Journal of Cardiovascular Magnetic Resonance最新文献

Purpose: To investigate image quality and agreement of derived cardiac function parameters in a novel joint image reconstruction and segmentation approach based on disentangled representation learning, enabling real-time cardiac cine imaging during free-breathing.

Methods: A multi-tasking neural network architecture, incorporating disentangled representation learning, was trained using simulated examinations based on data from a public repository along with MR scans specifically acquired for model development. An exploratory feasibility study evaluated the method on undersampled real-time acquisitions using an in-house developed spiral bSSFP pulse sequence in eight healthy participants and five patients with intermittent atrial fibrillation. Images and predicted LV segmentations were compared to the reference standard of ECG-gated segmented Cartesian cine with repeated breath-holds and corresponding manual segmentation.

Results: On a 5-point Likert scale, image quality of the real-time breath-hold approach and Cartesian cine was comparable in healthy participants (RT-BH: 1.99 ±.98, Cartesian: 1.94 ±.86, p=.052), but slightly inferior in free-breathing (RT-FB: 2.40 ±.98, p<.001). In patients with arrhythmia, both real-time approaches demonstrated favourable image quality (RT-BH: 2.10 ± 1.28, p<.001, RT-FB: 2.40 ± 1.13, p<.01, Cartesian: 2.68 ± 1.13). Intra-observer reliability was good (ICC=.77,95%-confidence interval [.75,.79], p<.001). In functional analysis, a positive bias was observed for ejection fractions derived from the proposed model compared to the clinical reference standard (RT-BH mean: 58.5 ± 5.6%, bias: +3.47%, 95%-confidence interval [-.86, 7.79%], RT-FB mean: 57.9 ± 10.6%, bias: +1.45%, [-3.02, 5.91%], Cartesian mean: 54.9 ± 6.7%).

Conclusion: The introduced real-time MR imaging technique enables high-quality cardiac cine data acquisitions in 1-2minutes, eliminating the need for ECG gating and breath-holds. This approach offers a promising alternative to the current clinical practice of segmented acquisition, with shorter scan times, improved patient comfort, and increased robustness to arrhythmia and patient non-compliance.

Background: This study aims to identify optimal acceleration factors (AFs) for compressed sensing (CS) technology to enhance its clinical application for suspected coronary artery disease (CAD) in whole-heart non-contrast coronary magnetic resonance angiography (CMRA).

Methods: Two hundred and seventeen individuals with suspected CAD underwent whole-heart non-contrast CMRA on a 1.5-T CMR scanner with CS AFs of 2, 4, and 6 (CS2, CS4, and CS6). Two radiologists independently and blindly scored the image quality. The overall image scores, coronary artery segment scores, signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and scan times were compared. The scores for left anterior descending artery (LAD), left circumflex branch (LCX), and right coronary artery (RCA) were assessed. Of the 217 patients, 37 (17.1%) underwent X-ray coronary angiography (CAG). The images from CS2, CS4, and CS6 were evaluated by two radiologists blinded to CAG results to identify significant luminal narrowing. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated.

Results: The CS2 group exhibited higher overall scores, coronary artery segment scores, SNR, and CNR, but longer scan times compared to the CS4 and CS6 groups (Overall Score: 24.50 vs 22.00 vs 21.00, p<0.001; SNR: 127.23 vs 112.14 vs 99.45, p<0.001; CNRcor-fat: 118.33 vs 101.25 vs 84.17, p<0.001; CNRcor-myo: 69.67 vs 62.83 vs 53.50, p<0.001; Scan Time: 884.2±308.2s vs 472.8±163.0s vs 330.7±145.9s, p<0.001). Proximal and middle segments received higher scores compared to their corresponding distal segments, and the RCA exhibited higher image quality than LAD and LCX in all groups (p<0.05). In the subgroup analysis, 19 (51.3%) were diagnosed with CAD by CAG. The sensitivity, specificity, PPV, NPV, and accuracy were as follows: CS2 (94.7%, 88.9%, 90.0%, 94.1%, and 91.9%), CS4 (89.5%, 94.4%, 94.4%, 89.5%, and 91.9%), and CS6 (89.5%, 66.7%, 73.9%, 85.7%, and 78.4%), respectively, in patient-based analysis.

