A case series of double-chambered left ventricle detected by cardiovascular magnetic resonance.

Background: Double-chambered left ventricle (DCLV) is a rare congenital condition, and few case reports are mentioned in literature. Entity, clinical course, and prognosis remain unclear. Cardiovascular magnetic resonance (CMR) is often used for characterization of various congenital heart diseases and can be particularly useful for imaging rare phenomena. Case summary: Three cases of DCLV were detected by CMR within 2 years in our CMR centre with and without associated congenital heart disease or hypertrabecularization. The patients did not suffer from cardiac symptoms despite the presence of premature ventricular complexes in one patient. Diagnosis of DCLV was made based on a first CMR study that was performed in adulthood, although some anatomical suspicion was already raised by previous echocardiography. Discussion: Double-chambered left ventricle, synonymous with the terminus 'cor triventriculare sinistrum', has been previously perceived as a rare phenomenon compared with double-chambered right ventricle. It has to be distinguished from ventricular aneurysm or cardiac diverticulum and is characterized by an additional contractile septum with normal wall structure that divides the LV cavum into two (rather) same-sized chambers. The prognosis seems to be benign, since there is no restriction in functionality and no increased thrombogenicity until adulthood. Consequently, there is (presumably) no need for a tailored therapy-at least in the cases present here. Accordingly, we recommend follow-up CMR examinations for progress monitoring and recognize CMR's significant role for diagnosis and follow-up of cardiac abnormalities in orphan diseases. Due to its broader availability, we expect further cases of DLVC in the future.

Therapeutic value of tafamidis in patients with wild-type transthyretin amyloidosis (ATTRwt) with cardiomyopathy based on cardiovascular magnetic resonance (CMR) imaging.

OBJECTIVES: The purpose of this study was to carefully analyse the therapeutic benefit of tafamidis in patients with wild-type transthyretin amyloidosis (ATTRwt) and cardiomyopathy (ATTRwt-CM) after one year of therapy based on serial multi-parametric cardiovascular magnetic resonance (CMR) imaging. BACKGROUND: Non-sponsored data based on multi-parametric CMR regarding the effect of tafamidis on the cardiac phenotype of patients with ATTRwt-CM are not available so far. METHODS: The present study comprised N = 40 patients with ATTRwt-CM who underwent two serial multi-parametric CMR studies within a follow-up period of 12 ± 3 months. Baseline (BL) clinical parameters, serum biomarkers and CMR findings were compared to follow-up (FU) values in patients treated "with" tafamidis 61 mg daily (n = 20, group A) and those "without" tafamidis therapy (n = 20, group B). CMR studies were performed on a 1.5-T system and comprised cine-imaging, pre- and post-contrast T1-mapping and additional calculation of extracellular volume fraction (ECV) values. RESULTS: While left ventricular ejection fraction (LV-EF), left ventricular mass index (LVMi), left ventricular wall thickness (LVWT), native T1- and ECV values remained unchanged in the tafamidis group A, a slight reduction in LV-EF (p = 0.003) as well as a subtle increase in LVMi (p = 0.034), in LVWT (p = 0.001), in native T1- (p = 0.038) and ECV-values (p = 0.017) were observed in the untreated group B. Serum NT-proBNP levels showed an overall increase in both groups, however, with the untreated group B showing a relatively higher increase compared to the treated group A. Assessment of NYHA class did not result in significant intra-group differences when BL were compared with FU, but a trend to improvement in the treated group A compared to a worsening trend in the untreated group B (∆p = 0.005). CONCLUSION: As expected, tafamidis does not improve cardiac phenotype in patients with ATTRwt-CM after one year of therapy. However, tafamidis seems to slow down cardiac disease progression in patients with ATTRwt-CM compared to those without tafamidis therapy based on multi-parametric CMR data already after one year of therapy.

A compartment-based myocardial density approach helps to solve the native T1 vs. ECV paradox in cardiac amyloidosis.

Cardiovascular magnetic resonance (CMR) plays an important clinical role for diagnosis and therapy monitoring of cardiac amyloidosis (CA). Previous data suggested a lower native T1 value in spite of a higher LV mass and higher extracellular volume fraction (ECV) value in wild-type transthyretin amyloidosis (ATTRwt) compared to light-chain amyloidosis (AL)-resulting in the still unsolved "native T1 vs. ECV paradox" in CA. The purpose of this study was to address this paradox. The present study comprised N = 90 patients with ATTRwt and N = 30 patients with AL who underwent multi-parametric CMR studies prior to any specific treatment. The CMR protocol comprised cine- and late-gadolinium-enhancement (LGE)-imaging as well as T2-mapping and pre-/post-contrast T1-mapping allowing to measure myocardial ECV. Left ventricular ejection fraction (LV-EF), left ventricular mass index (LVMi) and left ventricular wall thickness (LVWT) were significantly higher in ATTRwt in comparison to AL. Indexed ECV (ECVi) was also higher in ATTRwt (p = 0.041 for global and p = 0.001 for basal septal). In contrast, native T1- [1094 ms (1069-1127 ms) in ATTRwt vs. 1,122 ms (1076-1160 ms) in AL group, p = 0.040] and T2-values [57 ms (55-60 ms) vs. 60 ms (57-64 ms); p = 0.001] were higher in AL. Considering particularities in myocardial density, "total extracellular mass" (TECM) was substantially higher in ATTRwt whereas "total intracellular mass" (TICM) was rather similar between ATTRwt and AL. Consequently, the "ratio TICM/TECM" was lower in ATTRwt compared to AL (0.58 vs. 0.83; p = 0.007). Our data confirm the presence of a "native T1 vs. ECV paradox" with lower native T1 values in spite of higher myocardial mass and ECV in ATTRwt compared to AL. Importantly, this observation can be explained by particularities regarding myocardial density that result in a lower TICM/TECM "ratio" in case of ATTRwt compared to AL-since native T1 is determined by this ratio.

