Acquired Heart Disease

1. Acquired Heart Disease

2. NY Heart Association Classification • Class I: Patients with cardiac disease but without resulting limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea, or angina pain. • Class II: Patients with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or angina pain. • Class III: Patients with cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary physical activity causes fatigue, palpitation, dyspnea, or anginal pain. • Class IV: Patients with cardiac disease resulting in an inability to carry on any physical activity without discomfort. Symptoms of cardiac insufficiency or of the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased.

3. Preop Risk Assessment • Major predictors: • unstable coronary syndrome (recent MI) • decompensated heart failure (NYHA class IV), • significant arrhythmias and severe valvular disease. • Intermediate predictors: • mild angina (old MI) • compensated heart failure (NYHA class II and III), • Diabetes • renal insufficiency. • Mild predictors: • advanced age • uncontrolled systemic hypertension, • irregular rhythm • prior stroke • abnormal EKG

4. Specific surgical risk factors or procedures expose the patient to greater or lesser risk of a cardiovascular event. • High-risk procedures : • emergent, major procedures in the elderly • major vascular procedures • long general surgical procedures with anticipated large fluid shifts and/or blood loss (e.g., pancreatectomy, hepatic resection, or abdominoperineal resection). • Intermediate-risk procedures: • any intraperitoneal or intrathoracic operation • carotid endarterectomy • Orthopedic • head and neck procedures • Low-risk procedures: • Endoscopic • breast • superficial operations.

5. Assign a class • High, Intermediate, Low risk • Do noninvasive testing based on risk • If positive, pursue coronary angiography if possible • Remember, CAD has same risk factors as PVD (major vascular surgery)

6. Studies • EKG • CXR • ECHO -- see flow pattern and valvular insufficiency • Dobutamine stress echocardiograph • PPV for cardiac event is 20-40% • A negative test is 93 to 100% predictive that no cardiac event will occur. • Radionuclide Studies – thallium scan – uptake dependent on myocardial perfusion • PET good for looking at viability of underperfused areas  determine if capable to responding to reperfusion

7. Cardiac Catheterization • Measures pressures and cardiac output • Shunts • Determines anatomy • Coronary Angiography – measures the degree of disease • Can determine area of a cardiac valve

8. CAD • 1946 IMA to myocardial tunnel  flow low and abandoned • 1950’s coronary endarterectomy attempted • 1960’s first CABG with SVG at Cleveland Clinic • Primarily ATH being multifactorial with segmental plaque • Sx: angina, MI, CHF, arrhythmias, sudden death • MI is the most common serious complication of CAD • Modern therapy: early reperfusion with either thrombolytic therapy or emergent angioplasty • lowered the mortality to <5 • CHF may develop after MI • If late scarring, bypass grafting may not be beneficial

9. CABG • CABG may be indicated in patients with chronic angina, unstable angina, or postinfarction angina, and in asymptomatic patients with severe proximal lesions or patients with atypical symptoms who have easily provoked ischemia during stress testing. • In general, patients with more severe angina (CCS class III or IV symptoms) are most likely to benefit from bypass • The Veterans Administration Cooperative Study. • demonstrated improved long-term survival in patients with left main disease treated with surgical • The European Coronary Surgery Study Group. • Surgery was found to be associated with improved survival in patients with triple-vessel disease and in patients with double-vessel disease with proximal left anterior descending and circumflex artery lesions. • Coronary Artery Surgery Study. • improved survival with surgery in patients with triple-vessel disease and depressed cardiac function. • Unstable Angina • Most patients require urgent revascularization with either percutaneous coronary intervention (PCI) or CABG. • Acute Myocardial Infarction • CABG generally does not have a primary role in the treatment of uncompoccurlicated acute MI • PCI or thrombolysis is the preferred method of emergent revascularization • The primary indication for surgery after acute transmural MI is in patients who develop mechanical complications • Usually occurs 4 to 5 days after MI, • Need intra-aortic balloon pump (IABP) placed and undergo emergent repair • High mortality rates

10. The left IMA has a 10-year patency rate of approximately 95% when used as an in situ graft to the LAD. • Right IMA may be used to provide a second arterial conduit as either an in situ or a free --patency rates are approximately 70 to 80% at 10 years.

