Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in polymyalgia rheumatica: an observational study.

OBJECTIVES: Polymyalgia rheumatica (PMR) is an inflammatory disease with a diagnosis that is sometimes difficult to establish. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) might be helpful. We analysed the usefulness of 18F-FDG PET/CT for the diagnosis of PMR. METHODS: This was an observational retrospective study of individuals with PMR who underwent 18F-FDG PET/CT and a control group. We assessed clinical and 18F-FDG PET/CT characteristics. Sixteen sites were studied. The number of sites with significant FDG uptake, the mean maximum standardised uptake value (SUVmax) and the highest SUVmax value were assessed for each patient. RESULTS: Data for 123 patients with PMR (37 with corticosteroids [CSTs] use) were analysed; 85 had new-onset PMR. As compared with the 75 controls, patients with new-onset PMR had higher mean ± SD number of sites with significant FDG uptake (11.3 ± 3.3 vs. 0.9 ± 1.1, p<0.001) and higher SUVmax scores (p<0.001). A cut-off of 5 hypermetabolic sites provided sensitivity of 96.5% and specificity 100%. For the total SUVmax score, a cut-off of 3 had the best sensitivity (92.6%) and specificity (86.1%). As compared with PMR patients using CSTs, those who were CST-naive had significantly higher CRP level (p<0.001), number of sites with significant FDG uptake (p<0.001) and SUVmax scores (p<0.01). In contrast, large-vessel vasculitis was more frequent in patients receiving CSTs than CST-naive patients (27% vs. 8%, p<0.01). CONCLUSIONS: The number of hypermetabolic sites or SUVmax quantification might be useful for PMR diagnosis, and CSTs might affect the results of 18F-FDG PET/CT.

FDG atrial uptake is associated with an increased prevalence of stroke in patients with atrial fibrillation.

PURPOSE: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with an increased risk of stroke. Indeed, silent AF is frequently identified in unexplained ischemic stroke. 18F-FDG-PET/CT is a powerful tool for assessing myocardial metabolic shift and inflammation, both potentially at stake in AF. This case-control study investigated whether AF could promote FDG uptake in atria after physiological myocardial glucose uptake suppression, and the potential relationship between FDG atrial uptake and prevalence of stroke. METHODS: We retrospectively enrolled 128 patients (64 consecutive patients with AF and 64 without AF as the control group, matched for age and sex) who underwent 18F-FDG-PET/CT after a high-fat low-carbohydrate diet. We analyzed visual and quantitative FDG uptake parameters of the right and left atria (RA/LA) and the right and left appendages (RAA/LAA), and selected clinical features including history of stroke. RESULTS: Diffuse right atrial uptake was present in a third of patients with AF and only two patients in the control group. FDG uptake intensity of both atria was significantly associated with the underlying heart rhythm. The occurrence of stroke was strongly associated with detectable atrial uptake in multivariate analysis, with an odds ratio superior to that of other known risk factors. CONCLUSIONS: This study shows a significant correlation between FDG atrial uptake and AF. While inconsistent, this pattern seems to be associated with an increased prevalence of cardioembolic stroke.

Cardiac denervation evidenced by MIBG occurs earlier than amyloid deposits detection by diphosphonate scintigraphy in TTR mutation carriers.

PURPOSE: Cardiac involvement in familial transthyretin (TTR) amyloidosis is of major prognostic value, and the development of early-diagnostic tools that could trigger the use of new disease-modifying treatments is crucial. The aim of our study was to compare the respective contributions of 99mTc-diphosphonate scintigraphy (DPD, detecting amyloid deposits) and 123I-MIBG (MIBG, assessing cardiac sympathetic denervation) in patients with genetically proven TTR mutation referred for the assessment of cardiac involvement. METHODS: We prospectively studied 75 consecutive patients (classified as symptomatic or asymptomatic carriers), using clinical evaluation, biomarkers (troponin and BNP), echocardiography, and nuclear imaging. Patients were classified as having normal heart-to-mediastinum (HMR) MIBG uptake ratio 4 h after injection (defined by HM4 ≥ 1.85) or abnormal HM4 < 1.85, and positive DPD uptake (grade ≥ 1 of Perugini classification) or negative DPD uptake. RESULTS: Among 75 patients, 49 (65%) presented with scintigraphic sympathetic cardiac denervation and 29 (39%) with myocardial diphosphonate uptake. When MIBG was normal, DPD was negative except for two patients. Age was an independent predictor of abnormal scintigraphic result of both MIBG and DPD (HR 1.08 and 1.15 respectively), whereas echocardiographic-derived indicators of increased left ventricular filling pressure (E/e' ratio) was an independent predictor of abnormal MIBG (HR 1.33) and global longitudinal strain of positive DPD (HR 1.45). In asymptomatic patients (n = 31), MIBG was abnormal in 48% (n = 15) among whom 50% had a normal DPD; all those with a normal MIBG (n = 16) had a normal DPD. CONCLUSIONS: In TTR mutation carriers, cardiac sympathetic denervation evidenced by decreased MIBG uptake is detected earlier than amyloid burden evidenced by DPD. These results raise the possibility of a diagnostic role for MIBG scintigraphy at an early stage of cardiac involvement in TTR-mutated carriers, in addition to its well-established prognostic value.

