Severity of aortic coarctation (CoA) is currently assessed by estimating trans-coarctation pressure drops through cardiac catheterization or echocardiography. In principle, more detailed information ...could be obtained non-invasively based on space- and time-resolved magnetic resonance imaging (4D flow) data. Yet the limitations of this imaging technique require testing the accuracy of 4D flow-derived hemodynamic quantities against other methodologies.
With the objective of assessing the feasibility and accuracy of this non-invasive method to support the clinical diagnosis of CoA, we developed an algorithm (4DF-FEPPE) to obtain relative pressure distributions from 4D flow data by solving the Poisson pressure equation. 4DF-FEPPE was tested against results from a patient-specific fluid-structure interaction (FSI) simulation, whose patient-specific boundary conditions were prescribed based on 4D flow data. Since numerical simulations provide noise-free pressure fields on fine spatial and temporal scales, our analysis allowed to assess the uncertainties related to 4D flow noise and limited resolution.
4DF-FEPPE and FSI results were compared on a series of cross-sections along the aorta. Bland-Altman analysis revealed very good agreement between the two methodologies in terms of instantaneous data at peak systole, end-diastole and time-averaged values: biases (means of differences) were +0.4 mmHg, −1.1 mmHg and +0.6 mmHg, respectively. Limits of agreement (2 SD) were ±0.978 mmHg, ±1.06 mmHg and ±1.97 mmHg, respectively. Peak-to-peak and maximum trans-coarctation pressure drops obtained with 4DF-FEPPE differed from FSI results by 0.75 mmHg and −1.34 mmHg respectively. The present study considers important validation aspects of non-invasive pressure difference estimation based on 4D flow MRI, showing the potential of this technology to be more broadly applied to the clinical practice.
Aims
The aim of the present study was to evaluate the prevalence and extent of myocardial fibrosis in patients with isolated left ventricular non‐compaction (LVNC) and to determine its relation to ...clinical status and LV systolic function.
Methods and results
The cardiac magnetic resonance imaging (MRI) database of our institution was searched for all patients with a first diagnosis of isolated LVNC. The diagnosis of isolated LVNC was based on the presence of standard cardiac MRI and clinical criteria. For each patient, cine and contrast‐enhanced cardiac MR images were analysed to evaluate LV systolic function and the prevalence and extent of late gadolinium enhancement (LGE), a surrogate of myocardial fibrosis. A total of 42 patients (mean age 46 ± 20 years, 62% male) were identified. Late gadolinium enhancement was observed in 23 (55%) patients with isolated LVNC, occupying 4.8 ± 6.7% of the LV mass. Both the presence and extent of LGE were significantly related to the number of abnormal clinical features (i.e. symptomatic status, resting electrocardiogram abnormalities, and 24 h Holter monitoring abnormalities; P< 0.001 and P= 0.001, respectively). Similarly, LGE was more prevalent and extensive in patients with LV ejection fraction (EF) <50% compared with patients with LVEF ≥50% (90 vs. 23%; P< 0.001 and 8.9 ± 7.6 vs. 1.1 ± 2.4%; P< 0.001, respectively). At multivariate analysis, both the presence and extent of LV LGE were independently related to LVEF (β = −0.63; P< 0.001 and β = −0.62; P< 0.001, respectively).
Conclusion
Myocardial fibrosis is related to clinical disease severity and LV systolic dysfunction in isolated LVNC.
