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CHAPTER 44
Cardiovascular Disease Dr. Aida San Jose, MD, FPOGS
INTRODUCTION
INTRODUCTION TO
Cardiovascular Disease
Cardiovascular Disease in Pregnancy (GravidaCardia)
leading cause of death in women who are 25 to 44 years old Cardiac disorders complicate ~1% of pregnancies contribute significantly to maternal morbidity and mortality
rates. cardiomyopathy
⚜ cause 8% of 4200 pregnancy-related deaths in the United States from 1991 to 1999
Physiological Considerations in Pregnancy
marked pregnancy-induced hemodynamic alterations have a profound effect on underlying heart disease cardiac output
⚜ most important factor
⚜ by 50% during pregnancy
⚜ half of total increase takes place by 8 weeks AOG & is maximized by midpregnancy.
⚜ CO in EARLY Pregnancy d/t augmented stroke volume that results from
vascular resistance.
⚜ CO in LATE Pregnancy resting pulse and stroke volume even more
because of diastolic filling from pregnancy induced hypervolemia.
changes are more profound in multifetal pregnancy
cardiac output varies w/ maternal position lateral recumbent position
⚜ CO by 43% d/t PR & augmented stroke volume d/t ventricular dilatation.
⚜ Systemic and pulmonary vascular resistance were
⚜ no change in intrinsic left ventricular contractility normal left ventricular function is maintained during pregnancy
HEMODYNAMIC CHANGES in NORMAL PREGNANT WOMEN at TERM
PARAMETER CHANGE
CARDIAC OUTPUT
HEART RATE
LEFT VENTRICULAR STROKE WORK
INDEX
VASCULAR RESISTANCE
SYSTEMIC
PULMONARY
MEAN ARTERIAL PRESSURE
COLLOID OSMOTIC PRESSURE
NORMAL maternal adaptation to the "natural volume overload
state." controlling-gene expression/function of signaling
molecules that mediate reversible eccentric hypertrophy
⚜ may be activated by estrogens other G-protein-coupled receptor agonists endothelin-1 angiotensin II
Women with underlying cardiac disease may not accommodate these changes ventricular dysfunction leads to cardiogenic heart failure
w/c can occur in various weeks of gestation:
⚜ Before MIDPREGNANCY
⚜ After 28 weeks AOG Heart Failure occurs when pregnancy-induced
hypervolemia and cardiac output reach their maximum.
⚜ Peripartum Where majority of heart failures occur Occurs when a number of common obstetrical
conditions place undue burdens on cardiac function.
DIAGNOSIS
Heart Disease In Pregnancy There are certain peaks of cardiac activity during Pregnancy
It is during these periods when cardiac failure is likely to occur
Diagnosis of Heart Disease
physiological adaptations of normal pregnancy can induce symptoms and alter clinical findings that may confound the diagnosis of heart disease.
NORMAL pregnancy:
⚜ FUNCTIONAL systolic heart murmurs are common Some systolic flow murmurs may be loud Usually SOFT BLOWING systolic murmur Sometimes called as ANEMIC MURMUR
⚜ Respiratory effort is accentuated and at times suggests dyspnea
Early 3rd Trimester
During Labor
During Delivery
During Peurperium
NORMAL CARDIAC EXAMINATION in the PREGNANT WOMAN
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⚜ Edema in the lower extremities after midpregnancy is common Appears more at the end of the day & Usually
disappears after laying down NON-pitting edema
⚜ Fatigue and exercise intolerance develop in most women
Diagnostic Studies CT angiography Commonplace for suspected pulmonary embolism with
biventricular dysfunction Albumin or red cells tagged with technicium-99 rarely needed during pregnancy to evaluate ventricular
function. estimated fetal radiation exposure for a 20-mCi dose is
only about 200 mrad, well below the accepted level Regional coronary perfusion measured with thallium-201 chloride typical fetal exposure of 300 to 1100 mrad that is inversely
proportional to gestational age. Electrocardiography As the diaphragm is elevated in advancing pregnancy,
there is an average 15-degree left-axis deviation in the electrocardiogram (ECG)
mild ST changes may be seen in the inferior leads Atrial and ventricular premature contractions are relatively
frequent Pregnancy does not alter voltage findings.
