[Tricuspid regurgitation: transcatheter treatment by TriClip®]

Tricuspid regurgitation (TR) is not rare and has been associated with poor clinical outcomes when severe. The etiology of TR is functional in most cases and is usually associated with left-sided valvular heart disease. Severe TR is responsible for right heart failure and may evolve to global heart failure. Current echocardiographic classification includes several grades (trivial, moderate, severe, massive, torrential TR) which influence patients' prognosis in an incremental manner. Management of patients with severe TR is discussed in Heart Team after evaluation of surgical risk. The TRI-SCORE may be used to evaluate the intra-hospital mortality risk in case of isolated tricuspid surgery. Isolated TR surgery is rarely performed as surgical risk outweighs expected clinical benefits. Transcatheter treatment of severe TR may be considered in highly selected cases. Transcatheter edge-to-edge repair (TEER) restores leaflets coaptation. First tricuspid TEER procedures were performed with the MitraClip® (Abbott, Santa Clara, CA, USA) device, but a specific device has been developed: the TriClip® (Abbott). The prospective multicenter TRILUMINATE trial evaluated the TriClip® procedure in patients with symptomatic moderate to severe TR and high surgical risk. The results show a good efficacy with reduction of post-procedural TR grade and increase in NYHA functional class, 6-minute walking test distance, right ventricular function, and quality of life at 1 year. Other devices are currently being evaluated or in development (i.e., transcatheter tricuspid implantation). Non-surgical TR management is likely to evolve and improve significantly soon.

Cardiac amyloidosis: a review of the literature

Cardiac amyloidosis is a rare disease associated with severe morbidity and mortality. There are three main types of amyloidosis associated with cardiac involvement: light chain (AL), familial or senile (ATTR) and secondary amyloidosis (AA). Cardiac amyloidosis often results in heart failure with preserved left ventricular ejection fraction, may display echocardiographic features of restrictive cardiomyopathy associated with left ventricular hypertrophy or mimic hypertrophic obstructive cardiomyopathy. However, left ventricular systolic dysfunction and normal wall thickness can sometimes be encountered. Imaging studies (echocardiography, bone scintigraphy, cardiac magnetic resonance) and blood and urine analysis are usually the main tools for the diagnosis. Sometimes, a tissue biopsy may be necessary. Treatment, which is constantly improving, will be carried out on two fronts: treatment of the symptoms and complications that the disease already caused and prevention of additional amyloid deposits while managing the concomitant complications. The purpose of this article is to review the management of cardiac amyloidosis.

The impact of an ultra-trail on the dynamic of cardiac, inflammatory, renal and oxidative stress biological markers correlated with electrocardiogram and echocardiogram

The aim of this study was to describe the effects of a 64.2 km ultra-trail on the biomarkers of muscle damage, inflammation and oxidative stress, and compare the results observed with an ECG and an echocardiogram, both performed before and after the race.Thirty-three ultra-trail volunteers (45.8 ± 8.7 years old) were enrolled in our study. Three blood tests were drawn from each runner, one just before (TPRE), one just after (TPOST) and the last 3 h after the end of the race (TPOST3h).All the markers increased. The maximum concentrations observed were at TPOST3h and were significant (p < 0.001) for creatine kinase, creatine kinase isoform MB, high-sensitivity C-reactive protein, uric acid and for the ratio of reduced glutathione to oxidised glutathione. However, in the case of myoglobin, high-sensitive troponin T, N-terminal pro-brain natriuretic peptide, oxidised glutathione, myeloperoxidase, cystatin C and creatinine, the most significant increases were at TPOST (p < 0.001). Modifications were observed in the medical imaging using echocardiography such as reduction of left ventricule end-sytolic and diastolic volumes and left ventricular global longitudinal strain. ECG showed electrical criteria for left ventricular hypertrophy and incomplete right bundle branch block after the race.Endurance races cause significant physiological stress to the body that can be measured by the increase of different biomarkers. From a laboratory perspective, it is important to take into account the possible exercise performed previous to the testing to avoid a misinterpretation of the results. From a training perspective, due to these increases in biomarkers, it is recommended that runners wait at least 72 h after an ultra-trail before subsequent training. In addition a transient impairment of ventricular function due to dehydration were observed.

