The Association of Moderate Aortic Stenosis with Poor Survival is Modified by Age and Left Ventricular Function

Impact of Renal Function on Myocardial Remodeling and Outcomes in Patients With Moderate Aortic Stenosis

BACKGROUND

Patients with moderate aortic stenosis (AS) and cardiac damage have poor prognosis, and whether early aortic valve replacement benefits these patients is under investigation. However, besides valvular hemodynamics, comorbidities such as chronic kidney disease (CKD) can contribute to myocardial damage and affect prognosis. The aim of this study was to investigate the impact of renal function on myocardial remodeling and outcomes in patients with moderate AS.

METHODS

The study cohort included 865 consecutive patients diagnosed with moderate AS (aortic valve area > 1.0 and ≤1.5 cm2, mean gradient > 20 mmHg) between 2008 and 2020. Patients were categorized into five stages of CKD according to estimated glomerular filtration rate. Echocardiographic measures of myocardial remodeling and the composite outcome of all-cause mortality and heart failure hospitalization were assessed.

RESULTS

Higher CKD stage was associated with greater valvuloarterial impedance, as well as greater left ventricular (LV) hypertrophy, worse LV diastolic function, and lower LV and left atrial strain, despite similar AS severity. These associations were independent of age, sex, comorbidities, and LV pressure overload. During a median follow-up period of 4.0 years, 310 composite outcome events (39.3%) occurred, including 258 deaths (32.7%). Severe CKD (stage 4 or 5) and myocardial dysfunction were independent predictors of the composite outcome, after adjustment for key clinical variables including aortic valve replacement. Mediation analysis showed that myocardial dysfunction partially mediated the impact of renal function on outcome.

CONCLUSIONS

In patients with moderate AS, renal dysfunction was independently associated with adverse myocardial remodeling and dysfunction, irrespective of valvular hemodynamics. The role of earlier intervention in patients with moderate AS whose cardiac damage is driven by comorbidities, rather than AS itself, warrants further investigation.

Prognostic value of extraaortic-valvular cardiac damage in patients with moderate aortic stenosis and reduced left ventricular ejection fraction

PURPOSE

The extraaortic-valvular cardiac damage (EVCD) Stage has shown potential for risk stratification for patients with aortic stenosis (AS). This study aimed to examine the usefulness of the EVCD Stage in risk stratification of patients with moderate AS and reduced left ventricular ejection fraction (LVEF).

METHODS

Clinical data from patients with moderate AS (aortic valve area, .60-.85 cm2/m2; peak aortic valve velocity, 2.0-4.0 m/s) and reduced LVEF (LVEF 20%-50%) were analyzed during 2010-2019. Patients were categorized into three groups: EVCD Stages 1 (LV damage), 2 (left atrium and/or mitral valve damage), and 3/4 (pulmonary artery vasculature and/or tricuspid valve damage or right ventricular damage). The primary endpoint included a composite of cardiac death and heart failure hospitalization, with non-cardiac death as a competing risk.

RESULTS

The study included 130 patients (mean age 76.4 ± 6.8 years; 62.3% men). They were categorized into three groups: 26 (20.0%) in EVCD Stage 1, 66 (50.8%) in Stage 2, and 48 (29.2%) in Stage 3/4. The endpoint occurred in 54 (41.5%) patients during a median follow-up of 3.2 years (interquartile range, 1.4-5.1). Multivariate analysis indicated EVCD Stage 3/4 was significantly associated with the endpoint (hazard ratio 2.784; 95% confidence interval 1.197-6.476; P = .017) compared to Stage 1, while Stage 2 did not (hazard ratio 1.340; 95% confidence interval .577-3.115; P = .500).

CONCLUSION

The EVCD staging system may aid in the risk stratification of patients with moderate AS and reduced LVEF.

