Pregnancy with mitral stenosis final

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

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

8. 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 1 st heart sound (wide, loud, split first heart sound, an S3 sound, and a soft systolic ejection murmur in pregnants ) Opening snap 9

9. Grading of MS 10

10. PV-loop in MS 11

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

12. 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 Mild MS in Non pregnant patient will become Moderate MS in Pregnancy Moderate  Severe Severe  critical

13. Physiological changes during pregnancy in CVS 17

14. 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 3 rd & 4 th 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

15. Stroke volume & heart rate Heart rate: 1 st trimester  ↑ 15% 2 nd trimester  ↑ 25% 3 rd trimester  remains same as 2 nd trimester Stroke volume: 5 th to 8 th week of gestation  ↑ 20% 2 nd 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

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

17. 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

18. Haemodynamics at term gestation 22

19. Haemodynamics during labor 23

20. Graphical representation of haemodynamics in pregnancy 24

21. Haemodynamics during puerperium 25

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

23. Pregnancy with mitral stenosis 27

24. 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

25. 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

26. 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

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

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

29. 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

30. 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.

31. 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

32. 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

33. 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

34. Pregnant patient with MS

35. 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

36. 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

37. Labor analgesia -1 st 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

38. 2 nd 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

39. 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

40. 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

41. 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

42. 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

43. 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  L ow risk of hypotension & L ow risk of ↓ uteroplacental perfusion . Segmental blockade spares the lower extremity “ muscle pump , ” aiding in venous return. ↓ incidence of thrombo -embolic events. 47

44. 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

45. 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.

46. 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

47. 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

48. 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 20 th 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

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

50. 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

51. 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

52. 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

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

54. 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

55. APPENDICECTOMY Common in 2 nd and 3 rd 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

56. 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.

57. CPB In Pregnancy

58. 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

59. 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 1 st trimester due to high risk of teratogenecity . 64

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

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

62. 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 .

63. 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

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

65. 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 .

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

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

68. 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

69. Case scenarios 75

70. 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 2 nd stage of labour? Cut short stage 2 with forceps/ ventouse 76

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

72. 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

73. 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

74. 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

75. 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

76. 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 ?

77. 24 yrs female with 20 weeks of gestation with abdominal pain diagnosed to have acute appendicitis. Hemodynamics -Stable Plan of anaesthesia?