[Dynamic mitral regurgitation and acute pulmonary edema]

We report the case of a 61-year old patient with signs and symptoms of heart failure with mid-range left ventricular ejection fraction and moderate mitral regurgitation of mixed etiology (rheumatic heart disease, toxic and ischemic). The dynamic behaviour of the mitral regurgitation was revealed by an acute episode of pulmonary edema in the context of an abrupt elevation of blood pressure inducing an increase in left ventricular afterload. Dynamic mitral regurgitation must be considered in any patient with exercise dyspnea who has a moderate mitral regurgitation in resting conditions or in patients with repeated acute pulmonary edema without an obvious cause. Exercise stress echocardiography is the best diagnostic test to explore the dynamic behaviour of the mitral regurgitation. Surgery or percutaneous treatment may be proposed in severe cases.

Layer-specific strain and the degree of left ventricular thickness in patients with hypertrophic cardiomyopathy

Background

Left ventricular (LV) wall thickness is an important parameter for the diagnosis of hypertrophic cardiomyopathy (HCM) and is also associated with long-term clinical outcome in HCM patients. However, conventional tools have failed to analyze the mechanisms of structural and functional abnormalities that occur at the cellular level in hypertrophied myocardial tissue. Recently, technological progression of 2D-speckle tracking echocardiography (2D-STE) has enabled the estimation of layer-specific strain (LSS), such as epicardial, mid-myocardial, and endocardial longitudinal strain, respectively. LSS may have the potential to elucidate the detailed mechanisms of myocardial dysfunction.

Purpose

The aim of this study was (i) to clarify the detailed mechanisms of structural and functional abnormalities of myocardial tissue in HCM using LSS (ii) to investigate the diagnostic accuracy of LSS for HCM.

Methods

Forty-one patients with HCM and preserved LV ejection fraction (LVEF) (66% male, 52±18 years, LVEF 62.9±3.7%) and 41 controls matched for age and sex (66% male, 52±20 years, LVEF 63.5±8.2%) underwent 2D-STE (GE-Healthcare, Vivid-E9). Quantitative strain values of epicardial, mid-myocardial, and endocardial layers were measured.

Results

LV wall thickness including interventricular septum thickness (HCM vs. Controls; 18.9±5.0 vs. 9.1±1.8, p&lt;0.001), posterior wall thickness (11.5±2.5 vs. 8.8±1.9, p&lt;0.001), and maximum wall thickness (20.1±4.3 vs. 9.4±0.4, p&lt;0.001) were significantly lower in HCM than in Controls. Absolute values of LSS for all layers were lower in HCM than in Controls (HCM vs. Controls; epicardial; −13.1±3.3 vs. −19.5±1.6, p&lt;0.001; mid-myocardial; −15.8±3.3 vs. −21.4±1.7, p&lt;0.001; endocardial; −18.9±3.9 vs. −23.6±1.9, p&lt;0.001). End/Epi ratio was higher in HCM than in Controls (HCM vs. Controls; 1.5±0.2 vs. 1.2±0.0, p&lt;0.001). Next, we investigated the echocardiographic parameters that correlated with LV maximal wall thickness (MWT). End/Epi ratio was an independent predictor of LV MWT (β=0.96, p&lt;0.001). Receiver operating characteristic analysis revealed that a higher End/Epi ratio (≥1.3) was the strongest predictor of diagnostic criteria for HCM (LV wall thickness ≥15 mm) (area under the curve 0.99, p&lt;0.001, sensitivity 98%, specificity 97%).

Conclusions

In HCM patients with preserved LVEF, (i) LSS was lower and End/Epi ratio was higher than in controls. (ii) End/Epi ratio (≥1.3) was the strongest predictor of abnormal wall thickness of HCM. The mechanism of higher End/Epi ratio in HCM might be attributable to the more common myofibrillar disarray in mid- and epicardial layers. Variations of LSS represented by End/Epi ratio might have the potential to accurately detect HCM and to elucidate the pathophysiology of impaired LV wall motion at cellular level in HCM.

Funding Acknowledgement

Type of funding source: None

P938 Myocardial work analysis in hypertrophic cardiomyopathy: low work or high work?