The cohort of long-term survivors of heart transplant is expanding, and the assessment of these patients requires specific knowledge of the surgical techniques employed to implant the donor heart, ...the physiology of the transplanted heart, complications of invasive tests routinely performed to detect graft rejection (GR), and the specific pathologies that may affect the transplanted heart. A joint EACVI/Brazilian cardiovascular imaging writing group committee has prepared these recommendations to provide a practical guide to echocardiographers involved in the follow-up of heart transplant patients and a framework for standardized and efficient use of cardiovascular imaging after heart transplant. Since the transplanted heart is smaller than the recipient's dilated heart, the former is usually located more medially in the mediastinum and tends to be rotated clockwise. Therefore, standard views with conventional two-dimensional (2D) echocardiography are often difficult to obtain generating a large variability from patient to patient. Therefore, in echocardiography laboratories equipped with three-dimensional echocardiography (3DE) scanners and specific expertise with the technique, 3DE may be a suitable alternative to conventional 2D echocardiography to assess the size and the function of cardiac chambers. 3DE measurement of left (LV) and right ventricular (RV) size and function are more accurate and reproducible than conventional 2D calculations. However, clinicians should be aware that cardiac chamber volumes obtained with 3DE cannot be compared with those obtained with 2D echocardiography. To assess cardiac chamber morphology and function during follow-up studies, it is recommended to obtain a comprehensive echocardiographic study at 6 months from the cardiac transplantation as a baseline and make a careful quantitation of cardiac chamber size, RV systolic function, both systolic and diastolic parameters of LV function, and pulmonary artery pressure. Subsequent echocardiographic studies should be interpreted in comparison with the data obtained from the 6-month study. An echocardiographic study, which shows no change from the baseline study, has a high negative predictive value for GR. There is no single systolic or diastolic parameter that can be reliably used to diagnose GR. However, in case several parameters are abnormal, the likelihood of GR increases. When an abnormality is detected, careful revision of images of the present and baseline study (side-by-side) is highly recommended. Global longitudinal strain (GLS) is a suitable parameter to diagnose subclinical allograft dysfunction, regardless of aetiology, by comparing the changes occurring during serial evaluations. Evaluation of GLS could be used in association with endomyocardial biopsy (EMB) to characterize and monitor an acute GR or global dysfunction episode. RV size and function at baseline should be assessed using several parameters, which do not exclusively evaluate longitudinal function. At follow-up echocardiogram, all these parameters should be compared with the baseline values. 3DE may provide a more accurate and comprehensive assessment of RV size and function. Moreover, due to the unpredictable shape of the atria in transplanted patients, atrial volume should be measured using the discs' summation algorithm (biplane algorithm for the left atrium) or 3DE. Tricuspid regurgitation should be looked for and properly assessed in all echocardiographic studies. In case of significant changes in severity of tricuspid regurgitation during follow-up, a 2D/3D and colour Doppler assessment of its severity and mechanisms should be performed. Aortic and mitral valves should be evaluated according to current recommendations. Pericardial effusion should be serially evaluated regarding extent, location, and haemodynamic impact. In case of newly detected pericardial effusion, GR should be considered taking into account the overall echocardiographic assessment and patient evaluation. Dobutamine stress echocardiography might be a suitable alternative to routine coronary angiography to assess cardiac allograft vasculopathy (CAV) at centres with adequate experience with the methodology. Coronary flow reserve and/or contrast infusion to assess myocardial perfusion might be combined with stress echocardiography to improve the accuracy of the test. In addition to its role in monitoring cardiac chamber function and in diagnosis the occurrence of GR and/or CAV, in experienced centres, echocardiography might be an alternative to fluoroscopy to guide EMB, particularly in children and young women, since echocardiography avoids repeated X-ray exposure, permits visualization of soft tissues and safer performance of biopsies of different RV regions. Finally, in addition to the indications about when and how to use echocardiography, the document also addresses the role of the other cardiovascular imaging modalities during follow-up of heart transplant patients. In patients with inadequate acoustic window and contraindication to contrast agents, pharmacological SPECT is an alternative imaging modality to detect CAV in heart transplant patients. However, in centres with adequate expertise, intravascular ultrasound (IVUS) in conjunction with coronary angiography with a baseline study at 4-6 weeks and at 1 year after heart transplant should be performed to exclude donor coronary artery disease, to detect rapidly progressive CAV, and to provide prognostic information. Despite the fact that coronary angiography is the current gold-standard method for the detection of CAV, the use of IVUS should also be considered when there is a discrepancy between non-invasive imaging tests and coronary angiography concerning the presence of CAV. In experienced centres, computerized tomography coronary angiography is a good alternative to coronary angiography to detect CAV. In patients with a persistently high heart rate, scanners that provide high temporal resolution, such as dual-source systems, provide better image quality. Finally, in patients with insufficient acoustic window, cardiac magnetic resonance is an alternative to echocardiography to assess cardiac chamber volumes and function and to exclude acute GR and CAV in a surveillance protocol.
