RESUMO
BACKGROUND: The endothelial nitric oxide synthase (eNOS) gene deficiency is known to cause impaired coronary vasodilating capability in animal models. In the general clinical population, the eNOS gene polymorphisms, able to affect eNOS activity, were associated with cardiometabolic risk features and prevalence of coronary artery disease (CAD). AIM: To investigate the association of eNOS Glu298Asp gene polymorphism, cardiometabolic profile, obstructive CAD and inducible myocardial ischemia in patients with suspected stable CAD. METHODS: A total of 506 patients (314 males; mean age 62 ± 9 years) referred for suspected CAD was enrolled. Among these, 325 patients underwent stress ECG or cardiac imaging to assess the presence of inducible myocardial ischemia and 436 patients underwent non-invasive computerized tomography or invasive coronary angiography to assess the presence of obstructive CAD. Clinical characteristics and blood samples were collected for each patient. RESULTS: In the whole population, 49.6% of patients were homozygous for the Glu298 genotype (Glu/Glu), 40.9% heterozygotes (Glu/Asp) and 9.5% homozygous for the 298Asp genotype (Asp/Asp). Obstructive CAD was documented in 178/436 (40.8%) patients undergoing coronary angiography while myocardial ischemia in 160/325 (49.2%) patients undergoing stress testing. Patients with eNOS Asp genotype (Glu/Asp + Asp/Asp) had no significant differences in clinical risk factors and in circulating markers. Independent predictors of obstructive CAD were age, gender, obesity, and low HDL-C. Independent predictors of myocardial ischemia were gender, obesity, low HDL-C and Asp genotype. In the subpopulation in which both stress tests and coronary angiography were performed, the Asp genotype remained associated with increased myocardial ischemia risk after adjustment for obstructive CAD. CONCLUSION: In this population, low-HDL cholesterol was the only cardiometabolic risk determinant of obstructive CAD. The eNOS Glu298Asp gene polymorphism was significantly associated with inducible myocardial ischemia independently of other risk factors and presence of obstructive CAD.
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Doença da Artéria Coronariana , Isquemia Miocárdica , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Artérias , HDL-Colesterol , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/genética , Genótipo , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/genética , Óxido Nítrico Sintase Tipo III/genética , Obesidade , Polimorfismo Genético , Fatores de RiscoRESUMO
OBJECTIVE: We established normal ranges for native T1 and T2 values in the human liver using a 1.5 T whole-body imager (General Electric) and we evaluated their variation across hepatic segments and their association with age and sex. MATERIALS AND METHODS: One-hundred healthy volunteers aged 20-70 years (50% females) underwent MRI. Modified Look-Locker inversion recovery and multi-echo fast-spin-echo sequences were used to measure hepatic native global and segmental T1 and T2 values, respectively. RESULTS: T1 and T2 values exhibited good intra- and inter-observer reproducibility (coefficient of variation < 5%). T1 value over segment 4 was significantly lower than the T1 values over segments 2 and 3 (p < 0.0001). No significant regional T2 variability was detected. Segmental and global T1 values were not associated with age or sex. Global T2 values were independent from age but were significantly lower in males than in females. The lower and upper limits of normal for global T1 values were, respectively, 442 ms and 705 ms. The normal range for global T2 values was 35 ms-54 ms in males and 39 ms-54 ms in females. DISCUSSION: Liver T1 and T2 mapping is feasible and reproducible and the provided normal ranges may help to establish diagnosis and progression of various liver diseases.
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Fígado , Imageamento por Ressonância Magnética , Masculino , Feminino , Humanos , Valores de Referência , Voluntários Saudáveis , Reprodutibilidade dos Testes , Wortmanina , Valor Preditivo dos Testes , Fígado/diagnóstico por imagemRESUMO
Cardiac magnetic resonance represents the gold standard imaging technique to assess cardiac volumes, wall thickness, mass, and systolic function but also to provide noninvasive myocardial tissue characterization across almost all cardiac diseases. In patients with cardiac amyloidosis, increased wall thickness of all heart chambers, a mildly reduced ejection fraction and occasionally pleural and pericardial effusion are the characteristic morphologic anomalies. The typical pattern after contrast injection is represented by diffuse areas of late gadolinium enhancement, which can be focal and patchy in very early stages, circumferential, and subendocardial in intermediate stages or even diffuse transmural in more advanced stages.
