Journal of Cardiovascular Magnetic Resonance最新文献

Background: Concerns exist that long-term cardiac alterations occur after SARS-CoV-2 infection, particularly in patients who were hospitalized in the acute phase or who remain symptomatic. This study investigates potential long-term functional and morphological alterations after SARS-CoV-2 infection.

Methods: The authors of this study investigated patients after SARS-CoV-2 infection by using a mobile 1.5-T clinical magnetic resonance scanner for cardiac alterations. Cardiac function and dimensions were assessed using a highly efficient cardiac magnetic resonance (CMR) protocol, which included cine sequences, global longitudinal and circumferential strain assessed by fast-Strain-ENCoded imaging (fSENC), and T1 and T2 mapping. We assessed symptoms through a questionnaire. Patients were compared with a control group matched for age, gender, body mass index, and body surface area.

Results: Median follow-up time was 395 (192-408) days. The final population included 183 participants (age 48.4±14.3 years, 48.1% male). During the acute phase of SARS-CoV-2 infection, 27 patients were hospital-admitted. 42 patients reported persistent symptoms (shortness of breath, chest pain, palpitations, or leg edema), and 63 reported impaired exercise tolerance. Left ventricular functional and morphological parameters were within the normal range. T1- and T2-relaxation times were also within the normal range, indicating that the presence of myocardial edema or fibrosis were unlikely. Persistently symptomatic patients showed a slightly reduced indexed LV-SV. Functional parameters remained normal in patients who were hospitalized for SARS-CoV-2, persistently symptomatic, or with ongoing impaired exercise tolerance.

Conclusion: Irrespective of ongoing symptoms or severity of prior illness, patients who have recovered from SARS-CoV-2 infection, demonstrate normal functional and morphological cardiac parameters. Long-term cardiac changes due to SARS-CoV-2 infection appear to be rare.

Background: Although quantitative myocardial T1 and T2 mappings are clinically used to evaluate myocardial diseases, their application needs a minimum of 6 breath-holds to cover 3 short-axis slices. The purpose of this work is to simultaneously quantify multi-slice myocardial T1 and T2 across 3 short-axis slices in one breath-hold by combining simultaneous multi-slice (SMS) with Multimapping.

Methods: An SMS-Multimapping sequence with multi-band RF excitations and Cartesian FLASH readouts was developed for data acquisition. When 3 slices are simultaneously acquired, the acceleration rate is around 12-fold, causing a highly ill-conditioned reconstruction problem. To mitigate image artifacts and noise caused by the ill-conditioning, a reconstruction algorithm based on Locally Low-Rank and Sparsity (LLRS) was developed. Validation was performed in phantoms and in vivo imaging, with 20 healthy subjects and 4 patients, regarding regional mean, precision, and scan-rescan reproducibility.

Results: The phantom imaging shows that SMS-Multimapping with LLRS accurately reconstructed multi-slice T1 and T2 maps despite a 6-fold acceleration of scan time. Healthy subject imaging shows that the proposed LLRS algorithm substantially improved image quality relative to split slice-GRAPPA. Compared with MOLLI, SMS-Multimapping exhibited higher T1 mean (1118±43ms vs 1190±49ms, P<0.01), lower precision (67±17ms vs 90±17ms, P<0.01), and acceptable scan-rescan reproducibility measured by two scans 10-minute apart (bias=1.4ms for MOLLI and 9.0ms for SMS-Multimapping). Compared with bSSFP T2 mapping, SMS-Multimapping exhibited similar T2 mean (43.5±3.3ms vs 43.0±3.5ms, P=0.64), similar precision (4.9±2.1ms vs 5.1±1.0ms, P=0.93), and acceptable scan-rescan reproducibility (bias=0.13ms for bSSFP T2 mapping and 0.55ms for SMS-Multimapping). In patients, SMS-Multimapping clearly showed the abnormality in a similar fashion as the reference methods despite using only one breath-hold.

Conclusion: SMS-Multimapping with the proposed LLRS reconstruction can measure multi-slice T1 and T2 maps in one breath-hold with good accuracy, reasonable precision, and acceptable reproducibility, achieving a 6-fold reduction of scan time and an improvement of patient comfort.

