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Surgery of Acquired Heart Defects. Definition of AHD. Abnormalities of heart morphology (especially valves) acquired during extraembryonic life due to pathologic processes and adversely affecting hemodynamics. Division of AHD. BACKGROUND Organic - Non-organic (relative) LOCALIZATION
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Definition of AHD Abnormalities of heart morphology (especially valves) acquired during extraembryonic life due to pathologic processes and adversely affecting hemodynamics.
Division of AHD • BACKGROUND Organic - Non-organic (relative) • LOCALIZATION Mitral – Aortic - Tricuspid –Pulmonary • HEMODYNAMICS Stenosis – Insufficiency- complex • COURSE Chronic - Acute
Etiology • Ischemic (mitral insufficiency) • Rheumatic (mitral stenosis) • Degenerative • mucoid degeneration (mitral insufficiency) • calcareous degeneration (aortic stenosis) • Infectious (valvular insufficiency)
Ischemic mitral insufficiencycurrently one of the most prevalent AHD • Acute – complication of AMI (rapture of pappilary muscle) -> cardiogenic shock / pulmonary edema (fatal in most of cases) • Chronic – restrictive type of mitral insufficiency caused by LV remodeling after myocardial infarction or due to chronic ischemia SCHOULD BE CORRECTED BY REPAIR (RIGID RING)
Rheumatic mitral stenosis – classic AHD with decreasing prevalence • Two times more prevalent in women • Self-aggression response to streptococcal antigens • Fibrosis and calcification of valvular endocardium • Nowadays relatively rare (antibiotics) • Correction: commissurotomy or MITRAL VALVE REPLACEMENT
Calcified aortic stenosis • The most prevalent AHD in the elderly, especially in men • Sometimes a problem is small diameter of aortic annulus (< 20 mm), especially in women • Correction: AORTIC VALVE REPLACEMENT (BIOPROSTHESIS)
Hemodynamics • COMPENSATORY MECHANISMS • Preload increase -> Excentric Hypertrophy of heart chambers • Afterload increase -> Concentric Hypertrophyof heart chambers • DECOMPENSATION • Decrease of cardiac output • Pulmonary and systemic congestion • Hypoxia • Congestive Heart Failure(CHF)
NEUROHORMONAL RESPONSE Sympathetic system (epinephrine) RAA mechanism (renin, aldosterone, angiotensin) AVP, cytokines (endothelin, interleukins) EFFECTS Retention of salt and water Heart remodeling (apoptosis) Catabolism Cachexy Multi-organ insufficiency Congestive Heart Failure
Complications of AHD • Arrhythmias (atrial fibrillation, ExV etc.) • Thrombo-embolic events (e.g. cerebral embolism with neurological dysfunctions) • Infectious endocarditis
Diagnostics • History and physical examination • ECG, chest X-ray • ECHOCARDIOGRAPHY • Invasive examination (heart catheterization) • Microbiological tests
HISTORY: - dyspnea (NYHA I-IV) angina (CCS I-IV) edema syncope palpitation fever history of stroke PHYSICAL EXAMINATION - heart murmur arrhythmia symptoms of heart failure neurological dysfunction Medical examination
ECG Heart axis abnormalities p mitrale/pulmonale Atrial fibrillation ST segment negative T wave CHEST X-RAY cardiomegaly Valvular calcifications features of pulmonary congestion hydrothorax Routine additional examinations
ECHOCARDIOGRAPHY • Diameters of heart chambers, heart walls thickness • Valvular morphology (calcifications, fibrosis) area of valvular ostia (cm2) • DOPPLER: valvular gradients (mmHg), degree ofregurgitation (I-IV), pulmonary pressure • LV systolic function: global (ejection fraction LVEF), regional • Intracardiac pathologies (thrombi, vegetations) • hydropericardium
Coronary Angiography indications in AHD before surgery • Angina or/and history of myocardial infarction • At least one risk factor of CAD e.g. age over 40 years • Ischemic etiology of a defect (mitral regurgitation) If significant lesions in coronary arteries are found the patient should undergo preoperative PCI or have CABG performed together with valvular procedure
Mitral Stenosis -symptoms • HISTORY: increasing dyspnea, palpitation, fatigue, cyanosis, often history of rheumatic feveror embolic events • PHYS: loud 1st heartsound, mitral diastolic murmur, arrhythmia, edema, hepatomegaly • ECG: Features of RV overload, p mitrale, often AF • X-RAY: hypertrophy of RV and LA, pulmonary congestion • ECHO: low mitral valve area, enlarged LA and RV, pulmonary hypertension >30 mmHg
