Sympathetic and Vagal Nerve Activity in COPD: Pathophysiology, Presumed Determinants and Underappreciated Therapeutic Potential

This article explains the comprehensive state of the art assessment of sympathetic (SNA) and vagal nerve activity recordings in humans and highlights the precise mechanisms mediating increased SNA and its corresponding presumed clinical determinants and therapeutic potential in the context of chronic obstructive pulmonary disease (COPD). It is known that patients with COPD exhibit increased muscle sympathetic nerve activity (MSNA), as measured directly using intraneural microelectrodes—the gold standard for evaluation of sympathetic outflow. However, the underlying physiological mechanisms responsible for the sympathoexcitation in COPD and its clinical relevance are less well understood. This may be related to the absence of a systematic approach to measure the increase in sympathetic activity and the lack of a comprehensive approach to assess the underlying mechanisms by which MSNA increases. The nature of sympathoexcitation can be dissected by distinguishing the heart rate increasing properties (heart rate and blood pressure variability) from the vasoconstrictive drive to the peripheral vasculature (measurement of catecholamines and MSNA) (Graphical Abstract Figure 1). Invasive assessment of MSNA to the point of single unit recordings with analysis of single postganglionic sympathetic firing, and hence SNA drive to the peripheral vasculature, is the gold standard for quantification of SNA in humans but is only available in a few centres worldwide because it is costly, time consuming and requires a high level of training. A broad picture of the underlying pathophysiological determinants of the increase in sympathetic outflow in COPD can only be determined if a combination of these tools are used. Various factors potentially determine SNA in COPD (Graphical Abstract Figure 1): Obstructive sleep apnoea (OSA) is highly prevalent in COPD, and leads to repeated bouts of upper airway obstructions with hypoxemia, causing repetitive arousals. This probably produces ongoing sympathoexcitation in the awake state, likely in the “blue bloater” phenotype, resulting in persistent vasoconstriction. Other variables likely describe a subset of COPD patients with increase of sympathetic drive to the heart, clinically likely in the “pink puffer” phenotype. Pharmacological treatment options of increased SNA in COPD could comprise beta blocker therapy. However, as opposed to systolic heart failure a similar beneficial effect of beta blocker therapy in COPD patients has not been shown. The point is made that although MSNA is undoubtedly increased in COPD (probably independently from concomitant cardiovascular disease), studies designed to determine clinical improvements during specific treatment will only be successful if they include adequate patient selection and translational state of the art assessment of SNA. This would ideally include intraneural recordings of MSNA and—as a future perspective—vagal nerve activity all of which should ideally be assessed both in the upright and in the supine position to also determine baroreflex function.

Transmural voltage gradient dispersion and heterogeneity in brugada syndrome phenotype - a novel workflow for advanced mapping using endocardial unipolar electrograms J-point elevation

Funding Acknowledgements

Type of funding sources: None.

Background

Differential action potential duration shortening across the right ventricular (RV) myocardial wall is primarily responsible for the Brugada Syndrome (BrS) phenotype [1]. To date, data on electrical substrate characterization in humans with BrS phenotype is limited and risk evaluation is still controversial.

Purpose

We hypothesized that Uni-JEl mapping could be used as a marker of transmural voltage gradient dispersion resulting. Our aim was to evaluate Uni-JEl mapping in defining arrhythmogenic substrates in patients with BrS phenotype.

Methods

12 patients were included in our analysis. 2 normal patients provided control data and 10 asymptomatic subjects with spontaneous type-1 BrS underwent 3D RV mapping (CARTO3 System, Biosense Webster). Among BrS patients we had 3 patients with arrhythmic events (aborted sudden death or appropriate ICD therapies) during follow-up (median 56, interquartile range: 46-74 months) and 7 patients without arrhythmic events. In the former group we had 1 patient with inducibility of VT/VF during EPS (EPS+) and 2 patients non-inducibles during EPS (EPS-), in the latter group we had 3 patients with EPS+ and 4 patients with EPS-. Electrophysiological data and signals were exported and OpenEP [2] was used to convert Carto proprietary data formats into Matlab format (Fig.1). Uni-JEl was calculated for each point map as the unipolar value at J point on surface electrocardiogram. Uni-JEl values were then interpolated in Paraview to create Uni-JEl maps, interpolating data points on the mesh cell (Fig.1). Finally, a region of interest (ROI) was selected and the calculation of mean Uni-JEI (MUni-JEI, as a measure of voltage gradient dispersion), interquartile range and range (intrqUni-JEI and ∆Uni-JEI, as markers of heterogeneity of dispersion) was performed. Results are shown as mean ± standard deviation for the group of BrS patients and the actual values for the two controls.

Results

BrS patients showed Muni-JEl, intrqUni-JEl and ∆Uni-JEI higher than controls (2.03 mV ± 0.31 mV vs 0,82 mV and 1,1 mV, 1.90 mV ± 0.82 mV vs 1,04 mV and 1,18 mV 6.26 mV ± 1.98 mV vs 3,54 mV and 4,01 mV, respectively). BrS patients with arrhythmic events during the follow-up showed higher intrqUni-JEl and the ∆Uni-JEI respect to BrS with EPS+ and without arrhythmic events during follow-up (2.31 mV ± 0.44 mV vs 0.78 mV ± 0.11 mV and 6.69 mV ± 2.27 mV vs 3.98 mV ± 0.31 mV). Figure 2 shows some examples of calculated Uni-JEl maps for each group under study.

Conclusions

In this work we introduced a novel workflow for the electrical substrate characterization of subjects with BrS phenotype. The results from our preliminary analysis indicate that a higher transmural voltage gradient dispersion and heterogeneity can be found in type-1 BrS with respect to normal subjects. Voltage gradient dispersion heterogeneity could be used to better recognize high risk BrS patients regardless of VT/VF inducibility during EPS.

C42 MULTI–CHAMBER SPECKLE TRACKING IMAGING AND DIAGNOSTIC VALUE OF LEFT ATRIAL STRAIN IN CARDIAC AMYLOIDOSIS

Background

Amyloid deposits in all cardiac chambers, impairing their function. We investigated for the first time if a speckle–tracking echocardiography (STE) analysis extended to all 4 chambers might hold additive diagnostic value for CA and its subtypes (amyloid transthyretin [ATTR–] and light–chain [AL]–CA).

Methods

We evaluated 423 consecutive patients undergoing a diagnostic workup for CA in 2 referral centres from 2015 to 2020.

Results

CA was diagnosed in 261 patients (62%; ATTR–CA, n = 144, 34%; AL–CA, n = 117, 28%). Patients with CA had an impaired function of all cardiac chambers, particularly those with ATTR–CA. Peak left atrial longitudinal strain (LA–PALS) was the only STE parameter that predicted CA and ATTR–CA independent of laboratory and standard echocardiographic variables (Model 1). It also predicted ATTR–CA among patients with unexplained hypertrophy regardless of a diagnostic score (IWT score). Patients with either LA–PALS or LA–peak atrial contraction strain (PACS) in the first quartile (LA–PALS <6.65% or LA–PACS <3.62%) had an almost 4–fold higher likelihood of CA and ATTR–CA regardless of Model 1. Among patients with unexplained hypertrophy, those with LA–PALS or LA–PACS in the first quartile had an almost 9–fold higher likelihood of ATTR–CA irrespective of Model 1, and a 2–fold higher likelihood of ATTR–CA beyond the IWT score.

Conclusions

STE measures of all 4 chambers are abnormal in patients with CA, particularly in those with ATTR–CA. LA strain holds independent diagnostic significance. Among patients screened for CA, those with LA–PALS <6.65% and/or LA–PACS <3.62% have a high likelihood of CA and ATTR–CA.

C63 PHENOTYPE – GENOTYPE RELATIONSHIP IN ARRHYTHMOGENIC CARDIOMYOPATHY

Background

Arrhythmogenic cardiomyopathy (ACM) is a primary disease of the myocardium with arrhythmic manifestations and fibro–fatty replacement either of the right (RV) or the left ventricle (LV) at the cardiac magnetic resonance (CMR). Over the last decade, different mutations in cardiac genes associated with heterogeneous phenotypes have been identified.

Aim

To investigate the genotype–phenotype relationships in ACM patients. Firstly, the phenotypic expression was defined in definite mutation carriers. Secondly, the prognostic significance of mutations was assessed across different phenotypes.

Methods

The study population included 281 patients with suspected ACM, based on family history, clinical and electrocardiographic evaluation, echocardiographic and CMR findings (Fig.1), studied at our Institution since 2012. All patients underwent genetic evaluation using Sanger sequencing and NGS of mutations in desmosomal (desmoplakin [DSP], plakophilin–2[PKP2], plakoglobin[JUP], desmoglein–2 [DSG2], desmocollin–2 [DSC2]) or non desmosomal genes. The composite endpoint included cardiac death, sustained and non–sustained ventricular tachycardia (VT), ventricular fibrillation (VF), appropriate defibrillator shock/antitachycardia pacing (ATP).