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Amiloidose , Cardiomiopatias , Humanos , Amiloidose/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Volume Sistólico/fisiologiaRESUMO
Cardiac magnetic resonance (CMR) has become an essential tool for the evaluation of patients affected or at risk of developing cardiomyopathies (CMPs). In fact, CMR not only provides precise data on cardiac volumes, wall thickness, mass and systolic function but it also a non-invasive characterization of myocardial tissue, thus helping the early diagnosis and the precise phenotyping of the different CMPs, which is essential for early and individualized treatment of patients. Furthermore, several CMR characteristics, such as the presence of extensive LGE or abnormal mapping values, are emerging as prognostic markers, therefore helping to define patients' risk. Lastly new experimental CMR techniques are under investigation and might contribute to widen our knowledge in the field of CMPs. In this perspective, CMR appears an essential tool to be systematically applied in the diagnostic and prognostic work-up of CMPs in clinical practice. This review provides a deep overview of clinical applicability of standard and emerging CMR techniques in the management of CMPs.
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Cardiologia , Cardiomiopatias , Cardiopatias , Humanos , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Coração , Cardiopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Meios de Contraste , Imagem Cinética por Ressonância Magnética/métodosRESUMO
OBJECTIVES: The prognostic role of left ventricular (LV) papillary muscle abnormalities in patients with preserved LV systolic ejection fraction (LVEF) is unknown. We sought to evaluate the prognosis role of LV papillary muscle abnormalities by CMR in patients with ventricular arrhythmias, preserved LVEF with no cardiac disease. METHODS: A total of 391 patients with > 500/24 h premature ventricular complexes and/or with non-sustained ventricular tachycardia (NSVT), preserved LVEF, and no cardiac disease were enrolled. Different features of LV papillary muscles were considered: supernumerary muscles, papillary thickness, the attachment, late gadolinium enhancement (LGE). Dark-Paps was defined as end-systolic signal hypointensity of both papillary muscles in early post-contrast cine CMR images. Mitral valve prolapse, mitral annular disjunction (MAD), and myocardial LGE were considered. RESULTS: Dark-Paps was found in 79 (20%) patients and was more frequent in females. It was associated with higher prevalence of mitral valve prolapse and MAD. During a median follow-up of 2534 days, 22 hard cardiac events occurred. At Kaplan-Meier curve analysis, patients with Dark-Paps were at higher risk of events than those without (p < 0.0001). Dark-Paps was significantly associated with hard cardiac events in all the multivariate models. Dark-Paps improved prognostic estimation when added to NSVT (p = 0.0006), to LGE (p = 0.005) and to a model including NSVT+LGE (p = 0.014). Dark-Paps allowed a significant net reclassification when added to NSVT (NRI 0.30, p = 0.03), to LGE (NRI 0.25, p = 0.04), and to NSVT + LGE (NRI 0.32, p = 0.02). CONCLUSIONS: In LV papillary muscles, Dark-Paps is a novel prognostic marker in patients with ventricular arrhythmias and preserved ejection fraction. KEY POINTS: ⢠Papillary muscle abnormalities are seen in patients with ventricular arrhythmias and preserved left ventricular ejection fraction. ⢠Early post-contrast hypointensity of papillary muscles in end-systolic cine images (Dark-Paps) is a novel prognostic marker in patients with ventricular arrhythmias and preserved ejection fraction. ⢠Dark-Paps had an additive prognostic role over late gadolinium enhancement and non-sustained ventricular tachycardia.
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Cardiopatias , Prolapso da Valva Mitral , Taquicardia Ventricular , Feminino , Humanos , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/patologia , Meios de Contraste/farmacologia , Volume Sistólico , Prolapso da Valva Mitral/diagnóstico por imagem , Prognóstico , Função Ventricular Esquerda , Gadolínio/farmacologia , Imagem Cinética por Ressonância Magnética/métodos , Arritmias Cardíacas , Taquicardia Ventricular/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Valor Preditivo dos TestesRESUMO
The use of cocaine constitutes a major health problem. Cocaine use is associated with acute and chronic complications that might involve any system, the most common being the cardiovascular system. The precise incidence of cocaine-induced cardiomyopathy remains mysterious and probably underreported. Cocaine use should be considered in young patients presenting with chest pain or heart failure without other underlying risk factors. Cocaine-related cardiovascular complications can be acute or chronic and include ischemic and non-ischemic events. Frequent cocaine users have a seven-fold higher risk of myocardial infarction. In addition to its ischemic effects, other cardiovascular complications of cocaine use and abuse are hypertensive crises, aortic dissection or aortic rupture, cerebral hemorrhage, arrhythmias and sudden cardiac death, myocarditis, dilated cardiomyopathy, heart failure, and endocarditis. The mechanism of cocaine's cardiovascular toxicity relates to its sympathomimetic effect, to the block of voltage-dependent K+ and Na2+ channels, and a hypersensitivity reaction to drug or contaminants, such as amphetamine, sugars, or talc. Cardiac magnetic resonance (CMR) can provide a valuable assessment of cocaine-induced myocardial damage both in acute and chronic cardiac complications: it gives prognostic information in clinically relevant settings, and it identifies silent myocardial damage in asymptomatic patients. Indeed, CMR study should be considered in symptomatic cocaine users to assess the extent and evolution of myocardial injury. Furthermore, it was suggested to repeat CMR after 4-8 months of appropriate management to evaluate myocardial response to abstinence and medical therapy.