Serial Cardiovascular Magnetic Resonance Studies Prior to and After mRNA-Based COVID-19 Booster Vaccination to Assess Booster-Associated Cardiac Effects.

Background: mRNA-based COVID-19 vaccination is associated with rare but sometimes serious cases of acute peri-/myocarditis. It is still not well known whether a 3rd booster-vaccination is also associated with functional and/or structural changes regarding cardiac status. The aim of this study was to assess the possible occurrence of peri-/myocarditis in healthy volunteers and to analyze subclinical changes in functional and/or structural cardiac parameters following a mRNA-based booster-vaccination. Methods and Results: Healthy volunteers aged 18-50 years (n = 41; m = 23, f = 18) were enrolled for a CMR-based serial screening before and after 3rd booster-vaccination at a single center in Germany. Each study visit comprised a multi-parametric CMR scan, blood analyses with cardiac markers, markers of inflammation and SARS-CoV-2-IgG antibody titers, resting ECGs and a questionnaire regarding clinical symptoms. CMR examinations were performed before (median 3 days) and after (median 6 days) 3rd booster-vaccination. There was no significant change in cardiac parameters, CRP or D-dimer after vaccination, but a significant rise in the SARS-CoV-2-IgG titer (p < 0.001), with a significantly higher increase in females compared to males (p = 0.044). No changes regarding CMR parameters including global native T1- and T2-mapping values of the myocardium were observed. A single case of a vaccination-associated mild pericardial inflammation was detected by T2-weighted CMR images. Conclusion: There were no functional or structural changes in the myocardium after booster-vaccination in our cohort of 41 healthy subjects. However, subclinical pericarditis was observed in one case and could only be depicted by multiparametric CMR.

Hybrid CMR- and FDG-PET-Imaging Gives New Insights Into the Relationship of Myocardial Metabolic Activity and Fibrosis in Patients With Becker Muscular Dystrophy.

BACKGROUND: Cardiac involvement in patients with Becker muscular dystrophy (BMD) is an important predictor of mortality. The cardiac phenotype of BMD patients is characterized by slowly progressive myocardial fibrosis that starts in the left ventricular (LV) free wall segments and extends into the septal wall during the disease course. PURPOSE: Since the reason for this characteristic cardiac phenotype is unknown and comprehensive approaches using e.g. hybrid imaging combining cardiovascular magnetic resonance (CMR) with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) are limited, the present study addressed this issue by a comprehensive non-invasive imaging approach. METHODS: Hybrid CMR- and FDG-PET-imaging was performed in N = 14 patients with BMD on a whole-body Biograph mMR system (Siemens, Erlangen, Germany). The CMR protocol comprised cine- and late-gadolinium-enhancement (LGE)-imaging. Metabolism was assessed with FDG-PET after oral glucose loading to effect myocardial carbohydrate uptake. PET was acquired for 65 min starting with tracer injection. Uptake values from 60 to 65 min p.i. were divided by the area under the blood activity curve and reported as percentages relative to the segment with maximal myocardial FDG uptake. RESULTS: A characteristic pattern of LGE in the LV lateral wall was observed in 13/14 patients whereas an additional septal LGE pattern was documented in 6/14 patients only. There was one patient without any LGE. Segmental FDG uptake was 88 ± 6% in the LV lateral wall vs. 77 ± 10% in the septal wall (p < 0.001). There was an inverse relationship between segmental FDG activity compared to segmental LGE extent (r = -0.33, p = 0.089). There were N = 6 LGE-positive patients with a segmental difference in FDG uptake of >15% in the LV lateral wall compared to the septal wall = ΔFDG-high group (lateral FDG = 91±3% vs. septal FDG = 69±8%; p < 0.001) while the remaining N = 7 LGE-positive patients showed a segmental difference in FDG uptake of ≤ 15% = ΔFDG-low group (lateral FDG = 85±7% vs. septal FDG = 83 ± 5%; p = 0.37). Patients in the ΔFDG-high group showed only a minor difference in the LGE extent between the LV lateral wall vs. septal wall (p = 0.09) whereas large differences were observed in the ΔFDG-low group (p < 0.004). CONCLUSIONS: Segmental FDG uptake-reflecting myocardial metabolic activity-is higher in the LV free wall of BMD patients-possibly due to a higher segmental work load. However, segmental metabolic activity seems to be dependent on and limited by the respective segmental extent of myocardial fibrosis as depicted by LGE-imaging.