Chest Radiography Use Anteroposterior and lateral chest radiographs lead apron shield is used so fetal radiation exposure is
minimal Gross cardiomegaly can usually be excluded Slight heart enlargement cannot be detected accurately
because the heart silhouette normally is larger in pregnancy.
2D Echocardiography Provides most accurate diagnosis of most heart diseases
during pregnancy. allows NONINVASIVE EVALUATION of structural and
functional cardiac factors. Some NORMAL pregnancy-induced changes include
⚜ Some tricuspid regurgitation
⚜ Some left atrial end-diastolic dimension
⚜ Some left ventricular mass
Clinical Classification of Heart Disease no clinically applicable test for accurately measuring functional
cardiac capacity. clinical classification of the New York Heart Association (NYHA) based on past and present disability uninfluenced by physical signs
NEW YORK HEART ASSOCIATION CLINICAL CLASSIFICATION
CLASS DESCRIPTION
CLASS
I UNCOMPROMISED
no limitation of physical activity
Do not have symptoms of cardiac insufficiency or
experience angina pain
CLASS
II SLIGHTLY LIMITED
Slight limitation of physical activity
Comfortable at rest
if ordinary physical activity is undertaken, discomfort
results in the form of excessive fatigue, palpitation,
dyspnea, or anginal pain
CLASS
III
MARKED
LIMITATION
Marked limitation of physical activity
Comfortable at rest
If less than ordinary activity causes excessive fatigue,
palpitation, dyspnea, or angina pain
CLASS
IV
SEVERELY
COMPROMISED
inability to perform any physical activity without
discomfort
Symptoms of cardiac insufficiency or angina may
develop even at rest, and if any physical activity is
undertaken, discomfort is increased
NYHA scoring system for predicting cardiac complications
during pregnancy. PREDICTORS OF CARDIAC COMPLICATIONS included the
following: ⚜ Prior heart failure, TIA, arrhythmia, or stroke
⚜ Baseline NYHA class III or IV or cyanosis
⚜ Left-sided obstruction defined as mitral valve area <2 cm
2
aortic valve area <1.5 cm2
peak left ventricular outflow tract gradient above 30 mm Hg by echocardiography
⚜ Ejection fraction <40%
If > 1 of these factors are present, the following risks are substantively INCREASED
⚜ pulmonary edema
⚜ sustained arrhythmia
⚜ stroke
⚜ cardiac arrest
⚜ cardiac death According to a Canadian study, the most important predictors
of complications were prior congestive heart failure depressed ejection fraction smoking
Preconceptional Counceling
Gravidocardiac women would benefit immense counseling before deciding to become pregnant
Maternal mortality rates vary directly w/ functional classification
Life-threatening cardiac abnormalities can be reversed by corrective surgery, and subsequent pregnancy is less dangerous.
In women with mechanical valves taking warfarin, fetal considerations predominate.
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Congenital Heart Disease in Offspring Many congenital heart lesions appear to be inherited as
POLYGENIC characteristics Some women with congenital lesions give birth to similarly
affected infants
MANAGEMENT
MANAGEMENT OF Gravidocardiac Patients
General Management involves a team approach with obstetrician cardiologist anesthesiologist other specialists as needed
Plan is formulated to MINIMIZE cardiovascular changes likely to be poorly tolerated by an individual woman.
4 changes that affect management (American College of Obstetricians and Gynecologists, 1992) 50% in blood volume & cardiac output in EARLY 3
rd
TRIMESTER Further fluctuations in volume & cardiac output in
PERIPARTUM PERIOD in systemic vascular resistance, reaching a nadir in the
SECOND TRIMESTER, & then to 20% below normal by LATE PREGNANCY
Hypercoagulability, which is of special importance in women requiring anticoagulation before pregnancy with coumarin derivatives
Both prognosis and management are influenced by the nature and severity of the specific lesion in addition to the functional classification
Management of NYHA Class I & II Disease GENERAL INFO NYHA class I and most in class II proceed through
pregnancy without morbidity. Special attention on prevention and early recognition of
heart failure.
⚜ Onset of congestive heart failure is generally GRADUAL.
