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
O’Connor et al; Arch CV Dis,2009
No LV Reserve; Fixed AV LV Reserve; Pliable AV
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 • Valve resistance or stroke work loss • Dobutamine stress • CMR or CTA
TEE
3D
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 Sudden Death Unrecognized Symptoms
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.”
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.
Nazarian S. In press, JACC
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)
Incr
emen
tal P
rogn
ostic
Val
ue
Stress test
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