Left Atrial Function in Patients with Titin Cardiomyopathy.

BACKGROUND: Truncating variants in titin (TTNtv) are the most prevalent genetic etiology of dilated cardiomyopathy (DCM). Although TTNtv has been associated with atrial fibrillation, it remains unknown whether and how left atrial (LA) function differs between patients with DCM with and without TTNtv. We aimed to determine and compare LA function in patients with DCM with and without TTNtv and to evaluate whether and how left ventricular (LV) function affects the LA using computational modeling. METHODS AND RESULTS: Patients with DCM from the Maastricht DCM registry that underwent genetic testing and cardiovascular magnetic resonance (CMR) were included in the current study. Subsequent computational modeling (CircAdapt model) was performed to identify potential LV and LA myocardial hemodynamic substrates. In total, 377 patients with DCM (n = 42 with TTNtv, n = 335 without a genetic variant) were included (median age 55 years, interquartile range [IQR] 46-62 years, 62% men). Patients with TTNtv had a larger LA volume and decreased LA strain compared with patients without a genetic variant (LA volume index 60 mLm-2 [IQR 49-83] vs 51 mLm-2 [IQR 42-64]; LA reservoir strain 24% [IQR 10-29] vs 28% [IQR 20-34]; LA booster strain 9% [IQR 4-14] vs 14% [IQR 10-17], respectively; all P < .01). Computational modeling suggests that while the observed LV dysfunction partially explains the observed LA dysfunction in the patients with TTNtv, both intrinsic LV and LA dysfunction are present in patients with and without a TTNtv. CONCLUSIONS: Patients with DCM with TTNtv have more severe LA dysfunction compared with patients without a genetic variant. Insights from computational modeling suggest that both intrinsic LV and LA dysfunction are present in patients with DCM with and without TTNtv.

Papillary Muscle Delayed Hyperenhancement: Prevalence and Clinical Implications in a Large Population With Dilated Cardiomyopathy.

Background: Papillary muscle-delayed hyperenhancement (papHE) at cardiac magnetic resonance indicates fibrotic or infiltrative processes. Contrary to myocardial HE, the prevalence and prognostic implications of papHE in patients with nonischemic dilated cardiomyopathy are unclear. Objectives: The purpose of this study was to determine the prevalence of papHE and describe its association with adverse clinical outcomes. Methods: This prospective cohort study included 528 patients who underwent late gadolinium enhancement cardiac magnetic resonance. The primary outcomes were all-cause mortality, sudden cardiac death, life-threatening arrhythmia, and hospitalization for heart failure. Patients were allocated into 4 categories: the first without papHE and without myocardial HE, the second with papHE, the third with myocardial HE, and the fourth with papHE and myocardial HE. The hazards of the primary outcomes for each category were compared using multivariable Cox regression. Results: papHE was present in 131 patients (25%). The median follow-up duration was 6.1 years (IQR: 3.7-9.7 years). Isolated papHE and isolated myocardial HE were not significantly associated with any of the prespecified outcomes. Patients who had both myocardial HE and papHE were at an increased risk of all-cause mortality (HR: 2.33, 95% CI: 1.26-4.30), sudden cardiac death (HR: 3.77, 95% CI: 1.59-8.94), life-threatening arrhythmia (HR: 3.94, 95% CI: 1.34-11.58), and hospitalization for heart failure (HR: 2.97, 95% CI: 1.30-6.80). Conclusions: The combined presence of myocardial and papHE was independently associated with adverse outcomes. Future studies should investigate if the incorporation of papHE and myocardial HE may improve clinical decision-making strategies to select dilated cardiomyopathy patients who would benefit the most from ICD implantation.

Retinal Vascular Changes in Heart Failure with Preserved Ejection Fraction Using Optical Coherence Tomography Angiography.

