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21.

Objectives

The purpose of this study was to describe patients with severe symptomatic aortic stenosis with normal flow and low gradients and determine whether they benefit from intervention.

Background

Severe symptomatic aortic stenosis is a progressive disease with high mortality. Although surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) are indicated for patients with high gradients (>40 mm Hg) or low gradients due to low flow, the approach for patients with normal flow and low gradients is poorly defined.

Methods

Consecutive adult patients who underwent echocardiography between 2012 and 2015 at Tel-Aviv Medical Center and had an aortic valve area of ≤1.0 cm2, a mean gradient of <40 mm Hg, a stroke volume index of >35 ml/m2, and symptoms formed the study group. Patients designated for intervention (SAVR or TAVR) had their procedure within 6 months of the echocardiogram; the others were treated conservatively. The endpoints were all-cause mortality and cardiac-related mortality.

Results

During the study period, 1,358 patients with an aortic valve area of ≤1.0 cm2 and symptoms were identified; 34% of these had normal flow and low gradient aortic stenosis and 303 were included. After mean follow-up of 652 days, 60 patients (20%) had died, with overall mortality rates of 28%, 10%, and 12% for conservatively treated, TAVR, and SAVR patients, respectively (p < 0.001). Using Cox regression with adjustment for other variables, TAVR was associated with improved survival versus conservative treatment (hazard ratio [HR]: 0.49; 95% confidence interval [CI]: 0.26 to 0.93; p = 0.03), and lower cardiac mortality (HR: 0.30; 95% CI: 0.10 to 0.74; p = 0.007) with no significant difference for SAVR versus TAVR. After propensity score matching of TAVR and conservatively treated patients, 25 of 94 (28%) conservatively treated and 10 of 94 (12%) TAVR patients had died (p = 0.016). In the matched cohort, Cox regression showed that TAVR had a significant association with improved survival (HR: 0.42; 95% CI: 0.20 to 0.86; p = 0.03).

Conclusions

Symptomatic patients with an aortic valve area of ≤1.0 cm2, normal flow, and low gradient may benefit from intervention as opposed to conservative treatment.  相似文献   
22.
23.

Objectives

The REAC-TAVI (Assessment of platelet REACtivity after Transcatheter Aortic Valve Implantation) trial enrolled patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) pre-treated with aspirin + clopidogrel, aimed to compare the efficacy of clopidogrel and ticagrelor in suppressing high platelet reactivity (HPR) after TAVI.

Background

Current recommendations support short-term use of aspirin + clopidogrel for patients with severe AS undergoing TAVR despite the lack of compelling evidence.

Methods

This was a prospective, randomized, multicenter investigation. Platelet reactivity was measured at 6 different time points with the VerifyNow assay (Accriva Diagnostics, San Diego, California). HPR was defined as (P2Y12 reaction units (PRU) ≥208. Patients with HPR before TAVR were randomized to either aspirin + ticagrelor or aspirin + clopidogrel for 3 months. Patients without HPR continued with aspirin + clopidogrel (registry cohort). The primary endpoint was non-HPR status (PRU <208) in ≥70% of patients treated with ticagrelor at 90 days post-TAVR.

Results

A total of 68 patients were included. Of these, 48 (71%) had HPR (PRU 273 ± 09) and were randomized to aspirin + ticagrelor (n = 24, PRU 277 ± 08) or continued with aspirin + clopidogrel (n = 24, PRU 269 ± 49). The remaining 20 patients (29%) without HPR (PRU 133 ± 12) were included in the registry. Overall, platelet reactivity across all the study time points after TAVR was lower in patients randomized to ticagrelor compared with those treated with clopidogrel, including those enrolled in the registry (p < 0.001). The primary endpoint was achieved in 100% of patients with ticagrelor compared with 21% with clopidogrel (p < 0.001). Interestingly, 33% of clopidogrel responder patients at baseline developed HPR status during the first month after TAVR.

Conclusions

HPR to clopidogrel is present in a considerable number of patients with AS undergoing TAVR. Ticagrelor achieves a better and faster effect, providing sustained suppression of HPR to these patients. (Platelet Reactivity After TAVI: A Multicenter Pilot Study [REAC-TAVI]; NCT02224066)  相似文献   
24.

Objectives

This study investigated the prognostic value of first-phase ejection fraction (EF1) in patients with aortic stenosis (AS), a condition in which left ventricular dysfunction as measured by conventional indices is an indication for valve replacement.

