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Purpose To use unsupervised machine learning to identify phenotypic clusters with increased risk of arrhythmic mitral valve prolapse (MVP). Materials and Methods This retrospective study included patients with MVP without hemodynamically significant mitral regurgitation or left ventricular (LV) dysfunction undergoing late gadolinium enhancement (LGE) cardiac MRI between October 2007 and June 2020 in 15 European tertiary centers. The study end point was a composite of sustained ventricular tachycardia, (aborted) sudden cardiac death, or unexplained syncope. Unsupervised data-driven hierarchical k-mean algorithm was utilized to identify phenotypic clusters. The association between clusters and the study end point was assessed by Cox proportional hazards model. Results A total of 474 patients (mean age, 47 years ± 16 [SD]; 244 female, 230 male) with two phenotypic clusters were identified. Patients in cluster 2 (199 of 474, 42%) had more severe mitral valve degeneration (ie, bileaflet MVP and leaflet displacement), left and right heart chamber remodeling, and myocardial fibrosis as assessed with LGE cardiac MRI than those in cluster 1. Demographic and clinical features (ie, symptoms, arrhythmias at Holter monitoring) had negligible contribution in differentiating the two clusters. Compared with cluster 1, the risk of developing the study end point over a median follow-up of 39 months was significantly higher in cluster 2 patients (hazard ratio: 3.79 [95% CI: 1.19, 12.12], P = .02) after adjustment for LGE extent. Conclusion Among patients with MVP without significant mitral regurgitation or LV dysfunction, unsupervised machine learning enabled the identification of two phenotypic clusters with distinct arrhythmic outcomes based primarily on cardiac MRI features. These results encourage the use of in-depth imaging-based phenotyping for implementing arrhythmic risk prediction in MVP. Keywords: MR Imaging, Cardiac, Cardiac MRI, Mitral Valve Prolapse, Cluster Analysis, Ventricular Arrhythmia, Sudden Cardiac Death, Unsupervised Machine Learning Supplemental material is available for this article. © RSNA, 2024.
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Prolapso de la Válvula Mitral , Fenotipo , Aprendizaje Automático no Supervisado , Humanos , Prolapso de la Válvula Mitral/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sistema de Registros , Imagen por Resonancia Cinemagnética/métodos , Arritmias Cardíacas/diagnóstico por imagen , Arritmias Cardíacas/fisiopatología , Adulto , Imagen por Resonancia MagnéticaRESUMEN
Background Patients with mitral valve prolapse (MVP) may develop adverse outcomes even in the absence of mitral regurgitation or left ventricular (LV) dysfunction. Purpose To investigate the prognostic value of mitral annulus disjunction (MAD) and myocardial fibrosis at late gadolinium enhancement (LGE) cardiac MRI in patients with MVP without moderate-to-severe mitral regurgitation or LV dysfunction. Materials and Methods In this longitudinal retrospective study, 118 144 cardiac MRI studies were evaluated between October 2007 and June 2020 at 15 European tertiary medical centers. Follow-up was from the date of cardiac MRI examination to June 2020; the minimum and maximum follow-up intervals were 6 months and 156 months, respectively. Patients were excluded if at least one of the following conditions was present: cardiomyopathy, LV ejection fraction less than 40%, ischemic heart disease, congenital heart disease, inflammatory heart disease, moderate or worse mitral regurgitation, participation in competitive sport, or electrocardiogram suggestive of channelopathies. In the remainder, cardiac MRI studies were reanalyzed, and patients were included if they were aged 18 years or older, MVP was diagnosed at cardiac MRI, and clinical information and electrocardiogram monitoring were available within 3 months from cardiac MRI examination. The end point was a composite of adverse outcomes: sustained ventricular tachycardia (VT), sudden cardiac death (SCD), or unexplained syncope. Multivariable Cox regression analysis was performed. Results A total of 474 patients (mean age, 47 years ± 16 [SD]; 244 women) were included. Over a median follow-up of 3.3 years, 18 patients (4%) reached the study end point. LGE presence (hazard ratio, 4.2 [95% CI: 1.5, 11.9]; P = .006) and extent (hazard ratio, 1.2 per 1% increase [95% CI: 1.1, 1.4]; P = .006), but not MAD presence (P = .89), were associated with clinical outcome. LGE presence had incremental prognostic value over MVP severity and sustained VT and aborted SCD at baseline (area under the receiver operating characteristic curve, 0.70 vs 0.62; P = .03). Conclusion In contrast to mitral annulus disjunction, myocardial fibrosis determined according to late gadolinium enhancement at cardiac MRI was associated with adverse outcome in patients with mitral valve prolapse without moderate-to-severe mitral regurgitation or left ventricular dysfunction. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Gerber in this issue.