Background: Systemic microvascular regression and dysfunction are considered important underlying mechanisms in heart failure with preserved ejection fraction (HFpEF), but retinal changes are unknown. Methods: This prospective study aimed to investigate whether retinal microvascular and structural parameters assessed using optical coherence tomography angiography (OCT-A) differ between patients with HFpEF and control individuals (i.e., capillary vessel density, thickness of retina layers). We also aimed to assess the associations of retinal parameters with clinical and echocardiographic parameters in HFpEF. HFpEF patients, but not controls, underwent echocardiography. Macula-centered 6 × 6 mm volume scans were computed of both eyes. Results: Twenty-two HFpEF patients and 24 controls without known HFpEF were evaluated, with an age of 74 [68-80] vs. 68 [58-77] years (p = 0.027), and 73% vs. 42% females (p = 0.034), respectively. HFpEF patients showed vascular degeneration compared to controls, depicted by lower macular vessel density (p < 0.001) and macular ganglion cell-inner plexiform layer thickness (p = 0.025), and a trend towards lower total retinal volume (p = 0.050) on OCT-A. In HFpEF, a lower total retinal volume was associated with markers of diastolic dysfunction (septal e', septal and average E/e': R2 = 0.38, 0.36, 0.25, respectively; all p < 0.05), even after adjustment for age, sex, diabetes mellitus, or atrial fibrillation. Conclusions: Patients with HFpEF showed clear levels of retinal vascular changes compared to control individuals, and retinal alterations appeared to be associated with markers of more severe diastolic dysfunction in HFpEF. OCT-A may therefore be a promising technique for monitoring systemic microvascular regression and cardiac diastolic dysfunction.

CMR-derived left ventricular intraventricular pressure gradients identify different patterns associated with prognosis in dilated cardiomyopathy.

AIMS: Left ventricular (LV) blood flow is determined by intraventricular pressure gradients (IVPG). Changes in blood flow initiate remodelling and precede functional decline. Novel cardiac magnetic resonance (CMR) post-processing LV-IVPG analysis might provide a sensitive marker of LV function in dilated cardiomyopathy (DCM). Therefore, the aim of our study was to evaluate LV-IVPG patterns and their prognostic value in DCM. METHODS AND RESULTS: LV-IVPGs between apex and base were measured on standard CMR cine images in DCM patients (n = 447) from the Maastricht Cardiomyopathy registry. Major adverse cardiovascular events, including heart failure hospitalisations, life-threatening arrhythmias, and sudden/cardiac death, occurred in 66 DCM patients (15%). A temporary LV-IVPG reversal during systolic-diastolic transition, leading to a prolonged transition period or slower filling, was present in 168 patients (38%). In 14%, this led to a reversal of blood flow, which predicted outcome corrected for univariable predictors [hazard ratio (HR) = 2.57, 95% confidence interval (1.01-6.51), P = 0.047]. In patients without pressure reversal (n = 279), impaired overall LV-IVPG [HR = 0.91 (0.83-0.99), P = 0.033], systolic ejection force [HR = 0.91 (0.86-0.96), P < 0.001], and E-wave decelerative force [HR = 0.83 (0.73-0.94), P = 0.003] predicted outcome, independent of known predictors (age, sex, New York Heart Association class ≥ 3, LV ejection fraction, late gadolinium enhancement, LV-longitudinal strain, left atrium (LA) volume-index, and LA-conduit strain). CONCLUSION: Pressure reversal during systolic-diastolic transition was observed in one-third of DCM patients, and reversal of blood flow direction predicted worse outcome. In the absence of pressure reversal, lower systolic ejection force, E-wave decelerative force (end of passive LV filling), and overall LV-IVPG are powerful predictors of outcome, independent of clinical and imaging parameters.

Biomarkers of Collagen Metabolism Are Associated with Left Ventricular Function and Prognosis in Dilated Cardiomyopathy: A Multi-Modal Study.

BACKGROUND: Collagen cross-linking is a fundamental process in dilated cardiomyopathy (DCM) and occurs when collagen deposition exceeds degradation, leading to impaired prognosis. This study investigated the associations of collagen-metabolism biomarkers with left ventricular function and prognosis in DCM. METHODS: DCM patients who underwent endomyocardial biopsy, blood sampling, and cardiac MRI were included. The primary endpoint included death, heart failure hospitalization, or life-threatening arrhythmias, with a follow-up of 6 years (5-8). RESULTS: In total, 209 DCM patients were included (aged 54 ± 13 years, 65% male). No associations were observed between collagen volume fraction, circulating carboxy-terminal propeptide of procollagen type-I (PICP), or collagen type I carboxy-terminal telopeptide [CITP] and matrix metalloproteinase [MMP]-1 ratio and cardiac function parameters. However, CITP:MMP-1 was significantly correlated with global longitudinal strain (GLS) in the total study sample (R = -0.40, p < 0.0001; lower CITP:MMP-1 ratio was associated with impaired GLS), with even stronger correlations in patients with LVEF > 40% (R = -0.70, p < 0.0001). Forty-seven (22%) patients reached the primary endpoint. Higher MMP-1 levels were associated with a worse outcome, even after adjustment for clinical and imaging predictors (1.026, 95% CI 1.002-1.051, p = 0.037), but CITP and CITP:MMP-1 were not. Combining MMP-1 and PICP improved the goodness-of-fit (LHR36.67, p = 0.004). CONCLUSION: The degree of myocardial cross-linking (CITP:MMP-1) is associated with myocardial longitudinal contraction, and MMP-1 is an independent predictor of outcome in DCM patients.

