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Background: A comprehensive non-invasive evaluation of bioprosthetic mitral valve (BMV) function can be challenging. We describe a novel method to assess BMV effective orifice area (EOA) based on phase contrast (PC) cardiovascular magnetic resonance (CMR) data. We compare the performance of this new method to Doppler and in vitro reference standards. Methods: Four sizes of normal BMVs (27, 29, 31, 33 mm) and 4 stenotic BMVs (27 mm and 29 mm, with mild or severe leaflet obstruction) were evaluated using a CMR- compatible flow loop. BMVs were evaluated with PC-CMR and Doppler methods under flow conditions of; 70 mL, 90 mL and 110 mL/beat (n = 24). PC-EOA was calculated as PC-CMR flow volume divided by the PC- time velocity integral (TVI). Results: PC-CMR measurements of the diastolic peak velocity and TVI correlated strongly with Doppler values (r = 0.99, P < 0.001 and r = 0.99, P < 0.001, respectively). Across all conditions tested, the Doppler and PC-CMR measurement of EOA (1.4 ± 0.5 vs 1.5 ± 0.7 cm2, respectively) correlated highly (r = 0.99, P < 0.001), with a minimum bias of 0.13 cm2, and narrow limits of agreement (− 0.2 to 0.5 cm2). Conclusion: We describe a novel method to assess BMV function based on PC measures of transvalvular flow volume and velocity integration. PC-CMR methods can be used to accurately measure EOA for both normal and stenotic BMV's and may provide an important new parameter of BMV function when Doppler methods are unobtainable or unreliable. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to evaluate cardiac magnetic resonance (CMR) phase-contrast (PC) measures of a bioprosthetic aortic valve velocity time integral (PC-VTI) to derive the effective orifice area (PC-EOA) and to compare these findings with the clinical standard of Doppler echocardiography. Background Bioprosthetic aortic valve function can be assessed with CMR planimetry of the anatomic orifice area and PC measurement of peak transvalvular systolic velocity. However, bioprosthetic valves can create image artifact and data dropout, which makes planimetry measures a challenge for even experienced CMR readers. Methods From our institutional database, we identified 38 patients who had undergone 47 paired imaging studies (CMR and Doppler) within 46 days (median 3 days). Transvalvular forward flow volume by CMR was determined by 3 methods: ascending aorta flow, transvalvular flow, and left ventricular stroke volume. PC-EOA was derived as flow divided by PC-VTI, calculated with a semiautomated MATLAB (Mathworks, Natick, Massachusetts) application for integration of the instantaneous peak transvalvular velocity. Doppler EOA was assessed by the continuity method. Results PC-EOA by all 3 flow approaches demonstrated a strong correlation with Doppler EOA (r = 0.949, 0.947, and 0.874, respectively; all p < 0.001) and revealed good agreement (bias = 0.03, 0.03, and 0.28 cm 2 , respectively). With Doppler-derived EOA as the reference standard, CMR was able to correctly characterize 24 of 26 valves as normal (EOA >1.2 cm 2 ), 12 of 14 possibly stenotic valves (0.8 < EOA < 1.2 cm 2 ), and 5 of 7 stenotic valves (EOA <0.8 cm 2 ; k = 0.826). Conclusions We describe a new CMR-based method to derive the EOA for bioprosthetic aortic valves. This method compares favorably to traditional Doppler methods and might be an important additional parameter in the evaluation of prosthetic valves by CMR, particularly when Doppler methods are suboptimal or considered discordant with the clinical presentation. [ABSTRACT FROM AUTHOR]