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Cardiomiopatías , Insuficiencia de la Válvula Mitral , Prolapso de la Válvula Mitral , Disfunción Ventricular Izquierda , Humanos , Femenino , Persona de Mediana Edad , Prolapso de la Válvula Mitral/complicaciones , Estudios Retrospectivos , Medios de Contraste , Gadolinio , Válvula Mitral , Imagen por Resonancia Magnética , Fibrosis , Muerte Súbita CardíacaRESUMEN
BACKGROUND: Patients with mitochondrial diseases are at risk of heart failure (HF) and arrhythmic major adverse cardiac events (MACE). OBJECTIVES: We developed prediction models to estimate the risk of HF and arrhythmic MACE in this population. METHODS: We determined the incidence and searched for predictors of HF and arrhythmic MACE using Cox regression in 600 adult patients from a multicenter registry with genetically confirmed mitochondrial diseases. RESULTS: Over a median follow-up time of 6.67 years, 29 patients (4.9%) reached the HF endpoint, including 19 hospitalizations for nonterminal HF, 2 cardiac transplantations, and 8 deaths from HF. Thirty others (5.1%) reached the arrhythmic MACE, including 21 with third-degree or type II second-degree atrioventricular blocks, 4 with sinus node dysfunction, and 5 sudden cardiac deaths. Predictors of HF were the m.3243A>G variant (HR: 4.3; 95% CI: 1.8-10.1), conduction defects (HR: 3.0; 95% CI: 1.3-6.9), left ventricular (LV) hypertrophy (HR: 2.6; 95% CI: 1.1-5.8), LV ejection fraction <50% (HR: 10.2; 95% CI: 4.6-22.3), and premature ventricular beats (HR: 4.1; 95% CI: 1.7-9.9). Independent predictors for arrhythmia were single, large-scale mtDNA deletions (HR: 4.3; 95% CI: 1.7-10.4), conduction defects (HR: 6.8; 95% CI: 3.0-15.4), and LV ejection fraction <50% (HR: 2.7; 95% CI: 1.1-7.1). C-indexes of the Cox regression models were 0.91 (95% CI: 0.88-0.95) and 0.80 (95% CI: 0.70-0.90) for the HF and arrhythmic MACE, respectively. CONCLUSIONS: We developed the first prediction models for HF and arrhythmic MACE in patients with mitochondrial diseases using genetic variant type and simple cardiac assessments.
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Insuficiencia Cardíaca , Enfermedades Mitocondriales , Adulto , ADN Mitocondrial/genética , Corazón , Insuficiencia Cardíaca/epidemiología , Humanos , Hipertrofia Ventricular Izquierda , Enfermedades Mitocondriales/complicaciones , Enfermedades Mitocondriales/epidemiología , Enfermedades Mitocondriales/genética , Pronóstico , Factores de Riesgo , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
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.