Two-dimensional XD-GRASP provides better image quality than conventional 2D cardiac cine MRI for patients who cannot suspend respiration.

OBJECTIVES: Residual respiratory motion degrades image quality in conventional cardiac cine MRI (CCMRI). We evaluated whether a free-breathing (FB) radial imaging CCMRI sequence with compressed sensing reconstruction [extradimensional (e.g. cardiac and respiratory phases) golden-angle radial sparse parallel, or XD-GRASP] could provide better image quality than a conventional Cartesian breath-held (BH) sequence in an unselected population of patients undergoing clinical CCMRI. MATERIALS AND METHODS: One hundred one patients who underwent BH and FB imaging in a midventricular short-axis plane at a matching location were included. Visual and quantitative image analysis was performed by two blinded experienced readers, using a five-point qualitative scale to score overall image quality and visual signal-to-noise ratio (SNR) grade, with measures of noise and sharpness. End-diastolic and end-systolic left ventricular areas were also measured and compared for both BH and FB images. RESULTS: Image quality was generally better with the BH cines (overall quality grade for BH vs FB images 4 vs 2.9, p < 0.001; noise 0.06 vs 0.08 p < 0.001; SNR grade 4.1 vs 3, p < 0.001), except for sharpness (p = 0.48). There were no significant differences between BH and FB images regarding end-diastolic or end-systolic areas (p = 0.35 and p = 0.12). Eighteen of the 101 patients had poor BH image quality (grade 1 or 2). In this subgroup, the quality of the FB images was better (p = 0.0032), as was the SNR grade (p = 0.003), but there were no significant differences regarding noise and sharpness (p = 0.45 and p = 0.47). CONCLUSION: Although FB XD-GRASP CCMRI was visually inferior to conventional BH CCMRI in general, it provided improved image quality in the subgroup of patients with respiratory-motion-induced artifacts on BH images.

Can Nuclear Imaging Techniques Predict Patient Outcome and Guide Medical Management in Hereditary Transthyretin Cardiac Amyloidosis?

PURPOSE OF REVIEW: Nuclear imaging recently gained a key role in the diagnosis and prognostic assessment of transthyretin (TTR)-related cardiac amyloidosis. This review aims at summarizing the state-of-the art regarding the implementation of nuclear imaging in the management of hereditary mutated TTR-cardiac amyloidosis (mTTR-CA). RECENT FINDINGS: Although cardiac uptake of bone tracers is acknowledged as a specific marker of TTR amyloid cardiac burden, recent studies validated the implementation of bone scan in the flow chart for non-invasive diagnosis and follow-up of CA in multicenter trials. Simultaneously, cardiac denervation evidenced by MIBG scintigraphy proved to be a strong and independent prognostic marker of poor outcome in mTTR-CA. By its unique ability to assess both amyloid burden and cardiac denervation, nuclear imaging may prove useful as part of multimodality imaging tools to trigger treatment initiation and monitoring in patients with mTTR-CA.

Uterine intravascular lymphoma as a cause of fever of unknown origin.

