Florence Pontnau

Usefulness of maximal oxygen pulse in timing of pulmonary valve replacement in patients with isolated pulmonary regurgitation

Patients with pulmonary regurgitation after tetralogy of Fallot repair have impaired aerobic capacity; one of the reasons is the decreasing global ventricular performance at exercise, reflected by decreasing peak oxygen pulse. The aims of our study were to evaluate the impact of pulmonary valve replacement on peak oxygen pulse in a population with pure pulmonary regurgitation and with different degrees of right ventricular dilatation and to determine the predictors of peak oxygen pulse after pulmonary valve replacement. The mean and median age at pulmonary valve replacement was 27 years. Mean pre-procedural right ventricular end-diastolic volume was 182 ml/m2. Out of 24 patients, 15 had abnormal peak oxygen pulse before pulmonary valve replacement. We did not observe a significant increase in peak oxygen pulse after pulmonary valve replacement (p=0.76). Among cardiopulmonary test/MRI/historical pre-procedural parameters, peak oxygen pulse appeared to be the best predictor of peak oxygen pulse after pulmonary valve replacement (positive and negative predictive values, respectively, 0.94 and 1). After pulmonary valve replacement, peak oxygen pulse was well correlated with left ventricular stroke and end-diastolic volumes (r=0.67 and 0.68, respectively). Our study confirms the absence of an effect of pulmonary valve replacement on peak oxygen pulse whatever the initial right ventricular volume, reflecting possible irreversible right and/or left ventricle lesions. Pre-procedural peak oxygen pulse seemed to well predict post-procedural peak oxygen pulse. These results encourage discussions on pulmonary valve replacement in patients showing any decrease in peak oxygen pulse during their follow-up.

Characteristics and outcomes of heart failure-related hospitalization in adults with congenital heart disease

BACKGROUND Heart failure (HF) is the main cause of death in adult congenital heart disease (ACHD). AIMS We aimed to characterize HF-related hospitalization of patients with ACHD, and to determine HF risk factors and prognosis in this population. METHODS We prospectively included 471 patients with ACHD admitted to our unit over 24 months. Clinical and biological data and HF management were recorded. Major cardiovascular events were recorded for ACHD with HF. RESULTS HF was the main reason for hospitalization in 13% of cases (76/583 hospitalizations). Patients with HF were significantly older (median age 44±14 years vs. 37±15 years; P<0.01), with more complex congenital heart disease (P=0.04). In the multivariable analysis, pulmonary arterial hypertension (odds ratio [OR] 6.2, 95% confidence interval [CI] 3.5-10.7), history of HF (OR 9.8, 95% CI 5.7-16.8) and history of atrial arrhythmia (OR 3.6, 95% CI 2.2-5.9) were significant risk factors for HF-related admissions (P<0.001). The mean hospital stay of patients with HF was longer (12.2 vs. 6.9 days; P<0.01), and 25% of patients required intensive care. Overall, 11/55 (20%) patients with HF died, 10/55 (18%) were readmitted for HF, and 6/55 (11%) had heart transplantation during the median follow-up of 18 months (95% CI 14-20 months). The risk of cardiovascular events was 19-fold higher after HF-related hospitalization. CONCLUSIONS HF is emerging as a leading cause of morbidity and mortality in the ACHD population. Earlier diagnosis and more active management are required to improve outcomes of HF in ACHD.

Associations between native myocardial T1 and diastolic function evaluated by PC-CMR in patients with severe aortic valve stenosis

