Concept: Aortic valve stenosis
Echocardiography and tomographic imaging have documented dynamic changes in aortic stenosis (AS) geometry and severity during both the cardiac cycle and stress-induced increases in cardiac output. However, corresponding pressure gradient vs. flow relationships have not been described.
Background Previous trials have shown that among high-risk patients with aortic stenosis, survival rates are similar with transcatheter aortic-valve replacement (TAVR) and surgical aortic-valve replacement. We evaluated the two procedures in a randomized trial involving intermediate-risk patients. Methods We randomly assigned 2032 intermediate-risk patients with severe aortic stenosis, at 57 centers, to undergo either TAVR or surgical replacement. The primary end point was death from any cause or disabling stroke at 2 years. The primary hypothesis was that TAVR would not be inferior to surgical replacement. Before randomization, patients were entered into one of two cohorts on the basis of clinical and imaging findings; 76.3% of the patients were included in the transfemoral-access cohort and 23.7% in the transthoracic-access cohort. Results The rate of death from any cause or disabling stroke was similar in the TAVR group and the surgery group (P=0.001 for noninferiority). At 2 years, the Kaplan-Meier event rates were 19.3% in the TAVR group and 21.1% in the surgery group (hazard ratio in the TAVR group, 0.89; 95% confidence interval [CI], 0.73 to 1.09; P=0.25). In the transfemoral-access cohort, TAVR resulted in a lower rate of death or disabling stroke than surgery (hazard ratio, 0.79; 95% CI, 0.62 to 1.00; P=0.05), whereas in the transthoracic-access cohort, outcomes were similar in the two groups. TAVR resulted in larger aortic-valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascular complications and less paravalvular aortic regurgitation. Conclusions In intermediate-risk patients, TAVR was similar to surgical aortic-valve replacement with respect to the primary end point of death or disabling stroke. (Funded by Edwards Lifesciences; PARTNER 2 ClinicalTrials.gov number, NCT01314313 .).
Background We compared transcatheter aortic-valve replacement (TAVR), using a self-expanding transcatheter aortic-valve bioprosthesis, with surgical aortic-valve replacement in patients with severe aortic stenosis and an increased risk of death during surgery. Methods We recruited patients with severe aortic stenosis who were at increased surgical risk as determined by the heart team at each study center. Risk assessment included the Society of Thoracic Surgeons Predictor Risk of Mortality estimate and consideration of other key risk factors. Eligible patients were randomly assigned in a 1:1 ratio to TAVR with the self-expanding transcatheter valve (TAVR group) or to surgical aortic-valve replacement (surgical group). The primary end point was the rate of death from any cause at 1 year, evaluated with the use of both noninferiority and superiority testing. Results A total of 795 patients underwent randomization at 45 centers in the United States. In the as-treated analysis, the rate of death from any cause at 1 year was significantly lower in the TAVR group than in the surgical group (14.2% vs. 19.1%), with an absolute reduction in risk of 4.9 percentage points (upper boundary of the 95% confidence interval, -0.4; P<0.001 for noninferiority; P = 0.04 for superiority). The results were similar in the intention-to-treat analysis. In a hierarchical testing procedure, TAVR was noninferior with respect to echocardiographic indexes of valve stenosis, functional status, and quality of life. Exploratory analyses suggested a reduction in the rate of major adverse cardiovascular and cerebrovascular events and no increase in the risk of stroke. Conclusions In patients with severe aortic stenosis who are at increased surgical risk, TAVR with a self-expanding transcatheter aortic-valve bioprosthesis was associated with a significantly higher rate of survival at 1 year than surgical aortic-valve replacement. (Funded by Medtronic; U.S. CoreValve High Risk Study ClinicalTrials.gov number, NCT01240902 .).
Calcific aortic valve stenosis (CAVS) is common in the ageing population and set to become an increasing economic and health burden. Once present, it inevitably progresses and has a poor prognosis in symptomatic patients. No medical therapies are proven to be effective in holding or reducing disease progression. Therefore, aortic valve replacement remains the only available treatment option. Improved knowledge of the mechanisms underlying disease progression has provided us with insights that CAVS is not a passive disease. Rather, CAVS is regulated by numerous mechanisms with a key role for calcification. Aortic valve calcification (AVC) is actively regulated involving cellular and humoral factors that may offer targets for diagnosis and intervention. The discovery that the vitamin K-dependent proteins are involved in the inhibition of AVC has boosted our mechanistic understanding of this process and has opened up novel avenues in disease exploration. This review discusses processes involved in CAVS progression, with an emphasis on recent insights into calcification, methods for imaging calcification activity, and potential therapeutic options.
