Multimarker Approach to Identify Patients With Higher Mortality and Rehospitalization Rate After Surgical Aortic Valve Replacement for Aortic Stenosis

Multimarker Approach to Improve Risk Stratification of Patients Undergoing Transcatheter Aortic Valve Implantation

Background

A blood multimarker approach may be useful to enhance risk stratification in patients undergoing TAVI.

Objectives

The objective of this study was to determine the prognostic value of multiple blood biomarkers in transcatheter aortic valve implantation (TAVI) patients.

Methods

In this prospective study, several blood biomarkers of cardiovascular function, inflammation, and renal function were measured in 362 patients who underwent TAVI. The cohort was divided into 3 groups according to the number of elevated blood biomarkers (ie, ≥ median value for the whole cohort) for each patient before the procedure. Survival analyses were conducted to evaluate the association between blood biomarkers and risk of adverse event following TAVI.

Results

During a median follow-up of 2.5 (IQR: 1.9-3.2) years, 34 (9.4%) patients were rehospitalized for heart failure, 99 (27%) patients died, and 113 (31.2%) met the composite endpoint of all-cause mortality or heart failure rehospitalization. Compared to patients with 0 to 3 elevated biomarkers (referent group), those with 4 to 7 and 8 to 9 elevated biomarkers had a higher risk of all-cause mortality (HR: 1.54 [95% CI: 0.84-2.80], P = 0.16, and HR: 2.81 [95% CI: 1.53-5.15], P < 0.001, respectively) and of the composite endpoint (HR: 1.65 [95% CI: 0.95-2.84], P = 0.07, and HR: 2.67 [95% CI: 1.52-4.70] P < 0.001, respectively). Moreover, adding the number of elevated blood biomarkers into the clinical multivariable model provided significant incremental predictive value for all-cause mortality (Net Reclassification Index = 0.71, P < 0.001).

Conclusions

An increasing number of elevated blood biomarkers is associated with higher risks of adverse clinical outcomes following TAVI. The blood multimarker approach may be helpful to enhance risk stratification in TAVI patients.

The Role of Natriuretic Peptides in Predicting Adverse Outcomes After Cardiac Surgery: An Updated Systematic Review

The increasing global burden of cardiovascular disease, particularly, in the aging population, has led to an increase in high-risk cardiac surgical procedures. The current preoperative risk stratification scores, such as the European System for Cardiac Operative Risk Evaluation and the Society for Thoracic Surgeons score, have limitations in their predictive accuracy and tend to underestimate the mortality risk in higher-risk populations. This systematic review aimed to evaluate the utility of natriuretic peptides, brain natriuretic peptide (BNP) and its precursor prohormone (N-terminal prohormone BNP), as predictive biomarkers for adverse outcomes after cardiac surgery. A comprehensive search strategy was performed, and 63 studies involving 40,667 patients who underwent major cardiac operations were included for data extraction. Preoperative levels of BNP and N-terminal prohormone BNP seemed to be associated with an increased risk of short- and long-term mortality, postoperative heart failure, kidney injury, and length of intensive care unit stay. However, their predictive value for postoperative arrhythmias and myocardial infarction was less established. Our findings suggest that natriuretic peptides may play an important role in risk prediction in patients who underwent cardiac surgery. The addition of these biomarkers to the existing clinical risk stratification strategies may enhance their predictive accuracy. However, this needs to be endorsed by data derived from wide-scale clinical trials.

Pathophysiology, emerging techniques for the assessment and novel treatment of aortic stenosis

