Symptoms, disease severity and treatment of adults with a new diagnosis of severe aortic stenosis

Deep Learning Algorithms to Detect Murmurs Associated With Structural Heart Disease

Background The success of cardiac auscultation varies widely among medical professionals, which can lead to missed treatments for structural heart disease. Applying machine learning to cardiac auscultation could address this problem, but despite recent interest, few algorithms have been brought to clinical practice. We evaluated a novel suite of Food and Drug Administration-cleared algorithms trained via deep learning on >15 000 heart sound recordings. Methods and Results We validated the algorithms on a data set of 2375 recordings from 615 unique subjects. This data set was collected in real clinical environments using commercially available digital stethoscopes, annotated by board-certified cardiologists, and paired with echocardiograms as the gold standard. To model the algorithm in clinical practice, we compared its performance against 10 clinicians on a subset of the validation database. Our algorithm reliably detected structural murmurs with a sensitivity of 85.6% and specificity of 84.4%. When limiting the analysis to clearly audible murmurs in adults, performance improved to a sensitivity of 97.9% and specificity of 90.6%. The algorithm also reported timing within the cardiac cycle, differentiating between systolic and diastolic murmurs. Despite optimizing acoustics for the clinicians, the algorithm substantially outperformed the clinicians (average clinician accuracy, 77.9%; algorithm accuracy, 84.7%.) Conclusions The algorithms accurately identified murmurs associated with structural heart disease. Our results illustrate a marked contrast between the consistency of the algorithm and the substantial interobserver variability of clinicians. Our results suggest that adopting machine learning algorithms into clinical practice could improve the detection of structural heart disease to facilitate patient care.

Aortic valve intervention rates in patients of different ethnicity with severe aortic stenosis in Leicestershire, UK

OBJECTIVES

To explore the ethnic differences in patients undergoing aortic valve (AV) intervention for severe aortic stenosis (AS) in Leicestershire, UK.

METHODS

Retrospective cohort study of all surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI) at a single tertiary centre between April 2017 and March 2022, using local registry data.

RESULTS

Of the 1231 SAVR and 815 TAVI performed, 6.5% and 3.7% were in ethnic minority patients, respectively. Based on the 2011 Census data for those with a Leicestershire postcode, crude cumulative rate of SAVR (n=489) was 0.64 per 1000 population overall and 0.69, 0.46 and 0.36 in White, Asian and Black populations, respectively; and 0.50 per 1000 population overall for TAVI (n=383), with 0.59, 0.16 and 0.06 for White, Asian and Black populations, respectively. Asians undergoing SAVR and TAVI were 5 and 3 years younger, respectively, than white patients with more comorbidities and a worse functional status.The age-adjusted cumulative rates for SAVR were 0.62 vs 0.72 per 1000 population for White and Asian patients and 0.51 vs 0.39 for TAVI. Asians were less likely to undergo SAVR and TAVI than White patients, with a risk ratio (RR) of 0.66 (0.50-0.87) and 0.27 (0.18-0.43), respectively, but the age-adjusted RR was not statistically significant.

CONCLUSION

The crude rates of AV interventions are lower in Asian patients compared with the White population in Leicestershire, although age-adjusted rates were not statistically different. Further research to determine the sociodemographic differences in prevalence, incidence, mechanisms and treatment of AS across the UK is required.

Challenging Decision-Making Between Transcatheter Aortic Valve Implantation and Aortic Valve Surgery: A Case of a Jehovah's Witness Patient With Severe Symptomatic Aortic Stenosis Coexisting With Severe Mitral Regurgitation and Bicuspid Aortic Valve

A 73-year-old Jehovah's witness man with a bicuspid aortic valve and a history of epilepsy presented to the emergency room with chest pain and dyspnea. Echocardiography revealed normal left ventricular systolic function, but also revealed severe aortic stenosis and severe mitral regurgitation. Coronary angiography and computerized tomography angiography ruled out any significant coronary artery disease and aortic dissection, respectively. In view of his religious views, transcatheter aortic valve implantation was considered more suitable than aortic valve surgery and was successful with a stable postoperative state. This case reaffirms that autonomy should be maintained while considering the best interest of patients in decision-making.