Abstract Cardiovascular magnetic resonance (CMR) has evolved from a pioneering research tool to an established noninvasive imaging method for detecting inducible myocardial perfusion deficits. In ...this consensus document, experts of different imaging techniques summarize the existing body of evidence regarding CMR perfusion as a viable complement to other established noninvasive tools for the assessment of perfusion and discuss the advantages and pitfalls of the technique. A rapid, standardized CMR perfusion protocol is described, which is safe, clinically feasible, and cost-effective for centers with contemporary magnetic resonance equipment. CMR perfusion can be recommended as a routine diagnostic tool to identify inducible myocardial ischemia.
Several studies using echocardiography identified epicardial adipose tissue (EPI) as an important cardiometabolic risk marker. However, validation compared with magnetic resonance imaging (MRI) or ...computed tomography has not been performed. Moreover, pericardial adipose tissue (PERI) has recently been shown to have some correlation with cardiovascular disease risk factors. The aims of this study were to validate echocardiographic analyses compared with MRI and to evaluate which cardiac fat depot (EPI or PERI) is the most appropriate cardiovascular risk marker.
Forty-nine healthy subjects were studied (age range, 25-68 years; body mass index, 21-40 kg/m(2)), and PERI and EPI fat depots were measured using echocardiography and MRI. Findings were correlated with MRI visceral fat and subcutaneous fat, blood pressure, insulin sensitivity, triglycerides, cholesterol, insulin, glucose, and 10-year coronary heart disease risk.
Most cardiac fat was constituted by PERI (about 77%). PERI thickness by echocardiography was well correlated with MRI area (r = 0.36, P = .009), and independently of the technique used for quantification, PERI was correlated with body mass index, waist circumference, visceral fat, subcutaneous fat, blood pressure, insulin sensitivity, triglycerides, cholesterol, glucose, and coronary heart disease risk. On the contrary, EPI thicknesses correlated only with age did not correlate significantly with MRI EPI areas, which were found to correlate with age, body mass index, subcutaneous fat, and hip and waist circumferences.
Increased cardiac fat in the pericardial area is strongly associated with features of the metabolic syndrome, whereas no correlation was found with EPI, indicating that in clinical practice, PERI is a better cardiometabolic risk marker than EPI.
The EuroCMR registry sought to evaluate indications, image quality, safety and impact on patient management of clinical routine CMR in a multi-national European setting. Furthermore, interim analysis ...of the specific protocols should underscore the prognostic potential of CMR.
Multi-center registry with consecutive enrolment of patients in 57 centers in 15 countries. More than 27000 consecutive patients were enrolled.
The most important indications were risk stratification in suspected CAD/Ischemia (34.2%), workup of myocarditis/cardiomyopathies (32.2%), as well as assessment of viability (14.6%). Image quality was diagnostic in more than 98% of cases. Severe complications occurred in 0.026%, always associated with stress testing. No patient died during or due to CMR. In 61.8% CMR findings impacted on patient management. Importantly, in nearly 8.7% the final diagnosis based on CMR was different to the diagnosis before CMR, leading to a complete change in management. Interim analysis of suspected CAD and risk stratification in HCM specific protocols revealed a low rate of adverse events for suspected CAD patients with normal stress CMR (1.0% per year), and for HCM patients without LGE (2.7% per year).
The most important indications in Europe are risk stratification in suspected CAD/Ischemia, work-up of myocarditis and cardiomyopathies, as well as assessment of viability. CMR imaging is a safe procedure, has diagnostic image quality in more than 98% of cases, and its results have strong impact on patient management. Interim analyses of the specific protocols underscore the prognostic value of clinical routine CMR in CAD and HCM.
