Aortic Stenosis: Guidelines and Evidence Gaps

Recent updates on asymptomatic and symptomatic aortic valve stenosis its diagnosis, pathogenesis, management and future perspectives

Aortic stenosis (AS) is very common in mid-aged and elderly patients, and it has been reported to have a negative impact on both short and long-term survival with a high mortality rate. The current study identified methods of diagnosis, incidence, and causes of AS, pathogenesis, intervention and management and future perspectives of Asymptomatic and Symptomatic Aortic stenosis. A systematic literature search was conducted using PubMed, Scopus and CINAHL, using the Mesh terms and key words "Aortic stenosis", "diagnostic criteria", "pathogenesis", "incidence and causes of AS" and" intervention and management strategies". Studies were retained for review after meeting strict inclusion criteria that included studies evaluating Asymptomatic and Symptomatic AS. Studies were excluded if duplicate publication, overlap of patients, subgroup studies of a main study, lack of data on AS severity, case reports and letters to editors. Forty-five articles were selected for inclusion. Incidence of AS across the studies ranged from 3 % to 7 %. Many factors have been associated with incidence and increased risk of AS, highest incidence of AS was described after aortic valve calcification, rheumatic heart disease, degenerative aortic valve disease, bicuspid aortic valve and other factors. AS is common and can be predicted by aortic root calcification volume, rheumatic heart disease, degenerative aortic valve disease, bicuspid aortic valve. Intervention and management for AS patients is a complex decision that takes into consideration multiple factors. On the other hand, there is not enough progress in preventive pharmacotherapy to slow the progression of AS.

Analysis of Prevalence and Clinical Features of Aortic Stenosis in Patients with and without Bicuspid Aortic Valve Using Machine Learning Methods

Aortic stenosis (AS) is the most commonly diagnosed valvular heart disease, and its prevalence increases with the aging of the general population. However, AS is often diagnosed at a severe stage, necessitating surgical treatment, due to its long asymptomatic period. The objective of this study was to analyze the frequency of AS in a population of cardiovascular patients using echocardiography (ECHO) and to identify clinical factors and features associated with these patient groups. We utilized machine learning methods to analyze 84,851 echocardiograms performed between 2010 and 2018 at the National Medical Research Center named after V.A. Almazov. The primary indications for ECHO were coronary artery disease (CAD) and hypertension (HP), accounting for 33.5% and 14.2% of the cases, respectively. The frequency of AS was found to be 13.26% among the patients (n = 11,252). Within our study, 1544 patients had a bicuspid aortic valve (BAV), while 83,316 patients had a tricuspid aortic valve (TAV). BAV patients were observed to be younger compared to TAV patients. AS was more prevalent in the BAV group (59%) compared to the TAV group (12%), with a p-value of <0.0001. By employing a machine learning algorithm, we randomly identified significant features present in AS patients, including age, hypertension (HP), aortic regurgitation (AR), ascending aortic dilatation (AscAD), and BAV. These findings could serve as additional indications for earlier observation and more frequent ECHO in specific patient groups for the earlier detection of developing AS.

Thirty-Day Readmission Rate & Healthcare Economic Effects of patients with Transcatheter Aortic Valve Replacement and Co-Existing Chronic Congestive Heart Failure

BACKGROUND

Transcatheter aortic valve replacement (TAVR) procedures have increased since adoption in 2010. Readmission for TAVR patients with underlying chronic congestive heart failure (cCHF) remains challenging. Therefore, we sought to determine the 30-day readmission rate (30-DRr) of patients who undergo TAVR & co-existing cCHF & its impact on mortality & healthcare utilization in the United States.

METHODS

We performed a retrospective study using the national readmission database year 2017 and 2018. The patients studied were discharged with TAVR as a principal diagnosis & underlying cCHF as a secondary diagnosis according to ICD-10 codes. The primary outcome was a 30-day readmission rate and mortality, while secondary outcomes were the most common diagnoses for readmission, & resource utilization.