11. Saphenous vein grafts • Targets on the lateral and posterior walls of the heart. • The 10-year patency of saphenous vein grafts is only approximately 65% • patency is limited by the development of progressive intimal hyperplasia and late vein graft atherosclerosis. • Radial Artery Graft • Allen test • Excellent results

12. CABG Results • Mortality 1-3% • Variables that have been identified as influencing operative risk according to STS risk modeling include: • female gender, age, race, body surface area, NYHA class IV status, low ejection fraction, hypertension, PVD, prior stroke, diabetes, renal failure, chronic obstructive pulmonary disease, immunosuppressive therapy, prior cardiac surgery, recent MI, urgent or emergent presentation, cardiogenic shock, left main coronary disease, and concomitant valvular disease. Perioperative complications include MI, bleeding, stroke, arrhythmias, tamponade, wound infection, aortic dissection, pneumonia, respiratory failure, renal failure, GI complications, and multiorgan failure. • Angina completely relieved or markedly decreased in >98% of patients,. • Exercise capacity with most patients demonstrating a markedly improved functional response to exercise secondary to improved blood flow. • Late survival is similarly excellent after CABG, with a 5-year survival of >90% and a 10-year survival of 75 to 90 • Again depends on risk factors present

13. CABG versus Stent • The Bypass Angioplasty Revascularization Investigation Trial. • There was no significant difference in 5-year survival • PCI group required more repeat interventions, with 54% within 5 years vs. only 8% for CABG. • In diabetic patients with triple-vessel disease, CABG offered a clear survival advantage at 5 years, 80.6 vs. 65.5% with PCI (P = .003). • Arterial Revascularization Therapies Study Group. • At 1 year, death, stroke, and MI rates were similar • PCI patients had more recurrent symptoms, 16.8 vs. 3.5% in CABG patients. • The 1-year event-free survival rate was 73.8% with PCI compared with 87.8% with CABG. • New York State Study Group. • Long-term patient survival was superior with CABG rather than stenting in patients with two or more diseased coronary arteries.17 • Summary • When comparing CABG to PCI for the treatment of patients with CAD, results demonstrate that with appropriate patient selection both procedures are safe and effective, with little difference in mortality. PCI is associated with less short-term morbidity, decreased cost, and shorter hospital stay, but requires more late reinterventions. CABG provides more complete relief of angina, requires fewer reinterventions, and is more durable. Additionally, CABG appears to offer a survival advantage in diabetic patients with multivessel disease.

14. Valvular Heart Disease • Surgical rate increased as CABG rate declines • Surgical therapy is now recommended at a much earlier stage of the disease process in an attempt to maintain normal cardiac function long after valve surgery. • Surgical Options • Replacement • Repair

15. Valves • Mechanical Valves • excellent flow characteristics • an acceptably low risk of late valve-related complications • extremely low risk of mechanical valve failure • Must anticoagulate • Tissue Valves • Porcine or bovine • Low thromboembolism rate • Homografts • Uncertain durablity • Difficulty with preservation • Autografts • Pulmonary Valve as Aortic Valve and homograft for PV (Ross procedure)

16. Mitral Disease • Mitral Valve Disease • Mitral Stenosis • almost always caused by rheumatic heart disease • Mitral stenosis usually has a prolonged course after the initial rheumatic infection, and symptoms may not appear for 10 to 20 years. • Pulmonary congestion • Can develop mural thrombi • ECHO diagnostic • Balloon valvuloplasty if uncomplicated stenosis • Commissurotomy has advantage of addressing nonpliable or calcified valves • Valve Repair • procedure of choice for most patients with MV insufficiency, • the primary advance in MV repair resulted from work by Carpentier in the 1970s. • 15-year freedom from valve repair failure is >90% in patients with degenerative mitral insufficiency. • lower risks of thromboembolic- and anticoagulant-related complications

17. Mitral Disease • Mitral Insufficiency • Degenerative disease is the most common cause of mitral insufficiency in the United States, • The basic physiologic abnormality in patients with mitral insufficiency is regurgitation of a portion of the LV stroke volume into the left atrium. • This results in decreased forward blood flow and an elevated left atrial pressure, producing pulmonary congestion and volume overload of the left ventricle. • findings of mitral insufficiency are an apical holosystolic murmur and a forceful apical impulse • Surgery for any NYHA II (SOB on exertion). • Options • Repair • Replacement • Annuloplasty device • Commissurotomy • .

