14,261 (8.7%) 19 7 10 29/31 (92.5%) Finasteride 1,062/33,877 (3.1%) 52 20 32 20/87 (23%) Dutasteride 248/15,177 (1.6%) 26 7 11 5/38 (13.2%) Total ADT* 10,540/127,385 (8.3%) 168 68 99 137/283 (48.4%) Number (n) of case reports in men in the WHO international pharmacovigilance database (VigiBase) by ADT through 08/09/2018. *Some patients were on combination ADT.

Enzalutamide electrophysiology IPS-CMs

Conclusion

ADT is a risk factor for aLQT and TdP. Androgens may be useful in TdP treatment of hypogonadic men.

Acknowledgement/Funding

INSERM

Determinants of hydroxychloroquine blood concentration variations in systemic lupus erythematosus

OBJECTIVE

Blood concentrations of hydroxychloroquine (HCQ) vary widely among patients with systemic lupus erythematosus (SLE). A pharmacokinetic/pharmacodynamic relationship has been found in different situations, and a very low blood concentration of HCQ is a simple marker of nonadherence to treatment. Therefore, interest in blood HCQ concentration measurement has increased, but little is known about factors that influence blood HCQ concentration variability. This study was undertaken to analyze determinants of blood HCQ concentrations.

METHODS

We conducted a retrospective analysis of patient data, including data from the Plaquenil Lupus Systemic (PLUS) study, to determine the association of epidemiologic, clinical, and biologic factors with blood HCQ concentrations. Data for nonadherent patients (blood HCQ concentration <200 ng/ml) were excluded.

RESULTS

To examine homogeneous pharmacologic data, we restricted the analyses of the PLUS data to the 509 SLE patients receiving 400 mg/day. We found no association of ethnicity or smoking with blood HCQ concentrations and no pharmacokinetic drug-drug interaction with antacids or with inhibitors or inducers of cytochrome P450 enzymes. On multivariate analysis, high body mass index (P = 0.008), no treatment with corticosteroids (P = 0.04), increased time between the last tablet intake and measurement of blood HCQ concentrations (P = 0.017), low platelet count (P < 0.001), low neutrophil count (P < 0.001), and high estimated creatinine clearance (P < 0.001) were associated with low blood HCQ concentrations. In 22 SLE patients with chronic renal insufficiency (median serum creatinine clearance 52 ml/minute [range 23-58 ml/minute]) who received 400 mg/day HCQ, the median blood HCQ concentration was significantly higher than that in the 509 patients from the PLUS study (1,338 ng/ml [range 504-2,229 ng/ml] versus 917 ng/ml [range 208-3316 ng/ml]) (P < 0.001).

CONCLUSION

We provide a comprehensive analysis of determinants of blood HCQ concentrations. Because this measurement is increasingly being used, these data might be useful for clinicians.

Effectiveness of gene delivery systems for pluripotent and differentiated cells

Human embryonic stem cells (hESC) and induced pluripotent stem cells (hiPSC) assert a great future for the cardiovascular diseases, both to study them and to explore therapies. However, a comprehensive assessment of the viral vectors used to modify these cells is lacking. In this study, we aimed to compare the transduction efficiency of recombinant adeno-associated vectors (AAV), adenoviruses and lentiviral vectors in hESC, hiPSC, and the derived cardiomyocytes. In undifferentiated cells, adenoviral and lentiviral vectors were superior, whereas in differentiated cells AAV surpassed at least lentiviral vectors. We also tested four AAV serotypes, 1, 2, 6, and 9, of which 2 and 6 were superior in their transduction efficiency. Interestingly, we observed that AAVs severely diminished the viability of undifferentiated cells, an effect mediated by induction of cell cycle arrest genes and apoptosis. Furthermore, we show that the transduction efficiency of the different viral vectors correlates with the abundance of their respective receptors. Finally, adenoviral delivery of the calcium-transporting ATPase SERCA2a to hESC and hiPSC-derived cardiomyocytes successfully resulted in faster calcium reuptake. In conclusion, adenoviral vectors prove to be efficient for both differentiated and undifferentiated lines, whereas lentiviral vectors are more applicable to undifferentiated cells and AAVs to differentiated cells.