Clustering of Cardiac Transcriptome Profiles Reveals Unique: Subgroups of Dilated Cardiomyopathy Patients.

Dilated cardiomyopathy is a heterogeneous disease characterized by multiple genetic and environmental etiologies. The majority of patients are treated the same despite these differences. The cardiac transcriptome provides information on the patient's pathophysiology, which allows targeted therapy. Using clustering techniques on data from the genotype, phenotype, and cardiac transcriptome of patients with early- and end-stage dilated cardiomyopathy, more homogeneous patient subgroups are identified based on shared underlying pathophysiology. Distinct patient subgroups are identified based on differences in protein quality control, cardiac metabolism, cardiomyocyte function, and inflammatory pathways. The identified pathways have the potential to guide future treatment and individualize patient care.

Clonal Hematopoiesis Has Prognostic Value in Dilated Cardiomyopathy Independent of Age and Clone Size.

BACKGROUND: Clonal hematopoiesis (CH) gives rise to mutated leukocyte clones that induce cardiovascular inflammation and thereby impact the disease course in atherosclerosis and ischemic heart failure. CH of indeterminate potential refers to a variant allele frequency (VAF; a marker for clone size) in blood of ≥2%. The impact of CH clones-including small clone sizes (VAF <0.5%)-in nonischemic dilated cardiomyopathy (DCM) remains largely undetermined. OBJECTIVES: The authors sought to establish the prognostic impact of CH in DCM including small clones. METHODS: CH is determined using an ultrasensitive single-molecule molecular inversion probe technique that allows detection of clones down to a VAF of 0.01%. Cardiac death and all-cause mortality were analyzed using receiver-operating characteristic curve-optimized VAF cutoff values. RESULTS: A total of 520 DCM patients have been included. One hundred and nine patients (21%) had CH driver mutations, of which 45 had a VAF of ≥2% and 31 <0.5%. The median follow-up duration was 6.5 years [IQR: 4.7-9.7 years]. DCM patients with CH have a higher risk of cardiac death (HR: 2.33 using a VAF cutoff of 0.36%, 95% CI: 1.24-4.40) and all-cause mortality (HR: 1.72 using a VAF cutoff of 0.06%, 95% CI: 1.10-2.69), independent of age, sex, left ventricular ejection fraction, and New York Heart Association classification. CONCLUSIONS: CH predicts cardiac death and all-cause mortality in DCM patients with optimal thresholds for clone size of 0.36% and 0.06%, respectively. Therefore, CH is prognostically relevant, independent of clone size in patients with DCM.

Prevalence and Clinical Consequences of Multiple Pathogenic Variants in Dilated Cardiomyopathy.

BACKGROUND: Dilated cardiomyopathy (DCM) was considered a monogenetic disease that can be caused by over 60 genes. Evidence suggests that the combination of multiple pathogenic variants leads to greater disease severity and earlier onset. So far, not much is known about the prevalence and disease course of multiple pathogenic variants in patients with DCM. To gain insight into these knowledge gaps, we (1) systematically collected clinical information from a well-characterized DCM cohort and (2) created a mouse model. METHODS: Complete cardiac phenotyping and genotyping was performed in 685 patients with consecutive DCM. Compound heterozygous digenic (LMNA [lamin]/titin deletion A-band) with monogenic (LMNA/wild-type) and wild-type/wild-type mice were created and phenotypically followed over time. RESULTS: One hundred thirty-one likely pathogenic/pathogenic (LP/P) variants in robust DCM-associated genes were found in 685 patients with DCM (19.1%) genotyped for the robust genes. Three of the 131 patients had a second LP/P variant (2.3%). These 3 patients had a comparable disease onset, disease severity, and clinical course to patients with DCM with one LP/P. The LMNA/Titin deletion A-band mice had no functional differences compared with the LMNA/wild-type mice after 40 weeks of follow-up, although RNA-sequencing suggests increased cardiac stress and sarcomere insufficiency in the LMNA/Titin deletion A-band mice. CONCLUSIONS: In this study population, 2.3% of patients with DCM with one LP/P also have a second LP/P in a different gene. Although the second LP/P does not seem to influence the disease course of DCM in patients and mice, the finding of a second LP/P can be of importance to their relatives.