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Cocaína , Infarto do Miocárdio , Cocaína/efeitos adversos , Coração , Humanos , Espectroscopia de Ressonância Magnética , MiocárdioRESUMO
Heart failure with preserved ejection fraction (HFpEF) is characterized by an impaired ventricular filling resulting in the development of dyspnea and other HF symptoms. Even though echocardiography is the cornerstone to demonstrate structural and/or functional alterations of the heart as the underlying cause for the clinical presentation, cardiovascular magnetic resonance (CMR) represents the noninvasive gold standard to assess cardiac morphology, function, and tissue changes. Indeed, CMR allows quantification of biventricular volumes, mass, wall thickness, systolic function, and intra- and extracardiac flows; diastolic functional indices include transmitral and pulmonary venous velocities, left ventricular and left atrial filling velocities from volumetric changes, strain analysis from myocardial tagging, tissue phase contrast, and feature tracking. Moreover, CMR allows superior tissue characterization of the myocardium and the pericardium, which are crucial for a noninvasive etiological and histopathological assessment of HFpEF: conventional T1-weighted, T2-weighted, and post-contrast sequences are now complemented by quantitative mapping sequences, including T1 and T2 mapping as well as extracellular volume quantification. Further experimental sequences comprise diffusion tensor analysis, blood oxygenation-dependent sequences, hyperpolarized contrast agents, spectroscopy, and elastography. Finally, artificial intelligence is beginning to help clinicians deal with an increasing amount of information from CMR exams.
Assuntos
Insuficiência Cardíaca , Inteligência Artificial , Insuficiência Cardíaca/diagnóstico por imagem , Ventrículos do Coração , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular EsquerdaRESUMO
OBJECTIVES: Our aims were to obtain myocardial regional and global T2 values as a reference for normality for the first time using a GE scanner and to assess their association with physiological variables. METHODS: One hundred healthy volunteers aged 20-70 years (50% females) underwent cardiovascular magnetic resonance. Basal, mid-ventricular, and apical short-axis slices of the left ventricle were acquired by a multi-echo fast-spin-echo (MEFSE) sequence. Image analysis was performed with a commercially available software package. The T2 value was assessed in all 16 myocardial segments and the global value was the mean. RESULTS: The global T2 value averaged across all subjects was 52.2 ± 2.5 ms (range: 47.0-59.9 ms). Inter-study, intra-observer, and inter-observer reproducibility was good (coefficient of variation < 5%). 3.6% of the segments was excluded because of artifacts and/or partial-volume effects. Segmental T2 values differed significantly (p < 0.0001), with the lowest value in the basal anterolateral segment (50.0 ± 3.5 ms) and the highest in the apical lateral segment (54.9 ± 5.1 ms). Mean T2 was significantly lower in the basal slice compared to both mid-ventricular and apical slices and in the mid-ventricular slice than in the apical slice. Aging was associated with increased segmental and global T2 values. Females showed higher T2 values than males. T2 values were not correlated to heart rate. A significant inverse correlation was detected between global T2 values and mean wall thickness. CONCLUSIONS: The optimized MEFSE sequence allows for robust and reproducible quantification of segmental T2 values. Gender- and age-specific segmental reference values must be defined for distinguishing healthy and diseased myocardium. KEY POINTS: ⢠In healthy subjects, T2 values differ among myocardial segments and are influenced by age and gender. ⢠Normal T2 values in the myocardium, usable as a benchmark by other GE sites, were established.
