Cardiovascular Magnetic Resonance Imaging Study Research Articles

Safety of Continuing Trastuzumab for Mild Cardiotoxicity: A Cardiovascular Magnetic Resonance Imaging Study

The safety of continuing human epidermal growth factor receptor 2 (HER2)–targeted therapy in women with mild cardiotoxicity remains unclear. We performed a retrospective matched cohort study of 14 patients with human epidermal growth factor receptor 2–positive breast cancer receiving sequential anthracycline and trastuzumab therapy, nested within the Evaluation of Myocardial Changes During Breast Adenocarcinoma Therapy to Detect Cardiotoxicity Earlier With MRI (EMBRACE-MRI) trial. Among patients who developed cardiotoxicity and were treated with heart failure therapy, we compared those who had trastuzumab therapy interrupted to a matched cohort who continued trastuzumab therapy. By a median of 2.5 years of follow-up, no significant differences were present between the groups in the proportion with magnetic resonance imaging–measured left ventricular ejection fraction < 40%, magnetic resonance imaging–measured left ventricular volumes, left ventricular ejection fraction, edema, fibrotic markers, cardiopulmonary fitness, or quality of life.

Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population: a two-sample bidirectional Mendelian randomization study.

Left ventricular (LV) remodeling and diastolic function in people with heart failure (HF) are correlated with iron status; however, the causality is uncertain. This Mendelian randomization (MR) study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population. Transferrin saturation (TSAT), total iron binding capacity (TIBC), and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies. Individuals without myocardial infarction history, HF, or LV ejection fraction (LVEF) < 50% (n = 16,923) in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset. The dataset included LV end-diastolic volume, LV end-systolic volume, LV mass (LVM), and LVM-to-end-diastolic volume ratio (LVMVR). We used a two-sample bidirectional MR study with inverse variance weighting (IVW) as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results. In the IVW analysis, one standard deviation (SD) increased in TSAT significantly correlated with decreased LVMVR (β = -0.1365; 95% confidence interval [CI]: -0.2092 to -0.0638; P = 0.0002) after Bonferroni adjustment. Conversely, no significant relationships were observed between other iron and LV parameters. After Bonferroni correction, reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT (β = -0.0699; 95% CI: -0.1087 to -0.0311; P = 0.0004). No heterogeneity or pleiotropic effects evidence was observed in the analysis. We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population.

Kiosk 1R-TB-04 - Coronary Vascular and Structural Function in Females with History of Pre-eclampsia—an Oxygenation-sensitive Cardiovascular Magnetic Resonance Imaging Study

Kiosk 1R-TB-04 - Coronary Vascular and Structural Function in Females with History of Pre-eclampsia—an Oxygenation-sensitive Cardiovascular Magnetic Resonance Imaging Study

Coronary vascular function in females with history of hypertensive disorders of pregnancy an oxygenation-sensitive cardiovascular magnetic resonance imaging study

Abstract Background Hypertensive disorders of pregnancy (HDP), including gestational hypertension and preeclampsia, have been associated with increased risk for cardiovascular disease decades after HDP pregnancy. HDP is thought to unmask pre-existing cardiovascular risk in the mother; and in addition HDP triggers a cascade of inflammatory and oxidative stress which leads to vascular endothelial dysfunction and abnormalities in cardiac structure and function evident early post-partum that may persist sub-clinically. Oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR) is an emerging approach that can identify dynamic changes of myocardial oxygenation as a marker for coronary vascular function. The objective of this study was to assess coronary vascular function in females with history of HDP using OS-CMR. Methods We analyzed data from two short axis OS-CMR slices in 20 females with history of HDP, including gestational hypertension, preeclampsia and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) and 20 healthy controls with history of normal pregnancy acquired on a 1.5T MRI scanner. Images were analyzed using a prototype tissue oxygenation module. The images were normalized for signal intensity to both ventricular blood pools. We used both traditional statistics and feature selection machine learning algorithms to select for predictive biomarkers in the dataset. Finally, we used a random forest classifier model for disease classification. We report area under the receiver operating curve (AUROC) as a metric for diagnostic accuracy. Results Global breathing-induced myocardial oxygenation reserve (B-MORE) of the mid left ventricular slice was significantly reduced in HDP females (-1.6 ± 14.8) when compared to healthy controls (11.3 ± 17.2, p=0.03), when normalized to ventricular blood pools (Figure 1A). Our feature selection algorithm selected the signal intensity during end-systole normalized to the series as the most predictive biomarker. Our model, which integrated data from &amp;gt;3,300 discrete data points per participant, correctly differentiated healthy controls from women with HDP history with a 90% ± 3% AUROC accuracy, indicating high sensitivity and specificity (Figure 1B). Conclusion Compared to healthy controls, females with history of HDP have abnormal coronary vascular function, as shown by reduced myocardial oxygenation on OS-CMR. Combining advanced machine learning approaches can further enhance the potential application of OS-CMR to risk stratify females with adverse pregnancy outcomes susceptible to future cardiovascular disease.