Background: Cardiac bSSFP cine imaging suffers from banding and flow artifacts induced by off-resonance. The work aimed to develop a twofold phase cycling sequence with a neural network-based reconstruction (2P-SSFP+Network) for a joint suppression of banding and flow artifacts in cardiac cine imaging.

Methods: A dual-encoder neural network was trained on 1620 pairs of phase-cycled left ventricular (LV) cine images collected from 18 healthy subjects. Twenty healthy subjects and 25 patients were prospectively scanned using the proposed 2P-SSFP sequence. bSSFP cine of a single RF phase increment (1P-SSFP), bSSFP cine of a single RF phase increment with a network-based artifact reduction (1P-SSFP+Network), the averaging of the two phase-cycled images (2P-SSFP+Average), and the proposed method were mutually compared, in terms of artifact suppression performance in the LV, generalizability over altered scan parameters and scanners, suppression of large-area banding artifacts in the left atrium (LA), and accuracy of downstream segmentation tasks.

Results: In the healthy subjects, 2P-SSFP+Network showed robust suppressions of artifacts across a range of phase combinations. Compared with 1P-SSFP and 2P-SSFP+Average, 2P-SSFP+Network improved banding artifacts (3.85±0.67 and 4.50±0.45 vs 5.00±0.00, P<0.01 and P=0.02, respectively), flow artifacts (3.35±0.78 and 2.10±0.77 vs 4.90±0.20, both P<0.01), and overall image quality (3.25±0.51 and 2.30±0.60 vs 4.75±0.25, both P<0.01). 1P-SSFP+Network and 2P-SSFP+Network achieved a similar artifact suppression performance, yet the latter had fewer hallucinations (two-chamber, 4.25±0.51 vs 4.85±0.45, P=0.04; four-chamber, 3.45±1.21 vs 4.65±0.50, P=0.03; and LA, 3.35±1.00 vs 4.65±0.45, P<0.01). Furthermore, in the pulmonary veins and LA, 1P-SSFP+Network could not eliminate banding artifacts since they occupied a large area, whereas 2P-SSFP+Network reliably suppressed the artifacts. In the downstream automated myocardial segmentation task, 2P-SSFP+Network achieved more accurate segmentations than 1P-SSFP with different phase increments.

Conclusions: 2P-SSFP+Network jointly suppresses banding and flow artifacts while manifesting a good generalizability against variations of anatomy and scan parameters. It provides a feasible solution for robust suppression of the two types of artifacts in bSSFP cine imaging.

Background: Left ventricular (LV) diastolic function is a key determinant of cardiac output; impairments of diastolic function can lead to heart failure. Assessment of diastolic function is challenging due to several factors, including the load dependence of ventricular filling. We developed a method using cardiovascular magnetic resonance imaging (CMR) to model the untwisting motion of the LV as a viscoelastic damped oscillator to derive myocardial torsional modulus (µ) and frictional damping characteristics, and hypothesized that the torsional modulus would correlate with invasive measures of LV stiffness.

Methods: Twenty-two participants who underwent invasive left heart catheterization (LHC) and CMR for the evaluation of chest pain were evaluated. µ and damping constants were determined by solving a system of equations using CMR-measured LV geometrical and angular displacement data during diastole. Time constant of pressure decay τ and chamber stiffness β were measured from invasive LHC and CMR-derived volume data as comparison metrics of diastolic function.

Results: µ was correlated with chamber stiffness constant β and time constant of pressure decay τ, derived from invasive measurement (R=0.78, p<0.001, and R=0.51, p=0.014, respectively). µ was also correlated with pre-A-wave diastolic pressure (0.67, p=0.001).

Conclusions: We propose a new method to objectively evaluate diastolic relaxation properties of the LV. This method may have promise to replace invasive, catheter-based assessment of diastolic function.

