Rationale and design of the PACIFIC-PRESERVED (PhenomApping, ClassIFication and Innovation for Cardiac dysfunction in patients with heart failure and PRESERVED left ventricular ejection fraction) study.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome that is poorly defined, reflecting an incomplete understanding of its pathophysiology. AIM: To redefine the phenotypic spectrum of HFpEF. METHODS: The PACIFIC-PRESERVED study is a prospective multicentre cohort study designed to perform multidimensional deep phenotyping of patients diagnosed with HFpEF (left ventricular ejection fraction≥50%), patients with heart failure with reduced ejection fraction (left ventricular ejection fraction≤40%) and subjects without overt heart failure (3:2:1 ratio). The study proposes prospective investigations in patients during a 1-day hospital stay: physical examination; electrocardiogram; performance-based tests; blood samples; cardiac magnetic resonance imaging; transthoracic echocardiography (rest and low-level exercise); myocardial shear wave elastography; chest computed tomography; and non-invasive measurement of arterial stiffness. Dyspnoea, depression, general health and quality of life will be assessed by dedicated questionnaires. A biobank will be established. After the hospital stay, patients are asked to wear a connected garment (with digital sensors) to collect electrocardiography, pulmonary and activity variables in real-life conditions (for up to 14 days). Data will be centralized for machine-learning-based analyses, with the aim of reclassifying HFpEF into more distinct subgroups, improving understanding of the disease mechanisms and identifying new biological pathways and molecular targets. The study will also serve as a platform to enable the development of innovative technologies and strategies for the diagnosis and stratification of patients with HFpEF. CONCLUSIONS: PACIFIC-PRESERVED is a prospective multicentre phenomapping study, using novel analytical techniques, which will provide a unique data resource to better define HFpEF and identify new clinically meaningful subgroups of patients.

Development and validation of algorithms to predict left ventricular ejection fraction class from healthcare claims data.

AIMS: The use of large medical or healthcare claims databases is very useful for population-based studies on the burden of heart failure (HF). Clinical characteristics and management of HF patients differ according to categories of left ventricular ejection fraction (LVEF), but this information is often missing in such databases. We aimed to develop and validate algorithms to identify LVEF in healthcare databases where the information is lacking. METHODS AND RESULTS: Algorithms were built by machine learning with a random forest approach. Algorithms were trained and reinforced using the French national claims database [Système National des Données de Santé (SNDS)] and a French HF registry. Variables were age, gender, and comorbidities, which could be identified by medico-administrative code-based proxies, Anatomical Therapeutic Chemical codes for drug delivery, International Classification of Diseases (Tenth Revision) coding for hospitalizations, and administrative codes for any other type of reimbursed care. The algorithms were validated by cross-validation and against a subset of the SNDS that includes LVEF information. The areas under the receiver operating characteristic curve were 0.84 for the algorithm identifying LVEF ≤ 40% and 0.79 for the algorithms identifying LVEF < 50% and ≥50%. For LVEF ≤ 40%, the reinforced algorithm identified 50% of patients in the validation dataset with a positive predictive value of 0.88 and a specificity of 0.96. The most important predictive variables were delivery of HF medication, sex, age, hospitalization, and testing for natriuretic peptides with different orders of positive or negative importance according to the LVEF category. CONCLUSIONS: The algorithms identify reduced or preserved LVEF in HF patients within a nationwide healthcare claims database with high positive predictive value and low rates of false positives.

Pregnancy and cardiac maternal outcomes in women with inherited cardiomyopathy: interest of the CARPREG II risk score.