Results

The genetic test was positive in 113 patients (40%), 82 (73%) for desmosomal genes (41 DSP, 15 DSG2, 15 PKP2, 5 JUP, 6 DSC2), and 31 (27%) for non–desmosomal genes (4 titin, 2 TMEM 43, 2 lamin A/C, 23 others). Gene–positive compared to gene–negative (n = 168, 60%) patients showed a higher prevalence of LV ejection fraction (EF)<50% (14%vs.6%, p<0.011), LV and RV LGE (62%vs.46%, p < 0.001, 20%vs.12%, p<0.02), RV dilatation (27%vs.17%, p<0.041) (Table 1). DSG2 mutations were associated mainly to biventricular (7/15,46%) or RV involvement (4/15,26%), while DSP mutations to LV involvement (24/41,58%). During a median 36–month follow–up (IQ.range 12–56), 55 patients (19%) experienced the composite endpoint (35 non–sustained VT; 11 sustained VT – 3 ATP, 1 defibrillator–shock–; 9 VF, all treated by defibrillator–shock). At Kaplan–Meier analysis, DSP mutations were associated with the worst prognosis (Fig. 3). Conclusion Diverse genotypes were differently associated with LV dysfunction/LGE, RV dilatation/LGE. DSP mutations were associated with higher arrhythmic risk. Genetic screening may result in a better risk stratification, useful for clinical decision–making.

P294 AN ECHOCARDIOGRAPHIC SCORE OF VALVE DISEASE IN PATIENTS WITH CARDIAC AMYLOIDOSIS

Background

Cardiac amyloidosis (CA) affects all cardiac structures, including the valves. We summarized the echocardiographic features of valve disease in a score.

Methods

From 423 patients undergoing a diagnostic workup for CA we selected 2 samples of 20 patients with amyloid transthyretin (ATTR–) or light–chain (AL–) CA, and selected age– and sex–matched controls. The Amyloid VAlve (AVA) score included 31 items related to the mitral, aortic and tricuspid valves (which can be properly assessed in standard echocardiograms), with a value of 1 for each abnormal item.

Results

Patients with ATTR–CA displayed more often a shortened/hidden and retracted posterior mitral valve leaflet (PMVL), thickened mitral chordae tendineae and aortic stenosis than those with AL–CA, and less frequent PMVL calcification than matched controls. Score values were 15.8 (interquartile interval 13.6–17.4) in ATTR–CA, 11.0 (9.3–14.9) in AL–CA, 12.8 (11.1–14.4) in ATTR–CA controls, and 11.0 (9.1–13.0) in AL–CA controls (p = 0.004 for ATTR– vs. AL–CA, 0.009 for ATTR–CA vs. their controls, and 0.461 for AL–CA vs. controls). We compared the AVA and two validated diagnostic scores (IWT and AMYLI). AUC values for the diagnosis of ATTR–CA were 0.782, 0.846 and 0.902, respectively, in patients with ATTR–CA or matched controls, and 0.773, 0.706 and 0.679 in patients with LV hypertrophy (n = 67, 84%) (all non–significant p values).

Conclusions

Patients with ATTR–CA have a prominent impairment of mitral valve structure and function, and higher score values. The AVA score is quite effective in identifying patients with ATTR–CA among patients with CA or with unexplained hypertrophy.

Circulating levels and prognostic cut-offs of sST2, hs-cTnT, and NT-proBNP in women vs. men with chronic heart failure

Aims

To define plasma concentrations, determinants, and optimal prognostic cut‐offs of soluble suppression of tumorigenesis‐2 (sST2), high‐sensitivity cardiac troponin T (hs‐cTnT), and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) in women and men with chronic heart failure (HF).

Methods and results

Individual data of patients from the Biomarkers In Heart Failure Outpatient Study (BIOS) Consortium with sST2, hs‐cTnT, and NT‐proBNP measured were analysed. The primary endpoint was a composite of 1 year cardiovascular death and HF hospitalization. The secondary endpoints were 5 year cardiovascular and all‐cause death. The cohort included 4540 patients (age 67 ± 12 years, left ventricular ejection fraction 33 ± 13%, 1111 women, 25%). Women showed lower sST2 (24 vs. 27 ng/mL, P < 0.001) and hs‐cTnT level (15 vs. 20 ng/L, P < 0.001), and similar concentrations of NT‐proBNP (1540 vs. 1505 ng/L, P = 0.408). Although the three biomarkers were confirmed as independent predictors of outcome in both sexes, the optimal prognostic cut‐off was lower in women for sST2 (28 vs. 31 ng/mL) and hs‐cTnT (22 vs. 25 ng/L), while NT‐proBNP cut‐off was higher in women (2339 ng/L vs. 2145 ng/L). The use of sex‐specific cut‐offs improved risk prediction compared with the use of previously standardized prognostic cut‐offs and allowed to reclassify the risk of many patients, to a greater extent in women than men, and for hs‐cTnT than sST2 or NT‐proBNP. Specifically, up to 18% men and up to 57% women were reclassified, by using the sex‐specific cut‐off of hs‐cTnT for the endpoint of 5 year cardiovascular death.

Conclusions

In patients with chronic HF, concentrations of sST2 and hs‐cTnT, but not of NT‐proBNP, are lower in women. Lower sST2 and hs‐cTnT and higher NT‐proBNP cut‐offs for risk stratification could be used in women.

In Vivo Murine Models of Cardiotoxicity Due to Anticancer Drugs: Challenges and Opportunities for Clinical Translation

Modern therapeutic approaches have led to an improvement in the chances of surviving a diagnosis of cancer. However, this may come with side effects, with patients experiencing adverse cardiovascular events or exacerbation of underlying cardiovascular disease related to their cancer treatment. Rodent models of chemotherapy-induced cardiotoxicity are useful to define pathophysiological mechanisms of cardiac damage and to identify potential therapeutic targets. The key mechanisms involved in cardiotoxicity induced by specific different antineoplastic agents are summarized in this state-of-the-art review, as well as the rodent models of cardiotoxicity by different classes of anticancer drugs, along with the strategies tested for primary and secondary cardioprotection. Current approaches for early detection of cardiotoxicity in preclinical studies with a focus on the application of advanced imaging modalities and biomarker strategies are also discussed. Potential applications of cardiotoxicity modelling in rodents are illustrated in relation to the advancements of promising research topics of cardiotoxicity. Created with BioRender.com.

Central Apneas Are More Detrimental in Female Than in Male Patients With Heart Failure

Background

Central apneas (CA) are a frequent comorbidity in patients with heart failure (HF) and are associated with worse prognosis. The clinical and prognostic relevance of CA in each sex is unknown.

Methods and Results

Consecutive outpatients with HF with either reduced or mildly reduced left ventricular ejection fraction (n=550, age 65±12 years, left ventricular ejection fraction 32%±9%, 21% women) underwent a 24‐hour ambulatory polygraphy to evaluate CA burden and were followed up for the composite end point of cardiac death, appropriate implantable cardioverter‐defibrillator shock, or first HF hospitalization. Compared with men, women were younger, had higher left ventricular ejection fraction, had lower prevalence of ischemic etiology and of atrial fibrillation, and showed lower apnea‐hypopnea index (expressed as median [interquartile range]) at daytime (3 [0–9] versus 10 [3–20] events/hour) and nighttime (10 [3–21] versus 23 [11–36] events/hour) (all P<0.001), despite similar neurohormonal activation and HF therapy. Increased chemoreflex sensitivity to either hypoxia or hypercapnia (evaluated in 356 patients, 65%, by a rebreathing test) was less frequent in women (P<0.001), but chemoreflex sensitivity to hypercapnia was a predictor of apnea‐hypopnea index in both sexes. At adjusted survival analysis, daytime apnea‐hypopnea index ≥15 events/hour (hazard ratio [HR], 2.70; 95% CI, 1.06–7.34; P=0.037), nighttime apnea‐hypopnea index ≥15 events/hour (HR, 2.84; 95% CI, 1.28–6.32; P=0.010), and nighttime CA index ≥10 events/hour (HR, 5.01; 95% CI, 1.88–13.4; P=0.001) were independent predictors of the primary end point in women but not in men (all P>0.05), also after matching women and men for possible confounders.

Conclusions

In chronic HF, CA are associated with a greater risk of adverse events in women than in men.

Inferior Vena Cava Edge Tracking Echocardiography: A Promising Tool with Applications in Multiple Clinical Settings

Ultrasound (US)-based measurements of the inferior vena cava (IVC) diameter are widely used to estimate right atrial pressure (RAP) in a variety of clinical settings. However, the correlation with invasively measured RAP along with the reproducibility of US-based IVC measurements is modest at best. In the present manuscript, we discuss the limitations of the current technique to estimate RAP through IVC US assessment and present a new promising tool developed by our research group, the automated IVC edge-to-edge tracking system, which has the potential to improve RAP assessment by transforming the current categorical classification (low, normal, high RAP) in a continuous and precise RAP estimation technique. Finally, we critically evaluate all the clinical settings in which this new tool could improve current practice.

