Valvular Heart Disease 2012: The Year of the Valve

2

Robert H. McQueen, MD, FACC Mountain States Medical Group – Cardiology January 27, 2012

4 • • •

Structural abnormalities and disorders of cardiac valve function result in valvular heart disease Disruption in the anatomic integrity of cardiac valves may result in disorders of the valve surface, valvular stenosis, valvular regurgitation, or mixed disease with stenosis and regurgitation.

Clinical understanding and experience of valvular heart disease has changed dramatically in the past 5 decades, due to a number of factors:

– – – –

Recognition of nonrheumatic causes Reduction in incidence of rheumatic fever Increased life expectancy Development of new technology for Dx and Tx

5 • • •

Although there has been a dramatic reduction in rheumatic valve disease in industrialized countries over the past 50 years, there has not been a similar reduction in valve surgery.

Calcific aortic stenosis and mitral annular calcification are common valvular abnormalities in the elderly, and their incidence has increased due to an increase in life expectancy.

Valvular heart disease still constitutes a major health problem even in industrialized countries, and will continue to do so with aging populations.

6

Valvular Disease

• •

Although the incidence of degenerative disease increases with age, aging itself does not appear to be the only factor.

The initial lesion of calcified aortic valve disease seems to involve an active process similar to that of atherosclerosis, including lipid deposition, macrophage infiltration, and production of other proteins which negatively affect the valvular structure

9

Aortic Stenosis

• • • • • •

Over 300,000 patients have severe AS worldwide Most commonly caused by age-related progressive calcification (> 50% of cases) usually occurs later, 70-80 yr of age. Some degree of calcification found in 75% of people > 85.

Congenital Bicuspid AS (30-40%) usually occurs earlier, 40 –50 yr of age. 1-1.5% of population have bicuspid aortic valves Acute rheumatic fever (<10%) HTN, DM, Elevated Lipoproteins, and Uremia may encourage/accelerate process Severe AS found in 2% over age 65, 3% over 75, and 4% over 85

10

Severe AS Patients Not Undergoing AVR Have a Shorter Life Expectancy Than Those Receiving AVR

1 0.8

0.6

0.4

0.2

0 1yr Survival of patients with severe AS with and without AVR 1yr 87% 2yr 78% P < 0.0001

5yr 68% AVR n = 80 No AVR n = 197 52% 2yr 40% 5yr 22% 0 2 4 6 Time in Years 8 10 12 Number at risk 80 197 63 97 54 67 41 48 33 37 26 29 16 17 8 9 4 6 3 4 2 1 AVR group No AVR group

1. Varadarajan P, Kapoor N, Bansal RC, Pai RG. Survival in elderly patients with severe aortic stenosis is dramatically improved by aortic valve replacement: results from a cohort of 277 patients aged ≥ 80 years.

Euro J Cardiothorac Surg

. 2006;30:722-727.

11

Aortic Stenosis Symptoms

• • • • • • • •

Degree dependent Mild/Mod – Few if any symptoms Severe – Syncope, CHF, and Angina Most often AS presents with SOB/DOE As gradient increases, concentric hypertrophy develops as a result of excessive pressure loading Later progresses to LV dilation/thinning with ultimate function deterioration and increased filling pressures CHF and AS = 2 year mortality of 50% Syncope (usually exertional) = 3 yr mortality of 50%

12

Aortic Stenosis

• •

Angina occurs as LVH progresses and inability to supply thickened myocardium with adequate oxygenation.