AIMS: Inherited cardiomyopathies are relatively rare but carry a high risk of cardiac maternal morbidity and mortality during pregnancy and postpartum. However, data for risk stratification are scarce. The new CARPREG II score improves prediction of prognosis in pregnancies associated with heart disease, though its role in inherited cardiomyopathies is unclear. We aim to describe characteristics and cardiac maternal outcomes in patients with inherited cardiomyopathy during pregnancy, and to evaluate the interest of the CARPREG II risk score in this population. METHODS AND RESULTS: In this retrospective single-centre study, 90 consecutive pregnancies in 74 patients were included (mean age 32 ± 5 years), including 28 cases of dilated cardiomyopathy (DCM), 46 of hypertrophic cardiomyopathy, 11 of arrhythmogenic right ventricular cardiomyopathy and 5 of left ventricular noncompaction, excluding peripartum cardiomyopathy. The discriminatory power of several risk scores was assessed by the area under the receiver-operating characteristic curve (AUC). Median CARPREG II score was 2 [0;3] and was higher in the DCM subgroup. A severe cardiac maternal complication was observed in 18 (20%) pregnancies, mainly driven by arrhythmia and heart failure (each event in 10 pregnancies), with 3 cardiovascular deaths. Forty-three pregnancies (48%) presented foetal/neonatal complications (18 premature delivery, 3 foetal/neonatal death). CARPREG II was significantly associated with cardiac maternal complications (P < 0.05 for all) and showed a higher AUC (0.782) than CARPREG (0.755), mWHO (0.697) and ZAHARA (0.604). CONCLUSIONS: Pregnancy in women with inherited cardiomyopathy carries a high risk of maternal cardiovascular complications. CARPREG II is the most efficient predictor of cardiovascular complications in this population.

DNA-pools targeted-sequencing as a robust cost-effective method to detect rare variants: Application to dilated cardiomyopathy genetic diagnosis.

Dilated cardiomyopathy (DCM) is a heart disease characterized by left ventricular dilatation and systolic dysfunction. In 30% of cases, pathogenic variants, essentially private to each patient, are identified in at least one of almost 50 reported genes. Thus, while costly, exons capture-based Next Generation Sequencing (NGS) of a targeted gene panel appears as the best strategy to genetically diagnose DCM. Here, we report a NGS strategy applied to pools of 8 DNAs from DCM patients and validate its robustness for rare variants detection at 4-fold reduced cost. Our pipeline uses Freebayes to detect variants with the expected 1/16 allele frequency. From the whole set of detected rare variants in 96 pools we set the variants quality parameters optimizing true positives calling. When compared to simplex DNA sequencing in a shared subset of 50 DNAs, 96% of SNVs/InsDel were accurately identified in pools. Extended to the 384 DNAs included in the study, we detected 100 variants (ACMG class 4 and 5), mostly in well-known morbid gene causing DCM such as TTN, MYH7, FLNC, and TNNT2. To conclude, we report an original pool-sequencing NGS method accurately detecting rare variants. This innovative approach is cost-effective for genetic diagnostic in rare diseases.

Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide.

The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk.

Microbially Produced Imidazole Propionate Is Associated With Heart Failure and Mortality.

BACKGROUND: Over the past years, it has become clear that the microbial ecosystem in the gut has a profound capacity to interact with the host through the production of a wide range of bioactive metabolites. The microbially produced metabolite imidazole propionate (ImP) is clinically and mechanistically linked with insulin resistance and type 2 diabetes, but it is unclear how ImP is associated with heart failure. OBJECTIVES: The authors aimed to explore whether ImP is associated with heart failure and mortality. METHODS: ImP serum measurements in 2 large and independent clinical cohorts of patients (European [n = 1,985] and North American [n = 2,155]) with a range of severity of cardiovascular disease including heart failure. Univariate and multivariate Cox regression analyses were performed to delineate the impact of ImP on 5-year mortality in the North American cohort, independent of other covariates. RESULTS: ImP is independently associated with reduced ejection fraction and heart failure in both cohorts, even after adjusting for traditional risk factors. Elevated ImP was a significant independent predictor of 5-year mortality (for the highest quartile, adjusted HR: 1.85 [95% CI: 1.20-2.88]; P < 0.01). CONCLUSIONS: The gut microbial metabolite ImP is increased in individuals with heart failure and is a predictor of overall survival.

Feasibility and accuracy of linking a heart failure registry to the national claims database using indirect identifiers.