Our perspectives on aortic stenosis (AS) are changing. Evolving from the traditional thought of a passive degenerative disease, developing a greater understanding of the condition's mechanistic underpinning has shifted the paradigm to an active disease process. This advancement from the 'wear and tear' model is a result of the growing economic and health burden of AS, particularly within industrialised countries, prompting further research. The pathophysiology of calcific AS (CAS) is complex, yet can be characterised similarly to that of atherosclerosis. Progressive remodelling involves lipid-protein complexes, with lipoprotein(a) being of particular interest for diagnostics and potential future treatment options.There is an unmet clinical need for asymptomatic patient management; no pharmacotherapies are proven to slow progression and intervention timing varies. Novel approaches are developing to address this through: (1) screening with circulating biomarkers; (2) development of drugs to slow disease progression and (3) early valve intervention guided by medical imaging. Existing biomarkers (troponin and brain natriuretic peptide) are non-specific, but cost-effective predictors of ventricular dysfunction. In addition, their integration with cardiovascular MRI can provide accurate risk stratification, aiding aortic valve replacement decision making. Currently, invasive intervention is the only treatment for AS. In comparison, the development of lipoprotein(a) lowering therapies could provide an alternative; slowing progression of CAS, preventing left ventricular dysfunction and reducing reliance on surgical intervention.The landscape of AS management is rapidly evolving. This review outlines current understanding of the pathophysiology of AS, its management and future perspectives for the condition's assessment and treatment.

Integrating hemodynamics with ventricular and valvular remodeling in aortic stenosis. A paradigm shift in therapeutic decision making

Aortic valve stenosis (AS) has traditionally been approached in hemodynamic terms. Although hemodynamics and symptoms have formed the basis of recommending interventional treatment in AS, other factors reflecting left ventricular and valvular and/or vascular remodeling are equally important for the prognosis and outcome of patients with AS. Left ventricular and valvular/vascular remodeling in AS do not consistently correlate with hemodynamic severity of AS. Those remodeling changes are reflected and can be detected by a variety of novel laboratory and imaging techniques, including biomarkers, echocardiography, cardiac magnetic resonance and gated Computer Tomography (CT) imaging. Taking all those elements into Heart Team therapeutic decision making in patients with AS, can significantly improve appropriate patient selection for interventional treatment and patient outcomes. We review this novel approach and propose a simple algorithm for decision making by the Heart Team, in patients with moderate or severe AS.

Evaluation of new and old biomarkers in dogs with degenerative mitral valve disease

Background

Dogs with degenerative mitral valve disease are commonly presented to small animal clinicians. Diagnosis, clinical staging, and therapeutic design are based on a combination of clinical examination, radiography, and echocardiography. To support diagnosis and clinical monitoring, a multi-marker-based approach would be conceivable. The aim of this study was to investigate the suitability of Galectin-3 and interleukin-1 receptor-like 1 protein (ST2) in dogs with degenerative mitral valve disease in accordance with N-terminal-prohormone-B-type natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI). For this purpose, serum concentrations of Galectin-3 and ST2 of 64 dogs with different stages of mitral valve disease and 21 dogs without cardiac disease were analyzed at the first examination and six months later. Echocardiography, blood cell count and clinical chemistry were performed and established biomarkers NT-proBNP and cTnI were measured additionally. Differences in the biomarker concentrations between all groups at both timepoints and the change in biomarker concentrations from first to second evaluation was investigated. Furthermore, correlations of each biomarker, between biomarkers and echocardiographic measurements, were calculated. Finally, the receiver-operating characteristic curve and the area under the curve analysis were performed to differentiate between disease stages and controls.

Results

Serum concentrations of Galectin-3 and ST2 were not statistically different between canine patients in the respective stages of mitral valve disease or in comparison to dogs in the control group at any timepoint. A significant increase in ST2 concentrations from the baseline to the follow-up examination was observed in dogs classified as stage B1 and the control group. The concentrations of NT-proBNP and cTnI in stage C dogs were significantly increased in comparison to the other groups.

Conclusions

In this study, no relation between Galectin-3 and ST2 levels to the presence or stage of mitral valve disease could be detected. Nevertheless, considering the increase in ST2 concentrations from the first to second measurement, its value on monitoring disease progress could be feasible. In agreement with previous studies, NT-proBNP and cTnI have once more proven their utility in assessing disease severity. The approach of examining new cardiac biomarkers in dogs is still worth pursuing.

Novel predictive role for mid-regional proadrenomedullin in moderate to severe aortic stenosis

OBJECTIVE

We investigated the prognostic significance of selected known and novel circulating biomarkers in aortic stenosis (AS).