Background: Cardiac symptoms due to postacute inflammatory cardiac involvement affect a broad segment of previously well people with only mild acute COVID-19 illness and without overt structural heart disease. Cardiac magnetic resonance (CMR) imaging can identify the underlying subclinical disease process, which is associated with chronic cardiac symptoms. Specific therapy directed at reducing postacute cardiac inflammatory involvement prior to development of myocardial injury and impairment is missing.

Trial design: Prospective multicentre randomised placebo-controlled study of myocardial protection therapy (combined immunosuppressive/antiremodelling) of low-dose prednisolone and losartan. Consecutive symptomatic individuals with a prior COVID-19 infection, no preexisting significant comorbidities or structural heart disease, undergo standardised assessments with questionnaires, CMR imaging and cardiopulmonary exercise testing (CPET). Eligible participants fulfilling the criteria of subclinical Post-COVID inflammatory involvement on baseline CMR examination are randomised to treatment with either verum or placebo for a total of 16 weeks (W16). Participants and investigators remain blinded to the group allocation throughout the study duration. The primary efficacy endpoint is the absolute change of left ventricular ejection fraction (LVEF) to baseline at W16, measured by CMR, between the verum treatment and placebo group by absolute difference, using unpaired t-test confirmatively at the 5% significance level. Secondary endpoints include assessment of changes of symptoms, CMR parameters, and CPET after W16, and frequency of major adverse cardiac events after 1 year. Safety data will be analysed for frequency, severity and types of adverse events (AEs) for all treatment groups. The proportion of AEs related to the contrast agent gadobutrol will also be analysed. A calculated sample size is a total of 280 participants (accounting for 8% drop-out), randomised in 1:1 fashion to 140 in the verum and 140 placebo group.

Conclusion: Myoflame-19 study will examine the efficacy of a myocardial protection therapy in symptomatic participants with post-COVID inflammatory cardiac involvement determined by CMR. The aim of the intervention is to reduce the symptoms and inflammatory myocardial injury, to improve exercise tolerance and preclude the development of cardiac impairment.

Clinical trial identifier: NCT05619653.

Background: Type 2 Diabetes (T2D) leads to cardiovascular remodeling, and heart failure has emerged as a major complication of T2D. There is a limited understanding of the impact of T2D on the right heart. This study aimed to assess subclinical right heart alterations and their contribution to aerobic exercise capacity (peak VO₂) in adults with T2D.

Methods: Single center, prospective, case-control comparison of adults with and without T2D, and no prevalent cardiac disease. Comprehensive evaluation of the left and right heart was performed using transthoracic echocardiography and stress cardiovascular magnetic resonance. Cardiopulmonary exercise testing on a bicycle ergometer with expired gas analysis was performed to determine peak VO₂. Between group comparison was adjusted for age, sex, race and body mass index using ANCOVA. Multivariable linear regression including key clinical and left heart variables, was undertaken in people with T2D to identify independent associations between measures of right ventricular (RV) structure and function with peak VO₂.

Results: 340 people with T2D (median age 64 years, 62% male, mean HbA1c 7.3%) and 66 controls (median age 58 years, 58% male, mean HbA1c 5.5%) were included. T2D participants had markedly lower peak VO₂ (adjusted mean 20.3(95% CI: 19.8-20.9) vs. 23.3(22.2-24.5) mL/kg/min, P<0.001) than controls and had smaller left ventricular (LV) volumes and LV concentric remodeling. Those with T2D had smaller RV volumes (indexed RV end-diastolic volume: 84(82-86) vs. 100(96-104) mL/m, P<0.001) with evidence of hyperdynamic RV systolic function (global longitudinal strain: 26.3(25.8-26.8) vs. 23.5(22.5-24.5) %, P<0.001) and impaired RV relaxation (longitudinal peak early diastolic strain rate: 0.77(0.74-0.80) vs. 0.92(0.85-1.00) s^-1, P<0.001). Multivariable linear regression demonstrated that RV end-diastolic volume (β=-0.342, P=0.004) and RV cardiac output (β=0.296, P=0.001), but not LV parameters, were independent determinants of peak VO₂.

Conclusions: In T2D, markers of RV remodeling are associated with aerobic exercise capacity, independent of left heart alterations.