Assuntos
Envelhecimento Saudável , Feminino , Coração/diagnóstico por imagem , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Miocárdio/patologia , Valor Preditivo dos Testes , Reprodutibilidade dos TestesRESUMO
BACKGROUND: No data are available about normal ranges for native T1 in human myocardium using General Electric (GE) scanners. PURPOSE: To establish normal ranges for myocardial T1 values and evaluate regional variability and the influence of physiological factors. STUDY TYPE: Prospective. SUBJECTS: One hundred healthy volunteers with normal electrocardiogram, no cardiovascular/systemic diseases, or risk factors (age range: 20-70 years; 50 females). FIELD STRENGTH/SEQUENCE: 1.5 T/Steady-state free precession cine and a modified Look-Locker inversion recovery sequence in diastole (also in systole for 61 volunteers). ASSESSMENT: Image analysis was performed by operators with >10 years experience in cardiac MR using commercially available software. T1 values were calculated for 16 myocardial segments, and the global value was the mean. Segments were grouped according to circumferential region (anterior, septal, inferior, and lateral) and to level (basal, medial, apical). Twenty images were analyzed twice by the same operator and by a different operator to assess reproducibility. STATISTICAL TESTS: Independent-samples t-test or Mann-Whitney test; paired sample t-test or Wilcoxon signed-rank test; one-way repeated measures ANOVA or Friedman tests; Pearson's or Spearman's correlation. Reproducibility evaluated using coefficient of variability (CoV). RESULTS: Due to artifacts and/or partial-volume effects, 45/1600 (2.8%) segments were excluded. A good intra- and inter-operator reproducibility was detected (CoV < 5%). There were significant differences in segmental T1 values (P < 0.05). A significant circumferential variability was present (P < 0.05): the mean native T1 value over the lateral region was significantly lower than in the other three regions. An increasing gradient from basal to apical slices was detected (P < 0.05). Segmental and global T1 values were not associated with age (range P = 0.052-0.911) but were significantly lower in males than in females (global: 993 ± 32 vs. 1037 ± 27 ms; P < 0.05) and significantly correlated with heart rate (range R for segmental values = 0.247-0.920; P < 0.05). Almost all segmental T1 values were inversely correlated with wall thickness (R from -0.233 to -0.514; P < 0.05). Systolic T1 values were significantly lower than diastolic values in basal anteroseptal segment, in all medial segments except the inferior one, and in all apical segments (P < 0.05). DATA CONCLUSION: Myocardial T1 values differ among myocardial regions, are influenced by sex, heart rate, and wall thickness and vary according to the cardiac cycle in healthy adults. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
Assuntos
Imagem Cinética por Ressonância Magnética , Miocárdio , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes , Sístole , Adulto JovemRESUMO
OBJECTIVES: Although cardiovascular magnetic resonance (CMR) is widely used in the assessment of left ventricular non-compaction (LVNC), there are no universally accepted diagnostic criteria and limited data regarding their prognostic value. We assessed the long-term prognostic role of the planimetric global Grothoff's criteria and of the CMR findings in predicting adverse cardiovascular events (CE). METHODS: We prospectively enrolled 78 patients (46.7 ± 18.7 years, 33.3% females) with documented positive Jenni's echocardiographic criteria for LVNC. Cine images were used to quantify function parameters and to assess for the presence of all four quantitative Grothoff's criteria (global Grothoff's criteria). Late gadolinium enhancement (LGE) images were acquired to detect the presence of replacement myocardial fibrosis. RESULTS: Petersen's CMR criterion for LVNC (NC/C ratio > 2.3 in at least one myocardial segment) was fulfilled in the whole population. Twenty-six patients fulfilled the global Grothoff's criteria (four out of four). The mean duration of the follow-up was 44.2 ± 27.4 months and 28 CE were registered: 10 ventricular tachycardias, 12 episodes of heart failure (HF), four strokes, and two cardiac deaths. In the multivariate analysis, the independent predictive factors for CE were positive global Grothoff's criteria (hazard ratio, HR = 3.33, 95% CI = 1.52-7.29; p = 0.003) and myocardial fibrosis (HR = 2.41, 95% CI = 1.08-5.36; p = 0.032). CONCLUSIONS: Positive global Grothoff's criteria and myocardial fibrosis were powerful predictors of CE in patients with a diagnosis of LVNC by CMR Petersen's criterion. Thus, we strongly suggest a step approach confirming the diagnosis of LVNC by using the global planimetric Grothoff's criteria, which showed a prognostic impact. KEY POINTS: ⢠Positive global Grothoff's criteria and replacement myocardial fibrosis were powerful predictors of cardiovascular events in patients with a diagnosis of LVNC by CMR Petersen's criterion. ⢠Positive global Grothoff's criteria were associated with a higher frequency of ventricular arrhythmias in patients with a diagnosis of LVNC by CMR Petersen's criterion.