⚜ 1ST
WARNING SIGN of CHF Persistent basilar rales frequently accompanied
by a nocturnal cough SERIOUS Heart Failure
⚜ SYMPTOMS sudden in ability to carry out usual duties dyspnea on exertion Attacks of smothering with cough
⚜ Clinical findings Hemoptysis Progressive edema Tachycardia.
Infection with sepsis syndrome
⚜ an important factor in precipitating cardiac failure. Bacterial Endocarditis
⚜ a deadly complication of valvular heart disease Each woman should receive instructions to
⚜ Avoid contact with persons who have respiratory infections, including the common cold
⚜ To report at once any evidence for infection. Pneumococcal & Influenza Vaccines
⚜ recommended. PROHIBITED during pregnancy
⚜ Cigarette smoking Has adverse cardiac effects and propensity to
cause upper respiratory infections.
⚜ Illicit drug use may be particularly harmful Cocaine or Amphetamines have adverse cardiovascular effects
Intravenous drug use the risk of Infective Endocarditis.
LABOR AND DELIVERY vaginal delivery
⚜ PREFERRED unless there are obstetrical indications for cesarean delivery.
Any form of manipulations should be minimized to prevent
infection
⚜ Hence, limit internal exams when possible
Induction is generally safe Pulmonary Artery Catheterization
⚜ may be indicated for hemodynamic monitoring
⚜ invasive monitoring is rarely indicated. Considerations during labor in a mother with SIGNIFICANT
HEART DISEASE
⚜ Mother should be kept in a semirecumbent position with lateral tilt
⚜ Vital signs are taken frequently between contractions.
⚜ Signs that suggest impending ventricular failure. Increases in pulse rate > 100 bpm Respiratory rate >24 per minute Associated dyspnea
If there is any evidence of cardiac decompensation, intensive medical management must be instituted immediately.
Delivery itself does not necessarily improve the maternal condition.
Emergency operative delivery
⚜ May be particularly hazardous.
⚜ Both maternal and fetal status must be considered in the decision to hasten delivery.
ANALGESIA & ANESTHESIA Relief from pain and apprehension is important. Anxiety
⚜ should be lessened at all times during labor &
delivery
Pain
⚜ intravenous analgesics provide satisfactory pain relief for some women
⚜ Continuous Epidural Analgesia recommended in most cases. Very good for pain free labor
Major problem of conduction/regional analgesia maternal hypotension
☀ especially dangerous in women with intracardiac shunts in whom flow may be reversed.
❧ Blood passes from right to left within the heart or aorta and thereby bypasses the lungs.
☀ Hypotension can also be life-threatening with pulmonary hypertension or aortic stenosis because ventricular output is dependent on adequate preload.
⚜ Narcotic Conduction Analgesia or General Anesthesia preferable ALTERNATIVE to continuous epidural
if mother is hypotensive or have intracardiac shunts
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vaginal delivery
⚜ in mild cardiovascular compromise Epidural Analgesia w/ Intravenous Sedation
often suffices. Minimizes Intrapartum Cardiac Output
Fluctuations Allows forceps or vacuum-assisted delivery
⚜ Subarachnoid blockade NOT generally recommended in women with
significant heart disease. Cesarean Delivery
⚜ Epidural Analgesia PREFERRED by most clinicians with caveats for its
use with pulmonary hypertension
⚜ General Endotracheal Anesthesia w/ thiopental, succinylcholine, nitrous oxide, &
at least 30-percent oxygen also proved satisfactory
INTRAPARTUM HEART FAILURE Cardiovascular decompensation during labor
⚜ may manifest as either or both of the following: pulmonary edema with hypoxia hypotension
Proper therapeutic approach depends on the specific hemodynamic status & the underlying cardiac lesion such as:
⚜ Decompensated mitral stenosis with pulmonary edema due to fluid overload Best approached with aggressive diuresis
⚜ Tachycardia Heart rate control with β-blocking agents is
PREFERRED.
⚜ Decompensation & HYPOTENSION d/t aortic stenosis β-blocking agents could prove FATAL.
Hence, empirical therapy may be hazardous, unless the cause & pathophysiology are clear
PUERPERIUM Women who have shown little or no evidence of cardiac
distress during pregnancy, labor, or delivery may still decompensate postpartum.
