Right ventricular diastolic function in aging: a head-to-head comparison between phase-contrast MRI and Doppler echocardiography.

To evaluate right ventricle (RV) diastolic function from phase-contrast MRI (PC-MRI) in aging. 89 healthy individuals (50 men, 43 ± 15 years) underwent cardiac MRI including 2D PC-MRI (1.5T) and reference Doppler echocardiography of both ventricles on the same day. Conventional echocardiographic parameters were estimated: early (E, cm/s) and atrial (A) peak velocities as well as myocardial early peak longitudinal velocity (E'). PC-MRI images were analyzed using custom software, providing: E', E and A waves along with respective peak flow rates (Ef, Af, mL/s) and filling volume (mL), for both ventricles. Intra- and inter-observer reproducibility was studied in 30 subjects and coefficients of variation (CoV) as well as intra-class correlation coefficients (ICC) were provided. RV diastolic function indices derived from PC-MRI data were reproducible (CoV ≤ 21%, ICC ≥ 0.75) and reliable as reflected by significant associations with left ventricular diastolic function indices assessed using both echocardiography (linear regression Pearson correlation coefficient r ≤ 0.59) and PC-MRI (r ≤ 71). Despite the fair associations between RV echocardiography and PC-MRI (r ≤ 0.25), the highest correlation with age was obtained for MRI Ef/Af ratio (r = - 0.64, p < 0.0001 vs. r = - 0.40, p = 0.0001 for echocardiographic E/A). Among PC-MRI E/A ratios, highest correlations with age were observed for flow rate and mean velocity ratios (r = - 0.61, p < 0.0001) as compared to maximal velocity ratios (r = - 0.56, p < 0.0001). Associations with age for E' were equivalent between PC-MRI (mean velocity: r = - 0.40, p < 0.0001; maximal velocity: r = - 0.36, p = 0.0005) and echocardiography (r = - 0.36, p = 0.0006). Finally, the significant and age-independent associations between RV mass/end-diastolic volume and E' were stronger for PC-MRI (mean velocity: r = - 0.36, p = 0.0006; maximal velocity: r = - 0.28, p = 0.007) than echocardiography (r = - 0.09, p = 0.38). PC-MRI tricuspid inflow and annulus myocardial velocity parameters were reproducible and able to characterize age-related variations in RV diastolic function.

Head-to-head comparison of the diagnostic performance of coronary computed tomography angiography and dobutamine-stress echocardiography in the evaluation of acute chest pain with normal ECG findings and negative troponin tests: A prospective multicenter study.

OBJECTIVE: To perform a head-to-head comparison of coronary CT angiography (CCTA) and dobutamine-stress echocardiography (DSE) in patients presenting recent chest pain when troponin and ECG are negative. METHODS: Two hundred seventeen patients with recent chest pain, normal ECG findings, and negative troponin were prospectively included in this multicenter study and were scheduled for CCTA and DSE. Invasive coronary angiography (ICA), was performed in patients when either DSE or CCTA was considered positive or when both were non-contributive or in case of recurrent chest pain during 6month follow-up. The presence of coronary artery stenosis was defined as a luminal obstruction >50% diameter in any coronary segment at ICA. RESULTS: ICA was performed in 75 (34.6%) patients. Coronary artery stenosis was identified in 37 (17%) patients. For CCTA, the sensitivity was 96.9% (95% CI 83.4-99.9), specificity 48.3% (29.4-67.5), positive likelihood ratio 2.06 (95% CI 1.36-3.11), and negative likelihood ratio 0.07 (95% CI 0.01-0.52). The sensitivity of DSE was 51.6% (95% CI 33.1-69.9), specificity 46.7% (28.3-65.7), positive likelihood ratio 1.03 (95% CI 0.62-1.72), and negative likelihood ratio 1.10 (95% CI 0.63-1.93). The CCTA: DSE ratio of true-positive and false-positive rates was 1.70 (95% CI 1.65-1.75) and 1.00 (95% CI 0.91-1.09), respectively, when non-contributive CCTA and DSE were both considered positive. Only one missed acute coronary syndrome was observed at six months. CONCLUSIONS: CCTA has higher diagnostic performance than DSE in the evaluation of patients with recent chest pain, normal ECG findings, and negative troponine to exclude coronary artery disease.