METHODS

N-terminal pro-BNP (NT-proBNP), high-sensitivity troponin-T (hsTnT), growth differentiation factor-15 (GDF-15), suppression of tumorigenicity-2 (ST2), mid-regional proadrenomedullin (MR-proADM) and mid-regional proatrial natriuretic peptide (MR-proANP) were measured in patients with moderate to severe AS, New York Heart Association (NYHA) class I-II and left ventricular ejection fraction ≥50%, recruited consecutively across five centres from 2011 to 2018. Their ability to predict both primary (all-cause mortality, heart failure hospitalisation or progression to NYHA class III-IV) and secondary (additionally incorporating syncope and acute coronary syndrome) outcomes was determined by competing risk analyses.

RESULTS

Among 173 patients with AS (age 69±11 years, 55% male, peak transaortic velocity (Vmax) 4.0±0.8 m/s), the primary and secondary outcomes occurred in 59 (34%) and 66 (38%), respectively. With aortic valve replacement as a competing risk, the primary outcome was determined consistently by the comorbidity index and each selected biomarker except ST2 (p<0.05), independent of NYHA class, Vmax, LV-global longitudinal strain and serum creatinine. MR-proADM had the highest discriminative value for both primary (subdistribution HR (SHR) 11.3, 95% CI 3.9 to 32.7) and secondary outcomes (SHR 12.6, 95% CI 4.7 to 33.5). Prognostic assessment of dual-biomarker combinations identified MR-proADM plus either hsTnT or NT-proBNP as the best predictive model for both clinical outcomes. Paired biomarker models were not superior to those including MR-proADM as the sole circulating biomarker.

CONCLUSION

MR-proADM most powerfully portended worse prognosis and should be further assessed as possibly the biomarker of choice for risk stratification in AS.

Left Ventricular Hypertrophy and Biomarkers of Cardiac Damage and Stress in Aortic Stenosis

Background

Left ventricular hypertrophy (LVH) is associated with increased mortality risk and rehospitalization after transcatheter aortic valve replacement among those with severe aortic stenosis. Whether cardiac troponin (cTnT) and NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) risk stratify patients with aortic stenosis and without LVH is unknown.

Methods and Results

In a multicenter prospective registry of 923 patients with severe aortic stenosis undergoing transcatheter aortic valve replacement, we included 674 with core‐laboratory‐measured LV mass index, cTnT, and NT‐proBNP. LVH was defined by sex‐specific guideline cut‐offs and elevated biomarker levels were based on age and sex cut‐offs. Adjusted Cox proportional hazards models evaluated associations between LVH and biomarkers and all‐cause death out to 5 years. Elevated cTnT and NT‐proBNP were present in 82% and 86% of patients with moderate/severe LVH, respectively, as compared with 66% and 69% of patients with no/mild LVH, respectively (P<0.001 for each). After adjustment, compared with no/mild LVH, moderate/severe LVH was associated with an increased hazard of mortality (adjusted hazard ratio [aHR], 1.34; 95% CI 1.01–1.77, P=0.043). cTnT and NT‐proBNP each risk stratified patients with moderate/severe LVH (P<0.05). In a model with both biomarkers and LVH included, elevated cTnT (aHR, 2.08; 95% CI 1.45–3.00, P<0.001) and elevated NT‐proBNP (aHR, 1.46; 95% CI 1.00–2.11, P=0.049) were each associated with increased mortality risk, whereas moderate/severe LVH was not (P=0.15).

Conclusions

Elevations in circulating cTnT and NT‐proBNP are more common as LVH becomes more pronounced but are also observed in those with no/minimal LVH. As measures of maladaptive remodeling and cardiac injury, cTnT and NT‐proBNP predict post‐transcatheter aortic valve replacement mortality better than LV mass index. These findings may have important implications for risk stratification and treatment of patients with aortic stenosis.

