Current issues in transcatheter aortic valve replacement

Abstract

Background: aortic stenosisAortic stenosis (AS) is one of the most common forms of valvular disease in Western countries (1-3). It shows a consistent association with age, with prevalence ranging from 0.2% in the 50-59-year group to 9.8% in the 80-89-year cohort (4). Its prevalence is expected to increase due to higher life expectancy and population aging (5,6). It is also the most common reason for heart valve replacement (7).In a recent editorial paper (8), Eugene Braunwald put in perspective the medical advances in severe AS therapy over the last 50 years since the publication of his seminal study on AS natural history (9). Patients with severe AS had a good survival during a long latency period with "increasing obstruction and myocardial overload" until being about 60 years old. Then severe symptoms appeared and survival was poor, with most patients having heart failure, syncope and/or angina, and dying in a few years. With surgery being then the only available etiological treatment, the aim was to identify the patients approaching to such turning point to recommend surgery even with its associated risk with early prostheses.Even though this typical course has been confirmed over the years (10-12), the survival curve has shown a clear-cut shift to the right with progressive symptoms appearing now in patients in their 7th to 9th decade (6). Medical advances have now led most AS patients to what Braunwald calls a "promised land" with a long survival and good quality

TAVR: A Review of Current Practices and Considerations in Low-Risk Patients

“…[ 21 , 22 ]. Complications of new PPM implantation were similar in recent low-risk TAVR trials to the those in the previous studies in higher-risk patients [ 54 ]. The Evolut Low-Risk TAVR Trial with self-expanding valves also showed that significantly more low-risk TAVR patients underwent postoperative permanent pacemaker (PPM) implantation than SAVR patients (17.4% vs. 6.1%, respectively) [ 18 ].…”

“…Balloon-expandable THV are associated with a lower risk of PPM implantation than self-expanding valves [ 37 , 53 , 55 , 56 ]. This is felt to be due to the increased radial force on the LVOT by self-expanding valves [ 54 ]. For example, an average of 25.8% of TAVR cases with the self-expanding CoreValve is associated with new PPM, while the average rates in TAVR with balloon-expanding SAPIEN valve are much lower at 6.5% [ 53 ].…”

“…The type of THV also plays a role, as seen with the higher rates of PPM with newer generation SAPIEN 3 THV, compared with the previous generation SAPIEN XT [ 56 , 57 ]. The higher complication rate in SAPIEN 3 valves are attributed to the increased length, implantation height, and radial force exerted by its fabric skirt [ 54 , 57 ]. Preoperative TAVR evaluation should include assessment for patient risk factors such as baseline conduction disturbances and LVOT calcification to assist procedural planning and to minimize the risk of PPM implantation [ 55 ].…”

“…Understanding the patient and procedural factors that predict postoperative PPM insertion are important when counseling low-risk patients about the possible need for PPM [ 55 ]. Conduction abnormalities that occur as a complication of TAVR are transient in a considerable number of patients [ 54 ]. Cohort studies that included a variety of TAVR prostheses have shown that long-term pacemaker dependency ranged from 27% to 68% of patients with PPM [ 54 ].…”

Potential Role and Prognostic Value of Erythropoietin Levels in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement

“…Aortic stenosis remains the most common heart valve disease with a poor prognosis if not treated. Trans-catheter aortic valve replacement (TAVR) has dramatically improved prognosis in selected patients with severe aortic stenosis, particularly in those not eligible for surgical replacement ( 9 ). Certain prognostic biomarkers (including those reflecting anemia, renal dysfunction, and malnutrition) ( 10 – 13 ) have been shown to be associated to lower survival rates.…”