Heterogeneity of systolic dysfunction in patients with severe aortic stenosis and preserved ejection fraction.

BACKGROUND AND AIM: Left ventricular (LV) systolic strain has been shown to be an early marker of LV dysfunction in patients with severe aortic stenosis (AS) despite preserved ejection fraction (EF). Echocardiography has provided useful data on regional LV strain patterns, but is not as sensitive as magnetic resonance imaging (MRI). No prior studies have used MRI-based strain analysis to characterize regional three-dimensional strain in patients with severe AS. METHODS: Twelve patients with severe AS and preserved EF underwent MRI-based multiparametric strain analysis. Circumferential and longitudinal strain values were calculated at individual points throughout the LV and analyzed in 12 discrete regions. Strain values were compared to a database of normal controls. RESULTS: Compared to control patients, circumferential strain in AS patients was significantly reduced at the base (P = 0.002), mid (P = 0.042), and inferior walls (P < 0.001). Longitudinal strain was significantly reduced at the base (P < 0.001), mid (P < 0.001), anterior (P < 0.001), and septal (P < 0.001) walls. Among patients with AS, there was heterogeneity in the location and severity of abnormalities in circumferential and longitudinal strains despite the presence of a preserved EF and lack of prior myocardial infarction. CONCLUSIONS: LV systolic strain is significantly impaired in patients with AS and preserved EF compared to healthy volunteers. Abnormalities in circumferential and longitudinal strains were heterogeneously distributed across the LV of patients with AS, allowing us to identify sentinel regions that may reflect the earliest signs of developing LV dysfunction.

Associations of Sarcopenia and Body Composition Measures With Mortality After Transcatheter Aortic Valve Replacement.

BACKGROUND: Frailty associates with worse outcomes after transcatheter aortic valve replacement (TAVR). Sarcopenia underlies frailty, but the association between a comprehensive assessment of sarcopenia-muscle mass, strength, and performance-and outcomes after TAVR has not been examined. METHODS: From a multicenter prospective registry of patients with symptomatic severe aortic stenosis undergoing TAVR, 445 who had a preprocedure computed tomography and clinical assessment of frailty were included. Cross-sectional muscle (psoas and paraspinal) areas were measured on computed tomography and indexed to height. Gait speed and handgrip strength were obtained, and patients were dichotomized into fast versus slow; strong versus weak; and normal versus low muscle mass. As measures of body composition, cross-sectional fat (subcutaneous and visceral) was measured and indexed to height. RESULTS: The frequency of patients who were slow, weak, and had low muscle mass was 56%, 59%, and 42%, respectively. Among the 3 components of sarcopenia, only slower gait speed (muscle performance) was independently associated with increased post-TAVR mortality (adjusted hazard ratio, 1.12 per 0.1 m/s decrease [95% CI, 1.04-1.21]; P=0.004; adjusted hazard ratio, 1.38 per 1 SD decrease [95% CI, 1.11-1.72]; P=0.004). Meeting multiple sarcopenia criteria was not associated with higher mortality risk than fewer. Lower indexed visceral fat area (adjusted hazard ratio, 1.48 per 1 SD decrease [95% CI, 1.15-1.89]; P=0.002) was associated with mortality but indexed subcutaneous fat was not. Death occurred in 169 (38%) patients. CONCLUSIONS: Among patients with symptomatic severe aortic stenosis and comprehensive sarcopenia and body composition phenotyping, gait speed was the only sarcopenia measure associated with post-TAVR mortality. Lower visceral fat was also associated with increased risk pointing to an obesity paradox also observed in other patient populations. These findings reinforce the clinical utility of gait speed as a measure of risk and a potential target for adjunctive interventions alongside TAVR to optimize clinical outcomes.

Association of Depression and Cognitive Dysfunction With Patient-Centered Outcomes After Transcatheter Aortic Valve Replacement.