Effect of concomitant atrial septal defect on left ventricular function in adult patients with unrepaired Ebstein's anomaly: a cardiovascular magnetic resonance imaging study

BackgroundDue to the heterogeneity of anatomic anomalies in Ebstein's anomaly (EA), particularly in the subset of patients with atrial septal defect (ASD), hemodynamic changes, which ultimately cause left ventricular (LV) deterioration remain unclear. The current study aimed to investigate the effect of concomitant ASD on LV function using cardiovascular magnetic resonance (CMR) imaging in patients with EA. MethodsThis study included 31 EA patients with ASD, 76 EA patients without ASD, 35 patients with simple ASD and 40 healthy controls. Left/right ventricular (RV, the RV was defined as a summation of the functional RV and atrialized RV in EA patients) volumes and functional parameters, LV strain parameters, and echocardiogram indices were compared among the four groups. Associations between variables were evaluated via Spearman or Pearson correlation analyses. The association between risk factors and LV ejection fraction (EF) was determined via multivariate linear regression analysis. ResultsBoth EA patients and ASD patients had a higher RV/LV end-diastolic volume (RVEDV/LVEDV) as well as lower LV and RV ejection fractions (LVEF/RVEF) compared to healthy controls (all p < 0.05). Moreover, the EA patients with ASD had a significantly higher RVEDV/LVEDV and a lower LVEF and RVEF than those without ASD (all p < 0.05). Multivariate linear regression analysis revealed that the presence of ASD was independently associated with LVEF (β = − 0.337, p < 0.001). The RVEDV/LVEDV index was associated with LVEF (r = − 0.361, p < 0.001). Furthermore, the LV longitudinal peak diastolic strain rate (PDSR) was lower in EA patients with ASD than those without ASD, patients with simple ASD, and healthy controls (p < 0.05). ConclusionConcomitant ASD is an important risk factor of LV dysfunction in patients with EA, and diastolic dysfunction is likely the predominate mechanism related to LV dysfunction.

Abstract 14967: Rate of Growth of the Right Ventricular Outflow Tract in Repaired Tetralogy of Fallot: A Cardiovascular Magnetic Resonance Imaging Study

Introduction: Patients with repaired tetralogy of Fallot (rTOF) often require pulmonary valve replacement (PVR). Transcatheter PVR is a less invasive alternative to surgery but many right ventricular outflow tracts (RVOTs) are too large. Understanding the rate of RVOT growth may help optimize timing of referral. This study examined the growth of the RVOT over time in rTOF. Methods: We retrospectively analyzed serial cardiac MRI (CMR) data from 121 patients with TOF (median 3 MRIs per patient; range 2 to 10) to calculate the rate of increase in perimeter-derived diameters of the proximal infundibulum, middle RVOT, and distal RVOT at the point of PA bifurcation (Figure 1). The median age at first CMR was 14.7 years (range 3.3, 43.6 years) with a mean interval between first and last CMR of 8 years ± 3 years. Results: All parameters increased over time. The proximal RVOT increased at a rate of 4.1 mm per 10 years (p &lt; 0.001); the mid and distal RVOT both increased at a rate of 3.1 mm per 10 years (p &lt; 0.001) (Figure 2). The RVOT was larger on average in patients with a higher RV end diastolic volume (RVEDV) at first MRI and in patients with a higher pulmonary regurgitation (PR) fraction at first MRI. Patients with greater increases in RV EDV (Spearman correlation 0.48, p &lt; 0.001) or PR fraction (Spearman correlation 0.27, p = 0.003) over time had greater RVOT growth. Conclusions: This largest-to-date serial CMR study of patients with rTOF detailed the rate of growth of the RVOT over time. More rapid growth was associated with higher PR fraction and larger RVEDV. This data may be useful in the design and clinical use of transcatheter pulmonary valves.

Left Atrial Dysfunction in Children with Repaired Pulmonary Artery Atresia with Ventricular Septal Defect: A Cardiovascular Magnetic Resonance Imaging Study.

