Document 6427593

The pregnant cardiac patient
When should I worry ?
I A Joubert
Department of Anaesthesia
Department of Critical Care
University of Cape Town
ASM - Rotorua, November 2009
How common is this ?
• Between 0.1 and 4% of pregnancies
• International differences –
– Less common in developed world
•
•
Steady decline in rheumatic heart disease
More correction of congenital lesions
• Mortality reduced since 1950
– From 5.6 to 0.3 per 100 000 births
Why Mothers Die 1997–1999. The Confidential Enquiries into Maternal Deaths in the United Kingdom.
RCOG, 2001; 153–64
But it is important …
• Accounts for –
– 16.5% of all maternal deaths !
• 40% of patients have inadequate care !
Deans CL, Uebing A, Steer PJ. Cardiac disease in pregnancy. Progress in Obstetrics and Gynaecology,
Vol 17, 2007, 164-182.
Why the problems ?
• Pregnancy increases physiologic demand
– 30 – 50% increase in blood volume
– 30 – 50% increase in cardiac output
• Stroke volume increases early on
• Heart rate increases later
(25 – 30%)
Hunter S, Robson SC. Adaptation of the maternal heart in pregnancy. British Heart Journal
1992;68:540-3
Big trouble !
Non-viable
Congestion Overt failure
Other important changes …
• From the pulmonary perspective –
– Steady
– Steady
decrease in colloid oncotic pressure
increase in hydrostatic pressure
• Pregnant patients are prone to –
– The development of pulmonary oedema !
More importantly …
• Colloid oncotic pressure is lowest –
– Between 6 and 16 hours post-partum
– This is when pulmonary oedema occurs !
The bottom line …
• Cardiac disease –
– Causes morbidity and mortality
• Physiologic demand –
– Responsible for timing of presentation
• Pulmonary oedema a big problem
– Particularly post delivery !
Also confounding the issue …
• Most pregnant patients –
– Have symptoms of cardiac disease
•
•
•
Fatigue
Dyspnoea and orthopnoea
Subtle abnormalities on examination
– Are all common !
Assessing risk …
How do we assess risk ?
• Poor functional status –
– NYHA III-IV or cyanosis
• Ejection fraction < 40%
• Left heart obstruction –
–
–
–
MV area of < 2.0 cm2
Aortic area of < 1.5 cm2
Gradient of > 30 mmHg
• Prior cardiac event
Siu SC, Sermer M, Colman JM, et al. Prospective multicenter study of pregnancy
outcomes in women with heart disease. Circulation 2001; 104:515–521.
How do we assess risk ?
• Incidence of cardiac events –
– No risk factor
– One risk factor
– More than one factor
5%
25 %
75 %
• Identifying risk factors is important !
Siu SC, Sermer M, Colman JM, et al. Prospective multicenter study of pregnancy
outcomes in women with heart disease. Circulation 2001; 104:515–521.
Remember them !
• Poor functional status –
– NYHA III-IV or cyanosis
• Ejection fraction < 40%
• Left heart obstruction –
–
–
–
MV area of < 2.0 cm2
Aortic area of < 1.5 cm2
Gradient of > 30 mmHg
• Prior cardiac event
Siu SC, Sermer M, Colman JM, et al. Prospective multicenter study of pregnancy
outcomes in women with heart disease. Circulation 2001; 104:515–521.
Particular points to identify …
• A loud 4th heart sound
• Any diastolic murmur
• A systolic
of > 3/6
Thesemurmur
are always
abnormal !
• Fixed splitting of the 2nd sound
• An opening snap
Prasad AK, Ventura HO. Valvular heart disease and pregnancy. Postgraduate Medicine
2001;110:69-88
Issues during pregnancy
and labour
During pregnancy
• The single biggest goal –
– To maintain the patient within reserve
– Limitation of all physical activity
– Hypertension, anaemia and infection –
• Must all be treated aggressively
Anticoagulation may be needed
• Only heparin is absolutely safe
• Warfarin –
– From week 14 to middle of 3rd trimester
• LMWH may be practically easier
• Anticoagulation is safe 4 - 6 hours post delivery
Bates SM, Greer IA, Hirsh J, Ginsberg JS. Use of antithrombotic agents during pregnancy.
Chest 2004; 126:627S–644S.
Antibiotic prophylaxis ?
• This is no longer recommended
– Not needed in vaginal delivery
– Routine surgical prophylaxis is adequate
• In Caesarean section
AHA/ACC consensus guidelines on the use of antimicrobial prophylaxis in cardiac disease
Changes during labour
• Contractions are problematic –
– Each injects 300 – 500 ml of volume
• Potential for circulatory overload
• Stroke volume also increases –
– Ordinarily by about 50%
• Cardiovascular demands are huge !
Post delivery care
• Haemodynamics settle with time –
– The first 72 hours most dangerous
• This is when most deaths occur
– Less need for concern later on
Siu SC, Sermer M, Colman JM, et al. Prospective multicenter study of pregnancy
outcomes in women with heart disease. Circulation 2001; 104:515–521.