Severe aortic stenosis management in heart valve centres compared with primary/secondary care centres

OBJECTIVE

Current guidelines recommend use of heart valve centres (HVCs) to deliver optimal quality of care for patients with valve disease but there is no evidence to support this. The hypothesis of this study is that patient care with severe aortic stenosis (AS) will differ in HVCs compared with satellite centres. We aimed to compare the treatment of patients with AS at HVCs (tertiary care hospitals with full access to AS interventions) to satellites (hospitals without such access).

METHODS

IMPULSE enhanced is a European, observational, prospective registry enrolling consecutive patients with newly diagnosed severe AS at four HVCs and 10 satellites. Clinical characteristics, interventions performed and outcomes up to 1 year by site-type were examined.

RESULTS

Among 790 patients, 594 were recruited in HVCs and 196 in satellites. At baseline, patients in HVCs had more severe valve disease (higher peak aortic velocity (4.3 vs 4.1 m/s; p=0.008)) and greater comorbidity (coronary artery disease (CAD) (44% vs 27%; p<0.001) prior myocardial infarction (MI) (11% vs 5.1%; p=0.011) and chronic pulmonary disease (17% vs 8.9%; p=0.007)) than those presenting in satellites. An aortic valve replacement was performed more often by month 3 in HVCs than satellites in the overall population (52.6% of vs 31.3%; p<0.001) and in symptomatic patients (66.7% vs 43.2%, p<0.001). One-year survival rate was higher for patients in HVCs than satellites (HR2.19; 95% CI 1.28 to 3.73 total population and 2.89 (95%CI 1.64 to 5.11) for symptomatic patients.

CONCLUSIONS

Our data support the implementation of referral pathways that direct patients to HVCs performing both surgery and transcatheter interventions.

TRIAL REGISTRATION NUMBER

NCT03112629.

The Role of Transcatheter Aortic Valve Replacement in Asymptomatic Aortic Stenosis: A Feasibility Analysis

Surgical aortic valve replacement (SAVR) is the current treatment of choice for good surgical candidates with moderate to severe symptomatic aortic stenosis (AS). As transcatheter aortic valvular replacement (TAVR) has shown an improved one and two-year all-cause mortality, it has been chosen for moderately symptomatic severe AS patients. The purpose of this review was to perform a clinical comparison of TAVR vs. SAVR and to analyze the Health Index Factor (HIF) that makes TAVR a treatment of choice in asymptomatic AS patients. 

An extensive literature search of PubMed, Cochrane, and Embase databases was performed using the keywords “Aortic stenosis”, “SAVR”, “TAVR”, and “Asymptomatic”. A total of 45 prospective randomized clinical trials in the English language that were published from the year 2000 onwards were included in the final analysis. It has been found that 59.3% of asymptomatic AS patients are likely to die in the next five years without proactive treatment. Multiple studies have proven that early intervention with aortic valve replacement is superior to conservative treatment in severe asymptomatic AS; however, the choice between SAVR and TAVR is not well established. The NOTION Trial, SURTAVI Trail, and PARTNER 3 study have shown the non-inferiority of TAVR over SAVR, during one-year follow-up for low surgical risk patients. Evolut Low-Risk study and Early TAVR are the only two prospective studies performed to date that have enrolled patients with asymptomatic severe AS. The Evolut Trial demonstrated no difference in all-cause mortality at 30 days (1.3% vs. 4.8%. p=0.23), and 12 days (1.3% vs. 6.5%, p=0.11). Additionally, TAVR also decreases the risk of post-procedural atrial fibrillation, acute kidney injury (AKI), and rehospitalization, and leads to significant improvement in the mean trans-aortic pressure gradient. TAVR also showed marked improvement in the 30-day Quality of Life (QOL) index, where SAVR did not report any significant change in the QOL index. However, the official recommendations of Early TAVR are still awaited. TAVR has consistently shown a statistically non-significant difference in case mortality, risk of stroke, and rehospitalization with moderate to high surgical risk patients whereby recent initial trials have shown significant improvement in the QOL index and hemodynamic index for patients with asymptomatic disease. More extensive studies are required to prove the risk stratifications, long-term outcomes, and clinical characteristics that would make TAVR a preferred intervention in asymptomatic patients.

