mitral stenosis anaesthetic implications

1. Anaesthesia for Pregnant patient
with Mitral Stenosis
Speaker : Dr.Sushma,
Dr. Shiva krishna,
Moderator : Dr. Ananya
Dr.Gopinath
ESIC HOSPITAL ,SANATHNAGAR 1

2. TOPICS
• Mitral valve anatomy
• Mitral stenosis pathophysiology
• Physiological changes of pregnancy
• Pregnancy with MS
Medical management
Surgical management
 Management of PBMV
 Management of Cardiac surgery on CPB
Case scenarios

3. Mitral valve anatomy
3

4. Mitral stenosis
• Incidence : 25% of all rheumatic valvular lesions.
• Approximately 25% of women with mitral stenosis first experience symptoms
during pregnancy.
Etiology :
• Rheumatic fever
• congenital defects
• Atherosclerosis
• Lutembacher's syndrome
4

5. Mitral stenosis–Pathology
Thickening and commissural fusion of the mitral valve leaflets.
Increased rigidity of the valve leaflets
Thickening, fusion and contracture of the chordae and papillary heads
Calcification of the valve apparatus
Obstruction at the level of the mitral valve
5

6. Mitral stenosis- pathophysiology
Obstruction at the level of the mitral valve
raised left atrial pressure enlargement of left atrium
pulmonary hypertension Atrial fibrilaltion
right heart failure
6

8. Tricuspid Regurgitation
RA Enlargement
Hepatic Congestion
JVD
LA Enlargement, ↑LA
Pressure
LA Thrombi
Atrial Fib
,Ortners-RLN ,Lt bronchus
,Oesophagus
↑Pulmonary HTN
Pulmonary Congestion
RV Pressure Overload
RVH
RV Failure LV Filling
Fixed CO

9. Clinical features
Symptoms
• Dyspnea
• Paroxysmal nocturnal
dyspnea
• Orthopnea
• Palpitations
• Hemoptysis
• Chest pain
Signs
• Mitral facies
• Raised JVP
• Parasternal heave
• Tenderness right hypochondrium
• Ascites
• Diastolic murmur
• Accentuated 1st heart sound
(wide, loud, split first heart
sound, an S3 sound, and a soft
systolic ejection murmur in
pregnants)
• Opening snap
9

10. Grading of MS
10

11. PV-loop in MS
11

12. Gorlin’s equation
The relationship between cardiac output,
valvular area & transvalvular gradient can be
expressed by the Gorlin equation:
12

14. Prediction Of Mortality & Morbidity
• Correlate well with the NYHA functional classification.
• Cardiac complications occurs in 35% of the pregnancies.
• Maternal cardiac complications ∝ severity of the mitral
stenosis
 As Pregnacy aggravates Mitral stenosis
o Mild MS in Non pregnant patient will become Moderate MS in
Pregnancy
o Moderate  Severe
o Severe  critical

17. Physiological changes during
pregnancy in CVS
17

18. Abnormal clinical findings in normal
pregnancy
• Palpitations (↑ blood volume, displacement of heart)
• Loud S1 with exaggerated splitting of mitral & tricuspid components
• Systolic murmur in apex & pulmonary area
• Murmur in left 3rd & 4th ICS
• S3 – rapid diastolic filling of left ventricle, S4
ECHO:
• LVH by 12 weeks gestation, with a 50% ↑ in mass at term.
• ↑ LV end diastolic diameters
• ↑ left and right atrial dimensions
18

19. Stroke volume & heart rate
Heart rate:
 1st trimester  ↑15%
 2nd trimester ↑ 25%
 3rd trimester  remains same as 2nd trimester
Stroke volume:
 5th to 8th week of gestation ↑ 20%
 2nd trimester ↑25% to 30%
 until term  remains at that level
19
Clinical implication:-
↑HR will ↓ diastolic
filling time will further
↓ EDV
Implication :-”MS is fixed Cardiac output”condition

20. Cardiac output
• 5 weeks  begins to increase
• 1st trimester of pregnancy  35% to 40%
• 2nd trimester ↑50%
20

21. Blood pressure
• Systolic BP: not much effected
• Diastolic BP: early- to mid-gestational ↓20%.
Causes for ↓ DBP:
 Low resistance intervillous space
 Vasodilating effects of progesterone, estrogen &
prostacyclin
• MAP: not much effected
21

22. Haemodynamics at term gestation
22

23. Haemodynamics during labor
23

24. Graphical representation of
haemodynamics in pregnancy
24

25. Haemodynamics during puerperium
25

26. Hematological changes in pregnancy
Parameter Change Amount
Blood volume Increase 45 %
Red cell volume Increase 30%
26
Coagulation factors in pregnancy