Predictors of Disease Progression and Adverse Clinical Outcomes in Patients With Moderate Aortic Stenosis Using an Artificial Intelligence-Based Software Platform

Patients with moderate aortic stenosis (AS) have a greater risk of adverse clinical outcomes than that of the general population. How this risk compares with those with severe AS, along with factors associated with outcomes and disease progression, is less clear. We analyzed serial echoes (from 2017 to 2019) from a single healthcare system using Tempus Next (Chicago, Illinois) software. AS severity was defined according to American Heart Association/American College of Cardiology guidelines. Outcomes of interest included death or heart failure hospitalization. We used Cox proportional hazards models and logistic regression to identify predictors of clinical outcome and disease progression, respectively. From 82,805 echoes for 61,546 patients, 1,770; 914; 565; and 1,463 patients had no, mild, moderate, or severe AS, respectively. Both patients with moderate and those with severe AS experienced a similar prevalence of adverse clinical outcomes (p = 0.45) that was significantly greater than that of patients without AS (p <0.01). In patients with moderate AS, atrial fibrillation (hazard ratio 3.29, 95% confidence interval 1.79 to 6.02, p <0.001) and end-stage renal disease (hazard ratio 3.34, 95% confidence interval 1.87 to 5.95, p <0.001) were associated with adverse clinical outcomes. One-third of patients with moderate AS with a subsequent echo (139/434) progressed to severe AS within 1 year. In conclusion, patients with moderate AS can progress rapidly to severe AS and experience a similar risk of adverse clinical outcomes; predictors include atrial fibrillation and low left ventricular ejection fraction. Machine learning algorithms may help identify these patients. Whether these patients may warrant earlier intervention merits further study.

Moderate Aortic Valve Stenosis Is Associated With Increased Mortality Rate and Lifetime Loss: Systematic Review and Meta-Analysis of Reconstructed Time-to-Event Data of 409 680 Patients

BACKGROUND

The mortality risk attributable to moderate aortic stenosis (AS) remains incompletely characterized and has historically been underestimated. We aim to evaluate the association between moderate AS and all-cause death, comparing it with no/mild AS (in a general referral population and in patients with heart failure with reduced ejection fraction).

METHODS AND RESULTS

A systematic review and pooled meta-analysis of Kaplan-Meier-derived reconstructed time-to-event data of studies published by June 2023 was conducted to evaluate survival outcomes among patients with moderate AS in comparison with individuals with no/mild AS. Ten studies were included, encompassing a total of 409 680 patients (11 527 with moderate AS and 398 153 with no/mild AS). In the overall population, the 15-year overall survival rate was 23.3% (95% CI, 19.1%-28.3%) in patients with moderate AS and 58.9% (95% CI, 58.1%-59.7%) in patients with no/mild aortic stenosis (hazard ratio [HR], 2.55 [95% CI, 2.46-2.64]; P<0.001). In patients with heart failure with reduced ejection fraction, the 10-year overall survival rate was 15.5% (95% CI, 10.0%-24.0%) in patients with moderate AS and 37.3% (95% CI, 36.2%-38.5%) in patients with no/mild AS (HR, 1.83 [95% CI, 1.69-2.0]; P<0.001). In both populations (overall and heart failure with reduced ejection fraction), these differences correspond to significant lifetime loss associated with moderate AS during follow-up (4.4 years, P<0.001; and 1.9 years, P<0.001, respectively). A consistent pattern of elevated mortality rate associated with moderate AS in sensitivity analyses of matched studies was observed.

CONCLUSIONS

Moderate AS was associated with higher risk of death and lifetime loss compared with patients with no/mild AS.

Prognostic Signals From Moderate Valve Disease in Big Data: An Artefact of Digital Imaging and Communications in Medicine Structured Reporting?

BACKGROUND

Recent studies have identified an association between moderate aortic stenosis (AS) and outcome. We assessed whether Digital Imaging and Communications in Medicine (DICOM) structured reporting (SR), which captures and inserts echocardiographic measurements and text data directly into radiological reports, may lead to misclassifying patients with severe AS as moderate.

