Left ventricular global longitudinal strain (LV-GLS) shows promise as a marker to detect early heart failure (HF). This study sought to (i) establish cardiac magnetic resonance imaging (CMR)–derived LV-GLS cut-offs to differentiate healthy from HF for both acquisition-based and post-processing techniques, (ii) assess agreement, and (iii) provide a method to convert LV-GLS between both techniques. A secondary analysis of a prospective study enrolling healthy subjects (n = 19) and HF patients (n = 56) was conducted. LV-GLS was measured using fast strain–encoded imaging (fSENC) and feature tracking (FT). Receiver operating characteristic (ROC) analyses were performed to derive and evaluate LV-GLS cut-offs discriminating between healthy, HF with mild deformation impairment (DI), and HF with severe DI. Linear regression and Bland–Altman analyses assessed agreement. Cut-offs discriminating between healthy and HF were identified at −19.3% and −15.1% for fSENC and FT, respectively. Cut-offs of −15.8% (fSENC) and −10.8% (FT) further distinguished mild from severe DI. No significant differences in area under ROC curve were identified between fSENC and FT. Bland–Altman analysis revealed a bias of −4.01%, 95% CI −4.42, −3.50 for FT, considering fSENC as reference. Linear regression suggested a factor of 0.76 to rescale fSENC-derived LV-GLS to FT. Using this factor on fSENC-derived cut-offs yielded rescaled FT LV-GLS cut-offs of −14.7% (healthy vs. HF) and −12% (mild vs. severe DI). LV-GLS distinguishes healthy from HF with high accuracy. Each measurement technique requires distinct cut-offs, but rescaling factors facilitate conversion. An FT-based LV-GLS ≥ −15% simplifies HF detection in clinical routine.

Cardiac magnetic resonance (CMR) T1 relaxation time mapping is an established technique primarily used to identify diffuse interstitial fibrosis and oedema. The myocardial extracellular volume (ECV) can be calculated from pre- and post-contrast T1 relaxation times and is a reproducible parametric index of the proportion of volume occupied by non-cardiomyocyte components in myocardial tissue. The conventional calculation of the ECV requires blood sampling to measure the haematocrit (HCT). Given the high variability of the HCT, the blood collection is recommended within 24 h of the CMR scan, limiting its applicability and posing a barrier to the clinical routine use of ECV measurements. In recent years, several research groups have proposed a method to determine the ECV by CMR without blood sampling. This is based on the inverse relationship between the T1 relaxation rate (R1) of blood and the HCT. Consequently, a ‘synthetic’ HCT could be estimated from the native blood R1, avoiding blood sampling. We performed a review and meta-analysis of published studies on synthetic ECV, as well as a secondary analysis of previously published data to examine the effect of the chosen regression modell on bias. While, overall, a good correlation and little bias between synthetic and conventional ECV were found in these studies, questions regarding its accuracy remain. Synthetic HCT and ECV can provide a ‘non-invasive’ quantitative measurement of the myocardium’s extracellular space when timely HCT measurements are not available and large alterations in ECV are expected, such as in cardiac amyloidosis. Due to the dependency of T1 relaxation times on the local setup, calculation of local formulas using linear regression is recommended, which can be easily performed using available data. For the establishment of a local model, ∼500 patients with measured haematocrit (HCT) and left ventricular T1 relaxation rate (R1 = 1/T1) should be available and split evenly into derivation and validation data sets. The regression parameters from the derivation data is used for the estimation of synthetic HCT, which is then used for the calculation of the synthetic extracellular volume (ECV) instead of the measured HCT.

BACKGROUND: There is a growing consensus that screening for subclinical preheart failure (HF) may reduce the burden of symptomatic HF by allowing for timely preventive interventions. However, validated screening algorithms are currently lacking. The aim of this study was to evaluate a fully mobile telemedically supervised cardiac magnetic resonance, as a simple standardized, and ubiquitously applicable screening algorithm for subclinical pre-HF in rural and underresourced regions. METHODS: HERZCHECK was a cross-sectional cohort study conducted at 12 sites across rural and underresourced regions of Germany. Asymptomatic participants (40–69 years) with ≥1 cardiovascular risk factor—obesity, smoking, arterial hypertension, diabetes, hypercholesterolemia, or chronic kidney disease—were enrolled and underwent telemedically supervised contrast-free short cardiac magnetic resonance in mobile screening units. Subclinical pre-HF was diagnosed using a predefined cutoff of global longitudinal strain ≥−15%. A matched and entropy-balanced control cohort constructed from claims data was used to determine the time difference between detection of subclinical pre-HF in HERZCHECK and the first symptom-based diagnosis of HF within the standard of care. RESULTS: Between June 2021 and April 2023, 4666 participants were enrolled in the study, of which 4509 participants were included in the final analysis. The prevalence of subclinical pre-HF in the studied at-risk population was 22.7% (95% CI, 21.5%–23.9%). Global longitudinal strain-based screening identified subclinical pre-HF 6.7 years before the average onset of symptomatic HF within the standard of care (n=8420). CONCLUSIONS: Subclinical pre-HF affects approximately one-fourth of the at-risk population in rural and underresourced regions. The HERZCHECK approach identifies patients suitable for targeted preventive interventions ≈7 years earlier than the standard of care. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05122793.