Primary intravascular large B cell lymphoma (IVL) remains a diagnostic challenge because of non-specific clinical, laboratory and imaging findings. The aim of the study was to analyse the major characteristics of IVL with uterine involvement. We retrospectively collected features of IVL with uterine involvement that was proven histologically or demonstrated by significant 18FDG uptake on 18FDG-PET/CT. Findings were compared to a comprehensive literature review. Five patients were identified. All of them were admitted for fever of unknown origin (FUO), with haemophagocytic lymphohistiocytosis in three cases. None had gynaecological symptom, contrasting with the literature data. Structural imaging (including whole-body CT scan and pelvic RMI) failed to yield any diagnosis. 18FDG-PET/CT showed intense uterine uptake in all cases. Endometrial biopsy was performed in three cases and was positive in one. Diagnosis was obtained from coelioscopic iliac adenopathy biopsy in one case and from total hysterectomy in another. Punch biopsy of skin lesions led to diagnosis in the two remaining cases. Bone marrow biopsy was normal in all cases. Clinicians should be aware of potential isolated uterine involvement in IVL, especially in elderly women with FUO. Normal structural imaging does not rule out the diagnosis and 18FDG-TEP/CT should be performed to guide high-yielding biopsy.

Use of self-gated radial cardiovascular magnetic resonance to detect and classify arrhythmias (atrial fibrillation and premature ventricular contraction).

BACKGROUND: Arrhythmia can significantly alter the image quality of cardiovascular magnetic resonance (CMR); automatic detection and sorting of the most frequent types of arrhythmias during the CMR acquisition could potentially improve image quality. New CMR techniques, such as non-Cartesian CMR, can allow self-gating: from cardiac motion-related signal changes, we can detect cardiac cycles without an electrocardiogram. We can further use this data to obtain a surrogate for RR intervals (valley intervals: VV). Our purpose was to evaluate the feasibility of an automated method for classification of non-arrhythmic (NA) (regular cycles) and arrhythmic patients (A) (irregular cycles), and for sorting of common arrhythmia patterns between atrial fibrillation (AF) and premature ventricular contraction (PVC), using the cardiac motion-related signal obtained during self-gated free-breathing radial cardiac cine CMR with compressed sensing reconstruction (XD-GRASP). METHODS: One hundred eleven patients underwent cardiac XD-GRASP CMR between October 2015 and February 2016; 33 were included for retrospective analysis with the proposed method (6 AF, 8 PVC, 19 NA; by recent ECG). We analyzed the VV, using pooled statistics (histograms) and sequential analysis (Poincaré plots), including the median (medVV), the weighted mean (meanVV), the total number of VV values (VVval), and the total range (VVTR) and half range (VVHR) of the cumulative frequency distribution of VV, including the median to half range (medVV/VVHR) and the half range to total range (VVHR/VVTR) ratios. We designed a simple algorithm for using the VV results to differentiate A from NA, and AF from PVC. RESULTS: Between NA and A, meanVV, VVval, VVTR, VVHR, medVV/VVHR and VVHR/VVTR ratios were significantly different (p values = 0.00014, 0.0027, 0.000028, 5×10-9, 0.002, respectively). Between AF and PVC, meanVV, VVval and medVV/VVHR ratio were significantly different (p values = 0.018, 0.007, 0.044, respectively). Using our algorithm, sensitivity, specificity, and accuracy were 93 %, 95 % and 94 % to discriminate between NA and A, and 83 %, 71 %, and 77 % to discriminate between AF and PVC, respectively; areas under the ROC curve were 0.93 and 0.89. CONCLUSIONS: Our study shows we can reliably detect arrhythmias and differentiate AF from PVC, using self-gated cardiac cine XD-GRASP CMR.

Comparison between tafamidis and liver transplantation as first-line therapy for hereditary transthyretin amyloidosis.

BACKGROUND: By stabilizing transthyretin, tafamidis delays progression of amyloidosis due to transthyretin variant (ATTRv) and replaced liver transplantation (LT) as the first-line therapy. No study compared these two therapeutic strategies. METHODS: In a monocentric retrospective cohort analysis, patients with ATTRv amyloidosis treated with either tafamidis or LT were compared using a propensity score and a competing risk analysis for three endpoints: all-cause mortality, cardiac worsening (heart failure or cardiovascular death) and neurological worsening (worsening in PolyNeuropathy Disability score). RESULTS: 345 patients treated with tafamidis (n = 129) or LT (n = 216) were analyzed, and 144 patients were matched (72 patients in each group, median age 54 years, 60% carrying the V30M mutation, 81% of stage I, 69% with cardiac involvement, median follow-up: 68 months). Patients treated with tafamidis had longer survival than LT patients (HR: 0.35; p = .032). Conversely, they also presented a 3.0-fold higher risk of cardiac worsening and a 7.1-fold higher risk of neurological worsening (p = .0071 and p < .0001 respectively). CONCLUSIONS: ATTRv amyloidosis patients treated with tafamidis would present a better survival but also a faster deterioration of their cardiac and neurological statuses as compared with LT. Further studies are needed to clarify the therapeutic strategy in ATTRv amyloidosis.