Plasma biomarkers associated with adverse outcomes in patients with calcific aortic stenosis

AIMS

Enhanced risk stratification of patients with aortic stenosis (AS) is necessary to identify patients at high risk for adverse outcomes, and may allow for better management of patient subgroups at high risk of myocardial damage. The objective of this study was to identify plasma biomarkers and multimarker profiles associated with adverse outcomes in AS.

METHODS AND RESULTS

We studied 708 patients with calcific AS and measured 49 biomarkers using a Luminex platform. We studied the correlation between biomarkers and the risk of (i) death and (ii) death or heart failure-related hospital admission (DHFA). We also utilized machine-learning methods (a tree-based pipeline optimizer platform) to develop multimarker models associated with the risk of death and DHFA. In this cohort with a median follow-up of 2.8 years, multiple biomarkers were significantly predictive of death in analyses adjusted for clinical confounders, including tumour necrosis factor (TNF)-α [hazard ratio (HR) 1.28, P < 0.0001], TNF receptor 1 (TNFRSF1A; HR 1.38, P < 0.0001), fibroblast growth factor (FGF)-23 (HR 1.22, P < 0.0001), N-terminal pro B-type natriuretic peptide (NT-proBNP) (HR 1.58, P < 0.0001), matrix metalloproteinase-7 (HR 1.24, P = 0.0002), syndecan-1 (HR 1.27, P = 0.0002), suppression of tumorigenicity-2 (ST2) (IL1RL1; HR 1.22, P = 0.0002), interleukin (IL)-8 (CXCL8; HR 1.22, P = 0.0005), pentraxin (PTX)-3 (HR 1.17, P = 0.001), neutrophil gelatinase-associated lipocalin (LCN2; HR 1.18, P < 0.0001), osteoprotegerin (OPG) (TNFRSF11B; HR 1.26, P = 0.0002), and endostatin (COL18A1; HR 1.28, P = 0.0012). Several biomarkers were also significantly predictive of DHFA in adjusted analyses including FGF-23 (HR 1.36, P < 0.0001), TNF-α (HR 1.26, P < 0.0001), TNFR1 (HR 1.34, P < 0.0001), angiopoietin-2 (HR 1.26, P < 0.0001), syndecan-1 (HR 1.23, P = 0.0006), ST2 (HR 1.27, P < 0.0001), IL-8 (HR 1.18, P = 0.0009), PTX-3 (HR 1.18, P = 0.0002), OPG (HR 1.20, P = 0.0013), and NT-proBNP (HR 1.63, P < 0.0001). Machine-learning multimarker models were strongly associated with adverse outcomes (mean 1-year probability of death of 0%, 2%, and 60%; mean 1-year probability of DHFA of 0%, 4%, 97%; P < 0.0001). In these models, IL-6 (a biomarker of inflammation) and FGF-23 (a biomarker of calcification) emerged as the biomarkers of highest importance.

CONCLUSIONS

Plasma biomarkers are strongly associated with the risk of adverse outcomes in patients with AS. Biomarkers of inflammation and calcification were most strongly related to prognosis.

Cardiac Biomarkers and Prediction of Early Outcome After Heart Valve Surgery: A Prospective Observational Study

OBJECTIVES

Circulating cardiac biomarkers may improve the prediction of long-term outcomes after cardiac surgery. The authors sought to assess if cardiac biomarkers also help better predict short-term morbidity.

DESIGN

Prospective observational study.

SETTING

Single academic hospital.

PARTICIPANTS

A total of 250 patients undergoing aortic or mitral valve surgery with or without associated coronary artery bypass grafts.

INTERVENTION

None MEASUREMENT AND MAIN RESULTS: Relationships between preoperative plasma concentrations of four cardiac biomarkers (sST2, Galectin-3, GDF-15, and NT-proBNP) and postoperative outcome were assessed using logistic regressions and Cox proportional hazards models. The primary outcome was a composite of 30-day mortality, an inotropic support longer than 48 hours and an initial length of stay in the intensive care >five days. Secondary outcome measures were postoperative acute kidney injury, inotropic support duration, lengths of intensive care unit and hospital stays, and 30-day and one-year mortality. No association was observed between any of the four cardiac biomarkers and the primary outcome. The preoperative levels of Galectin-3 (hazard ratio = 1.2; p < 0.001) and sST2 (hazard ratio = 1.01, p < 0.001) were significantly associated with one-year survival, and their addition to the EuroSCORE II significantly improved the prediction of one-year mortality (p < 0.001). Similarly, Galectin-3 was associated with postoperative acute kidney injury (odds ratio = 1.15, p = 0.001) and improved the prediction of this complication when added to the EuroSCORE II (p = 0.002).