Conclusion: Image quality showed a decreasing trend with increasing CS AFs, while scan time decreased in non-contrast CMRA. A scanning protocol using CS4 provided high-quality images with relatively short scan times and showed potential for detecting significant coronary stenosis, making it an optimal protocol for coronary magnetic resonance imaging.

Background: Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) shows promise for quantifying mitral regurgitation (MR) by allowing for direct regurgitant volume (RVol) measurement using a plane precisely placed at the MR jet. However, the ideal location of a measurement plane remains unclear. This study aims to systematically examine how varying measurement locations affect RVol quantification and determine the optimal location using the momentum conservation principle of a free jet.

Methods: Patients diagnosed with MR by transthoracic echocardiography (TTE) and scheduled for CMR were prospectively recruited. Regurgitant jet flow volume (RVol_jet) and regurgitant jet flow momentum (RMom_jet) were quantified using 4D flow CMR at 7 locations along the jet axis, x. The reference plane (mid-plane, x=0mm) was positioned at the peak velocity of the jet at each cardiac phase, and 3 additional planes were positioned on either side of the jet, each 2.5mm apart. RVol_jet was compared to RVol_TTE, measured by the proximal isovelocity surface area method and RVol_indirect, measured by subtracting aortic forward flow volume from the left ventricle stroke volume derived from 2D phase-contrast at the aortic valve and a stack of short-axis cine CMR techniques.

Results: RVol_jet and RMom_jet were quantified in 45 patients (age 63±13, male 26). In patients with RVol_jet at x=0mm ≥ 10ml (n=25), RVol_jet consistently increased as the plane moved downstream. RVol_jet measured furthest upstream (x=-7.5mm) was significantly lower (39±11%, p<0.001) and RVol_jet measured furthest downstream (x=7.5mm) was significantly higher (16±19%, p<0.001) than RVol_jet at x=0mm. RMom_jet similarly increased from x=-7.5 to 0mm (57±12%, p<0.001) but stabilized from x=0 to 7.5mm (-2±17%). From x=-7.5 to 7.5mm, RVol_jet was in consistent moderate agreement with RVol_indirect (n=41, bias=-2±24 to 8±32ml, ICC=0.55 to 0.63, p<0.001).

Conclusion: The location of a measurement plane significantly influences RVol quantification using the direct 4D flow CMR approach. Based on the converging profile of RMom_jet, we propose the peak velocity of the jet as the optimal position.

Background and aims: Heart failure (HF) is an imminent global health problem. Yet established screening algorithms for asymptomatic pre-HF, allowing for early and effective preventive interventions, are largely lacking. The HERZCHECK trial, conducted in structurally underserved rural regions of North-Eastern Germany, aims to close this gap by evaluating the feasibility, diagnostic efficacy, and cost-effectiveness of a fully mobile, telemedically-supervised screening approach, combining cardiac magnetic resonance imaging (CMR) and laboratory testing as central elements.

Study design and methodology: The HERZCHECK trial is a prospective, randomized controlled trial employing a PROBE (prospective randomized open, blinded endpoint) design. The study targets asymptomatic adults aged 40-69 years without a history of HF, but with at least one of the following cardiovascular risk factors: hypertension, hypercholesterolemia, obesity, smoking/tobacco consumption, chronic diabetes mellitus, or chronic kidney disease. Participants undergo a comprehensive screening examination including a questionnaire-based medical history, laboratory testing, and CMR at baseline. Based on CMR-derived global longitudinal strain (GLS), participants are classified as stratum A (GLS < -15%), B (GLS ≥ -15% to < -11%), or C (GLS ≥ -11%), with strata B and C being defined as asymptomatic pre-HF. 10% of participants in stratum A and all of stratum B and C are subsequently randomized into two groups, receiving either conventional or innovative medical reports, the latter including information on GLS, guideline-based recommendations, and access to a life-style intervention app for cardiovascular prevention. Additionally, treating physicians of participants in the innovative group are granted access to an expert center for telemedical enquires. Follow-up assessments are performed over 12 months to evaluate changes in GLS, as well as adverse cardiac events and quality of life.