BACKGROUND: Heart failure (HF) registries include rich data on patient inclusion characteristics, but follow-up information is often incomplete. Medicoadministrative databases may provide less clinical information than registries, e.g. on left ventricular ejection fraction (LVEF), but long-term data are exhaustive and reliable. The combination of the two types of database is therefore appealing, but the feasibility and accuracy of such linking are largely unexplored. AIMS: To assess the feasibility and accuracy of linking an HF registry (FRESH; FREnch Survey on Heart Failure) with the French National Healthcare System database (SNDS). METHODS: A probabilistic algorithm was developed to link and match patient data included in the FRESH HF registry with anonymized records from the SNDS, which include: hospitalizations and diagnostic codes; all care-related reimbursements by national health system; and deaths. Consistency was assessed between deaths recorded in the registry and in the SNDS. A comparison between the two databases was carried out on several identifiable clinical characteristics (history of HF hospitalization, diabetes, atrial fibrillation, chronic bronchopneumopathy, severe renal failure and stroke) and on events during 1-year follow-up after inclusion. RESULTS: Of 2719 patients included in the FRESH registry (1049 during decompensation; 1670 during outpatient follow-up), 1885 could be matched with a high accuracy of 94.3% for deaths. Mortality curves were superimposable, including curves according to type of HF and LVEF. The rates of missing data in the FRESH registry were 2.3-8.4% for clinical characteristics and 17.5% for hospitalizations during follow-up. The discrepancy rate for clinical characteristics was 3-13%. Hospitalization rates were significantly higher in the SNDS than in the registry cohort. CONCLUSIONS: The anonymous matching of an HF research cohort with a national health database is feasible, with a significant proportion of patients being accurately matched, and facilitates combination of clinical data and a reduced rate of losses to follow-up.

Microbiome and metabolome features of the cardiometabolic disease spectrum.

Previous microbiome and metabolome analyses exploring non-communicable diseases have paid scant attention to major confounders of study outcomes, such as common, pre-morbid and co-morbid conditions, or polypharmacy. Here, in the context of ischemic heart disease (IHD), we used a study design that recapitulates disease initiation, escalation and response to treatment over time, mirroring a longitudinal study that would otherwise be difficult to perform given the protracted nature of IHD pathogenesis. We recruited 1,241 middle-aged Europeans, including healthy individuals, individuals with dysmetabolic morbidities (obesity and type 2 diabetes) but lacking overt IHD diagnosis and individuals with IHD at three distinct clinical stages-acute coronary syndrome, chronic IHD and IHD with heart failure-and characterized their phenome, gut metagenome and serum and urine metabolome. We found that about 75% of microbiome and metabolome features that distinguish individuals with IHD from healthy individuals after adjustment for effects of medication and lifestyle are present in individuals exhibiting dysmetabolism, suggesting that major alterations of the gut microbiome and metabolome might begin long before clinical onset of IHD. We further categorized microbiome and metabolome signatures related to prodromal dysmetabolism, specific to IHD in general or to each of its three subtypes or related to escalation or de-escalation of IHD. Discriminant analysis based on specific IHD microbiome and metabolome features could better differentiate individuals with IHD from healthy individuals or metabolically matched individuals as compared to the conventional risk markers, pointing to a pathophysiological relevance of these features.

Early and short-term intensive management after discharge for patients hospitalized with acute heart failure: a randomized study (ECAD-HF).

AIMS: Hospitalization for acute heart failure (HF) is followed by a vulnerable time with increased risk of readmission or death, thus requiring particular attention after discharge. In this study, we examined the impact of intensive, early follow-up among patients at high readmission risk at discharge after treatment for acute HF. METHODS AND RESULTS: Hospitalized acute HF patients were included with at least one of the following: previous acute HF < 6 months, systolic blood pressure ≤ 110 mmHg, creatininaemia ≥ 180 µmol/L, or B-type natriuretic peptide ≥ 350 pg/mL or N-terminal pro B-type natriuretic peptide ≥ 2200 pg/mL. Patients were randomized to either optimized care and education with serial consultations with HF specialist and dietician during the first 2-3 weeks, or to standard post-discharge care according to guidelines. The primary endpoint was all-cause death or first unplanned hospitalization during 6-month follow-up. Among 482 randomized patients (median age 77 and median left ventricular ejection fraction 35%), 224 were hospitalized or died. In the intensive group, loop diuretics (46%), beta-blockers (49%), angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (39%) and mineralocorticoid receptor antagonists (47%) were titrated. No difference was observed between groups for the primary endpoint (hazard ratio 0.97; 95% confidence interval 0.74-1.26), nor for mortality at 6 or 12 months or unplanned HF rehospitalization. Additionally, no difference between groups according to age, previous HF and left ventricular ejection fraction was found. CONCLUSIONS: In high-risk HF, intensive follow-up early post-discharge did not improve outcomes. This vulnerable post-discharge time requires further studies to clarify useful transitional care services.