Background

EF1, the ejection fraction up to the time of maximal ventricular contraction may be more sensitive than existing markers in detecting early systolic dysfunction.

Methods

The predictive value of EF1 compared to that of conventional echocardiographic indices for outcomes was assessed in 218 asymptomatic patients with at least moderate AS, including 73 with moderate, 50 with severe, and 96 with “discordant” (aortic area <1.0 cm2 and gradient <40 mm Hg) AS, all with preserved EF, followed for at least 2 years. EF1 was measured retrospectively from archived echocardiographic images by wall tracking of the endocardium. The primary outcome was a combination of aortic valve intervention, hospitalization for heart failure, and death from any cause.

Results

EF1 was the most powerful predictor of events in the total population and all subgroups. A cutoff value of 25% (or EF1 of <25% compared to ≥25%) gave hazard ratios of 27.7 (95% confidence interval [CI]: 13.1 to 58.7; p < 0.001) unadjusted and 24.4 (95% CI: 11.3 to 52.7; p < 0.001) adjusted for other echocardiographic measurements including global longitudinal strain, for events at 2 years in all patients with asymptomatic AS. Corresponding hazard ratios for all-cause mortality in the total population were 17.5 (95% CI: 5.7 to 53.3) and 17.4 (95% CI: 5.5 to 55.2) unadjusted and adjusted, respectively.

Conclusions

EF1 may be potentially valuable in the clinical management of patients with AS and other conditions in which there is progression from early to late systolic dysfunction.  相似文献   
25.
Purpose: Transcatheter aortic valve replacement (TAVR) has emerged as a therapeutic option for severe aortic valvular stenosis (AS). To determine the indication for TAVR, it is mandatory to clarify the characteristics of the patients who were judged as inoperable for conventional aortic valve replacement (cAVR).Methods: Of 185 patients newly diagnosed as severe AS from March 2010 to April 2011, we studied the characteristics of 61 (33%) patients (mean age, 86 ± 8 years) who were judged as inoperable.Results: Younger patients (<85 years old, n = 22) had more major comorbidities and lower left ventricular ejection fraction than older patients (≥85 years old, n = 39). Mean estimated mortality for cAVR by Japan score was 7.0% ± 7.4%. Japan score did not correlate to age and was calculated relatively low in the older age group (6.2% ± 7.0%) than the younger age group (8.3% ± 8.1%).Conclusion: One thirds of severe AS patients were judged as inoperable. In advanced age patients, age itself and other factors, which are not included in the conventional scoring systems, might have contributed to the decision making not to perform cAVR by cardiologists. Further study is necessary to define risk factors except for age.  相似文献   
26.
27.
The assessment of myocardial function in the context of valvular heart disease remains highly challenging. The myocardium deforms simultaneously in 3 dimensions, and global left ventricular (LV) function parameters such as volume and ejection fraction may remain compensated despite the changes in myocardial deformation properties. Current guidelines recommend valve replacement/repair in the presence of symptoms or reduced LV ejection fraction, but the resolution of symptoms or recovery of LV function post-surgery may not be reliably predicted. A wealth of evidence currently suggests that LV dysfunction is frequently subclinical despite normal ejection fraction. It may precede the onset of symptoms and portend a poor outcome due to progressive myocardial remodeling and dysfunction during the post-operative period. The advent of novel tissue-tracking echocardiography techniques has unleashed new opportunities for the clinical identification of early abnormalities in LV function. This review gathers and summarizes current evidence regarding the use of these techniques to assess myocardial deformation in patients with valvular heart disease.  相似文献   
28.
29.
In recent years, experience with transcatheter aortic valve implantation has led to improved outcomes in elderly patients with severe aortic stenosis (AS) who may not have previously been considered for intervention. These patients are often frail with significant comorbid conditions.  相似文献   
30.
Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy. The prevalence of phenotypic expression, in the absence of another systemic or cardiac disease causing increased left ventricular (LV) wall thickness, is estimated to be 1:500. The frequency of clinical presentation is far less, highlighting the need for a non-invasive diagnostic imaging tool. Echocardiography is readily available and allows for structural characterization and hemodynamic assessment of the hypertrophic heart and to screen patients at-risk for HCM, such as first degree relatives of affected individuals, and differentiate HCM from the athletic heart. Echocardiography can also be used to assess for anatomic abnormalities of the mitral valve apparatus that may exacerbate LV outflow track obstruction and to further risk stratify patients during exercise. Finally, echocardiography plays an integral role in guiding alcohol septal ablation procedures.  相似文献   
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