The bottom line …
• Identify risk factors –
– And examine the patient
• Anticoagulants –
– Have obvious anaesthesia implications
• The post-delivery period is important –
– Don’t abandon the patient
Risk in valvular heart
disease …
Valvular lesions
• Risk can be determined in two ways –
– Maternal risk
– Foetal or neonatal risk
High maternal and foetal risk
• Severe aortic stenosis
• Mitral stenosis with symptoms
• Aortic or mitral regurgitation with symptoms
• The presence of pulmonary hypertension
• Ejection fraction of < 40%
• The presence of cyanosis
Reimold SC, Rutherford JD. Valvular heart disease in pregnancy. NEJM 2003;349:52-9
Low maternal and foetal risk
• Asymptomatic aortic valve disease
• Mitral regurgitation with normal LV function
• Mitral stenosis without pulmonary hypertension
• Mild to moderate pulmonary stenosis
• Mitral valve prolapse with no evidence of failure
Reimold SC, Rutherford JD. Valvular heart disease in pregnancy. NEJM 2003;349:52-9
High maternal risk
• Reduced ejection fraction < 40%
• Previous heart failure
• Previous stroke or TIA
Reimold SC, Rutherford JD. Valvular heart disease in pregnancy. NEJM 2003;349:52-9
High neonatal risk
• Maternal age –
– < 20 or > 35 years
• Use of anticoagulants during pregnancy
• Smoking during pregnancy
• Multiple gestations
Reimold SC, Rutherford JD. Valvular heart disease in pregnancy. NEJM 2003;349:52-9
Specifics …
Important to appreciate …
• Pregnancy tests cardiovascular reserve
• Duration of gestation is important –
– Early presentation suggests severe disease
– Late presentation indicative of reserve
Mitral stenosis
• A common lesion –
– Overall mortality of 10%
– Increases to 50% in NYHA III – IV patients
– Atrial fibrillation increases risk by 10%
• This needs to be treated aggressively
– In general pregnancy is poorly tolerated
– PAC use has been advocated with success
American College of Obstetrics and Gynecology: Invasive hemodynamic monitoring in obstetrics
and gynecology. International Journal of Gynecology and Obstetrics 1993;42:199-205
Aortic stenosis
• This is rare, but easily overlooked
– LV hypertrophy compensates
• The following are tolerated poorly –
– Tachycardia
– Vasodilatation
– Hypovolaemia
• Aggressive maintenance of BP is crucial
– This supports coronary perfusion
Pulmonary stenosis
• Patients are prone to RV failure
– Particularly post-partum
• Care must be taken with RV preload
• Avoid causes of pulmonary vasoconstriction
• Vaginal delivery has the lowest mortality
Siu SC, Sermer M, Colman JM. Prospective multicenter study of pregnancy outcomes in
women with heart disease. Circulation 2001;104:515-21
Mitral regurgitation
• This is usually tolerated well
– Unless pulmonary hypertension occurs
• Vasodilatation during pregnancy –
– Reduces complications
• At delivery pulmonary oedema is a risk
Aortic regurgitation
• Tolerated well
• Many patients’ symptoms improve
– Vasodilatation of pregnancy is beneficial
• Blood pressure should be maintained –
– Within about 15% of normal
To summarise …
• Stenotic lesions are problematic
– Duration of gestation important !
– Determine possibility for intervention
• Particularly for the mitral valve
• Regurgitant lesions are less hassle
– Take care of fluid needs carefully
– Pregnancy generally tolerated well
Unger F, Rainer WG, Horstkotte D. Standards and concepts in valve surgery. Report of the task force:
European Heart Institute (EHI) of the European Academy of Sciences and Arts and the International
Society of Cardiothoracic Surgeons (ISCTS). Indian Heart Journal 2000;52:237- 44
The main principles …
• Identify lesions and their severity early !
• Appreciate the risk to mother and foetus
• High risk lesions should be referred
– Multidisciplinary management improves outcome
• Severe stenotic lesions are problematic
• Regurgitant lesions are less of a problem
Practically ….
A few key points …
• What is the duration of pregnancy ?
– This is a good guide to reserve
– Term patients need good fluid management
• Look for signs of pulmonary hypertension –
– These are a good guide to lesion severity
• Appreciate that post-partum –
– Increased risk of pulmonary oedema
– Prolonged observation required
• Mortality is highest in the first 72 hours
What you should consider …
• Echocardiographic assessment ASAP !
– Severity of lesion
– Ejection fraction
– Potential for intervention
• Invasive haemodynamic monitoring –
– Including the use of a PAC
• Particularly in mitral stenosis
Prasad AK, Ventura HO. Valvular heart disease and pregnancy. Postgraduate Medicine
2001;110:69-88
What you should consider …
• Post-partum there is a distinct risk of –
– Pulmonary oedema
• Due to increased circulating volume
• Diuretics may be beneficial
• Take care with GPH patients –
– Particularly if they also have stenotic valves
– There is an added risk of pulmonary oedema
• Multidisciplinary management is key !
One last disease …
Peri-partum cardiomyopathy
• Aetiology uncertain
• Incidence of 1: 1 500 – 1: 4 000
• Frequent reason for ICU referral
– Patients frequently in florid failure
• Attributed to other causes !
Clinical definition …
• Heart failure –
– 1 month pre to 5 months post delivery
• Absence of previous disease
• No determinable cause
• Echo demonstration of LV failure –
–
–
–
EF < 45 %
Fractional shortening < 30 %
EDD > 2.7 cm / m2 BSA
Ray P, Murphy GJ Recognition and management of maternal cardiac disease in pregnancy.
BJA 2004; 93(3): 428-39.
Peri-partum cardiomyopathy
• Risk factors –
–
–
–
–
–
Age > 30 years
Multiparity
Pre-eclampsia
Multiple gestations
Black race
• Treatment –
– As for other forms of cardiomyopathy
Veille JC. Peripartum cardiomyopathies: a review. Am J Obstet Gynecol 1984; 148: 805–18
The last line …
• High mortality in pregnancy
• Cardiac failure most common presentation
• Pulmonary oedema is always a risk
– Post delivery a particular problem
• Echo crucial in diagnosis and management
• Identify at risk patients early !