BACKGROUND: Depression and cognitive dysfunction (CD) are not routinely screened for in patients before transcatheter aortic valve replacement (TAVR) and their association with postprocedural outcomes is poorly understood. The objectives of this study are to determine the prevalence of depression and CD in patients with aortic stenosis undergoing TAVR and evaluate their association with mortality and quality of life. METHODS: We analyzed a prospective, multicenter TAVR registry that systematically screened patients for preexisting depression and CD with the Patient Health Questionnaire-2 and Mini-Cog, respectively. The associations with mortality were assessed with Cox proportional hazard models and quality of life (Kansas City Cardiomyopathy Questionnaire and EuroQol visual analogue scale) were evaluated using multivariable ordinal regression models. RESULTS: A total of 884 patients were included; median follow-up was 2.88 years (interquartile range=1.2-3.7). At baseline, depression was observed in 19.6% and CD in 31.8%. In separate models, after adjustment, depression (HR, 1.45 [95% CI, 1.13-1.86]; P<0.01) and CD (HR, 1.27 [95% CI, 1.02-1.59]; P=0.04) were each associated with increased mortality. Combining depression and CD into a single model, mortality was greatest among those with both depression and CD (n=62; HR, 2.06 [CI, 1.44-2.96]; P<0.01). After adjustment, depression was associated with 6.6 (0.3-13.6) points lower on the Kansas City Cardiomyopathy Questionnaire 1-year post-TAVR and 6.7 (0.5-12.7) points lower on the EuroQol visual analogue scale. CD was only associated with lower EuroQol visual analogue scale. CONCLUSIONS: Depression and CD are common in patients that undergo TAVR and are associated with increased mortality and worse quality of life. Depression may be a modifiable therapeutic target to improve outcomes after TAVR.

Metabolic Signatures of Cardiac Dysfunction, Multimorbidity, and Post-Transcatheter Aortic Valve Implantation Death.

Background Studies in mice and small patient subsets implicate metabolic dysfunction in cardiac remodeling in aortic stenosis, but no large comprehensive studies of human metabolism in aortic stenosis with long-term follow-up and characterization currently exist. Methods and Results Within a multicenter prospective cohort study, we used principal components analysis to summarize 12 echocardiographic measures of left ventricular structure and function pre-transcatheter aortic valve implantation in 519 subjects (derivation). We used least absolute shrinkage and selection operator regression across 221 metabolites to define metabolic signatures for each structural pattern and measured their relation to death and multimorbidity in the original cohort and up to 2 validation cohorts (N=543 for overall validation). In the derivation cohort (519 individuals; median age, 84 years, 45% women, 95% White individuals), we identified 3 axes of left ventricular remodeling, broadly specifying systolic function, diastolic function, and chamber volumes. Metabolite signatures of each axis specified both known and novel pathways in hypertrophy and cardiac dysfunction. Over a median of 3.1 years (205 deaths), a metabolite score for diastolic function was independently associated with post-transcatheter aortic valve implantation death (adjusted hazard ratio per 1 SD increase in score, 1.54 [95% CI, 1.25-1.90]; P<0.001), with similar effects in each validation cohort. This metabolite score of diastolic function was simultaneously associated with measures of multimorbidity, suggesting a metabolic link between cardiac and noncardiac state in aortic stenosis. Conclusions Metabolite profiles of cardiac structure identify individuals at high risk for death following transcatheter aortic valve implantation and concurrent multimorbidity. These results call for efforts to address potentially reversible metabolic biology associated with risk to optimize post-transcatheter aortic valve implantation recovery, rehabilitation, and survival.

Relation of Subacute Kidney Injury to Mortality After Transcatheter Aortic Valve Implantation.

Acute kidney injury after transcatheter aortic valve implantation (TAVI) has been associated with adverse outcomes; however, data are limited on the subacute changes in renal function that occur after discharge and their impact on clinical outcomes. This study investigates the relation between subacute changes in kidney function at 30 days after TAVI and survival. Patients from 2 centers who underwent TAVI and survived beyond 30 days with baseline, in-hospital, and 30-day measures of renal function were retrospectively analyzed. Patients were stratified based on change in estimated glomerular filtration rate (eGFR) from baseline to 30 days as follows: improved (≥15% higher than baseline), worsened (≤15% lower), or unchanged (values in between). Univariable and multivariable models were constructed to identify predictors of subacute changes in renal function and of 2-year mortality. Of the 492 patients who met inclusion criteria, eGFR worsened in 102 (22%), improved in 110 (22%), and was unchanged in 280 (56%). AKI occurred in 90 patients (18%) and in only 27% of patients with worsened eGFR at 30 days. After statistical adjustment, worsened eGFR at 30 days (hazard ratio vs unchanged eGFR 2.09, 95% CI 1.37 to 3.19, p <0.001) was associated with worse survival, whereas improvement in renal function was not associated with survival (hazard ratio vs unchanged eGFR 1.30, 95% CI 0.79 to 2.11, p = 0.30). Worsened renal function at 30 days after TAVI is associated with increased mortality after TAVI. In conclusion, monitoring renal function after discharge may identify patients at high risk of adverse outcomes.

