1 / 58

Aortic Stenosis in Pregnancy

Aortic Stenosis in Pregnancy. PMH- “Heart condition” since age 12 (no further follow-up) SOB and CP at rest and exertion worse over last two years PSH- none Medications- PNV Allergies- NKDA FH- unknown SH- no tobacco, EtOH or drug use. 18 year old G1P0 Spanish speaking female.

jersey
Download Presentation

Aortic Stenosis in Pregnancy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Aortic Stenosis in Pregnancy

  2. PMH- “Heart condition” since age 12 (no further follow-up) SOB and CP at rest and exertion worse over last two years PSH- none Medications- PNV Allergies- NKDA FH- unknown SH- no tobacco, EtOH or drug use 18 year old G1P0 Spanish speaking female

  3. Physical Exam • Vitals BP 104/62 HR 79 temp 36.6 RR 18 sat 100% • Height 4’10” Weight 99lbs. now 119lbs. • Heart– IV/VI systolic murmur… cresendo-decresendo murmur with no diastolic component, heard best at R upper sternal border, radiation to carotids bilaterally, no JVD, no 3rd or 4th heart sound • Airway– nml, Mal I • Lungs– CTA Bil., no w/r/r • Abd– NT gravid uterus, soft • Ext– no edema good pulses distally

  4. Labs: B positive BNP 5.5 WBC 8.71, Hg 12.5, Hct 36.8, Plts 256 Na 136, K 3.9, Cl 108, CO2 21, BUN 5, Cr 0.5, Glu 71 Ca 8.5 TSH 0.9, RPR, NR, HIV, VZ immune, RI, GC/ chlam, hep B all negative Plan: Admit to antepartum unit (social admission) to facilitate consultations by Maternal/Fetal Medicine, Cardiology, NICU and Anesthesiology.

  5. Cardiology • Murmur appreciated and echo performed: on 9/15 showing AS <.6cm2, probable bicuspid valve and EF 65%. • Pt followed for change in symptoms…. • Mid Oct. at about 35 wks. Gestation she complains of increased CP and SOB especially with exertion but also at rest. • .1%-1.4% pregnancies with clinically significant cardiac problems • Mortality from these .5%-2.7%

  6. Cardio cont’d • Echo shows peak gradient of 62mmHg and .58cm2 orifice by the continuity equation. • Velocity waveform is asymmetric which usually equates with less than severe stenosis. • CXR- WNL, no cardiopulmonary disease • CXR abnormalities may include enlarged aorta, cardiomyopathy and possibly pulm. edema

  7. Expected EKG changes with AS Left ventricular hypertrophy (LVH) • There are many different criteria for LVH. • Sokolow + Lyon (Am Heart J, 1949;37:161) • S V1+ R V5 or V6 > 35 mm • Cornell criteria (Circulation, 1987;3: 565-72) • SV3 + R avl > 28 mm in men • SV3 + R avl > 20 mm in women • Framingham criteria (Circulation,1990; 81:815-820) • R avl > 11mm, R V4-6 > 25mm • S V1-3 > 25 mm, S V1 or V2 + • R V5 or V6 > 35 mm, R I + S III > 25 mm • Romhilt + Estes (Am Heart J, 1986:75:752-58) • Point score system • Left atrial abnormality (dilatation or hypertrophy) • M shaped P wave in lead II • prominent terminal negative component to P wave in lead V1

  8. ? Suggestions for Anesthetic Plan • Anesthesia for Vaginal Delivery • Monitors for Vaginal delivery • Anesthesia for C/S • Monitors for C/S. • Maternal-Fetal Medicine, Cardiology , NICU, and Anesthesia develop working plan. • ***If possible, avoid C/S. If vaginal delivery, must avoid valsalva.

  9. Anesthesia for Vaginal Delivery • Neuroaxial anesthesia… • Continuous Spinal • Single shot spinal not reasonable for prolonged labor • Reliable block • Intrathecal narcotics avoid the sympathectic block with ensuing hypotension • Intrathecal narcotics not effective for second stage of labor. • Small doses of intrathecal LAs added to narcotics improve analgesia while limiting hemodynamic consequences. • Chance for spinal headache

  10. Anesthesia for Vaginal Delivery • Neuroaxial anesthesia… • Epidural • Pros…titratable to produce minimal hemodynamic changes, adequate anesthesia possible for vaginal or C-section, if performed properly no spinal headaches • Cons…higher failure rate compared with spinal

  11. Anesthesia for Vaginal Delivery • IV Narcotic analgesia (PCA) • Pros…would offer patient some analgesia (most still report 8-10/10 pain despite Fentanyl PCA) • Cons… Respiratory Depression (mother and fetus), Sedation (mother and fetus), N/V, decreased beat to beat variability on fetal heart rate tracing. • Cons….Would not effectively control the pain from second stage of labor and therefore would not attenuate the increase in HR associated with delivery.