CONCLUSIONS

These results suggested that the ability of cardiac biomarkers to predict short-term outcome after cardiac surgery, though of interest, appears limited. Conversely, cardiac biomarkers may have the potential to refine the prediction of long-term outcome. Admittedly, all positive results were obtained on secondary outcomes and must be regarded with caution.

Biomarkers Associated with Mortality in Aortic Stenosis: A Systematic Review and Meta-Analysis

The optimal timing of aortic valve replacement (AVR) remains controversial. Several biomarkers reflect the underlying pathophysiological processes in aortic stenosis (AS) and may be of use as mortality predictors. The aim of this systematic review and meta-analysis is to evaluate the blood biomarkers utilised in AS and assess whether they associate with mortality. PubMed and Embase were searched for studies reporting baseline biomarker level and mortality outcomes in patients with AS. A total of 83 studies met the inclusion criteria and were systematically reviewed. Of these, 21 reporting brain natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), Troponin and Galectin-3 were meta-analysed. Pooled analysis demonstrated that all-cause mortality was significantly associated with elevated baseline levels of BNP (HR 2.59; 95% CI 1.95–3.44; p < 0.00001), NT-proBNP (HR 1.73; 95% CI 1.45–2.06; p = 0.00001), Troponin (HR 1.65; 95% CI 1.31–2.07; p < 0.0001) and Galectin-3 (HR 1.82; 95% CI 1.27–2.61; p < 0.001) compared to lower baseline biomarker levels. Elevated levels of baseline BNP, NT-proBNP, Troponin and Galectin-3 were associated with increased all-cause mortality in a population of patients with AS. Therefore, a change in biomarker level could be considered to refine optimal timing of intervention. The results of this meta-analysis highlight the importance of biomarkers in risk stratification of AS, regardless of symptom status.

Corrected QT Interval in Severe Aortic Stenosis: Clinical and Hemodynamic Correlates and Prognostic Impact

BACKGROUND

The role of the electrocardiogram for risk stratification in patients with severe aortic stenosis is not established. We assessed the hemodynamic correlates and the prognostic value of the corrected QT interval (QTc) in patients with severe aortic stenosis undergoing aortic valve replacement.

METHODS

The QT interval was measured in a 12-lead electrocardiogram in 485 patients (age 74 ± 10 years, 57% male) with severe aortic stenosis (indexed aortic valve area 0.41 ± 0.13 cm²/m², left ventricular ejection fraction 58 ± 12%) the day prior to cardiac catheterization. Prolonged QTc was defined as QTc >450 ms in men and QTc >470 ms in women. The outcome parameter was all-cause mortality.

RESULTS

Patients with prolonged QTc (n = 100; 77 men, 23 women) had similar indexed aortic valve area but larger left ventricular and left atrial size, lower left ventricular ejection fraction, more severe mitral regurgitation, lower cardiac index, and higher mean pulmonary artery pressure, mean pulmonary artery wedge pressure, and pulmonary vascular resistance, as compared with patients with normal QTc (n = 385). After a median follow-up of 3.7 years (interquartile range, 2.6-5.2) after surgical (n = 349) or transcatheter (n = 136) aortic valve replacement, patients with prolonged QTc had higher mortality than those with normal QTc (hazard ratio 2.81 [95% confidence interval, 1.51-5.20]; P < .001). Prolonged QTc was an independent predictor of death along with more severe mitral regurgitation and higher pulmonary vascular resistance.

CONCLUSIONS

In patients with severe aortic stenosis, prolonged QTc is a marker of an advanced disease stage associated with an adverse hemodynamic profile and increased long-term mortality after aortic valve replacement.