Exercise Testing in Aortic Stenosis: Safety, Tolerability, Clinical Benefits and Prognostic Value

Background: Routine exercise testing in asymptomatic patients with valvular heart disease (VHD) better classifies the hemodynamic severity of valve stenosis or regurgitation, and describes the symptomatic status and functional capacity of the patient. This is crucial for planned surveillance and optimal timing of surgery, particularly for aortic stenosis (AS), because once symptoms occur, there is a sharp increase in the risk of sudden death unless valve intervention is performed. Purpose: To conduct a focused clinical review on the benefits of exercise testing in patients with AS. Methods: The electronic database PubMed was systematically searched for relevant retrospective and prospective cohort studies reporting on the safety, feasibility and tolerability of exercise testing in VHD, with a special focus on AS. Results and conclusions: In patients with significant AS, exercise testing is safe, feasible and reveals symptoms in a significant proportion of patients. In addition, serial testing has incremental prognostic value over a baseline test alone. Exercise testing in patients with AS is underused and should be performed routinely to refine the hemodynamic severity of AS.

Uncovering the treatable burden of severe aortic stenosis in the UK

OBJECTIVE

To estimate the population prevalence and treatable burden of severe aortic stenosis (AS) in the UK.

METHODS

We adapted a contemporary model of the population profile of symptomatic and asymptomatic severe AS in Europe and North America to estimate the number of people aged ≥55 years in the UK who might benefit from surgical aortic valve replacement (SAVR) or transcatheter aortic valve implantation (TAVI).

RESULTS

With a point prevalence of 1.48%, we estimate that 291 448 men and women aged ≥55 years in the UK had severe AS in 2019. Of these, 68.3% (199 059, 95% CI 1 77 201 to 221 355 people) would have been symptomatic and, therefore, more readily treated according to their surgical risk profile; the remaining 31.7% of cases (92 389, 95% CI 70 093 to 144 247) being asymptomatic. Based on historical patterns of intervention, 58.4% (116 251, 95% CI 106 895 to 1 25 606) of the 199 059 symptomatic cases would qualify for SAVR, with 7208 (95% CI 7091 to 7234) being assessed as being in a high, preoperative surgical risk category. Among the remaining 41.6% (82 809, 95% CI 73 453 to 92 164) of cases potentially unsuitable for SAVR, an estimated 61.7% (51 093, 95% CI 34 780 to 67 655) might be suitable for TAVI. We estimate that 172 859 out of 291 448 prevalent cases of severe AS (59.3%) will subsequently die within 5 years without proactive management.

CONCLUSIONS

These data suggest a high burden of severe AS in the UK requiring surgical or transcatheter intervention that challenges the ongoing capacity of the National Health Service to meet the needs of those affected.

Community-based aortic stenosis detection: clinical and echocardiographic screening during influenza vaccination

Background

Degenerative aortic stenosis (AS), the most common valvular heart disease in the Western world, is often diagnosed late when the mortality risk becomes substantial. We determined the feasibility of AS screening during influenza vaccination at general practitioner (GP) surgeries in the UK.

Methods

Consecutive subjects aged >65 years presenting to a GP for influenza vaccination underwent heart auscultation and 2D echocardiography (V-scan). Based on these findings, a patient management strategy was determined (referral to cardiologist, review within own practice or no follow-up measures) and status at 3 months was determined.

