Long-term outcome of congenital aortic valve stenosis : predictors of reintervention

Objectif Evaluer l'évolution à long-terme d'une population de patients pédiatriques souffrant de sténose aortique congénitale et ayant subi une intervention chirurgicale sur cette valve, et déterminer les facteurs de risques associés à une ré-intervention. Patients et méthode De 1985 à 2009, 77 patients, en moyenne âgés de 5.8 ± 5-6 ans, ont été suivis dans notre Service durant 14.8 ± 9-1 années. Résultats La première intervention montre d'excellents résultats avec 86% des patients ayant un gradient aortique résiduel < 50 mmHg et seulement 7% avec une nouvelle fuite aortique >1. La survie à long terme est de 91% A 25 ans. A un intervalle de 7.6 ± 5-3 ans, 30 patients 011t nécessité une ré-intervention (39%), principalement à cause d'une récidive de la sténose aortique. Le pourcentage de patients libre de ré¬intervention était de 97, 89, 75, 53, and 42% à respectivement 1, 10,15, 20, et 25 ans. Les facteurs de risques cle ré-interventions étaient le gradient aortique residuel plus élevé (p=0.00 01), la fuite aortique post-intervention >1 (p=0.02), la valvuloplasty au ballon préalable (p-0.04) et l'épaisseur augmentée de la paroi postérieure du ventricule gauche (p=o.i). Conclusions L'intervention chirurgicale sur la valve aortique est un procédé sûr et efficace pour les sténoses aortiques congénitales et démontre d'excellents résultats au niveau de la survie. Cependant le taux de ré-intervention est élevé et influencé par le gradient aortique résiduel plus élevé, la fuite aortique post-intervention >1, la valvuloplasty au ballon préalable et l'épaisseur augmentée de la paroi postérieure du ventricule gauche. L'étude démontre qu'un suivi à long-terme est recommandé pour ces patients.

Valved stents for transapical pulmonary valve replacement.

OBJECTIVES: Pulmonary valve insufficiency remains a leading cause for reoperations in congenital cardiac surgery. The current percutaneous approach is limited by the size of the access vessel and variable right ventricular outflow tract morphology. This study assesses the feasibility of transapical pulmonary valve replacement based on a new valved stent construction concept. METHODS: A new valved stent design was implanted off-pump under continuous intracardiac echocardiographic and fluoroscopic guidance into the native right ventricular outflow tract in 8 pigs (48.5 +/- 6.0 kg) through the right ventricular apex, and device function was studied by using invasive and noninvasive measures. RESULTS: Procedural success was 100% at the first attempt. Procedural time was 75 +/- 15 minutes. All devices were delivered at the target site with good acute valve function. No valved stents dislodged. No animal had significant regurgitation or paravalvular leaking on intracardiac echocardiographic analysis. All animals had a competent tricuspid valve and no signs of right ventricular dysfunction. The planimetric valve orifice was 2.85 +/- 0.32 cm(2). No damage to the pulmonary artery or structural defect of the valved stents was found at necropsy. CONCLUSIONS: This study confirms the feasibility of direct access valve replacement through the transapical procedure for replacement of the pulmonary valve, as well as validity of the new valved stent design concept. The transapical procedure is targeting a broader patient pool, including the very young and the adult patient. The device design might not be restricted to failing conduits only and could allow for implantation in a larger patient population, including those with native right ventricular outflow tract configurations.

Cardiac rotation and relaxation in patients with aortic valve stenosis.