Background To assess the relationship between the presence of myocardial interstitial fibrosis as reflected by the increase in native T1 values and alterations in left ventricular (LV) diastolic function evaluated by phase contrast cardiac magnetic resonance (PC-CMR), in subjects with severe aortic valve stenosis (AVS). Methods We studied 20 subjects (71±10 years) with severe AVS including 19 with a preserved ejection fraction. All patients underwent transthoracic echocardiogram (TTE) and cardiac magnetic resonance (CMR) exams. CMR included conventional LV systolic function and delayed enhancement evaluations as well as a native T1 mapping acquisition using the modified Look-Locker inversion recovery sequence and velocity encoding data of the transmitral inflow for the evaluation of LV diastolic function. These latter CMR data were analyzed using custom software resulting in segmental T1 values and diastolic parameters such as transmitral peak velocities (E, A), peak flow rates (Ef, Af), filling volume (FV), and myocardial peak velocities. Results For all patients, TTE revealed the presence of severe AVS according to ESC criteria (aortic valve area indexed to BSA= 0.43±0.09 cm2/m2 and mean gradient 54 ±14mmHg). When compared to CMR data of 34 elderly controls (60±8 years) despite the preserved ejection fraction (patients=66±10%; controls=66±4%), diastolic parameters indicated an impaired LV relaxation in patients with severe AVS. Importantly, while dense fibrosis volume quantified from delayed enhancement images was not related to diastolic function parameters, a significant relation was found between native myocardial T1 values and parameters of LV filling such as: the ratio between the peak filling rate and the peak atrial rate EfMR/AfMR (r=0.51; p<0.05); the ratio between the peak atrial rate and the filling volume Af/FVMR (r=0.67; p<0.05); and the peak atrial rate Af (r=0.63; p<0.05). Conclusions Interstitial myocardial fibrosis assessed non-invasively by native T1 is related to the severity of diastolic dysfunction in subjects with severe AVS.

Asymptomatic aortic coarctation diagnosed because of large abdominal arterial collateral

An active 29-year-old man was referred to our institution for a severe hypertension (170/100 mmHg) despite monotherapy with nicardipine. Physical examination documented symmetric blood pressure with a normal pulse examination. Transthoracic echocardiography showed normal left ventricular function without significant hypertrophy, a tricuspid aortic valve and a normal ascending aorta. He underwent an enhanced computed tomography angiography (CTA) to rule out renal artery stenosis or adrenal pathology (normal renal arteries; Panel A: asterisk). Three-dimensional CTA reconstructions revealed widespread abdominal arterial collaterals and a relatively small abdominal aorta (Panels A and B) measuring 17 mm. As the abdominal collateral arterial network appeared connected to thoracic arterial collateral and in particular the left epigastric artery (Panels A, B and C: arrows), we suspected an aortic coarctation (AC). Therefore, we performed aortic magnetic resonance angiography (MRA) using a 1.5 T scanner (GE, USA), which confirmed a native AC with severe stenosis estimated at 75% in diameter (Panels D and F: arrowheads). No other indications of congenital heart disease were identified. Blood flow analysis of 4D flow MR phase contrast sequences using ArterysTM software (Arterys Inc., USA) demonstrated an abnormal decrease of systolic flow in the descending aorta compared to the ascending aorta. It also revealed high-velocity systolic–diastolic flows across the stenosis, with post-stenotic helical streamlines in the descending aorta (Panels E and F). Interestingly, 4D flow imaging documented enhanced flow in the left internal thoracic artery (Panel E: arrow). AC is a frequent congenital cardiovascular disease accounting for 6–8%1 of all congenital cardiovascular malformations. It is defined as a narrowing or constriction of the lumen of the aorta. Clinical presentation of affected patients depends on the site and extent of obstruction and associated cardiovascular anomalies. AC is typically diagnosed in early childhood, although identification may be delayed until adulthood when efficient compensatory collateral vessels exist. Survival to older age is rare owing to severe cardiovascular complications2 such as heart failure, coronary artery disease, aortic rupture/dissection, concomitant aortic valve disease, infective endarteritis/ endocarditis, or cerebral hemorrhage. The European Society of Cardiology guidelines recommend treatment Asymptomatic aortic coarctation diagnosed because of large abdominal arterial collateral

Accuracy and Inter observer variability of blood flow quantification on 4D flow MRI in adult with transposition of the great arteries corrected by arterial switch

Background 4D flow magnetic resonance imaging appears as a reliable tool for blood flow quantification. However, in patients with transposition of the great arteries corrected by arterial switch, the choice of a high velocity encoding (venc) to avoid velocity aliasing due to pulmonary stenosis, could decrease the accuracy of blood flow quantification in vessels such as superior or inferior vena cava (SVC, IVC) and atrio-ventricular valve (AVV) when blood velocities are lower. Moreover, such accuracy of blood flow estimates can further be influenced by user experience in cardiac imaging due to manual intervention for 3D segmentation process of cardiac structures and correction of background phase offset. Our aim was to investigate the accuracy and inter observer variability of quantitative MR 4D flow estimates in patients with transposition of the great arteries corrected by arterial switch (asTGA).