27. Pregnancy with mitral stenosis
27

28. Incidence & Mortality
• Cardiac disease in pregnancy: 0.1-4%
• Rheumatic mitral stenosis forms 88% of the heart
diseases complicating pregnancy.
• The maternal mortality for parturients with MS
with NYHA class III & IV is 6.8% as compared to
0.4% for those in the NYHA class I and II
28

29. Why pregnancy aggravate the
symptoms of mitral stenosis?
• Pregnancy with severe MS do not tolerate the cardiovascular demands
• All the physiological changes of pregnancy are against the haemodynamic goals of
MS
• Heart rate ↑ 20-30 % ↓ diastolic filling time of LV.
• ↓ SVR  peripheral pooling
• Caval compression –↓venous return (preload)
• ↑ Blood volume,autotransfusion  ↑ pulmonary capillary hydrostatic pressure
pulmonary edema
• ↑ O2 requirement
• Pregnancy+ MS+ AF ↑Atrial thrombus
 Convert the compensatory decompensatory stage. 29

30. Labor & postpartum period
Labor:
Pain  Sympathetic stimulation  tachycardia
Uterine contractions  autotransfusion  ↑
blood return to LA  pulmonary edema
Immediate post partum
Autotransfusion & IVC de-compression 
sudden ↑ in the preload flooding the central
circulation severe pulmonary oedema.
30

31. Autotransfusion:
 Uterine involution  release of IVC compression
 ↓ intervillous space  ↓ venous capacitance
• There continues to be autotransfusion of blood for 24–72 hr after
delivery The risk of pulmonary oedema extends for several days
after delivery.
• Risk of maternal death  greatest during labour & the immediate
post-partum period.

32. What are the risks to fetus ?
• Growth retardation
• Preterm delivery
• Low birth weight
• Respiratory distress
• fetal / neonatal death
32

33. Pre op optimization
• Bed rest in left lateral position
• Decrease pulmonary congestion: diuretics (Use of diuretics may be
reasonable for pregnant patients with MS and HF symptoms- AHA
2014)
• O2 therapy if patient had CHF- during decongestion therapy for
supportive care.
• β-adrenergic receptor blockade is useful to prevent tachycardia during
pregnancy.
• Metoprolol has a lower incidence of fetal growth retardation than
atenolol and is the preferred beta blocker for use in pregnancy. (AHA
2014)
33

34. • Use of β blockers as required for rate control is reasonable
for pregnant patients with MS in the absence of
contraindication .
• The use of β- blockers with β-1 selectivity is preferred
because the β-2 effects on uterine relaxation are avoided.
(AHA 2014)
• Antibiotic prophylaxis for endocarditis is reserved only for
patients with a previous history of endocarditis / presence
of established infection.

35. Management of Acute AF (<48 hrs)
• Anticoagulation should be given to all pregnant patients with MS &
AF. (AHA 2014)
• Rx atrial fibrillation:
– Digoxin,β blockers,cardioversion
• Haemodynamically unstable (Decompensated HF ):
hypotension/heart failure/chest pain/syncope
- DC Cardioversion ( with FHR monitoring), Digoxin
• Haemodynamically (compensated HF) stable :
 Rate control - β blockers
 Anticoagulant

36. Standard anticoagulation therapy
during pregnancy
SC/IV heparin/LMWH for up to 12 weeks antepartum (aPTT 1.5–
2.5-times of normal)
 Warfarin from 12 to 36 weeks (maintain INR 2.5–3.0) ,
SC/IV heparin,LMWH after 36 weeks

37. Pregnant patient with MS
Obstetric procedures Non Obstetric procedures
1.Termination of pregnancy
2.Labour & NVD
3.Caeserean section
Cardiac Non cardiac
1.BMV
2.CMC
3.OMC
4.MVR Emergency Non emergency
( appendicitis) (brain tumors)
37

38. Pregnant patient with MS
1st
trimester
MTP
Emergency Sx
2nd
trimester
Cervical encirclage
Elective sx(cardiac &
non-cardiac)
Emergency Sx
3rd
trimester
NVD
LSCS
Emergency Sx

39. Anaesthetic goals
Pregnancy associated
change
Haemodynamic goal measures
tachycardia Avoid tachycardia Analgesia during labor
Aortocaval compression Optimal preload Wedge under right hip
Drop in SVR Maintain or Minimise
decrease in SVR
Avoid sympathetic block
(avoid neuraxial block)
Maintain or Minimise PVR Avoid pain, hypoxia,
hypercapnea

