Anaesthesia For Valvular Heart Diseases Made by Dr

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Anaesthesia For Valvular Heart Diseases Made by: Dr. Meenal Aggarwal Moderator: Dr. Aparna

Anaesthesia For Valvular Heart Diseases Made by: Dr. Meenal Aggarwal Moderator: Dr. Aparna

Introduction

Introduction

 • Valvular ds: An increased burden on L or R ventricle • Could

• Valvular ds: An increased burden on L or R ventricle • Could be: ü Pressure overload (Stenotic lesions) ü Volume overload (Regurgitant lesions) • Initially tolerated d/t compensatory mechanisms Eventually cardiac muscle dysfunction CHF ; even sudden death

Preoperative Assessment • Aim: to know ü Severity of Disease ü Degree of impaired

Preoperative Assessment • Aim: to know ü Severity of Disease ü Degree of impaired myocardial contractility ü Presence of assoc. organ system diseases • O/H: Symptoms: ü Dyspnea, orthopnea, easy fatiguability (Impaired myocardial contractility) ü Anxiety, diaphoresis, resting tachycardia (Compensatory increase in sympathetic activity) ü Angina (d/t assoc CAD, or inc. myocardial O 2 demand)

 • Drug therapy: ü Beta Blockers ü Digitalis ü ACE inhibitors ü Vasodilators

• Drug therapy: ü Beta Blockers ü Digitalis ü ACE inhibitors ü Vasodilators Control HR (AS & MS: Allows diastolic filling) Control BP and so dec. afterload (AR, MR) ü Diuretics ü Ionotropes ü Antiarrhythmic drugs Control of CHF

 • O/E: Signs: ü Inspection: Raised JVP ü Auscultation: Basilar chest rales, S

• O/E: Signs: ü Inspection: Raised JVP ü Auscultation: Basilar chest rales, S 3, Murmurs: D/t turbulent flow across the defective valve o Note: character, location, intensity, direction of radiation o Systolic murmurs: AS, PS or MR, TR o Diastolic murmurs: MS, TS or AR, PR ü Dysrhythmias: AF (esp Mitral valve ds. ) i. e. with enlarged Lt atria

 • Lab Investigations: ü CXR: o Size & shape of heart & great

• Lab Investigations: ü CXR: o Size & shape of heart & great vessels o Pulmonary markings o Enlarged LA (Elevated Lt main bronchus, calcified valve) ü ECG: o Lt or Rt axis deviation (Lt or Rt ventricle hypertrophy) o P mitrale (Broad notched P wave in Mitral valve ds. ) o Dysrhythmias o Conduction abnormalities o Evidence or active ischemia or previous MI

ü Echo with doppler: o Evaluating significance of murmurs o Detection of antomical defects

ü Echo with doppler: o Evaluating significance of murmurs o Detection of antomical defects (Hypertrophy, chamber size, valve area) o Functional defects (Transvalvular pressure gradient, magnitude of valvular regurgitation) ü Cardiac Catheterisation: Solves discrepancies b/w clinical and echo findings o Presence & severity of stenosis or regurgitation o Intracardiac shunting o CAD

 • Transvalvular pressure gradient (TVPG) (Severe MS when > 10 mm. Hg, Severe

• Transvalvular pressure gradient (TVPG) (Severe MS when > 10 mm. Hg, Severe AS when > 50 mm Hg) • Pulmonary artery pressures (Pulmn HT) Assessment of Prosthetic Valve function: • Dysfunction (Change in intensity/ quality of clicks, new or change in characteristics of murmurs) ü Tranthoracic Echo: To assess ring stability and leaflet motion ü Transesophageal Echo: Better resolution ü MRI: For prosthetic valve regurg, paravalvular leak ü Cardiac Catheterisation: For TVPG, Effective valve area

 • Complications of prosthetic valves: üRisk of thromboembolism (Anticoagulation) üSubclinical intravascular hemolysis üRisk

• Complications of prosthetic valves: üRisk of thromboembolism (Anticoagulation) üSubclinical intravascular hemolysis üRisk of endocarditis (AB) • Management of anti coagulation: üCan be continued in minor surgery with min blood loss üFor major surgery (Stop warfarin 3 -5 days preop, UF heparin or LMWH started & continued upto day/ day before of surgery, restarted post op) üAvoid elective surgery with in 1 month after an acute thromboembolic episode