Comprehensive Cardiovascular Magnetic Resonance-Derived Myocardial Strain Analysis Provides Independent Prognostic Value in Acute Myocarditis.

Background Late gadolinium enhancement and left ventricular (LV) ejection fraction on cardiovascular magnetic resonance (CMR) are prognostic markers, but their predictive value for incident heart failure or life-threatening arrhythmias in acute myocarditis patients is limited. CMR-derived feature tracking provides a more sensitive analysis of myocardial function and may improve risk stratification in myocarditis. In this study, the prognostic value of LV, right ventricular, and left atrial strain in acute myocarditis patients is evaluated. Methods and Results In this multicenter retrospective study, patients with CMR-proven acute myocarditis were included. The primary end point was occurrence of major adverse cardiovascular events: all-cause mortality, heart transplantation, heart failure hospitalizations, and life threatening arrhythmias. LV global longitudinal strain, global circumferential strain and global radial strain, right ventricular-global longitudinal strain and left atrial strain were measured. Unadjusted and adjusted cox proportional hazard regression analysis were performed. In total, 162 CMR-proven myocarditis patients were included (41 ± 17 years, 75% men). Mean LV ejection fraction was 51 ± 12%, and 144 (89%) patients had presence of late gadolinium enhancement. Major adverse cardiovascular events occurred in 29 (18%) patients during a follow-up of 5.5 (2.2-8.3) years. All LV strain parameters were independent predictors of outcome beyond clinical features, LV ejection fraction and late gadolinium enhancement (LV-global longitudinal strain: hazard ratio [HR] 1.07, P=0.02; LV-global circumferential strain: HR 1.15, P=0.02; LV-global radial strain: HR 0.98, P=0.03), but right ventricular or left atrial strain did not predict outcome. Conclusions CMR-derived LV strain analysis provides independent prognostic value on top of clinical parameters, LV ejection fraction and late gadolinium enhancement in acute myocarditis patients, while left atrial and right ventricular strain seem to be of less importance.

Left Atrial Strain Has Superior Prognostic Value to Ventricular Function and Delayed-Enhancement in Dilated Cardiomyopathy.

BACKGROUND: The left atrium is an early sensor of left ventricular (LV) dysfunction. Still, the prognostic value of left atrial (LA) function (strain) on cardiac magnetic resonance (CMR) in dilated cardiomyopathy (DCM) remains unknown. OBJECTIVES: The goal of this study was to evaluate the prognostic value of CMR-derived LA strain in DCM. METHODS: Patients with DCM from the Maastricht Cardiomyopathy Registry with available CMR imaging were included. The primary endpoint was the combination of sudden or cardiac death, heart failure (HF) hospitalization, or life-threatening arrhythmias. Given the nonlinearity of continuous variables, cubic spline analysis was performed to dichotomize. RESULTS: A total of 488 patients with DCM were included (median age: 54 [IQR: 46-62] years; 61% male). Seventy patients (14%) reached the primary endpoint (median follow-up: 6 [IQR: 4-9] years). Age, New York Heart Association (NYHA) functional class >II, presence of late gadolinium enhancement (LGE), LV ejection fraction (LVEF), LA volume index (LAVI), LV global longitudinal strain (GLS), and LA reservoir and conduit strain were univariably associated with the outcome (all P < 0.02). LA conduit strain was a stronger predictor of outcome compared with reservoir strain. LA conduit strain, NYHA functional class >II, and LGE remained associated in the multivariable model (LA conduit strain HR: 3.65 [95% CI: 2.01-6.64; P < 0.001]; NYHA functional class >II HR: 1.81 [95% CI: 1.05-3.12; P = 0.033]; and LGE HR: 2.33 [95% CI: 1.42-3.85; P < 0.001]), whereas age, N-terminal pro-B-type natriuretic peptide, LVEF, left atrial ejection fraction, LAVI, and LV GLS were not. Adding LA conduit strain to other independent predictors (NYHA functional class and LGE) significantly improved the calibration, accuracy, and reclassification of the prediction model (P < 0.05). CONCLUSIONS: LA conduit strain on CMR is a strong independent prognostic predictor in DCM, superior to LV GLS, LVEF, and LAVI and incremental to LGE. Including LA conduit strain in DCM patient management should be considered to improve risk stratification.

