A clinical risk score of myocardial fibrosis predicts adverse outcomes in aortic stenosis.

AIMS: Midwall myocardial fibrosis on cardiovascular magnetic resonance (CMR) is a marker of early ventricular decompensation and adverse outcomes in aortic stenosis (AS). We aimed to develop and validate a novel clinical score using variables associated with midwall fibrosis. METHODS AND RESULTS: One hundred forty-seven patients (peak aortic velocity (Vmax) 3.9 [3.2,4.4] m/s) underwent CMR to determine midwall fibrosis (CMR cohort). Routine clinical variables that demonstrated significant association with midwall fibrosis were included in a multivariate logistic score. We validated the prognostic value of the score in two separate outcome cohorts of asymptomatic patients (internal: n = 127, follow-up 10.3 [5.7,11.2] years; external: n = 289, follow-up 2.6 [1.6,4.5] years). Primary outcome was a composite of AS-related events (cardiovascular death, heart failure, and new angina, dyspnoea, or syncope). The final score consisted of age, sex, Vmax, high-sensitivity troponin I concentration, and electrocardiographic strain pattern [c-statistic 0.85 (95% confidence interval 0.78-0.91), P < 0.001; Hosmer-Lemeshow χ(2) = 7.33, P = 0.50]. Patients in the outcome cohorts were classified according to the sensitivity and specificity of this score (both at 98%): low risk (probability score <7%), intermediate risk (7-57%), and high risk (>57%). In the internal outcome cohort, AS-related event rates were >10-fold higher in high-risk patients compared with those at low risk (23.9 vs. 2.1 events/100 patient-years, respectively; log rank P < 0.001). Similar findings were observed in the external outcome cohort (31.6 vs. 4.6 events/100 patient-years, respectively; log rank P < 0.001). CONCLUSION: We propose a clinical score that predicts adverse outcomes in asymptomatic AS patients and potentially identifies high-risk patients who may benefit from early valve replacement.

Epicardial adipose tissue volume is associated with left ventricular remodelling in calcific aortic valve stenosis.

BACKGROUND: The severity of left ventricular (LV) remodelling is only partially related to the severity of aortic valve stenosis; additional factors, including diabetes, insulin resistance, obesity and metabolic syndrome, may play important roles. Epicardial adipose tissue (EAT), now considered as a metabolically active organ, is also linked to these factors. AIM: To analyse the association between EAT volume measured using computed tomography and LV remodelling in a prospective cohort of patients with aortic stenosis. METHODS: Consecutive asymptomatic patients with at least mild degenerative aortic stenosis enrolled in a prospective cohort that aimed to assess the determinants of aortic stenosis occurrence and progression constituted our population. RESULTS: We enrolled 143 patients (78±5 years; 65% men). Mean LV mass and EAT volume were 219±64g and 134±56mL, respectively. LV hypertrophy was diagnosed in 86 patients (60%), and concentric hypertrophy (32%) was the main remodelling pattern. EAT was associated with body mass index (P<0.001) and body surface area (P<0.001), but not with age (P=0.33) or aortic stenosis severity (all P>0.10). EAT was correlated with LV mass (r=0.41; P<0.0001), and after adjustment for age, sex, body mass index/body surface area, hypertension, waist circumference, low-density lipoprotein cholesterol and aortic stenosis severity, EAT was independently associated with LV mass (P=0.01/P=0.02). Similar results were found when EAT and LV mass index (adjusted for body surface area) were considered instead of absolute values (P=0.04). CONCLUSIONS: In this prospective cohort of patients with aortic stenosis, EAT volume was independently associated with LV mass. Further studies are warranted to elucidate the underlying mechanisms of this link.

Ascending aorta dilatation rates in patients with tricuspid and bicuspid aortic stenosis: the COFRASA/GENERAC study.

Background: Ascending aorta (AA) dilatation is common in aortic valve stenosis (AS) but data regarding AA progression, its determinants and impact of valve anatomy [bicuspid (BAV), or tricuspid (TAV)] are scarce. Methods and Results: Asymptomatic AS patients enrolled in a prospective cohort (COFRASA/GENERAC) with at least 2 years of follow-up were considered in the present analysis. A transthoracic echocardiography (TTE) and a computed tomography (CT) scan were performed at inclusion and yearly thereafter. We enrolled 195 patients [mean gradient 22 ± 11 mmHg, 42 BAV patients (22%)]. Mean aorta diameters assessed using TTE were 35 ± 4 and 36 ± 5 mm at the sinuses of Valsalva and tubular level, respectively. Ascending aorta diameter was >40 mm in 29% of patients (24% in TAV vs. 52% in BAV, P < 0.01). Determinants of AA diameters were age, sex, BSA, and BAV, but not AS severity. After a mean follow-up of 3.8 ± 1.5years, AA enlargement rate assessed using TTE was +0.18 ± 0.34 mm/year and +0.36 ± 0.54 mm/year at the Valsalva and tubular level, respectively. Determinants of the progression of AA size were smaller AA diameter (P < 0.01) but not baseline AS severity or valve anatomy (all P > 0.05). Only four patients presented an AA progression ≥2 mm/year. Correlations between TTE and CT scan were excellent (all r >0.74) and similar results were obtained using CT. During follow-up, two BAV patients underwent a combined AA surgery; no surgery was primarily performed for AA aneurysm and no dissection was observed. Conclusion: In this prospective cohort of AS patients determinants of AA diameters were age, sex, BSA, and valve anatomy but not AS severity. AA progression rates were low and not influenced by AS severity or valve anatomy.