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.

Global Longitudinal Strain and Biomarkers of Cardiac Damage and Stress as Predictors of Outcomes After Transcatheter Aortic Valve Implantation.

Background Global longitudinal strain (GLS) is a sensitive measure of left ventricular function and a risk marker in severe aortic stenosis. We sought to determine whether biomarkers of cardiac damage (cardiac troponin) and stress (NT-proBNP [N-terminal pro-B-type natriuretic peptide]) could complement GLS to identify patients with severe aortic stenosis at highest risk. Methods and Results From a multicenter prospective cohort of patients with symptomatic severe aortic stenosis who underwent transcatheter aortic valve implantation, we measured absolute GLS (aGLS), cardiac troponin, and NT-proBNP at baseline in 499 patients. Left ventricular ejection fraction <50% was observed in 19% and impaired GLS (aGLS <15%) in 38%. Elevations in cardiac troponin and NT-proBNP were present in 79% and 89% of those with impaired GLS, respectively, as compared with 63% and 60% of those with normal GLS, respectively (P<0.001 for each). aGLS <15% was associated with increased mortality in univariable analysis (P=0.009), but, in a model with both biomarkers, aGLS, and clinical covariates included, aGLS was not associated with mortality; elevation in each biomarker was associated with an increased hazard of mortality (adjusted hazard ratio, >2; P≤0.002 for each) when the other biomarker was elevated, but not when the other biomarker was normal (interaction P=0.015). Conclusions Among patients with symptomatic severe aortic stenosis undergoing transcatheter aortic valve implantation, elevations in circulating cardiac troponin and NT-proBNP are more common as GLS worsens. Biomarkers of cardiac damage and stress are independently associated with mortality after transcatheter aortic valve implantation, whereas GLS is not. These findings may have implications for risk stratification of asymptomatic patients to determine optimal timing of valve replacement.

Preoperative pulmonary function tests predict mortality after surgical or transcatheter aortic valve replacement.

OBJECTIVES: To determine the role of preoperative pulmonary function tests (PFTs) in patients with aortic stenosis (AS) evaluated for aortic valve replacement (AVR), and to evaluate the association between lung disease and mortality in specific subgroups. METHODS: Between 2008 and 2013, 535 patients with preoperative PFTs underwent AVR (transcatheter AVR [TAVR], n = 246; surgical AVR [SAVR], n = 289). The severity of lung disease determined by the Society of Thoracic Surgeons (STS) definition was evaluated in those with and without a clinical suspicion for lung disease (smoking, inhaled steroids/bronchodilators, or home oxygen). The association between lung disease and 1-year mortality was evaluated. RESULTS: Of the 186 patients (35%) without suspected lung disease, 39 (21%) had moderate/severe lung disease by PFT analysis. Among all patients, 1-year mortality was 12% in those with no lung disease, 17% in those with no mild lung disease, 22% in those with moderate lung disease, and 31% in those with severe lung disease (P < .001, log-rank test). After adjustment, moderate/severe lung disease was associated with increased 1-year mortality (adjusted hazard ratio, 2.07; 95% confidence interval, 1.30-3.29; P = .002); this association was not altered by smoking history, suspicion of lung disease, New York Heart Association class, or AVR type (interaction P value nonsignificant for all). CONCLUSIONS: In patients with AS evaluated for AVR, the STS risk score is significantly influenced by the severity of lung disease, which is determined predominantly by PFT results. Even when lung disease is not suspected, PFTs are abnormal in many patients undergoing AVR. Moderate/severe lung disease, diagnosed predominantly by PFTs, is an independent predictor of mortality after SAVR or TAVR. Collectively, these findings suggest that PFTs should be a routine part of the risk stratification of patients considered for AVR.

Systemic inflammatory response syndrome after transcatheter or surgical aortic valve replacement.