Additive prognostic value of carbohydrate antigen-125 over frailty in patients undergoing transcatheter aortic valve replacement

BACKGROUND

To evaluate the additive prognostic value of myocardial, inflammatory, and renal biomarkers according to frailty status in patients undergoing transcatheter aortic valve replacement (TAVR) for aortic stenosis (AS).

METHODS

A total of 111 subjects who underwent TAVR at Hospital Italiano de Buenos Aires, Argentina between January 2016 and December 2018 were retrospectively reviewed. Plasma levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP), high sensitivity troponin T (hs-cTnT), C-reactive protein (CRP), cystatin-c (Cys-C) and carbohydrate antigen-125 (CA-125) were assessed prior to TAVR. Frailty status was assessed according to the fried physical frailty phenotype (FPFP). The primary endpoint was defined as all-cause death and/or readmission for worsening congestive heart failure (CHF) within the first year after TAVR.

RESULTS

Of the 111 patients included, 48/111 (43%) were considered to be "frail" according to the FPFP. Among biomarkers, we found CA-125 to be strongly associated with the primary endpoint (p = .006). CA-125 ≥ 18.2 U/ml was present in 41% and was associated with a higher rate of the primary endpoint (31% vs. 9%; p = .003). After multivariable adjustment, CA-125 ≥ 18.2 U/ml (hazard ratio [HR] 3.17; p = .024) was the only independent predictor of the primary endpoint. Finally, the inclusion of CA-125 to frailty significantly improved C-index (0.68-0.74; p < .05), and provided a Net Reclassification Improvement (NRI) of 0.34 (95% CI 0.19-0.49, p = .031), largely through reductions in risk estimates among pre-frail and frail patients.

CONCLUSIONS

CA-125, a tumor biomarker, outperformed frailty for predicting the primary endpoint within the first year after TAVR.

Association of Natriuretic Peptide Levels After Transcatheter Aortic Valve Replacement With Subsequent Clinical Outcomes

Importance

Among those with aortic stenosis, natriuretic peptide levels can provide risk stratification, predict symptom onset, and aid decisions regarding the timing of valve replacement. Less is known about the prognostic significance and potential clinical utility of natriuretic peptide levels measured after valve replacement.

Objective

To determine the associations of elevated B-type natriuretic peptide (BNP) levels after transcatheter aortic valve replacement (TAVR) and change in BNP levels between follow-up time points with risk of subsequent clinical outcomes.

Design, Setting, and Participants

In this cohort study, patients with severe symptomatic aortic stenosis at intermediate, high, or prohibitive surgical risk for aortic valve replacement who underwent TAVR from the PARTNER IIA cohort, PARTNER IIB cohort, SAPIEN 3 intermediate-risk registry, and SAPIEN 3 high-risk registry were included. B-type natriuretic peptide levels were obtained at baseline and discharge as well as 30 days and 1 year after TAVR. For each measurement, a BNP ratio was calculated using measured BNP level divided by the upper limit of normal for the assay used. Outcomes were evaluated in landmark analyses out to 2 years. Data were collected from April 2011 to January 2019.

Main Outcomes and Measures

All-cause death, cardiovascular death, rehospitalization, and the combined end point of cardiovascular death or rehospitalization.

Results

Among 3391 included patients, 1969 (58.1%) were male, and the mean (SD) age was 82 (7.5) years. Most patients had a BNP ratio greater than 1 at each follow-up time point, including 2820 of 3256 (86.6%) at baseline, 2652 of 2995 (88.5%) at discharge, 1779 of 2209 (80.5%) at 30 days, and 1799 of 2391 (75.2%) at 1 year. After adjustment, every 1-point increase in BNP ratio at 30 days (approximately equivalent to an increase of 100 pg/mL in BNP) was associated with an increased hazard of all-cause death (adjusted hazard ratio [aHR], 1.11; 95% CI, 1.07-1.15), cardiovascular death (aHR, 1.16; 95% CI, 1.11-1.21), and rehospitalization (aHR, 1.08; 95% CI, 1.03-1.14) between 30 days and 2 years. Among those with a BNP ratio of 2 or more at discharge, after adjustment, every 1-point decrease in BNP ratio between discharge and 30 days was associated with a decreased hazard of all-cause death (aHR, 0.92; 95% CI, 0.88-0.96) between 30 days and 2 years.