New estimate of valvuloarterial impedance in aortic valve stenosis: A cardiac magnetic resonance study.

PURPOSE: Valvuloarterial impedance (ZVA ), estimating left ventricle (LV) afterload, has been proposed in transthoracic echocardiography (TTE) as a predictor of mortality in aortic valve stenosis (AVS). However, its calculation differs from arterial characteristic impedance (ZC ). Our aim was to apply the concept of ZC calculation to estimate ZVA from MR with carotid tonometry and to evaluate these indices through their associations with symptoms, LV diastolic function and aortic stiffness. MATERIALS AND METHODS: In 40 patients with AVS (76 ± 13 years), ZVA-TI derived from velocity time integral and E/Ea were estimated by TTE. ZVA-INS , based on ZC formula, calculated as the instantaneous pressure gradient to peak flow ratio and aortic compliance were estimated by using MRI at 1.5 Tesla. RESULTS: Both ZVA estimates were higher in symptomatic than asymptomatic patients (707 ± 22 versus 579 ± 53 dyne.s/cm5 , P = 0.031 for ZVA-INS and 4.35 ± 0.16 versus 3.33 ± 0.38 mmHg.m2 /mL, P = 0.018 for ZVA-TI ). Although they were both associated with aortic compliance (r = -0.45; P = 0.006 for ZVA-INS and r = -0.43; P = 0.008 for ZVA-TI ) only ZVA-INS was associated with E/Ea (r = 0.50; P < 0.001). In multivariate analysis to identify determinants of E/Ea, a model including age, mean blood pressure, LV ejection fraction, LV mass, and aortic valve area was performed (R2 = 0.41; P < 0.01). When ZVA-INS was added to the model, its overall significance was higher R2 = 0.56 (P < 0.01) and ZVA-INS and LV mass were the only significant determinants. CONCLUSION: ZVA-INS was more strongly associated with diastolic dysfunction than usual parameters quantifying AVS severity. This new ZVA estimate could improve LV afterload evaluation. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:795-803.

Left atrial aging: a cardiac magnetic resonance feature-tracking study.

Importance of left atrial (LA) phasic function evaluation is increasingly recognized for its incremental value in terms of prognosis and risk stratification. LA phasic deformation in the pathway of normal aging has been characterized using echocardiographic speckle tracking. However, no data are available regarding age-related variations using feature-racking (FT) techniques from standard cine magnetic resonance imaging (MRI). We studied 94 healthy adults (41 ± 14 yr, 47 women), who underwent MRI and Doppler echocardiography on the same day for left ventricular (LV) diastolic function evaluation. From cine MRI, longitudinal strain and strain rate, radial motion fraction, and radial relative velocity, respectively, corresponding to the reservoir, conduit, and LA contraction phases, were measured using dedicated FT software. Longitudinal strain and radial motion fraction decreased gradually and significantly with aging for both reservoir (r > 0.31, P < 0.003) and conduit (r > 0.54, P < 0.001) phases, whereas they remained unchanged during the LA contraction phase. Subsequently, the LA contraction-to-reservoir ratio increased significantly with age (r > 0.44, P < 0.001). Longitudinal strain rate and radial relative velocity significantly decreased with age (reservoir: r = 0.39, P < 0.001, conduit: r > 0.54, P < 0.001), and these associations tended to be stronger in women than in men. Finally, associations of LA functional indexes with age were stronger in individuals with lower transmitral early-to-atrial maximal velocity ratio and mitral annulus maximal longitudinal velocity, as well as higher transmitral early maximal-to-mitral annulus maximal longitudinal velocity ratio, highlighting the LV-LA interplay. Age-related changes in LA phasic function indexes were quantified by cine MRI images using a FT technique and were significantly related to age and LV diastolic function.