18. Aortic Disease • Aortic Stenosis • Primary causes of aortic stenosis include acquired calcific disease, bicuspid aortic valve, and rheumatic disease. • Must be reduced to one third its normal cross-sectional area before significant hemodynamic changes occur. • Moderate aortic stenosis is defined as an aortic valve area between 1.0 and 1.5 cm2 • Severe stenosis is defined as a valve area <1.0 cm2 • Aortic stenosis results in increased myocardial work and progressive concentric LV hypertrophy with little ventricular dilatation. • The classic symptoms of aortic stenosis include exertionaldyspnea, decreased exercise capacity, heart failure, angina, and syncope. • Once the patient becomes symptomatic, prompt operation is indicated. • Operative Indications • Aortic valve replacement is indicated for virtually all symptomatic patients with aortic stenosis. • Surgery also may be recommended for asymptomatic patients with aortic stenosis who have a progressive increase in the transvalvular gradient on serial echocardiographic studies, a rapid rise in diastolic dimensions, a valve area <0.80 cm2, progressive pulmonary hypertension, or right ventricular dysfunction during exercise testing. • Aortic Insufficiency • Multiple causes: degenerative, inflammatory, infectious etiology, etc • Produces volume loading strain on the LV • Repair for any NYHA II or above  may be irreversible once symptoms occur

19. IHSS • Idiopathic Hypertrophic SubaorticStenosis • Varying degrees of subaortic LV outflow tract obstruction • Dynamic component usually be provoked with volume depletion, vasodilators, or inotropes. • Operative Techniques • Surgical septalmyotomy and myectomy (Morrow technique)

20. Heart Failure • Transplant the gold standard for end-stage heart disease • CABG for ischemic cardiomyopathy • Myocardial viability is the pivotal

21. Assist Devices • Balloon Pump • balloon is inflated during diastole and deflated during systole. • Coronary blood flow is increased by improved diastolic perfusion, and afterload is reduced. • Generally, the IABP is used for a few days with minimal morbidity. • Ventricular Assist Devices • anytime the heart can no longer support the oxygen delivery demands of the body • Bridge to recovery or transplant • May be “destination” for non transplant candidates

22. Atrial Fibrillation • Cox Maze procedures • Series of surgical incisions and reconstruction of the atria such that the sinus mechanism is preserved • 98% success rate, an extremely low follow-up neurologic event rate • Interventional EP Lab • Ablation

23. Pacemakers • Pacemakers were first developed in the 1950s, patients attached with power cord • Now done with transvenous leads that require only a subcutaneous access procedure and fluoroscopic control. • Defibrillators • 1990s: ICDs created • Detect and treat ventricular tachyarrhythmias. • Battery charges a capacitor and delivers jolt of energy to myocardiuma

24. Myxoma • Myxomas • Sixty to 75% of cardiac myxomas develop in the left atrium • There is no tendency to invade other areas of the heart, and distant metastases are rarely reported • May be completely asymptomatic until it grows large enough to obstruct the MV or TV or fragments to produce embolispecimen. The neck of the mass that was obstructing the mitral orifice is clearly delineated. • Clinical Manifestations • Symptoms may include those of MV obstruction; peripheral embolization; or generalized autoimmune symptoms. • Treatment • Surgery should be performed as soon as possible after the diagnosis has been established due to the inherent risk of a disabling or fatal cerebral embolus

25. Endocarditis • AV MC site of prosthetic valve complications • MV MC site of native valve • TV MC site of IV drug users • S. aureus for 50%

26. Anticoagulation? • ABX Prophylaxis? • Best conduit for CABG? • CABG versus Stent? • A-fib management?