RESULTS

A total of 76,892 index hospitalization for TAVR with co-existing cCHF: mean age was 79.7 years [SD: ± 2], & 54.5% of patients were males. In-hospital mortality rate for index admission was 1.63%. The 30-DRr was 9.5%. Among the group of readmitted patients, in-hospital mortality rate was 3.13%. Readmission mortality showed a statistically significant increase compared to index mortality (3.13% vs. 1.63%, adjusted p=<0.001, aOR: 2.1, 95% CI: 1.6-2.9). The total healthcare in-hospital economic spending was $94.4 million, and total patient charge of $412 million.

CONCLUSION

Approximately 1 in 10 patients who underwent TAVR with underlying cCHF had 30-DRr, with subsequent readmissions associated with increased healthcare spending. Readmission mortality showed a statistically significant increase when compared to index mortality. TAVR patients with cCHF are a vulnerable subset requiring additional outpatient care.

Soft robotic patient-specific hydrodynamic model of aortic stenosis and ventricular remodeling

Aortic stenosis (AS) affects about 1.5 million people in the United States and is associated with a 5-year survival rate of 20% if untreated. In these patients, aortic valve replacement is performed to restore adequate hemodynamics and alleviate symptoms. The development of next-generation prosthetic aortic valves seeks to provide enhanced hemodynamic performance, durability, and long-term safety, emphasizing the need for high-fidelity testing platforms for these devices. We propose a soft robotic model that recapitulates patient-specific hemodynamics of AS and secondary ventricular remodeling which we validated against clinical data. The model leverages 3D-printed replicas of each patient's cardiac anatomy and patient-specific soft robotic sleeves to recreate the patients' hemodynamics. An aortic sleeve allows mimicry of AS lesions due to degenerative or congenital disease, whereas a left ventricular sleeve recapitulates loss of ventricular compliance and diastolic dysfunction (DD) associated with AS. Through a combination of echocardiographic and catheterization techniques, this system is shown to recreate clinical metrics of AS with greater controllability compared with methods based on image-guided aortic root reconstruction and parameters of cardiac function that rigid systems fail to mimic physiologically. Last, we leverage this model to evaluate the hemodynamic benefit of transcatheter aortic valves in a subset of patients with diverse anatomies, etiologies, and disease states. Through the development of a high-fidelity model of AS and DD, this work demonstrates the use of soft robotics to recreate cardiovascular disease, with potential applications in device development, procedural planning, and outcome prediction in industrial and clinical settings.

Right ventricle to pulmonary artery coupling after transcatheter aortic valve implantation-Determinant factors and prognostic impact

Introduction

Right ventricular (RV) dysfunction and pulmonary hypertension (PH) have been previously associated with unfavorable outcomes in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI), but little is known about the effect of right ventricle (RV) to pulmonary artery (PA) coupling. Our study aimed to evaluate the determinant factors and the prognostic value of RV-PA coupling in patients undergoing TAVI.

Methods

One hundred sixty consecutive patients with severe AS were prospectively enrolled, between September 2018 and May 2020. They underwent a comprehensive echocardiogram before and 30 days after TAVI, including speckle tracking echocardiography (STE) for myocardial deformation analysis of the left ventricle (LV), left atrium (LA), and RV function. Complete data on myocardial deformation was available in 132 patients (76.6 ± 7.5 years, 52.5% men) who formed the final study population. The ratio of RV free wall longitudinal strain (RV-FWLS) to PA systolic pressure (PASP) was used as an estimate of RV-PA coupling. Patients were analyzed according to baseline RV-FWLS/PASP cut-off point, determined through time-dependent ROC curve analysis, as follows: normal RV-PA coupling group (RV-FWLS/PASP ≥0.63, n = 65) and impaired RV-PA coupling group (RV-FWLS/PASP < 0.63, n = 67).

Results

A significant improvement of RV-PA coupling was observed early after TAVI (0.75 ± 0.3 vs. 0.64 ± 0.3 before TAVI, p < 0.001), mainly due to PASP decrease (p < 0.001). LA global longitudinal strain (LA-GLS) is an independent predictor of RV-PA coupling impairment before and after TAVI (OR = 0.837, p < 0.001, OR = 0.848, p < 0.001, respectively), while RV diameter is an independent predictor of persistent RV-PA coupling impairment after TAVI (OR = 1.174, p = 0.002). Impaired RV-PA coupling was associated with a worse survival rate (66.3% vs. 94.9%, p-value < 0.001) and emerged as an independent predictor of mortality (HR = 5.97, CI = 1.44-24.8, p = 0.014) and of the composite endpoint of death and rehospitalization (HR = 4.14, CI = 1.37-12.5, p = 0.012).