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BACKGROUND: Hereditary or variant transthyretin amyloidosis (ATTRv) is a progressive disease manifesting with neuropathy and/or cardiomyopathy. An early and accurate diagnosis of cardiac amyloidosis is a pre-requisite for timely and appropriate patient management, including anti-amyloid therapies, as it is associated with heart failure, conduction disease, and arrhythmias, leading to reduced quality of life and early death. CASE SUMMARY: We present the case of an ATTRv male patient presenting with a mixed amyloidosis phenotype (neuropathy and cardiomyopathy). Cardiac disease manifestation comprised tachyarrhythmias (atrial fibrillation) and conduction abnormalities (atrio-ventricular block) in addition to segmental left ventricular (LV) hypertrophy (septal wall) due to regionally pronounced amyloid deposits in the basal LV myocardium. Interestingly, by means of serial cardiovascular magnetic resonance (CMR) studies, we were able to demonstrate an impressive and unexpected improvement of cardiomyopathy findings within a relatively short period-of-time after the implementation of genome-silencer therapies. DISCUSSION: This is our second case report that showed ATTRv cardiomyopathy reversal under anti-amyloid therapy-documented by multi-parametric CMR. Our findings support the hypothesis that amyloid infiltration leading to cardiomyopathy is not an irreversible pathological process-but rather a dynamic one, that cannot only be stopped but even reversed (to a certain degree) by currently emerging anti-amyloid therapies. Moreover, the role of serial multi-parametric CMR imaging for surveillance of cardiomyopathy dynamics under these therapies is nicely illustrated.
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AIMS: Dilated cardiomyopathy (DCM) associated with dystrophin gene (DMD) mutations in individuals with mild or absent skeletal myopathy is often indistinguishable from other DCM forms. We sought to describe the phenotype and prognosis of DMD associated DCM in DMD mutation carriers without severe skeletal myopathy. METHODS AND RESULTS: At 26 European centres, we retrospectively collected clinical characteristics and outcomes of 223 DMD mutation carriers (83% male, 33 ± 15 years). A total of 112 individuals (52%) had DCM at first evaluation [n = 85; left ventricular ejection fraction (LVEF) 34 ± 11.2%] or developed DCM (n = 27; LVEF 41.3 ± 7.5%) after a median follow-up of 96 months (interquartile range 5-311 months). DCM penetrance was 45% in carriers older than 40 years. DCM appeared earlier in males and was independent of the type of mutation, presence of skeletal myopathy, or elevated serum creatine kinase levels. Major adverse cardiac events (MACE) occurred in 22% individuals with DCM, 18% developed end-stage heart failure and 9% sudden cardiac death or equivalent. Skeletal myopathy was not associated with survival free of MACE in patients with DCM. Decreased LVEF and increased left ventricular end-diastolic diameter at baseline were associated with MACE. Individuals without DCM had favourable prognosis without MACE or death during follow-up. CONCLUSIONS: DMD-associated DCM without severe skeletal myopathy is characterized by incomplete penetrance but high risk of MACE, including progression to end-stage heart failure and ventricular arrhythmias. DCM onset is the major determinant of prognosis with similar survival regardless of the presence of skeletal myopathy.
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Cardiomiopatía Dilatada , Insuficiencia Cardíaca , Enfermedades Musculares , Adolescente , Adulto , Cardiomiopatía Dilatada/epidemiología , Cardiomiopatía Dilatada/genética , Distrofina/genética , Femenino , Insuficiencia Cardíaca/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda , Adulto JovenRESUMEN
BACKGROUND AND OBJECTIVE: The clinical relevance and interrelation of sleep-disordered breathing and nocturnal hypoxemia in patients with precapillary pulmonary hypertension (PH) is not fully understood. METHODS: Seventy-one patients with PH (age 63 ± 15 years, 41% male) and 35 matched controls were enrolled. Patients with PH underwent clinical examination with assessment of sleep quality, daytime sleepiness, 6-minute walk distance (6MWD), overnight cardiorespiratory polygraphy, lung function, hypercapnic ventilatory response (HCVR; by rebreathing technique), amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac MRI (n = 34). RESULTS: Prevalence of obstructive sleep apnea (OSA) was 68% in patients with PH (34% mild, apnea-hypopnea index [AHI] ≥5 to <15/h; 34% moderate to severe, AHI ≥15/h) versus 5% in controls (p < 0.01). Only 1 patient with PH showed predominant central sleep apnea (CSA). Nocturnal hypoxemia (mean oxygen saturation [SpO2] <90%) was present in 48% of patients with PH, independent of the presence of OSA. There were no significant differences in mean nocturnal SpO2, self-reported sleep quality, 6MWD, HCVR, and lung and cardiac function between patients with moderate to severe OSA and those with mild or no OSA (all p > 0.05). Right ventricular (RV) end-diastolic (r = -0.39; p = 0.03) and end-systolic (r = -0.36; p = 0.04) volumes were inversely correlated with mean nocturnal SpO2 but not with measures of OSA severity or daytime clinical variables. CONCLUSION: OSA, but not CSA, is highly prevalent in patients with PH, and OSA severity is not associated with nighttime SpO2, clinical and functional status. Nocturnal hypoxemia is a frequent finding and (in contrast to OSA) relates to structural RV remodeling in PH.