Conclusion: HERZCHECK aims to provide a blueprint for a comprehensive, contemporary screening approach tailored to the needs of the targeted structurally underserved population. By implementing this approach in a representative at-risk cohort, HERZCHECK will provide important new information about (a) the prevalence of asymptomatic pre-HF in at-risk patients and (b) the feasibility, added diagnostic value and health economic aspects of CMR exams as part of future screening mechanisms for HF in clinical routine care. (NCT05122793).

Background: Patients after kidney transplantation (KTx) in childhood show a high prevalence of cardiac complications, but the underlying mechanism is still poorly understood. In adults, myocardial fibrosis detected in cardiac magnetic resonance (CMR) imaging is already an established risk factor. Data for children after KTx are not available. This study aimed to explore cardiac function and structure with focus on myocardial fibrosis and associated risk factors in KTx recipients.

Methods: 46 KTx recipients (mean age 16.0 ± 3.5 years) and 46 age- and sex-matched healthy controls were examined with non-contrast CMR imaging. Native T1 time (nT1), a marker for myocardial fibrosis, was measured at the interventricular septum. Other parameters comprised left ventricular mass index (LVMI), ejection fraction (LVEF), and global longitudinal strain (GLS). Multivariable linear regression analyses were used to explore associations with nT1.

Results: Mean nT1 was significantly higher in KTx recipients than in controls (1198.1±48.8ms vs. 1154.4±23.4ms, p<0.0001). Twenty-one (46%) had a nT1 above above the upper limit of the normal range (mean + 2SD of controls). KTx recipients showed higher LVMI z-scores (0.1±1.1 vs. -0.3±0.7, p=0.026), higher LVEF (67.3±3.8% vs. 65.3±3.6%, p=0.012), and lower GLS (-19.0±2.1% vs. -20.3±2.7%, p=0.010). Higher systolic blood pressure (SBP; ß=1.284, p=0.001), LVMI (ß=1.542, p<0.001), and LVEF (ß=3.535, p=0.026) were associated with longer nT1 only in KTx recipients, but not in controls. Only two KTx recipients exhibited left ventricular hypertrophy, however, a total of 18 displayed elevated nT1 with LVMI z-score within the normal range.

Conclusion: Our data suggest the presence of cardiac remodeling with myocardial fibrosis in a significant proportion of young KTx recipients. Non-contrast CMR imaging has the potential to visualize early structural cardiac changes and could become an important diagnostic adjunct in the follow-up of KTx recipients. Longitudinal studies are needed to further evaluate the importance of nT1 in early identification of those at high risk for sudden cardiac death allowing to integrate preventive strategies.

Background: Mitral annular disjunction (MAD) is a controversial entity. Recently, a distinction between pseudo-MAD, present in systole and secondary to juxtaposition of the billowing posterior leaflet on the left atrial wall, and true-MAD, where the insertion of the posterior leaflet is displaced on the atrial wall both in diastole or in systole, has been proposed. We investigated the prevalence of pseudo-MAD and true-MAD.

Methods: This was a retrospective study, including consecutive patients referred to cardiovascular magnetic resonance (CMR). MAD was defined as a ≥1 mm displacement between the left atrial wall-mitral valve leaflet junction hinge and the top of the left ventricular wall, measured from cine-CMR images in the three long-axis views. Pseudo-MAD and true-MAD were defined as the presence of MAD only in systole or both in systole and diastole, respectively.