Mitral insufficiency-symptoms • HISTORY: dyspnea, fatigue, often history of myocardial infarction • PHYS: mitral systolic murmur, arrhythmia • ECG: p mitrale, often AF, LV overload • X-RAY: left heart hypertrophy, pulmonary congestion • ECHO: enlarged LA and LV, mitral regurgitation
Aortic stenosis-symptoms • HISTORY: often asymptomatic, later dyspnea, angina and syncope, sudden death • PHYS: aortic systolic murmur • ECG: features of left ventricular overloadand hypertrophy • X-RAY: „aortic” heart silhouette • ECHO: concentric LV hypertrophy, high aortic systolic gradient
Aortic insufficiency - symptoms • HISTORY: dyspnea, angina • PHYS: aortic diastolic murmur, high and tense pulse • ECG: features of LV hypertrophy • X-RAY: „aortic” heart silhouette • ECHO: enlargement of LA and LV, aortic regurgitation
Indications for Surgery in AHDStrategy • Optimal timing (too early – increased risk of accumulation of long-term outcomes, too late – worse results due to irreversible cardiomyopathy (remodeling) and CHF • Method of correction (to repair or to replace? If replace, what prosthesis to use?) • Indications to other procedures (e.g. CABG, surgery of aorta etc.) may accelerate a decision about AHD correction so that it could be performed simultaneously
Aortic stenosis – indications to surgery • Symptomatic (dyspnea, angina, syncope) patients with severe aortic stenosis (gradient > 50 mmHg in ECHO) • Patients with moderate to severe aortic stenosis (gradient > 30 mmHg) referred to other cardiac surgery e.g. CABG • Asymptomatic patients with severe aortic stenosis and impaired LV function (EF<50%)
Aortic valve insufficiency – indications to surgery • Symptomatic patients (NYHA class II-IV) with severe aortic regurgitation (III-IV degree in ECHO) and LV diastolic diameter (LVdD) > 6,0 cm • Regardless to symptoms, patients with severe aortic regurgitation if: • LVEF 25-50% or LVdD > 7,5 cm • Referred to other cardiac surgery
Mitral stenosis – indications to surgery • Symptomatic patients (NYHA class II-IV) with moderate to severe mitral stenosis – mitral valve area (MVA) <1,5 cm2 • Regardless to symptoms, patients with severe stenosis (MVA < 1 cm2) and severe pulmonary hypertension (>60 mmHg)
Mitral insufficiency – indications to surgery • Symptomatic patients (NYHA class II-IV) with significant mitral regurgitation (III-IV degree in ECHO) and LV hypertrophy > 6 cm • Regardless to symptoms, patients with significant mitral regurgitation if: • EF<60% • Atrial fibrillation • Pulmonary hypertension > 50 mm Hg
Tricuspid insufficiency – indications to surgery (usuallyannuloplasty) Patients referred to other valvular procedures (usually mitral), with severe tricuspid regurgitation (III-IV degree in ECHO), pulmonary hypertension and enlarged right atrium
Patient’s preparation to scheduled operation of AHD • Optimal medical treatment (digitalis, diuretics, ACE inhibitors, beta-blockers) • Cure or remission of co-morbidities that can effect outcomes (e.g. peptic ulcer, inflammatory foci) • Red cells concentrate – 2 units (autotransfussion, family donation)
Almost every operation of AHD requires use of CARDIO-PULMONARY BY-PASS (CPB)
REPAIR (PLASTY) Should be always considered if possible in mitral and tricuspid insufficiency Method of choice in ischemic mitral insuff. The most physiological AHD correction No need for anticoagulation REPLACEMENTcalcified mitral and aortic stenosis infectious endocarditis If no chance for effective repair (excessive valve damage) in insufficiency Inexperienced surgeon No intraoperative TEE available To repair or to replace valve?
Tricuspid annuloplasty Modo Revuelta Modo De Vega
ADVANTAGES - more physiologicalflow- lower gradient (especially stentless)- no need for anticoagulation (unless AF) DISADVANTAGES- lower durability (calcification)- more difficult to implant (esp. stentless)- troublesome for storage (esp. homografts) Characteristics of biological valves
ADVANTAGES- high durability- easy to implant- widely available- easy to store DISADVANTAGES- necessity of lifelong anticoagulation- less physiological- higher gradients Characteristics of mechanical prostheses
MECHANICAL Previously implanted mechanical valve in other position Chronic renal failure ondialysis Necessity of anticoagulation for other reasons BIOLOGICAL Counter-indications for anticoagulation Age over 65 years Women in reproductive age Choice of prosthesis
Cumulative 15 years survival in patients after valve replacement with biological and mechanical prostheses >=70 <70