  12. Stages of Labor • 1st stage – 2 phases: • latent phase encompasses the onset of pain to the first noticed change in cervical dilation • Maximal dilation phase…begins around 3 cm • 2nd stage – Maximal cervical dilation 10cm until delivery of fetus • 3rd stage – After delivery of fetus until delivery of placenta

  13. Board Questions?? • During the first stage of labor, the pain of uterine contractions is transmitted via spinal cord segments.. • A…T6 to L1 • B…T6 to L5 • C…T10 to L1 • D…T10 to S1 • E…T10 to S5 • Answer is….C

  14. Anesthesia for C-section • General anesthesia… • Pros…good airway control, minimal hemodynamic changes compared to epidural/spinal boluses to start case, can treat hemodynamic changes rapidly with close monitoring • Cons…possible difficult airway, aspiration risks, tachycardia and/or hypertension on induction or emergence, caution with volatile agents and hypotension or myocardial depression

  15. Hospital Course • Induced to L & D at 35 weeks. • Arterial line placed • Swan-Ganz catheter placed • Early epidural also placed by anesthesia • Continuous Telemetry monitoring • Pitocin was started on the night of 11/7 and by morning she was well dilated and contracting regularly

  16. 11/7 1950hrs: PCWP 10-11, CVP 5-7, good UOP 2330hr: PCWP 10-13 11/8 0100: PCWP 7-9…complains of CP 0300:CVP 15-16, trop .15 0500: PCWP 11-15, CO 5L/min 0800: trop <.1 (nml) Wedge maintained in above normal range Delivery at 1130am PCWP/CVP readings

  17. Hospital Course cont’d • No symptoms of AS during induction course. • Ready for delivery in AM with forceps • No valsalva by mother and epidural working well with slow dosing. • PCWP and urine output maintained throughout delivery with fluids and gentle epidural dosing.

  18. Hospital Course cont’d • After forceps delivery pt transferred to Step-Down on esmolol drip due tachycardia. • Drip stopped in CCU 11/8 and gentle diuresis started with Lasix. • Stable vital signs throughout hospital stay. • Day #3 post-forceps delivery patient transferred home with 6 week follow-up with cardiology for possible valve replacement.

  19. Physiologic Changes during pregnancy • Beginning to change at 5 weeks…10 fold increase in uterine blood flow at term • Cardiovascular : Blood volume 35%, CO 40-50%, SV 30%, HR 15-20% • Cardiovascular : SVR 15%, sys and diastolic BP 10mmHg • Pulmonary Changes: O2 consumption 20%, RR 15%, MV 50%, TV 40%, alv vent. 70% ERV 20%, FRC 20%

  20. Aortic Stenosis • In the past Rheumatic Valvular degeneration was the primary cause • Congenitally bicuspid valves become calcified and cause stenosis most commonly now…(1-2% of population) • Senile degeneration can also occur • 30% of patients older than 85 have significant changes • Risk for sudden death with AS increases when grad. >50mmHg and orifice less than .8cm2

  21. Normal Anatomy

  22. Aortic stenosis Anatomy

  23. AS 2D echo • Two-dimensional echocardiogram from a patient with aortic stenosis due to a bicuspid aortic valve (congenital). a. Parasternal long-axis view shows systolic doming (bowing) of the anterior and posterior cusps of the aortic valve (arrowheads). b. Parasternal short-axis view at the level of the aorta shows only two cusps (arrowheads). Ao, aorta; LVOT, left ventricular outflow tract; RVOT, right ventricular outflow tract; RA, right atrium; LA, left atrium; RV, right ventricle. • J.M. Felner M.D., R.P. Martin M.D., The Echocardiogram, The Hurst's The Heart, 8th ed., p 406. (modified)

  24. Symptoms • Rheumatic AS patients may remain asymptomatic for 40 years • Bicuspid valve patients will develop symptoms between 15-65 years of age • Calcifications of the valve usually occur after age 30 • THE TRIAD….