BACKGROUND: Diastolic dysfunction with delayed relaxation and abnormal passive elastic properties has been described in patients with severe pressure overload hypertrophy. The purpose of this study was to evaluate the time course of rotational motion of the left ventricle in patients with aortic valve stenosis using myocardial tagging. METHODS: Myocardial tagging is a non-invasive method based on magnetic resonance which makes it possible to label ('tag') specific myocardial regions. From the motion of the tag's cardiac rotation, radial displacement and translational motion can be determined. In 12 controls and 13 patients with severe aortic valve stenosis systolic and diastolic wall motion was assessed in an apical and basal short axis plane. RESULTS: The normal left ventricle performs a systolic wringing motion around the ventricular long axis with clockwise rotation at the base (-4.4+/-1.6 degrees) and counter-clockwise rotation at the apex (+6.8+/-2.5 degrees) when viewed from the apex. During early diastole an untwisting motion can be observed which precedes diastolic filling. In patients with aortic valve stenosis systolic rotation is reduced at the base (-2.4+/-2.0 degrees; P<0.01) but increased at the apex (+12.0+/-6.0 degrees; P<0.05). Diastolic untwisting is delayed and prolonged with a decrease in normalized rotation velocity (-6.9+/-1.1 s(-1)) when compared to controls (-10.7+/-2.2 s(-1); P<0.001). Maximal systolic torsion is 8.0+/-2.1 degrees in controls and 14.1+/-6.4 degrees (P<0.01) in patients with aortic valve stenosis. CONCLUSIONS: Left ventricular pressure overload hypertrophy is associated with a reduction in basal and an increase in apical rotation resulting in increased torsion of the ventricle. Diastolic untwisting is delayed and prolonged. This may explain the occurrence of diastolic dysfunction in patients with severe pressure overload hypertrophy.

Clinical review: practical recommendations on the management of perioperative heart failure in cardiac surgery.

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.

La prothèse de St Jude medical chez les patients âges de plus de 65 ans [St Jude's Medical prosthesis in patients over 65].

Between September 1979 and December 1982, 56 St Jude Medical valvular prostheses were implanted in 54 patients over 65 years of age. Surgery consisted in simple aortic valve replacement (35 cases), simple mitral valve replacement (12 cases), double aortic and mitral valve replacement (2 cases), valve replacement and coronary artery bypass surgery (3 cases), aortic valve replacement and replacement of the ascending aorta (1 case) and mitral valve replacement and tricuspid annuloplasty (1 case). The operative mortality (within 30 days of surgery) was 3.5% (2 cases). Patients were assessed by clinical examination, ECG, chest X-ray, echocardiogram and laboratory investigations on average 19 months after surgery. There were 3 late deaths (1 endocarditis, 1 cardiac failure and 1 subdural haematoma). No cases of significant haemolysis were observed. There were no cases of thrombosis of the valve or any deaths directly related to the valve. Four patients had cerebral embolism (4.9% per patient/year). None were fatal and only 1 patient had sequellae. Clinical improvement was very significant; 96% of the patients are now in the NYHA Classes I and II whilst 80% were in Class III or IV before surgery. The cardiothoracic ratio decreased significantly from 0.56 to 0.51 (p less than 0.01). The authors conclude that elderly patients may derive great benefits from valvular cardiac surgery and that age in itself is not a contraindication to this type of surgery. The St Jude Medical prosthesis is an excellent prosthesis but thromboembolism remains a major problem as with other mechanical prostheses. Anticoagulation for life is essential.

The transventricular-transseptal access to the aortic root: a new route for extrapleural trans-catheter aortic stent-valve implantation.

Objective: The aim of this study was to investigate the feasibility of transventricular-transseptal approach (TVSA) for extrapleural transcatheter aortic valved stent implantation via a subxyphoidian access. Methods: In five porcine experiments (52.3 +/- 10.9 kg) the right ventricle was exposed via subxyphoidian access. Under the guidance of intracardiac echocardiography (ICE) and fluoroscopy, the transseptal access from right ventricle to left ventricle was created progressively by puncture and dilation with dilators (8F-26F). Valved stents built in-house from commercial tanned pericardium and self-expandable Nitinol stents were loaded into a cartridge. A delivery sheath was then introduced from the right ventricle into the left ventricle and then into the ascending aorta. The cartridge was connected and the valved stent was deployed in the aortic position. Then, the ventricular septal access was sealed with an Amplatzer septal occluder device and the right ventricular access was closed by tying prepared purse-string suture directly. Thirty minutes after the whole procedure, the animals were sacrificed for macroscopic evaluation of the position of valved stent and septal closure device. Result: Procedural success of TVSA was 100% at the first attempt. Mean procedure time was 49 +/- 4 min. Progressive dilatation of the transseptal access resulted in a measurable ventricular septal defect (VSD) after dilator sizes 18F and more. All valved stents were delivered at the target site over the native aortic valve with good acute valve function and no paravalvular leaks. During the procedure, premature beats (5/5) and supraventriclar tachycardias (5/5) were observed, but no atrial-ventricular block (0/5) occurred. Heart rate before (after) was 90 +/- 3 beats min(-1) (100 +/- 2 beats min(-1): p < 0.05), whereas blood pressure was 60 + 1 mm Hg (55 + 2 mm Hg (p < 0.05)). Total blood loss was 280 + 10 ml. The Amplatzer septal occluder devices were fully deployed and the ventricular septal accesses were sealed successfully, without detectable residual shunt. Conclusion: Trans-catheter implantation of aortic valved stent via extrapleural transventricular-transseptal access is technically feasible and has the potential for a simplified procedure under local anaesthesia. (C) 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B. V. All rights reserved.