Results

167 patients were enrolled with a mean age of 75 years. On auscultation, a heart murmur was detected in 30 of 167 (18%) patients (6 subjects with an AS-specific and 24 with a non-specific murmur). 75.2% of those with no murmur had a negative V-scan finding. Conversely, 16 of 30 (53%) patients with any murmur had an abnormal V-scan finding that was largely related to the aortic valve. Using clinical auscultation and V-scan screening, a decision not to pursue follow-up measures was taken in 147 (88%) cases, whereas 18 (10.8%) subjects were referred onward; with 5 of 18 (27.8%) and 3 of 18 (16.7%) being diagnosed with mild and moderate AS.

Conclusions

Our pilot study confirms feasibility of valvular heart disease screening in the elderly in a primary care setting. Using simple and inexpensive diagnostic measures and 7.3 million UK inhabitants undergoing influenza vaccination, nationwide screening could potentially identify 130 000 patients with moderate AS and a significant number of patients with severe AS.

Management of patients with severe aortic stenosis in the TAVI-era: how recent recommendations are translated into clinical practice

Objective

Approximately 3.4% of adults aged >75 years suffer from aortic stenosis (AS). Guideline indications for aortic valve replacement (AVR) distinguish between patients with symptomatic and asymptomatic severe AS. The present analysis aims to assess contemporary practice in the treatment of severe AS across Europe and identify characteristics associated with treatment decisions, namely denial of AVR in symptomatic patients and assignment of asymptomatic patients to AVR.

Methods

Participants of the prospective, multinational IMPULSE database of patients with severe AS were grouped according to AS symptoms, and stratified into subgroups based on assignment to/denial of AVR.

Results

Of 1608 symptomatic patients, 23.8% did not undergo AVR and underwent medical treatment. Denial was independently associated with multiple factors, including severe frailty (p=0.024); mitral (p=0.002) or tricuspid (p=0.004) regurgitation grade III/IV, and the presence of renal impairment (p=0.017). Of 392 asymptomatic patients, 86.5% had no prespecified indication for AVR. Regardless, 36.3% were assigned to valve replacement. Those with an indexed aortic valve area (AVA; p=0.045) or left ventricular ejection fraction (LVEF; p<0.001) below the study median; or with a left ventricular end systolic diameter above the study median (p=0.007) were more likely to be assigned to AVR.

Conclusions

There may be considerable discrepancies between guideline-based recommendations and clinical practice decision-making in the treatment of AS. It appears that guidelines may not fully capture the complete clinical spectrum of patients with AS. Thus, there is a need to find ways to increase their acceptance and the rate of adoption.

IMPULSE: the impact of gender on the presentation and management of aortic stenosis across Europe

Aims

There is an increasing awareness of gender-related differences in patients with severe aortic stenosis and their outcomes after surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI).

Methods

Data from the IMPULSE registry were analysed. Patients with severe aortic stenosis (AS) were enrolled between March 2015 and April 2017 and stratified by gender. A subgroup analysis was performed to assess the impact of age.

Results

Overall, 2171 patients were enrolled, and 48.0% were female. Women were characterised by a higher rate of renal impairment (31.7 vs 23.3%; p<0.001), were at higher surgical risk (EuroSCORE II: 4.5 vs 3.6%; p=0.001) and more often in a critical preoperative state (7.0vs 4.2%; p=0.003). Men had an increased rate of previous cardiac surgery (9.4 vs 4.7%; p<0.001) and a reduced left ventricular ejection fraction (4.9 vs 1.3%; p<0.001). Concomitant mitral and tricuspid valve disease was substantially more common among women. Symptoms were highly prevalent in both women and men (83.6 vs 77.3%; p<0.001). AVR was planned in 1379 cases. Women were more frequently scheduled to undergo TAVI (49.3 vs 41.0%; p<0.001) and less frequently for SAVR (20.3 vs 27.5%; p<0.001).

Conclusions

The present data show that female patients with severe AS have a distinct patient profile and are managed in a different way to males. Gender-based differences in the management of patients with severe AS need to be taken into account more systematically to improve outcomes, especially for women.