Squamous cell carcinoma of the tongue with cardiac metastasis on 18F-FDG PET/CT: A case report and literature review.

INTRODUCTION: The most common malignancies metastasizing to the heart are cancers of the lung, breast, mesothelioma, melanoma, leukemia, and lymphoma. Cardiac metastasis from a tongue cancer is a rare finding and only a few cases have been reported previously in the literature. In this case report and literature review, we discuss the main clinical features of patients with cardiac metastases secondary to a tongue cancer and imaging modalities performed, especially the 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). PATIENT CONCERNS: This is a case of a 39-year-old woman who in April 2018 was diagnosed with an invasive well differentiated squamous cell carcinoma of the movable tongue. She underwent a left hemiglossectomy followed by a revision of hemiglossectomy and ipsilateral selective neck lymph nodes dissection levels II to III because of pathological margins. An early inoperable clinical recurrence was diagnosed and she received radiochemotherapy with good clinical and metabolic response. She remained asymptomatic thereafter. DIAGNOSIS: In January 2020, a pre-scheduled 18F-FDG PET/CT showed a diffuse cardiac involvement. In February 2020, a biopsy of the lesion revealed a metastatic squamous cell carcinoma. INTERVENTIONS: She was deemed to not be a cardiac surgical candidate and treated by palliative chemotherapy: taxol-carboplatin associated with cetuximab then cetuximab alone because of adverse effects. A re-evaluation imaging performed in April 2020 evidenced a progression of the cardiac involvement, which led to switch chemotherapy by immunotherapy with nivolumab. OUTCOMES: This patient had a very poor prognosis and succumbed to major heart failure 4 months after the diagnosis of cardiac metastasis. CONCLUSION: In this case report, 18F-FDG PET/CT proved to be useful in detecting cardiac metastasis and changed the therapeutic management of the patient. It suggests that patients with tongue malignancies in a context of poor initial prognosis should be followed-up early by 18F-FDG PET/CT with HFLC diet to facilitate detection of recurrence.

Diffuse Hypermetabolic Bone Marrow Infiltration in Severe Primary Hyperoxaluria on FDG PET.

A 24-year-old man, with type 1 primary hyperoxaluria (diagnosed at age 20 years after repeated renal lithiasis, due to a I244T mutation frequently encountered in Mediterranean countries) complicated by end-stage renal failure requiring dialysis, was admitted for pancytopenia, refractory to erythropoietin injections. On clinical examination, he presented a hepatosplenomegaly without palpable adenopathy. F-FDG PET/CT revealed intense and diffuse bone marrow uptake in the axial skeleton and preferential long bone metaphyseal uptake. Bone marrow aspiration showed Gaucher-like cells infiltration due to oxalate accumulation in macrophages, leading to the diagnosis of bone marrow involvement by primary hyperoxaluria.

Current Status of Myocardial Perfusion Imaging With New SPECT/CT Cameras.

Myocardial perfusion imaging (MPI) with Single-Photon Emission Computed Tomography (SPECT) has a major role in the management of coronary artery disease. Recent technological advances regarding SPECT detectors with the use of solid-state detectors has allowed for improved imaging quality since a decade with dramatic dose and/or time reduction of imaging protocols due to improved sensitivity and spatial resolution, and is now performed as a routine exam. Interestingly, this new technology has modified our everyday practice, from acquisition protocols (low dose and ultra-fast protocols) to image semiology. Numerous studies have shown how these technical advances have allowed for improved patient management, with similar or improved diagnostic and prognostic information derived from MPI. These improvements have also led to the straightforward implementation of myocardial blood flow measurement. This article reviews the current status of MPI using new SPECT and SPECT/CT cameras.

18F-FDG PET/CT in bone sarcoidosis: an observational study.

