Predictors of Long-Term Outcome of Isolated Surgical Aortic Valve Replacement in Aortic Regurgitation With Reduced Left Ventricular Ejection Fraction and Extreme Left Ventricular Dilatation

Left Ventricular Reverse Remodeling after Surgical Aortic Valve Replacement for Aortic Regurgitation-An Explorative Study

BACKGROUND

The timing of treatment for chronic aortic valve regurgitation (AR), especially in asymptomatic patients, is gaining attention since less invasive strategies have become available. The aim of the present study was to evaluate left ventricular reverse remodeling after aortic valve replacement (AVR) for severe AR.

METHODS

Patients (n = 25) who underwent surgical AVR for severe AR with left ventricular ejection fraction (LVEF) less than 55% were included in this study. Preprocedural and follow-up clinical and echocardiographic measurements of LVEF and left ventricular (LV) diameters were retrospectively analyzed.

RESULTS

Mean LVEF increased significantly following surgical AVR (p < 0.0001). LV diameters showed a clear regression (p = 0.0088). Younger patients and those receiving a mechanical valve tended to have less improved LVEF on follow-up than patients over 60 years or the ones who were implanted with a biological prosthesis (p = 0.0239 and p = 0.069, respectively). Gender had no effect on the degree of LVEF improvement (p = 0.4908).

CONCLUSIONS

We demonstrated significant LV reverse remodeling following AVR for AR. However, more data are needed on LV functional and geometrical improvement comparing the different types of valve prostheses to provide an optimal treatment strategy.

Aortic Regurgitation: From Valvular to Myocardial Dysfunction

Chronic aortic regurgitation (AR) leads to volume overload in the left ventricle (LV), which is well tolerated for years. In this condition, the LV usually dilates with minimal reduction in the ejection fraction (EF), even in the absence of symptoms. Echocardiography is the primary imaging test used to quantify AR. However, no single assessment of Doppler measures is accurate and precise in individual patients; therefore, the integration of multiple parameters is necessary. Recent guidelines recommend surgical treatment for severe AR in patients who are symptomatic or have an LVEF < 55% and an end-systolic diameter > 50 mm. Nevertheless, advances in imaging technology have improved the quantification of AR and the assessment of LV subclinical dysfunction. It is widely recognized that patients who undergo aortic valve replacement/repair (AVR) due to symptoms or a low LVEF experience worse outcomes than those undergoing AVR for non-Class I indications. In fact, subclinical irreversible myocardial damage may occur in clinically well-compensated and closely monitored patients while awaiting formal surgical indications. This condition could be prevented by the use of multimodal imaging parameters, in particular longitudinal LV strain and magnetic resonance imaging. In addition, better cut-off values for mortality predictors should be established. This review aims to identify simple models that integrate several echocardiographic and cardiac magnetic resonance-derived parameters to predict the optimal timing of surgical treatment in asymptomatic patients with chronic severe AR.

Echocardiographic assessment of aortic regurgitation: a narrative review

Aortic regurgitation (AR) is the third most frequently encountered valve lesion and may be caused by abnormalities of the valve cusps or the aorta. Echocardiography is instrumental in the assessment of AR as it enables the delineation of valvular morphology, the mechanism of the lesion and the grading of severity. Severe AR has a major impact on the myocardium and carries a significant risk of morbidity and mortality if left untreated. Established and novel echocardiographic methods, such as global longitudinal strain and three-dimensional echocardiography, allow an estimation of this risk and provide invaluable information for patient management and prognosis. This narrative review summarises the epidemiology of AR, reviews current practices and recommendations with regards to the echocardiographic assessment of AR and outlines novel echocardiographic tools that may prove beneficial in patient assessment and management.

A heart valve dedicated for aortic regurgitation: Review of technology and early clinical experience with the transfemoral Trilogy system

Aortic regurgitation (AR) is associated with morbidity and premature mortality. Surgical aortic valve replacement is not an option for many patients due to an adverse surgical risk profile, whilst transcatheter aortic valve implantation with most available prostheses has demonstrated suboptimal implantation success and outcomes. The JenaValve Trilogy™ system provides an attractive solution for such patients as it utilizes clips that directly attach onto the native valve leaflets to anchor. Initially designed for transapical delivery, the current transfemoral delivery system is under investigation in the United States and approved for aortic stenosis and regurgitation in Europe. We present an expert review on the technical aspects of the Trilogy system, provide a guide for implantation, discuss the available evidence for the technology and provide illustrative case examples.

Left ventricle reverse remodeling in chronic aortic regurgitation patients with dilated ventricle after aortic valve replacement

BACKGROUND

Aortic valve replacement (AVR) for chronic aortic regurgitation (AR) with a severe dilated left ventricle and dysfunction leads to left ventricle remodeling. But there are rarely reports on the left ventricle reverse remodeling (LVRR) after AVR. This study aimed to investigate the LVRR and outcomes in chronic AR patients with severe dilated left ventricle and dysfunction after AVR.

METHODS

We retrospectively analyzed the clinical datum of chronic aortic regurgitation patients who underwent isolated AVR. The LVRR was defined as an increase in left ventricular ejection fraction (LVEF) at least 10 points or a follow-up LVEF ≥ 50%, and a decrease in the indexed left ventricular end-diastolic diameter of at least 10%, or an indexed left ventricular end-diastolic diameter ≤ 33 mm/m². The changes in echocardiographic parameters after AVR, survival analysis, the predictors of major adverse cardiac events (MACE), the association between LVRR and MACE were analyzed.

RESULTS

Sixty-nine patients with severe dilated left ventricle and dysfunction underwent isolated AVR. LV remodeling in 54 patients and no LV remodeling in 15 patients at 6-12 months follow-up. The preoperative left ventricular dimensions and volumes were larger, and the EF was lower in the LV no remodeling group than those in the LV remodeling group (all p < 0.05). The adverse LVRR was the predictor for MACE at follow-up. The mean follow-up period was 47.29 months (range 6 to 173 months). The rate of freedom from MACE was 94.44% at 5 years and 92.59% at 10 years in the remodeling group, 60% at 5 years, and 46.67% at 10 years in the no remodeling group.

CONCLUSIONS

The left ventricle remodeling after AVR was the important predictor for MACE. LV no remodeling may not be associated with benefits from AVR for chronic aortic regurgitation patients with severe dilated LV and dysfunction.

Transcatheter aortic valve replacement for aortic regurgitation in Asians: TAVR for aortic regurgitation in Asians

AIMS

Although surgical aortic valve replacement (SAVR) is currently the recommended intervention for patients with native AR without aortic stenosis, a significant proportion of Asian patients undergo transcatheter aortic valve replacement (TAVR), which has not been studied fully for safety and outcomes. This systematic review aims to examine the characteristics and outcomes of Asian patients with pure native aortic regurgitation (AR) undergoing TAVR.

METHODS AND RESULTS

PubMed, Embase, Scopus, Web of Science and Cochrane CENTRAL were systematically searched for randomised controlled trials, observational studies and case reports published  from inception to 2 April 2020, involving patients of Asian ethnicity with pure native aortic regurgitation who had undergone TAVR. Our primary outcome was all-cause mortality, with secondary outcomes including all major complications. Five studies (n=274 patients) and eight case reports were included. Device success was reported in 94.9% of the patients, the all-cause mortality rate was 4.4%, 2.5% were converted to SAVR, 1.7% had post-operative paravalvular leak and 6.7% required permanent pacemaker implantation.

CONCLUSIONS

TAVR has demonstrated acceptable safety and efficacy in Asian patients with pure AR displaying low mortality rates and few adverse outcomes.