Age-specific changes in left ventricular diastolic function: a velocity-encoded magnetic resonance imaging study.

OBJECTIVES: Our objectives were to assess the ability of phasecontrast MRI (PC-MRI) to detect sub-clinical age-related variations of left ventricular (LV) diastolic parameters and thus to provide age-related reference ranges currently available for echocardiography but not for MRI-PC, and to identify independent associates of such variations. METHODS: We studied 100 healthy volunteers (age = 42 ± 15years, 50 females) who had MRI with simultaneous blood pressure measurements. LV mass and volumes were assessed. Semiautomated analysis of PC-MRI data provided: 1) early transmitral (Ef) and atrial (Af) peak filling flow-rates (ml/s) and filling volume (FV), 2) deceleration time (DT), isovolumic relaxation time (IVRT), and 3) early myocardial longitudinal (E') peak velocity. RESULTS: MRI-PC diastolic parameters were reproducible as reflected by low coefficients of variations (ranged between 0.31 to 6.26 %). Peak myocardial velocity E' (r = -0.63, p < 0.0001) and flow-rate parameters were strongly and independently associated to age (Ef/Af:r = -0.63, DT:r = 0.46, IVRT:r = 0.44, Ef/FV:r = -0.55, Af/FV:r = 0.56, p < 0.0001). Furthermore, LV relaxation parameters (E', DT, IVRT), were independently associated to LV remodelling (LV mass/end-diastolic volume) and myocardial wall thickness (p < 0.01). CONCLUSIONS: PC-MRI age-related reference ranges of diastolic parameters are provided. Such parameters might be useful for a fast, reproducible and reliable characterization of diastolic function in patients referred for clinical MRI exam KEY POINTS: • MRI age-related reference values of left ventricular diastolic parameters are provided. • MRI diastolic parameters can characterise sub-clinical age-related variations in healthy individuals. • Diastolic function would complement cardiac MRI exam with currently neglected data. • Diastolic function would enhance MRI diagnostic value in cardiomyopathy and heartfailure.

Greater efficacy of aldosterone blockade and diuretic reinforcement vs. dual renin-angiotensin blockade for left ventricular mass regression in patients with resistant hypertension.

OBJECTIVES: We report the results of an echocardiographic substudy carried out in a trial comparing the effects of two different treatment strategies - mineralocorticoid receptor blockade (MRB) and dual renin-angiotensin system blockade (RASB) - in patients with resistant hypertension. Both strategies reduce left ventricular mass index (LVMI), but they have not been compared in patients with resistant hypertension. METHODS: After 4-week treatment with 300 mg irbesartan + 12.5 mg hydrochorothiazide + 5 mg amlodipine, 86 patients with resistant hypertension were randomized to the add-on 25 mg spironolactone (MRB group, n = 46) or 5 mg ramipril (RASB group, n = 40) groups for 12 weeks. Treatment intensity was increased at week 4, 8 or 10 if home blood pressure (BP) was equal to or above 135/85 mmHg, by sequentially adding 20-40 mg furosemide and 5 mg amiloride (MRB group), or 10 mg ramipril and 5-10 mg bisoprolol (RASB group). Transthoracic echography was performed at baseline and week 12. RESULTS: Daytime ambulatory BP decreased by 19 ±â€Š12/11 ±â€Š8 mmHg in the MRB group and by 8 ±â€Š13/7 ±â€Š7 mmHg in the RASB group (P = 0.0003/0.03). LVMI decreased by 8.2 ±â€Š18.9 g/m in the MRB group, whereas it increased by 1.8 ±â€Š19.1 g/m in the RASB group (P = 0.03). The decreases in posterior wall thickness, left ventricular (LV) end-systolic diameter, E/e' ratio and left atrial area were significantly greater with MRB than with RASB. The difference between groups remained significant after adjustment for the decrease in ambulatory BP. CONCLUSION: In patients with resistant hypertension, MRB-based treatment decreased both BP and LVMI more efficiently than a strategy based on dual RASB.