Ascending aorta measurements as assessed by ECG-gated multi-detector computed tomography: a pilot study to establish normative values for transcatheter therapies

The aim of this study was to provide an insight into normative values of the ascending aorta in regards to novel endovascular procedures using ECG-gated multi-detector CT angiography. Seventy-seven adult patients without ascending aortic abnormalities were evaluated. Measurements at relevant levels of the aortic root and ascending aorta were obtained. Diameter variations of the ascending aorta during cardiac cycle were also considered. Mean diameters (mm) were as follows: LV outflow tract 20.3 +/- 3.4, coronary sinus 34.2 +/- 4.1, sino-tubular junction 29.7 +/- 3.4 and mid ascending aorta 32.7 +/- 3.8 with coefficients of variation (CV) ranging from 12 to 17%. Mean distances (mm) were: from the plane passing through the proximal insertions of the aortic valve cusps to the right brachio-cephalic artery (BCA) 92.6 +/- 11.8, from the plane passing through the proximal insertions of the aortic valve cusps to the proximal coronary ostium 12.1 +/- 3.7, and between both coronary ostia 7.2 +/- 3.1, minimal arc of the ascending aorta from left coronary ostium to right BCA 52.9 +/- 9.5, and the fibrous continuity between the aortic valve and the anterior leaflet of the mitral valve 14.6 +/- 3.3, CV 13-43%. Mean aortic valve area was 582.0 +/- 131.9 mm(2). The variation of the antero-posterior and transverse diameters of the ascending aorta during the cardiac cycle were 8.4% and 7.3%, respectively. Results showed large inter-individual variations in diameters and distances but with limited intra-individual variations during the cardiac cycle. A personalized approach for planning endovascular devices must be considered.

A new self-expanding aortic stent valve with annular fixation: in vitro haemodynamic assessment.

OBJECTIVE: Balloon-expandable stent valves require flow reduction during implantation (rapid pacing). The present study was designed to compare a self-expanding stent valve with annular fixation versus a balloon-expandable stent valve. METHODS: Implantation of a new self-expanding stent valve with annular fixation (Symetis, Lausanne, Switzerland) was assessed versus balloon-expandable stent valve, in a modified Dynatek Dalta pulse duplicator (sealed port access to the ventricle for transapical route simulation), interfaced with a computer for digital readout, carrying a 25 mm porcine aortic valve. The cardiovascular simulator was programmed to mimic an elderly woman with aortic stenosis: 120/85 mmHg aortic pressure, 60 strokes/min (66.5 ml), 35% systole (2.8 l/min). RESULTS: A total of 450 cardiac cycles was analysed. Stepwise expansion of the self-expanding stent valve with annular fixation (balloon-expandable stent valve) resulted in systolic ventricular increase from 120 to 121 mmHg (126 to 830+/-76 mmHg)*, and left ventricular outflow obstruction with mean transvalvular gradient of 11+/-1.5 mmHg (366+/-202 mmHg)*, systolic aortic pressure dropped distal to the valve from 121 to 64.5+/-2 mmHg (123 to 55+/-30 mmHg) N.S., and output collapsed to 1.9+/-0.06 l/min (0.71+/-0.37 l/min* (before complete obstruction)). No valve migration occurred in either group. (*=p<0.05). CONCLUSIONS: Implantation of this new self-expanding stent valve with annular fixation has little impact on haemodynamics and has the potential for working heart implantation in vivo. Flow reduction (rapid pacing) is not necessary.