OBJECTIVE: An inflammatory response after cardiac surgery is associated with worse clinical outcomes, but recent trials to attenuate it have been neutral. We evaluated the association between systemic inflammatory response syndrome (SIRS) and mortality after transcatheter (TAVR) and surgical aortic valve replacement (SAVR) for aortic stenosis (AS) and evaluated whether diabetes influenced this relationship. METHODS: Patients (n=747) with severe AS treated with TAVR (n=264) or SAVR (n=483) between January 2008 and December 2013 were included and 37% had diabetes mellitus. SIRS was defined by four criteria 12-48 h after aortic valve replacement (AVR): (1) white blood cell count <4 or >12; (2) heart rate >90; (3) temperature <36 or >38°C; or (4) respiratory rate >20. Severe SIRS was defined as meeting all four criteria. The primary endpoint was 6-month all-cause mortality (60 deaths occurred by 6 months). Inverse probability weighting (IPW) was performed on 44 baseline and procedural variables to minimise confounding. RESULTS: Severe SIRS developed in 6% of TAVR patients and 11% of SAVR patients (p=0.02). Six-month mortality tended to be higher in those with severe SIRS (15.5%) versus those without (7.4%) (p=0.07). After adjustment, severe SIRS was associated with higher 6-month mortality (IPW adjusted HR 2.77, 95% CI 2.04 to 3.76, p<0.001). Moreover, severe SIRS was more strongly associated with increased mortality in diabetic (IPW adjusted HR 4.12, 95% CI 2.69 to 6.31, p<0.001) than non-diabetic patients (IPW adjusted HR 1.74, 95% CI 1.10 to 2.73, p=0.02) (interaction p=0.007). The adverse effect of severe SIRS on mortality was similar after TAVR and SAVR. CONCLUSIONS: Severe SIRS was associated with a higher mortality after SAVR or TAVR. It occurred more commonly after SAVR and had a greater effect on mortality in diabetic patients. These findings may have implications for treatment decisions in patients with AS, may help explain differences in outcomes between different AVR approaches and identify diabetic patients as a high-risk subgroup to target in clinical trials with therapies to attenuate SIRS.

Prognostic utility of novel biomarkers of cardiovascular stress in patients with aortic stenosis undergoing valve replacement.

OBJECTIVE: In heart failure populations without aortic stenosis (AS), the prognostic utility of multiple biomarkers in addition to clinical factors has been demonstrated. We aimed to determine whether multiple biomarkers of cardiovascular stress are associated with mortality in patients with AS undergoing aortic valve replacement (AVR) independent of clinical factors. METHODS: From a prospective registry of patients with AS, 345 participants who were referred for and treated with AVR (transcatheter (n=183) or surgical (n=162)) were included. Eight biomarkers were measured on blood samples obtained prior to AVR: growth differentiation factor 15 (GDF15), soluble ST2 (sST2), amino-terminal pro-B-type natriuretic peptide (NTproBNP), galectin-3, high-sensitivity cardiac troponin T, myeloperoxidase, high-sensitivity C reactive protein and monocyte chemotactic protein-1. Biomarkers were evaluated based on median value (high vs low) in a Cox proportional hazards model for all-cause mortality and a parsimonious group of biomarkers selected. Mean follow-up was 1.9±1.2 years; 91 patients died. RESULTS: Three biomarkers (GDF15, sST2 and NTproBNP) were retained in the model. One-year mortality was 5%, 12%, 18% and 33% for patients with 0 (n=79), 1 (n=96), 2 (n=87) and 3 (n=83) biomarkers elevated, respectively (p<0.001). After adjustment for the Society of Thoracic Surgeons (STS) risk score, a greater number of elevated biomarkers was associated with increased mortality (referent: 0 elevated): 1 elevated (HR 1.47, 95% CI 0.60 to 3.63, p=0.40), 2 elevated (HR 2.89, 95% CI 1.24 to 6.74, p=0.014) and 3 elevated (HR 4.59, 95% CI 1.97 to 10.71, p<0.001). Among patients at intermediate or high surgical risk (STS score ≥4), 1-year and 2-year mortality rates were 34% and 43% for patients with three biomarkers elevated versus 4% and 4% for patients with 0 biomarkers elevated. When added to the STS score, the number of biomarkers elevated provided a category-free net reclassification improvement of 64% at 1 year (p<0.001). The association between a greater number of elevated biomarkers and increased mortality after valve replacement was similar in the transcatheter and surgical AVR populations. CONCLUSIONS: These findings demonstrate the potential utility of multiple biomarkers to aid in risk stratification of patients with AS. Further studies are needed to evaluate their utility in clinical decision-making in specific AS populations.