OBJECTIVE: Bone sarcoidosis is usually rare. Imaging procedures such as fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can reveal bone sarcoidosis with better sensitivity than conventional radiography. We aimed to describe bone sarcoidosis involvement detected with 18F-FDG PET/CT. METHODS: This was an observational retrospective study of individuals with pulmonary sarcoidosis who underwent 18F-FDG PET/CT. According to the ATS/ERS/WASOG criteria, sarcoidosis was diagnosed by the presence of clinical and/or imaging features of sarcoidosis and evidence of non-caseating epithelioid granulomas on a biopsy. We assessed clinical and 18F-FDG PET/CT characteristics. RESULTS: Data for 85 patients with sarcoidosis (56.5% female, median age 47 [range 21-80] years) were analyzed. The median follow-up was 4 years. Among 56 patients, sarcoidosis occurred in more than three organs. According to ATS/ERS/WASOG criteria, bone sarcoidosis was diagnosed in 12 (14%) patients. The spine was the most commonly affected location (92%, n = 11), followed by the pelvis (67%, n = 8), sternum (33%, n = 4), humerus (25%, n = 3), and fingers (17%, n = 2). Only peripheral adenopathy was associated with bone sarcoidosis (p = 0.04). Seven patients had a 18F-FDG PET/CT follow-up, all showing a decrease of bone lesions. CONCLUSION: Bone sarcoidosis occurred in 14% of patients with sarcoidosis, affecting multiple bones and mostly the axial skeleton. 18F-FDG PET/CT seems a sensitive tool for diagnosis and follow-up of bone sarcoidosis.

Dose Reduction in Brain [18F]FDG PET/MRI: Give It Half a Chance.

PURPOSE: Integrated positron emission tomography (PET)/magnetic resonance imaging (MRI) offers promising tools for evaluating brain disorders, including the minimization of exposure to ionizing radiation. Considering the length of scanning time with PET/MRI systems and their high sensitivity, we assumed that the activity could be reduced by one half compared with recommended activity for brain 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) PET exams without degrading image quality. PROCEDURES: We retrospectively simulated the reduction of injected activity (1 vs. 2 MBq/kg, [18F]FDG) in 100 patients assessed for cognitive impairment with simultaneous PET/MRI imaging. A list-mode acquisition was used to generate a 20-min image set as a reference (PETSTD) and to simulate a low-dose injection with a 10-min image (PETLD). We tested the reproducibility between PETLD and PETSTD with a blinded visual interpretation by two nuclear physicians asked to classify metabolic patterns, and a quantitative analysis conducted with regions-of-interest. Voxelwise comparisons between patients suggestive of Alzheimer's disease (AD) and frontotemporal dementia (FTD) were also conducted. RESULTS: The intra-operator agreement was high between the PETSTD and PETLD visual assessments for both readers (kappa 0.92 and 0.99). SUV ratios were strongly reproducible (intraclass correlation coefficient 0.95). The voxelwise and regional comparisons between AD vs. FTD metabolic profiles yielded very similar results with PETSTD and PETLD. CONCLUSIONS: A reduction of the [18F]FDG dose down to 1 MBq/kg is possible when performing 20-min brain PET/MRI without modifying diagnostic performance and quantitative assessments. The advantage is a significant reduction in the patient effective dose, which is non-negligible in longitudinal follow-up studies and in research protocols involving healthy volunteers.

Persistent FDG/PET CT uptake in idiopathic retroperitoneal fibrosis helps identifying patients at a higher risk for relapse.

BACKGROUND: The aim of this study was to evaluate the prognostic value of persistent retroperitoneal fibrosis FDG uptake using FDG/PET CT in patients with idiopathic retroperitoneal fibrosis (IRF). METHODS: In this monocentric retrospective cohort study, all patients admitted for IRF from January 2009 to December 2017 underwent a FDG/PET CT at diagnosis and during follow up. Metabolic activity of IRF was assessed by retroperitoneal fibrosis FDG uptake measured as maximal standardized uptake value (SUVmax). The primary outcome was IRF relapse rate during follow-up. RESULTS: 23 consecutive patients (54.7 [36.9-89] years, 73.9% of men) diagnosed with IRF had FDG/PET CT imaging performed at diagnosis, 3.1 [1-8.7] months (i.e 1st evaluation) and 10.4 [4.9-17.5] months (i.e 2nd evaluation) after diagnosis. High FDG retroperitoneal fibrosis uptake was present in all patients at diagnosis (SUVmax 6.5 [3.8-11.9]) and persisted in 16 (69.6%; SUVmax 3.65 [2.1-5.4]) and 12 (52.2%; SUVmax 3.75 [2.7-7.8]) patients, at 1st and 2nd evaluation respectively. All but one patient had received steroids at IRF diagnosis and 21 (91.3%) were in complete remission at both 1st and 2nd evaluation. During a median follow-up period of 38.7 [3-106.9] months, 6 (26.1%) patients suffered IRF relapse that occurred 15.7 [9.2-42.8] months after diagnosis. Multivariate analysis showed that only persistent retroperitoneal fibrosis FDG uptake at 2nd evaluation was associated with IRF relapse (p = .046). CONCLUSIONS: In IRF, persistent retroperitoneal fibrosis FDG uptake during follow up is associated with clinical outcome. FDG/PET CT may help to better stratify the risk of relapse and target therapy in IRF.

