Current Treatment and Future Trends Anthony J. Palazzo, M.D.F.A.C.S.

Objectives Brief discussion of most common pathologic valvular disease involving aortic and mitral valves Focus on aortic stenosis and mitral regurgitation Indications for surgical intervention Best choice of prosthetic device Current and future trends

Aortic Stenosis Etiology Degenerative (Calcification ) Bicuspid Rheumatic

Aortic Stenosis - Classification IndicatorMildModerateSevere Jet Velocity (m/s)< >4.0 Mean Gradient (mm Hg) < >40 Aortic Valve Area (cm²) > <1.0 Normal Aortic Valve Area 2-4 cm²

Aortic Stenosis-Pathophysiology Increased transvalvular gradient Increased left ventricular afterload Leads to development of LVH

Aortic Stenosis-Natural History Multiple echocardiographic studies have demonstrated that the average rate of decrease in aortic valve area is approximately 0.12 cm² per year Ross and Braunwald study (1968)- landmark paper revealing natural history as it relates to symptoms average survival with angina/syncope 3 yrs average survival with dyspnea 2 yrs average survival with CHF 1.5 yrs

Aortic Stenosis-Natural History Loma Lima study Retrospective review of 453 patients with documented severe aortic stenosis on ECHO Treated non-surgically Survival at 1, 5, and 10 years was 62%, 32% and 18% Demonstrated grave prognosis of patients with severe aortic stenosis AnnThorSurg, 2006

Aortic Stenosis-Indications for Surgery Patients with symptoms Asymptomatic patients with evidence of diminished left ventricular function (EF < 50%) Asymptomatic patients with normal ventricular function should be followed closely with serial echocardiography every 6 months due to known history of progression of cm² and risk of death of 1-3% per year

Aortic Stenosis-Salient Points Once diagnosis is suspected echocardiogram is single best non-invasive diagnostic test to determine aortic valve morphology, gradient and jet velocity Symptomatic patients should be referred for surgical evaluation Asymptomatic patients need to be followed closely for natural progression of disease Asymptomatic patients with diminished left ventricular function should be referred for surgery

Aortic Regurgitation-Etiology Calcific degeneration (mixed lesion with stenosis) Bicuspid aortic valve Connective tissue disease (Marfan’s) Aortic aneursym Aortic dissection Endocarditis

Aortic Regurgitation- Pathophysiology Increased left ventricular overload Left ventricular dilatation Diminishing left ventricular function

Aortic Regurgitation-Indications for Surgery Symptomatic patients with severe aortic regurgitation patients with angina have >10% mortality/year >20% mortality/year with CHF Endocarditis with hemodynamic decompensation Asymptomatic patients surgery for patients with EF <50% surgery for patients with evidence of left ventricular distension (end-diastolic dimension > 75 mm and end-systolic dimension > 55 m)

Mitral Stenosis Normal mitral valve area 4-6 cm² Rheumatic heart disease most common cause prevalence decreased significantly Thickening and calcification of leaflets Thickening of subvalvular structures (chords) May have mixed lesions-MS/MR Stenosis tends to progress slowly

Mitral Stenosis-Classification IndicatorMildModerateSevere Mean Gradient (mm Hg) <55-10>10 PA systolic pressure (mm Hg) < >50 Mitral Valve Area (cm²) > <1.0 Normal mitral valve area = 4-6 cm²

Mitral Stenosis-Indications for Surgery Patients with severe mitral stenosis with class NYHA class III and IV symptoms who are not candidates for percutaneous balloon mitral valvulotomy (patients with mixed lesions or heavy calcification) Asymptomatic patients with severe MS and severe pulmonary hypertension (PAP > 60 mm Hg) No therapy recommended in asymptomatic patients without evidence of severe pulmonary hypertension

Mitral Regurgitation-Etiology Degenerative “myxomatous” isolated leaflet prolapse Barlow’s disease Ischemic acute- ruptured papillary muscle/chord 2° AMI chronic- chronic myocardial ischemia Endocarditis

Mitral Regurgitation-Etiology Isolated “P-2” segmental prolapse

Mitral Regurgitation-Etiology Barlow’s disease

Ischemic Mitral Regurgitation Chronic ischemic mitral regurgitation annular dilatation papillary muscle retraction

Mitral Regurgitation-Diagnosis ECHO most informative non-invasive diagnostic test Assess leaflet morphology Chordal rupture Leaflet prolapse Regurgitant jets Ejection fraction

Mitral Regurgitation-Indications for Surgery (Class I indications) Symptomatic acute mitral regurgitation ruptured chord ruptured papillary muscle Symptomatic patients with chronic severe MR as long as EF > 30% Acute endocarditis with hemodynamic compromise, persistent sepsis, annular abscess, recurrent emboli Asymptomatic patients with severe MR and EF %

Mitral Regurgitation-Class IIa and IIb Indications Patients with severe MR with class III-IV symptoms and EF 55 mm and if a repair is highly likely There are 2 class IIb indications with asymptomatic patients with severe MR with EF > 60% who develop new onset atrial fibrillation and/or pulmonary hypertension (PAP > 50 mm Hg)

Mitral Regurgitation-Asymptomatic Asymptomatic patients with severe MR should be followed closely with ECHO every 6 months If there is evidence of left ventricular dysfunction with a decreased EF < 60 %, patients should be referred for surgery Preoperative EF important predictor of long term survival after mitral valve surgery

Effect of preoperative EF Long term postoperative prognosis is related to preoperative EF Pre-op EFNormal EFEF 50-60%EF < 50% 10 yr survival73 %53 %32 % Circulation, 1995

Mitral Regurgitation-Salient Points In asymptomatic patients with severe mitral regurgitation ventricular function should be followed closely If EF decreases to < 60% or left ventricular end systolic diameter dimension exceeds 40 mm patient should be referred for surgery Mitral valve repair is the ideal procedure

Prosthetic Valves No “perfect” prosthetic valve Bioprosthetic valves versus mechanical bioprosthetic Avoids long- term anticoagulation Limited durability mechanical Long-term anticoagulation Excellent durability

Prosthetic Valves porcinebovine pericardial mechanical

Prosthetic Valves-Selection Generally, if patient is > 65 a tissue valve is recommended Due improvements in the manufacturing process tissue valves have increased durability demineralization to prevent calcification “zero pressure” tissue fixation General trend to place tissue valves in younger patients Ultimate decision is patient’s

Prosthetic Valve Selection Some tissue valves have demonstrated 85% 15 year structural free deterioration Some evidence to suggest antiplatelet therapy may be sufficient anticoagulation in select patients with mechanical AVR (not a guideline) select cohort normal LV function normal sinus rhythym bileaflet mechanical valve ongoing clinical trails to determine efficiacy

Early Anticoagulation in bioprosthetic valves Historically “early” anticoagulation recommended in immediate postoperative period for tissue valves is warfarin for 3 months (AHA/ACC guidelines) Expanding clinical evidence to support use of antiplatelet therapy alone after aortic tissue valve placement in early postoperative period unless there is some other indication for warfarin¹΄² 1.JTCS, JTCS,2010

Percutaneous Therapy TAVI (transcatheter aortic valve implantation) Reserved for patients with severe aortic stenosis who are not surgical candidates for open procedure Recently FDA approved Likely will be regulated Should involve societal (STS) oversights and database Should be collaborative, multidisciplinary approach

Percutaneous Aortic Valve ? Long term durability Aortic insufficiency equivalent 1 year survival¹ compared to open surgery in some studies 1. NEJM, 2010