PICO QuestionIn patients over the age of 65 with symptomatic aortic stenosis, will standard aortic valve replacement or transcatheter aortic valve replacement have a lower mortality rate after 1 year?

What is Aortic Stenosis?Aortic stenosis is the narrowing of the aortic valve due to calcifications of its leaflets. It‘s incidence usually increases with age. If left untreated, aortic stenosis can cause symptoms such as syncope, chest pain and dyspnea, all which can greatly increase the rate of mortality.

Standard Aortic Valve Replacement vs Transcatheter Aortic Valve Replacement

Standard Aortic Valve ReplacementThe standard approach for an aortic valve replacement involves a surgical procedure to replace the patient’s diseased aortic valve with either a mechanical or bioprosthetic valve. This procedure is usually done through a sternotomy (open heart).

Patient CriteriaIt is recommended for almost all patients that are symptomatic from their aortic stenosis. There are a few patients that are not eligible for this procedure. The surgery cannot be done if there are more pressing medical conditions or if the patient will not likely survive surgery. If the patient is hemodynamically unstable and cannot go through the open heart surgery immediately, an aortic balloon valvotomy can be performed until the valve can ultimately be replaced.

Procedure-A 6-8 inch incision is made down the sternum.-The heart is connected to a bypass circuit and the heart put into a hypothermic state for protection.-The aorta is cut and the aortic valve is exposed.-The diseased valve is removed and a prosthetic valve is sewn in.-The aorta is closed, cardiac function resumed, the patient is weaned off the bypass circuit, and the sternum is sewn back together with wires.

Transcatheter Aortic Vlave ReplacementTAVR is a procedure used to treat symptomatic aortic stenosis. An artificial collapsed aortic valve is guided through a large vessel(usually the femoral artery) in a retrograde fashion to the aortic valve. The valve is meticulously placed into position and expanded to push aside and replace the stenotic aortic valve. The Sapien catheter heart valve was approved in November of 2011.

Patient CriteriaTAVR is used to treat symptomatic aortic stenosis in patients where the risk of surgery are unacceptably highAND. The decision is made by an experienced cardiothoracic surgeon, a multidisciplinary valve team and by risk stratification using the Society of Thoracic Surgens (STS) model. There are also certain criteria that must be met including:-Calcific aortic valve stenosis with the following present on echocardiogram:-Severly calcified vavle leaflets with reduced motion -An aortic valve area (AVA) of less than 1cm2 or indexed effected oriface of less than 0.5cm2/m2

Procedure-A collapsed artificial valve is introduced through a large vessel, most commonly the femoral artery, and it is progressed retrograde until it reaches the aortic valve.-Through guidance of a transesophageal echo and fluoroscopy, the collapsed valve is placed into the stenotic aortic valve and expanded to replace it.

Placement of AoRtic TraNscathetER ValvesComparison of TAVR/THV vs. Standard AVR

ConclusionThis study shows that TAVR is superior in all-cause mortality rates than standard AVR. Conventional standard AVR is being challenged by TAVR which is showing an advantage in areas such as recovery time, lower bleeding complications, new atrial fibrillation onset and availability to patients who can not undergo invasive surgery. Still, standard AVR shows a better outcome for incidences of stroke. As TAVR advances and becomes more refined, it certainly has the potential to replace the need for invasive open heart surgery in replacing stenotic aortic valves.

By: Victoria Adams and Paul Cho

References-Bonow, R. O., Mann, D. M., Zipes, D. P., & Libby, P. (2012). Management of valvular heart disease. InBraunwald's Heart Disease - A Textbook of Cardiovascular Medicine (9th ed., p. 1468). Philadelphia, PA: Elsevier Saunders. -Shabir, D. B. (2011, January 26). Medelineplus. Retrieved from http://www.nlm.nih.gov/medlineplus/ency/article/007408.htm-Smith, R. (2012, 01 25). Aortic valve replacement - recovery-Townsend Jr., C. M., Beauchamp, R. D., Evers, B. M., & Mattox, K. L. (2012). Sabiston textbook of surgery. (19 ed., p. 1671). Philadelphia, PA: Elsevier Saunders

Outcome At 30 Days Standard TranscatheterAll-Cause Mortality 6.50% 3.40%All Stroke or TIA 2.40% 5.50%Major Stroke 2.10% 3.80%Major Vascular Complications 3.20% 11.00%Major Bleeding 19.50% 9.30%New Atrial Fibrillation 16.00% 8.60%New Pacemaker 3.60% 3.80%

Outcome At 1 Year Standard TranscatheterAll-Cause Mortality 26.80% 24.20%All Stroke or TIA 4.30% 8.30%Major Stroke 2.40% 5.10%Major Vascular Complications 3.50% 11.30%Major Bleeding 25.70% 14.70%New Atrial Fibrillation 17.10% 12.10%New Pacemaker 5.00% 5.70%

References-Gaasch, W., Brecker, S., & Aldea, G. (2012). Transcatheter aortic valve replacement. -Nielsen, H., Klaaborg, K., Nissen, H., Terp, K., Mortensen, P., Kjeldsen, B., Jakobsen, C., & Andersen, H. (2012). A prospective, randomised trial of transapical transcatheter aortic valve implantation vs. surgical aortic valve replacement in operable elderly patients with aortic stenosis: The staccato trial.8(3), 383-389. -Singh, I., Shishehbor, M., Christofferson, R., Tuzcu, E., & Kapadia, S. (2008). Percutaneous treatment of aortic valve stenosis. Cleveland Clinic Lournal of Medicine, 17(11), 805-812.

Otto, C., Lung, B., Butchart, E., Charlson, E., Smith, C., & Leon, M. (2011). The partner trial. Retrieved from http://ht.edwards.com/scin/edwards/eu/sitecollectionimages/products/transcathetervalves/partnerresultsab.pdf