Background

Myocardial Work (MW) is an interesting novel non-invasive parameter to evaluate cardiac performance by left ventricle (LV) pressure-strain loops.

Purpose

The present study sought to investigate MW in patients with both non-obstructive (NOHCM) and obstructive hypertrophic cardiomyopathy (OHCM).

Methods

Forty-four patients with hypertrophic cardiomyopathy (HCM) and twenty controls (mean age 53 ± 20 years vs 52 ± 17 years, respectively, p = 0.8) underwent standard two-dimensional and speckle-tracking echocardiography. Global Work Index (GWI), global constructive work (GCW), global work waste (GWW) and global work efficiency (GWE) were estimated by LV pressure-strain loops. In OHCM group, MW was evaluated by adding LVOT peak gradient to SBP. Analysis of multilayer LV longitudinal strain (LS) and left atrial (LA) LS was performed.

Results

Global LS (GLS), endocardial LS, epicardial LS and LA LS were significantly reduced in patients compared to controls (p &lt; 0.001 for all). All patient population had significantly lower GWI, GCW and GWE and higher GWW respect to controls. Regional GLS, endocardial LS, epicardial LS and regional WI were significantly reduced in hypertrophic area compared to no-hypertrophic area in the patient population (p &lt; 0.001 for all). OHCM group ( n = 14) had higher values of GWI and GCW compared to NOHCM ( n = 30) (2160 (1877-2250) vs 1547 (1148-1767)mmHg% and 2285 ± 411 vs 1755 ± 584 mmHg% respectively, p &lt; 0.05 for both, Figure).

Conclusions

GWI and GCW are reduced in patients with NOHCM. Patients with OHCM, have higher GWI and GCW compared to non-obstructive ones, as expression of work at higher level of energy necessary to counteract high afterload. Our proposed method to estimate MW in OHCM needs to be validated in invasive studies.

Abstract P938 Figure.

P1404 Additional power of automated longitudinal strain during dobutamine stress echo for detecting inducible ischemia in left anterior descending artery stenosis

Background

Dobutamine stress echo (DSE) is a sensitive but subjective test of inducible ischemia. Speckle tracking allows now a quantitative assessment of regional wall motion, even during DSE.

Purpose

To investigate the feasibility and accuracy of global and regional longitudinal strain during DSE to detect significant CAD.

Methods

This is a prospective, observational study, including 88 patients undergoing DSE for suspected CAD. Thirthy-three patients with negative DSE were excluded from analysis. The remaining 50 patients (82% males, mean age 66.3 ± 8.2 years) with positive DSE underwent subsequent invasive coronary angiography (CA). Besides visual regional wall motion score index (WMSI), global longitudinal strain (GLS) and regional longitudinal strain (RLS) were determined at rest, at peak stress and at early recovery by a dedicated software (Automated Function Imaging) incorporated in a quoad-screen of the echo machine and activated by automatic quantification. Obstructive CAD was defined as &gt;70% stenosis or intermediate stenosis combined with fractional flow reserve &lt;0.80.

Results

The feasibility of DES regional longitudinal strain was 100% (n = 50/50) in the pooled population. Fifteen patients did not show coronary stenosis whereas obstructive CAD was detected in 35 patients (12 with multi-vessel disease). Among these patients, 18 patients had left anterior descending artery (LAD) stenosis, 18 left circumflex coronary artery (LCX) stenosis and 15 right coronary artery (RCA) stenosis. GLS reduction at peak stress (k = 0.253, p = 0.037) and WMSI increase at peak stress (k = 0.217, p = 0.04) showed mild but significant agreement with CA for detecting significant coronary stenosis, whereas the agreement of GLS at recovery (k=-0.087, p = 0.518) was poor. When single lesion territory was considered, GLS at peak stress (17.4 ± 5.5 vs 20.5 ± 4.4%, p = 0.034) and LAD longitudinal strain (= average of 8 myocardial segments: middle and apical posterior septum, basal, middle and apical anterior septum, basal, middle and apical anterior wall) at peak stress showed significantly lower values in the obstructed LAD regions than the territories perfused by non-obstructed coronary arteries (17.1 ± 7.6 vs 21.6 ± 5.5% p = 0.021). Conversely, in presence of significant LCX or RCA stenosis, visual regional wall motion of LCX and RCA territories were higher at peak stress (WMSI LCX = 1.80 ± 0.65 in presence of LCX stenosis vs. 1.38 ± 0.44 in absence of stenosis, p &lt; 0.01; WMSI RCA = 1.89 ± 0.52 in presence of RCA stenosis vs. 1.42 ± 0.42 in absence of stenosis, p = 0.002), but RLS at peak stress showed a trend to increase, without achieving the statistical significance (RLS RCA: p = 0.128, RLS LCX: p = 0.103).