Results: Two hundred and ninety patients (59 [47-71] years; 181/290 men, 62%) were included. Mitral valve prolapse (MVP) and MAD were found in 24/290 (8%) and 145/290 (50%) patients, of which 100/290 (35%) with true-MAD and 45/290 (16%) with pseudo-MAD. In all measurements, systolic MAD extent (2.3 [1.7-3.0] mm) resulted equal to or greater than diastolic MAD extent (2.0 [1.5-2.9] mm). The most frequent MAD location was the inferior wall (117/290, 40%) and the inferolateral wall was the rarest (50/290, 17%). In patients with MVP, the prevalence of MAD was higher (21/24, 88%), mainly driven by a higher prevalence of pseudo-MAD, as the prevalence of true-MAD did not vary significantly in patients with vs without MVP (p = 0.22), except for the inferolateral wall (9/24, 38% vs 20/266, 8%; p < 0.001). The extent of pseudo-MAD was greater in patients with MVP (4.0 [3.0-5.6] mm) than in those without MVP (2.0 [1.5-3.0]; p < 0.001), whereas the extent of true-MAD did not differ significantly (2.5 [2.0-3.2] mm and 1.9 [1.5-2.9] mm; p = 0.06). At the inferolateral wall, the prevalence of pseudo-MAD was 7/24, 29% vs 14/266, 5% (p < 0.001) in patients with vs without MVP.

Conclusion: True-MAD was a common imaging finding in patients undergoing CMR, irrespective of MVP. Patients with MVP showed higher prevalence and extent of pseudo-MAD in all locations and true-MAD in the inferolateral wall.

With a prevalence of 2-3% in the general population, mitral valve prolapse (MVP) is the most common valvular heart disease. The clinical course is benign in the majority of patients, although severe mitral regurgitation, heart failure, and sudden cardiac death affect a non-negligible subset of patients. Imaging of MVP was confined to echocardiography until a few years ago when it became apparent that cardiovascular magnetic resonance (CMR) could offer comparative advantages for detecting and quantifying mitral valve abnormalities alongside tissue myocardial characterization. The present review highlights the growing body of evidence supporting the role of CMR in patients with MVP. Based on the recent literature, CMR appears not as a simple alternative to echocardiography in patients with poor acoustic windows, but as a complementary imaging modality instrumental for better quantifying mitral valve abnormalities, mitral regurgitation severity, ventricular remodeling, and myocardial tissue changes. In this respect, pivotal CMR studies highlight that mitral annular disjunction and myocardial fibrosis by late gadolinium enhancement are associated with a heightened risk of life-threatening ventricular arrhythmias (arrhythmic MVP). We also delineate how these and other markers (e.g., the severity of mitral regurgitation) could enable a personalized risk assessment in patients with MVP and implement clinical decision-making. Here, we provide a comprehensive review of the current literature, with an emphasis on the arrhythmic MVP phenotype. The review also provides some practical suggestions on how to carry out a dedicated CMR protocol in MVP and composes a thorough report to inform clinicians on key aspects of this valvular heart disease.

Background: Multiparametric cardiovascular magnetic resonance (CMR) has an emerging role in non-invasive surveillance of pediatric heart transplant recipients (PHTR). Higher myocardial T2, higher extracellular volume fraction (ECV), and late gadolinium enhancement (LGE) have been associated with adverse clinical outcomes in adult heart transplant recipients. The purpose of this study was to investigate the prognostic value of CMR-derived T1 and T2 mapping, ECV, and LGE for clinical outcomes in PHTR.

Methods: We performed a single-center, retrospective chart review of consecutive, gadolinium-enhanced CMR studies in PHTR over a 7.5-year period, excluding follow-up studies. Standard CMR ventricular volume and function analysis, T1 mapping with ECV, T2 mapping, and LGE assessment were performed. The composite outcome included cardiac death, non-cardiac death, re-transplantation, and cardiac hospitalization.

Results: Among 113 PHTR, mean age was 13.0 ± 5.1 years, with 6.0 ± 4.0 years since transplant. The indication for CMR was surveillance in 79%. Mean native T1 was 1050 ± 48 ms, T2 49.2 ± 3.9 ms, and ECV 29.7 ± 4.5%. Left ventricular LGE was present in 37% (42/113) and right ventricular LGE in 3.5% (4/113). The mean follow-up time was 2.3 years and median was 1.4 years. Cardiac death occurred in 2% (2/113), re-transplantation in 4% (4/113), and cardiac hospitalization in 22% (25/113). Non-cardiac death did not occur. Using Kaplan-Meier analysis, high T1 (≥1061 ms), T2 (≥50.0 ms), and ECV (≥31.4%) were each associated with decreased freedom from the composite outcome in follow-up. In univariable Cox regression analyses, high T1 was associated with increased risk of the composite outcome (hazard ratios [HR] 4.0, 95% confidence interval [CI] 1.7-9.2, p = 0.001), as were high T2 (HR 2.8, 95% CI 1.1-7.1, p = 0.026), and high ECV (HR 3.5, 95% CI 1.5-8.1, p = 0.004).