Reduced-function CYP2C19 genotype and risk of adverse clinical outcomes among patients treated with clopidogrel predominantly for PCI: a meta-analysis

CONTENT

Clopidogrel, one of the most commonly prescribed medications, is a prodrug requiring CYP450 biotransformation. Data suggest its pharmacologic effect varies based on CYP2C19 genotype, but there is uncertainty regarding the clinical risk imparted by specific genotypes.

OBJECTIVE

To define the risk of major adverse cardiovascular outcomes among carriers of 1 (≈ 26% prevalence in whites) and carriers of 2 (≈ 2% prevalence in whites) reduced-function CYP2C19 genetic variants in patients treated with clopidogrel.

DATA SOURCES AND STUDY SELECTION

A literature search was conducted (January 2000-August 2010) in MEDLINE, Cochrane Database of Systematic Reviews, and EMBASE. Genetic studies were included in which clopidogrel was initiated in predominantly invasively managed patients in a manner consistent with the current guideline recommendations and in which clinical outcomes were ascertained.

DATA EXTRACTION

Investigators from 9 studies evaluating CYP2C19 genotype and clinical outcomes in patients treated with clopidogrel contributed the relevant hazard ratios (HRs) and 95% confidence intervals (CIs) for specific cardiovascular outcomes by genotype.

RESULTS

Among 9685 patients (91.3% who underwent percutaneous coronary intervention and 54.5% who had an acute coronary syndrome), 863 experienced the composite end point of cardiovascular death, myocardial infarction, or stroke; and 84 patients had stent thrombosis among the 5894 evaluated for such. Overall, 71.5% were noncarriers, 26.3% had 1 reduced-function CYP2C19 allele, and 2.2% had 2 reduced-function CYP2C19 alleles. A significantly increased risk of the composite end point was evident in both carriers of 1 (HR, 1.55; 95% CI, 1.11-2.17; P = .01) and 2 (HR, 1.76; 95% CI, 1.24-2.50; P = .002) reduced-function CYP2C19 alleles, as compared with noncarriers. Similarly, there was a significantly increased risk of stent thrombosis in both carriers of 1 (HR, 2.67; 95% CI, 1.69-4.22; P < .0001) and 2 (HR, 3.97; 95% CI, 1.75-9.02; P = .001) CYP2C19 reduced-function alleles, as compared with noncarriers.

CONCLUSION

Among patients treated with clopidogrel for percutaneous coronary intervention, carriage of even 1 reduced-function CYP2C19 allele appears to be associated with a significantly increased risk of major adverse cardiovascular events, particularly stent thrombosis.

Favorable outcome of IgA nephropathy on antituberculous treatment

We report the case of an association of IgA nephropathy and tuberculosis with superimposed vasculitis lesions on the renal biopsy. Three previous cases of the same association are discussed. The nephropathy had a favorable course in all of these cases on antituberculous treatment only. Tuberculosis is another infection related to IgA nephropathy.

[Arrhythmogenic right ventricular dysplasia and sudden cardiac death]

ARVD manifests itself by a wide spectrum of clinical presentations from asymptomatic patients to a broad range of ventricular arrhythmia, extrasystoles, tachycardia, or sudden arrhythmic death which can be the first symptom. It is a major cause for sudden death in young people and sportsmen. In known ARVD the risk of sudden death is not easy to assess from the literature, as its natural history is modulated by the wide variety of antiarrhythmic therapies. Hemodynamically ill tolerated ventricular arrhythmia, left ventricular involvement, sports, a youger age below 35, and uncontrolled therapy seem to predict an adverse outcome for these patients. These data may be helpful to decide for an AICD.