Conclusion

AFI-based strain quantitative analysis appears to be highly feasible during DSE. It appears also to be more accurate than the visual wall motion for the detection of myocardial ischemia in presence of LAD while the accuracy is suboptimal in patients with LCX and RCA stenosis.

P5981Impact of radiotherapy on myocardial function and paravalvular leaks after transcatheter aortic valve implantation (TAVI)

Introduction

Thanks to the anticancer therapies, the life expectancy of the oncologic patients has noticeably increased, but several cardiac diseases can be observed in these patients as the result of the cardiotoxic effects.

Purpose

To investigate the impact of radiotherapy on the clinical and echocardiographic outcomes, in patients with severe aortic stenosis (AS) and preserved left ventricle ejection fraction (LVEF) treated with transcatheter aortic valve implantation (TAVI).

Methods

We recruited patients with severe AS and left ventricular ejection fraction (LVEF) ≥50‰ treated with TAVI and who received prior radiotheraphy. Patients with LVEF <50‰, treated with valve in valve, with inadequate acoustic windows or the absence of echocardiographic images pre-TAVI and after 3–6 months were excluded. Demographic, clinical and echocardiographic data were recorded.

Results

102 patients were included in the present analysis. They were divided in two groups: 19 (18‰) with an oncologic history treated with previous left thoracic/mediastinal radiotherapy and 83 (82‰) patients without an oncologic history. The two groups were homogeneous in terms of demographic and clinical data, brain natriuretic peptide (BNP), echocardiographic data pre-TAVI. They only differed for a greater prevalence of mitral stenosis and calcifications in the oncologic patients versus the non-oncologics (respectively 36‰ vs. 12‰ p=0,016; 73‰ vs. 29‰ p=0,001). No differences in terms of in-hospital clinical outcomes were observed. The echocardiographic evaluation in both groups showed a significant decrease of the peak velocities and of the transprosthetic gradients. There was a higher incidence of at least moderate degree paraprosthetic leaks in the oncologic group vs. the non-oncologic one: 6 (31‰ total leaks, 37‰ leaks >2+) vs. 7 (8‰ total leaks, 12‰ leaks >2+); p=0.029. After 3–6 months, there was not a statistically significant improvement of ejection fraction (EF) in neither of the two groups but there was a statistically significant improvement of transmural, subepicardial and subendocardial longitudinal strain values in the non-oncologic group compared to pre-TAVI values, respectively −19±4 vs. −17±4 (p<0.001); −17±3 vs. −15±3 (p<0.001); −22±4 vs. −19.8±4 (p<0.001). Any statistically significant improvement was detected in the group with history of anticancer treatments between the longitudinal strain values post and pre-TAVI (−18±3‰ vs. −16±3‰; −14±3‰ vs. −20±5‰; −20 ±± 5‰ vs. −19±4‰).

Conclusions

Patients affected by severe AS treated with TAVI and who received received prior radiotheraphy, showed the absence of statistically significant improvement of multilayer strain values, at 3–6 months after TAVI. Oncologic patients also had a higher incidence of haemodynamically relevant paravalvular leaks after the intervention, compared to the non-oncologic patients.

[Percutaneous left atrial appendage occlusion for thromboembolism protection in patients with atrial fibrillation]

Atrial fibrillation (AF) is the most common clinical arrythmia and can be associated with severe thromboembolic complications. For different reasons, a large number of AF patients who would benefit from oral anticoagulation (OAC) are not treated. In case of contra-indications to long-term OAC, left atrial appendage (LAA) closure allows the exclusion of the LAA from the systemic circulation and significantly reduces the thromboembolism risk. Results from large randomized trials show that this technique is non-inferior in terms of efficacy compared to OAC and that it can significantly reduce the rate of haemorrhagic complications. Large-scale registries show promising results in patients with contra-indications to long-term OAC. Clinical trials are under way to define the role and spectrum of LAA occlusion and to optimize post-procedural treatment.