  25. The triad… • Any one of these symptoms being present is ominous and the patient’s life expectancy is less than 5 years… • ANGINA • SYNCOPE • CHF

  26. Angina • This is the initial symptom in 50-70% of patients. Most commonly occurring with exertion • May be present without CAD b/c of… • Increased myocardial O2 consumption, with increased myocardial thickness and increased afterload • Also increased LVEDP impairing flow to subendocardial layers

  27. Syncope • First symptom in 15-30% of patients • Once this occurs the average life expectancy is 3-4 years • Origin of syncope is controversial, however it may be related to uncompensated decrease in SVR with exercise

  28. CHF • Due to diastolic dysfunction (increased LV thickness) or systolic dysfunction (increased afterload or decreased myocardial contractility) • Once LV failure occurs the average life expectancy is 1-2 years • All AS patients are at increased risk of sudden death, as previously stated and…. • Only 18% of patients are alive 5 years after the peak systolic gradient is >50mmHg or the orifice <0.7cm2

  29. Pathophysiology • Stage 1: asymptomatic—mild stenosis • Normal stroke volume maintained as gradient between LV and aorta increases • Higher gradient results in concentric LV hypertrophy

  30. Pathophysiology • Stage 2: moderate stenosis—symptomatic • Dilation as well as hypertrophy occur in this stage • Decreased EF may be noted (due to decreased contractility) • Increased LVEDP and LVEDV leads to increased myocardial work and O2 consumption….at risk myocardium

  31. Pathophysiology • Stage 3: critical AS • Valve area is less than .5cm2/m2 and EF decreases further with further increases in LVEDP • Pulmonary edema when LA >25-30 mmHg • RV failure will develop if sudden death does not occur first

  32. Calculation of Stenosis • Gorlin equation: AV area (cm2)= CO (L/min)/ Mean pressure gradient1/2 This is the simplified version of the Gorlin equation (Hakki equation)

  33. Continuity equations • AV area=LVOT velocity/AV velocity x LVOT area ---LVOT calculation can have errors because it’s an area squared. • AV area= CO/(HR x systolic ejection period x 44.3 x gradient in mmHG1/2) ---Gorlin equation weak under low CO states • Hakki equation—based on the fact that HR x sys ejection period x 44.3= 1000; therefore AV Area= CO/ sq root of gradient (mmHg)

  34. PA Cath • Because of increased LVEDP stretching the mitral annulus a prominent v wave can be observed with disease progression. LA hypertrophy develops and the A wave becomes prominent • Example to follow on next slide…

  35. Arterial line • Pulsus parvus (narrow pulse pressure) • Pulsus tardus (delayed upstroke) • These features make the wave appear overdampened

  36. Hemodynamic profile • AS– increase LV preload and SVR • Decrease HR • Keep contractile force and PVR constant • Preload – because of Decreased LV compliance as well as Increased LVEDP preload augmentation is needed • (caution with nitro)

  37. Hemodynamics continued • Heart rate– no extremes of HR • Increase HR = decreased coronary perfusion • Sinus rhythm important for added EF • Contractility • avoid B-blockers they can increase LVEDP and decrease CO

  38. Hemodynamics continued • SVR– most of afterload is due to stenotic lesion, therefore it’s fixed. • If SBP is decreased the patient can develop subendocardial ischemia • Early alpha-adrengic agonists needed as treatment • PVR– this stays normal until very late in the disease process

  39. Toronto study • 1986-2000 of 49 pregnancies in women with AS • Mild AS (>1.5cm2 or grad<36mmHg) • Mod AS (1.0-1.5cm2 or grad 36-63mmHg) • Severe AS (<1.0cm2 or grad >63mmHg) • All women had functional NYHA class I or II disease when enrolled • 59% of patients, 29/49 had severe AS • Silversides C.K., Colman J.M., Sermer M., Farine D., Sui S. C., Early and intermediate-term outcomes of pregnancy with congential aortic stenosis. American Journal of Cardiology 2003;91:11

  40. NYHA functional classification • Class I – Asymptomatic • Class II – Symptoms with greater than normal activity • Class III – Symptoms with normal activity • Class IV – Symptoms at rest

  41. Toronto study continued • 10% of severe AS patients (3/29) had early cardiac complications (pulmonary edema or atrial arrhythmias)…no complications in mild/mod groups • One pt. had AVA .5cm2, peak gradient 112mmHg, she developed pulmonary edema at 12 weeks had emergent aortic valvuloplasty then had a Ross procedure 4 years after delivery • The second pt. had gradient of 104mmHg; she had postpartum hemorrhage, hypotension and subsequent pulmonary edema. Resection of her subaortic membrane was performed 17 months after delivery. • The third pt had a bicuspid valve AVA .7cm2, gradient of 64mmHg, she had atrial arrhythmias during antepartum period. She underwent a Ross procedure 18 months postpartum.

More Related