Conclusion

Our results confirm that relief of aortic valve obstruction has beneficial effects on the baseline RV-PA coupling, and they occur early after TAVI. Despite significant improvement in LV, LA, and RV function after TAVI, RV-PA coupling remains impaired in some patients, it is mainly related to persistent pulmonary hypertension and is associated with adverse outcomes.

Ventricular strain patterns in multivalvular heart disease: a cross-sectional study

Multivalvular heart disease (MVD) is an aggregate of regurgitant and/or stenotic lesions of at least two cardiac valves. Ventricular tissue deformation imaging is a powerful predictor of subclinical myocardial dysfunction in patients with MVD.The aim of this study was to examine the left and right ventricular strain patterns in MVD as well as observe any association between right-sided valvular involvement (tricuspid or pulmonary valve lesion) with that of aortic and/or mitral valve lesion. Patients with at least moderate forms of MVD were included in the present study. 72 patients with mean age of 56.69 ± 14.59 years and various presentations of MVD were finally enrolled in this study. The commonest cause for MVD was rheumatic heart disease in these patients. Conventional 2-dimensional parameters as well as tissue deformation imaging parameters were assessed in offline mode for these patients. The Mean ± SD values for various quantitative 2D echocardiographic conventional and tissue deformation imaging were assessed. It was observed that LV strain parameters including the global longitudinal strain (GLS) were preserved whereas the RV strain parameters were mildly reduced (RV GLS total is - 19.49 ± 6.08%). Also, when conventional echocardiographic parameters were assessed to see any association between aortic and/or mitral valve disease with that of right-sided valvular lesions (tricuspid or pulmonary); 2D conventional echocardiographic parameters like left atrial dimension (p = 0.034), TAPSE (tricuspid annular plane systolic excursion) (p < 0.001), RVSP (right ventricular systolic pressure) (p < 0.001) and IVC (inferior vena cava) dimensions (p < 0.001) showed a statistically significant result; whereas, when strain parameters for LV and RV were assessed, they did not show any statistical difference for the same. In this series of patients with significant MVD, our findings suggest that ventricular strain parameters may be reliable markers of myocardial dysfunction, but may alter depending on the underlying combination of MVD, and right ventricular strain should also be an important parameter while assessing different combinations of MVD.

Stress echocardiogram in asymptomatic severe aortic stenosis

Aortic stenosis (AS) is one of the most common adult valve diseases. Therefore, current guidelines recommend prompt aortic valve intervention once symptoms occur. However, AS is predominantly a disease of the elderly, and these people may be underreporting their symptoms, have other comorbidities, or have a low level of exertion at the baseline or they might make a subconscious adjustment of their activities. Hence, stress testing can be a vital and objective tool to uncover their symptoms and prognosticate.

Post-operative Quality of Life after Full-sternotomy and Mini-sternotomy Aortic Valve Replacement

BACKGROUND

Few longitudinal data exist comparing quality of life (QoL) after full sternotomy aortic valve replacement (fsAVR) vs mini-sternotomy AVR (msAVR) METHODS: 1844 consecutive AVR prospectively enrolled in a European multicentre Registry were dichotomized according to surgical access. A non-parsimonious propensity-score matching selected 187 pairs of fsAVR or msAVR with comparable baseline characteristics. Hospital outcome was compared in the two groups. QoL was assessed with Short Form-36, further detailed in its Physical Component Score (PCS) and Mental Component Score (MCS). QoL was investigated at hospital admission, discharge, 1 month, 6 months and 1 year thereafter.