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Meios de Contraste , Miocárdio Ventricular não Compactado Isolado , Feminino , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Miocárdio , Valor Preditivo dos Testes , Prognóstico , Função Ventricular EsquerdaRESUMO
AIMS: The aim of this registry was to evaluate the additional prognostic value of a composite cardiac magnetic resonance (CMR)-based risk score over standard-of-care (SOC) evaluation in a large cohort of consecutive unselected non-ischaemic cardiomyopathy (NICM) patients. METHODS AND RESULTS: In the DERIVATE registry (www.clinicaltrials.gov/registration: RCT#NCT03352648), 1000 (derivation cohort) and 508 (validation cohort) NICM patients with chronic heart failure (HF) and left ventricular ejection fraction <50% were included. All-cause mortality and major adverse arrhythmic cardiac events (MAACE) were the primary and secondary endpoints, respectively. During a median follow-up of 959 days, all-cause mortality and MAACE occurred in 72 (7%) and 93 (9%) patients, respectively. Age and >3 segments with midwall fibrosis on late gadolinium enhancement (LGE) were the only independent predictors of all-cause mortality (HR: 1.036, 95% CI: 1.0117-1.056, P < 0.001 and HR: 2.077, 95% CI: 1.211-3.562, P = 0.008, respectively). For MAACE, the independent predictors were male gender, left ventricular end-diastolic volume index by CMR (CMR-LVEDVi), and >3 segments with midwall fibrosis on LGE (HR: 2.131, 95% CI: 1.231-3.690, P = 0.007; HR: 3.161, 95% CI: 1.750-5.709, P < 0.001; and HR: 1.693, 95% CI: 1.084-2.644, P = 0.021, respectively). A composite clinical and CMR-based risk score provided a net reclassification improvement of 63.7% (P < 0.001) for MAACE occurrence when added to the model based on SOC evaluation. These findings were confirmed in the validation cohort. CONCLUSION: In a large multicentre, multivendor cohort registry reflecting daily clinical practice in NICM work-up, a composite clinical and CMR-based risk score provides incremental prognostic value beyond SOC evaluation, which may have impact on the indication of implantable cardioverter-defibrillator implantation.
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Cardiomiopatia Dilatada , Desfibriladores Implantáveis , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/terapia , Meios de Contraste , Feminino , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Volume Sistólico , Função Ventricular EsquerdaRESUMO
PURPOSE OF THE REVIEW: The aim of this review was to discuss the role of cardiac magnetic resonance (CMR) for the prognostic stratification of cardiomyopathies, highlighting strengths and limitations. RECENT FINDINGS: CMR is considered as a diagnostic pillar in the management of non-ischemic cardiomyopathies. Over the last years, attention has shifted from CMR's diagnostic capability towards prognostication in the various settings of cardiomyopathies. CMR is considered the gold standard imaging technique for the evaluation of ventricular volumes and systolic function as well as providing non-invasive virtual-histology by means of specific myocardial tissue characterization pulse sequences. CMR is an additive tool to risk stratifying patients and to identify those that require strict monitoring and more aggressive treatment.
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Cardiomiopatias , Coração , Humanos , Imageamento por Ressonância Magnética , Miocárdio , PrognósticoRESUMO
PURPOSE: To define reference values of cardiac volumes, dimensions, and new morpho-functional parameters normalized for age, gender, and body surface area by cine-bSSFP (balanced steady-state free-precession) magnetic resonance (MR). MATERIALS AND METHODS: We enrolled 308 healthy subjects subdivided by gender and by six age classes: class I, >15-20 years; class II, >20-30 years; class III, >30-40 years; class IV, >40-50 years; class V, >50-60 years; and class VI >60 years. Dimensional, volumetric and morpho-functional parameters of the left (LV) and right (RV) ventricles were measured using cine-bSSFP MRI at 1.5T. RESULTS: The LV and RV end-diastolic volume indexes (EDVi) were inversely related to age (P < 0.0001 r = -0.34 and P < 0.0001 r = -0.37, respectively). In addition, the LV mass index decreased with age (P = 0.0004, r = -0.21). The LV longitudinal shortening was not significantly different among groups: ≥15% in all populations (95% confidence interval [CI]: 16-31). The sphericity index measured in end-diastole was higher in females than in males (P < 0.03): the upper limit was 40% for males and 42% for females. The normality cutoff of LV global function index was ≥33% in males and ≥35% in females. The end-diastolic volume (EDV) of RV and LV was balanced (RV/LV ratio 0.85-1.15) without differences in the population. The LV EDV/mass was 1.0-1.8 in males and 1.0-2.1 in females. CONCLUSION: This study provides potential age- and gender-specific reference. LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017;45:1055-1067.