Computed Tomography Aortic Valve Calcium Scoring in Patients With Aortic Stenosis.

BACKGROUND: Computed tomography aortic valve calcium scoring (CT-AVC) holds promise for the assessment of patients with aortic stenosis (AS). We sought to establish the clinical utility of CT-AVC in an international multicenter cohort of patients. METHODS AND RESULTS: Patients with AS who underwent ECG-gated CT-AVC within 3 months of echocardiography were entered into an international, multicenter, observational registry. Optimal CT-AVC thresholds for diagnosing severe AS were determined in patients with concordant echocardiographic assessments, before being used to arbitrate disease severity in those with discordant measurements. In patients with long-term follow-up, we assessed whether CT-AVC thresholds predicted aortic valve replacement and death. In 918 patients from 8 centers (age, 77±10 years; 60% men; peak velocity, 3.88±0.90 m/s), 708 (77%) patients had concordant echocardiographic assessments, in whom CT-AVC provided excellent discrimination for severe AS (C statistic: women 0.92, men 0.89). Our optimal sex-specific CT-AVC thresholds (women 1377 Agatston unit and men 2062 Agatston unit) were nearly identical to those previously reported (women 1274 Agatston unit and men 2065 Agatston unit). Clinical outcomes were available in 215 patients (follow-up 1029 [126-2251] days). Sex-specific CT-AVC thresholds independently predicted aortic valve replacement and death (hazard ratio, 3.90 [95% confidence interval, 2.19-6.78]; P<0.001) after adjustment for age, sex, peak velocity, and aortic valve area. Among 210 (23%) patients with discordant echocardiographic assessments, there was considerable heterogeneity in CT-AVC scores, which again were an independent predictor of clinical outcomes (hazard ratio, 3.67 [95% confidence interval, 1.39-9.73]; P=0.010). CONCLUSIONS: Sex-specific CT-AVC thresholds accurately identify severe AS and provide powerful prognostic information. These findings support their integration into routine clinical practice. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01358513, NCT02132026, NCT00338676, NCT00647088, NCT01679431.

Influence of metabolic syndrome and diabetes on progression of calcific aortic valve stenosis.

BACKGROUND: Determinants of the progression of aortic stenosis (AS) remained unclear. Metabolic syndrome (MetS) and diabetes are suspected to play an active role but literature is scarce and results conflicting. We sought to assess their impact in an ongoing prospective cohort of asymptomatic patients with at least mild AS. METHODS: We enrolled 203 patients (73±9years, 75% men) with at least 2years of follow-up. Risk-factors assessment was performed at baseline. Annual progression was calculated as [(final-baseline measurements)/follow-up duration] for both mean pressure gradient (MPG) and degree of aortic valve calcification (AVC) measurements. RESULTS: Ninety-nine patients (49%) had MetS and 50 (25%) had diabetes (including 39 with MetS). After a mean follow-up of 3.2±1.2years, AS progression was not different between patients with and without MetS either using MPG (+3±3 vs. +4±4mmHg/year, p=0.25) or AVC (+211±231 vs. +225±222AU/year, p=0.75). Same results were obtained for patients with diabetes (3±3 vs. 4±4mmHg/year p=0.53, 187±140 vs. 229±248AU/year p=0.99). MetS had no impact on AS progression in all tested subgroups based on age, statin prescription, valve anatomy and AS severity (all p≥0.10). CONCLUSION: In our prospective cohort of AS patients, we found no impact of MetS or diabetes on AS progression. Although MetS and diabetes should be actively treated, no impact on AS progression should be expected. Our results support the theory that if cardiovascular risk-factors may play a role at the early phase of AS disease they have no or limited influence on AS progression.

Determinants and prognostic value of Galectin-3 in patients with aortic valve stenosis.

OBJECTIVE: Myocardial fibrosis has been proposed as an outcome predictor in asymptomatic patients with severe aortic stenosis (AS) that may lead to consider prophylactic surgery. It can be detected using MRI but its widespread use is limited and development of substitute biomarkers is highly desirable. We analysed the determinants and prognostic value of galectin-3, one promising biomarker linked to myocardial fibrosis. METHODS: Patients with at least mild degenerative AS enrolled between 2006 and 2013 in two ongoing studies, COFRASA/GENERAC (COhorte Française de Rétrécissement Aortique du Sujet Agé/GENEtique du Rétrécissement Aortique), aiming at assessing the determinants of AS occurrence and progression, constituted our population. RESULTS: We prospectively enrolled 583 patients. The mean galectin-3 value was 14.3±5.6 ng/mL. There was no association between galectin-3 and functional status (p=0.55) or AS severity (p=0.58). Independent determinants of galectin-3 were age (p=0.0008), female gender (p=0.04), hypertension (p=0.002), diabetes (p=0.02), reduced left ventricular ejection fraction (p=0.01), diastolic dysfunction (E/e', p=0.02) and creatinine clearance (p<0.0001). Among 330 asymptomatic patients at baseline, galectin-3 was neither predictive of outcome in univariate analysis (p=0.73), nor after adjustment for age, gender, rhythm, creatinine clearance and AS severity (p=0.66). CONCLUSIONS: In a prospective cohort of patients with a wide range of AS severity, galectin-3 was not associated with AS severity or functional status. Main determinants of galectin-3 were age, hypertension and renal function. Galectin-3 did not provide prognostic information on the occurrence of AS-related events. Our results do not support the use of galectin-3 in the decision-making process of asymptomatic patients with AS. TRIAL REGISTRATION NUMBER: COFRASA NCT00338676 and GENERAC CT00647088.