(1) Background: The left atrium (LA) is much more than a reservoir for left ventricular filling. The aim of this study was to assess the LA volume and function in patients with repaired pulmonary artery atresia with ventricular septal defect (rPA/VSD) using CMR. (2) Methods: 31 pediatric patients with rPA/VSD and 30 healthy controls were prospectively recruited. Left atrial ejection fraction (EF), strain and strain rate of three phases (reservoir, conduit, and pump) and left atrial volume were measured with cardiac function analysis software. (3) Results: Patients with rPA/VSD had decreased maximal volume index (p = 0.008). Compared to controls, LA reservoir strain and strain rate, conduit strain and strain rate, booster pump strain rate, total EF and passive EF were significantly lower (p = 0.001, p < 0.001, p = 0.001, p = 0.02, p = 0.03, p < 0.001, p < 0.001); the patients with preserved but lower RVEF(<50%) had lower reservoir strain, reservoir strain rate and pump strain rate (p = 0.01, p = 0.02, p = 0.04, respectively) than the patients with higher RVEF (≥50%). (4) Conclusions: In patients with rPA/VSD, LA function was altered when biventricular EF was preserved, which may provide an early indication of left ventricular diastolic dysfunction. CMR can detect LA dysfunction at an early stage, even before LA enlargement.

The stiff male arterial system seems to establish itself well before puberty

Abstract Background Increased vascular stiffness in adults is associated with symptomatic cardiovascular disease independently of other risk factors. From puberty and onwards, men have higher aortic pulse-wave velocity than women explaining part of the male overrepresentation of early cardiovascular disease. It is not known if the stiff male arterial system is related to adult life-style or develops under the influence of male hormones, or if it is already present before puberty. According to the hyperbolic Bramwell-Hill relation, early changes must be expected to become detectable in aortic distensibility before influencing aortic pulse-wave velocity. Purpose The objective of this study was to quantitate sex-related differences in aortic distensibility and pulse-wave velocity in pre-pubertal children. Methods 150 children aged 8–9 years (75 girls and 75 boys) were recruited to a cardiovascular magnetic resonance imaging (CMR) study of the importance of in vitro fertilization (IVF) for aortic distensibility. Data did not show differences related to the mode of conception (natural vs. IVF), and pooled data are reported here. Conductance artery stiffness was determined from ascending, descending and abdominal aorta distensibility and from arch and abdominal aorta pulse-wave velocity (PWV). Data were analyzed blinded to child sex and mode of conception and related to left heart function as determined from flow and volumetric CMR data. The effects of sex on ascending aorta distensibility and total aortic PWV were examined in four linear regression models by stepwise adjustment for potential confounders. Results Systolic and diastolic blood pressures, cardiac output and total peripheral resistance did not differ between the sexes. Pulse pressure, however, was a mean of 2 mmHg lower and heart rate 7 bpm higher in girls (Table 1), and corresponding to the lower heart rate, left ventricle (LV) end-diastolic volume index and left ventricle stroke volume were 7 mL and 5 mL, respectively, higher in boys. LV peak-filling rate indexed to LV end-diastolic volume was 0.5 s-1 lower in boys, but in general LV filling and left atrium emptying parameters were equal. Distensibility of the ascending and descending aorta were both significantly higher in girls as compared to boys, whereas boys and girls had equal abdominal aortic distensibility and equal aortic pulse-wave velocities. Distensibility of the ascending aorta remained statistically significant after adjustment for potential confounders (Table 2). Conclusion Without yet significantly affecting pulse wave velocity or left ventricle function, pre-pubertal boys had significantly lower distensibility of the ascending aorta and the aortic arch than pre-pubertal girls. This is the part of the aorta primarily responsible for the aortic Windkessel function, and it seems that the stiffer arterial system seen in adult men as compared to adult women may already be present in childhood well before puberty. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Novo Nordisk Foundation Table 1Table 2

Impairment of left atrial function in pediatric patients with repaired tetralogy of Fallot: a cardiovascular magnetic resonance imaging study.