Conclusions and Relevance

Elevated BNP levels after TAVR was independently associated with increased subsequent mortality and rehospitalizations. Further studies to determine how best to mitigate this risk are warranted.

Timing of intervention in asymptomatic patients with valvular heart disease

Current management of valvular heart disease (VHD) seeks to optimize long-term outcome by timely intervention. Recommendations for treatment of patients with symptoms due to severe valvular disease are based on a foundation of solid evidence. However, when to intervene in asymptomatic patients remains controversial and decision requires careful individual weighing of the potential benefits against the risk of intervention and its long-term consequences. The primary rationale for earlier intervention is prevention of irreversible left ventricular (LV) myocardial changes that might result in later clinical symptoms and adverse cardiac events. A number of outcome predictors have been identified that facilitate decision-making. This review summarizes current recommendations and discusses recently published data that challenge them suggesting even earlier intervention. In adults with asymptomatic aortic stenosis (AS), emerging risk markers include very severe valve obstruction, elevated serum natriuretic peptide levels, and imaging evidence of myocardial fibrosis or increased extracellular myocardial volume. Currently, transcatheter aortic valve implantation (TAVI) is not recommended for treatment of asymptomatic severe AS although this may change in the future. In patients with aortic regurgitation (AR), the potential benefit of early intervention in preventing LV dilation and dysfunction must be balanced against the long-term risk of a prosthetic valve, a particular concern because severe AR often occurs in younger patients with a congenital bicuspid valve. In patients with mitral stenosis, the option of transcatheter mitral balloon valvotomy tilts the balance towards earlier intervention to prevent atrial fibrillation, embolic events, and pulmonary hypertension. When chronic severe mitral regurgitation is due to mitral valve prolapse, anatomic features consistent with a high likelihood of a successful and durable valve repair favour early intervention. The optimal timing of intervention in adults with VHD is a constantly changing threshold that depends not only on the severity of valve disease but also on the safety, efficacy, and long-term durability of our treatment options.

Urea level is an independent predictor of mortality in patients with severe aortic valve stenosis

Introduction

Severe aortic stenosis (AS) is the most common valvular heart disease in the western world. Various factors are related to severe AS prognosis, including chronic kidney disease. The aim of this study was to evaluate the prognostic value of urea level in patients with severe AS.

Methods

We prospectively enrolled 142 patients (79.1±9.4 years, 88 women) with severe AS (mean valve area 0.67± 0.17 cm²). Clinical assessment, blood tests and echocardiography were performed at enrollment and follow up. The patient population was divided into low and high urea level groups, according to the median urea level at enrollment (72 patients, mean urea 35.5±6.2 mg/dL and 70 patients, mean urea 61.1±17.8 mg/dL, respectively). Hundred and twelve patients (79%) underwent aortic valve intervention. The primary endpoint was all-cause and cardiovascular mortality.

Outcomes

During follow-up of 37±19.5 months, 56 (37.1%) patients died, 39 due to cardiovascular causes. In univariate analysis, age, urea level, creatinine, New York Heart Association (NYHA) class and aortic valve intervention were associated with all-cause mortality. However, in multivariate analysis only aortic valve intervention and blood urea were independent predictors of all-cause mortality (HR 0.494; 95% CI 0.226–0.918, P = 0.026 and HR 1.015; 95% CI 1.003–1.029, P = 0.046 respectively). Urea level, NYHA class and age were also significant predictors of cardiovascular mortality. Whereas, in multivariate analysis, only urea level predicted cardiovascular mortality in these patients (HR 1.017; CI 1.003–1.031 P = 0.019).

Conclusions

Blood urea, a generally readily available and routinely determined marker of renal function, is an independent prognostic factor in patients with severe AS.