Beta-blocker treatment in heart failure

Heart failure treatment has markedly changed during the last few decades, with demonstration of benefit of afterload reduction by vasodilator therapy and introduction of the concept of the deleterious consequences of the neuro-hormonal compensatory stimulation. Blockade of beta-adrenergic receptors, initially contra-indicated in heart failure, provide a marked reduction of mortality and morbidity in combination with diuretics and angiotensin-converting enzyme inhibitors, as demonstrated in many clinical trials. We performed a review of all clinical trials that compare beta-blockers vs. placebo in chronic heart failure. Beta-blockers with different pharmacological profiles have been tested, mainly metoprolol, bisoprolol, bucindolol and carvedilol. With progressive dose increment, tolerance of such treatment was generally good, left ventricular function improved, hospitalisations for heart failure were less frequent and mortality was reduced. The meta-analysis of the 16 randomised trials, with at least one death in each treatment group, provides a 24% relative risk reduction for such hospitalisations (95% CI=19%-29%) and 22% reduction for mortality (95% CI=16%-28%). Heterogeneity of beta-blocker effect for mortality was found and related to the non-significant benefit obtained in the BEST trial with bucindolol. When such a trial is excluded, the effect model analysis shows that relative risk reduction (beta-blocker induced benefit) is constant whatever the severity of the disease. The mechanism of beta-blocker induced benefit remains unclear, but is at least partly related to left ventricular function improvement and prevention of severe ventricular arrhythmias. In conclusion, beta-blocker treatment has become an established therapy for heart failure, in combination with diuretics and ACE inhibitors. Complementary informations will be needed to clarify the mechanism of benefit and to define the best therapeutic strategy according to the individual characteristics of patients with heart failure.

Heart rate and cardiac rhythm relationships with bisoprolol benefit in chronic heart failure in CIBIS II Trial

BACKGROUND

beta-Blockade-induced benefit in heart failure (HF) could be related to baseline heart rate and treatment-induced heart rate reduction, but no such relationships have been demonstrated.

METHODS AND RESULTS

In CIBIS II, we studied the relationships between baseline heart rate (BHR), heart rate changes at 2 months (HRC), nature of cardiac rhythm (sinus rhythm or atrial fibrillation), and outcomes (mortality and hospitalization for HF). Multivariate analysis of CIBIS II showed that in addition to beta-blocker treatment, BHR and HRC were both significantly related to survival and hospitalization for worsening HF, the lowest BHR and the greatest HRC being associated with best survival and reduction of hospital admissions. No interaction between the 3 variables was observed, meaning that on one hand, HRC-related improvement in survival was similar at all levels of BHR, and on the other hand, bisoprolol-induced benefit over placebo for survival was observed to a similar extent at any level of both BHR and HRC. Bisoprolol reduced mortality in patients with sinus rhythm (relative risk 0.58, P:<0.001) but not in patients with atrial fibrillation (relative risk 1.16, P:=NS). A similar result was observed for cardiovascular mortality and hospitalization for HF worsening.

CONCLUSIONS

BHR and HRC are significantly related to prognosis in heart failure. beta-Blockade with bisoprolol further improves survival at any level of BHR and HRC and to a similar extent. The benefit of bisoprolol is questionable, however, in patients with atrial fibrillation.

Feasibility and safety of ultrasound-aided thoracentesis in mechanically ventilated patients

OBJECTIVE

Thoracentesis in a ventilated patient is rarely performed because of the risk of pneumothorax. We have evaluated the safety of this procedure when aided by ultrasound.

DESIGN

Prospective study.

SETTING

Medical intensive care unit, university-affiliated hospital.

PATIENTS

45 procedures were performed in 40 consecutive patients with ultrasound signs of pleural effusion, all mechanically ventilated.

INTERVENTIONS

Pleural effusion was defined on ultrasound as a collection of fluid between parietal and visceral pleura leading to variations in interpleural distance during breathing. When the interpleural distance was >/= 15 mm and visible over three intercostal spaces, a needle (16 or 21 G) was inserted after ultrasound localization in a patient in either dorsal or lateral decubitus.

RESULTS

No complication occurred in the 45 thoracenteses. Fluid was obtained in 44 of 45 procedures, thus confirming the diagnosis of pleural effusion. The procedure was immediate (less than 10 s) in 40 of 45 cases. It was easy (i. e., keeping the patient supine) in 22 of 45 procedures. In 44 cases where fluid was obtained, only 27 bedside radiographs revealed signs of effusion, whereas 17 showed absence of a visible effusion. Ultrasound thus appeared more efficient than bedside X-ray in detecting pleural effusion.

CONCLUSIONS

If basic rules are followed, ultrasound localization makes thoracentesis a safe, easy and simple procedure in patients on mechanical ventilation.