RESULTS

There were 1654 fsAVR and 190 msAVR in the entire population. fsAVR showed a worse preoperative risk-profile, a longer ICU length of stay (59.7 hours vs 38.8, p=0.002), and a higher life-threatening/disabling bleeding (4.1% vs. 0%; p=0.011); msAVR reported a higher early reintervention for failed index intervention (2.1% vs. 0.5%, p=0.001). QoL showed better PCS and MCS at 1 month after fsAVR, but no temporal-trend differences (PCS group-time p=0.202; MCS group-time p=0.141). Propensity-matched pairs showed comparable baseline characteristics and hospital outcome (p=NS for all endpoints), and comparable improvements of PCS and MCS over time, but no between-group differences over time (PCS group-time p=0.834; MCS group-time p=0.737).

CONCLUSIONS

Patients with similar baseline profiles report comparable hospital outcome and comparable improvement of physical and mental health, up to 1 year after surgery, with both fsAVR and msAVR. As for QoL, mini-sternotomy does not seem to offer any advantage compared to the traditional approach.

Management of aortic stenosis: a systematic review of clinical practice guidelines and recommendations

Multiple guidelines exist for the management of aortic stenosis (AS). We systematically reviewed current guidelines and recommendations, developed by national or international medical organizations, on management of AS to aid clinical decision-making. Publications in MEDLINE and EMBASE between 1 June 2010 and 15 January 2021 were identified. Additionally, the International Guideline Library, National Guideline Clearinghouse, National Library for Health Guidelines Finder, Canadian Medical Association Clinical Practice Guidelines Infobase, and websites of relevant organizations were searched. Two reviewers independently screened titles and abstracts. Two reviewers assessed rigour of guideline development and extracted the recommendations. Of the seven guidelines and recommendations retrieved, five showed considerable rigour of development. Those rigourously developed, agreed on the definition of severe AS and diverse haemodynamic phenotypes, indications and contraindications for intervention in symptomatic severe AS, surveillance intervals in asymptomatic severe AS, and the importance of multidisciplinary teams (MDTs) and shared decision-making. Discrepancies exist in age and surgical risk cut-offs for recommending surgical aortic valve replacement (SAVR) vs. transcatheter aortic valve implantation (TAVI), the use of biomarkers and complementary multimodality imaging for decision-making in asymptomatic patients and surveillance intervals for non-severe AS. Contemporary guidelines for AS management agree on the importance of MDT involvement and shared decision-making for individualized treatment and unanimously indicate valve replacement in severe, symptomatic AS. Discrepancies exist in thresholds for age and procedural risk used in choosing between SAVR and TAVI, role of biomarkers and complementary imaging modalities to define AS severity and risk of progression in asymptomatic patients.

Preprocedural circulating galectin-3 and the risk of mortality after transcatheter aortic valve replacement: a systematic review and meta-analysis

Background: Galectin-3 may predict mortality for patients with aortic stenosis (AS) after transcatheter aortic valve replacement (TAVR). However, the results were inconsistent. We aimed to evaluate the association between baseline galectin and mortality after TAVR in a meta-analysis.

Methods: Related follow-up studies were obtained by systematic search of PubMed, Cochrane’s Library, and Embase databases. Both the fixed- and the random-effect models were used for the meta-analysis. Subgroup analyses were performed to evaluate the influences of study characteristics on the outcome.

Results: Five prospective cohort studies with 854 patients were included, with a follow-up period between 1 and 1.9 years. Patients with higher baseline circulating galectin-3 had an increased risk of all-cause mortality after TAVR (random-effects model: risk ratio [RR]: 1.63, 95% confidence interval [CI]: 1.19–2.23, P=0.002; fixed-effects model: RR: 1.62, 95% CI: 1.19–2.20, P=0.002; I² = 4%). Adjustment of estimated glomerular filtration rate (RR: 1.73, P=0.02) or B-type natriuretic peptide (BNP) or N-terminal pro-BNP (RR: 1.83, P=0.02) did not significantly affect the result. A trend of stronger association between higher baseline circulating galectin-3 and increased risk of all-cause mortality after TAVR was observed in studies with an enzyme-linked fluorescent assay (ELFA) (RR: 3.04, P=0.003) compared with those with an enzyme-linked immunosorbent assay (ELISA) (RR: 1.42, P=0.04; P for subgroup difference =0.06).

Conclusion: Higher circulating galectin-3 before the procedure may predict all-cause mortality of AS patients after TAVR.