Evaluation of the impact of the recent controversy over statins in France: the EVANS study.

BACKGROUND: The effect of statins on the prevention of cardiovascular events is well-established. However, a recent controversy in France questioned the value of statins, especially in primary prevention. AIMS: To evaluate the impact of this controversy on patient adherence to statin therapy and its potential clinical impact. METHODS: All patients on statins were recruited consecutively from consultations over a period of 1 month (from March 2013) by five physicians in three centres. Patient demographics and co-morbidities were collected and adherence to statin therapy was evaluated with a questionnaire. We estimated the number of deaths and major cardiovascular events that could be induced per year. RESULTS: A total of 142 patients were included: 37 in primary prevention (mean age, 68.0±13.1 years; 41% women); 105 in secondary prevention (mean age, 67.6±12.1 years; 20% women). In primary prevention, 24.3% of patients intended to stop statins versus 8.6% in secondary prevention (P<0.001). In France, if the percentages of medication discontinuations following the controversy were actually similar to those we found in our survey, 4992 major cardiovascular events, including 1159 deaths, would be induced in 1 year. CONCLUSION: Recent controversy over statins could induce a large proportion of patients to stop their medication and generate a large number of major cardiovascular events.

Evaluation of aortic valve stenosis using cardiovascular magnetic resonance: comparison of an original semiautomated analysis of phase-contrast cardiovascular magnetic resonance with Doppler echocardiography.

BACKGROUND: Accurate quantification of aortic valve stenosis (AVS) is needed for relevant management decisions. However, transthoracic Doppler echocardiography (TTE) remains inconclusive in a significant number of patients. Previous studies demonstrated the usefulness of phase-contrast cardiovascular magnetic resonance (PC-CMR) in noninvasive AVS evaluation. We hypothesized that semiautomated analysis of aortic hemodynamics from PC-CMR might provide reproducible and accurate evaluation of aortic valve area (AVA), aortic velocities, and gradients in agreement with TTE. METHODS AND RESULTS: We studied 53 AVS patients (AVA(TTE)=0.87±0.44 cm(2)) and 21 controls (AVA(TTE)=2.96±0.59 cm(2)) who had TTE and PC-CMR of aortic valve and left ventricular outflow tract on the same day. PC-CMR data analysis included left ventricular outflow tract and aortic valve segmentation, and extraction of velocities, gradients, and flow rates. Three AVA measures were performed: AVA(CMR1) based on Hakki formula, AVA(CMR2) based on continuity equation, AVA(CMR3) simplified continuity equation=left ventricular outflow tract peak flow rate/aortic peak velocity. Our analysis was reproducible, as reflected by low interoperator variability (<4.56±4.40%). Comparison of PC-CMR and TTE aortic peak velocities and mean gradients resulted in good agreement (r=0.92 with mean bias=-29±62 cm/s and r=0.86 with mean bias=-12±15 mm Hg, respectively). Although good agreement was found between TTE and continuity equation-based CMR-AVA (r>0.94 and mean bias=-0.01±0.38 cm(2) for AVA(CMR2), -0.09±0.28 cm(2) for AVA(CMR3)), AVA(CMR1) values were lower than AVA(TTE) especially for higher AVA (mean bias=-0.45±0.52 cm(2)). Besides, ability of PC-CMR to detect severe AVS, defined by TTE, provided the best results for continuity equation-based methods (accuracy >94%). CONCLUSIONS: Our PC-CMR semiautomated AVS evaluation provided reproducible measurements that accurately detected severe AVS and were in good agreement with TTE.

How to calculate left ventricular mass in routine practice? An echocardiographic versus cardiac magnetic resonance study.