Narrative review of the role of artificial intelligence to improve aortic valve disease management

Valvular heart disease (VHD) is a chronic progressive condition with an increasing prevalence in the Western world due to aging populations. VHD is often diagnosed at a late stage when patients are symptomatic and the outcomes of therapy, including valve replacement, may be sub-optimal due the development of secondary complications, including left ventricular (LV) dysfunction. The clinical application of artificial intelligence (AI), including machine learning (ML), has promise in supporting not only early and more timely diagnosis, but also hastening patient referral and ensuring optimal treatment of VHD. As physician auscultation lacks accuracy in diagnosis of significant VHD, computer-aided auscultation (CAA) with the help of a commercially available digital stethoscopes improves the detection and classification of heart murmurs. Although used little in current clinical practice, CAA can screen large populations at low cost with high accuracy for VHD and faciliate appropriate patient referral. Echocardiography remains the next step in assessment and planning management and AI is delivering major changes in speeding training, improving image quality by pattern recognition and image sorting, as well as automated measurement of multiple variables, thereby improving accuracy. Furthermore, AI then has the potential to hasten patient disposal, by automated alerts for red-flag findings, as well as decision support in dealing with results. In management, there is great potential in ML-enabled tools to support comprehensive disease monitoring and individualized treatment decisions. Using data from multiple sources, including demographic and clinical risk data to image variables and electronic reports from electronic medical records, specific patient phenotypes may be identified that are associated with greater risk or modeled to the estimate trajectory of VHD progression. Finally, AI algorithms are of proven value in planning intervention, facilitating transcatheter valve replacement by automated measurements of anatomical dimensions derived from imaging data to improve valve selection, valve size and method of delivery.

Impact of selected comorbidities on the presentation and management of aortic stenosis

Background

Contemporary data regarding the impact of comorbidities on the clinical presentation and management of patients with severe aortic stenosis (AS) are scarce.

Methods

Prospective registry of severe patients with AS across 23 centres in nine European countries.

Results

Of the 2171 patients, chronic kidney disease (CKD 27.3%), left ventricular ejection fraction (LVEF) <50% (22.0%), atrial fibrillation (15.9%) and chronic obstructive pulmonary disease (11.4%) were the most prevalent comorbidities (49.3% none, 33.9% one and 16.8% ≥2 of these). The decision to perform aortic valve replacement (AVR) was taken in a comparable proportion (67%, 72% and 69%, in patients with 0, 1 and ≥2 comorbidities; p=0.186). However, the decision for TAVI was more common with more comorbidities (35.4%, 54.0% and 57.0% for no, 1 and ≥2; p<0.001), while the decision for surgical AVR (SAVR) was decreased with increasing comorbidity burden (31.9%, 17.4% and 12.3%; p<0.001). The proportion of patients with planned AVRs that were performed within 3 months was significantly higher in patients with 1 or ≥2 comorbidities than in those without (8.7%, 10.0% and 15.7%; p<0.001). Furthermore, the mean time to AVR was significantly shorter in patients with one (30.5 days) or ≥2 comorbidities (30.8 days) than in those without (35.7 days; p=0.012). Patients with reduced LVEF tended to be offered an AVR more frequently and with a shorter delay while patients with CKD were less frequently treated.

Conclusions

Comorbidities in severe patients with AS affect the presentation and management of patients with severe AS. TAVI was offered more often than SAVR and performed within a shorter time period.

Differences in the presentation and management of patients with severe aortic stenosis in different European centres

Background

An investigation into differences in the management and treatment of severe aortic stenosis (AS) between Germany, France and the UK may allow benchmarking of the different healthcare systems and identification of levers for improvement.

Methods

Patients with a diagnosis of severe AS under management at centres within the IMPULSE and IMPULSE enhanced registries were eligible.

Results

Data were collected from 2052 patients (795 Germany; 542 France; 715 UK). Patients in Germany were older (79.8 years), often symptomatic (89.5%) and female (49.8%) and had a lower EF (53.8%) than patients in France and UK. Comorbidities were more common and they had a higher mean Euroscore II.