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Volume Cardíaco/fisiologia , Coração/diagnóstico por imagem , Coração/fisiologia , Imagem Cinética por Ressonância Magnética/métodos , Adolescente , Adulto , Fatores Etários , Feminino , Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Adulto JovemRESUMO
Myocardial remodelling involves not only the myocytes, but also non-myocyte cells and the extracellular matrix, which constitutes around 6 % of the normal heart and includes fluid, collagen and glycoproteins. In non-ischaemic dilated cardiomyopathy (DCM), the cardiac interstitium increases as a result of diffuse interstitial (microscopic) fibrosis, post-necrotic replacement (macroscopic) fibrosis or myocardial oedema. The activation of the renin-angiotensin-aldosterone system is a major determinant of fibroblasts activation and collagen deposition, with the transforming growth factor ß as the downstream signal mediator. Endomyocardial biopsy still represents the current reference method for interstitial and replacement myocardial fibrosis assessment, but cardiovascular magnetic resonance (CMR) allows in vivo detection of macroscopic fibrosis with post-contrast late enhancement imaging. Moreover, recent pre- and post-contrast T1 mapping techniques provide a quantitative estimation of myocardial interstitial remodelling, with potential diagnostic and prognostic clinical utility. Here, we review the pathophysiological mechanisms of myocardial interstitial remodelling in DCM, its non-invasive characterization with biomarkers and with CMR, as well as the most recent studies about their clinical utility.
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Biomarcadores/análise , Cardiomiopatia Dilatada/fisiopatologia , Matriz Extracelular/patologia , Espectroscopia de Ressonância Magnética/métodos , Miocárdio/patologia , Biópsia , Meios de Contraste , Fibrose/fisiopatologia , HumanosRESUMO
PURPOSE: This study was conducted to assess the role of atrial function by cardiac magnetic resonance (CMR) for the evaluation of diastolic physiology in patients with hypertrophic cardiomyopathy (HCM) compared to healthy controls. MATERIALS AND METHODS: We enrolled 23 consecutive patients affected by HCM and 43 healthy subjects as age-matched control cases (CC). CMR was performed through acquisition of cine steady-state free precession sequences using a 1.5-T scanner. Image postprocessing was carried out using Tracking Tool software. RESULTS: Atrial volumes were significantly higher in patients with HCM compared to CC: maximum atrial volume (p = 0.007) and minimum atrial volume (p = 0.01). A statistically significant difference was also observed in atrial ejection fraction in patients with HCM (p < 0.0001). The atrial volume curves defined as cavity volume over time (dV/t) showed significant differences: early atrial peak emptying rate (PERE) (maximum rate of emptying independent of atrial contraction) in HCM was -146 ± 53 ml/s versus -227 ± 86 ml/s in CC (p < 0.0001); active atrial peak emptying rate (PERA) (maximum rate of emptying secondary to atrial contraction) in HCM was -256 ± 80 ml/s versus -216 ± 104 ml/s in CC (p = 0.05); the atrial PER E/A ratio in HCM was 0.6 ± 0.2 versus 1.05 ± 0.5 in CC (p < 0.0001). CONCLUSIONS: This study demonstrated that in HCM patients with early diastolic dysfunction the parameters of left atrial function assessed by CMR are impaired before the ventricular diastolic indexes such as the early peak filling rate and the active peak filling rate.