40. Obstetric management
Monitors:
 Invasive hemodynamic monitors,I/O monitoring.
 Fetal heart rate monitoring
Special measures:
 Continuous O2 supplementation throughout labor
 Avoid aorto-caval compression(wedge placement )
 Monitor intravascular fluid status(CVP,PA)
 Rx tachycardia with β blockers
 Avoid bolus administration of oxytocin, PGF2 α /methylergometrine (↑PVR)
40

41. Labor analgesia -1st Stage
 Epidural analgesia with 0.125% bupivacaine + fentanyl 2mics/ml during
active labor & immediate postpartum period (to prevent tachycardia,
pulmonary edema)
or
 Intrathecal opioid followed by epidural local anesthetic infusion
– Avoid test dose
– Avoid preloading
– Phenylephrine for hypotension(1-2 mcg/kg)
– Esmolol for rate control - 500 mcg/kg IV as a bolus dose over 1 min f/b maintenance
infusion of 50 mcg/kg/min IV for 4 minutes
41

42. 2nd stage of labour
• Assisted Vaginal Delivery
• only the uterine contractile force should be allowed rather
than the maternal expulsive effort that is always associated
with the valsalva maneuver
• Continue epidural infusion with S2- S4 as the desired level
• Pudendal nerve block.
• Avoid trendelenberg
42

43. • After delivery of the foetus slow infusion of oxytocin.
• Rapid infusion of oxytocin can ↓ SVR as well as ↑ PVR,
resulting in a drop in cardiac output.
• Methylergometrine / Carboprost , produces severe
hypertension, tachycardia and ↑ PVR
• Hemodynamic compromise & pulmonary edema during
the postpartum period mandates the need for intensive
care monitoring in the post partum period
43

44. Cesarean section
Advantages:
• Avoids hemodynamic consequences of labour.
 Choice of anesthesia for CS depends on:
 No controlled studies examining the best type of anaesthetic technique in these
patients and guidelines and standards are lacking.
 Severity of MS
 Emergency/Elective
 Hospital facilities-Invasive monitors,Ventilator,ICU,cardiac facilities,Surgeons.
44

45. Neuraxial block
• A single-shot spinal anesthesia is contraindicated in severe stenosis
because of uncontrolled hypotension.
– ↓ SVR
– ↓ cardiac preload
– reflex tachycardia
• In mild –moderate cases spinal anesthesia with 1ml 0.5% bupivacaine
and 10-20mcg fentanyl along with epidural block or use of spinal
catheter .
• Small boluses of phenylephrine (25-50mcg) are effective in avoiding
precipitous hypotension.
45

46. Epidural block
• Epidural alone can be used in mild to moderate MS .
• A well-controlled, individualized epidural neuraxial block using
incremental graded dosing of local anesthetic in the hands of
experienced anesthesiologists with invasive monitoring of arterial
& CVP may be beneficial even for the most severe cardiac disease.
• Sensory level to be achieved with titrated doses of LA .
• Optimize fluid status
• Avoid adrenaline in the epidural test dose
46

47. Advantages of graded epidural
analgesia
• Administered in incremental doses & total dose can be
titrated to the desired sensory level.
• Slower onset - allows the maternal CVS to compensate for
the occurrence of sympathetic blockade  Low risk of
hypotension & Low risk of↓ uteroplacental perfusion .
• Segmental blockade spares the lower extremity “muscle
pump,” aiding in venous return.
• ↓ incidence of thrombo-embolic events.
47

48. General anaesthesia
• Modified rapid sequence induction using Etomidate, Remifentanyl & Sch is an
ideal choice in tight stenosis with pulmonary hypertension.
• Inhalational agents may be added to prevent awareness.
• A β-blocker & opioids should be administered before / during the induction
of GA.
• Maintenance of anaesthesia with O2 & Air 50:50, sevoflurane, opioids &
vecuronium.
• Phenylephrine (0.5 -1 mcg/kg) boluses with restricted fluid therapy may be
used for management of hemodynamic instability.
• Invasive haemodynamic monitoring, FHR monitor
48

49. Avoid drugs that cause tachycardia
 Atropine
 Ketamine
 Pancuronium
Treatment
• Esmolol has a rapid onset and short duration of action, it is
a better choice in controlling tachycardia.
• Fetal bradycardia has been reported after esmolol, foetal
heart rate should be monitored.