Angina = 50% 5 yr mortality

13

Aortic Stenosis - Diagnosis

• • • • •

Adequate H & P EKG = LVH with possible strain/ischemia if advanced CXR = Calcification of Aortic valve with possible Cardiac enlargement secondary to LVH Echo (TTE or TEE) best non-invasive imaging modality, 3D may provide additional information Cardiac Cath (R/L/LV/Root) remains gold standard for exact gradient measurement and coronary angiogram

14 •

Aortic Stenosis – Medical Treatment

In general, all medical therapies have poor effect on AS, important to treat associated symptoms

– –

Angina = B-Blocker or Ca blocker Avoid peripheral vasodilators, unable to increase C.O. to compensate

–

(NTG, ACE/ARB, Alpha blockers, Hydralazine) If no significant symptoms: Mild/Mod stenosis = Echo every 1-2 yr, +/- GXT Mod/Severe = Echo every 3-6 months, ? Stress Valve replacement if symptoms, Echo changes

15

Aortic Stenosis – Invasive options

• •

Balloon Valvuloplasty generally ineffective long-term and used only for palliative treatment or as bridge to subsequent procedure Surgical valve replacement remains the Gold Standard for alleviation of symptoms and improved survival

16

Aortic Regurgitation

• • • •

Half of all cases due to aortic root dilation which is usually idiopathic (> 80%) but may be secondary to aging, syphilitic aortitis, osteogenesis imperfecta, or dissection 15% of cases secondary to bicuspid AV 15% of cases secondary to rheumatic fever May accompany AS with post-stenotic dilation of AO root and subsequent associated regurgitation

17

Aortic Regurgitation

• •

Acute: Sudden increase in LV volume, less efficient contraction (shifting Frank-Starling curve), increased end-diastolic pressures resulting in pulmonary edema Severe = life-threatening emergency associated with high mortality if AVR not performed

• •

Chronic: LV hypertrophy and volume overload is compensated for over time Eventual LV decompensation and filling pressures escalate = SOB/CHF (PND, DOE)

18

Aortic Regurgitation – Diagnostic Tools

• • • • • •

Adequate H & P EKG may suggest LVH if chronic CXR may show AV calcification with possible cardiac enlargement +/- widened mediastinum Echo (TTE/TEE) remains best non-invasive tool Cardiac Cath with Root, Gold Standard CT may be helpful to R/O Dissection

19

Aortic Regurgitation - Treatment

• •

Vasodilators preferred (ACE/ARB, Hydralazine) but only if HTN present, for afterload reduction AVR indicated if:

– – –

Any symptoms suggestive of CHF Fall in EF < 50% regardless of sxs Severe LV dilation or abnormal GXT If stable without above findings: Mild/Mod AI: Echo every 1-2 yr +/- GXT Mod/Severe AI: Echo every 3-6 mos

20

Mitral Stenosis

• • • •

Almost all cases are secondary to rheumatic fever Normally latent period @ 16 yrs. Once symptoms develop, progression to stenosis @ 9 years.

Little role of medical therapy other than symptomatic support Patients with severe MS who refuse MV replacement/repair, 44% survival @ 5 yr, 32% @ 10yr.

21

Mitral Stenosis

• • •

LA/LV gradient increases with increased HR or Cardiac output As LA/LV gradient increases, the amount of time to fill the LV increases, now relying on the “atrial kick” Ultimately diastolic filling is insufficient resulting in decreased C.O. and elevated LA pressures = pulmonary edema

22

Mitral Stenosis - Diagnosis

• • • • •

Adequate H & P EKG = P mitralie (Broad notched P), possible AF CXR = LAE, pulm edema Echo = Best non-invasive test (TEE > TTE) Cath (R/L with simultaneous LV/Wedge) – Gold Standard

23

Mitral Stensis – Treatment Options

• •

If no symptoms, Echocardiographic monitoring If Symptoms:

– –

Mitral valve replacement/repair Mitral Valvuloplasty:

• • • •

Leaflet mobility Leaflet thickening Subvalvular thickening Amount of calcification present Class III or IV only If score > 8, surgery preferred

