[Fetal aortic valvuloplasty in critical aortic stenosis: indication, technique and postnatal outcomes]

Aortic stenosis is a complex heart disease that involves the aortic valve and the left ventricle. Impairment of the left ventricle, abnormalities in its size, systolic and diastolic function determine the postnatal outcomes in the same way as the aortic valve. In the most severe forms, the left ventricle cannot provide systemic circulation at birth and the physiology is that of hypoplastic left heart syndrome. Fetal aortic valvuloplasty has been developed in the 90s to prevent in utero progression of aortic stenosis to hypoplastic left heart syndrome. In the present article, the most recently reported data about indications, procedure details and postnatal outcomes were reviewed.

Feasibility and safety of transfemoral transcatheter aortic valve implantation performed with a percutaneous coronary intervention-like approach

BACKGROUND

Transfemoral percutaneous transcatheter aortic valve implantation (TF-TAVI) is a safe, reproducible and established procedure, mainly performed under local anaesthesia, which is mostly administered and monitored by a dedicated anaesthesia team (regular approach). Our centre has developed a standardized pathway of care, and eligible patients are selected for a minimalist TF-TAVI, entirely managed by operators without the presence of the anaesthesia team in the operating room, like most interventional coronary procedures ("percutaneous coronary intervention-like" approach [PCI approach]).

AIM

To compare the safety and efficacy of TF-TAVI performed with the PCI approach versus the regular approach.

METHODS

The analysis population comprised all patients who underwent TF-TAVI with the PCI or regular approach in our institution from November 2016 to July 2019. The two co-primary endpoints were early safety composite and early efficacy composite at 30days as defined by the Valve Academic Research Consortium-2. The PCI (n=137) and Regular (n=221) approaches were compared using the propensity score based method of inverse probability of treatment weighting.

RESULTS

No differences were observed after comparison of TAVI performed with the PCI or regular approach regarding the composite safety endpoint (7.3% vs. 11.3%; odds ratio 0.63, 95% confidence interval 0.37 to 1.07; P=0.086) or the composite efficacy endpoint (4.4% vs. 6.3%; odds ratio 0.78, 95% confidence interval 0.41 to 1.49; P=0.45).

CONCLUSIONS

This study suggests that the efficacy and safety of TF-TAVI entirely managed by a PCI approach for selected patients are not different to those when TF-TAVI is performed with the attendance of a full anaesthesia care team. The PCI approach appears to be a safe and efficient clinical pathway, providing an appropriate and rational utilization of anaesthesiology resources, and could be used for the majority of TF-TAVI procedures.

Non-contrast myocardial T1 global and regional reference values at 3 Tesla cardiac magnetic resonance in aortic stenosis

BACKGROUND

T1 mapping using cardiac magnetic resonance (CMR) was recently proposed as a promising non-contrast imaging technique for the assessment of diffuse myocardial fibrosis (MF) in aortic stenosis (AS).

AIMS

To provide reference values for native T1 mapping at 3 Tesla magnetic field strength in subjects with moderate or severe AS and in control subjects; to identify factors associated with the presence of diffuse MF in severe AS; to assess the regional distribution of diffuse MF; and to compare the level of diffuse MF in the different types of AS, stratified by flow and gradient patterns.

METHODS

Retrospective study based on 160 consecutive patients with moderate (n=11) to severe (n=149) AS and 47 control subjects referred for CMR.

RESULTS

Mean native T1 increased progressively across controls (1221±23ms), moderate AS (1249±26ms) and severe AS (1273±43ms). T1 times correlated significantly with left ventricular (LV) remodelling (indexed LV mass and LV diastolic volume) and functional LV alterations (global longitudinal strain and LV ejection fraction). Native T1 appears to be elevated in the basal segments of the septum in moderate AS, and to extend to midventricular and apical segments in severe AS. Mean T1 time was higher in classical low-flow/low-gradient AS (1295±62ms) than in the other types of AS (P=0.006). The level of diffuse MF in paradoxical low-flow/low-gradient AS (1280±42ms) was higher than in moderate AS, but similar to that in high-gradient AS (1271±42ms) (P=0.07).

CONCLUSIONS

Assessment of diffuse MF in AS using T1 mapping is feasible and reproducible in clinical practice. T1 value increases with AS severity, along with morphological and functional LV alterations, particularly in the basal segments of the septum.