Assessment of Phasic Changes of Vascular Size by Automated Edge Tracking-State of the Art and Clinical Perspectives

Assessment of vascular size and of its phasic changes by ultrasound is important for the management of many clinical conditions. For example, a dilated and stiff inferior vena cava reflects increased intravascular volume and identifies patients with heart failure at greater risk of an early death. However, lack of standardization and sub-optimal intra- and inter- operator reproducibility limit the use of these techniques. To overcome these limitations, we developed two image-processing algorithms that quantify phasic vascular deformation by tracking wall movements, either in long or in short axis. Prospective studies will verify the clinical applicability and utility of these methods in different settings, vessels and medical conditions.

Sacubitril/valsartan reduces indications for arrhythmic primary prevention in heart failure with reduced ejection fraction: insights from DISCOVER-ARNI, a multicenter Italian register

Aims

This sub-study deriving from a multicentre Italian register [Deformation Imaging by Strain in Chronic Heart Failure Over Sacubitril-Valsartan: A Multicenter Echocardiographic Registry (DISCOVER)-ARNI] investigated whether sacubitril/valsartan in addition to optimal medical therapy (OMT) could reduce the rate of implantable cardioverter-defibrillator (ICD) indications for primary prevention in heart failure with reduced ejection fraction (HFrEF) according to European guidelines indications, and its potential predictors.

Methods and results

In this observational study, consecutive patients with HFrEF eligible for sacubitril/valsartan from 13 Italian centres were included. Lack of follow-up or speckle tracking data represented exclusion criteria. Demographic, clinical, biochemical, and echocardiographic data were collected at baseline and after 6 months from sacubitril/valsartan initiation. Of 351 patients, 225 (64%) were ICD carriers and 126 (36%) were not ICD carriers (of whom 13 had no indication) at baseline. After 6 months of sacubitril/valsartan, among 113 non-ICD carriers despite having baseline left ventricular (LV) ejection fraction (EF) ≤ 35% and New York Heart Association (NYHA) class = II-III, 69 (60%) did not show ICD indications; 44 (40%) still fulfilled ICD criteria. Age, atrial fibrillation, mitral regurgitation > moderate, left atrial volume index (LAVi), and LV global longitudinal strain (GLS) significantly varied between the groups. With receiver operating characteristic curves, age ≥ 75 years, LAVi ≥ 42 mL/m2 and LV GLS ≥-8.3% were associated with ICD indications persistence (area under the curve = 0.65, 0.68, 0.68, respectively). With univariate and multivariate analysis, only LV GLS emerged as significant predictor of ICD indications at follow-up in different predictive models.

Conclusions

Sacubitril/valsartan may provide early improvement of NYHA class and LVEF, reducing the possible number of implanted ICD for primary prevention in HFrEF. Baseline reduced LV GLS was a strong marker of ICD indication despite OMT. Early therapy with sacubitril/valsartan may save infective/haemorrhagic risks and unnecessary costs deriving from ICDs.

297 Echocardiographic biventricular coupling index to predict pre-capillary pulmonary hypertension

Aims

Pulmonary hypertension (PH) affects millions of people worldwide. Right heart catheterization (RHC) is the gold standard to correctly classify the subtype of PH. Biventricular coupling index (BCI) is a new echocardiographic index defined as the ratio between non-invasive right ventricular stroke work index (RVSWI) and E/E′ ratio. Due to his comprehensive functional characterization of the right heart physiology, we hypothesized it might correctly identify pre-capillary PH.

Methods and results

BCI was derived in a cohort of 334 patients from the University Hospital of Trieste (Italy) and Karolinska University Hospital (Sweden) who underwent transthoracic echocardiography and RHC for all indications (&lt;6 h between the exams). The accuracy of BCI to identify pre-capillary PH was high in the derivation cohort (AUC: 0.82, P &lt; 0.001, CI: 0.78–0.88). Subsequently BCI was tested in a large validation cohort of 1349 patients with available transthoracic echocardiography and RHC from the Fondazione Toscana G. Monasterio of Pisa (Italy). Among patients with PH, BCI showed a high accuracy to correctly identify pre-capillary PH (AUC = 0.91, 95% CI: 0.89–0.93, P &lt; 0.001), with an optimal cut-off of 1.9 providing a sensitivity of 82% and a specificity of 89%, PPV 77%, and a NPV 92%. BCI outperformed previous indexes, such as the D’Alto score (Z coefficient 3.56, difference between areas 0.05 95% CI: 0.02–0.07, P &lt; 0.001) and the echocardiographic Pulmonary to Left Atrial Ratio (ePLAR) index (Z coefficient 2.88, difference between areas 0.02 95% CI: 0.01–0.04, P &lt; 0.004).

Conclusions

BCI is a new non-invasive index based on standard echocardiographic parameters that allows, with high accuracy, the identification of patients with pre-capillary PH, outperforming previously proposed indexes. Routine use of BCI index could be implemented in the screening work-up of pre-capillary PH.

266 Deformation imaging by strain in chronic heart failure over sacubitril–valsartan: a multicentre echocardiographic registry (discover)—ARNI

Aims

Sacubitril/valsartan have changed the treatment of heart failure with reduced ejection fraction (HFrEF), due to the positive effects morbidity and mortality partly mediated by left ventricular reverse remodelling (LVRR). The aim of this multicentre study was to identify echocardiographic predictors of LVRR after sacubitril/valsartan administration.

Methods and results

Patients with HFrEF requiring therapy with sacubitril/valsartan from 13 Italian centres were included. Echocardiographic indexes including speckle tracking echocardiography (STE) indexes were used to predict LVRR [defined as LV end-systolic volume reduction and ejection fraction (LVEF) improvement &gt; 10% at follow-up] at 6 months follow-up as the primary endpoint. Changes in symptoms (NYHA class) and neurohormonal activations [N-terminal-pro-brain natriuretic peptide (NTproBNP)] were also evaluated as secondary endpoints. The final population (excluding patients with poor acoustic windows and missing data) consists of 341 patients [mean age: 65 ± 10 years; 18% female, median LVEF 30% (interquartile range: 25–34)]. At 6 months follow-up, 82 (24%) patients showed early complete response (LVRR and LVEF ≥35%), 55 (16%) early incomplete response (LVRR and LVEF &lt;35%), 204 (60%) no response (no LVRR and LVEF &lt;35%). Non-ischaemic etiology, a lower left atrial volume index and a higher global longitudinal strain were all independent predictors of LVRR at multivariable logistic analysis (all P &lt; 0.01). LA strain was the best predictor of positive changes in NYHA class and NT-proBNP (all P &lt; 0.05) (Figure 1).

Conclusions

STE parameters at baseline could be useful to predict LVRR and clinical response to sacubitril-valsartan, and thus could be used as a guide for treatment in patients with HFrEF.

279 Medical treatment with ARNI may reduce indications for primary prevention of sudden cardiac death in heart failure with reduced ejection fraction: insights from discover-ARNI, a multicentre Italian register

Aims

This sub-study deriving from a multicentre Italian register (DISCOVER-ARNI) investigated whether sacubitril/valsartan in adjunction of optimal medical therapy (OMT) could reduce the rate of implantable cardioverter-defibrillator(ICD) indications for primary prevention in heart failure with reduced ejection fraction (HFrEF) according to European guidelines indications, and its potential predictors.

Methods and results

In this observational study, consecutive patients with HFrEF eligible for sacubitril/valsartan from 13 Italian centres were included. Lack of follow-up or speckle tracking data represented exclusion criteria. Demographic, clinical, biochemical and echocardiographic data were collected at baseline and after 6 months of therapy. Of 351 patients, 225 (64%) were ICD carriers and 126 (36%) were not ICD carriers (of whom 13 had not indication) at baseline. After 6 months of sacubitril/valsartan, among 113 non-ICD carriers despite having baseline left ventricular (LV)EF ≤ 35% and New York Heart Association (NYHA) class = II–III, 69(60%) did not show ICD indications; 44(40%) still fulfilled ICD criteria (Figure 1). Age, atrial fibrillation, mitral regurgitation&gt;moderate, left atrial volume index (LAVi), and LV global longitudinal strain (GLS) significantly varied between the groups. With ROC curves, age ≥ 75 years, LAVi ≥ 42 ml/m2 and LV GLS ≥ −8.3% were associated with ICD indications persistence (AUC = 0.65, 0.68, and 0.68, respectively). With univariate and multivariate analysis, age and LV GLS emerged as the only significant predictors of ICD indications at follow-up.

Conclusions

Sacubitril/valsartan provided early improvement of NYHA class and LVEF, reducing the possible number of implanted ICD for primary prevention in HFrEF. Baseline advanced age and reduced LV GLS were markers of ICD indication despite OMT. Early therapy with sacubitril/valsartan may save infective/haemorrhagic risks and unnecessary costs deriving from ICDs.

417 Multi-chamber speckle tracking imaging and diagnostic value of left atrial strain in cardiac amyloidosis

Aims

Amyloid deposits in all cardiac chambers, impairing their function. We investigated for the first time if a speckle-tracking echocardiography (STE) analysis extended to all four chambers might hold additive diagnostic value for CA and its subtypes [amyloid transthyretin (ATTR-) and light-chain (AL)-CA].

