anaesthesia for valvular heart diseases made by: dr. meenal aggarwal moderator: dr. aparna
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Anaesthesia For Valvular Heart
Diseases
Made by: Dr. Meenal Aggarwal
Moderator: Dr. Aparna
Introduction
• Valvular ds: An increased burden on L or R ventricle
• Could be:
Pressure overload (Stenotic lesions)
Volume overload (Regurgitant lesions)
• Initially tolerated d/t compensatory mechanisms
Eventually cardiac muscle dysfunction
CHF ; even sudden death
Preoperative Assessment
• Aim: to know
Severity of Disease
Degree of impaired myocardial contractility
Presence of assoc. organ system diseases
• O/H: Symptoms:
Dyspnea, orthopnea, easy fatiguability
(Impaired myocardial contractility)
Anxiety, diaphoresis, resting tachycardia
(Compensatory increase in sympathetic activity)
Angina (d/t assoc CAD, or inc. myocardial O2 demand)
• Drug therapy:
Beta Blockers
Digitalis
ACE inhibitors
Vasodilators
Diuretics
Ionotropes
Antiarrhythmic drugs
Control HR (AS & MS: Allows diastolic filling)
Control BP and so dec. afterload (AR, MR)
Control of CHF
• O/E: Signs:
Inspection: Raised JVP
Auscultation: Basilar chest rales, S3, Murmurs
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
Dysrhythmias: AF (esp Mitral valve ds.) i.e. with enlarged Lt
atria
• Lab Investigations:
CXR:
o Size & shape of heart & great vessels
o Pulmonary markings
o Enlarged LA (Elevated Lt main bronchus, calcified valve)
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
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)
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 >
10mmHg, 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)
Tranthoracic Echo: To assess ring stability and leaflet motion
Transesophageal Echo: Better resolution
MRI: For prosthetic valve regurg, paravalvular leak
Cardiac Catheterisation: For TVPG, Effective valve area
• Complications of prosthetic valves:
Risk of thromboembolism (Anticoagulation)
Subclinical intravascular hemolysis
Risk of endocarditis (AB)
• Management of anti coagulation:
Can be continued in minor surgery with min blood loss
For major surgery (Stop warfarin 3-5 days preop, UF
heparin or LMWH started & continued upto day/ day before
of surgery, restarted post op)
Avoid elective surgery with in 1 month after an acute
thromboembolic episode
In pregnancy (TE prophylaxis to continue, S/C LMWH given +
low dose aspirin)
• Prophylaxis of Bacterial endocarditis:
Infection likely from frequent exposure to bacteremia
Weigh Risk to benefit ratio (AB resistance)
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 1st 6 months after procedure), Repaired
defects with residual defect)
4. Cardiac transplant pt who develop valvulopathy
AB prophylaxis not required for GU or GIT procedure
Required for skin incision/ Biopsy or Resp tract invasive procedure
For dental procedures (manipulation of gingiva, Mucosa)
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
Pathophysiology of Mitral Stenosis
Mechanical obstruction to LV diastolic filling
Decreased mitral valve orifice
Inc LA volume & pressureDec LV volume
Dec S.V. Inc Pulmn Venous Pressure
Overt Pulmn EdemaRV Hypertrophy & failure
• Diagnosis:
Clinical signs: opening snap (in early diastole), rumbling
diastolic heart murmur
Venous thrombosis (stasis, decreased activity)
CXR: -LA enlargement (straightening of left heart border,
elevation of left main stem bronchus, double density of LA)
-Mitral calcification
-Evidence of pulmn congestion
ECG: Broad notched P wave (P mitrale), AF
Echo: (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:
Mild MS: Diuretics
In AF: Beta blockers, Ca #, Digitalis (H.R. control)
Anticoagulants (Warfarin to get INR of 2.5 to 3)
Surgical correction:
• Percutaneous valvotomy
• Valve reconstruction
• Valve replacement, surgical commisurotomy
• Management of Anaesthesia:
Avoid tachycardia (prevents filling)
Avoid decrease in SVR (use vasopressors which avoid
Tachycardia)
Do no permit volume overload (can ppt CHF)
Prevent hypercarbia & hypoxemia, lung hyperinflation
(Worsen Pulmn HT)
If RVF : Requires ionotropic support & pulmonary
vasodilators
• Premedication: decrease anxiety (watch for resp depression),
Continue drugs for HR control, Treat diuretic induced hypoK+
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 (N2O+
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 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 dysfxn, mitral annular dilatation,
rupture of chordae tendinae, endocarditis, MVP, Congenital
• Pathophysiology:
Dec LV stroke volume
Regurgitation into LA
LA volume overload
LA enlargement & AFPulmn congestion
• Regurgitant fraction depends on:
Size of valve orifice
Heart rate
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, 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:
Mitral valve repair (preferred as apparatus preserved)
Mitral valve replacement
Survival increased by surgery of performed before LVEF < 60%, or
before End systolic LV dimension >= 45mm
Patients who do not improve with surgery:
* LVEF < 30% * LV end systolic dimension > 55mm
• Medical :
Vasodilators (Acute MR)
Beta #, ACE inhibitors
Biventricular pacing
Management of Anaesthesia:
• Prevent events 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)
• 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
• 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 2mm 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, 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 81-325mg/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 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 N2O +/- 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 : Elderly, Bicuspid Aortic Valve
• N valve area: 2.5-3.5 cm2
• Almost always assoc with some AR
• 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
• 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 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/ 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
• Magnitude of regurgitation depends on:
Time available for regurgitation (H.R. dependent)
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:
Replacement (even in asymptomatic) Immediate surgery in
acute AR (as l/t sudden heart failure)
Ross procedure (Pulmonic valve autograft)
Valve reconstruction
• Medical:
Vasodilators (Nitroprusside)
Ionotropes (Dobutamine)
Long term Nifedipine/ Hydralazine
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: N2O + 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:
Pulmonary A catheter
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, 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 return
• Avoid hypoxemia & hypercarbia (to prevent inc Pulmn A.
pressure)
• N2O: 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)
• 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
Thank You
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