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Hipertensión Pulmonar , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Anciano , Femenino , Humanos , Hipertensión Pulmonar/complicaciones , Hipoxia/diagnóstico , Hipoxia/epidemiología , Hipoxia/etiología , Masculino , Persona de Mediana Edad , Polisomnografía , Prevalencia , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
BACKGROUND: Coronary microvascular dysfunction (CMD) is present in various non-ischemic cardiomyopathies and in particular in those with left-ventricular hypertrophy. This study evaluated the diagnostic value of the novel cardiovascular magnetic resonance (CMR) parameter "myocardial transit-time" (MyoTT) in distinguishing cardiac amyloidosis from other hypertrophic cardiomyopathies. METHODS: N = 20 patients with biopsy-proven cardiac amyloidosis (CA), N = 20 patients with known hypertrophic cardiomyopathy (HCM), and N = 20 control patients without relevant cardiac disease underwent dedicated CMR studies on a 1.5-T MR scanner. The CMR protocol comprised cine and late-gadolinium-enhancement (LGE) imaging as well as first-pass perfusion acquisitions at rest for MyoTT measurement. MyoTT was defined as the blood circulation time from the orifice of the coronary arteries to the pooling in the coronary sinus (CS) reflecting the transit-time of gadolinium in the myocardial microvasculature. RESULTS: MyoTT was significantly prolonged in patients with CA compared to both groups: 14.8 ± 4.1 s in CA vs. 12.2 ± 2.5 s in HCM (p = 0.043) vs. 7.2 ± 2.6 s in controls (p < 0.001). Native T1 and extracellular volume (ECV) were significantly higher in CA compared to HCM and controls (p < 0.001). Both parameters were associated with a higher diagnostic accuracy in predicting the presence of CA compared to MyoTT: area under the curve (AUC) for native T1 = 0.93 (95% confidence interval (CI) = 0.83-1.00; p < 0.001) and AUC for ECV = 0.95 (95% CI = 0.88-1.00; p < 0.001)-compared to the AUC for MyoTT = 0.76 (95% CI = 0.60-0.92; p = 0.008). In contrast, MyoTT performed better than all other CMR parameters in differentiating HCM from controls (AUC for MyoTT = 0.93; 95% CI = 0.81-1.00; p = 0.003 vs. AUC for native T1 = 0.69; 95% CI = 0.44-0.93; p = 0.20 vs. AUC for ECV = 0.85; 95% CI = 0.66-1.00; p = 0.017). CONCLUSION: The relative severity of CMD (measured by MyoTT) in relationship to extracellular changes (measured by native T1 and/or ECV) is more pronounced in HCM compared to CA-in spite of a higher absolute MyoTT value in CA patients. Hence, MyoTT may improve our understanding of the interplay between extracellular/intracellular and intravasal changes that occur in the myocardium during the disease course of different cardiomyopathies.