Methods and results

We evaluated 423 consecutive patients undergoing a diagnostic workup for CA in two referral centres from 2015 to 2020. CA was diagnosed in 261 patients (62%; ATTR-CA, n = 144, 34%; AL-CA, n = 117, 28%). Patients with CA had an impaired function of all cardiac chambers, particularly those with ATTR-CA. Peak left atrial longitudinal strain (LA-PALS) was the only STE parameter that predicted CA and ATTR-CA independent of laboratory and standard echocardiographic variables (Model 1). It also predicted ATTR-CA among patients with unexplained hypertrophy regardless of a diagnostic score (IWT score). Patients with either LA-PALS or LA-peak atrial contraction strain (PACS) in the first quartile (LA-PALS &lt;6.65% or LA-PACS &lt;3.62%) had an almost 4-fold higher likelihood of CA and ATTR-CA regardless of Model 1. Among patients with unexplained hypertrophy, those with LA-PALS or LA-PACS in the first quartile had an almost 9-fold higher likelihood of ATTR-CA irrespective of Model 1, and a 2-fold higher likelihood of ATTR-CA beyond the IWT score.

Conclusions

STE measures of all two chambers are abnormal in patients with CA, particularly in those with ATTR-CA. LA strain holds independent diagnostic significance. Among patients screened for CA, those with LA-PALS &lt;6.65% and/or LA-PACS &lt;3.62% have a high likelihood of CA and ATTR-CA.

41 Circulating levels and prognostic cut-offs of sST2, high-sensitivity troponin T, and NT-proBNP in women vs. men with chronic heart failure

Aims

Limited evidence exists on sex-related differences in clinical value of biomarkers in chronic heart failure (HF). We aimed to define plasma levels, determinants, and optimal prognostic cut-offs of soluble suppression of tumourigenesis-2 (sST2), high-sensitivity troponin T (hs-TnT), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in female and male chronic HF patients.

Methods and results

Individual data of patients from the BIOS (Biomarkers In Heart Failure Outpatient Study) Consortium with sST2, hs-TnT, and NT-proBNP measured were analysed. The primary endpoint was a composite of 1-year cardiovascular death and HF hospitalization. The secondary endpoints were 5-year cardiovascular and all-cause death. The cohort included 4540 patients (age: 67 ± 12 years, LVEF 33 ± 13%, 1111 women, 25%). Women showed lower sST2 (24 vs. 27 ng/ml, P &lt; 0.001) and hs-TnT level (15 vs. 20 ng/l, P &lt; 0.001), and similar concentrations of NT-proBNP (1540 vs. 1505 ng/l, P = 0.408). Although the three biomarkers were confirmed as independent predictors of outcome in both sexes, the optimal prognostic cut-off was lower in women for sST2 (28 vs. 31 ng/ml) and hs-TnT (22 vs. 25 ng/l), while NT-proBNP cut-off was higher in women (2339 ng/l vs. 2145 ng/l). The use of sex-specific cut-offs improved risk prediction compared to the use of previously standardized prognostic cut-offs (Figure).

Conclusions

In patients with chronic HF, levels of sST2 and hs-TnT, but not of NT-proBNP are lower in women. Lower sST2 and hs-TnT and higher NT-proBNP cut-offs for risk stratification could be used in women.

Deformation imaging by strain in chronic heart failure over sacubitril/valsartan: a multicenter echocardiographic registry (DISCOVER) ARNI

Background

Sacubitril/valsartan changed the treatment of heart failure with reduced ejection fraction (HFrEF), due to the positive effects morbidity and mortality partly mediated by left ventricular reverse remodeling (LVRR). The aim of this multicenter study was to identify echocardiographic predictors of LVRR after sacubitril/valsartan administration.

Methods

Patients with HFrEF requiring therapy with sacubitril/valsartan from 13 Italian centers were included. Echocardiographic indexes including speckle tracking echocardiography (STE) were used to predict LVRR (defined as LV end-systolic volume reduction and ejection fraction [LVEF] improvement &gt;10% at follow-up) at 6 months follow-up as the primary endpoint. Changes in symptoms (NYHA class) and neurohormonal activations (N-terminal-pro-brain natriuretic peptide [NTproBNP]) were also evaluated as secondary endpoints. Patients with poor acoustic windows and missing data were excluded.

Results

The final population consisted of 341 patients (mean age: 65±10 years; 18% female, median LVEF 30% [interquartile range:25; 34]. At 6 months follow-up, cardiac dimensions and function, including left heart STE parameters, improved (Table 1). Moreover, 82 (24%) patients showed early complete response (LVRR and LVEF ≥35%), 55 (16%) early incomplete response (LVRR and LVEF &lt;35%), 204 (60%) no response (no LVRR and LVEF &lt;35%) after 6 months of sacubitril/valsartan. Among patients with ischemic etiology, 68% (108) did not develop LV RR. Age, sex, general characteristics, baseline NYHA class and NT-pro BNP did not significantly differ between the groups.Conversely, baseline LV dimensions and LVEF showed significant differences between the groups (p&lt;0.0001). Also, STE parameters were considerably better in group 1 compared to group 2 and 3 both at baseline and follow-up. Non-ischemic etiology, a lower left atrial volume index and a higher global longitudinal strain were all independent predictors of LVRR at multivariable logistic analysis (all p&lt;0.01). With ROC and spline curves, LV GLS &gt;−9.3% showed a good accuracy in predicting LV RR (Figure 1). LA strain was the best predictor of positive changes in NYHA class and NT-proBNP (all p&lt;0.05).

Conclusions

STE parameters at baseline could be useful to predict LVRR and early clinical response to sacubitril-valsartan, and thus could be used as a guide for treatment in patients with HFrEF.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Reverse remodelling criteria to predict cardiovascular death in heart failure with reduced or mid-range ejection fraction

Aims

Reverse remodelling (RR) is the recovery from left ventricle (LV) dilatation and dysfunction. There are no established definitions of RR. We sought to identify RR criteria that better predicted cardiovascular death.

Methods and results

Forty-two studies used 25 criteria to define RR, most commonly (n=12) as LV end-systolic volume (LVESV) reduction ≥15%. We evaluated 927 patients with LV ejection fraction (LVEF) &lt;50% undergoing 2 echocardiograms within 12±2 months. Over a median 2.8-year follow-up after the second echocardiogram (1.3–4.9), 123 cardiovascular deaths occurred (13%). Model 1 included age, LVEF, N-terminal pro-B-type natriuretic peptide (NT-proBNP), ischaemic aetiology, cardiac resynchronization therapy (CRT), estimated glomerular filtration rate (eGFR), New York Heart Association (NYHA), and LVESV index (LVESVi), and Model 2 the validated 3C-HF score. Two RR criteria proved particularly effective in risk reclassification over Model 1 and Model 2: LVEF increase ≥1 category (severe [LVEF ≤30%], moderate [LVEF 31–40%], mild LV dysfunction [LVEF 41–55%] and normal LV function [LVEF ≥56%]), and LVEF increase &gt;10 U. The same 2 criteria yielded independent prognostic significance and improved reclassification also in patients with LVEF &lt;40% or LVEF ≤35%. LVEF increase ≥1 category and LVEF increase &gt;10 U displayed a stronger prognostic value than LVESV reduction ≥15%, both in the whole population and the subsets with LVEF &lt;40% or ≤35%.

Funding Acknowledgement

Type of funding sources: None.

Mapping dependencies of BOLD signal change to end-tidal CO2: linear and nonlinear modeling, and effect of physiological noise correction

BACKGROUND

Disentangling physiological noise and signal of interest is a major issue when evaluating BOLD-signal changes in response to breath holding. Currently-adopted approaches for retrospective noise correction are general-purpose, and have non-negligible effects in studies on hypercapnic challenges.

NEW METHOD

We provide a novel approach to the analysis of specific and non-specific BOLD-signal changes related to end-tidal CO₂ (P_ETCO₂) in breath-hold fMRI studies. Multiple-order nonlinear predictors for P_ETCO₂ model a region-dependent nonlinear input-output relationship hypothesized in literature and possibly playing a crucial role in disentangling noise. We explore Retrospective Image-based Correction (RETROICOR) effects on the estimated BOLD response, applying our analysis both with and without RETROICOR and analyzing the linear and non-linear correlation between P_ETCO₂ and RETROICOR regressors.

RESULTS

The RETROICOR model of noise related to respiratory activity correlated with P_ETCO₂ both linearly and non-linearly. The correction affected the shape of the estimated BOLD response to hypercapnia but allowed to discard spurious activity in ventricles and white matter. Activation clusters were best detected using non-linear components in the BOLD response model.

COMPARISON WITH EXISTING METHOD

We evaluated the side-effects of standard physiological noise correction procedure, tailoring our analysis on challenging understudied brainstem and subcortical regions. Our novel approach allowed to characterize delays and non-linearities in BOLD response.

CONCLUSIONS

RETROICOR successfully avoided false positives, still broadly affecting the estimated non-linear BOLD responses. Non-linearities in the model better explained CO₂-related BOLD signal fluctuations. The necessity to modify the standard procedure for physiological-noise correction in breath-hold studies was addressed, stating its crucial importance.