50. General anaesthesia- disadvantages
• Raises pulmonary arterial pressure
• Tachycardia during laryngoscopy and tracheal
intubation,extubation.
• Adverse effects of positive-pressure ventilation
on the venous return may ultimately lead to
cardiac failure.
• Risk of aspiration.
50

51. Surgical management
Non obstetric Options:
 Percutaneous balloon mitral valvotomy (PBMV)
 Closed mitral commissurotomy (CMV)
 Open mitral commissurotomy (OMV)
 Mitral valve replacement (MVR)
• PBMV is preferred over CMC / open procedure with CPB.
• PBMV is better than CMC in terms of valve area & long term
durability .
51

53. PBMV
• Percutaneous mitral balloon commissurotomy is reasonable for
pregnant patients with severe MS (mitral valve area <1.5 cm2) with
valve morphology favorable for PBMV who remain symptomatic with
NYHA class III to IV HF symptoms despite medical therapy. (AHA 2014)
• Best performed after 20th week of gestation.
• Procedural time should be shortest possible .
• Abdominal shield to reduce radiation risk.
• Patient should be explained about the radiation risk to fetus.
• TEE guidance aids to reduce radiation
53

54. • Percutaneous mitral commisurotomy has edge over medical
management in patients with MVA < 1.0cm2
Decision to perform PBMV depends on (Wilkins score <8)
1. Valve area
2. Symptoms
3. Exercise tolerance
4. Adequate leaflet mobility with little calcification.
54

55. PBMV not preferred :
 presence of clot in LA
 severe leaflet calcification
 leaflet thickening,
 Immobility
 subvalvular fusion
 Commissural calcification
• Complication:
Mitral regurgitation represents the most common complication associated with
commissurotomy.
55

56. Anesthetic management of Balloon
valvuloplasty
• Best obtained in an awake state with minimal dose of opioids to
avoid fetal bradycardia & apnea in the pregnant patient.
• Intravenous sedation/ regional anesthesia is preferred over GA for
non-obstetrical procedures in pregnant patients because:
 aspiration risk with GA
 difficult airway management with difficult endotracheal intubation
can be avoided.
 minimizes fetal exposure to the potent anesthetic agents.
56

57. Closed mitral commisurotomy
• Practiced mostly in developing countries
Disadvantages include :
Uncontrolled procedure ( may cause MR)
Subvalvular deformity cannot be corrected
Risk of general anesthesia
57

58. Open commisurotomy
Advantages over MVR include :-
• Avoids risk of prosthetic valve
• Avoids need for anticoaguation
• Valve can be conserved
58

59. Mitral valve replacement
• Valve intervention is reasonable for pregnant patients with
severe MS (mitral valve area <1.5 cm2)
• valve morphology not favorable for PBMC  only if there
are refractory NYHA class IV HF symptoms. (AHA 2014)
• Valve operation should not be performed in pregnant
patients with valve stenosis in the absence of severe HF
symptoms. (AHA 2014)
59

60. APPENDICECTOMY
• Common in 2nd and 3rd trimester
• In pregnancy appendix lies above the iliac crest.
Concerns:
 CO2 insufflation- hypercarbia risk of pulmonary
hypertension
 Elevated intraabdominal pressure lowers venous return
& uteroplacental blood flow
60

61. Laparoscopic surgery
Advantages
• Less post op pain
• Early mobilization lesser
thromboembolic events.
• Lesser incidence of infection
• Decreased rate of fetal
depresion due to less
narcotic use
Disadvantages
• Technically difficult after 26
wks
• Trochar insertion
difficulty/Trauma
• ↑intra abdominal pressure 
utero placental blood flow↓,
Fetal hypotension,
• Risk of uterine
irritationuterine
manipulation,cautery
• Fetal acidosis due to CO2
narcosis.

62. CPB In Pregnancy

63. Cardiac surgery in Pregnancy
• Mortality in pregnant with MS is ↑ when compared
to non-pregnant patients with MS .
• Fetal mortality is 20-30%
• The period between the 20th and 28th weeks of
pregnancy appears to be safest for the fetus .(AHA
2014)
• CS should precede valvular surgery if fetus is viable.
63

64. Fetal risk in CPB is High because of ?
• Hypothermia uterine contraction ↑
• Hypothermia should be avoided
• Placental hypoperfusion bradycardic response
in fetus
• CPB is avoided in 1st trimester due to high risk of
teratogenecity.
64

65. Strategies during cardiopulmonary bypass to improve feto-maternal outcomes
(PaO2-150mm Hg)

66. Tocolytics
Beta agonist: Ritoridine, forneterol
Calcium channel blockers: Nifedipine
Oxytocin Antagonist: Atosiban
MgSo4.
Inhalational anaesthetics-Halothane
Miscellaneous:nitrates, progesterone,
indomethacin

67. Uterine & Fetal Monitoring During CPB
Cardiotocography-Monitoring uterine activity & fetal heart
rate  information regarding placental blood flow &
perfusion.
•Monitor fetal heart beats from the surface of maternal
abdominal wall.
Disadvantage :-Difficult to maintain in place during the
procedure.
•Transvaginal probe to monitor fetal heart beats & umbilical
cord flow.