Aortic valve replacement (AVR) was planned within 3 months in 70.2%. This was higher (p<0.001) in Germany than France/ UK. Of those with planned AVR, 82.3% received it within 3 months with a gradual decline (Germany>France> UK; p<0.001). In 253 patients, AVR was not performed, despite planned. Germany had a strong transcatheter aortic valve implantation (TAVI) preference (83.2%) versus France/ UK (p<0.001). Waiting time for TAVI was shorter in Germany (24.9 days) and France (19.5 days) than UK (40.3 days).

Symptomatic patients were scheduled for an AVR in 79.4% (Germany> France> UK; p<0.001) and performed in 83.6% with a TAVI preference (73.1%). 20.4% of the asymptomatic patients were intervened.

Conclusion

Patients in Germany had more advanced disease. The rate of intervention within 3 months after diagnosis was startlingly low in the UK. Asymptomatic patients without a formal indication often underwent an intervention in Germany and France.

Prespecified Risk Criteria Facilitate Adequate Discharge and Long-Term Outcomes After Transfemoral Transcatheter Aortic Valve Implantation

Background

Despite the availability of guidelines for the performance of transcatheter aortic valve implantation (TAVI), current treatment pathways vary between countries and institutions, which impact on the mean duration of postprocedure hospitalization.

Methods and Results

This was a prospective, multicenter registry of 502 patients to validate the appropriateness of discharge timing after transfemoral TAVI, using prespecified risk criteria from FAST‐TAVI (Feasibility and Safety of Early Discharge After Transfemoral [TF] Transcatheter Aortic Valve Implantation), based on hospital events within 1‐year after discharge. The end point—a composite of all‐cause mortality, vascular access–related complications, permanent pacemaker implantation, stroke, cardiac rehospitalization, kidney failure, and major bleeding—was reached in 27.0% of patients (95% CI, 23.3–31.2) within 1 year after intervention; 7.5% (95% CI, 5.5–10.2) had in‐hospital complications before discharge and 19.6% (95% CI, 16.3–23.4) within 1 year after discharge. Overall mortality within 1 year after discharge was 7.3% and rates of cardiac rehospitalization 13.5%, permanent pacemaker implantation 4.2%, any stroke 1.8%, vascular‐access–related complications 0.7%, life‐threatening bleeding 0.7%, and kidney failure 0.4%. Composite events within 1 year after discharge were observed in 18.8% and 24.3% of patients with low risk of complications/early (≤3 days) discharge and high risk and discharged late (>3 days) (concordant discharge), respectively. Event rate in patients with discordant discharge was 14.3% with low risk but discharged late and increased to 50.0% in patients with high risk but discharged in ≤3 days.

Conclusions

The FAST‐TAVI risk assessment provides a tool for appropriate, risk‐based discharge that was validated with the 1‐year event rate after transfemoral TAVI.

Registration

URL: https://www.ClinicalTrials.gov; Unique identifier: NCT02404467.

EDUCATIONAL SERIES ON THE SPECIALIST VALVE CLINIC: Challenges in the diagnosis and management of valve disease: the case for the specialist valve clinic

Valvular heart disease (VHD) is responsible for a major societal and economic burden. Incidence and prevalence of VHD are high and increase as the population ages, creating the next epidemic. In Western countries, the etiology is mostly degenerative or functional disease and strikes an elderly population with multiple comorbidities. Epidemiological studies have shown that VHD is commonly underdiagnosed, leading to patients presenting late in their disease course, to an excess risk of mortality and morbidity and to a missed opportunity for intervention. Once diagnosed, VHD is often undertreated with patients unduly denied intervention, the only available curative treatment. This gap between current recommendations and clinical practice and the marked under-treatment is at least partially related to poor knowledge of current National and International Societies Guidelines. Development of a valvular heart team involving multidisciplinary valve specialists including clinicians, imaging specialists, interventional cardiologists and surgeons is expected to fill these gaps and to offer an integrated care addressing all issues of patient management from evaluation, risk-assessment, decision-making and performance of state-of-the-art surgical and transcatheter interventions. The valvular heart team will select the right treatment for the right patient, improving cost-effectiveness and ultimately patients' outcomes.