Current and emerging drug targets in heart failure treatment

After initial strategies targeting inotropism and congestion, the neurohormonal interpretative model of heart failure (HF) pathophysiology has set the basis for current pharmacological management of HF, as most of guideline recommended drug classes, including beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and mineralocorticoid receptor antagonists, blunt the activation of detrimental neurohormonal axes, namely sympathetic and renin–angiotensin–aldosterone (RAAS) systems. More recently, sacubitril/valsartan, a first-in-class angiotensin receptor neprilysin inhibitor, combining inhibition of RAAS and potentiation of the counter-regulatory natriuretic peptide system, has been consistently demonstrated to reduce mortality and HF-related hospitalization. A number of novel pharmacological approaches have been tested during the latest years, leading to mixed results. Among them, drugs acting directly at a second messenger level, such as the soluble guanylate cyclase stimulator vericiguat, or other addressing myocardial energetics and mitochondrial function, such as elamipretide or omecamtiv-mecarbil, will likely change the therapeutic management of patients with HF. Sodium glucose cotransporter 2 inhibitors, initially designed for the management of type 2 diabetes mellitus, have been recently demonstrated to improve outcome in HF, although mechanisms of their action on cardiovascular system are yet to be elucidated. Most of these emerging approaches have shifted the therapeutic target from neurohormonal systems to the heart, by improving cardiac contractility, metabolism, fibrosis, inflammation, and remodeling. In the present paper, we review from a pathophysiological perspective current and novel therapeutic strategies in chronic HF.

The ergoreflex: how the skeletal muscle modulates ventilation and cardiovascular function in health and disease

The control of ventilation and cardiovascular function during physical activity is partially regulated by the ergoreflex, a cardiorespiratory reflex activated by physical activity. Two components of the ergoreflex have been identified: the mechanoreflex, which is activated early by muscle contraction and tendon stretch, and the metaboreflex, which responds to the accumulation of metabolites in the exercising muscles. Patients with heart failure (HF) often develop a skeletal myopathy with varying degrees of severity, from a subclinical disease to cardiac cachexia. HF‐related myopathy has been associated with increased ergoreflex sensitivity, which is believed to contribute to dyspnoea on effort, fatigue and sympatho‐vagal imbalance, which are hallmarks of HF. Ergoreflex sensitivity increases significantly also in patients with neuromuscular disorders. Exercise training is a valuable therapeutic option for both HF and neuromuscular disorders to blunt ergoreflex sensitivity, restore the sympatho‐vagal balance, and increase tolerance to physical exercise. A deeper knowledge of the mechanisms mediating ergoreflex sensitivity might enable a drug or device modulation of this reflex when patients cannot exercise because of advanced skeletal myopathy.

NT-proBNP for Risk Prediction in Heart Failure: Identification of Optimal Cutoffs Across Body Mass Index Categories

OBJECTIVES

The goal of this study was to assess the predictive power of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and the decision cutoffs in heart failure (HF) across body mass index (BMI) categories.

BACKGROUND

Concentrations of NT-proBNP predict outcome in HF. Although the influence of BMI to reduce levels of NT-proBNP is known, the impact of obesity on prognostic value remains uncertain.

METHODS

Individual data from the BIOS (Biomarkers In Heart Failure Outpatient Study) consortium were analyzed. Patients with stable HF were classified as underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5-24.9 kg/m²), overweight (BMI 25-29.9 kg/m²), and mildly (BMI 30-34.9 kg/m²), moderately (BMI 35-39.9 kg/m²), or severely (BMI ≥40 kg/m²) obese. The prognostic role of NT-proBNP was tested for the endpoints of all-cause and cardiac death.

RESULTS

The study population included 12,763 patients (mean age 66 ± 12 years; 25% women; mean left ventricular ejection fraction 33% ± 13%). Most patients were overweight (n = 5,176), followed by normal weight (n = 4,299), mildly obese (n = 2,157), moderately obese (n = 612), severely obese (n = 314), and underweight (n = 205). NT-proBNP inversely correlated with BMI (β = -0.174 for 1 kg/m²; P < 0.001). Adding NT-proBNP to clinical models improved risk prediction across BMI categories, with the exception of severely obese patients. The best cutoffs of NT-proBNP for 5-year all-cause death prediction were lower as BMI increased (3,785 ng/L, 2,193 ng/L, 1,554 ng/L, 1,045 ng/L, 755 ng/L, and 879 ng/L, for underweight, normal weight, overweight, and mildly, moderately, and severely obese patients, respectively) and were higher in women than in men.

CONCLUSIONS

NT-proBNP maintains its independent prognostic value up to 40 kg/m² BMI, and lower optimal risk-prediction cutoffs are observed in overweight and obese patients.

Effects of nasal high flow on sympathovagal balance, sleep, and sleep-related breathing in patients with precapillary pulmonary hypertension

BACKGROUND

In precapillary pulmonary hypertension (PH), nasal high flow therapy (NHF) may favorably alter sympathovagal balance (SVB) and sleep-related breathing through washout of anatomical dead space and alleviation of obstructive sleep apnea (OSA) due to generation of positive airway pressure.

OBJECTIVES

To investigate the effects of NHF on SVB, sleep, and OSA in patients with PH, and compare them with those of positive airway pressure therapy (PAP).

METHODS

Twelve patients with PH (Nice class I or IV) and confirmed OSA underwent full polysomnography, and noninvasive monitoring of SVB parameters (spectral analysis of heart rate, diastolic blood pressure variability). Study nights were randomly split into four 2-h segments with no treatment, PAP, NHF 20 L/min, or NHF 50 L/min. In-depth SVB analysis was conducted on 10-min epochs during daytime and stable N2 sleep at nighttime.

RESULTS

At daytime and compared with no treatment, NHF20 and NHF50 were associated with a flow-dependent increase in peripheral oxygen saturation but a shift in SVB towards increased sympathetic drive. At nighttime, NHF20 was associated with increased parasympathetic drive and improvements in sleep efficiency, but did not alter OSA severity. NHF50 was poorly tolerated. PAP therapy improved OSA but had heterogenous effects on SVB and neutral effects on sleep outcomes. Hemodynamic effects were neutral for all interventions.

CONCLUSIONS

In sleeping PH patients with OSA NHF20 but not NHF50 leads to decreased sympathetic drive likely due to washout of anatomical dead space. NHF was not effective in lowering the apnea-hypopnoea index and NHF50 was poorly tolerated.

Heterogeneity of right ventricular refractory period: a novel prognostic predictor in type-1 Brugada

Funding Acknowledgements

Type of funding sources: None.

Risk stratification in Brugada syndrome (BrS) is needed especially for the choice of an Implantable Cardiac Defibrillator (ICD). To date the predictive value of either clinical or conventional electrophysiological indexes in type 1 electrocardiographic pattern BrS is rather low.

We aimed to evaluate the eventual prognostic significance of refractoriness heterogeneity of right ventricular outflow tract, an emergent relevant pathophysiological substrate, at electrophysiological study (EPS) in patients with BrS.

From 5 centers 348 patients were retrospectively selected (age 44 ± 15 years, males 68%). Eighty-five (24%) patients had an ICD. EPS was proposed in patients with spontaneous type-1 ECG pattern regardless of symptoms, or in patients with drug-induced type-1 ECG pattern with symptoms (n = 174). The difference in the refractory period between the right ventricular outflow tract and the apex (ΔRPRVOT-apex) at EPS was evaluated as a prognostic factor. The optimal ΔRPRVOT-apex cutpoint for prognosis prediction was calculated through a P-spline hazard ratio analysis. Thus, ΔRPRVOT-apex  was compared through different statistical analyses to other other clinical or conventional electrophysiological prognostic indexes previosly described in literature. 

During a 36-month median follow-up (range 6-228) 3 SCD and 10 appropriate ICD shocks (aborted SCD, aSCD) occurred. Fifty patients (29%) had a positive EPS (induction of sustained ventricular tachycardia, VT, or ventricular fibrillation, VF, during the procedure). At multivariable logistic analysis, only ΔRPRVOT-apex  and late potentials remained independent predictors of a positive EPS. At Cox Proportional Hazard analysis, family history of SCD, history of syncope, VT/VF inducibility and a ΔRPRVOT-apex &gt;60 ms were all univariate predictors of SCD/aSCD. At bivariate analysis, a ΔRPRVOT-apex &gt;60 ms remained an independent predictor of SCD/aSCD even when adjusted the other univariate predictors. At C-Statistic analysis, the strongest predictive model was the one using ΔRPRVOT-apex &gt;60 ms as covariate with a C-statistics (95% CI) of 0.72 (0.51-0.93). At Kaplan-Meyer curves, ΔRPRVOT-apex &gt;60 ms was confirmed a strong predictor of SCD/aSCD and another very interesting observation was possible: patients with positive EPS, but a ΔRPRVOT-apex &lt; 60 ms, had a similar risk to SCD/aSCD compared to patients with a negative EPS, while those with a positive EPS and a ΔRPRVOT-apex &gt; 60 ms were found to be at a higher risk of events.

Refractory period heterogeneity of the right ventricle defined as ΔRPRVOT-apex &gt; 60 ms at EPS is a strong and independent predictor of SCD/aSCD in patients with BrS, beyond VT/VF inducibility at EPS and common clinical predictors. Abstract Figure.