ü In pregnancy (TE prophylaxis to continue, S/C LMWH given + low dose aspirin)

ü In pregnancy (TE prophylaxis to continue, S/C LMWH given + low dose aspirin) • Prophylaxis of Bacterial endocarditis: ü Infection likely from frequent exposure to bacteremia ü Weigh Risk to benefit ratio (AB resistance) ü Prophylaxis given to following pts: 1. Prosthetic material for cardiac valve repair 2. Previous IE 3. CHD: Unrepaired CHD, Completely repaired with prosthetic material (during 1 st 6 months after procedure), Repaired defects with residual defect) 4. Cardiac transplant pt who develop valvulopathy

ü AB prophylaxis not required for GU or GIT procedure ü Required for skin

ü AB prophylaxis not required for GU or GIT procedure ü Required for skin incision/ Biopsy or Resp tract invasive procedure ü For dental procedures (manipulation of gingiva, Mucosa)

MITRAL STENOSIS: • Most common cause RHD • Primarily affects females • Diffuse thickening

MITRAL STENOSIS: • Most common cause RHD • Primarily affects females • Diffuse thickening of mitral leaflets & subvalvular apparatus, Calcification • Gradual progression (over 20 -30 yrs) • Other causes: Carcinoid syndrome, LA myxoma, Severe mitral annular calcification, RA, thrombus formation, SLE, congenital

Decreased mitral valve orifice Mechanical obstruction to LV diastolic filling Dec LV volume Dec

Decreased mitral valve orifice Mechanical obstruction to LV diastolic filling Dec LV volume Dec S. V. Inc LA volume & pressure Inc Pulmn Venous Pressure RV Hypertrophy & failure Overt Pulmn Edema Pathophysiology of Mitral Stenosis

 • Diagnosis: üClinical signs: opening snap (in early diastole), rumbling diastolic heart murmur

• Diagnosis: üClinical signs: opening snap (in early diastole), rumbling diastolic heart murmur Venous thrombosis (stasis, decreased activity) üCXR: -LA enlargement (straightening of left heart border, elevation of left main stem bronchus, double density of LA) -Mitral calcification -Evidence of pulmn congestion üECG: Broad notched P wave (P mitrale), AF

üEcho: (Anatomical details: Leaflet thickening, calcification, changes in mobility, chamber dimension, thrombus) Severity assessed

üEcho: (Anatomical details: Leaflet thickening, calcification, changes in mobility, chamber dimension, thrombus) Severity assessed by: - Mitral valve area, TVPG Also for Pulmn HT, Ventricular function

 • Treatment: ü Mild MS: Diuretics ü In AF: Beta blockers, Ca #,

• Treatment: ü Mild MS: Diuretics ü In AF: Beta blockers, Ca #, Digitalis (H. R. control) Anticoagulants (Warfarin to get INR of 2. 5 to 3) ü Surgical correction: • Percutaneous valvotomy • Valve reconstruction • Valve replacement, surgical commisurotomy

 • Management of Anaesthesia: üAvoid tachycardia (prevents filling) üAvoid decrease in SVR (use

• Management of Anaesthesia: üAvoid tachycardia (prevents filling) üAvoid decrease in SVR (use vasopressors which avoid Tachycardia) üDo no permit volume overload (can ppt CHF) üPrevent hypercarbia & hypoxemia, lung hyperinflation (Worsen Pulmn HT) üIf RVF : Requires ionotropic support & pulmonary vasodilators • Premedication: decrease anxiety (watch for resp depression), Continue drugs for HR control, Treat diuretic induced hypo. K+

Anticoagulant therapy (acc to minor or major procedure), coagulation tests for regional anaesthesia •

Anticoagulant therapy (acc to minor or major procedure), coagulation tests for regional anaesthesia • Induction: I/V agents (except ketamine), MR (which doesn’t Inc HR or Dec BP d/t histamine release) • Maintenance: Min effect on HR, SVR & PVR, contractility (N 2 O+ opioid+ Low conc Volatile agents) Reversal achieved slowly (to avoid tachycardia d/t glyco/atropine) Prevent light plane of anaesthesia (symp stimulation) Pulmonary vasodilator may be required Careful fluid replacement intraop (risk of Pulmn edema)