3D myocardial wall stress assessed by cardiac magnetic resonance and non invasive aortic blood pressure in patients with severe aortic valve stenosis

Methods We studied 20 subjects (71±10 years) with severe AVS including 19 with a preserved ejection fraction (EF) and 14 elderly controls (59±6 years). All subjects underwent within 4 hours, transthoracic echocardiogram (TTE) and cardiac magnetic resonance (CMR) as well as applanation tonometry of the carotid artery immediately after CMR examination. CMR included an ECG gated cine SSFP acquisition of left ventricular (LV) short axis slices, positioned regularly and without inter-slice gap between base and apex. Carotid tonometry, by adjusting by the mean brachial pressure obtained during CMR acquisition is a reliable measurement of central aortic blood pressure. 3D MWS can provide a LV afterload estimate which is well known to be strongly related to EF, except in case of depressed contractility. Evaluation of 3D MWS relied on the combination of: 1) a geometrical factor (GF), estimated according to myocardial thickness and LV cavity radius, while accounting for the 3D curvature of the LV, and 2) LV peak systolic pressure provided by tonometric measurement and Doppler maximal transvalvular pressure gradient. Results For all patients, TTE revealed the presence of severe AVS according to ESC criteria (aortic valve area indexed to BSA= 0.43±0.09 cm2/m2 and mean gradient 54±14mmHg). When compared to 3D MWS evaluation of controls, GF indicated a significant decrease in patients with AVS (patients AVS 0.28±0.16; controls 0.37±0.13; p<0.05) whereas 3D MWS remained equivalent between the two groups. These data reflect LV adaptation to pressure overload, leading to an overall normalization of MWS in severe AVSwith preserved EF. Furthermore, our 3D model of MWS is strongly related to EF (r=0.84; p<0.05), reflecting the robustness of this non-invasive method based on CMR and applanation tonometry.

Valsalva sinus asymmetry in bicuspid aortic valve: diameter through fused cusp is smaller than diameter through nonfused cusp but maximal diameter is the same whatever the phenotype when estimated by CMR

Background Previous studies establish a link between bicuspid aortic valve (BAV) morphology and aortic shape. Anteroposterior (AP) leaflets with right left (RL) fusion was found more often associated with dilatation of VS than left-right (LR) leaflets with either fusion between right and noncoronary(R-NC) cusps or between left and noncoronary cusps(L-NC). However, most of these studies were performed by transthoracic echocardiography with parasternal long axis view measurements without taking into account a possible valsalva sinus (VS) asymmetry. The aim of our study was to assess aortic valsalva sinus size and morphology by CMR in a large cohort of BAV subjects.

P1 Aortic root dilatation and stiffness assessed by magnetic resonance imaging in adults with repaired tetralogy of Fallot

We aimed to assess dimensions and biomechanics of the thoracic aorta in patients with surgically repaired tetralogy of Fallot (TOF), using Cardiac Magnetic Resonance (CMR). Aortic root dilatation frequently occurs in TOF and can lead to aortic regurgitation (AR), aortic aneurysms and its complications. Histological studies in TOF have shown abnormalities of the aortic media that can predis-pose to aortic root dilatation. 50 patients (aged 29±12 years) with repaired TOF and 50 control healthy subjects (aged 29±11 years) matched for age and sex underwent CMR imaging, with standard cine and velocity sequences. The aortic root dimensions were assessed at end-diastole at the following levels: aortic annulus, sinus of Valsalva, sinotubular junction (STJ), ascending and descending aorta. Aortic elasticity was evaluated by aortic distensibility and pulse wave velocity (PWV). CMR included conventional left ventricle (LV) and right ventricle (RV) systolic function and volume study, AR fraction measure. Diameters of the aorta indexed to the body surface area were significantly increased in TOF compared to controls at level of sinus of Valsalva (22.6±3.8 vs 17.0±2.0mm/m 2; p