68. Pregnant with prosthetic valve
• TTE should be performed in all pregnant patients with a prosthetic valve if not
done before pregnancy.
• Also in ,patients who develop symptoms (prosthetic valve obstruction /
embolic event)
• Prosthetic valve thrombosis accounts for mortality of 1- 4 % in pregnants.
Anticoagulation:
• Therapeutic anticoagulation with frequent monitoring is recommended for all
pregnant patients with a mechanical prosthesis
• Asprin 75-100 mg reasonable in patients with bioprosthetic mitral valve
Matiasz R, Rigolin VH. 2017 Focused Update for Management of Patients With Valvular Heart Disease:
Summary of New Recommendations. J Am Heart Assoc
68

70. Bhagra CJ, et al. Heart 2017;103:244–252. doi:10.1136/heartjnl-2015-308199

71. • LMWH :
Increased risk of valve thrombosis & embolic
events
Require monitoring of anti-Xa levels
• Disadvantages of intravenous UFH
Increased risk of serious infection due to IV
cannulation
Osteoporosis .

72. Labor analgesia for pregnants on
anticoagulation
Epidural, blocks  ↑ INR  Contraindicated
Entonox pulmonary pressures ↑
IV opioids ( remifentanyl) are the choice

73. Conclusion
Better understanding of the physiology of
pregnancy & its effect on mitral stenosis as a
whole is a prerequisite to achieve better
results.

74. References
• Kaplan’s Cardiac Anesthesia; 5th edition
• Miller’s Anesthesia; 7th edition
• Clinical Anesthesia; Barash, Cullen, Stoelting,
5th edition
• Stoelting’s Anesthesia & Co-existing Disease;
5th edition

75. Case scenarios
75

76. Mild MS in labor
Plan of anaesthesia
• Epidural : 0.125% bupivacaine + fentanyl 25 mics (avoid adrenaline in test dose)
Level of Epidural placement ?
• L2-L3/L3-L4
Dermatomal level to be blocked by Epidural?
 Stage1 : T10 to L1
 Stage 2: S2 to S4
Precaution for 2nd stage of labour?
• Cut short stage 2 with forceps/ ventouse
76

77. Moderate MS for elective caesarean
section
• Graded epidural
• Epidural+GA
• CSE in experienced hands(mini spinal )
77

78. • 25 yrs female with 36 weeks of gestation with
Moderate MS with no signs of Heart Failure
for emergency caesarean section (fetal
distress) in tertiary care hospital .
• Plan of Anaesthesia?
• General anesthesia (no time for graded
epidural)
• Rapid sequence intubation
• TAP block/local infiltration
78

79. Cont..
• Sudden increase in airway pressure intraoperatively &
associated hypotension & tachycardia ?
• Pulmonary edema-pain,autotransfusion
• Rx :
 Correct tachycardia to improve LV filling :
 Increase depth off anesthesia
 Iv esmolol
 Iv phenylephrine
 PEEP
 Loop diuretics
 Head end elevation

80. Cont..
• Patient after successful LSCS under GA with TAP block ,
2hrs after extubation complaining of SOB Grade-IV with NO
pain .
• Vitals -BP-100/60mm Hg,
Hr-100/min.
Spo2-98% on Face mask,
RR-29/min.
ABG-pH-7.28,pCo2-50mmHg,pO2-58mm Hg?
Post delivery pulmonary edema
• Positive pressure ventilation-NIV
• Balloon mitral valvotomy/MVR
80

81. • 27yr female with 34 weeks of gestation S/P Mitral valvular
replacement (“mechanical”)on vitamin K antagonist
,presented with decreased fetal movements (fetal distress)
in early stage of labour.On examination.....
• Hemodynamics-stable
• ECHO –normal findings
• Plan of anaesthesia for Labour,LSCS?
81

82. • 20yr female patient with 20 weeks of gestaion with
moderate MS diagnosed to have acute cholilithiasis
,planned for laparoscopic cholicystectomy under GA
• Immediately after starting surgery patient developed
hypotension ,bradycardia ,airway pressures increased.
• Immediate Plan of management ?

83. • 24 yrs female with 20 weeks of gestation with
abdominal pain diagnosed to have acute
appendicitis.
• Hemodynamics-Stable
• Plan of anaesthesia?