We aimed to assess left atrial (LA) strain before LA dilatation in patients with repaired tetralogy of Fallot (rTOF) compared with healthy controls. We also determined the effects of right atrial (RA) dilatation on LA performance using cardiovascular magnetic resonance-feature tracking (CMR-FT). Forty-nine pediatric patients with rTOF and 36 age- and sex-matched healthy controls were prospectively recruited between June 2017 and August 2019. Balanced steady-state free precession (2D b-SSFP) cine, 2D late gadolinium enhancement (LGE) and phase-contrast (PC) sequences were acquired on 1.5 and 3.0 Tesla scanners. Both ventricular and atrial volumes and ejection fraction were measured. Left ventricular (LV) strain and diastolic strain rates were evaluated between the rTOF patient and control groups. LA reservoir (Ɛs), conduit (Ɛe), and booster strain (Ɛa) were determined at LV end-systole, LV diastasis, and pre-LA systole, respectively. The first derivatives of the respective strains yielded corresponding peak strain rates. Statistical analysis was performed using the t-test and Mann-Whitney test for parametric and non-parametric variables, respectively. Correlations were assessed using Pearson's correlation coefficient for normally distributed variables and Spearman's correlation coefficient for non-parametric data. Intra-observer and inter-observer variabilities of LA strain and strain rate measurements were determined from ten randomly selected rTOF patients and ten control subjects. LA strain was significantly lower in patients with rTOF compared with controls (Ɛs, P < 0.001; Ɛe, P = 0.002; Ɛa, P < 0.001). The correlations between LA strain and RA stroke volume indices (SVi) and RA ejection fraction (EF) were moderate (Ɛs and SVi, r = 0.538, P < 0.001; Ɛs and RA EF, r = 0.493, P < 0.001; Ɛe and SVi, r = 0.532, P < 0.001; Ɛe and RA EF, r = 0.466, P < 0.001). LA strain and strain rates had good reproducibility in intra-observer and inter-observer analyses. LA strain and strain rates decreased in pediatric patients with rTOF compared with controls before LA enlargement. A dysfunction in LA performance might precede LV dysfunction in patients with rTOF, even in the early stages after repair.

Global longitudinal strain by feature-tracking cardiovascular magnetic resonance imagingpredicts mortality in patients with end-stage kidney disease.

BackgroundPatients with end-stage kidney disease (ESKD) are at increased risk of premature death, with cardiovascular disease being the predominant cause of death. We hypothesized that left ventricular global longitudinal strain (LV-GLS) measured by feature-tracking cardiovascular magnetic resonance imaging (CMRI) would be associated with all-cause mortality in patients with ESKD.MethodsA pooled analysis of CMRI studies in patients with ESKD acquired within a single centre between 2002 and 2016 was carried out. CMR parameters including LV ejection fraction (LVEF), LV mass index, left atrial emptying fraction (LAEF) and LV-GLS were measured. We tested independent associations of CMR parameters with survival using a multivariable Cox model.ResultsAmong 215 patients (mean age 54 years, 62% male), mortality was 53% over a median follow-up of 5 years. The median LVEF was 64.7% [interquartile range (IQR) 58.5–70.0] and the median LV-GLS was −15.3% (IQR −17.24 to −13.6). While 90% of patients had preserved LVEF (>50%), 58% of this group had abnormal LV-GLS (>−16%). On multivariable Cox regression, age {hazard ratio [HR] 1.04 [95% confidence interval (CI) 1.02–1.05]}, future renal transplant [HR 0.29 (95% CI 0.17–0.47)], LAEF [HR 0.98 (95% CI 0.96–1.00)] and LV-GLS [HR 1.08 (95% CI 1.01–1.16)] were independently associated with mortality.ConclusionsIn this cohort of patients with ESKD, LV-GLS on feature-tracking CMRI and LAEF was associated with all-cause mortality, independent of baseline clinical variables and future renal transplantation. This effect was present even when >90% of the cohort had normal LVEF. Using LV-GLS instead of LVEF to diagnose cardiac dysfunction in patients with ESKD could result in a major advance in our understanding of cardiovascular disease in ESKD.

The Impact of a Bicuspid Aortic Valve on Aortic Geometry and Function in Patients with Aortic Coarctation: A Comprehensive CMR Study

Background: An isolated bicuspid aortic valve (BAV) is associated with structural and functional abnormalities of the aorta and the left ventricle (LV). Although ~50% of patients with aortic coarctation (CoA) have a BAV, less is known about its impact on LV function and aortic geometry and function in CoA patients. In this cardiovascular magnetic resonance imaging (CMR) study, we analysed markers of LV and aortic function as well as aortic geometry in a large cohort of CoA patients with a BAV and compared them with CoA patients with a tricuspid aortic valve (TAV). Methods: We included 48 patients with a BAV (18.4 ± 9.3 years) and 45 patients with TAV (20.7 ± 9.9 years). LV volumes, mass and ejection fraction as well as aortic distensibilty, pulse wave velocity (PWV) were measured from standard cine CMR and phase-contrast CMR images. 2-dimensional CMR feature tracking (2DCMR-FT) was performed to measure longitudinal, circumferential and radial strain and strain rate of the LV. Aortic arch geometry was classified as romanic, gothic and crenel. Results: LV volumes, mass and ejection fraction as well as aortic distensibility and PWV did not significantly differ between the BAV and the TAV group. There was also no significant difference for LV global longitudinal, radial and circumferential strain and strain rate between both groups. Patients with a BAV had more commonly a gothic aortic arch compared to TAV patients, but this difference was not statistically significant (22 vs. 14, p = 0.2). Ascending and descending aortic distensibility correlated with LV mass in the entire patient group (p < 0.001). Global longitudinal, circumferential and radial strain (GLS, GCS, GRS) and global longitudinal and circumferential strain rate (GLSR, GCSR) correlated with LV ejection fraction (p < 0.001). Conclusion: Our data suggest that the presence of a BAV does not adversely impact LV and aortic function in children and young adults with CoA. The correlation of global circumferential, longitudinal and radial strain values with LV ejection fraction demonstrates that 2D-CMR-FT might provide additional information related to ventricular function in CoA patients.