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Amiloidosis/diagnóstico , Cardiomiopatía Hipertrófica/diagnóstico , Vasos Coronarios/patología , Imagen por Resonancia Cinemagnética/métodos , Microvasos/patología , Miocardio/patología , Función Ventricular Izquierda/fisiología , Amiloidosis/fisiopatología , Biopsia , Cardiomiopatías/diagnóstico , Cardiomiopatías/fisiopatología , Cardiomiopatía Hipertrófica/fisiopatología , Circulación Coronaria/fisiología , Estudios de Seguimiento , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de TiempoRESUMEN
BACKGROUND: Cardiovascular magnetic resonance (CMR) studies in patients with implanted cardioverter/defibrillators (ICD) are increasingly required in daily clinical practice. However, the clinical experience regarding the feasibility as well as clinical value of CMR studies in patients with subcutaneous ICD (S-ICD) is still limited. Besides safety issues, image quality and analysis can be impaired primarily due the presence of image artefacts associated with the generator. METHODS: Twenty-three patients with an implanted S-ICD (EMBLEM, Boston Scientific, Marlborough, Massachusetts, USA; MR-conditional) with suspected cardiomyopathy and/or myocarditis underwent multi-parametric CMR imaging. Studies were performed on a 1.5 T CMR scanner after device interrogation and comprised standard a) balanced steady state free precession cine, b) T2 weighted-edema, c) velocity-encoded cine flow, d) myocardial perfusion, e) late-gadolinium-enhancement (LGE)-imaging and f) 3D-CMR angiography of the aorta. In case of substantial artefacts, alternative CMR techniques such as spoiled gradient-echo cine-sequences and wide-band inversion-recovery LGE (wb-LGE) sequences were applied. RESULTS: Successful CMR studies could be performed in all patients without any case of unexpected early termination or relevant technical complication other than permanent loss of the S-ICD system beeper volume in 52% of our patients. Assessment of cine-CMR images was predominantly impaired in the left ventricular (LV) anterior, lateral and inferior wall segments and a switch to spoiled gradient echo-based cine-CMR allowed an accurate assessment of cine-images in N = 17 (74%) patients with only limited artefacts. Hyperintensity artefacts in conventional LGE-images were predominantly observed in the LV anterior, lateral and inferior wall segments and image optimisation by use of the wb-LGE was helpful in 15 (65%) cases. Aortic flow measurements and 3D-CMR angiography were assessable in all patients Perfusion imaging artefacts precluded a meaningful assessment in at least one half of the patients. A benefit in clinical-decision making was documented in 17 (74%) patients in the present study. CONCLUSION: Safe 1.5 T CMR imaging was possible in all patients with an S-ICD, though the majority had permanent loss of the S-ICD beeper volume. Achieving good image quality may be challenging in some patients - particularly for perfusion imaging. Using spoiled gradient echo-based cine-sequences and wb-LGE sequences may help to reduce the extent of artefacts, thereby allowing accurate cardiac assessment. Thus, 1.5 T CMR studies should not be withhold in patients with S-ICD for safety concerns and/or fear of extensive imaging artefacts precluding successful image analysis.
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Cardiomiopatías/diagnóstico por imagen , Desfibriladores Implantables , Cardioversión Eléctrica/instrumentación , Imagen por Resonancia Cinemagnética , Imagen de Perfusión Miocárdica/métodos , Miocarditis/diagnóstico por imagen , Adulto , Anciano , Artefactos , Cardiomiopatías/fisiopatología , Cardiomiopatías/terapia , Toma de Decisiones Clínicas , Circulación Coronaria , Cardioversión Eléctrica/efectos adversos , Femenino , Humanos , Imagen por Resonancia Cinemagnética/efectos adversos , Masculino , Persona de Mediana Edad , Imagen de Perfusión Miocárdica/efectos adversos , Miocarditis/fisiopatología , Miocarditis/terapia , Seguridad del Paciente , Valor Predictivo de las Pruebas , Pronóstico , Diseño de Prótesis , Falla de Prótesis , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Streptococcal pharyngitis is a common infection, with both suppurative and non-suppurative complications. Most importantly, a streptococcal infection can cause heart disease in different pathophysiological pathways. Acute non-rheumatic perimyocarditis appears to be a more frequent pathological entity associated with streptococcal pharyngitis as once thought, which is poorly understood and explored. CASE SUMMARY: We present the case of a middle-aged man with acute chest pain, electrocardiogram (ECG) abnormalities, and elevated cardiac enzymes following a recent episode of pharyngitis in which streptococcal-associated perimyocarditis was diagnosed. Cardiovascular magnetic resonance (CMR) imaging established the diagnosis and allowed cardiac disease monitoring after successful antibiotic therapy resulting in complete clinical recovery. DISCUSSION: Patients presenting with acute chest pain, ECG abnormalities, and cardiac enzyme elevations do not always suffer from an ischaemic heart attack. A thorough investigation comprising a detailed past medical history and non-invasive imaging such as CMR are the cornerstones for unravelling a correct diagnosis and implementing a proper treatment-as was shown in the present clinical case.