METHODS

Moderate or severe AS cases were filtered from an echocardiography data set based on aortic valve area (AVA) < 1.5 cm2, indexed AVA (AVAi) ≤ 0.85 cm2/m2, mean pressure gradient ≥ 25 mm Hg, dimensionless severity index (DSI) ≤ 0.5, or peak velocity > 3 m/sec. Data validation was conducted by verification of each parameter. All echocardiographic parameters and definitions of AS were compared pre- and postvalidation by taking differences in measurements. Misclassification rates were assessed by determining the percentage of cases that changed AS severity classification and impact on outcomes. Patients were followed over 4.3 ± 1.5 years.

RESULTS

Of 2,595 validated echocardiograms with AS, up to 36% of the echocardiographic parameters for AS criteria had a >10% difference between DICOM-SR and manual validation, the highest with mean pressure gradient (36%) and the lowest with DSI (6.5%). The validation process changed the reported degree of AS in up to 20.6% of echocardiograms with resultant changes in AS severity and its association with mortality or heart failure-related hospitalizations. In contrast to multiple quantitative metrics in DICOM-SR after manual validation, clinicians' evaluation of AS severity was unable to distinguish composite outcomes over 3 years between moderate and severe AS. The risk of composite outcomes was significantly increased when severe AS was evidenced by at least 1 echocardiographic parameter of severe AS (hazard ratio = 1.24; 95% CI, 1.12-1.37; P < .001). The greatest hazard was based on DSI only (hazard ratio = 1.26; 95% CI, 1.10-1.44; P < .001), which was higher after manual validation compared to DICOM-SR. Averaging of repeated echo measures including invalid values contributed the most to erroneous data.

CONCLUSIONS

Nonpeak data in DICOM-SR led to incorrect categorization of a high proportion of patients based on AS severity definitions. Standardization of data fields and curation to ensure that only peak values are imported from DICOM-SR data are essential.

Transcatheter Aortic Valve Replacement in Patients With Reduced Ejection Fraction and Nonsevere Aortic Stenosis

BACKGROUND

The potential benefit of transcatheter aortic valve replacement (TAVR) in patients with nonsevere aortic stenosis (AS) and heart failure is controversial. This study aimed to assess outcomes of patients with nonsevere low-gradient AS (LGAS) and reduced left ventricular ejection fraction undergoing TAVR or medical management.

METHODS

Patients undergoing TAVR for LGAS and reduced left ventricular ejection fraction (<50%) were included in a multinational registry. True-severe low-gradient AS (TS-LGAS) and pseudo-severe low-gradient AS (PS-LGAS) were classified according to computed tomography-derived aortic valve calcification thresholds. A medical control group with reduced left ventricular ejection fraction and moderate AS or PS-LGAS was used (Medical-Mod). Adjusted outcomes between all groups were compared. Among patients with nonsevere AS (moderate or PS-LGAS), outcomes after TAVR and medical therapy were compared using propensity score-matching.

RESULTS

A total of 706 LGAS patients undergoing TAVR (TS-LGAS, N=527; PS-LGAS, N=179) and 470 Medical-Mod patients were included. After adjustment, both TAVR groups showed superior survival compared with Medical-Mod patients (all P<0.001), while no difference was found between TS-LGAS and PS-LGAS TAVR patients (P=0.96). After propensity score-matching among patients with nonsevere AS, PS-LGAS TAVR patients showed superior 2-year overall (65.4%) and cardiovascular survival (80.4%) compared with Medical-Mod patients (48.8% and 58.5%, both P≤0.004). In a multivariable analysis including all patients with nonsevere AS, TAVR was an independent predictor of survival (hazard ratio, 0.39 [95% CI, 0.27-0.55]; P<0.0001).

CONCLUSIONS

Among patients with nonsevere AS and reduced left ventricular ejection fraction, TAVR represents a major predictor of superior survival. These results reinforce the need for randomized-controlled trials comparing TAVR versus medical management in heart failure patients with nonsevere AS.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04914481.