Altered cardiac reserve is a determinant of exercise intolerance in sickle cell anaemia patients.

BACKGROUND: The underlying mechanisms of exercise intolerance in sickle cell anaemia (SCA) patients are complex and not yet completely understood. While latent heart failure at rest could be unmasked upon exercise, most previous studies assessed cardiac function at rest. We aimed to investigate exercise cardiovascular reserve as a potential contributor to exercise intolerance in adult SCA patients. METHODS: In this observational prospective study, we compared prospectively 60 SCA patients (median age 31 years, 60% women) to 20 matched controls. All subjects underwent symptom-limited combined exercise echocardiography and oxygen uptake (VO2 ) measurements. Differences between arterial and venous oxygen content (C(a-v)O2 ) were calculated. Cardiac reserve was defined as the absolute change in cardiac index (Ci) from baseline to peak exercise. RESULTS: Compared to controls, SCA patients demonstrated severe exercise intolerance (median peakVO2 , 34.3 vs. 19.7 ml/min/kg, respectively, p < .0001). SCA patients displayed heterogeneously increased Ci from rest to peak exercise (median +5.8, range 2.6 to 10.6 L/min/m²) which correlated with peakVO2 (r = 0.71, p < .0001). In contrast, the C(a-v)O2 exercise reserve was homogenously reduced and did not correlate with peakVO2 (r = 0.18, p = .16). While haemoglobin level and C(a-v)O2 were similar in SCA subgroups, SCA patients in the lower VO2 tertile had chronotropic incompetence and left ventricular diastolic dysfunction (left atrial peak longitudinal strain was reduced, and both E/e' ratio and left atrial volume index were increased) and were characterized by a reduced cardiac reserve, +5.0[4.2-5.5] compared to +6.7[5.5-7.8] L/min/m² for the rest of the patient cohort, p < .0001. CONCLUSIONS: Altered cardiac reserve due to chronotropic incompetence and left ventricular diastolic dysfunction seems to be an important determinant of exercise intolerance in adult SCA patients.

Combinatorial, additive and dose-dependent drug-microbiome associations.

During the transition from a healthy state to cardiometabolic disease, patients become heavily medicated, which leads to an increasingly aberrant gut microbiome and serum metabolome, and complicates biomarker discovery1-5. Here, through integrated multi-omics analyses of 2,173 European residents from the MetaCardis cohort, we show that the explanatory power of drugs for the variability in both host and gut microbiome features exceeds that of disease. We quantify inferred effects of single medications, their combinations as well as additive effects, and show that the latter shift the metabolome and microbiome towards a healthier state, exemplified in synergistic reduction in serum atherogenic lipoproteins by statins combined with aspirin, or enrichment of intestinal Roseburia by diuretic agents combined with beta-blockers. Several antibiotics exhibit a quantitative relationship between the number of courses prescribed and progression towards a microbiome state that is associated with the severity of cardiometabolic disease. We also report a relationship between cardiometabolic drug dosage, improvement in clinical markers and microbiome composition, supporting direct drug effects. Taken together, our computational framework and resulting resources enable the disentanglement of the effects of drugs and disease on host and microbiome features in multimedicated individuals. Furthermore, the robust signatures identified using our framework provide new hypotheses for drug-host-microbiome interactions in cardiometabolic disease.