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BACKGROUND: Myocardial microvascular disease may occur during the disease course of different cardiac as well as systemic disorders. With the present study, we introduce a novel and easy-to-perform cardiovascular magnetic resonance (CMR) parameter named "myocardial transit-time" (MyoTT). METHODS: N = 20 patients with known hypertrophic cardiomyopathy (HCM) and N = 20 control patients without relevant cardiac disease underwent dedicated CMR studies on a 1.5-T MR scanner. The CMR protocol comprised cine and late-gadolinium-enhancement (LGE) imaging as well as first-pass perfusion acquisitions at rest for MyoTT measurement. MyoTT was defined as the blood circulation time from the orifice of the coronary arteries to the pooling in the coronary sinus (CS), and accordingly measured as the temporal difference between the appearances of CMR contrast agent in the aortic root and the CS reflecting the transit-time of gadolinium in the myocardial microvasculature. RESULTS: Patients with HCM had a significantly prolonged MyoTT compared to controls (11.0 (9.1-14.5) s vs. 6.5 (4.8-8.4) s, p < 0.001). This significant difference did not change when the individual heart rate was taken into consideration (MyoTT indexed, p < 0.001). Significant correlations were found between MyoTT and maximal left ventricular (LV) wall thickness (r = 0.771, p < 0.001), MyoTT and presence of LGE (r = 0.760, p < 0.001) as well as MyoTT and LV global longitudinal strain (r = 0.672, p < 0.001). ROC analysis resulted in an area-under-curve (AUC) of 0.90 for MyoTT and showed an optimal sensitivity/specificity cut-off of 7.85 s to differentiate HCM from controls. CONCLUSION: "Myocardial transit-time" is a novel and easy-to-perform CMR parameter that allows a quick assessment of the extent of myocardial microvascular disease. This novel CMR parameter may open new vistas in the assessment of microvascular disease-not only in HCM patients. Future studies will show the usefulness and clinical relevance of this novel CMR parameter.
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Cardiomiopatía Hipertrófica/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Circulación Coronaria , Imagen por Resonancia Cinemagnética , Microcirculación , Imagen de Perfusión Miocárdica , Compuestos Organometálicos/administración & dosificación , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Cardiomiopatía Hipertrófica/fisiopatología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de TiempoRESUMEN
Immune checkpoint inhibitors (ICIs) can induce immunity-related adverse events. We demonstrate the clinical use of cardiac magnetic resonance and endomyocardial biopsy in the diagnosis and subsequent monitoring of ICI-associated myocarditis, suggesting the need to establish and evaluate a cardiac monitoring protocol for patients under ICI therapy. (Level of Difficulty: Intermediate.).
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Interventional magnetic resonance imaging (MRI) procedures promise to open-up new vistas regarding clinically relevant diagnostic and/or therapeutic procedures in the field of cardiology. However, a number of major limitations and challenges regarding interventional cardiovascular magnetic resonance (CMR) procedures still delay their translation from pre-clinical studies to human application. A CMR-conditional cardiac phantom was constructed using MR-safe or -conditional materials only that is based on a unique modular composition allowing quick replacement of individual components. A maximal flow of 76 ml/sec in the aorta and 111 ml/sec in the pulmonary artery were measured, whereas the maximal flow velocity was 56 cm/sec and 89 cm/sec, respectively. A conventional wedge-pressure catheter was advanced over a MRI-conditional guidewire into the right ventricle and thereafter positioned in the pulmonary artery. Pulmonary artery pressure was measured, obtaining the following values for our cardiac phantom: max/min/mean = 16/10/12 mmHg. The presented CMR-conditional cardiac phantom is the first of its kind that does not only mimic cardiac mechanics with adjustable fluid pressure in a four chamber setup that is closely adapted to that of the human heart, but also enables introduction and testing of interventional tools such as guidewires and catheters.