Concerns about the efficacy and safety of intensive low-density lipoprotein cholesterol lowering in older patients have led to weaker recommendations in the U.S. guidelines for patients ≥75 years of age compared to younger patients. Data are sparse on long-term benefits of proprotein convertase subtilisin/kexin type 9 inhibition in older patients. This study aims to assess the long-term benefit of evolocumab among patients aged ≥75 years. The FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk) trial randomized 27,564 patients who were 18 to 85 years of age with atherosclerotic cardiovascular disease to evolocumab vs placebo with 2.2 years of median follow-up. In the open-label extension (FOURIER-OLE), 6,635 participants were transitioned to open-label evolocumab for an additional 5-year median follow-up. The primary endpoint (cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, or coronary revascularization) was compared based on the original allocation to evolocumab vs placebo stratified by age (<75 vs ≥75 years). Analyses were underpowered for individual components of the composite endpoint. The annualized incidence rates for adverse events of interest were calculated for the OLE population across age groups during the parent FOURIER trial by randomized treatment arm and during the combined parent and FOURIER-OLE studies for patients originally allocated to evolocumab. Of 27,564 patients, 2,526 (9%) were ≥75 years of age at entry into FOURIER (median age: 77 years [Q1-Q3: 76-79 years]). The median follow-up in FOURIER and FOURIER-OLE was 7.1 years (Q1-Q3: 6.7-7.6 years), with a maximum of 8.7 years. Earlier initiation of evolocumab reduced the rate of the primary endpoint at least as well in older (HR: 0.79; 95% CI: 0.64-0.97) as in younger patients (HR: 0.86; 95% CI: 0.80-0.92; P interaction = 0.43). The absolute risk reductions were 5.4% (95% CI: –2.0% to 12.8%) in older and 2.3% (95% CI: 0.1%-4.5%) in younger patients, leading to numbers needed to treat of 19 and 44, respectively. The annualized incidence rates of safety events generally appeared similar across treatment arms in both age groups. Early initiation of long-term evolocumab provides older patients with atherosclerotic cardiovascular disease cardiovascular benefits at least as good as those observed in younger patients, with a more favorable number needed to treat in older patients for reducing a composite endpoint and no significant safety concerns. These findings may be helpful in guiding future recommendations. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: In GALACTIC-HF (Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure) (n = 8,256), the cardiac myosin activator, omecamtiv mecarbil, significantly reduced the primary composite endpoint (PCE) of time-to-first heart failure event or cardiovascular death in patients with heart failure and reduced ejection fraction (EF) (≤35%).Objectives: The purpose of this study was to evaluate the influence of baseline EF on the therapeutic effect of omecamtiv mecarbil.Methods: Outcomes in patients treated with omecamtiv mecarbil were compared with placebo according to EF.Results: The risk of the PCE in the placebo group was nearly 1.8-fold greater in the lowest EF (≤22%) compared with the highest EF (≥33%) quartile. Amongst the pre-specified subgroups, EF was the strongest modifier of the treatment effect of omecamtiv mecarbil on the PCE (interaction as continuous variable, p = 0.004). Patients receiving omecamtiv mecarbil had a progressively greater relative and absolute treatment effect as baseline EF decreased, with a 17% relative risk reduction for the PCE in patients with baseline EF ≤22% (n = 2,246; hazard ratio: 0.83; 95% confidence interval: 0.73 to 0.95) compared with patients with EF ≥33% (n = 1,750; hazard ratio: 0.99; 95% confidence interval: 0.84 to 1.16; interaction as EF by quartiles, p = 0.013). The absolute reduction in the PCE increased with decreasing EF (EF ≤22%; absolute risk reduction, 7.4 events per 100 patient-years; number needed to treat for 3 years = 11.8), compared with no reduction in the highest EF quartile.Conclusions: In heart failure patients with reduced EF, omecamtiv mecarbil produced greater therapeutic benefit as baseline EF decreased. These findings are consistent with the drug's mechanism of selectively improving systolic function and presents an important opportunity to improve the outcomes in a group of patients at greatest risk. (Registrational Study With Omecamtiv Mecarbil/AMG 423 to Treat Chronic Heart Failure With Reduced Ejection Fraction [GALACTIC-HF]; NCT02929329). [ABSTRACT FROM AUTHOR]