 • Monitoring: In asymptomatic (routine) Symptomatic/ major surgery (Intraarterial pressure monitoring, Pulmonary artery

• Monitoring: In asymptomatic (routine) Symptomatic/ major surgery (Intraarterial pressure monitoring, Pulmonary artery pressure, LA pressure: at higher risk of rupture of pulmn A so done carefully and less frquently, TEE) • Post operative management: Prevent fluid overload Manage pain (to prevent tachycardia, hypoventilation so hypoxia), neuraxial opioids May require mechanical ventilation (thoracic surgery)

MITRAL REGURGITATION: • In RHD, usually assoc with MS • Other causes: Papillary muscle

MITRAL REGURGITATION: • In RHD, usually assoc with MS • Other causes: Papillary muscle dysfxn, mitral annular dilatation, rupture of chordae tendinae, endocarditis, MVP, Congenital • Pathophysiology: Regurgitation into LA Dec LV stroke volume LA volume overload Pulmn congestion LA enlargement & AF

 • Regurgitant fraction depends on: ü Size of valve orifice ü Heart rate

• Regurgitant fraction depends on: ü Size of valve orifice ü Heart rate ü Pressure gradient across MV (SVR) • When MR develops gradually: LV becomes more compliant • When acute MR: No compensation, sudden sever Dec in S. V. l/t cardiogenic shock, with pulmn congestion • When MR+ MS : both volume and pressure overload Diagnosis: • O/E: holosystolic apical murmur, radiation to axilla • CXR: Cardiomegaly (LA & LV hypertrophy)

Diagnosis cont… • ECG: Lt axis deviation • Echo: Confirms MR, Anatomy (LA size,

Diagnosis cont… • ECG: Lt axis deviation • Echo: Confirms MR, Anatomy (LA size, LV wall thickness, cavity dimension), S. V. , LA appendage for thrombus • Doppler: Severity assessment (Calculation of regurgitant volume and fraction), area of regurgitant jet • Pulmn A. Occ. Pressure: Shows a ‘V’ wave in the waveform signifies regurgitation • Cardiac catheterisation: If surgery planned or severity doubtful • Coronary angiography: In elderly patients

Treatment: • Surgical: ü Mitral valve repair (preferred as apparatus preserved) ü Mitral valve

Treatment: • Surgical: ü Mitral valve repair (preferred as apparatus preserved) ü Mitral valve replacement Survival increased by surgery of performed before LVEF < 60%, or before End systolic LV dimension >= 45 mm Patients who do not improve with surgery: * LVEF < 30% * LV end systolic dimension > 55 mm • Medical : ü Vasodilators (Acute MR) ü Beta #, ACE inhibitors ü Biventricular pacing

Management of Anaesthesia: • Prevents which Dec C. O. • Maintain N to slightly

Management of Anaesthesia: • Prevents which Dec C. O. • Maintain N to slightly higher H. R. • Vasodilators to dec afterload • Ionotropes to improve LV contraction Induction: • I/V agent used • MR (pancuronium beneficial- raises HR) Maintainence: • Inhalational agents (Dec rise in BP & SVR caused by surgical stimulation) iso, des, sevo

 • Opioids (when severely compromised myocardial function) • Mechanical ventilation (allow venous return)

• Opioids (when severely compromised myocardial function) • Mechanical ventilation (allow venous return) • Maintain I/V volume Monitoring: • Asymptomatic / minor surgery (no invasive monitoring) • Severe MR (Pulmn A. Catherisation V wave)

MITRAL VALVE PROLAPSE: • Prolapsed one/ both mitral leaflets into LA during systole •

MITRAL VALVE PROLAPSE: • Prolapsed one/ both mitral leaflets into LA during systole • M. C. form of valvular ds. (young women) • With or Without MR • Causes: Marfan’s, RHD, Myocarditis, thyrotoxicosis, SLE Diagnosis: • Usually benign, but can l/t IE, cerebral embolisation, Severe MR, Severe dysrrhythmias, sudden death • C/F: Palpitation, anxiety, orthostatic symptoms, dysnea, fatigue, atypical chest pain