Co-existing cerebrovascular atherosclerosis predicts subsequent vascular event: a multi-contrast cardiovascular magnetic resonance imaging study

BackgroundIt is still unknown that whether co-existing intracranial stenosis and extracranial carotid vulnerable plaques have higher predictive value for subsequent vascular events. This study aimed to determine the relationship between co-existing extracranial carotid vulnerable plaques and intracranial stenosis and subsequent vascular events utilizing cardiovascular magnetic resonance (CMR) vessel wall imaging.MethodsPatients who had recent cerebrovascular symptoms in anterior circulation (< 2 weeks) were consecutively enrolled and underwent multi-contrast CMR vessel wall imaging for extracranial carotid arteries and 3D time-of flight CMR angiography for intracranial arteries at baseline. After baseline examination, all patients were followed-up for at least 1 year to determined recurrence of vascular events. The co-existing cerebrovascular atherosclerosis was defined as presence of both intracranial artery stenosis and at least one the following measures of extracranial artery atherosclerosis: plaque, calcification, lipid-rich necrotic core (LRNC), or intraplaque hemorrhage. Univariate and multivariate Cox regressions were used to calculate the hazard ratio (HR) and corresponding 95% confidence interval (CI) of co-existing plaques in predicting subsequent vascular events.ResultsIn total, 150 patients (mean age: 61.8 ± 11.9 years; 109 males) were recruited. During the median follow-up time of 12.1 months, 41 (27.3%) patients experienced vascular events. Co-existing intracranial artery stenosis and extracranial carotid plaque (HR, 3.57; 95% CI, 1.63–7.82; P = 0.001) and co-existing intracranial artery stenosis and extracranial carotid LRNC (HR, 4.47; 95% CI, 2.15–9.27; P < 0.001) were significantly associated with subsequent vascular events, respectively. After adjusted for confounding factors and carotid stenosis, these associations remained statistically significant (HR, 5.12; 95% CI, 1.36–19.24; P = 0.016 and HR, 8.12; 95% CI, 2.41–27.31; P = 0.001, respectively).ConclusionsThe co-existing cerebrovascular atherosclerotic diseases, particularly co-existing carotid lipid-rich necrotic core and intracranial stenosis, are independent predictors for subsequent vascular events.

Left Ventricular Morphology and Function as a Determinant of Pulmonary Hypertension in Patients with Severe Aortic Stenosis: Cardiovascular Magnetic Resonance Imaging Study.

Background and Objectives: The influence of cardiac magnetic resonance (CMR) derived left ventricular (LV) parameters on the prognosis of patients with aortic stenosis (AS) was analyzed in several studies. However, the data on the relations between the LV parameters and the development of pulmonary hypertension (PH) in severe AS is lacking. Our objectives were to evaluate the CMR-derived changes of the LV size, morphology, and function in patients with isolated severe AS and PH, and to investigate the prognostic impact of these parameters on elevated systolic pulmonary artery pressure (sPAP). Materials and Methods: Thirty patients with isolated severe AS (aortic valve area ≤1 cm2) underwent a 2D-echocardiography (2D echo) and CMR before aortic valve replacement. Indices of the LV mass and volumes and ejection fraction were analyzed by CMR. The LV global longitudinal (LV LGS) and circumferential strain (LV CS) were calculated using CMR feature tracking (CMR-FT) software (Medis Suite QStrain 2.0, Medis Medical Imaging Systems B.V., Leiden, The Netherlands). The LV fibrosis expansion was assessed using a late gadolinium enhancement sequence. PH was defined as having an estimated sPAP of ≥45 mm Hg. The statistical analysis as performed using SPSS version 23.0 (SPSS, Chicago, IL, USA) Results: 30 patients with severe AS were included in the study, 23% with severe isolated AS had PH (mean sPAP 55 ± 6.6 mm Hg). More severe LV anatomical and functional abnormalities were observed in patients with PH when compared with patients without PH—a higher LV end-diastolic volume index (EDVi) (140 [120.0–160.0] vs. 90.0 mL/m² [82.5–103.0], p = 0.04), larger LV fibrosis area (7.8 [5.6–8.0] vs. 1.3% [1.2–1.5], p = 0.005), as well as lower LV global longitudinal strain (GLS; −14.0 [−14.9–(−8.9)] vs. −21.1% [−23.4–(−17.8)], p = 0.004). By receiver–operating characteristic (ROC) curve analysis, LV EDVi > 107.7 mL/m² (Area Under the Curve (AUC) 95.7%), LV GLS < −15.5% (AUC 86.3%), and LV fibrosis area >5% (AUC 89.3) were found to be robust predictors of PH in severe AS patients. Conclusions: In patients with severe aortic stenosis, a larger end-diastolic LV volume, impaired LV global longitudinal strain, and larger LV fibrosis extent can predict the development of pulmonary hypertension.