Prosthesis-patient mismatch is an independent predictor of congestive heart failure after transcatheter aortic valve replacement

BACKGROUND

Little is known about the effect of prosthesis-patient mismatch (PPM) on outcomes after transcatheter aortic valve replacement. We reported previously an increased risk of PPM with the SAPIEN 3 transcatheter heart valve (S3-THV).

AIMS

To investigate the association of PPM with 1-year outcomes in patients with severe aortic stenosis (AS) implanted with S3-THV.

METHODS

Moderate PPM was defined by an indexed effective orifice area (iEOA)≤0.85cm²/m², and severe PPM by an iEOA<0.65cm²/m². Inclusion criteria were severe symptomatic AS and implantation with S3-THV. The primary endpoint was hospitalization for congestive heart failure (CHF) at 1 year; the secondary endpoint was all-cause mortality.

RESULTS

A total of 208 consecutive patients were included between 2016 and 2018. Male sex was prevalent (53.8%), mean age was 81.9±6.2 years, mean EuroSCORE II was 4.35±3.37, mean LVEF was 57.9±13%. Moderate and severe PPM were observed in 69 (33.2%) and 10 (4.8%) patients. Patients with PPM were younger (80.4±7 vs 82.8±5.41 years; P=0.006), had a larger BSA (1.84±0.19 vs 1.77±0.19 m²; P=0.01), a lower iEOA (0.73±0.08 vs 1.11±0.22 cm²/m²; P<0.001) and a higher mean gradient (14±4.6 vs 11.9±3.9mmHg; P<0.001). CHF occurred in 16.5% vs 7% (P=0.03). By multivariable analysis, PPM was independently associated with CHF (hazard ratio [HR] 3.17, 95% confidence interval [CI] 1.17 to 8.55; P=0.032), especially in patients with mitral regurgitation≥2/4 (HR>100, 95%CI>100 to>1000; P<0.01). PPM did not correlate with all-cause mortality (HR 0.90, 95%CI 0.22 to 3.03; P=0.86).

CONCLUSIONS

PPM after S3-THV implantation is strongly associated with CHF at 1 year, but is not correlated with overall mortality.

[Prenatal path of care following the diagnosis of a malformation for which a novel prenatal therapy is available]

OBJECTIVES

Fetal therapy is part of the available care offer for several severe malformations. The place of these emergent prenatal interventions in the prenatal path of care is poorly known. The objective of this study is to describe the decision-making process of patients facing the option of an emergent in utero intervention.

METHODS

We have conducted a retrospective monocentric descriptive study in the department of maternal-fetal medicine of Necker Hospital. We collected data regarding eligibility or not for fetal surgery and the pregnancy outcomes of patients referred for myelomeningocele, diaphragmatic hernia, aortic stenosis and low obstructive uropathies.

RESULTS

All indications combined, 70% of patients opted for fetal surgery. This rate was lower in the case of myelomeningocele with 21% consent, than in the other pathologies: 69% for diaphragmatic hernias, 90% for aortic stenoses and 76% for uropathy. When fetal intervention was declined, the vast majority of patients opted for termination of pregnancy: 86%. In 14% of the considering fetal surgery, the patient was referred too far.

CONCLUSION

The acceptance rate for fetal surgeries depends on condition. It offers an additional option and is an alternative for couples for which termination of pregnancy (TOP) is not an option. Timely referral to an expert center allows to discuss the place of a fetal intervention and not to deprive couples of this possibility.

[Infection and TAVI]

Since trans-catheter valve implantation (TAVI) has emerged for severe symptomatic aortic stenosis treatment, infective endocarditis (IE) appears as a rare but severe complication. Like surgical aortic valve remplacement infective endocarditis (SAVR-IE), TAVI-IE has a noxious impact on morbidity and mortality. Compared to SAVR-IE, TAVI-IE present some similarities as well as differences. Most TAVI-IE occurred during the first year and enterococcus is the more common pathogen. A multimodality imaging approach including echocardiography, multislice computed tomography (CT) and positron emission tomography-CT with blood culture is necessary for the diagnosis. In this high-risk population, the vast majority of TAVI-IE patients are treated with antibiotic therapy alone. Consequently to the expanded indication, the increasing number of TAVI-IE will appear more frequently. If initially only few clinical cases of IE were reported, sparse observational multicenter registries have now been published. Relevant differences were noted on these registries, but some recent publications have provided new informations on IE. The present review reports incidence, symptoms, microbiological profil, risk factors and clinicals outcomes of TAVI-IE. Eventually, we describe the management and the treatment of IE in the context of TAVI.