Assuntos
Cardiomiopatia Hipertrófica/fisiopatologia , Diástole/fisiologia , Átrios do Coração/fisiopatologia , Imagem Cinética por Ressonância Magnética , Adulto , Estudos de Casos e Controles , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Compostos OrganometálicosRESUMO
PURPOSE: In steady state free precession (SSFP) images acquired with a repetition time/echo time (TR/TE) ≈ 2, fat is surrounded by a black boundary, called "India Ink" artifact. Indian Ink artifact may improve detection of intramyocardial fat. Aims of this study were: (i) to assess the accuracy of SSFP technique for the detection of fat metaplasia in remote myocardial infarction (RMI); (ii) to evaluate the inter- and intraobserver reproducibility for the quantification of intramyocardial fat using SSFP and fast spin echo/short TI inversion recovery (FSE/STIR) techniques. MATERIALS AND METHODS: A total of 200 patients (age 64 ± 10 years) with RMI (>1000 days) underwent MRI using a 1.5 Tesla (T) scanner. SSFP images (with a TR/TE ≈2), FSE and STIR images were acquired in short and long axis views. Fat was detected in FSE/STIR and SSFP images and its extent manually measured . The inter- and intraobserver agreement for the quantification of fat metaplasia using both the SSFP image and the FSE images was evaluated. RESULTS: Left ventricle intramyocardial fat was detected in SSFP images of 95 patients (47.5%) and in FSE/STIR images of 84 patients (42%). A very good agreement was found using the SSFP technique between investigators. CONCLUSION: SSFP sequence with TR/TE=2 is a valuable technique for identifying and quantifying the presence of fat tissue within the left ventricle myocardium in RMI.
Assuntos
Tecido Adiposo/patologia , Artefatos , Carbono , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por ComputadorRESUMO
Background: Ablation failures are common in case of intramural location of the arrhythmogenic substrate. Case summary: We report the case of a patient with cardiomyopathy contributed by frequent monomorphic ventricular arrhythmias (VAs) from intramural basal interventricular septum treated with double-balloon venous ethanol ablation (VEA) after a previous failed endocardial radiofrequency (RF) ablation. Discussion: Double-balloon VEA represents a safe and effective therapeutic option in case of intramural VAs also in the absence of venous collaterals joining selectively an intramural arrhythmic substrate.
RESUMO
In hypertrophic cardiomyopathy (HCM), late gadolinium enhancement (LGE) extent ≥15% of left ventricular mass is considered a prognostic risk factor. LGE extent increases over time and the clinical role of the progression of LGE over time (LGE rate) was not prospectively evaluated. We sought to evaluate the prognostic role of the LGE rate in HCM. We enrolled 105 patients with HCM who underwent cardiac magnetic resonance (CMR) at baseline (CMR-I) and after ≥2 years of follow-up (CMR-II). LGE rate was defined as the ratio between the increase of LGE extent (grams) and the time interval (months) between examinations. A combined end point of sudden cardiac death, resuscitated cardiac arrest, appropriate Implanted Cardioverter Defibrillator (ICD) intervention, and sustained ventricular tachycardia was used (hard events). The percentage of patients with LGE extent ≥15% increased from 9% to 20% from CMR-I to CMR-II (p = 0.03). During a median follow-up of 52 months, 25 hard events were recorded. The presence of LGE ≥15% at CMR-II allowed a significant reclassification of the risk of patients than at LGE ≥15% at CMR-I (net reclassification improvement 0.21, p = 0.046). On the MaxStat analysis, the optimal prognostic cut point for LGE rate was >0.07 g/month. On the Kaplan-Meier curve, patients with LGE rate >0.07 had worse prognosis than those without (p <0.0001). LGE rate >0.07 allowed a significant reclassification of the risk compared with LGE ≥15% at CMR-I and at CMR-II (net reclassification improvement 0.49, p = 0.003). In the multivariable models, LGE rate >0.07 was the best independent predictor of hard events. In conclusion, CMR should be repeated after 2 years to reclassify the risk for sudden death of those patients. A high LGE rate may be considered a novel prognostic factor in HCM.
