Assessment of EuroSCORE in Patients Undergoing Aortic Valve Replacement

A Sneak-Peek into the Physician's Brain: A Retrospective Machine Learning-Driven Investigation of Decision-Making in TAVR versus SAVR for Young High-Risk Patients with Severe Symptomatic Aortic Stenosis

Transcatheter aortic valve replacement (TAVR) has rapidly become a viable alternative to the conventional isolated surgical aortic valve replacement (iSAVR) for treating severe symptomatic aortic stenosis. However, data on younger patients is scarce and a gap exists between data-based recommendations and the clinical use of TAVR. In our study, we utilized a machine learning (ML) driven approach to model the complex decision-making process of Heart Teams when treating young patients with severe symptomatic aortic stenosis with either TAVR or iSAVR and to identify the relevant considerations. Out of the considered factors, the variables most prominently featured in our ML model were congestive heart failure, established risk assessment scores, previous cardiac surgeries, a reduced left ventricular ejection fraction and peripheral vascular disease. Our study demonstrates a viable application of ML-based approaches for studying and understanding complex clinical decision-making processes.

Quantifying the Shift Toward Transcatheter Aortic Valve Replacement in Low-Risk Patients: A Meta-Analysis

BACKGROUND

In recent years, use of transcatheter aortic valve replacement has expanded to include patients at intermediate- and low-risk cohorts. We sought to determine disease prevalence and treatment distribution including transcatheter aortic valve replacement eligibility in low-risk patients across 37 advanced economies.

METHODS AND RESULTS

Four systematic searches were conducted across MEDLINE, EMBASE, and the Cochrane database for studies evaluating disease prevalence, severity, decision making, and survival in patients with aortic stenosis. Estimates of disease prevalence and treatment eligibility were calculated using stochastic simulation and population data for the 37 countries comprising the International Monetary Fund's advanced economies index. Fifty-six studies comprising 42 965 patients were included across 5 domains: prevalence, severity, symptom status, treatment modality, and outcome. The pooled prevalence in the general population aged 60 to 74 years and >75 years was 2.8% (95% confidence interval [CI], 1.4%-4.1%) and 13.1% (95% CI, 8.2%-17.9%), respectively-corresponding to an estimated 16.1 million (95% CI, 12.2-20.3) people in 37 advanced economies. Of these, an estimated 3.2 million (95% CI, 2.2-4.4) patients have severe aortic stenosis with 1.9 million (95% CI, 1.3-2.6) eligible for surgical aortic valve replacement. There are ≈485 230 (95% CI, 284 550-66 7350) high-risk/inoperable patients, 152 690 (95% CI, 73 410-263 000) intermediate-risk patients, and 378 890 (95% CI, 205 130-610 210) low-risk patients eligible for transcatheter aortic valve replacement.

CONCLUSIONS

With a prevalence of 4.5%, an estimated 16.1 million people aged ≥60 years across 37 advanced economies have aortic stenosis. Of these, there are ≈1.9 million patients eligible for surgical aortic valve replacement and 1.0 million patients eligible for transcatheter aortic valve replacement.

Non-invasive and invasive predictors of paravalvular regurgitation post CoreValve® stent prosthesis implantation in aortic valves

OBJECTIVES

The long-term success of CoreValve® stent prosthesis (Medtronic) implantation for severe aortic valve stenosis is limited by postprocedural paravalvular regurgitation (PVR).

METHODS

We have retrospectively investigated preinterventional cardiac 256-slice computed tomography (CT) scans and aortography to define predictors for mild, moderate, or severe PVR, in a blinded fashion.

RESULTS

We investigated 100 consecutive patients with a mean aortic valve area (AVA) of 0.69 cm(2) and a mean age of 79.4 years. PVR was defined by echocardiography as mild (63), moderate (18), or severe (19). We found no differences according to AVA, left ventricular function, deployed stent size, calcification rate of the aortic valve, and stent position. Anatomically, the annular size and the angle between the left ventricular outflow tract (LVOT) and the ascending aorta demonstrated significant (P < 0.05) differences in the severity of the PVR: an LVOT: ascending aorta angle >12.6°, annulus area >8.9 cm(2) , and annulus diameter difference >3.9 mm. The multivariate analysis demonstrated that deviation angle, difference of aortic annulus (longitudinal-orthogonal), and CoreValve size were independent predictors of PVR.

CONCLUSION

Our data demonstrate the feasibility of cardiac CT to evaluate predictors of PVR post-CoreValve placement. We support the aortic annulus (the area as well as the diameter differences) and the deviation of the linear slope from LVOT to ascending aorta as predictors of severe paravalvular regurgitations poststent implantation.