24

Mitral Valvuloplasty

• • •

Performed via femoral vein Requires trans-septal puncture Three stagged balloon

– – –

1 st : Inflated in LV and pulled back against MV leaflets 2 nd : Inflated in LA to secure leaflets in center 3 rd : Center inflated to “crack” leaflets Usually all performed in < 30 sec Most serious complication is severe MR (torn leaflet or subvalvular apparatus) requiring surgical repair Requires vigilant F/U for restenosis: 70-75% free of restenosis @ 10 yr 40% free of restenosis @ 15 yr

25

26

Mitral Regurgitation

• • • • • •

Most common form of valvular heart disease Problem with either papillary muscle or chordae tendineae can produce sub-valvular MR Most common cause is papillary muscle fibrosis (ischemic papillary muscle damage) after MI with either shortening or lengthening and possible LV dilation 50% of all infarcts have some involvement of the papillary muscles Myxomatous degeneration most common form of valvular regurgitation All result in failure in coaptation

27

Mitral Regurgitation - Diagnosis

• • • •

Adequate H & P EKG = LAE, LVH, ? AF Echo (TEE/TTE) best diagnostic tool Cardiac cath best invasive

28

Mitral Regurgitation – Treatment Options

• •

Medical treatment consist of After-load reduction (ACE/Hydralazine) Acute management may require IABP, IV Nipride and surgical repair of Valve

•

Mitral Replacement or Repair +/- ring

•

Replace when symptoms present, LV dysfunction (EF<50), or LVESD > 45

29

New Percutaneous Valvular Therapies

30

Aortic Stenosis - Percutaneous Therapies

• •

Surgical Aortic valve replacement is not performed in up to 1/3 of eligible pts due to advanced age, co morbidities, previous cardiac surgery, low EF, Concomitant CAD and patient refusal Percutaneous treatment of CAD is now the treatment of choice for most individuals, however, the treatment of structural heart disease via a percutaneous approach has been slower to evolve

31 • • • •

Transcatheter Aortic Valve Implantation (TAVI) allows a less invasive means of valve replacement via a transfemoral, transapical, or subclavian approach with favorable results in terms of procedural success, hemodynamic performance, peri procedural complications, and survival Currently in US, only Pulmonic valves are approved (Melody – Medtronic) Outside US, 2 current platforms in use, Edwards Sapian Valve and Medtronic Corevalve. Over 15,000 percutaneous valves implanted worldwide since 2002

32 • • •

Edwards Sapian Valve

3 bovine pericardial leaflets hand-sewn to a stainless steel balloon expandable stent with fabric covering of the lower portion of the stent to facilitate formation of a seal Valve leaflets undergo anticalcification treatment during production in an attempt to maximize longevity Currently produce in 3 sizes: 23,26, and 29 mm

33

Transcatheter Valves Three Primary Components:

1.

2.

3.

Tissue Valve Supporting Frame Delivery System

34

35

Medtronic CoreValve Revalving System

• • •

Self-expanding nitinol stent (no balloon delivery) Delivered through a 18Fr system 2 Current sizes: 26 & 29mm

CoreValve Experience

36

More than 10,000 implants in 34 countries

Design & System Components Design

•

Transfemoral approach for beating-heart, transcatheter aortic valve implantation (TAVI) Components:

•

18Fr catheter delivery system

Over-the-wire 0.035 compatible •

Self-expanding multi-level Nitinol frame

37 •

Porcine pericardial tissue valve

Caution: The CoreValve® System is not currently available in the USA for clinical trials or for sale. CoreValve is a registered trademark of Medtronic CV Luxembourg S.a.r.l. 37

Valve Design Features

Delivery Fixation Hoops • • • Nitinol Frame

Self-expanding frame Radiopaque design Memory shaping properties

Orientation Crowns • • Pericardial Porcine Tissue Valve

Supra-annular valve function Tall commissures

• • • Multi-Level Radial Forces

Outflow Aspect Hoop Strength Inflow Aspect

38 • • Sealing Skirt

Porcine pericardium Intra-annular sealing

Caution: The CoreValve® System is not currently available in the USA for clinical trials or for sale. CoreValve is a registered trademark of Medtronic CV Luxembourg S.a.r.l. 38

