☛ RHD is still major problem in india.
☛ Incidence is decresing due to better socioeconomic condition.
☛ MS is mostly associated with MR , the morbidity is usually related to MS.
MVA 4-6 cm2
When there is stenosis
In La presence
☛ The stenosis develops progressively over the year.
☛ Most patients become symptomatic during mid trimester or in the post-partum period.
Cardiovascular changes in pregnancy
- Stroke volume ↑ed by 30%.
- HR ↑ed by 15-25%
- Cardiac output ↑ed by40-50%
- O2 consumption ↑es by 30-50%
- SVR ↓
- Intravascular volume ↑es 45%
- Diastolic BP ↓
- Systolic BP minimal or no change.
- All these cardiovascular changes are aqqrevated.
- In MS, asymptomatic patients tolerate the pregnancy well.
- The NYHA Gr 3 & 4 th patients have changes of developing pul. Edema & congestive heart failure.
- Because of increase in metabolic demands and increase cardiovascular changes, the pt graded according to NYHA clarification shifts to next class.
- Severity of MS is graded as follows.
|MVA||15.5- 2.5 cm2||1-1.5 cm2||< 1 cm2|
|Pressure gradient||< 5||5-15||> 15|
|Symptom||NYHA I Asymptomatic||NYHA II –III||III- IV|
Clinical feature -> HemodynamicS ->
- Most patients are asymptomatic.
- The symptomatypically start when MVA reduces to < 2cm2.
- At first, the left atrium tries to compensate for it by increasing the left atrial pressure & maintains the cardial output.
- Gradually as the stenosis worsens, left atrial pressure ↑es, the pressure gradients across MV ↑es without increasing the cardial output , LA undergoes dilatation.
- Due to back pressure changes, pulmonary venous HTN occur which is reactive, they transmit it to pulmonary artery & then gradually PAP increses & pulmonary hypertension develops.
- Because of pulmonary vascular resistance the Rt ventricle undergoes dilatation & ultimately fails.
- The atrium loses the contractility and goes into atrial fibrillation.
- Due to atrial fibrillation ,the systolic click is lost and cardial output further falls ,leading to worsening of the condition.
- The statics of blood in the left atrium leads to thrombus formation and can cause systemic embilisation
- The risk of maternal death is greatest during labour and during immediate post –partum period, due to auto transfusion from uterus flooding the pulmonary circulation.
- This auto transfusion continues till 24- 72 use after delivery.
- Most material deaths occurs in the post – partum period between 2 -9th
- Clinical Features ➔
- Fatigue, dypsnea, palpitatious.
- Generalized weakness, pallor, syncopal attack.
- Low volume pulse.
- pulse indicating atrial fibrillation.
- Mid diastolic Murmur.
- Opening snap.
- S3, S4 sound.
- LA hypertrophy –straightening of heart border .
- Small aortic knob – due to ↓ed cardiac output.
- Moustache / Antler sign – prominence of Upper Lobe vessels .
- Duble atrial shadow.
- Widening of carinal angle.
- Calcified MV.
- Pulmonary hemorrhage.
ECG : P mitrale
- Absenceof p wave- AF.
- Area of stenosis
- Associated lesions
- HTN .
- Presense of thronbus.
- Size of it atrium.
- Severity of lesions.
- Wilkins score can be calculated.
- Role of cardiac catheterization is limited & helpful when clinical & echo findings are not coinciding.
Predication of Mortality
- Correlates with NYHA class grading.
- NYHA class III & IV have highest mortality ranging from 5-15 % while class I & II < 1%.
- According to severity.
- Grade I
- Diuretics, o2, bed rest, Beta blockers.
- Prophylaxis for endocarditis.
- In presence of AF – Digoxin, Anticoagulation.
- Grade II: Above management + BMV / CMC/ MVR.
- Grade III : Surgical repair MVR /balloon valvuloplasty
- GRADE IV: Above + Antifailure management.
- Pts who are in AF require anticoagulants or who had MVR require it.
- Warfarin causes embrypathy that’s why avoided and given only during 12- 36 Wks of preg.
- First trimester & 36 Wks onwards -> unFractionated or LMW Heprin.
- Surgical management is best done is 2nd trimister of pregnancy.
- Open commissuotony is avoided as it is associated with high risk of fetal loss.
- Ballon mitral volvotomy is performed & with success rate of 100% without causing mitral regurgitation.
- In patient’s with calcified valve or severe MS, mitral valve replacement done, but Foetal loss may occour.
Obstetric Management and labour analgesia:
Advantages of labour analgesia
- Sympathetic of labour analgeria ➔
- Reduce acidosis
- Hypocarbia due to hyperventilation
- Material co – operation.
- Incordinated interine activity.
- Can be useful to cut short of 2nd stage of labour by forceps application or vacuum delivery
- Sudden drop of systemic vascular resistance can be avoided by epidural.
- Epidural can be extended if caesarian section is required.
- Radial artery annulations
- cvp monitoring
- Spo2 monitoring.
- Metal heart monitoring.
- O2 supplementation
- Hypotension – can be treated with insidious volume expansion and small doses of phenylephrine
- Maintain uterine displacement.
Method Of labour analgesia
- Continuous infusions by epidural
- CSE analgesia.
Anesthetic Management For Caesarians Goals
- Maintain sinus rhythm
- Avoid tachycardia and bradycardia
- Maintain SVR avoid precipitous fall
- Avoid rise in pul vascular resistance.