BACKGROUND: An accurate assessment of left ventricular (LV) mass is important for the detection of LV hypertrophy. AIMS: To assess the accuracy of four echocardiographic imaging modalities for assessing LV mass compared with cardiac magnetic resonance (CMR). METHODS: We prospectively studied 40 consecutive patients, who underwent an echocardiographic examination using four imaging modalities (M-mode fundamental imaging [FI], M-mode harmonic imaging [HI], two-dimensional [2D] FI and 2D HI) and CMR (our gold standard for LV mass measurement). All echocardiographic measurements were performed by two independent observers. RESULTS: All echocardiographic modes significantly overestimated LV mass compared with CMR (P≤0.04), except 2D FI (P=0.25). This overestimation was significantly higher with HI (up to 15.5%) compared with FI (up to 5.7%; P≤0.04). Significant correlations were observed between the different echocardiographic methods and the two observers. The interobserver agreement over LV mass measurement was lower with FI (intraclass coefficient [ICC] range, 0.66-0.73) than with HI (ICC range, 0.72-0.82), and the best agreement was obtained with 2D HI (ICC, 0.82). Good agreement between CMR and all echocardiographic methods was observed among the smallest LV diameters (ICC range, 0.62-0.85), but not among the largest LV diameters (ICC range, 0-0.22). CONCLUSIONS: HI overestimates LV mass compared with FI and CMR; this leads to overestimation of prevalence of LV hypertrophy in a population of hypertensive patients. HI improves interobserver reproducibility of LV mass measurement compared with FI, leading to a significant decrease in the number of patients required for clinical trials evaluating LV mass regression. Accuracy of LV mass measurement by echocardiography is affected by LV geometry.

Automated left ventricular diastolic function evaluation from phase-contrast cardiovascular magnetic resonance and comparison with Doppler echocardiography.

BACKGROUND: Early detection of diastolic dysfunction is crucial for patients with incipient heart failure. Although this evaluation could be performed from phase-contrast (PC) cardiovascular magnetic resonance (CMR) data, its usefulness in clinical routine is not yet established, mainly because the interpretation of such data remains mostly based on manual post-processing. Accordingly, our goal was to develop a robust process to automatically estimate velocity and flow rate-related diastolic parameters from PC-CMR data and to test the consistency of these parameters against echocardiography as well as their ability to characterize left ventricular (LV) diastolic dysfunction. RESULTS: We studied 35 controls and 18 patients with severe aortic valve stenosis and preserved LV ejection fraction who had PC-CMR and Doppler echocardiography exams on the same day. PC-CMR mitral flow and myocardial velocity data were analyzed using custom software for semi-automated extraction of diastolic parameters. Inter-operator reproducibility of flow pattern segmentation and functional parameters was assessed on a sub-group of 30 subjects. The mean percentage of overlap between the transmitral flow segmentations performed by two independent operators was 99.7 ± 1.6%, resulting in a small variability (<1.96 ± 2.95%) in functional parameter measurement. For maximal myocardial longitudinal velocities, the inter-operator variability was 4.25 ± 5.89%. The MR diastolic parameters varied significantly in patients as opposed to controls (p < 0.0002). Both velocity and flow rate diastolic parameters were consistent with echocardiographic values (r > 0.71) and receiver operating characteristic (ROC) analysis revealed their ability to separate patients from controls, with sensitivity > 0.80, specificity > 0.80 and accuracy > 0.85. Slight superiority in terms of correlation with echocardiography (r = 0.81) and accuracy to detect LV abnormalities (sensitivity > 0.83, specificity > 0.91 and accuracy > 0.89) was found for the PC-CMR flow-rate related parameters. CONCLUSIONS: A fast and reproducible technique for flow and myocardial PC-CMR data analysis was successfully used on controls and patients to extract consistent velocity-related diastolic parameters, as well as flow rate-related parameters. This technique provides a valuable addition to established CMR tools in the evaluation and the management of patients with diastolic dysfunction.