Using simple imaging markers to predict prognosis in patients with aortic valve stenosis and unacceptable high risk for operation

Aortic valve stenosis (AS) in patients >75 years of age is a challenge for diagnosis and management of every day clinical routine. Therefore, this clinical follow-up study aims to investigate predictors of death in patients with advanced stages of AS. In a single-center study, all patients (n = 157) with primary conservatively treated severe AS (mean age 78 ± 6 years) were included. All patients had initially refused aortic valve replacement (AVR). During a median follow-up of 2.6 years (quartiles 1.7, 3.8), 62 patients with severe AS switched to AVR and 95 remained conservatively treated (no AVR). Routine clinical data were assessed together with conventional echocardiography including the measurement of longitudinal wall function and deformation (mitral ring displacement and longitudinal strain and strain rate imaging). The end points were all-cause and cardiac death. During follow-up, cardiac death occurred in 49% in no-AVR group. In a Cox regression analysis, New York Heart Association functional class, valvuloarterial impedance, stroke volume, longitudinal strain and strain rate, and mitral annular displacement identified an increased risk of all-cause death (hazard ratio [HR] for mitral annular displacement 15.9, 95% confidence interval [CI] 6.24 to 40.86, p <0.001, positive predictive value 91%). In contrast, ejection fraction or EuroSCORE was not predictive (ejection fraction: HR 1.3, 95% CI 0.82 to 2.33, p = 0.25; EuroSCORE: HR 1.1, 95% CI 0.64 to 2.02, p = 0.64). Furthermore, in multivariate regression analysis, only longitudinal mitral annular displacement and longitudinal strain rate was a significant predictor of all-cause and cardiac death risk. These data show that prognosis in elderly patients with AS is determined by symptoms, hemodynamics, and particularly by cardiac long-axis function. Thus, for risk stratification, a comprehensive assessment of cardiac function including the measurement of longitudinal mitral annular displacement should be considered.

Non-invasive and invasive evaluation of aortic valve area in 100 patients with severe aortic valve stenosis: comparison of cardiac computed tomography with ECHO (transesophageal/transthoracic) and catheter examination

BACKGROUND

Current guidelines place emphasis on the determination of aortic valve area (AVA) for defining an appropriate treatment strategy. Invasive and non-invasive modalities are used to perform planimetric [transesophageal echocardiography (TEE) and cardiac multidetector computed tomography (MDCT)] and calculated [catheter examination (CE), transthoracic echocardiography (TTE)] AVA measurements.

PURPOSE AND METHODS

We investigated 100 patients admitted to evaluate the AVA using cardiac MDCT (CT), TEE/TTE as well as invasive CE.

RESULTS

In all 100 patients we calculated a mean AVA of 0.79±0.29cm(2) (female 50/100, 0.70±0.19cm(2), male 0.9±0.21cm(2)) determined by all investigated examinations (mean±SEM). AVA measurements determined by CT were significantly greater (0.86±0.25cm(2)) than those determined by CE: 0.75±0.18cm(2), p=0.01. Echocardiographically determined AVA was comparable to CE (statistically not significant). Similar results were seen in all patients regardless of gender, presence of atrial fibrillation, and heart rate. We calculated a mean AVA for each patient and evaluated the variance of the AVA determined through investigated specific examinations as the bias. Overall, we found for CT 0.13±0.1cm(2), CE 0.13±0.11cm(2), TEE 0.16±0.09cm(2), and for TTE 0.16±0.08cm(2) a specific statistical non-significant variance. On subgroups: sinus rhythm, atrial fibrillation, females, males or combination, we found no further significant relevance for the specific variance.

CONCLUSION

Our data suggest the feasibility of cardiac MDCT to evaluate the correct AVA regardless of rhythm, heart rate, and sex. The planimetric concept to determine the AVA with CT displaces the "gold-standard" CE with respect to elucidating the potencies for complications, i.e. cerebral stroke. Regardless of CT's accessing of AVA measurement the TTE examination should remain the primary method of screening for aortic valve pathologies.

A meta-analysis of transcatheter aortic valve implantation versus surgical aortic valve replacement

BACKGROUND

Our preliminary meta-analysis suggests that transcatheter aortic valve implantation (TAVI) may not reduce the 30-day mortality rate over surgical aortic valve replacement (AVR) in high-risk patients with severe aortic stenosis (AS). We performed an updated formal meta-analysis of TAVI vs AVR for reduction not only of early but also of late all-cause mortality in AS.

METHODS

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through October 2012. Eligible studies were randomized controlled trials or adjusted observational comparative studies of TAVI vs AVR enrolling individuals with AS and reporting early (30-day or in-hospital) or late all-cause mortality, or both, as an outcome. Odds ratios or hazard ratios with 95% confidence intervals (adjusted odds ratios or hazard ratios in case of observational studies) were abstracted from each study.

RESULTS

We identified two randomized trials and 15 adjusted observational studies enrolling 4,873 patients with severe AS. Pooled analysis suggested no significant difference in early (odds ratio, 0.92; 95% confidence interval, 0.70 to 1.19) and midterm (3-month to 3-year) total mortality (hazard ratio, 0.99; 95% confidence interval, 0.83 to 1.17) among patients assigned to TAVI vs AVR. Exclusion of any single study from the analysis did not substantively alter the overall result of our analysis. No evidence of significant publication bias was found.

CONCLUSIONS

Our meta-analysis of data of approximately 5,000 patients from 17 studies showed that TAVI is likely ineffective in reducing early and midterm all-cause mortality vs AVR in high-risk patients with AS.

The year in review: the surgical treatment of valvular disease-2011

This review highlights important advances in techniques, guidelines, outcomes and innovations in valve surgery during 2011.