Prognostic value of reverse remodelling criteria in heart failure with reduced or mid-range ejection fraction

Aims

Reverse remodelling (RR) is the recovery from left ventricular (LV) dilatation and dysfunction. Many arbitrary criteria for RR have been proposed. We searched the criteria with the strongest prognostic yield for the hard endpoint of cardiovascular death.

Methods and results

We performed a systematic literature search of diagnostic criteria for RR. We evaluated their prognostic significance in a cohort of 927 patients with LV ejection fraction (LVEF) < 50% undergoing two echocardiograms within 12 ± 2 months. These patients were followed for a median of 2.8 years (interquartile interval 1.3–4.9) after the second echocardiogram, recording 123 cardiovascular deaths. Two prognostic models were defined. Model 1 included age, LVEF, N‐terminal pro‐B‐type natriuretic peptide, ischaemic aetiology, cardiac resynchronization therapy, estimated glomerular filtration rate, New York Heart Association, and LV end‐systolic volume (LVESV) index, and Model 2 the validated Cardiac and Comorbid Conditions Heart Failure score. We identified 25 criteria for RR, the most used being LVESV reduction ≥15% (12 studies out of 42). In the whole cohort, two criteria proved particularly effective in risk reclassification over Model 1 and Model 2. These criteria were (i) LVEF increase >10 U and (ii) LVEF increase ≥1 category [severe (LVEF ≤ 30%), moderate (LVEF 31–40%), mild LV dysfunction (LVEF 41–55%), and normal LV function (LVEF ≥ 56%)]. The same two criteria yielded independent prognostic significance and improved risk reclassification even in patients with more severe systolic dysfunction, namely, those with LVEF < 40% or LVEF ≤ 35%. Furthermore, LVEF increase >10 U and LVEF increase ≥1 category displayed a greater prognostic value than LVESV reduction ≥15%, both in the whole cohort and in the subgroups with LVEF < 40% or LVEF ≤ 35%. For example, LVEF increase >10 U independently predicted cardiovascular death over Model 1 and LVESV reduction ≥15% (hazard ratio 0.40, 95% confidence interval 0.18–0.90, P = 0.026), while LVESV reduction ≥15% did not independently predict cardiovascular death (P = 0.112).

Conclusions

Left ventricular ejection fraction increase >10 U and LVEF increase ≥1 category are stronger predictors of cardiovascular death than the most commonly used criterion for RR, namely, LVESV reduction ≥15%.

Epidemiological and clinical boundaries of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is highly prevalent and is associated with relevant morbidity and mortality. However, an evidence-based treatment is still absent. The heterogeneous definitions, differences in aetiology/pathophysiology, and diagnostic challenges of HFpEF made it difficult to define its epidemiological landmarks so far. Several large registries and observational studies have recently disclosed an increasing incidence/prevalence, as well as its prognostic significance. An accurate definition of HFpEF epidemiological boundaries and phenotypes is mandatory to develop novel effective and rational therapeutic approaches.

A simple echocardiographic score to rule out cardiac amyloidosis

BACKGROUND

Early diagnosis of cardiac amyloidosis (CA) is warranted to initiate specific treatment and improve outcome. The amyloid light chain (AL) and inferior wall thickness (IWT) scores have been proposed to assess patients referred by haematologists or with unexplained left ventricular (LV) hypertrophy, respectively. These scores are composed of 4 or 5 variables, respectively, including strain data.

METHODS

Based on 2 variables common to the AL and IWT scores, we defined a simple score named AMYLoidosis Index (AMYLI) as the product of relative wall thickness (RWT) and E/e' ratio, and assessed its diagnostic performance.

RESULTS

In the original cohort (n = 251), CA was ultimately diagnosed in 111 patients (44%). The 2.22 value was selected as rule-out cut-off (negative likelihood ratio [LR-] 0.0). In the haematology subset, AL CA was diagnosed in 32 patients (48%), with 2.36 as rule-out cut-off (LR- 0.0). In the hypertrophy subset, ATTR CA was diagnosed in 79 patients (43%), with 2.22 as the best rule-out cut-off (LR- 0.0). In the validation cohort (n = 691), the same cut-offs proved effective: indeed, there were no patients with CA in the whole population or in the haematology or hypertrophy subsets scoring < 2.22, <2.36 or < 2.22, respectively.

CONCLUSIONS

The AMYLI score (RWT*E/e') may have a role as an initial screening tool for CA. A < 2.22 value excludes the diagnosis in patients undergoing a diagnostic screening for CA, while a < 2.36 and a < 2.22 value may be better considered in the subsets with suspected cardiac AL amyloidosis or unexplained hypertrophy, respectively.

Sleep-Disordered Breathing and Nocturnal Hypoxemia in Precapillary Pulmonary Hypertension: Prevalence, Pathophysiological Determinants, and Clinical Consequences

BACKGROUND AND OBJECTIVE

The clinical relevance and interrelation of sleep-disordered breathing and nocturnal hypoxemia in patients with precapillary pulmonary hypertension (PH) is not fully understood.

METHODS

Seventy-one patients with PH (age 63 ± 15 years, 41% male) and 35 matched controls were enrolled. Patients with PH underwent clinical examination with assessment of sleep quality, daytime sleepiness, 6-minute walk distance (6MWD), overnight cardiorespiratory polygraphy, lung function, hypercapnic ventilatory response (HCVR; by rebreathing technique), amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac MRI (n = 34).

RESULTS

Prevalence of obstructive sleep apnea (OSA) was 68% in patients with PH (34% mild, apnea-hypopnea index [AHI] ≥5 to <15/h; 34% moderate to severe, AHI ≥15/h) versus 5% in controls (p < 0.01). Only 1 patient with PH showed predominant central sleep apnea (CSA). Nocturnal hypoxemia (mean oxygen saturation [SpO2] <90%) was present in 48% of patients with PH, independent of the presence of OSA. There were no significant differences in mean nocturnal SpO2, self-reported sleep quality, 6MWD, HCVR, and lung and cardiac function between patients with moderate to severe OSA and those with mild or no OSA (all p > 0.05). Right ventricular (RV) end-diastolic (r = -0.39; p = 0.03) and end-systolic (r = -0.36; p = 0.04) volumes were inversely correlated with mean nocturnal SpO2 but not with measures of OSA severity or daytime clinical variables.

CONCLUSION

OSA, but not CSA, is highly prevalent in patients with PH, and OSA severity is not associated with nighttime SpO2, clinical and functional status. Nocturnal hypoxemia is a frequent finding and (in contrast to OSA) relates to structural RV remodeling in PH.

Sacubitril-valsartan treatment is associated with decrease in central apneas in patients with heart failure with reduced ejection fraction

BACKGROUND

To assess the impact of sacubitril-valsartan on apneic burden in patients with heart failure with reduced ejection fraction (HFrEF), 51 stable HFrEF patients planned for switching from an ACE-i/ARB to sacubitril-valsartan were prospectively enrolled.

METHODS AND RESULTS

At baseline and after 6 months of treatment, all patients underwent echocardiography, 24-h cardiorespiratory monitoring, neurohormonal evaluation, and cardiopulmonary exercise testing. At baseline 29% and 65% of patients presented with obstructive and central apneas, respectively. After 6 months, sacubitril-valsartan was associated with a decrease in NT-proBNP, improvement in LV function, functional capacity and ventilatory efficiency. After treatment, the apnea-hypopnea index (AHI) decreased across the 24-h period (p < 0.001), as well as at daytime (p < 0.001) and at nighttime (p = 0.026), proportionally to baseline severity. When subgrouping according to the type of apneas, daytime, nighttime and 24-h AHI decreased in patients with central apneas (all p < 0.01). Conversely, in patients with obstructive apneas, the effect of drug administration was neutral at nighttime, with significant decrease only in daytime events (p = 0.007), mainly driven by reduction in hypopneas.

CONCLUSIONS

Sacubitril-valsartan on top of medical treatment is associated with a reduction in the apneic burden among a real-life cohort of HFrEF patients. The most marked reduction was observed for central apneas.

A novel echocardiographic method for estimation of pulmonary artery wedge pressure and pulmonary vascular resistance

Aims

This study aimed to evaluate a novel echocardiographic algorithm for quantitative estimation of pulmonary artery wedge pressure (PAWP) and pulmonary vascular resistance (PVR) in patients with heart failure and pulmonary hypertension (PH) scheduled to right heart catheterization (RHC).

Methods and results

In this monocentric study, 795 consecutive patients (427 men; age 68.4 ± 12.1 years) undergoing echocardiography and RHC were evaluated. Multiple regression analysis was performed to identify echocardiographic predictors of PAWP and PVR measured by RHC in the derivation group (the first 200 patients). The diagnostic accuracy of the model was then tested in the validation group (the remaining 595 patients). PH was confirmed by RHC in 507 (63.8%) patients, with 192 (24.2%) cases of precapillary PH, 248 (31.2%) of postcapillary PH, and 67 (8.4%) of combined PH. At regression analysis, tricuspid regurgitation maximal velocity, mitral E/e′ ratio, left ventricular ejection fraction, right ventricular fractional area change, inferior vena cava diameter, and left atrial volume index were included in the model (R = 0.8, P < 0.001). The model showed a high diagnostic accuracy in estimating elevated PAWP (area under the receiver operating characteristic curve = 0.97, 92% sensitivity, and 93% specificity, P < 0.001) and PVR (area under the receiver operating characteristic curve = 0.96, 89% sensitivity, and 92% specificity, P < 0.001), outperforming 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations (P < 0.001) and Abbas' equation (P < 0.001). Bland–Altman analysis showed satisfactory limits of agreement between echocardiography and RHC for PAWP (bias 0.7, 95% confidence interval −7.3 to 8.7) and PVR (bias −0.1, 95% confidence interval −2.2 to 1.9 Wood units), without indeterminate cases.