Severe pulmonary regurgitation in adolescents with tetralogy of Fallot leads to increased longitudinal strain

ObjectivesPostoperative patients with tetralogy of Fallot (TOF) are often compromised by chronic pulmonary regurgitation and chronic right ventricular volume load. We sought to determine whether pulmonary regurgitation (PR) would affect right and left ventricle (RV and LV) strain.Materials and methodsThis cross-sectional analysis included 40 patients who had TOF with surgical repair, with an average follow-up period of 11.8 ± 3.0 years. Altogether, 44 healthy volunteers with similar age and gender distribution were recruited. A cardiovascular magnetic resonance imaging study with feature tracking analysis was performed on all patients and controls.ResultsRV peak longitudinal strain was increased in TOF patients with PR > 30 ml/m2 when compared to those with PR < 30 ml/m2 (− 22.5% ± 2.7% vs − 19.7% ± 3.5%, p = 0.018) and controls (p = 0.007). PR volume correlated with peak RV longitudinal strain (R = − 0.37, p = 0.030) and peak RV longitudinal strain rate (systolic: R = 0.37, p = 0.03; diastolic: R = 0.39, p = 0.021). The peak RV circumferential strain, from base to apex, increased more than in healthy controls (apex-base difference 7.6% ± 4.2% vs 3.3% ± 2.4%, p < 0.0001).ConclusionsPediatric patients with TOF and a severe pulmonary regurgitation show an enhanced longitudinal strain when compared to patients with milder regurgitation or to control subjects. In addition, mean RV circumferential strain of the patients is significantly enhanced compared to healthy individuals.

Incremental Predictive Value of Longitudinal Axis Strain and Late Gadolinium Enhancement Using Standard CMR Imaging in Patients with Aortic Stenosis.

To analyse the predictive ability and incremental value of left ventricular longitudinal axis strain (LAS) and late gadolinium enhancement (LGE) using standard cardiovascular magnetic resonance (CMR) imaging for the diagnosis and prognosis of severe aortic stenosis (AS) in patients with an indication for aortic valve replacement. We conducted a prospective study on 52 patients with severe AS and 52 volunteers. The evaluation protocol included standard biochemistry tests, novel biomarkers of myocardial fibrosis, 12-lead electrocardiograms and 24-hour Holter, the 6-minute walk test and extensive echocardiographic and CMR imaging studies. Outcomes were defined as the composite of major cardiovascular events (MACEs). Among AS patients, most (n = 17, 77.2%) of those who exhibited LGE at CMR imaging had MACEs during follow-up. Kaplan–Meier curves for event-free survival showed a significantly higher rate of MACEs in patients with LGE (p < 0.01) and decreased LAS (p < 0.001). In Cox regression analysis, only reduced LAS (hazard ratio 1.33, 95% CI (1.01 to 1.74), p < 0.01) and the presence of LGE (hazard ratio 11.3, 95% CI (1.82 to 70.0), p < 0.01) were independent predictors for MACEs. The predictive value increased if both LGE and reduced LAS were added to left ventricular ejection fraction (LVEF). None of the biomarkers of increased collagen turnover exhibited any predictive value for MACEs. LAS by CMR is an independent predictor of outcomes in patients with AS and provides incremental value beyond the assessment of LVEF and the presence of LGE.

Atrial mechanics and their prognostic impact in Takotsubo syndrome: a cardiovascular magnetic resonance imaging study.