Global Longitudinal Strain is Incremental to Left Ventricular Ejection Fraction for the Prediction of Outcome in Optimally Treated Dilated Cardiomyopathy Patients.

Background Speckle tracking echocardiographic global longitudinal strain (GLS) predicts outcome in patients with new onset heart failure. Still, its incremental value on top of left ventricular ejection fraction (LVEF) in patients with nonischemic, nonvalvular dilated cardiomyopathy (DCM) after optimal heart failure treatment remains unknown. Methods and Results Patients with DCM were included at the outpatient clinics of 2 centers in the Netherlands and Italy. The prognostic value of 2-dimensional speckle tracking echocardiographic global longitudinal strain was evaluated when being on optimal heart failure medication for at least 6 months. Outcome was defined as the combination of sudden or cardiac death, life-threatening arrhythmias, and heart failure hospitalization. A total of 323 patients with DCM (66% men, age 55±14 years) were included. The mean LVEF was 42%±11% and mean GLS after optimal heart failure treatment was -15%±4%. Twenty percent (64/323) of all patients reached the primary outcome after optimal heart failure treatment (median follow-up of 6[4-9] years). New York Heart Association class ≥3, LVEF, and GLS remained associated with the outcome in the multivariable-adjusted model (New York Heart Association class: hazard ratio [HR], 3.43; 95% CI, 1.49-7.90, P=0.004; LVEF: HR, 2.13; 95% CI, 1.11-4.10, P=0.024; GLS: HR, 2.24; 95% CI, 1.18-4.29, P=0.015), whereas left ventricular end-diastolic diameter index, left atrial volume index, and delta GLS were not. The addition of GLS to New York Heart Association class and LVEF improved the goodness of fit (log likelihood ratio test P<0.001) and discrimination (Harrell's C 0.703). Conclusions Within this bicenter study, GLS emerged as an independent and incremental predictor of adverse outcome, which exceeded LVEF in patients with optimally treated DCM. This presses the need to routinely include GLS in the echocardiographic follow-up of DCM.

Cardiovascular outcome 6 months after severe coronavirus disease 2019 infection.

OBJECTIVES: In coronavirus disease 2019 (COVID-19), cardiovascular risk factors and myocardial injury relate to increased mortality. We evaluated the extent of cardiac sequelae 6 months after hospital discharge in patients surviving ICU hospitalization for COVID-19. METHODS: All survivors of Maastricht-ICU were invited for comprehensive cardiovascular evaluation 6 months after discharge from ICU. Cardiac screening included an electrocardiogram, cardiac biomarkers, echocardiography, cardiac magnetic resonance (CMR) and, wherever indicated, cardiac computed tomography or coronary angiogram. RESULTS: Out of 52 survivors, 81% ( n  = 42) participated to the cardiovascular follow-up [median follow-up of 6 months, interquartile range (IQR) 6.1-6.7]. Eight patients (19%) had newly diagnosed coronary artery disease (CAD), of which two required a percutaneous intervention. Echocardiographic global longitudinal strain (GLS) was abnormal in 24% and CMR-derived GLS was abnormal in 12%, despite normal left ventricular ejection fraction in all. None of the patients showed elevated T 1 relaxation times and five patients (14%) had an elevated T 2 relaxation time. Late gadolinium enhancement (LGE) reflecting regional myocardial fibrosis was increased in eight patients (21%), of which three had myocarditis and three had pericarditis. CONCLUSION: Cardiovascular follow-up at 6 months after ICU-admission for severe COVID-19 revealed that one out of five invasively mechanically ventilated survivors had CAD, a quarter had subclinical left ventricular dysfunction defined as reduced echocardiographic GLS, and 42% of the patients had CMR abnormalities (reduced LVEF, reduced GLS, LGE presence, and elevated T 2 ). On the basis of these findings, long-term cardiovascular follow-up is strongly recommended in all post-IC COVID-19 patients. CLINICAL TRIAL REGISTRATION: Trial Register number [NL8613]) https://www.trialregister.nl/trial/8613Video abstract:http://links.lww.com/HJH/B899 .

Interatrial Block Predicts Life-Threatening Arrhythmias in Dilated Cardiomyopathy.