Fetal cardiac interventions: Where do we stand?

Fetal cardiac intervention (FCI) is a novel and evolving technique that allows for in utero treatment of a subset of congenital heart disease. This review describes the rationale, selection criteria, technical features, and current outcomes for the three most commonly performed FCI: fetal aortic stenosis with evolving hypoplastic left heart syndrome (HLHS); HLHS with intact or restrictive atrial septum; and pulmonary atresia with intact ventricular septum, with concern for worsening right ventricular (RV) hypoplasia.

[Management of non-rhythmic complications of TAVI procedures]

Transcatheter aortic valve (TAVI) is the treatment of choice in patients with severe symptomatic aortic stenosis at high surgical risk. Recent data have also shown favorable results in patients considered to have an intermediate operative risk, which broadens the application of this new technology. Despite its success, the TAVI procedure has been associated with life-threatening complications. Advances in preoperative screening and patient selection have reduced the incidence of these complications. When these complications occur, early recognition and rapid management are essential. The purpose of this review is to describe non-rhythmic mechanical complications attributable to TAVI procedures with their predictive factors, how to prevent and manage them.

[Transcatheter aortic valve implantation and conduction disturbances]

Transcatheter aortic valve implantation (TAVI) is currently becoming the treatment of choice for patients with calcific aortic stenosis. Despite several technical improvements, the incidence of conduction disturbances has not diminished and remains TAVI's major complication. These disturbances include the occurrence of left bundle branch block and/or high-grade atrioventricular block often requiring pacemaker implantation. The proximity of the aortic valve to the conduction system (conduction pathways) accounts for the occurrence of these complications. Several factors have been identified as carrying a high risk of conduction disturbances like the presence of pre-existing right bundle branch block, the type of valve implanted, the volume of aortic and mitral calcifications, the size of the annulus and the depth of valve implantation. Left bundle branch block is the most frequent post TAVI conduction disturbance. Whereas the therapeutic strategy for persistent complete atrioventricular block is simple, it becomes complex in the presence of fluctuating changes in PR interval and left bundle branch block duration. The QRS width threshold value (150-160 ms) indicative of the need for pacemaker implantation is still being debated. Although there are currently no recommendations regarding the management of these conduction disturbances, the extension of TAVI indications to patient at low surgical risk calls for a standardization of our practice. However, a decision algorithm was recently proposed by a group of experts composed of interventional cardiologists, electrophysiologists and cardiac surgeons. There are still uncertainties about the appropriate timing of pacemaker implantation and the management of new onset left bundle branch block.

Why should we extend transcatheter aortic valve implantation to low-risk patients? A comprehensive review

Within the past decade, transcatheter aortic valve implantation (TAVI) has become established as the optimal treatment option for elderly, inoperable and high-risk patients with severe aortic stenosis, and is now recommended by international guidelines. Randomized controlled trials have demonstrated the non-inferiority of TAVI to open surgery in intermediate-risk patients and, most recently, in low-risk patients. Further randomized controlled trials are underway, but existing studies have already provided reassuring data in this cohort, and TAVI is offered routinely to younger and lower-risk patients in numerous centers. Improvements in the design of devices and delivery systems, accompanied by increased operator experience, have dramatically improved the safety of the procedure, and further expansion into low-risk groups seems inevitable once concerns about valve durability and device cost have been addressed. In this article, we provide a review of the existing literature, and estimate the clinical impact of TAVI in low-risk patients. Abbreviated title: Why should we extend TAVI to low-risk patients?

Position paper of French Interventional Group (GACI) for TAVI in France in 2018

Aortic stenosis is a frequent disease in the elderly. Its prevalence is 0.4% with a sharp increase after the age of 65, and its outcome is very poor when the patient becomes symptomatic. The interventional procedure known as TAVI (trans-catheter aortic valve implantation), which was developed in France and carried out for the first time in Rouen by Prof. Alain Cribier and his team in 2002, has proven to be a valid alternative to surgical aortic valve replacement. At first, this technique was shown to be efficient in patients with contra-indications to surgical treatment or deemed to be at high surgical risk. Given the very promising outcomes achieved as a result of close heart team collaboration, appropriate patient selection, simplified procedures and reduced complication rates, transfemoral (TF) TAVI is now preferred in symptomatic intermediate risk patients>75 years old according to the latest ESC guidelines. In 2017, in France, TAVI is currently performed in 50 centers with on-site cardiac surgery. The 2016 TAVI outcomes recorded in the French national TAVI registry (France TAVI) are very encouraging and show that for 7133 patients treated (age 83.4±7 years, logistic Euroscore 14%), 87% of whom via the TF approach, cross-over to surgery was very low (0.5%) with a 3.0% in-hospital mortality rate. The substantial increase in TAVI indications and the improvement of its outcomes may in the near future call for a reconsideration of the number of high volume centers authorized to carry out this technique.