The exact pathophysiology of Takotsubo syndrome (TTS) remains not fully understood with most studies focussing on ventricular pathology. Since atrial involvement may have a significant role, we assessed the diagnostic and prognostic potential of atrial cardiovascular magnetic resonance feature tracking (CMR-FT) in TTS. This multicentre study recruited 152 TTS patients who underwent CMR on average within 3 days after hospitalization. Reservoir [total strain εs and peak positive strain rate (SR) SRs], conduit (passive strain εe and peak early negative SRe), and booster pump function (active strain εa and peak late negative SRa) were assessed in a core laboratory. Results were compared with 21 control patients with normal biventricular function. A total of 20 patients underwent follow-up CMR (median 3.5 months, interquartile range 3-5). All patients were approached for general follow-up. Left atrial (LA) but not right atrial (RA) reservoir and conduit function were impaired during the acute phase (εs: P = 0.043, εe: P < 0.001, SRe: P = 0.047 vs. controls) and recovered until follow-up (εs: P < 0.001, SRs: P = 0.04, εe: P = 0.001, SRe: P = 0.04). LA and RA booster pump function were increased in the acute setting (LA-εa: P = 0.045, SRa: P = 0.002 and RA-εa: P = 0.004, SRa: P = 0.002 vs. controls). LA-εs predicted mortality [hazard ratio 1.10, 95% confidence interval (CI) 1.01-1.20; P = 0.037] irrespectively of established cardiovascular risk factors (P = 0.019, multivariate analysis) including left ventricular ejection fraction (LVEF) (area under the curve 0.71, 95% CI 0.55-0.86, P = 0.048). TTS pathophysiology comprises transient impairments in LA reservoir and conduit functions and enhanced bi-atrial active booster pump functions. Atrial CMR-FT may evolve as a superior marker of adverse events over and above established parameters such as LVEF and atrial volume.

Microvasculature and intraplaque hemorrhage in atherosclerotic carotid lesions: a cardiovascular magnetic resonance imaging study

BackgroundThe presence of intraplaque haemorrhage (IPH) has been related to plaque rupture, is associated with plaque progression, and predicts cerebrovascular events. However, the mechanisms leading to IPH are not fully understood. The dominant view is that IPH is caused by leakage of erythrocytes from immature microvessels. The aim of the present study was to investigate whether there is an association between atherosclerotic plaque microvasculature and presence of IPH in a relatively large prospective cohort study of patients with symptomatic carotid plaque.MethodsOne hundred and thirty-two symptomatic patients with ≥2 mm carotid plaque underwent cardiovascular magnetic resonance (CMR) of the symptomatic carotid plaque for detection of IPH and dynamic contrast-enhanced (DCE)-CMR for assessment of plaque microvasculature. Ktrans, an indicator of microvascular flow, density and leakiness, was estimated using pharmacokinetic modelling in the vessel wall and adventitia. Statistical analysis was performed using an independent samples T-test and binary logistic regression, correcting for clinical risk factors.ResultsA decreased vessel wall Ktrans was found for IPH positive patients (0.051 ± 0.011 min− 1 versus 0.058 ± 0.017 min− 1, p = 0.001). No significant difference in adventitial Ktrans was found in patients with and without IPH (0.057 ± 0.012 min− 1 and 0.057 ± 0.018 min− 1, respectively). Histological analysis in a subgroup of patients that underwent carotid endarterectomy demonstrated no significant difference in relative microvessel density between plaques without IPH (n = 8) and plaques with IPH (n = 15) (0.000333 ± 0.0000707 vs. and 0.000289 ± 0.0000439, p = 0.585).ConclusionsA reduced vessel wall Ktrans is found in the presence of IPH. Thus, we did not find a positive association between plaque microvasculature and IPH several weeks after a cerebrovascular event. Not only leaky plaque microvessels, but additional factors may contribute to IPH development.Trial registrationNCT01208025. Registration date September 23, 2010. Retrospectively registered (first inclusion September 21, 2010).NCT01709045, date of registration October 17, 2012. Retrospectively registered (first inclusion August 23, 2011).

Automated quality control in image segmentation: application to the UK Biobank cardiovascular magnetic resonance imaging study

BackgroundThe trend towards large-scale studies including population imaging poses new challenges in terms of quality control (QC). This is a particular issue when automatic processing tools such as image segmentation methods are employed to derive quantitative measures or biomarkers for further analyses. Manual inspection and visual QC of each segmentation result is not feasible at large scale. However, it is important to be able to automatically detect when a segmentation method fails in order to avoid inclusion of wrong measurements into subsequent analyses which could otherwise lead to incorrect conclusions.MethodsTo overcome this challenge, we explore an approach for predicting segmentation quality based on Reverse Classification Accuracy, which enables us to discriminate between successful and failed segmentations on a per-cases basis. We validate this approach on a new, large-scale manually-annotated set of 4800 cardiovascular magnetic resonance (CMR) scans. We then apply our method to a large cohort of 7250 CMR on which we have performed manual QC.ResultsWe report results used for predicting segmentation quality metrics including Dice Similarity Coefficient (DSC) and surface-distance measures. As initial validation, we present data for 400 scans demonstrating 99% accuracy for classifying low and high quality segmentations using the predicted DSC scores. As further validation we show high correlation between real and predicted scores and 95% classification accuracy on 4800 scans for which manual segmentations were available. We mimic real-world application of the method on 7250 CMR where we show good agreement between predicted quality metrics and manual visual QC scores.ConclusionsWe show that Reverse classification accuracy has the potential for accurate and fully automatic segmentation QC on a per-case basis in the context of large-scale population imaging as in the UK Biobank Imaging Study.

