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