Conclusions

A novel quantitative echocardiographic approach for the estimation of PAWP and PVR has high diagnostic accuracy in patients with heart failure and PH.

Breath-hold task induces temporal heterogeneity in electroencephalographic regional field power in healthy subjects

We demonstrated that changes in CO₂ values cause oscillations in the cortical activity in δ-and α-bands. The analysis of the regional field power (RFP) showed evidence that different cortical areas respond with different time delays to CO₂ challenges. An opposite behavior was found for the end-tidal O₂. We suppose that the different cortical time delays likely expresse specific ascending pathways to the cortex, generated by chemoreceptor nuclei in the brain stem. Although the brain stem is in charge of the automatic control of ventilation, the cortex is involved in the voluntary control of breathing but also receives inputs from the brain stem, which influences the perception of breathing, the arousal state and sleep architecture in conditions of hypoxia/hypercapnia. We evaluated in 11 healthy subjects the effects of breath hold (BH; 30 s of apneas and 30 s of normal breathing) and BH-related CO₂/O₂ changes on electroencephalogram (EEG) global field power (GFP) and RFP in nine different areas (3 rostrocaudal sections: anterior, central, and posterior; and 3 sagittal sections: left, middle, and right) in the δ- and α-bands by cross correlation analysis. No significant differences were observed in GFP or RFP when comparing free breathing (FB) with the BH task. Within the BH task, the shift from apnea to normal ventilation was accompanied by an increase in the δ-power and a decrease in the α-power. The end-tidal pressure of CO₂ ([Formula: see text]) was positively correlated with the δ-band and negatively with the α- band with a positive time shift, whereas an opposite behavior was found for the end-tidal pressure of O₂ ([Formula: see text]). Notably, the time shift between [Formula: see text] / [Formula: see text] signals and cortical activity at RFP was heterogenous and seemed to follow a hierarchical activation, with the δ-band responding earlier than the α-band. Overall, these findings suggest that the effect of BH on the cortex may follow specific ascending pathways from the brain stem and be related to chemoreflex stimulation.NEW & NOTEWORTHY We demonstrated that the end tidal CO₂ oscillation causes oscillations of delta and alpha bands. The analysis of the regional field power showed that different cortical areas respond with different time delays to CO₂ challenges. An opposite behavior was found for the end-tidal O₂. We can suppose that the different cortical time delay response likely expresses specific ascending pathways to the cortex generated by chemoreceptor nuclei in the brainstem.

Renin profiling predicts neurohormonal response to sacubitril/valsartan

AIMS

Clinical trials and observational cohorts show that beneficial effects of sacubitril/valsartan are less strong in an appreciable proportion of patients with heart failure with reduced ejection fraction (HFrEF). Lower blood pressure and impaired renal function predict suboptimal sacubitril/valsartan titration and a less favourable response. Circulating renin encompasses neurohormonal activation, intravascular volume, and renal function. We hypothesized that renin may predict response to sacubitril/valsartan, assessed by changes in N-terminal fraction of pro-brain natriuretic peptide (NT-proBNP).

METHODS AND RESULTS

We performed a prospective, open-label, real-life cohort study. The study population consisted of 80 consecutive HFrEF patients (age 66 ± 10 years, 83% men) planned to initiate sacubitril/valsartan. Clinical and biohumoral assessment, including a full neurohormonal panel, was performed at baseline and at 1, 3, and 6 month follow-up. Response to sacubitril/valsartan was defined as ≥30% reduction in NT-proBNP levels from baseline to 6 months. Patients in the lower renin tertile had higher blood pressure and plasma sodium concentration (all P < 0.05). At follow-up, 38 patients (48%) were classified as responders. Circulating renin was lower in the responder group compared with non-responders (19.8 mU/L, IQR 3.7-78.0 mU/L vs. 55.0 mU/L, IQR 16.4-483.1 mU/L; P = 0.004). After adjustment for age, renal function, and blood pressure, renin was independently associated to response to sacubitril/valsartan (P = 0.018).

CONCLUSIONS

In our preliminary study, we show that circulating renin predicts reduction in NT-proBNP levels after sacubitril/valsartan initiation in HFrEF patients. Renin assessment might be useful to discriminate potential responders from the subgroup with a weaker expected benefit, thus needing a closer, tailored management strategy.

Heart Failure Results in Inspiratory Muscle Dysfunction Irrespective of Left Ventricular Ejection Fraction

BACKGROUND

Exercise intolerance in heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF) results from both cardiac dysfunction and skeletal muscle weakness. Respiratory muscle dysfunction with restrictive ventilation disorder may be present irrespective of left ventricular ejection fraction and might be mediated by circulating pro-inflammatory cytokines.

OBJECTIVE

To determine lung and respiratory muscle function in patients with HFrEF/HFpEF and to determine its associations with exercise intolerance and markers of systemic inflammation.

METHODS

Adult patients with HFrEF (n = 22, 19 male, 61 ± 14 years) and HFpEF (n = 8, 7 male, 68 ± 8 years) and 19 matched healthy control subjects underwent spirometry, measurement of maximum mouth occlusion pressures, diaphragm ultrasound, and recording of transdiaphragmatic and gastric pressures following magnetic stimulation of the phrenic nerves and the lower thoracic nerve roots. New York Heart Association (NYHA) class and 6-min walking distance (6MWD) were used to quantify exercise intolerance. Levels of circulating interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured using ELISAs.

RESULTS

Compared with controls, both patient groups showed lower forced vital capacity (FVC) (p < 0.05), maximum inspiratory pressure (PImax), maximum expiratory pressure (PEmax) (p < 0.05), diaphragm thickening ratio (p = 0.01), and diaphragm strength (twitch transdiaphragmatic pressure in response to supramaximal cervical magnetic phrenic nerve stimulation) (p = 0.01). In patients with HFrEF, NYHA class and 6MWD were both inversely correlated with FVC, PImax, and PEmax. In those with HFpEF, there was an inverse correlation between amino terminal pro B-type natriuretic peptide levels and FVC (r = -0.77, p = 0.04). In all HF patients, IL-6 and TNF-α were statistically related to FVC.

CONCLUSIONS

Irrespective of left ventricular ejection fraction, HF is associated with respiratory muscle dysfunction, which is associated with increased levels of circulating IL-6 and TNF-α.

Central and obstructive apneas prevalence in heart failure with reduced, mid-range and preserved ejection fraction

Background

Central apneas (CA) and obstructive apneas (OA) are highly prevalent in heart failure (HF) both with reduced and preserved systolic function. However, a comprehensive evaluation of apnea prevalence across HF according to ejection fraction (i.e HF with patients with reduced, mid-range and preserved ejection fraction- HFrEf, HFmrEF and HFpEF, respectively) throughout the 24 hours has never been done before.

Materials and methods

700 HF patients were prospectively enrolled and then divided according to left ventricular EF (408 HFrEF, 117 HFmrEF, 175 HFpEF). All patients underwent a thorough evaluation including: 2D echocardiography; 24-h Holter-ECG monitoring; cardiopulmonary exercise testing; neuro-hormonal assessment and 24-h cardiorespiratory monitoring.

Results

In the whole population, prevalence of normal breathing (NB), CA and OA at daytime was 40%, 51%, and 9%, respectively, while at nighttime 15%, 55%, and 30%, respectively.

When stratified according to left ventricular EF, CA prevalence decreased from HFrEF to HFmrEF and HFpEF: (daytime CA: 57% vs. 43% vs. 42%, respectively, p=0.001; nighttime CA: 66% vs. 48% vs. 34%, respectively, p&lt;0.0001), while OA prevalence increased (daytime OA: 5% vs. 8% vs. 18%, respectively, p&lt;0.0001; nighttime OA: 20 vs. 29 vs. 53%, respectively, p&lt;0.0001).

When assessing moderte-severe apneas, defined with an apnea/hypopnea index &gt;15 events/hour, prevalence of CA was again higher in HFrEF than HFmrEF and HFpEF both at daytime (daytime moderate-severe CA: 28% vs. 19% and 23%, respectively, p&lt;0.05) and at nighttime (nighttime moderate-severe CA: 50% vs. 39% and 28%, respectively, p&lt;0.05). Conversely, moderate-severe OA decreased from HFrEF to HFmrEF to HFpEF both at daytime (daytime moderate-severe OA: 1% vs. 3% and 8%, respectively, p&lt;0.05) and nighttime (noghttime moderate-severe OA: 10% vs. 11% and 30%, respectively, p&lt;0.05).