Background: Interstitial fibrosis as quantified by cardiac magnetic resonance (CMR) has been demonstrated in arrhythmic mitral valve prolapse (AMVP), a condition with known female predominance. Prior studies of interstitial fibrosis in AMVP have only included cases with significant mitral regurgitation (MR) or mitral annular disjunction (MAD), limiting our understanding of alternative arrhythmic mechanisms in MVP. We sought to evaluate the association between interstitial fibrosis and AMVP, regardless of MAD and without severe MR, while also investigating the contribution of sex to this association.

Methods: We performed research-based contrast CMR in consecutive individuals with MVP between 2019 and 2022. Extracellular volume fraction (ECV%), a surrogate marker for interstitial fibrosis, was quantified using T₁ mapping in the basal and mid-LV slices. Replacement fibrosis was assessed using late gadolinium enhancement (LGE). AMVP was defined as MVP with frequent premature ventricular contractions and/or non-sustained/sustained ventricular tachycardia (VT) or fibrillation (VF).

Results: We identified 65 MVP cases without severe MR (46% women, 34% no/trace, 44% mild, and 21% moderate MR) and with adequate ECV% measurement. Among these, 38% were classified as AMVP, including two cases of aborted VF arrest, both in premenopausal females. Global ECV% was significantly higher in AMVP versus non-AMVP (31%[27-33] vs 27%[23-30], p=0.002). In the AMVP group, higher segmental ECV% was not limited to the inferolateral/inferior walls, typically subject to myocardial traction by the prolapsing leaflets/MAD but was more diffuse and involved atypical segments such as the anterior/anterolateral walls (p<0.05). The association between AMVP and global ECV% was driven by female sex (32%[30-34] vs 27%[25-30], p=0.002 in females; 28%[23-32] vs 26%[23-30], p=0.41 in males). ECV% remained independently associated with an increased risk of arrhythmic events, including VT/VF (p<0.01), even after adjustment for cardiovascular risk factors, MAD, and LGE (p<0.01).

Conclusion: In MVP without significant MR, interstitial fibrosis by CMR is associated with an increased risk of arrhythmic events, suggesting a primary myopathic process. The selective association between interstitial fibrosis and AMVP in females may explain why severe arrhythmic complications are more prevalent among women.

Background: Evidence to support risk stratification in Eisenmenger syndrome (ES) is still very limited. We hypothesized that biventricular longitudinal strain analysis could have potential prognostic value in ES.

Methods: We prospectively enrolled fifty-seven consecutive ES patients with post-tricuspid shunt who underwent both cardiovascular magnetic resonance (CMR) and right heart catheterization between June 2013 and March 2022. Biventricular longitudinal strains were evaluated by CMR feature-tracking analysis. The composite endpoint included all-cause mortality and re-admission for heart failure or hemoptysis. Cox regression analysis, Kaplan-Meier curves, and C-index were employed to assess the relationship between biventricular longitudinal strain and prognosis.

Results: During a median follow-up of 33 months (interquartile range: 12-50), 20 (35.1%) patients reached the composite endpoint. Patients with composite endpoints had significantly lower absolute values of left ventricular global longitudinal strain (LV GLS) and right ventricular free wall longitudinal strain (RV FWLS) than patients without composite endpoints (p < 0.05). Multivariate Cox regression analysis demonstrated that LV GLS and RV FWLS were independent predictors for composite endpoints (hazard ratio [HR]: 1.37, 95% confidence interval [CI]: 1.08-1.75, p = 0.010 and HR: 1.19, 95% CI: 1.01-1.41, p = 0.042). Kaplan-Meier analysis indicated that patients with both lower absolute values of LV GLS and RV FWLS were more likely to be at an even higher risk of composite endpoints (p < 0.001). Furthermore, the combined addition of LV GLS and RV FWLS provided incremental value for the prognostic model including clinical parameters and biventricular ejection fraction (C-index increased from 0.75 to 0.86, p = 0.004).

Conclusion: Impaired biventricular longitudinal strains improved prognostic prediction of ES patients with post-tricuspid shunt.