- JAMA : the journal of the American Medical Association
- Published almost 5 years ago
IMPORTANCE Aortic stenosis is the most common form of valvular heart disease. Progression of aortic stenosis is very slow and highly variable. Decisions about when to perform valve surgery are made by subjective assessment of patient symptoms and objective measures of the valve and ventricular function by transthoracic echocardiography. OBJECTIVE To review current concepts regarding the development, progression, and assessment of aortic stenosis; the appropriate monitoring intervals for transthoracic echocardiography; and the indications for valve procedures. EVIDENCE REVIEW Guidelines and literature search. FINDINGS Angina, exertional syncope, and heart failure are key symptoms indicating a need for intervention. The frequency of valvular monitoring by transthoracic echocardiography is guided by the disease severity. Despite evidence of severe disease, valve procedures can safely be deferred if patients experience no symptoms and have normal left ventricular ejection fraction. Asymptomatic patients with severe aortic stenosis may subconsciously curtail their activities to avoid symptoms. Apparently, asymptomatic patients can undergo a carefully monitored exercise stress test to confirm both their asymptomatic status and hemodynamic response to exercise. Bioprosthetic valves are a good replacement alternative for older patients who are good surgical candidates and who have no need for warfarin therapy. For patients who are at high or very high risk of cardiac surgery, transcutaneous aortic valve implantation is an increasing available and preferred over medical management. CONCLUSIONS AND RELEVANCE Asymptomatic patients with severe aortic stenosis require frequent monitoring of their subjective symptoms combined with objective measurement of aortic valve gradient and ventricular function by transthoracic echocardiography. Although conventional surgical replacement remains the mainstay of therapy for aortic stenosis, transcutaneous aortic valve implantation options are evolving.
There are no studies comparing trans-catheter aortic valve implantation to conservative management in patients with chronic kidney disease stage 3-5 and severe aortic stenosis. We saught to compare mortality rate and change in renal function in this patient population.
Sex differences in risk factors of aortic valve calcification (AVC) by echocardiography have not been reported from a large prospective study in aortic stenosis (AS).
Based on the early results of the Placement of Aortic Transcatheter Valves (PARTNER) trial, transcatheter aortic valve replacement (TAVR) is an accepted treatment for patients with severe aortic stenosis who are not suitable for surgery. However, little information is available about the late clinical outcomes in such patients.
Calcific aortic valve stenosis (CAVS) is a common and life-threatening heart disease and the current treatment options cannot stop or delay its progression. A GWAS on 1009 cases and 1017 ethnically matched controls was combined with a large-scale eQTL mapping study of human aortic valve tissues (n = 233) to identify susceptibility genes for CAVS. Replication was performed in the UK Biobank, including 1391 cases and 352,195 controls. A transcriptome-wide association study (TWAS) reveals PALMD (palmdelphin) as significantly associated with CAVS. The CAVS risk alleles and increasing disease severity are both associated with decreased mRNA expression levels of PALMD in valve tissues. The top variant identified shows a similar effect and strong association with CAVS (P = 1.53 × 10-10) in UK Biobank. The identification of PALMD as a susceptibility gene for CAVS provides insights into the genetic nature of this disease, opens avenues to investigate its etiology and to develop much-needed therapeutic options.
Calcific aortic stenosis (AS) is the most common form of valve disease in the western world and affects over 2.5 million individuals in North America. Despite the large burden of disease, there are no medical treatments to slow the development of AS, due at least in part to our incomplete understanding of its causes. The CHARGE extra-coronary calcium consortium reported a genome-wide association study (GWAS) demonstrating that genetic variants in LPA are strongly associated with aortic valve (AV) calcium and clinical AS. Using a Mendelian randomization study design, it was demonstrated that the effect of this genetic variant is mediated by plasma lipoprotein(a) (Lp[a]), directly implicating elevations in Lp(a) as a cause of AV calcium and progression to AS. This discovery has sparked intense interest in Lp(a) as a modifiable cause for aortic valve disease. Herein, we will review the mounting epidemiological and genetic findings in support of Lp(a) mediated valve disease, discuss potential mechanisms underlying this observation and outline the steps to translate this discovery to a much needed novel preventive and/or therapeutic strategy for aortic valve disease.