[The heart team : definition and organization. Point of view of the cardiologist]

The management of complex cardiovascular disease has changed considerably with the development of new care strategies. In cardiology, the «Heart Team» or literally «Equipe du cœur» occupies a prominent place in the latest European and American recommendations, particularly in the management of complex coronary or valvular diseases and in heart failure patients. The concept of «Heart Team» is based on the need for a multidisciplinary holistic approach based on evidence (respect of the recommendations of the scientific societies), the patient as a whole (comorbidities, preferences), risks and long-term benefits of the treatment selected and performed, as well as on the level of local expertise. It aims to determine the best management strategy for the patient, and perhaps to guarantee a better result (prognosis).

[Alcohol septal ablation for obstructive hypertrophic cardiomopathy]

Alcohol septal ablation has become an attractive alternative to surgical myomectomy in symptomatic patients with obstructive hypertrophic cardiomyopathy. Its purpose is to achieve a therapeutic infarction in the sub-aortic territory responsible of the obstruction. It is indicated in symptomatic patients resistant to optimal medical treatment and having a left intraventricular gradient equal or higher than 50 mmHg, spontaneous or with exercise. The selection of candidates must be rigorous and the procedure must be performed in an experienced center, associating interventionalists and echocardiographists. Alcohol septal ablation is preferred in cases of favourable coronary anatomy, sub-aortic obstruction and absence of associated mitral valve defect. The septal alcohol technique is fast, effective and safe. The per-procedural contrast echocardiography helps identifying whether the myocardial segment is vascularized by the septal branch to be occluded. The benefits of alcohol septal ablation are comparable to those seen with surgical myectomy in terms of functional class, exercise capacity, and gradient regression. The morbidity and mortality observed in the short and mid terms are globally equivalent to that of the surgical intervention. The major complication is dominated by the occurrence of complete atrioventricular block requiring the implantation of a definitive pacemaker, a complication in sharp decline since the contrast ultrasound-guided technique has become widespread.

[Percutaneous closure of paravalvular leak]

Paravalvular leaks (PVL) are a serious complication after surgical or transcatheter aortic valve replacement. They are mostly small and unimportant. When they manifest clinically (1 to 5 % of PVL), they can become responsible for severe hemolytic anaemia or cause congestive heart failure. For years, surgical re-intervention has been considered the treatment of choice for symptomatic patients with PVL. However, surgical re-intervention is associated with a high risk of morbidity and mortality. Percutaneous PVL closure is a less invasive alternative to surgical re-intervention. The safety and feasibility of percutaneous PVL closure has been confirmed in several studies. In this article, we discuss the issue of PVL and their percutaneous management.

[Percutaneous mitral interventions]

After aortic valve diseases, mitral valve diseases represent the most numerous indications of surgical or percutaneous valvular intervention. Surgical management is favoured in severe symptomatic mitral regurgitation. In case of high or prohibitive surgical risk, new techniques are developed to allow percutaneous, less invasive management. In these circumstances, MitraClip® allows the treatment of mitral regurgitation in case of adequate valve morphology. Percutaneous balloon valvuloplasty is currently the first-line treatment of mitral stenosis related to rheumatic disease when anatomical features are favourable. Alongside the Inoue technique, which remains the classical procedure, other approaches are available with encouraging results.

[Non-invasive imaging and interventional cardiology]

In the last decades, interventional cardiology has received fast and wide implementation as an effective alternative treatment to surgery for several congenital and acquired diseases. Imaging provides solutions for most clinical needs, from diagnosis to prognosis and risk stratification, as well as anatomical and functional assessment. In this article, we present recent innovations in medical imaging for structural heart disease and coronary artery disease, emphasizing the progress achieved in the field of multimodality imaging. Intra-procedural guidance can be facilitated by established multimodality cardiac imaging such as transesophageal 2D and 3D echocardiography and by novel techniques as echo-fluoroscopy overlay and 3D imaging fusion. Computed tomography and magnetic resonance imaging are particularly helpful for preprocedural morphology assessment and device sizing. Successful planning, guidance, and monitoring of interventions depend heavily on accurate imaging for both structural heart disease and complex coronary artery disease.