Background Interatrial block (IAB) has been associated with supraventricular arrhythmias and stroke, and even with sudden cardiac death in the general population. Whether IAB is associated with life-threatening arrhythmias (LTA) and sudden cardiac death in dilated cardiomyopathy (DCM) remains unknown. This study aimed to determine the association between IAB and LTA in ambulant patients with DCM. Methods and Results A derivation cohort (Maastricht Dilated Cardiomyopathy Registry; N=469) and an external validation cohort (Utrecht Cardiomyopathy Cohort; N=321) were used for this study. The presence of IAB (P-wave duration>120 milliseconds) or atrial fibrillation (AF) was determined using digital calipers by physicians blinded to the study data. In the derivation cohort, IAB and AF were present in 291 (62%) and 70 (15%) patients with DCM, respectively. LTA (defined as sudden cardiac death, justified shock from implantable cardioverter-defibrillator or anti-tachypacing, or hemodynamic unstable ventricular fibrillation/tachycardia) occurred in 49 patients (3 with no IAB, 35 with IAB, and 11 patients with AF, respectively; median follow-up, 4.4 years [2.1; 7.4]). The LTA-free survival distribution significantly differed between IAB or AF versus no IAB (both P<0.01), but not between IAB versus AF (P=0.999). This association remained statistically significant in the multivariable model (IAB: HR, 4.8 (1.4-16.1), P=0.013; AF: HR, 6.4 (1.7-24.0), P=0.007). In the external validation cohort, the survival distribution was also significantly worse for IAB or AF versus no IAB (P=0.037; P=0.005), but not for IAB versus AF (P=0.836). Conclusions IAB is an easy to assess, widely applicable marker associated with LTA in DCM. IAB and AF seem to confer similar risk of LTA. Further research on IAB in DCM, and on the management of IAB in DCM is warranted.

Improving diagnosis and risk stratification across the ejection fraction spectrum: the Maastricht Cardiomyopathy registry.

AIMS: Heart failure (HF) represents a clinical syndrome resulting from different aetiologies and degrees of heart diseases. Among these, a key role is played by primary heart muscle disease (cardiomyopathies), which are the combination of multifactorial environmental insults in the presence or absence of a known genetic predisposition. The aim of the Maastricht Cardiomyopathy registry (mCMP-registry; NCT04976348) is to improve (early) diagnosis, risk stratification, and management of cardiomyopathy phenotypes beyond the limits of left ventricular ejection fraction (LVEF). METHODS AND RESULTS: The mCMP-registry is an investigator-initiated prospective registry including patient characteristics, diagnostic measurements performed as part of routine clinical care, treatment information, sequential biobanking, quality of life and economic impact assessment, and regular follow-up. All subjects aged ≥16 years referred to the cardiology department of the Maastricht University Medical Center (MUMC+) for HF-like symptoms or cardiac screening for cardiomyopathies are eligible for inclusion, irrespective of phenotype or underlying causes. Informed consented subjects will be followed up for 15 years. Two central approaches will be used to answer the research questions related to the aims of this registry: (i) a data-driven approach to predict clinical outcome and response to therapy and to identify clusters of patients who share underlying pathophysiological processes; and (ii) a hypothesis-driven approach in which clinical parameters are tested for their (incremental) diagnostic, prognostic, or therapeutic value. The study allows other centres to easily join this initiative, which will further boost research within this field. CONCLUSIONS: The broad inclusion criteria, systematic routine clinical care data-collection, extensive study-related data-collection, sequential biobanking, and multi-disciplinary approach gives the mCMP-registry a unique opportunity to improve diagnosis, risk stratification, and management of HF and (early) cardiomyopathy phenotypes beyond the LVEF limits.

A global longitudinal strain cut-off value to predict adverse outcomes in individuals with a normal ejection fraction.

AIMS: Global longitudinal strain (GLS) has become an alternative to left ventricular ejection fraction (LVEF) to determine systolic function of the heart. The absence of cut-off values is one of the limitations preventing full clinical implementation. The aim of this study is to determine a cut-off value of GLS for an increased risk of adverse events in individuals with a normal LVEF. METHODS AND RESULTS: Echocardiographic images of 502 subjects (52% female, mean age 48 ± 15) with an LVEF ≥ 55% were analysed using speckle tracking-based GLS. The primary endpoint was cardiovascular death or cardiac hospitalization. The analysis of Cox models with splines was performed to visualize the effect of GLS on outcome. A cut-off value was suggested by determining the optimal specificity and sensitivity. The median GLS was -22.2% (inter-quartile range -20.0 to -24.9%). In total, 35 subjects (7%) had a cardiac hospitalization and/or died because of cardiovascular disease during a follow-up of 40 (5-80) months. There was a linear correlation between the risk for adverse events and GLS value. Subjects with a normal LVEF and a GLS between -22.9% and -20.9% had a mildly increased risk (hazard ratio 1.01-2.0) for cardiac hospitalization or cardiovascular mortality, and the risk was doubled for subjects with a GLS of -20.9% and higher. The optimal specificity and sensitivity were determined at a GLS value of -20.0% (hazard ratio 2.49; 95% confidence interval: 1.71-3.61). CONCLUSIONS: There is a strong correlation between cardiac adverse events and GLS values in subjects with a normal LVEF. In our single-centre study, -20.0% was determined as a cut-off value to identify subjects at risk. A next step should be to integrate GLS values in a multi-parametric model.