⚜ Hence, it is important that meticulous care be continued into the puerperium
Postpartum complications
⚜ are more serious in a mother w/ heart disease: Postpartum hemorrhage Anemia Infection Thromboembolism
⚜ often act in concert to precipitate postpartum heart failure
pulmonary edema
⚜ caused by or worsened by permeability edema resulting from endothelial activation capillary-alveolar leakage
STERILIZATION AND CONTRACEPTION tubal sterilization
⚜ if to be performed after vaginal delivery, it is best to delay the procedure until mother is hemodynamically near normal afebrile
not anemic ambulates normally w/o evidence of distress
⚜ In NON-Gravidocardiac & Stable patients, tubal ligation can be done 1 hour after delivery Semilunar infra-umbilical incision is done, access
tubes & ligate Contraception
⚜ Advised if tubal ligation is not done after delivery
⚜ Physician should give detailed contraceptive advice
⚜ Estrogen-Progestin Oral Contraceptives Are RELATIVELY CONTRAINDICATED in women
w/ hypertension, prosthetic valves & other valvular heart disease d/t its possible thrombogenic action
⚜ OCPs containing low-dose estrogen and low-androgenic progestins NOT a/w an risk of myocardial infarction Safer for women w/ hypertension & prosthetic
valves
⚜ There is no contraindication to oral contraceptives in non-smoking women older than 35 years of age
⚜ Smoking and oral contraceptives act synergistically to this risk, especially
beyond 35 years of age
⚜ Sterilization should be considered because of serious problems during pregnancy
Management of Class III & IV Disease EPIDEMIOLOGY uncommon today
⚜ 3% of ~600 pregnancies were complicated by NYHA class III heart disease
⚜ NO women had class IV If women in this class decide to be pregnant, they must
understand the risks and cooperate fully with planned care. If feasible, women with some types of severe cardiac
disease should consider PREGNANCY INTERRUPTION. If the pregnancy is continued, PROLONGED
HOSPITALIZATION or BED REST is often necessary. Epidural analgesia for labor and delivery usually recommended.
Vaginal delivery is preferred in most cases labor induction can usually be done safely less stressfule
Cesarean delivery usually limited to obstetrical indications
⚜ dystocia
⚜ abruption placenta considerations
⚜ specific cardiac lesion
⚜ overall maternal condition
⚜ availability of experienced anesthesia personnel
⚜ availability of general support facilities These women often tolerate major surgical
procedures poorly and are best delivered in a unit facility with management of complicated cardiac disease
These women require continuous heart montoring d/t they can easily go through heart failure
Antimicrobial Prophylaxis
To be given 30-60 minutes prior to delivery RECOMMENDED DRUG Ampicillin 2 gms IV or Amoxicillin 2 gms oral
ALTERNATIVES If penicillin sensitive
⚜ Cefazolin or Ceftriaxone 1 gm IV If w/ history of anaphylaxis
⚜ Clindamycin 600 mg IV If w/ enterococcal infection
⚜ + Vancomycin
⚜
MO
DE
of
DEL
IVER
Y VAGINAL DELIVERY Recommended
RELIEF FROM PAIN
Epidural Anesthesia: PREFERRED
General Anesthesia:
If w/ HYPOTENSION
Subarachnoid anesthesia:
AVOIDED
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SURGICALLY CORRECTED
Heart
Cardiac Lesions That Usually Doesn’t Get Diagnosed
Till Adulthood atrial septal defects pulmonic stenosis bicuspid aortic valve aortic coarctation
Valve Replacement Before Pregnancy A number of reproductive-aged women have had a prosthesis
implanted to replace a severely damaged mitral or aortic valve Successful pregnancies have followed prosthetic replacement
of even three heart valves EFFECTS ON PREGNANCY Pregnancy is undertaken only after serious consideration. Women with a mechanical valve prosthesis must be
anticoagulated
⚜ If not pregnant, warfarin is recommended a number of serious complications can develop, especially
with mechanical valves
⚜ Thromboembolism involving the prosthesis
⚜ hemorrhage from anticoagulation
⚜ deterioration in cardiac function Overall, the maternal mortality rate is 3 to 4 percent with
mechanical valves fetal loss is common
Porcine tissue valves are much safer during pregnancy
⚜ primarily because anticoagulation is not required as thrombosis is rare
COMMON complications that develop in 5-25% of pregnancies:
⚜ valvular dysfunction
⚜ deterioration
⚜ failure DISADVANTAGE
⚜ bioprostheses are not as durable as mechanical ones
⚜ valve replacement averages every 10 to 15 years ANTICOAGULANT MANAGEMENT The critical issue for women with mechanical prosthetic
valves is anticoagulation
⚜ heparin may be less effective than warfarin in preventing thromboembolic events.