Since the introduction of Magnetic Resonance Imaging (MRI) as a diagnostic technique, the number of people exposed to electromagnetic fields (EMF) has increased dramatically. In this review, based on ...the results of a pioneer study showing in vitro and in vivo genotoxic effects of MRI scans, we report an updated survey about the effects of non-ionizing EMF employed in MRI, relevant for patients' and workers' safety. While the whole data does not confirm a risk hypothesis, it suggests a need for further studies and prudent use in order to avoid unnecessary examinations, according to the precautionary principle.
The use of apical views focused on the left atrium (LA) has improved the accuracy of LA volume evaluation by two-dimensional (2D) echocardiography. However, routine cardiovascular magnetic resonance ...(CMR) evaluation of LA volumes still uses standard 2- and 4-chamber cine images focused on the left ventricle (LV). To investigate the potential of LA-focused CMR cine images, we compared LA maximuml (LAVmax) and minimum (LAVmin) volumes, and emptying fraction (LAEF), calculated on both standard and LA-focused long-axis cine images, with LA volumes and LAEF obtained by short-axis cine stacks covering the LA. LA strain was also calculated and compared between standard and LA-focused images.
LA volumes and LAEF were obtained from 108 consecutive patients by applying the biplane area-length algorithm to both standard and LA-focused 2- and 4-chamber cine images. Manual segmentation of a short-axis cine stack covering the LA was used as the reference method. In addition, LA strain reservoir (εs), conduit (εe) and booster pump (εa) were calculated using CMR feature-tracking.
Compared to the reference method, the standard approach significantly underestimated LA volumes (LAVmax: bias − 13 ml; LOA = + 11, − 37 ml; LAVmax i: bias − 7 ml/m2; LOA = + 7, − 21 ml/m2; LAVmin; bias − 10 ml, LOA: + 9, − 28 ml; LAVmin i: bias − 5 ml/m2, LOA: + 5, − 16 ml/m2), and overestimated LA-EF (bias 5%, LOA: + 23, − 14%). Conversely, LA volumes (LAVmax: bias 0 ml; LOA: + 10, − 10 ml; LAVmax i: bias 0 ml/m2; LOA: + 5, − 6 ml/m2; LAVmin: bias − 2 ml; LOA: + 7, − 10 ml; LAVmin i: bias − 1 ml/m2; LOA: + 3, − 5 ml/m2) and LAEF (bias 2%, LOA: + 11, − 7%) by LA-focused cine images were similar to those measured using the reference method. LA volumes by LA-focused images were obtained faster than using the reference method (1.2 vs 4.5 min, p < 0.001). LA strain (εs: bias 7%, LOA = 25, − 11%; εe: bias 4%, LOA = 15, − 8%; εa: bias 3%, LOA = 14, − 8%) was significantly higher in standard vs. LA-focused images (p < 0.001).
LA volumes and LAEF measured using dedicated LA-focused long-axis cine images are more accurate than using standard LV-focused cine images. Moreover, LA strain is significantly lower in LA-focused vs. standard images.
Anomalous aortic origin of the coronary artery (AAOCA) is a rare disease associated with sudden cardiac death, usually related to physical effort in young people. Clinical routine tests fail to ...assess the ischemic risk, calling for novel diagnostic approaches. To this aim, some recent studies propose to assess the coronary blood flow (CBF) in AAOCA by computational simulations but they are limited by the use of data from literature retrieved from normal subjects. To overcome this limitation and obtain a reliable assessment of CBF, we developed a fully patient-specific lumped parameter model based on clinical imaging and in-vivo data retrieved during invasive coronary functional assessment of subjects with AAOCA. In such a way, we can estimate the CBF replicating the two hemodynamic conditions in-vivo analyzed. The model can mimic the effective coronary behavior with high accuracy and could be a valuable tool to quantify CBF in AAOCA. It represents the first step required to move toward a future clinical application with the aim of improving patient care. The study was registered at Clinicaltrial.gov with (ID: NCT05159791, date 2021-12-16).
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