Background: There are few meta-analyses examining the prognostic value of right ventricular ejection fraction (RVEF) for a specific type of cardiovascular disease (CVD). The aim of this study was to compare the association of cardiac magnetic resonance (CMR)-derived RVEF with adverse outcomes for several specific types of CVD, using a robust Bayesian model-averaged meta-analysis.

Methods: Three databases were searched for CMR articles reporting hazard ratios (HRs) of RVEF restricted to a specific type of CVD. For each specific type of CVD, Bayesian model-averaged meta-analyses with and without publication bias adjustments were conducted to evaluate the strength of evidence for RVEF according to the Bayes Factor (BF).

Results: Among 108 articles (21,166 patients) analyzing 11 CVD types, pooled HR for 5% reduction in RVEF assessed by publication bias-unadjusted, Bayesian model-averaged meta-analysis offered moderate or strong evidence of an association with outcomes for all types of CVD (HR: 1.07-1.37, BF₁₀: 4.3-9.6*10⁷). In contrast, a robust Bayesian model-averaged meta-analysis, adjusted for publication bias, found moderate or strong evidence in favor of an association of RVEF with outcomes only in hypertrophic cardiomyopathy (HR: 1.19, 95% CrI: 0.98-1.42, BF₁₀: 5.0), dilated cardiomyopathy (HR: 1.16, 95% CrI: 1-1.22, BF₁₀: 23.3), pulmonary hypertension (HR: 1.05, 95% CrI: 1-1.12, BF₁₀: 3.0), and aortic stenosis (HR: 1.15, 95% CrI: 0.97-1.34, BF₁₀: 4.2). There was weak evidence for an association of RVEF with adverse outcomes in seven other CVDs.

Conclusions: In a Bayesian meta-analysis adjusted for publication bias, there was moderate or strong evidence for an association of RVEF with outcomes for only four CVDs. Additional data may strengthen evidence regarding other CVDs.

Background and purpose: Patients with coronary artery bypass grafts (CABG) face an elevated risk of major adverse cardiac events (MACE). High-dose dobutamine stress cardiovascular magnetic resonance imaging (DCMR) is a well-established technique to detect hemodynamically significant coronary artery disease (CAD). However, there is a lack of data regarding the safety of DCMR in patients with CABG. This study aims to evaluate the safety of DCMR in patients with CABG.

Methods: We retrospectively studied patients after CABG who subsequently underwent DCMR between November 2008 and July 2018. Side effects, defined as adverse events and minor symptoms, during DCMR were analyzed and compared to 200 individuals matched for age, sex and BMI without prior CABG undergoing DCMR.

Results: 336 patients (70±9 years, 85% men) were identified. Adverse events occurred in 35 CABG patients (10%) and 18 controls (9%, p=0.595). A drop of systolic blood pressure (SBP) >40mmHg (12 patients), non-sustained ventricular tachycardia (6 patients), increase in SBP >200mmHg (5 patients), monomorphic premature ventricular contractions (PVC) (2 patients), bigeminy (2 patients), left bundle-branch block (2 patients), as well as tachycardiac paroxysmal atrial fibrillation, bradycardia, supraventricular tachycardia, couplets/triplets, and sinus arrhythmia in one patient each occurred in the study group. In addition, one patient was hospitalized due to tachycardiac paroxysmal atrial fibrillation and transient ischemic attack. 29 (8.7%) examinations in the study group were aborted because of either chest pain, dyspnea, nausea, dizziness, a drop of SBP, arrhythmias, tachycardiac paroxysmal atrial fibrillation, monomorphic PVCs, or non-sustained ventricular tachycardia. The rate of aborted examination was comparable to the control group (15 (7.5%), p=0.631). Univariable logistic regression analysis revealed that female sex (OR 2.21, 95% CI 1.2 - 4.3, p=0.017) and inducible ischemia (OR 3.50, 95% CI 2.0 - 6.0, p<0.001) were associated with an increased risk of side effects during DCMR.

Conclusion: Dobutamine stress CMR did not show a relevant increase of adverse events in patients with prior CABG compared to patients without prior CABG. Female sex and dobutamine-induced myocardial ischemia are associated with side effects during DCMR.