In-hospital and 1-year mortality in patients undergoing early surgery for prosthetic valve endocarditis.

IMPORTANCE: There are limited prospective, controlled data evaluating survival in patients receiving early surgery vs medical therapy for prosthetic valve endocarditis (PVE). OBJECTIVE: To determine the in-hospital and 1-year mortality in patients with PVE who undergo valve replacement during index hospitalization compared with patients who receive medical therapy alone, after controlling for survival and treatment selection bias. DESIGN, SETTING, AND PARTICIPANTS: Participants were enrolled between June 2000 and December 2006 in the International Collaboration on Endocarditis-Prospective Cohort Study (ICE-PCS), a prospective, multinational, observational cohort of patients with infective endocarditis. Patients hospitalized with definite right- or left-sided PVE were included in the analysis. We evaluated the effect of treatment assignment on mortality, after adjusting for biases using a Cox proportional hazards model that included inverse probability of treatment weighting and surgery as a time-dependent covariate. The cohort was stratified by probability (propensity) for surgery, and outcomes were compared between the treatment groups within each stratum. INTERVENTIONS: Valve replacement during index hospitalization (early surgery) vs medical therapy. MAIN OUTCOMES AND MEASURES: In-hospital and 1-year mortality. RESULTS: Of the 1025 patients with PVE, 490 patients (47.8%) underwent early surgery and 535 individuals (52.2%) received medical therapy alone. Compared with medical therapy, early surgery was associated with lower in-hospital mortality in the unadjusted analysis and after controlling for treatment selection bias (in-hospital mortality: hazard ratio [HR], 0.44 [95% CI, 0.38-0.52] and lower 1-year mortality: HR, 0.57 [95% CI, 0.49-0.67]). The lower mortality associated with surgery did not persist after adjustment for survivor bias (in-hospital mortality: HR, 0.90 [95% CI, 0.76-1.07] and 1-year mortality: HR, 1.04 [95% CI, 0.89-1.23]). Subgroup analysis indicated a lower in-hospital mortality with early surgery in the highest surgical propensity quintile (21.2% vs 37.5%; P = .03). At 1-year follow-up, the reduced mortality with surgery was observed in the fourth (24.8% vs 42.9%; P = .007) and fifth (27.9% vs 50.0%; P = .007) quintiles of surgical propensity. CONCLUSIONS AND RELEVANCE: Prosthetic valve endocarditis remains associated with a high 1-year mortality rate. After adjustment for differences in clinical characteristics and survival bias, early valve replacement was not associated with lower mortality compared with medical therapy in the overall cohort. Further studies are needed to define the effect and timing of surgery in patients with PVE who have indications for surgery.

Aortic root morphology: a paradigm for successful reconstruction.

Aortic root (AoR) components provide synchronous and precise 3D deformation of the aortic root during the cardiac cycle in order to ensure closure and opening of the three leaflets over a lifetime. Any deviation from the natural 3D morphology, such as with AoR annulus dilatation, enlarged sinuses and/or dilatation of the sinotubular junction, as in the case of ascending aortic dilatation, may result in disruption of the natural AoR function. Surgical treatment of AoR pathology has two modalities: the replacement of the aortic valve by artificial prosthesis or by preservation of the three leaflets and reconstruction of the aortic root components. Currently, there are two basic aortic root reconstruction procedures: aortic root sparing and aortic valve reimplantation techniques. Regardless of the technique used, the restoration of adequate cusp coaptation, is from a technical point of view, the most important element to consider. To achieve this, there are two requirements that need to be met: (i) the valve coaptation should be superior to the level of the aortic root base by at least 8 mm and (ii) the coaptation height per se has to be ≥5 mm. Successful restoration of the aortic root requires adequate technical skills, detailed knowledge of aortic root anatomy and topography, and also knowledge of the spatial pattern of AoR elements. Recently, there has been growing interest in aortic root reconstructive procedures as well their modifications. As such, the aim of this review is to analyse aortic root topography and 3D anatomy from a surgical point of view. The review also focuses on potential risk regions that one should be aware of before the surgical journey into the 'deep waters area' of the AoR begins.