New Imaging for Aortic Valve Disease Anthony DeMaria Judy and Jack White Chair Director, Sulpizio CV Center University of California, San Diego
Imaging in Aortic Stenosis Valve morphology calcification Valve gradient and area Concomitant regurgitation Ventricular function Ascending aorta
Aortic Stenosis and 3D Echo Goland et al, Heart, 2007
Aortic Stenosis and 3D Echo Goland et al, Heart, 2007
Aortic Stenosis and 3D Echo Goland et al, Heart, 2007
Aortic Stenosis and 3D Stroke Volume Poh et al; EHJ, 2008
Aortic Stenosis and 3D Stroke Volume Poh et al; EHJ, 2008
Aortic Stenosis and 3D Stroke Volume Poh et al; EHJ, 2008
Ao Fibroelastoma
Stress Echo in AS No LV Reserve; Fixed AV LV Reserve; Pliable AV O Connor et al; Arch CV Dis,2009
Low Gradient (Severe) Aortic Stenosis LGAS Marked reduction of stroke volume Severe LV dysfunction with low EF Normal EF with small LV and high impedance Small LV EDV, marked concentric hypertrophy High valvuloaortic impedance (Zva) Women, older patients, hypertensives
AS with Low Gradient: Assessment Catheterization Image aortic leaflets TEE 3D Valve resistance or stroke work loss Dobutamine stress CMR or CTA
It s hard to improve on the safety pin
Flow Imaging by CMR
Aortic Stenosis and CMR John et al: JACC, 2003
CMR and Aortic Stenosis
Cardiac Magnetic Resonance Advantages Quality images Uniformly attainable Inherently 3D High reproducibility Fibrosis and scar Perfusion?Coronary anatomy Disadvantages Often unavailable Stationary Complex Expensive Patient isolated Claustraphobic No pacemaker/icd Valves less certain
CTA of Normal Aortic Valve
Aortic Stenosis: MDCT vs TEE Feuchtner et al; JACC, 2006
AS: MDCT vs Echo vs Cath Lembcke et al: Invest Radiol, 2009
AS: MDCT vs Echo vs Cath Lembcke et al: Invest Radiol, 2009
Valve Stenosis by MDCT Tops et al: JACC: CV Img, 2008
Value of Imaging in AS Morph Ca++ Grad AVA Regurg LV Fnct Asc Ao Echo ++++ ++ ++++ ++++ +++ +++ CMR ++++ ++ ++ ++++ +++ ++++ MDCT ++++ ++++ ++ + ++ ++++
Aortic Stenosis Most common valve disease of industrialized world 3% over 75 yrs have severe AS With aging, prevalence will double in the next 20 years
No prospective, randomized, control trials comparing conservative medical to surgical therapy of asymptomatic aortic stenosis have been performed
Criteria for AS Severity Aortic Peak Velocity 4.0-5.0 m/sec Aortic Mean Gradient 40 mm/hg
Medical Therapy of AS No therapy of proven benefit exists Control coronary risk factors BP, smoking, lipids, etc Statins: SEAS trial negative Disease level may have been too advanced ACEI: not contraindicated Physical exertion related to AS severity No restriction for mild asymptomatic AS
Clinical Status of AS Asymptomatic Unrecognized Symptoms Sudden Death
Sudden Death in AS: Prospective Studies AVE 1%/year Surgical mortality: 1-5%/year
Effect Rates and Risk in AS
Post-op Sudden Death in AS However, even after corrective surgery, patients exhibit elevated risk of sudden death (11). In fact, sudden death has been reported to be the most frequent mode of death after aortic valve surgery and appears to associate with greater left ventricular hypertrophy (12). Some of these sudden deaths are likely due to causes other than arrhythmia, such as embolism or valvular dehiscence. However, Blackstone and colleagues found normal prosthetic valve and peri-prosthetic myocardium in 8 of 15 autopsies after sudden death post valve replacement (13). It appears, therefore, that even after corrective surgery for aortic stenosis, some patients remain predisposed to sudden death. Nazarian S. In press, JACC 11.Bloomfield P, Wheatley DJ, Prescott RJ, Miller HC. Twelve-year comparison of a Bjork-Shiley mechanical heart valve with porcine bioprostheses. N Engl J Med 1991;324:573-9. 12.Foppl M, Hoffmann A, Amann FW, et al. Sudden cardiac death after aortic valve surgery: incidence and concomitant factors. Clin Cardiol 1989;12:202-7. 13.Blackstone EH, Kirklin JW. Death and other time-related events after valve replacement. Circulation 1985;72:753-67.
Risk Factors in AS aortic valve calcification rapid increase in pressure gradient higher aortic valve velocities inappropriate high left ventricular mass abnormal response or symptoms on exercise testing Elevated BNP Increased valvulo-arterial impedance Echo/Doppler parameters (eg stress)
AS Survival vs Velocity Rosenhek et al; Circ, 2010
(2000)
Stress test Incremental Prognostic Value
Course of Asymptomatic AS Pellikka et al; Circ, 2005
Risk Factors in Euroscore
Risk Levels in Euroscore
AS Guidelines of ESC
AS Guidelines of ACC/AHA
ESC Guidelines for AS
Limitations of Existing Reports Study results (eg echo) are often reported May influence the decision for surgery Symptoms or surgery are often endpoints Decision to operate is subjective Death in un-operated is often non-cardiac Medical patients have more co-morbidities Pts may refuse surgery upon symptoms
Asymptomatic AS: Final Thoughts In absence of symptoms, close medical follow up is generally indicated Surgery for established risk factors Reduced EF Heavy calcification Rapidly increasing velocity Abnormal exercise test AVR only if risk of surgery is low TAVI may change the landscape