Genome-wide association analysis in dilated cardiomyopathy reveals two new players in systolic heart failure on chromosomes 3p25.1 and 22q11.23.

AIMS: Our objective was to better understand the genetic bases of dilated cardiomyopathy (DCM), a leading cause of systolic heart failure. METHODS AND RESULTS: We conducted the largest genome-wide association study performed so far in DCM, with 2719 cases and 4440 controls in the discovery population. We identified and replicated two new DCM-associated loci on chromosome 3p25.1 [lead single-nucleotide polymorphism (SNP) rs62232870, P = 8.7 × 10-11 and 7.7 × 10-4 in the discovery and replication steps, respectively] and chromosome 22q11.23 (lead SNP rs7284877, P = 3.3 × 10-8 and 1.4 × 10-3 in the discovery and replication steps, respectively), while confirming two previously identified DCM loci on chromosomes 10 and 1, BAG3 and HSPB7. A genetic risk score constructed from the number of risk alleles at these four DCM loci revealed a 3-fold increased risk of DCM for individuals with 8 risk alleles compared to individuals with 5 risk alleles (median of the referral population). In silico annotation and functional 4C-sequencing analyses on iPSC-derived cardiomyocytes identify SLC6A6 as the most likely DCM gene at the 3p25.1 locus. This gene encodes a taurine transporter whose involvement in myocardial dysfunction and DCM is supported by numerous observations in humans and animals. At the 22q11.23 locus, in silico and data mining annotations, and to a lesser extent functional analysis, strongly suggest SMARCB1 as the candidate culprit gene. CONCLUSION: This study provides a better understanding of the genetic architecture of DCM and sheds light on novel biological pathways underlying heart failure.

Practical management of worsening renal function in outpatients with heart failure and reduced ejection fraction: Statement from a panel of multidisciplinary experts and the Heart Failure Working Group of the French Society of Cardiology.

Renal function is often affected in patients with chronic heart failure with reduced ejection fraction (HFrEF). The complex interplay between heart and renal dysfunction makes renal function and potassium monitoring mandatory. Renin-angiotensin-aldosterone system (RAAS) blockers are a life-saving treatment for patients with HFrEF, regardless of worsening renal function. Uptitration to the maximum-tolerated dose should be a constant goal. This simple fact is all too often forgotten (only 30% of patients with heart failure receive the target dosage of RAAS blockers), and the RAAS blocker effect on renal function is sometimes misunderstood. RAAS blockers are not nephrotoxic drugs as they only have a functional effect on renal function. In many routine clinical cases, RAAS blockers are withheld or stopped because of this misunderstanding, combined with suboptimal assessment of the clinical situation and underestimation of the life-saving effect of RAAS blockers despite worsening renal function. In this expert panel, which includes heart failure specialists, geriatricians and nephrologists, we propose therapeutic management algorithms for worsening renal function for physicians in charge of outpatients with chronic heart failure. Firstly, the essential variables to take into consideration before changing treatment are the presence of concomitant disorders that could alter renal function status (e.g. infection, diarrhoea, hyperthermia), congestion/dehydration status, blood pressure and intake of nephrotoxic drugs. Secondly, physicians are invited to adapt medication according to four clinical scenarios (patient with congestion, dehydration, hypotension or hyperkalaemia). Close biological monitoring after treatment modification is mandatory. We believe that this practical clinically minded management algorithm can help to optimize HFrEF treatment in routine clinical practice.

Significance of NT-proBNP and High-sensitivity Troponin in Friedreich Ataxia.

