Long-term mortality after isolated coronary artery bypass grafting and risk factors for mortality.

BACKGROUND: Patients requiring coronary artery bypass grafting (CABG) have multiple co-morbidities which need to be considered in totality when determining surgical risks. The objective of this study is to evaluate short-term and long-term mortality rates of CABG surgery, as well as to identify the most significant risk factors for mortality after isolated CABG. METHODS: All patients with complete dataset who underwent isolated CABG between January 2008 and December 2017 were included. Univariate and multivariate Cox regression was performed to determine the risk factors for all-cause mortality. Classification and regression tree analysis was performed to identify the relative importance of these risk factors. RESULTS: 3,573 patients were included in the study. Overall mortality rate was 25.7%. In-hospital mortality rate was 1.62% overall. 30-day, 1-year, 5-year, 10-year and 14.5-year mortality rates were 1.46%, 2.94%, 9.89%, 22.79% and 36.30% respectively. Factors associated with death after adjustment for other risk factors were older age, lower body mass index (BMI), hypertension, diabetes mellitus, chronic obstructive pulmonary disease, pre-operative renal failure on dialysis, higher last pre-operative creatinine level, lower estimated glomerular filtration rate (eGFR), heart failure, lower left ventricular ejection fraction and New York Heart Association class II, III and IV. Additionally, female gender and logistic EuroSCORE were associated with death on univariate Cox analysis, but not associated with death after adjustment with multivariate Cox analysis. Using CART analysis, the strongest predictor of mortality was pre-operative eGFR < 46.9, followed by logistic EuroSCORE ≥ 2.4. CONCLUSION: Poorer renal function, quantified by a lower eGFR, is the best predictor of post-CABG mortality. Amongst other risk factors, logistic EuroSCORE, age, diabetes and BMI had a relatively greater impact on mortality. Patients with chronic kidney disease stage 3B and above are at highest risk for mortality. We hope these findings heighten awareness to optimise current medical therapy in preserving renal function upon diagnosis of any atherosclerotic disease and risk factors contributing to coronary artery disease.

Factors Affecting Rate of Progression of Aortic Stenosis and Its Impact on Outcomes.

The rate of aortic stenosis (AS) progression in patients with moderate AS is unclear. This study examined the risk factors of progression from moderate to severe AS and its impact on clinical outcomes. A total of 954 patients with moderate AS (valve area >1.0 and ≤1.5 cm²) and follow-up echocardiograms were included. AS progressed to severe (valve area <1.0 cm1) in 589 patients (61.7%) over a median follow-up of 2.46 (interquartile range [IQR] 1.29 to 3.91) years. Of those who progressed to severe AS, patients were subdivided into Slow (n = 294, over 3.91 [IQR 3.11 to 5.10] years) versus Fast (n = 295, over 1.29 [IQR 0.85 to 1.85] years) Progressors, according to the median time between the 2 echocardiograms. The correlates of fast AS progression and its impact on cumulative survival and freedom from valve intervention were evaluated. On multivariate analysis, age, thickened left ventricle posterior wall, severe renal impairment, and aortic valve area were significantly associated with fast AS progression. Over a median follow-up of 6.34 (IQR 4.05 to 9.55) years, 228 patients (38.7%) died. Despite similar aortic valve intervention rates, Fast Progressors had worse 5-year survival (61.2% vs 81.9%, log-rank p <0.001) and event-free (valve intervention and all-cause mortality) survival rates (16.2% vs 55.9%, log-rank p <0.001). On multivariable Cox analysis, shorter progression to severe AS (in years) was independently associated with increased risk of all-cause mortality (hazard ratio 1.26, 95% confidence interval 1.16 to 1.37, p <0.001), or combined aortic valve intervention and death (hazard ratio 1.46, 95% confidence interval 1.38 to 1.55, p <0.001). In conclusion, fast progression from moderate to severe AS is associated with worse outcomes.

Prevalence and Prognostic Implications of Discordant Grading and Flow-Gradient Patterns in Moderate Aortic Stenosis.