 • Echo: valve prolapse of 2 mm or more above mitral annulus With/

• Echo: valve prolapse of 2 mm or more above mitral annulus With/ without leaflet thickening (elderly/connective ts. ds) Functional form (mild bowing) Management of Anaesthesia: • Influenced by degree of MR • Basis: Larger LV will have lesser prolapse • Inc sympathetic activity • Dec SVR • Upright posture • hypovolemia Increase MR

 • Inc LV vol will Dec MVP (HTN/ Vasoconst, drug induced myocardial depression,

• Inc LV vol will Dec MVP (HTN/ Vasoconst, drug induced myocardial depression, volume resuscitation) Preoperative Evaluation: • Differentiate functional MVP from significant MR • Usually< 45 y, female • Beta blocker for arrhythmias (continued) • If H/O Transient neurological event with sinus rhythm, no atrial thrombi (pt usually on aspirin 81 -325 mg/d) • Pt with AF &/or with atrial thrombi or previous stroke (usually on warfarin) • ECG changes (PVC’s, QT prolongation) no implication

 • Pt may have systolic clicks, murmur even without symptoms (no need of

• Pt may have systolic clicks, murmur even without symptoms (no need of cardio consultation) • In older men (MVP can present with CHF) pt on diuretics, ACE inh Anaesthesia technique: • When LV function normal, tolerates both GA & regional Induction: • I/V agent (assess need to avoid dec in SVR) • Etomidate (min Myocardial depression) • Ketamine not to be used (Enhances LV emptying so inc MR) Maintenance: • Minimize sympathetic nervous system activity d/t surgical stimuli

 • Volatile anaesthetics with N 2 O +/- Opioids • Low dose: 0.

• Volatile anaesthetics with N 2 O +/- Opioids • Low dose: 0. 5 MAC (iso, des, sevo) in significant MR • Any MR (keep in mind vagolytic/ histamine induced effects) • Unexpected ventricular arrhythmias can occur intra op (Beta blocker or lignocaine) • Proper fluid balance • Vasopressors may be required • Avoid controlled hypertension technique (increases MVP) Monitoring: • Routine • Significant MR/ LV dysfunction (Pulmn A. catheter)

AORTIC STENOSIS: • Degeneration & calcification of leaflets (ageing), then stenosis • Causes :

AORTIC STENOSIS: • Degeneration & calcification of leaflets (ageing), then stenosis • Causes : Elderly, Bicuspid Aortic Valve • N valve area: 2. 5 -3. 5 cm 2 • Almost always assoc with some AR

 • Angina may occur despite absence of CAD (Inc myocardial demand, dec supply)

• Angina may occur despite absence of CAD (Inc myocardial demand, dec supply) • Syncope (fall in SVR can’t be compensated by inc C. O. ) Diagnosis: • C/F: angina, syncope, dyspnea on exertion • O/E: Systolic murmur best heard in aortic area (be careful as mostly patients undiagnosed) • CXR: Prominent ascending aorta • ECG: LV hypertrophy • Echo with doppler: Bileaflet aortic valve, thickening/ calcification of aortic valve, decreased mobility, LV hypertrophy

 • Echo cont… Valve area, TVPG • Cardiac Catheterisation • Coronary Angiography •

• Echo cont… Valve area, TVPG • Cardiac Catheterisation • Coronary Angiography • Exercise stress testing for Asymptomatic patients Treatment: • Asymptomatic: Continue medical therapy (delay Surgery untill s/s appear) • Aortic Valve replacement • Coronary revascularisation (if co-existant CAD) • Percutaneous aortic balloon valvuloplasty

Management of Anaesthesia: • Maintain N sinus rhythm • Avoid bradycardia/ tachycardia • Avoid

Management of Anaesthesia: • Maintain N sinus rhythm • Avoid bradycardia/ tachycardia • Avoid hypotension (if occurs aggressive Tt required) • Optimise I/V fluid volume CPR is generally ineffective in AS (Not enough CO generated) Induction: • GA preferred (regional causes Hypotension) • I/V agents used (ones which do not dec SVR) • If LV function compromised opioid induction

Maintenance: • Avoid drugs which suppress S. A. node (if occurs give atropine/ glyco/

Maintenance: • Avoid drugs which suppress S. A. node (if occurs give atropine/ glyco/ ephedrine) • If persistent tachycardia use esmolol • In supravent. tachycardias cardioversion to be done • Chanced of VT present (Lidocaine & defib) • If LV dyfxn (avoid drugs depressing myocardial contractility) • NM blocker with min hemodynamic effects • I/V fluid vol to be maintained Monitoring: • ECG, Intraarterial cath, P. A. cath, TEE

AORTIC REGURGITATION: • Causes: IE, RF, Bicuspid aortic valve, ds of root of aorta

AORTIC REGURGITATION: • Causes: IE, RF, Bicuspid aortic valve, ds of root of aorta

 • Magnitude of regurgitation depends on: ü Time available for regurgitation (H. R.