Association Between Ambient Air Pollution and Cardiac Morpho-Functional Phenotypes: Insights From the UK Biobank Population Imaging Study.

Exposure to ambient air pollution is strongly associated with increased cardiovascular morbidity and mortality. Little is known about the influence of air pollutants on cardiac structure and function. We aim to investigate the relationship between chronic past exposure to traffic-related pollutants and the cardiac chamber volume, ejection fraction, and left ventricular remodeling patterns after accounting for potential confounders. Exposure to ambient air pollutants including particulate matter and nitrogen dioxide was estimated from the Land Use Regression models for the years between 2005 and 2010. Cardiac parameters were measured from cardiovascular magnetic resonance imaging studies of 3920 individuals free from pre-existing cardiovascular disease in the UK Biobank population study. The median (interquartile range) duration between the year of exposure estimate and the imaging visit was 5.2 (0.6) years. We fitted multivariable linear regression models to investigate the relationship between cardiac parameters and traffic-related pollutants after adjusting for various confounders. The studied cohort was 62±7 years old, and 46% were men. In fully adjusted models, particulate matter with an aerodynamic diameter <2.5 μm concentration was significantly associated with larger left ventricular end-diastolic volume and end-systolic volume (effect size = 0.82%, 95% CI, 0.09-1.55%, P=0.027; and effect size = 1.28%, 95% CI, 0.15-2.43%, P=0.027, respectively, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm) and right ventricular end-diastolic volume (effect size = 0.85%, 95% CI, 0.12-1.58%, P=0.023, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm). Likewise, higher nitrogen dioxide concentration was associated with larger biventricular volume. Distance from the major roads was the only metric associated with lower left ventricular mass (effect size = -0.74%, 95% CI, -1.3% to -0.18%, P=0.01, per interquartile range increment). Neither left and right atrial phenotypes nor left ventricular geometric remodeling patterns were influenced by the ambient pollutants. In a large asymptomatic population with no prevalent cardiovascular disease, higher past exposure to particulate matter with an aerodynamic diameter <2.5 μm and nitrogen dioxide was associated with cardiac ventricular dilatation, a marker of adverse remodeling that often precedes heart failure development.

Intra-thoracic adiposity is associated with impaired contractile function in patients with coronary artery disease: a cardiovascular magnetic resonance imaging study.

The influence of visceral adiposity on left ventricular remodeling following coronary artery disease (CAD)-related events has not been examined to date. Using magnetic resonance imaging (MRI) we explored intra-thoracic fat volume (ITFV) and strain-based markers of adverse remodeling in patients with CAD. Forty-seven patients with known CAD (25 with prior MI, 22 without prior MI) were studied. ITFV was quantified using previously validated imaging techniques. Myocardial strain was derived from cine MRI using a validated 3D feature-tracking (FT) software. Segmental LGE quantification was performed and was used to incrementally constrain strain analyses to non-infarcted (i.e. remote) segments. Remote myocardial strain was compared to the non-MI control cohort and was explored for associations with ITFV. Mean age was 57 ± 13years with a mean BMI of 30.0 ± 6.2kg/m2 (range 20.3-38.4kg/m2). Patients with versus without prior MI had similar demographics and BMI (29.4 ± 4.4 vs. 30.4 ± 7.9kg/m2, p = 0.62). Patients with prior MI had lower mean peak strain than non-MI patients (p = 0.02), consistent with remote tissue contractile dysfunction. Inverse associations were identified between ITFV and mean peak strain in both the MI group (circumferential: r = 0.43, p = 0.03; radial: - 0.41, p = 0.04; minimum principal: r = 0.41, p = 0.04; maximum principal: r = - 0.43, p = 0.03) and non-MI group (circumferential: r = 0.42, p = 0.05; minimum principal: r=0.45, p = 0.03). In those with prior MI higher ITFV was associated with a greater reduction in remote tissue strain. ITFV is associated with contractile dysfunction in patients with CAD. This association is prominent in the post-MI setting suggesting relevant influence on remote tissue health following ischemic injury. Expanded study of intra-thoracic adiposity as a modulator of myocardial health in patients with CAD is warranted.