39

40

Position and Fixation

Inflow 41 Outflow Caution: The CoreValve® System is not currently available in the USA for clinical trials or for sale. CoreValve is a registered trademark of Medtronic CV Luxembourg S.a.r.l. 41

42

TAVI Inclusion

• • •

Severe symptomatic AS with Aortic valve area less than 1 cm2 or mean gradient > 40mmHg, advanced age > 80 If age < 80 then one of the following: Liver cirrhosis, Significant pulmonary HTN, previous cardiac surgery, porcelain aorta, severe COPD, recent PE Aortic annulus sized by TEE or CT to avoid size mismatch

43

TAVI Exclusion

• • •

Bulky aortic calcification ? Bicuspid aortic valve Short Distance (< 8mm) between the aortic annulus and the Left main coronary

44

TAVI Results

• • • • •

20% reduction in mortality with significant improvement in Valve gradients, quality of life, reduced hospitalizations compared with Med Rx Most common hospital complications were bleeding (31%), CIN (18%), Vascular (16%), CVA (11%), Coronary occlusion, Persistent AV block Most common long-term complication is Peri valvular leak, @ 75% mild and well tolerated, @ 20% mod/severe and require either post-dilation, placement of second valve, or surgery Causes: Prosthesis mismatch, valve malposition, under expansion of stent, valve damage, operator experience MSCT to evaluate annulus to Coronary distance

45 • • •

TAVI Results

1 year mortality after TAVI = 10% (Pt age, disease states) MACE @ 30% Stroke after Surgical AVR

– –

1.5% but increases to 2-4% in high-risk pts 1.5 – 6% at 1yr At 1 year, TAVI and SAVR showed similar rates of survival, although there were important differences in periprocedural risks ? Long-term valve durability Newer Generation Devices – fewer complications

46

TAVI Placement

High deployment:

– –

Device embolization Coronary ischemia owing to compromise of one or both coronary ostia

–

Aortic injury Low Deployment: - Impingement upon the AV node causing bradycardia or BBB or MV apparatus resulting in acute and ofter poorly tolerated MR

47

TAVI Summary

• • • • •

Team approach mandatory Extensive pre-procedure planning/imaging Family discussions Intra-Cardiac Echo/TEE needed Emergency back-up procedures in place

•

No substitute for experience

48

49

? Mitral Valve Replacement

• • • •

Percutaneous replacement of MV not currently possible due to anatomic features of the MV that make fixation and peri-valvular seal desires a challenge Calcified aortic valve OK for TAVI, other locations require prosthetic material to provide support for Transcatheter stent-mounted valves Annuloplasty ring in Annulus may provide “landing zone” for secure deployment Valve-in-Valve has been done successfully in animal models

50

Mitral Regurgitation MitraClip – Abbott Vascular

• • • • •

Edge-to-edge technique (Alfieri 1991, Double Orifice), Open heart procedure that sutured free edge of leaflets at site of MR which created 2 orifices Safe, effective, and durable Historically Open procedure - Min. invasive robotic with direct (trans-atrial) off-pump suture based approach – Percutaneous Clip 2003 first in Man Clip currently available in Europe and in trials in US (Everest II) in high-risk pts with functional MR

51

MitraClip – Abbott Vascular

• • •

24Fr, trans-septal approach Cobalt/chromium clip Capture of MV leaflets at site of MR

52

Everest II Results

•

At 12 months, the rates of primary end point for efficacy were 55% MitraClip vs 73% Surgical

• • • • •

Death: 6% each group Surgery for valve dysfunctin: 20% vs 2% Severe MR: 21% vs 20% Major adverse events: 15% vs 48% at 30 days At 12 months, both had improved LV size, functional class, and QOL measures Although percutaneous repair was less effective at reducing MR, the procedure was associated with superior safety and similar improvements in outcomes

53