Transcutaneous aortic valve implantation using the carotid artery access: Feasibility and clinical outcomes

BACKGROUND

Transcarotid access is an alternative route for transcutaneous aortic valve implantation (TAVI) in patients with impossible transfemoral access.

AIMS

We evaluated the safety, effectiveness and early and late clinical outcomes of CoreValve^® implantation via the common carotid artery.

METHODS

Eighteen patients (10 men, 8 women; mean age 84±5 years) at high surgical risk (mean EuroSCORE II 16±13%) with significant peripheral artery disease underwent TAVI via common carotid artery access under general anaesthesia. Mean aortic valve area was 0.64±0.13cm² (0.36±0.07cm²/m²).

RESULTS

At a mean follow-up of 605±352 days, two patients (11%) had died in hospital, on days 6 and 20, as a result of sepsis with multiorgan failure (n=1) or pneumonia (n=1). There were no perioperative deaths, myocardial infarctions or strokes. Perioperative prosthesis embolization occurred in one patient (6%), requiring implantation of a second valve. In-hospital complications occurred in four patients (23%): blood transfusion for transient significant bleeding at the access site in one patient (6%); permanent pacemaker implantation in two patients (11%); and pericardial drainage in one patient (6%). The rate of event-free in-hospital stay was 66%. Post-procedural echocardiography showed very good haemodynamic performance, with a mean gradient of 8±3mmHg. Moderate paravalvular leak was present in one patient (6%). Mean intensive care unit stay was 48±31h; mean in-hospital stay was 7±3 days.

CONCLUSION

TAVI performed by transcarotid access in this small series of severely ill patients was associated with a low incidence of complications, which were associated with the procedure itself rather than the access route.

Usefulness of 3-Tesla cardiac magnetic resonance imaging in the assessment of aortic stenosis severity in routine clinical practice

BACKGROUND

Recently, 1.5-Tesla cardiac magnetic resonance imaging (CMR) was reported to provide a reliable alternative to transthoracic echocardiography (TTE) for the quantification of aortic stenosis (AS) severity. Few data are available using higher magnetic field strength MRI systems in this context.

AIMS

To evaluate the feasibility and reproducibility of the assessment of aortic valve area (AVA) using 3-Tesla CMR in routine clinical practice, and to assess concordance between TTE and CMR for the estimation of AS severity.

METHODS

Ninety-one consecutive patients (60 men; mean age 74±10years) with known AS documented by TTE were included prospectively in the study.

RESULTS

All patients underwent comprehensive TTE and CMR examination, including AVA estimation using the TTE continuity equation (0.81±0.18cm²), direct CMR planimetry (CMRp) (0.90±0.22cm²) and CMR using Hakki's formula (CMRhk), a simplified Gorlin formula (0.70±0.19cm²). Although significant agreement with TTE was found for CMRp (r=0.72) and CMRhk (r=0.66), CMRp slightly overestimated (bias=0.11±0.18cm²) and CMRhk slightly underestimated (bias=-0.11±0.17cm²) AVA compared with TTE. Inter- and intraobserver reproducibilities of CMR measurements were excellent (r=0.72 and r=0.74 for CMRp and r=0.88 and r=0.92 for peak aortic velocity, respectively).

CONCLUSION

3-Tesla CMR is a feasible, radiation-free, reproducible imaging modality for the estimation of severity of AS in routine practice, knowing that CMRp tends to overestimate AVA and CMRhk to underestimate AVA compared with TTE.

[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.

[Anaesthetic management of patients with bicuspid aortic valve for delivery. About two consecutive cases]

Cardiac diseases are the second cause of non-obstetrical death during pregnancy in France. Bicuspid aortic valve is the most frequent congenital cardiac disease but its characteristics are little known. We report two consecutive cases of pregnant patients with aortic bicuspidy, one with a severe aortic stenosis and one with a severe dilatation of the ascending aorta. We describe the anaesthetic management of delivery for these two cases and summarize the current recommendations for management of this condition during pregnancy.