Conclusion: T1 and T2 mapping are associated with early differences in adverse cardiac events in PHTR. These data suggest a role for a multicenter study with a longer follow-up duration.

Background: Recent evidence underscores the importance of cardiovascular magnetic resonance (CMR) in light chain amyloidosis (AL amyloidosis). We aimed to comprehensively assess the prognostic significance of CMR parametric mapping in AL amyloidosis.

Methods: This prospective study consecutively included AL amyloidosis patients who underwent CMR imaging before therapy. The statistical analyses included T2, extracellular volume, and native T1 as variates under investigation, adjusted for well-established prognostic markers. The outcome was death from any cause.

Results: In total, 195 patients (age, 57.2 ± 9.1 years; male/female, 123/72) were recruited. At the median follow-up time (19 months), the survival probability was approximately 67.2% (131/195). T >44 ms, extracellular volume fraction (ECV) >47%, and native T1 >1468 ms were significantly prognostic (all, P < 0.05) but non-significant after adjustment for N-terminal pro-B-type natriuretic peptide (all, P > 0.05) in AL amyloidosis. T2 >44 ms was independently prognostic after correcting for left ventricle (LV) late gadolinium enhancement, LV ejection fraction, LV longitudinal strain, and therapeutic response (all, P < 0.05). In patients achieving deep hematologic response, T2 >44 ms (hazard ratios [HR] 6.611, 95% confidence interval [CI] 1.723-25.361, P = 0.006) was significantly prognostic for mortality after adjustment for cardiac response. Accordingly, T2 >44 ms was significantly associated with mortality (HR 5.734, 95% CI 1.189-27.656, P = 0.030) and remained independently prognostic after correcting for LV late gadolinium enhancement and LV longitudinal strain (both, P < 0.05) in patients who achieved both deep hematologic response and cardiac response.

Conclusion: This study highlights that T2 is a valuable independent predictor of mortality in an AL amyloidosis population, additive to common CMR risk factors. Moreover, myocardial edema assessment identified patients in need of adjunctive therapies, which is of particular prognostic significance in patients with deep therapeutic response.

Background: Cardiac involvement in light chain amyloidosis (AL) is the main determinant of prognosis. Amyloid can be deposited in the extracellular space and cause an increase in extracellular volume fraction (ECV). At the same time, amyloid can also be deposited in the wall of small vessels and cause microvascular dysfunction. This study sought to investigate the extent of microvascular dysfunction and its incremental prognostic value in cardiac light-chain amyloidosis (AL-CA) by quantitative stress perfusion.

Methods: A total of 126 AL amyloidosis patients (61.13 ± 8.46 years, 81 male) confirmed by pathology were prospectively recruited. All subjects underwent cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE), T1 mapping, and stress perfusion on a 3T scanner. ECV and myocardial perfusion reserve (MPR) were measured semi-automatically using a dedicated CMR software. Clinical, laboratory, and CMR parameters were analyzed for their prognostic value in the assessment of AL-CA patients. Mortality-associated markers were analyzed by univariate and multivariable Cox regression.

Results: The median follow-up time was 37 (33.6-40.4) months, and 62 patients died. The ECV of survivors was significantly reduced, but the stress myocardial blood flow and MPR were higher (P < 0.001). The MPR of the transmural LGE group was significantly lower than that of the no LGE and subendocardial LGE groups (P < 0.001). In multivariable analysis, ECV, MPR, and LGE were independently predictive. MPR of >1.5 and ECV of ≤53.6% were associated with improved overall survival, both of which provided predictive incremental value in patients with advanced disease. With equal Mayo staging and degree of ECV, MPR improves assessment of patient survival.

Conclusion: ECV and MPR showed additive incremental values and further discriminated prognosis of patients in advanced stages. CMR phenotypes with higher ECV and lower MPR had a worse prognosis.