BACKGROUND: The prognostic implications of discordant grading in severe aortic stenosis (AS) are well known. However, the prevalence of different flow-gradient patterns and their prognostic implications in moderate AS are unknown. OBJECTIVES: The purpose of this study was to investigate the occurrence and prognostic implications of different flow-gradient patterns in patients with moderate AS. METHODS: Patients with moderate AS (aortic valve area >1.0 and ≤1.5 cm2) were identified and divided in 4 groups based on transvalvular mean gradient (MG), stroke volume index (SVi), and left ventricular ejection fraction (LVEF): concordant moderate AS (MG ≥20 mm Hg) and discordant moderate AS including 3 subgroups: normal-flow, low-gradient moderate AS (MG <20 mm Hg, SVi ≥35 mL/m2, and LVEF ≥50%); "paradoxical" low-flow, low-gradient moderate AS (MG <20 mm Hg, SVi <35 mL/m2, and LVEF ≥50%) and "classical" low-flow, low-gradient moderate AS (MG <20 mm Hg and LVEF <50%). The primary endpoint was all-cause mortality. RESULTS: Of 1,974 patients (age 73 ± 10 years, 51% men) with moderate AS, 788 (40%) had discordant grading, and these patients showed significantly higher mortality rates than patients with concordant moderate AS (P < 0.001). On multivariable analysis, "paradoxical" low-flow, low-gradient (HR: 1.458; 95% CI: 1.072-1.983; P = 0.014) and "classical" low-flow, low-gradient (HR: 1.710; 95% CI: 1.270-2.303; P < 0.001) patterns but not the normal-flow, low-gradient moderate AS pattern were independently associated with all-cause mortality. CONCLUSIONS: Discordant grading is frequently (40%) observed in patients with moderate AS. Low-flow, low-gradient patterns account for an important proportion of the discordant cases and are associated with increased mortality. These findings underline the need for better phenotyping patients with discordant moderate AS.

Left ventricular remodelling patterns in patients with moderate aortic stenosis.

AIMS: Moderate aortic stenosis (AS) is associated with an increased risk of adverse events. Because outcomes in patients with AS are ultimately driven by the condition of the left ventricle (LV) and not by the valve, assessment of LV remodelling seems important for risk stratification. This study evaluated the association between different LV remodelling patterns and outcomes in patients with moderate AS. METHODS AND RESULTS: Patients with moderate AS (aortic valve area 1.0-1.5 cm2) were identified and stratified into four groups according to the LV remodelling pattern: normal geometry (NG), concentric remodelling (CR), concentric hypertrophy (CH), or eccentric hypertrophy (EH). Clinical outcomes were defined as all-cause mortality and a composite endpoint of all-cause mortality and aortic valve replacement (AVR). Of 1931 patients with moderate AS (age 73 ± 10 years, 52% men), 344 (18%) had NG, 469 (24%) CR, 698 (36%) CH, and 420 (22%) EH. Patients with CH and EH showed higher 3-year mortality rates (28% and 32%, respectively) when compared with patients with NG (19%) (P < 0.001). After multivariable adjustment, CH remained independently associated with mortality (HR 1.258, 95% CI 1.016-1.558; P = 0.035), whereas both CH (HR 1.291, 95% CI 1.088-1.532; P = 0.003) and EH (HR 1.217, 95% CI 1.008-1.470; P = 0.042) were associated with the composite endpoint of death or AVR. CONCLUSION: In patients with moderate AS, those who develop CH already have an increased risk of all-cause mortality. Assessment of the LV remodelling patterns may identify patients at higher risk of adverse events, warranting closer surveillance, and possibly earlier intervention.

Moderate aortic stenosis: importance of symptoms and left ventricular ejection fraction.

AIMS: The aim of this study is to investigate the independent determinants of survival in patients with moderate aortic stenosis (AS), stratified by severity of symptoms and left ventricular ejection fraction (LVEF). METHODS AND RESULTS: Patients with a first diagnosis of moderate AS (aortic valve area >1.0 and ≤1.5 cm2) were identified. Patients were stratified by New York Heart Association (NYHA) functional class (NYHA I, NYHA II, or NYHA III-IV) and LVEF (LVEF ≥60%, LVEF 50-59%, or LVEF <50%) at the time of moderate AS diagnosis. The primary endpoint was all-cause mortality, while the secondary endpoint included all-cause mortality and aortic valve replacement. Of 1961 patients with moderate AS (mean age 73 ± 10 years, 51% men), 1108 (57%) patients were in NYHA class I, while 527 (27%) and 326 (17%) patients had symptoms of NYHA class II and III-IV, respectively. Regarding LVEF, 1032 (53%) had LVEF ≥60%, 544 (28%) LVEF 50-59%, and 385 (20%) LVEF <50%. During a median follow-up of 50 (23-82) months, 868 (44%) patients died. On multivariable analysis, NYHA class II [hazard ratio (HR): 1.633; 95% confidence interval (CI): 1.431-1.864; P < 0.001], NYHA class III-IV (HR: 2.084; 95% CI: 1.797-2.417; P < 0.001), LVEF 50-59% (HR: 1.194; 95% CI: 1.013-1.406; P = 0.034), and LVEF <50% (HR: 1.694; 95% CI: 1.417-2.026; P < 0.001) were independently associated with increased mortality. CONCLUSION: Moderate AS is associated with poor long-term survival. Baseline symptom severity and LVEF are associated with worse outcomes in these patients. Patients with low-normal LVEF (<60%) and mild symptoms (NYHA II) already have an increased risk of adverse events.

Sex-Related Differences in Medically Treated Moderate Aortic Stenosis.