Intravenous immunoglobulin therapy in adult patients with idiopathic chronic cardiomyopathy and cardiac parvovirus B19 persistence: a prospective, double-blind, randomized, placebo-controlled clinical trial.

AIMS: Previous uncontrolled studies suggested a possible benefit of intravenous immunoglobulin (IVIg) in parvovirus B19 (B19V)-related dilated cardiomyopathy (DCM). This randomized, double-blind, placebo-controlled, single-centre trial investigated the benefits of IVIg beyond conventional therapy in idiopathic chronic DCM patients with B19V persistence. METHODS AND RESULTS: Fifty patients (39 men; mean age 54 ± 11 years) with idiopathic chronic (>6 months) DCM on optimal medical therapy, left ventricular ejection fraction (LVEF) <45%, and endomyocardial biopsy (EMB) B19V load of >200 copies/µg DNA were blindly randomized to either IVIg (n = 26, 2 g/kg over 4 days) or placebo (n = 24). The primary outcome was change in LVEF at 6 months after randomization. Secondary outcomes were change in functional capacity assessed by 6-min walk test (6MWT), quality of life [Minnesota Living with Heart Failure Questionnaire (MLHFQ)], left ventricular end-diastolic volume (LVEDV), and EMB B19V load at 6 months after randomization. LVEF significantly improved in both IVIg and placebo groups (absolute mean increase 5 ± 9%, P = 0.011 and 6 ± 10%, P = 0.008, respectively), without a significant difference between groups (P = 0.609). Additionally, change in 6MWT [median (interquartile range) IVIg 36 (13;82) vs. placebo 32 (5;80) m; P = 0.573], MLHFQ [IVIg 0 (-7;5) vs. placebo -2 (-6;6), P = 0.904] and LVEDV (IVIg -16 ± 49 mL/m2 vs. placebo -29 ± 40 mL/m2 ; P = 0.334) did not significantly differ between groups. Moreover, despite increased circulating B19V antibodies upon IVIg administration, reduction in cardiac B19V did not significantly differ between groups. CONCLUSION: Intravenous immunoglobulin therapy does not significantly improve cardiac systolic function or functional capacity beyond standard medical therapy in patients with idiopathic chronic DCM and cardiac B19V persistence. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov ID NCT00892112.

The combination of carboxy-terminal propeptide of procollagen type I blood levels and late gadolinium enhancement at cardiac magnetic resonance provides additional prognostic information in idiopathic dilated cardiomyopathy - A multilevel assessment of myocardial fibrosis in dilated cardiomyopathy.

AIMS: To determine the prognostic value of multilevel assessment of fibrosis in dilated cardiomyopathy (DCM) patients. METHODS AND RESULTS: We quantified fibrosis in 209 DCM patients at three levels: (i) non-invasive late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR); (ii) blood biomarkers [amino-terminal propeptide of procollagen type III (PIIINP) and carboxy-terminal propeptide of procollagen type I (PICP)], (iii) invasive endomyocardial biopsy (EMB) (collagen volume fraction, CVF). Both LGE and elevated blood PICP levels, but neither PIIINP nor CVF predicted a worse outcome defined as death, heart transplantation, heart failure hospitalization, or life-threatening arrhythmias, after adjusting for known clinical predictors [adjusted hazard ratios: LGE 3.54, 95% confidence interval (CI) 1.90-6.60; P < 0.001 and PICP 1.02, 95% CI 1.01-1.03; P = 0.001]. The combination of LGE and PICP provided the highest prognostic benefit in prediction (likelihood ratio test P = 0.007) and reclassification (net reclassification index: 0.28, P = 0.02; and integrated discrimination improvement index: 0.139, P = 0.01) when added to the clinical prediction model. Moreover, patients with a combination of LGE and elevated PICP (LGE+/PICP+) had the worst prognosis (log-rank P < 0.001). RNA-sequencing and gene enrichment analysis of EMB showed an increased expression of pro-fibrotic and pro-inflammatory pathways in patients with high levels of fibrosis (LGE+/PICP+) compared to patients with low levels of fibrosis (LGE-/PICP-). This would suggest the validity of myocardial fibrosis detection by LGE and PICP, as the subsequent generated fibrotic risk profiles are associated with distinct cardiac transcriptomic profiles. CONCLUSION: The combination of myocardial fibrosis at CMR and circulating PICP levels provides additive prognostic value accompanied by a pro-fibrotic and pro-inflammatory transcriptomic profile in DCM patients with LGE and elevated PICP.