Conclusions

Daytime and nighttime apneas, both central and obstructive in nature, are highly prevalent in HF regardless of EF. Across the whole spectrum of HF, CA prevalence increases and OA decreases as left ventricular systolic dysfunction progresses, both during daytime and nighttime.

Funding Acknowledgement

Type of funding source: None

Central apneas and Ticagrelor related dyspnea in patients with acute coronary syndrome

Background

Patients treated with ticagrelor often develop dyspnea of unknown origin. We aim to explore the contribution of central apneas to ticagrelor-related dyspnea in patients with acute coronary syndrome (ACS).

Methods

We consecutively enrolled patients with ACS, preserved left ventricular ejection fraction and no history of obstructive sleep apnea, treated either with ticagrelor 90 mg bid (n=30) or prasugrel 10 mg od (n=24). One week after ACS onset, all patients underwent, beyond thorough cardiovascular and respiratory assessment, 24-hour cardiorespiratory monitoring and assessment of chemosensitivity to hypercapnia.

Results

Patients treated with ticagrelor reported more frequently dyspnea than patients treated with prasugrel (43% versus 4%, p=0.001), despite no difference in demographic, clinical, echocardiographic and pulmonary data. Patients with dyspnea induced by ticagrelor showed higher apnea-hypopnea and central apnea index both at daytime and at nighttime compared to patients treated with ticagrelor but without dyspnea and patients treated with prasugrel (daytime AHI: 26 [7–34] vs 6 [4–14] and 6 [0–11] events/hour; nighttime AHI: 65 [17–72] vs 22 [8–37] and vs 11 [4–23] events/hour; daytime CAI: 5 [1–15] vs 1 [0–6] and 0 [0–1) events/hour; nighttime CAI 34 [2–55] vs 3 [0–9] and 0 [0–1], all p&lt;0.05). Likewise, they also presented with higher hypercapnic ventilatory response (2.4 [1.9–2.7] vs 1.3 [1.1–1.9] and 0.9 [0.5–2.1] L/min/mmHg, all p&lt;0.05).

Conclusions

Central apneas should be considered a likely mechanism of dyspnea in ACS patients treated with ticagrelor. A drug-related sensitization of the chemoreflex may be the cause of ventilatory instability in this setting.

Funding Acknowledgement

Type of funding source: None

Sacubitril/valsartan improves ventilation stability in patients with chronic heart failure

Background

Sacubitril/valsartan (SV) ameliorates symptoms and prognosis in patients with heart failure and reduced ejection fraction (HFrEF), but the reasons for such effects are unclear. The impact of SV on ventilation has never been investigated. In HFrEF, apneas are highly prevalent both at daytime and nighttime and are associated with increased mortality.

Purpose

We hypothesize that treatment with SV could favourably stabilize ventilation by reducing the severity of central apneas in patients with HFrEF.

Methods

51 patients with HFrEF (mean age 67±9 years, mean left ventricular ejection fraction, LVEF 27±7%) and apneas defined by an apnea-hypopnea index, AHI≥5 (median 16, interquartile range 8–28) events/hour, eligible to treatment with SV and previously on optimal medical therapy for HFrEF, were enrolled. An extensive evaluation including cardiac ultrasound and a 24-hour cardiorespiratory monitoring was performed.

Results

After six months of treatment with SV, left ventricle systolic and diastolic function, mitral regurgitation (MR), left atrial volume (LAVI) and systolic pulmonary artery pressure (sPAP) were improved. Severity of apneas was reduced by 50%, 65% and 36% throughout the 24-hour, at daytime and nighttime, respectively.

Conclusion

Besides its known efficacy on cardiac remodeling, SV positively decreases the apneic burden in patients with HFrEF.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Roche Diagnostics unrestricted grant

Reverse remodelling, changes in diastolic function and their prognostic value compared to natriuretic peptides

Background

Reverse remodelling (RR) is the recovery from left ventricular (LV) dilation and dysfunction in response to treatment for heart failure (HF). RR is usually associated with improved prognosis. The impact of RR on indices of diastolic function, and the relative prognostic value of RR, changes in diastolic function and natriuretic peptide levels are currently unknown.

Methods

We analysed data from patients with stable systolic HF (LV ejection fraction [LVEF] &lt;50%) undergoing 2 transthoracic echocardiograms (TTE) within 12±2 months. RR was defined as a ≥15% reduction in LV end-systolic volume index (LVESVi). The follow-up started after the second TTE.

Results

927 patients were evaluated (68±12 years; median LVEF 35% [interquartile interval 30–43%]; 27% women; 52% ischaemic aetiology). Patients experiencing RR (n=286, 31%) displayed more prominent positive changes in several parameters reflecting diastolic dysfunction, namely E/e' ratio, left atrial volume index (LAVi), and systolic pulmonary artery pressure (sPAP), as well as N-terminal fraction of pro-B-type natriuretic peptide (NT-proBNP; Figure). In the whole population, percent changes (Δ%) LVESVi displayed weak but significant correlations with Δ% E/e' (r=0.237, p&lt;0.001), LAVi (r=0.316, p&lt;0.001), and sPAP (r=0.158, p&lt;0.001), and also with Δ% NT-proBNP (r=0.279, p&lt;0.001). There were 123 cardiovascular deaths and 4 heart transplantations over 2.8 years (1.3–4.9). Δ% LVESVi, RR, Δ% sPAP and Δ% NT-proBNP were univariate predictors of this endpoint. In 2 multivariable models including Δ% sPAP and Δ% NT-proBNP and either RR or Δ% LVESVi, only Δ% NT-proBNP emerged as independent predictor of outcome (hazard ratio 1.01, 95% confidence interval 1.01–1.02; p&lt;0.001).

Conclusions

A recovery of LV geometry is accompanied by positive modifications in several indices related to diastolic function, as well as a decrease in NT-proBNP levels. Percent changes in NT-proBNP over 12 months are stronger predictors of outcome than variations in LV geometry or sPAP.

Funding Acknowledgement

Type of funding source: None

Two common echocardiographic variables to diagnose cardiac amyloidosis: the AMYLoidosis Index (AMYLI) score

Background

Early diagnosis of cardiac amyloidosis (CA) is warranted to initiate specific treatment and improve outcome. The amyloid light chain (AL) and inferior wall thickness (IWT) scores have been proposed to assess patients referred by hematologists or with unexplained left ventricular (LV) hypertrophy, respectively. These scores are composed of 4 or 5 variables, respectively, including strain data, and no decisional cut-offs were introduced.

Methods

Based on 2 variables common to the AL and IWT scores, we defined a simple score named AMYLoidosis Index (AMYLI) as the product of relative wall thickness (RWT) and E/e' ratio, and assessed its diagnostic performance. Optimal rule-out cut-offs were searched as those with negative likelihood ratio (LR−) &lt;0.1.

Results

In the derivation cohort (n=251), CA was ultimately diagnosed in 111 patients (44%). The 2.22 score value was selected as rule-out cut-off (LR- 0.0). In the hematology subset, AL CA was finally diagnosed in 32 patients (48%), with 2.36 as rule-out cut-off (LR− 0.0). In the hypertrophy subset, ATTR CA was diagnosed in 79 patients (43%), with 2.22 as best rule-out cut-off (LR− 0.0). In the validation cohort (n=691), where more patients were diagnosed with CA (94% and 68% in the hematology and in the hypertrophy subsets, respectively), the 2.22 rule-out cut-off had a LR− = ∞ (as no patient scoring &lt;2.22 had CA). In the hematology and hypertrophy subsets, the 2.36 and 2.22 cut-offs were effective for ruling-out CA, with both LR− = ∞ (as no patient scoring &lt;2.36 or 2.22, respectively, had CA).

Conclusions

The AMYLI score (RWT* E/e') is simpler than those proposed and similarly accurate. A 2.22 cut-off value excludes CA diagnosis in patients undergoing a diagnostic screening for CA, while a &lt;2.36 and a &lt;2.22 value may be better considered in the subsets with either blood dyscrasia or unexplained hypertrophy, respectively.

Funding Acknowledgement

Type of funding source: None

Treatment of cardiac transthyretin amyloidosis: an update

Transthyretin (TTR) is a tetrameric protein synthesized mostly by the liver. As a result of gene mutations or as an ageing-related phenomenon, TTR molecules may misfold and deposit in the heart and in other organs as amyloid fibrils. Cardiac involvement in TTR-related amyloidosis (ATTR) manifests typically as left ventricular pseudohypertrophy and/or heart failure with preserved ejection fraction. ATTR is an underdiagnosed disorder as well as a crucial determinant of morbidity and mortality, thus justifying the current quest for a safe and effective treatment. Therapies targeting cardiac damage and its direct consequences may yield limited benefit, mostly related to dyspnoea relief through diuretics. For many years, liver or combined heart and liver transplantation have been the only available treatments for patients with mutations causing ATTR, including those with cardiac involvement. The therapeutic options now include several pharmacological agents that inhibit hepatic synthesis of TTR, stabilize the tetramer, or disrupt fibrils. Following the positive results of a phase 3 trial on tafamidis, and preliminary findings on patisiran and inotersen in patients with ATTR-related neuropathy and cardiac involvement, we provide an update on this rapidly evolving field, together with practical recommendations on the management of cardiac involvement.