• Magnitude of regurgitation depends on: ü Time available for regurgitation (H. R. dependent) ü Pressure gradient across the valve (SVR dependent) Diagnosis: • C/F: Dysnea, orthopnea, fatigue, coronary ischemia • O/E: Diastolic murmur (Lt sternal border), bounding pulses, wide pulse pressure, Austin Flint murmur (low pitched diastolic murmur) • CXR & ECG: LV enlargement & hypertrophy • Echo: LVEF & ESV, Severity of regurgitation (on doppler) • Cardiac cath & MRI

Treatment: • Surgical: ü Replacement (even in asymptomatic) Immediate surgery in acute AR (as

Treatment: • Surgical: ü Replacement (even in asymptomatic) Immediate surgery in acute AR (as l/t sudden heart failure) ü Ross procedure (Pulmonic valve autograft) ü Valve reconstruction • Medical: ü Vasodilators (Nitroprusside) ü Ionotropes (Dobutamine) ü Long term Nifedipine/ Hydralazine

Management of Anaesthesia: • Avoid bradycardia (HR above 80/min), use atropine • Avoid inc

Management of Anaesthesia: • Avoid bradycardia (HR above 80/min), use atropine • Avoid inc in SVR • Minimize myocardial depression • If LV failure (vasodilators and ionotropes) • GA chosen Induction: I/V agent which doesn’t inc SVR or dec HR Maintenance: N 2 O + volatile agent &/or opioid • Iso, Des, Sevo good (inc HR, dec SVR, min myo depression) • If severe LV dysfunction high dose opioid (caution: bradycardia) • NM blocker: Pancuronium useful, modest tachycardia

Monitoring: • Minor surgery with asymptomatic ds. (routine) • Severe AR: ü Pulmonary A

Monitoring: • Minor surgery with asymptomatic ds. (routine) • Severe AR: ü Pulmonary A catheter ü TEE Useful for guiding I/V volume replacement, detecting myocardial depression, measuring response to vasodilators

TRICUSPID REGURGITATION: • Usually functional (d/t RV enlargement or Pulmn HT) • IE, Carcinoid,

TRICUSPID REGURGITATION: • Usually functional (d/t RV enlargement or Pulmn HT) • IE, Carcinoid, RHD, Ebstein anomaly • Mild TR in highly trained athletes Pathophysiology: • Regurgitation through TV RA vol Overload (but minimal rise in RA pressure) O/E: Raised JVP, Hepatomegaly, ascites, edema Tt: Tt the cause (improve lung fxn, relieve LV failure, dec PHT) Surgery (rarely for TR alone), Tricuspid annuloplasty/ valvuloplasty/ replacement

Management of Anaesthesia: • Keep CVP to high Normal • IPPV may decrease venous

Management of Anaesthesia: • Keep CVP to high Normal • IPPV may decrease venous return • Avoid hypoxemia & hypercarbia (to prevent inc Pulmn A. pressure) • N 2 O: weak Pulmn A. vasoconst (may inc TR) • Intra op measurement of RA pressure to guide fluid therapy • Very high LA pressure can l/t R L shunt (patent foramen ovale)

TRICUSPID STENOSIS: • M. C. cause: RHD (coexiztant TR, Mitral n aortic valve ds)

TRICUSPID STENOSIS: • M. C. cause: RHD (coexiztant TR, Mitral n aortic valve ds) • Inc RA pressure & pressure gradient b/w RA & RV PULMONARY REGURGITATION: • Secondary to Pulmn HT • Rarely symptomatic PULMONARY STENOSIS: • Usually congenital (detected and treated in early childhood) • C/F: Syncope, angina, RV Failure • Tt: surgical valvotomy

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