[Pulmonary arterial hypertension]

Pulmonary arterial hypertension (PAH) is a rare vascular lung disease with a complex etiopathogeny characterized by an increased pulmonary arterial pressure of 25 mmHg or above assessed by right heart catheterization. The diagnosis is difficult due to the atypical presentation with shortness of breath requiring a sequential approach bringing at the end the clinician to perform a right heart catheterization. Nowadays, several therapies have proven to be efficient for treating PAH. Recently, international recommendations have moved to an initial combination therapy reducing the overall morbi-mortality of the patients. Therefore, early therapy appears to be a priority in PAH underlying the need for increasing the global knowledge around PAH.

[Infective endocarditis:an emergency well too minimized]

Infective endocarditis is a rare disease that can lead to some diagnostic wandering because of its often nonspecific and polymorphic clinical manifestations. This latency is at the origin of severe cardiac and extra-cardiac complications, yet highly fatal. The clinician should always bear in mind the differential diagnosis of a patient with fever of undetermined origin, with risk factors for valve infection such as foreign material, and history recent invasive procedures (including dental procedures) or recent hospitalization. The current medical tools make it possible to highlight the infection and its complications in a fast and complete manner, so as not to delay the patient's management, particularly with the introduction of urgent empirical antibiotherapy.

[European society of cardiology guidelines for the management of infective endocarditis (partim 1)]

Until recently, the recommendations of infective endocarditis were based on expert opinions, due to its low incidence and the absence of controlled trials. The update in 2015 of the new guidelines of the European Society of Cardiology (compared with 2009) relates to the publication of a randomised study on the surgical treatment, the innovations in imaging procedures (especially functional imaging in nuclear medicine) and the new concept of «Team Endocarditis» (multidisciplinary approach). Their aim is to remind the limitations of antibiotic prophylaxis and to insist on hospital hygiene measures. Future challenges will be to obtain a better understanding of the mechanisms associated with the contamination of the valve and to optimize the adaptation of the current epidemiological prophylaxis. In this first part, we will describe the preventive and diagnostic approaches of infective endocarditis.

Left ventricular regional function and maximal exercise capacity in aortic stenosis

AIMS

The objective assessment of maximal exercise capacity (MEC) using peak oxygen consumption (VO2) measurement may be helpful in the management of asymptomatic aortic stenosis (AS) patients. However, the relationship between left ventricular (LV) function and MEC has been relatively unexplored. We aimed to identify which echocardiographic parameters of LV systolic function can predict MEC in asymptomatic AS.

METHODS AND RESULTS

Asymptomatic patients with moderate to severe AS (n = 44, aortic valve area <1.5 cm(2), 66 ± 13 years, 75% of men) and preserved LV ejection fraction (LVEF > 50%) were prospectively referred for resting echocardiography and cardiopulmonary exercise test. LV longitudinal strain (LS) of each myocardial segment was measured by speckle tracking echocardiography (STE) from the apical (aLS) 4-, 2-, and 3-chamber views. An average value of the LS of the analysable segments was provided for each myocardial region: basal (bLS), mid (mLS), and aLS. LV circumferential and radial strains were measured from short-axis views. Peak VO2 was 20.1 ± 5.8 mL/kg/min (median 20.7 mL/kg/min; range 7.2-32.3 mL/kg/min). According to the median of peak VO2, patients with reduced MEC were significantly older (P < 0.001) and more frequently females (P = 0.05). There were significant correlations between peak VO2 and age (r = -0.44), LV end-diastolic volume (r = 0.35), LV stroke volume (r = 0.37), indexed stroke volume (r = 0.32), and E/e' ratio (r = -0.37, all P < 0.04). Parameters of AS severity and LVEF did not correlate with peak VO2 (P = NS for all). Among LV deformation parameters, bLS and mLS were significantly associated with peakVO2 (r = 0.43, P = 0.005, and r = 0.32, P = 0.04, respectively). With multivariable analysis, female gender (β = 4.9; P = 0.008) and bLS (β = 0.50; P = 0.03) were the only independent determinants (r(2) = 0.423) of peak VO2.