Contemporary use of devices in chronic heart failure in the Netherlands.

AIMS: Despite previous surveys regarding device implantation rates in heart failure (HF), insight into the real-world management with devices is scarce. Therefore, we investigated device implantation rates in HF with reduced left ventricular ejection fraction (LVEF) in 34 Dutch centres. METHODS AND RESULTS: A cross-sectional outpatient registry was conducted in 6666 patients with LVEF < 50% and with information about device implantation available [74 (66-81) years of age; 64% male]. Patients were classified into conventional pacemakers (PM, n = 562), implantable cardioverter defibrillators (ICD, n = 1165), and cardiac resynchronization therapy with defibrillator function (CRT-D, n = 885) or pacemaker function only (CRT-P, n = 248), or no device (n = 3806). Centres were divided into ICD-implanting and CRT-implanting and referral centres. Overall, 17.5% had an ICD, 13.3% CRT-D, 3.7% CRT-P, and 8.4% PM. Of those with LVEF ≤ 30%, 42.5% had ICD or CRT-D therapy. A large variation in implantation rates existed between centres: 3-51% for ICD therapy, 0.3-44% for CRT-D therapy, 0-11% for CRT-P therapy, and 0-25% PM therapy. Implantation centres showed higher implantation rates of ICD, CRT-D, and CRT-P compared with referral centres [36% vs. 25% for defibrillators (ICD or CRT-D) and 17% vs. 9% for CRT devices (CRT-D or CRT-P), respectively, P < 0.001], independently of other factors. A large number of clinical factors were predictive for device usage. Among other, LVEF < 40% and male sex were independent positive predictors for ICD/CRT-D use [odds ratio (OR) = 3.33, P < 0.001; OR = 1.87, P = 0.019, respectively]. Older age was independently associated with less ICD/CRT-D (OR = 0.96 per year, P < 0.001) and more CRT-P/PM use (OR = 1.03 per year, P = 0.006). CONCLUSIONS: In this large Dutch HF registry, less than half of the patients with reduced LVEF received an ICD or CRT, even if LVEF was ≤30%, and a large variation between centres existed. Patients from implantation centres had more often ICD or CRT. More uniformity regarding guideline-based use of device therapy in clinical practice is needed.

Risk of bias in studies investigating novel diagnostic biomarkers for heart failure with preserved ejection fraction. A systematic review.

AIM: Diagnosing heart failure with preserved ejection fraction (HFpEF) in the non-acute setting remains challenging. Natriuretic peptides have limited value for this purpose, and a multitude of studies investigating novel diagnostic circulating biomarkers have not resulted in their implementation. This review aims to provide an overview of studies investigating novel circulating biomarkers for the diagnosis of HFpEF and determine their risk of bias (ROB). METHODS AND RESULTS: A systematic literature search for studies investigating novel diagnostic HFpEF circulating biomarkers in humans was performed up until 21 April 2020. Those without diagnostic performance measures reported, or performed in an acute heart failure population were excluded, leading to a total of 28 studies. For each study, four reviewers determined the ROB within the QUADAS-2 domains: patient selection, index test, reference standard, and flow and timing. At least one domain with a high ROB was present in all studies. Use of case-control/two-gated designs, exclusion of difficult-to-diagnose patients, absence of a pre-specified cut-off value for the index test without the performance of external validation, the use of inappropriate reference standards and unclear timing of the index test and/or reference standard were the main bias determinants. Due to the high ROB and different patient populations, no meta-analysis was performed. CONCLUSION: The majority of current diagnostic HFpEF biomarker studies have a high ROB, reducing the reproducibility and the potential for clinical care. Methodological well-designed studies with a uniform reference diagnosis are urgently needed to determine the incremental value of circulating biomarkers for the diagnosis of HFpEF.