Assuntos
Cardiomiopatia Hipertrófica , Meios de Contraste , Humanos , Prognóstico , Meios de Contraste/farmacologia , Gadolínio/farmacologia , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/patologia , Coração , Fatores de Risco , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos TestesRESUMO
BACKGROUND: Assessing myocardial strain by cardiac magnetic resonance feature tracking (FT) has been found to be useful in patients with overt hypertrophic cardiomyopathy (HCM). Little is known, however, of its role in sarcomere gene mutation carriers without overt left ventricular hypertrophy (subclinical HCM). METHODS: Thirty-eight subclinical HCM subjects and 42 healthy volunteers were enrolled in this multicenter case-control study. They underwent a comprehensive cardiac magnetic resonance study. Two-dimensional global radial, circumferential, and longitudinal strain of the left ventricle (LV) were evaluated by FT analysis. RESULTS: The subclinical HCM sample was 41 (22-51) years old and 32% were men. FT analysis revealed a reduction in global radial strain (29±7.2 versus 47.9±7.4; P<0.0001), global circumferential strain (-17.3±2.6 -versus -20.8±7.4; P<0.0001) and global longitudinal strain (-16.9±2.4 versus -20.5±2.6; P<0.0001) in subclinical HCM compared with control subjects. The significant differences persisted when considering the 23 individuals free of all the structural and functional ECG and cardiac magnetic resonance abnormalities previously described. Receiver operating characteristic curve analyses showed that the differential diagnostic performances of FT in discriminating subclinical HCM from normal subjects were good to excellent (global radial strain with optimal cut-off value of 40.43%: AUC, 0.946 [95% CI, 0.93-1.00]; sensitivity 90.48%, specificity 94.44%; global circumferential strain with cut-off, -18.54%: AUC, 0.849 [95% CI, 0.76-0.94]; sensitivity, 88.10%; specificity, 72.22%; global longitudinal strain with cut-off, -19.06%: AUC, 0.843 [95% CI, 0.76-0.93]; sensitivity, 78.57%; specificity, 78.95%). Similar values were found for discriminating those subclinical HCM subjects without other phenotypic abnormalities from healthy volunteers (global radial strain with optimal cut-off 40.43%: AUC, 0.966 [95% CI, 0.92-1.00]; sensitivity, 90.48%; specificity, 95.45%; global circumferential strain with cut-off, -18.44%: AUC, 0.866 [95% CI, 0.76-0.96]; sensitivity, 92.86%; specificity, 77.27%; global longitudinal strain with cut-off, -17.32%: AUC, 0.838 [95% CI, 0.73-0.94]; sensitivity, 90.48%; specificity, 65.22%). CONCLUSIONS: Cardiac magnetic resonance FT-derived parameters are consistently lower in subclinical patients with HCM, and they could emerge as a good tool for discovering the disease during a preclinical phase.
Assuntos
Cardiomiopatia Hipertrófica , Sarcômeros , Masculino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Feminino , Estudos de Casos e Controles , Sarcômeros/genética , Sarcômeros/patologia , Imagem Cinética por Ressonância Magnética/métodos , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , Espectroscopia de Ressonância Magnética , MutaçãoRESUMO
PURPOSE: The difference between rest and peak stress end-systolic pressure-volume relation (ΔESPVR) is an afterload-independent index of left ventricular (LV) contractility. We assessed the independent prognostic value of ΔESPVR index by dipyridamole stress-cardiovascular magnetic resonance (CMR) in patients with known/suspected coronary artery disease (CAD). METHODS: We considered 196 consecutive patients (62.74 ± 10.66 years, 49 females). Wall motion and perfusion abnormalities at rest and peak stress were analysed. Replacement myocardial fibrosis was detected by late gadolinium enhancement (LGE) technique. The ESPVR was evaluated at rest and peak stress from raw measurement of systolic arterial pressure and end-systolic volume by biplane Simpson's method. RESULTS: A reduced ΔESPVR index (≤ 0.02 mmHg/mL/m2) was found in 88 (44.9%) patients and it was associated with a lower LV ejection fraction (EF) and with a higher frequency of abnormal stress CMR and myocardial fibrosis. During a mean follow-up of 53.17 ± 28.21 months, 50 (25.5%) cardiac events were recorded: 5 cardiac deaths, 17 revascularizations, one myocardial infarction, 23 hospitalisations for heart failure or unstable angina, and 4 ventricular arrhythmias. According to Cox regression analysis, diabetes, family history, LVEF, abnormal stress CMR, myocardial fibrosis, and reduced ΔESPVR were significant univariate prognosticators. In the multivariate analysis the independent predictors were ΔESPVR index ≤ 0.02 mmHg/mL/m2 (hazard ratio-HR = 2.58, P = 0.007), myocardial fibrosis (HR = 2.13, P = 0.036), and diabetes (HR = 2.33, P = 0.012). CONCLUSION: ΔESPVR index by stress-CMR was independently associated with cardiac outcomes in patients with known/suspected CAD, in addition to replacement myocardial fibrosis and diabetes. Thus, the assessment of ΔESPVR index may be included into the standard stress-CMR exam to further stratify the patients.