BACKGROUND: Friedreich's ataxia (FA) is a rare autosomal recessive mitochondrial disease resulting of a triplet repeat expansion guanine-adenine-adenine (GAA) in the frataxin (FXN) gene, exhibiting progressive cerebellar ataxia, diabetes and cardiomyopathy. We aimed to determine the relationship between cardiac biomarkers, serum N-terminal pro-brain natriuretic peptide (NT-proBNP), and serum cardiac high-sensitivity troponin (hsTnT) concentrations, and the extent of genetic abnormality and cardiac parameters. METHODS: Between 2013 and 2015, 85 consecutive genetically confirmed FA adult patients were prospectively evaluated by measuring plasma hsTnT and NT-proBNP concentrations, electrocardiogram, and echocardiography. RESULTS: The 85 FA patients (49% women) with a mean age of 39 ± 12 years, a mean disease onset of 17 ± 11 years had a mean SARA (Scale for the Assessment and Rating of Ataxia) score of 26 ± 10. The median hsTnT concentration was 10 ng/L (3 to 85 ng/L) and 34% had a significant elevated hsTnT ≥ 14 ng/L. Increased septal wall thickness was associated with increased hsTnT plasma levels (p < 0.001). The median NT-proBNP concentration was 31 ng/L (5 to 775 ng/L) and 14% had significant elevated NT-proBNP ≥ 125 ng/L. Markers of increased left ventricular filling pressure (trans mitral E/A and lateral E/E' ratio) were associated with increased NT-proBNP plasma levels (p = 0.01 and p = 0.01). Length of GAA or the SARA score were not associated with hsTnT or NT-proBNP plasma levels. CONCLUSION: hsTnT was increased in 1/3 of the adult FA and associated with increased septal wall thickness. Increased NT-proBNP remained a marker of increased left ventricular filling pressure. This could be used to identify patients that should undergo a closer cardiac surveillance.

Antithrombotic Therapy for Patients With Left Ventricular Mural Thrombus.

BACKGROUND: Contemporary data are lacking regarding the prognosis and management of left ventricular thrombus (LVT). OBJECTIVES: The purpose of this study was to quantify the effect of anticoagulation therapy on LVT evolution using sequential imaging and to determine the impact of LVT regression on the incidence of thromboembolism, bleeding, and mortality. METHODS: From January 2011 to January 2018, a comprehensive computerized search of LVT was conducted using 90,065 consecutive echocardiogram reports. Only patients with a confirmed LVT were included after imaging review by 2 independent experts. Major adverse cardiovascular events (MACE), which included death, stroke, myocardial infarction, or acute peripheral artery emboli, were determined as well as major bleeding events (BARC ≥3) and all-cause mortality rates. RESULTS: There were 159 patients with a confirmed LVT. Patients were treated with vitamin K antagonists (48.4%), parenteral heparins (27.7%), and direct oral anticoagulants (22.6%). Antiplatelet therapy was used in 67.9% of the population. A reduction of the LVT area from baseline was observed in 121 patients (76.1%), and total LVT regression occurred in 99 patients (62.3%) within a median time of 103 days (interquartile range: 32 to 392 days). The independent correlates of LVT regression were a nonischemic cardiomyopathy (hazard ratio [HR]: 2.74; 95% confidence interval [CI]: 1.43 to 5.26; p = 0.002) and a smaller baseline thrombus area (HR: 0.66; 95% CI: 0.45 to 0.96; p = 0.031). The frequency of MACE was 37.1%; mortality 18.9%; stroke 13.3%; and major bleeding 13.2% during a median follow-up of 632 days (interquartile range: 187 to 1,126 days). MACE occurred in 35.4% and 40.0% of patients with total LVT regression and those with persistent LVT (p = 0.203). A reduced risk of mortality was observed among patients with total LVT regression (HR: 0.48; 95% CI: 0.23 to 0.98; p = 0.039), whereas an increased major bleeding risk was observed among patients with persistent LVT (9.1% vs. 12%; HR 0.34; 95% CI: 0.14 to 0.82; p = 0.011). A left ventricular ejection fraction ≥35% (HR: 0.46; 95% CI: 0.23 to 0.93; p = 0.029) and anticoagulation therapy >3 months (HR: 0.42; 95% CI: 0.20 to 0.88; p = 0.021) were independently associated with less MACE. CONCLUSIONS: The presence of LVT was associated with a very high risk of MACE and mortality. Total LVT regression, obtained with different anticoagulant regimens, was associated with reduced mortality.

Correction: Exome-wide association study reveals novel susceptibility genes to sporadic dilated cardiomyopathy.

[This corrects the article DOI: 10.1371/journal.pone.0172995.].