Nuclear Imaging in Sarcoidosis.

Sarcoidosis is a multisystem granulomatosis which may result in a wide variety of clinical and biological presentations. Symptoms are often nonspecific, and incidental abnormal findings on chest radiography is rather common. Although sarcoidosis resolves favorably in most cases, some localizations can provoke functional impairment or even impact on patients' prognosis. The diagnosis is based on a pathological hallmark which is the non-necrotizing epithelioid-cell rich granuloma. Owing to the ability to detect inflammation throughout the body with a high sensibility, FDG-PET/CT gained a central role in sarcoidosis because it can suggest the diagnosis in certain clinical context, guide biopsy, evaluate the extent of the disease, help assess the prognosis, and monitor immunosuppressive therapy. This review will briefly describe clinical and typical findings of conventional imaging according to organ involvement, in order to highlight the additional information provided by nuclear imaging. In the future, we can expect to further improve diagnostic performance of imaging in some indications through the availability of more specific radiopharmaceuticals and the wider use of combined PET/MRI.

Increased 18F-FDG Uptake in Lhermitte-Duclos Disease With Cowden Syndrome Revealed by PET-MRI.

A 62-year-old woman, with the history of breast and colorectal cancer, presented intermittent diplopia. A cerebellar lesion was revealed by F-FDG PET-MRI without post-gadolinium enhancement, but with increased perfusion and strong F-FDG uptake. The diagnosis of Cowden syndrome with PTEN gene mutation, linked to higher risk of neoplasia and occurrence of hamartomatous lesions characteristic of the Lhermitte-Duclos disease (LDD), was confirmed by genetic investigation.

Multi-cycle Reconstruction of Cardiac MRI for the Analysis of Inter-ventricular Septum Motion During Free Breathing.

Small variations in left-ventricular preload due to respiration produce measurable changes in cardiac function in normal subjects. We show that this mechanism is altered in patients with reduced ejection fraction (EF), hypertrophy, or volume-loaded right ventricle (RV). We propose a multi-dimensional retrospective image reconstruction, based on an adaptive, soft classification of data into respiratory and cardiac phases, to study these effects.

Cardiovascular magnetic resonance features of mechanical dyssynchrony in patients with left bundle branch block.

Patients with left bundle branch block (LBBB) can exhibit mechanical dyssynchrony which may contribute to heart failure; such patients may benefit from cardiac resynchronization treatment (CRT). While cardiac magnetic resonance imaging (CMR) has become a common part of heart failure work-up, CMR features of mechanical dyssynchrony in patients with LBBB have not been well characterized. This study aims to investigate the potential of CMR to characterize mechanical features of LBBB. CMR examinations from 43 patients with LBBB on their electrocardiogram, but without significant focal structural abnormalities, and from 43 age- and gender-matched normal controls were retrospectively reviewed. The following mechanical features of LBBB were evaluated: septal flash (SF), apical rocking (AR), delayed aortic valve opening measured relative to both end-diastole (AVOED) and pulmonic valve opening (AVOPVO), delayed left-ventricular (LV) free-wall contraction, and curvatures of the septum and LV free-wall. Septal displacement curves were also generated, using feature-tracking techniques. The echocardiographic findings of LBBB were also reviewed in those subjects for whom they were available. LBBB was significantly associated with the presence of SF and AR; within the LBBB group, 79 % had SF and 65 % had AR. Delayed AVOED, AVOPVO, and delayed LV free-wall contraction were significantly associated with LBBB. AVOED and AVOPVO positively correlated with QRS duration and negatively correlated with ejection fraction. Hearts with electrocardiographic evidence of LBBB showed lower septal-to-LV free-wall curvature ratios at end-diastole compared to normal controls. CMR can be used to identify and evaluate mechanical dyssynchrony in patients with LBBB. None of the normal controls showed the mechanical features associated with LBBB. Moreover, not all patients with LBBB showed the same degree of mechanical dyssynchrony, which could have implications for CRT.