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Cateterismo Cardíaco/métodos , Corazón/diagnóstico por imagen , Imagen por Resonancia Magnética Intervencional/métodos , Imagen por Resonancia Magnética/métodos , Arteria Pulmonar/diagnóstico por imagen , Femenino , Corazón/anatomía & histología , Ventrículos Cardíacos/anatomía & histología , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética Intervencional/instrumentación , Masculino , Fantasmas de Imagen , Valor Predictivo de las Pruebas , Arteria Pulmonar/anatomía & histología , Reproducibilidad de los ResultadosRESUMEN
Muscular dystrophies (MD) represent a heterogeneous group of rare genetic diseases that often lead to significant weakness due to progressive muscle degeneration. In many forms of MD, cardiac manifestations including heart failure, atrial and ventricular arrhythmias and conduction abnormalities can occur and may be a predominant feature of the disease. Cardiac magnetic resonance (CMR) can assess cardiac anatomy, global and regional ventricular function, volumes and mass as well as presence of myocardial inflammation, infiltration or fibrosis. The role for cardiac MRI has been well-established in a wide range of muscular dystrophies related cardiomyopathies. CMR is a more sensitive technique than echocardiography for early diagnosis of cardiac involvement. It has also great potential to improve the prediction of long-term outcome, particularly the development of heart failure and arrhythmic events; however it still has to be validated by longitudinal studies including large populations. This review will outline the utility of CMR in patients with muscular dystrophies for assessment of myocardial involvement, risk stratification, and in guiding therapeutic management.
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Arritmias Cardíacas/fisiopatología , Cardiomiopatías/fisiopatología , Distrofias Musculares/fisiopatología , Miocardio/patología , Cardiomiopatías/genética , Muerte Súbita Cardíaca , Humanos , Imagen por Resonancia Magnética/métodos , Distrofias Musculares/genéticaRESUMEN
Background: Several determinants of exercise intolerance in patients with precapillary pulmonary hypertension (PH) due to pulmonary arterial hypertension and/or chronic thromboembolic PH (CTEPH) have been suggested, including diaphragm dysfunction. However, these have rarely been evaluated in a multimodal manner. Methods: Forty-three patients with PH (age 58 ± 17 years, 30% male) and 43 age- and gender-matched controls (age 54 ± 13 years, 30% male) underwent diaphragm function (excursion and thickening) assessment by ultrasound, standard spirometry, arterial blood gas analysis, echocardiographic assessment of pulmonary artery pressure (PAP), assay of amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac magnetic resonance (CMR) imaging to evaluate right ventricular systolic ejection fraction (RVEF). Exercise capacity was determined using the 6-min walk distance (6MWD). Results: Excursion velocity during a sniff maneuver (SniffV, 4.5 ± 1.7 vs. 6.8 ± 2.3 cm/s, P<0.01) and diaphragm thickening ratio (DTR, 1.7 ± 0.5 vs. 2.8 ± 0.8, P<0.01) were significantly lower in PH patients versus controls. PH patients with worse exercise tolerance (6MWD <377 vs. ≥377 m) were characterized by worse SniffV, worse DTR, and higher NT-pro-BNP levels as well as by lower arterial carbon dioxide levels and RVEF, which were all univariate predictors of exercise limitation. On multivariate analysis, the only independent predictors of exercise limitation were RVEF (r = 0.47, P=0.001) and NT-proBNP (r = -0.27, P=0.047). Conclusion: Patients with PH showed diaphragm dysfunction, especially as exercise intolerance progressed. However, diaphragm dysfunction does not independently contribute to exercise intolerance, beyond what can be explained from right heart failure.