Global and regional echocardiographic strain to assess the early phase of hypertrophic cardiomyopathy due to sarcomeric mutations.

AIMS: Hypertrophic cardiomyopathy (HCM) is a genetic disease with delayed cardiac expression. Our objective was to characterize left ventricular (LV) myocardial strain by two-dimensional echocardiography in sarcomeric mutation carriers before the hypertrophic stage. METHODS AND RESULTS: We studied 140 adults [derivation cohort (n = 79), validation cohort (n = 61)]. The derivation cohort comprised 38 confirmed HCM patients with hypertrophy (LVH+/Gen+), 20 mutation carriers without LV hypertrophy (LVH-/Gen+), and 21 healthy controls. LV global longitudinal strain was not different in LVH-/Gen+ compared with controls [20.6%, interquartile (IQ): 18.3/24.2 vs. 22.9%, IQ: 20.9/26.8] but was reduced in LVH+/Gen+ patients (14.1%, IQ: 11.8/18.5, P < 0.001). Regional peak longitudinal strain was significantly decreased in LVH-/Gen+ when compared with controls in four segments: basal anteroseptal (BAS) wall (P = 0.018), basal inferoseptal wall (P = 0.047), basal inferior wall (P = 0.006), and mid anteroseptal wall (P = 0.022). Receiver operating characteristic analysis identified that BAS strain <16.5% had a sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV, NPV) of 57%, 90%, 82%, and 67%, respectively, to differentiate LVH-/G+ patients from controls. Similarly, the accuracy of a ratio between basal inferoseptal/basal anterolateral (BIS/BAL) strain <0.76 was 73%, 92%, 82%, and 64%, respectively (Se/Sp/PPV/NPV). In the validation cohort, the accuracy of BAS and BIS/BAL was 39%/93%/87%/57% and 55%/96%/95%/64% (Se/Sp/PPV/NPV), respectively, to differentiate the LVH-/Gen+ group from controls. CONCLUSION: Regional longitudinal strain, but not global strain, was significantly reduced at the early stage of HCM before LV hypertrophy. This suggests that the inclusion of strain (BAS < 16.5%; BIS/BAL < 0.76) in the evaluation of HCM relatives would help identify mutation carriers and early LV abnormalities.

Mid-regional proatrial natriuretic peptide for predicting prognosis in hypertrophic cardiomyopathy.

OBJECTIVES: N-terminal probrain natriuretic peptide (NT-proBNP) predicts mortality and the development of heart failure in hypertrophic cardiomyopathy (HCM). Mid-regional proatrial natriuretic peptide (MR-proANP) is a stable by-product of production of atrial natriuretic peptide. We sought to compare the prognostic value of MR-proANP and NT-proBNP in HCM. METHODS: We prospectively enrolled a cohort of patients with HCM from different European centres and followed them. All patients had clinical, ECG and echocardiographic evaluation and measurement of MR-proANP and NT-proBNP at inclusion. RESULTS: Of 357 patients enrolled, the median age was 52 (IQR: 36-65) years. MR-proANP and NT-proBNP were both independently associated with age, weight, New York Heart Association (NYHA) class, left ventricular ejection fraction (LVEF), wall thickness and left atrial dimension. During a median follow-up of 23 months, 32 patients had a primary end point defined as death (n=6), heart transplantation (n=8), left ventricular assist device implantation (n=1) or heart failure hospitalisation (n=17). Both NT-proBNP and MR-proANP (p<10-4) were strongly associated with the primary endpoint, and the areas under the receiver operating characteristic (ROC) curves for both peptides were not significantly different. However, in a multiple stepwise regression analysis, the best model for predicting outcome was NYHA 1-2 vs 3-4 (HR=0.35, 95% CI 0.16 to 0.77, p<0.01), LVEF (HR=0.96, 95% CI 0.94 to 0.98, p=0.0005) and MR-proANP (HR=3.77, 95% CI 2.01 to 7.08, p<0.0001). CONCLUSIONS: MR-proANP emerges as a valuable biomarker for the prediction of death and heart failure related events in patients with HCM.