Aims: Extensive research has established cardiovascular magnetic resonance (CMR) as a powerful tool for diagnosing and monitoring various cardiovascular diseases (CVDs). However, CMR has yet to reach its full potential in routine clinical care, which is mainly due to reimbursement issues. Among other factors, overcoming this gap requires adequate awareness among healthcare professionals and potential patients, the extent of which is currently unknown. Therefore, we conducted a survey to assess awareness and identify knowledge gaps regarding the clinical role and socio-economic factors associated with CMR. Methods and results: One hundred forty-four subjects not involved in direct patient care were enrolled at a German health conference and completed a 24-item survey, including procedural, clinical, and socio-economic questions about CMR. Respondents were well aware of the socio-economic impact of CVD. Common CMR indications were correctly identified by most participants, but only 22.9% knew the full spectrum. Participants underestimated the modality’s benefits, such as absence of ionizing radiation and rare allergic reactions to contrast agents (only 70.9% and 37.6% correct answers, respectively). Respondents estimated the therapeutic guidance of CMR to be high (50.7% voted impact > 50%) and the annual demand to be increasing (89.9%). Attitudes towards CMR were generally positive, with 77.1% of participants willing to travel >25 km and 60.4% willing to pay >125 Euros to have a CMR examination. Conclusion: Despite great interest in CMR, significant knowledge gaps hinder its optimal use in clinical practice. The development and implementation of awareness and education strategies are needed to realize the full clinical potential of CMR.

Background: While left-bundle-branch-block-related contraction patterns as well as echocardiography-derived strain are variably associated with the volumetric response to cardiac resynchronization therapy (CRT), the role of CMR-derived strain parameters is unexplored. Methods: A total of 50 patients receiving CRT implantation were retrospectively analyzed, all of whom had undergone CMR imaging within one year before, and echocardiography within 6 months before and 6–12 months after CRT implantation. We assessed CMR-derived morphological and functional parameters with regard to the echocardiographic response, defined as a reduction in the left ventricular end-systolic volume of ≥15%. Results: Among the standard CMR parameters, the indexed right ventricular volumes in end-diastole (RVEDVi) (74.5 ± 19.5 vs. 94.8 ± 30.2 mL/m², p = 0.006) and end-systole (RVESVi) (43.2 ± 13.3 vs. 61.6 ± 28.8 mL/m², p = 0.003), as well as the left atrial (LA) area (24.8 ± 3.5 vs. 30.4 ± 9.5 cm², p = 0.020), differed significantly between CRT responders and non-responders. In strain analysis, CRT responders showed a significantly better LA global longitudinal strain (GLS) (25.1 ± 10.4 vs. 15.3 ± 10.5, p = 0.002), LA global circumferential strain (GCS) (27.9 ± 14.7 vs. 17.1 ± 13.1%, p = 0.012), RV GLS (−25.0 ± 6.5 vs. −18.9 ± 7.6%, p = 0.004) and RV free wall strain (−31.1 ± 7.9 vs. −24.9 ± 9.5, p = 0.017). Conclusions: CMR-derived peak septal circumferential strain and RVEDVi correlated with the echocardiographic volumetric response to CRT at 6–12 months.

Background: While left-bundle-branch-block-related contraction patterns as well as echocardiography derived strain are variably associated with volumetric response to cardiac resynchronization therapy (CRT), the role of CMR-derived strain parameters is unexplored. Methods: 50 patients receiving CRT implantation were retrospectively analysed, all of which had undergone CMR imaging within one year before, and echocardiography within 6 months before and 6-12 months after CRT implantation. We assessed CMR-derived morphological and functional parameters with regard to echocardiographic response, defined as reduction of left ventricular end-systolic volume ≥15%. Results: Among standard CMR parameters, indexed right ventricular volumes in end-diastole (RVEDVi) (74.5 ±19.5 vs. 94.8 ±30.2 ml/m², P=.006) and end-systole (RVESVi) (43.2 ±13.3 vs. 61.6 ±28.8 ml/m², P=.003) as well as left atrial (LA) area (24.8 ±3.5 vs. 30.4 ±9.5 cm², P=.020) differed significantly between CRT responders and non-responders. In strain analysis, CRT responders showed significantly better LA global longitudinal strain (GLS) (25.1 ±10.4 vs. 15.3 ±10.5, P=.002), LA global circumferential strain (GCS) (27.9 ±14.7 vs. 17.1 ±13.1%, P=.012), RV GLS (-25.0 ±6.5 vs. -18.9 ±7.6%, P=.004) and RV free wall strain (-31.1 ±7.9 vs. -24.9 ±9.5, P=.017). Conclusions: CMR-derived peak septal circumferential strain and RVEDVi correlated with echocardiographic volumetric response to CRT at 6-12 months.