CONCLUSION

In asymptomatic AS, impaired LV myocardial longitudinal function determines reduced MEC. Basal LS was the only parameter of LV regional function independently associated with MEC.

[Asymptomatic severe aortic stenosis with preserved left ventricular ejection fraction. Evaluation by exercise test: which results and which decision?]

Aortic stenosis is the most common valvular heart disease in Europe and North America and it is a real public health problem. Its prevalence increases with population aging. Symptomatic patients require surgery (class I, level of evidence B). In asymptomatic patients, a stress test with or without imaging is recommended to unmask the false asymptomatic patients and refine risk stratification of occurrence of major events. This support remains difficult and makes the optimal timing for surgery controversial in the absence of prospective data on the determinants of aortic stenosis progression, multicenter studies on risk stratification or randomized studies on patient management. The complexity of care arises from the balance between the spontaneous disease risk (risk of sudden death and irreversible left ventricular dysfunction) and the risk of surgery and prosthetic complications. It is therefore crucial to identify subgroups of patients at risk of pejorative progression in whom prophylactic surgery may be considered. This article focuses on evaluating during exercise asymptomatic patients with severe aortic stenosis and preserved left ventricular ejection fraction. We will explain how to perform the test, determine which echocardiographic measurements should be obtained, focusing on the diagnostic and prognostic value of these measurements and discuss indications for surgery according to new practice guidelines.

[Left ventricular contractile reserve in asymptomatic patients with primary mitral regurgitation]

This study aimed to quantify left ventricular contractile reserve (LVCR) and to evaluate its usefulness for risk stratification in asymptomatic patients with primary mitral regurgitation (MR). Resting and exercise echocardiography including two-dimensional speckle tracking was performed in 115 consecutive asymptomatic patients with moderate to severe primary MR. LCVR was defined as an exercise-induced increase in LV ejection fraction ≥ 4% or in LV global longitudinal strain ≥ 2%. LVCR was absent in approximately one half of the population. This absence was a strong independent predictor of cardiac events when assessed by exercise-induced changes in LV longitudinal function, but not when measured by exercise-induced changes in LV ejection fraction.

Impact of global hemodynamic load on exercise capacity in aortic stenosis

BACKGROUND

The determinants of maximal exercise capacity (MEC) in aortic stenosis (AS) are, in large part, unknown. We hypothesized that the left ventricular (LV) global hemodynamic load--as assessed by the valvulo-arterial impedance (Zva)--is one of the main determinants of MEC and we sought to evaluate the factors associated with reduced MEC in AS.

METHOD AND RESULTS

Asymptomatic patients with moderate or severe AS (n=62, aortic valve area <1.5 cm(2), 65 ± 13 years, 68% men) and preserved LV systolic function (ejection fraction>50%) were prospectively referred for comprehensive resting echocardiography and cardiopulmonary exercise test. Absolute peak VO2 was 19.5 ± 5.7 mL/kg/min (median 19.6 mL/kg/min; range 7.2-33.1 mL/kg/min). There were significant correlations between peak VO2 and: age, body mass index, LV stroke volumes, cardiac output, mean flow rate, mitral annulus s' and e' wave velocities, E/e' ratio and left atrial diameter (all p<0.05). Indexed mean flow rate and Zva were the strongest univariable echocardiographic determinants of peak VO2 (r=0.44, p<0.001 and r=-0.39, p=0.002, respectively). In addition, patients with reduced MEC (peak VO2<median) had higher Zva than those with preserved MEC (4.24 ± 1.18 vs. 3.71 ± 0.68 mmHg/mL/m(2), p=0.036). In multivariable analysis, age (p<0.001) and Zva (p=0.048) were the only independent predictors (r(2)=0.40) of peak VO2.

CONCLUSION

In asymptomatic patients with moderate to severe AS, MEC varies widely among patients, and is often lower than expected. Global LV hemodynamic load is the main echocardiographic determinant of reduced MEC in these patients, suggesting its usefulness for their clinical evaluation and management.