Background: Recent data showed poor long-term survival in patients with moderate AS. Although sex differences in left ventricular (LV) remodeling and outcome are well described in severe AS, it has not been evaluated in moderate AS. Methods: In this retrospective, multicenter study, patients with a first diagnosis of moderate AS diagnosed between 2001 and 2019 were identified. Clinical and echocardiographic parameters were recorded at baseline and compared between men and women. Patients were followed up for the primary endpoint of all-cause mortality with censoring at the time of aortic valve replacement. Results: A total of 1895 patients with moderate AS (age 73 ± 10 years, 52% male) were included. Women showed more concentric hypertrophy and had more pronounced LV diastolic dysfunction than men. During a median follow-up of 34 (13-60) months, 682 (36%) deaths occurred. Men showed significantly higher mortality rates at 3- and 5-year follow-up (30% and 48%, respectively) than women (26% and 39%, respectively) (p = 0.011). On multivariable analysis, male sex remained independently associated with mortality (hazard ratio 1.209; 95% CI: 1.024-1.428; p = 0.025). LV remodeling (according to LV mass index) was associated with worse outcomes (hazard ratio 1.003; CI: 1.001-1.005; p = 0.006), but no association was observed between the interaction of LV mass index and sex with outcomes. Conclusions: LV remodeling patterns are different between men and women having moderate AS. Male sex is associated with worse outcomes in patients with medically treated moderate AS. Further studies investigating the management of moderate AS in a sex-specific manner are needed.

Prognostic Implications of Associated Cardiac Abnormalities Detected on Echocardiography in Patients With Moderate Aortic Stenosis.

OBJECTIVES: This study aimed to evaluate the prevalence and prognostic value of the extent of extra-aortic valvular cardiac abnormalities in a large multicenter registry of patients with moderate AS. BACKGROUND: The prognostic significance of a new classification system that incorporates the extent of cardiac injury (beyond the aortic valve) has been proposed in patients with severe aortic stenosis (AS). Whether this can be applied to patients with moderate AS is unclear. METHODS: Based on the echocardiographic findings at the time of diagnosis of moderate AS (aortic valve area between 1.0 and 1.5 cm2 and dimensionless velocity index ratio of ≥0.25), a total of 1,245 patients were included and analyzed retrospectively. They were recategorized into 5 groups according to the extent of extra-aortic valvular cardiac abnormalities: none (Group 0), involving the left ventricle (Group 1), the left atrial or mitral valve (Group 2), the pulmonary artery vasculature or tricuspid valve (Group 3), or the right ventricle (Group 4). Patients were followed for all-cause mortality and combined endpoint (all-cause mortality, stroke, heart failure, or myocardial infarction). RESULTS: The distribution of patients according to the proposed classification was 13.1%, 26.8%, 42.6%, 10.6%, and 6.9% in Groups 0, 1, 2, 3, and 4, respectively. During a median follow-up of 4.3 (2.4 to 6.9) years, 564 (45.3%) patients died. There was a significant higher mortality rates with increasing extent of extra-aortic valvular cardiac abnormalities (log-rank p < 0.001). On multivariable analysis, the presence of extra-aortic valvular cardiac abnormalities remained independently associated with all-cause mortality and combined outcome, adjusted for aortic valve replacement as a time-dependent covariable. In particular, Group 2 and above were independently associated with all-cause mortality. CONCLUSIONS: In patients with moderate AS, the presence of extra-aortic valvular cardiac abnormalities is associated with poor outcome.

IL-11 is a crucial determinant of cardiovascular fibrosis.

Fibrosis is a common pathology in cardiovascular disease. In the heart, fibrosis causes mechanical and electrical dysfunction and in the kidney, it predicts the onset of renal failure. Transforming growth factor ß1 (TGFß1) is the principal pro-fibrotic factor, but its inhibition is associated with side effects due to its pleiotropic roles. We hypothesized that downstream effectors of TGFß1 in fibroblasts could be attractive therapeutic targets and lack upstream toxicity. Here we show, using integrated imaging-genomics analyses of primary human fibroblasts, that upregulation of interleukin-11 (IL-11) is the dominant transcriptional response to TGFß1 exposure and required for its pro-fibrotic effect. IL-11 and its receptor (IL11RA) are expressed specifically in fibroblasts, in which they drive non-canonical, ERK-dependent autocrine signalling that is required for fibrogenic protein synthesis. In mice, fibroblast-specific Il11 transgene expression or Il-11 injection causes heart and kidney fibrosis and organ failure, whereas genetic deletion of Il11ra1 protects against disease. Therefore, inhibition of IL-11 prevents fibroblast activation across organs and species in response to a range of important pro-fibrotic stimuli. These results reveal a central role of IL-11 in fibrosis and we propose that inhibition of IL-11 is a potential therapeutic strategy to treat fibrotic diseases.