Warfarin
⚜ ADVANTAGE most effective to prevent mechanical valve
thrombosis
⚜ DISADVANTAGE teratogenic FETAL EFFECTS Miscarriage Stillbirths Fetal malformation
Low-Dose Heparin
⚜ Prophylaxis using low-dose unfractionated heparin definitely inadequate if used alone by itself, may NOT prevent the following
complications w/ prosthetic valves during pregnancy massive thrombosis of a mitral prosthesis maternal death
Recommendations for Anticoagulation
⚜ Table 44-6
Anticoagulation of Pregnant Women w/ Cardiac Disorders (per Dr. San Jose)
⚜ Usually given for patients w/ MECHANICAL prosthetic valves
⚜ Unfractionated Heparin Given at 6-12 weeks AOG Again at 36 weeks AOG Discontinued before delivery to prevent
excessive bleeding during delivery If delivery supervenes while the
anticoagulant is still effective
☀ extensive bleeding is encountered
❧ protamine sulfate
☘ given IV
☘ prevent excessive bleeding
⚜ Warfarin Started at 13 weeks AOG Discontinued at 36 weeks AOG Resumed postpartum
⚜ TARGET international normalized ratio (INR) 2.0 to 3.0.
Anticoagulant therapy with warfarin or heparin AFTER delivery
⚜ AFTER vaginal delivery may be restarted after 6 hours
⚜ AFTER cesarean delivery full anticoagulation is withheld, but the duration
is not exactly known. wait at least 24 hours, preferably 48 hours,
following a major surgical procedure. BREAST FEEDING
⚜ warfarin derivatives are safe for breast-feeding women because of minimal transfer to milk.
CONTRACEPTION estrogen-progestin oral contraceptives
⚜ relatively contraindicated in women with prosthetic valves because of their possible thrombogenic action
Sterilization
⚜ should be considered because of the serious pregnancy risks faced by women with significant heart disease
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MAJOR CARDIAC VALVE DISORDERS
TYPE CAUSE PATHOPHYSIOLOGY PREGANCY TREATMENT
MITRAL
STENOSIS Rheumatic Valculitis
LA Dilation & passive
pulmonary
Hypertension
Heart failure from fluid overload
⚜ Activity is w/ (+) pulmonary congestion
⚜ Dietary sodium is restricted
⚜ Start diuretic therapy
A-Fib Tachycardia
⚜ Beta blockers
⚜ Epidural anesthesia for labor
⚜ Avoid fluid overload
⚜ Vaginal delivery preferred
MITRAL
INSUFFICIENCY
Rheumatic Valculitis LV dilation &
eccentric
hypertrophy
Ventricular function improves w/
afterload ⚜ Intrapartum prophylaxis of bacterial endocarditis Mitral Valve Prolapse
LV Dilatation
AORTIC
STENOSIS
Congenital
LV concentric
hypertrophy & CO
Moderate stenosis tolerated
⚜ Close observation if asymptomatic
⚜ Symptomatic women includes strict limitation of activity & prompt
treatment of infections
Bicuspid Valve
Severe stenosis is life threatening w/
preload like obstetrical hemorrhage or
regional analgesia
⚜ If symptoms persist despite bed rest, valve replacement or valvotomy
⚜ Forceps or vacuum delivery for standard obstetrical indications in
hemodynamically stable woman
⚜ Intrapartum prophylaxis of bacterial endocarditis
AORTIC
INSUFFICIENCY
Rheumatic Valculitis
LV hypertrophy &
dilatation
Ventricular function improves w/
afterload
⚜ Symptoms necessitates therapy for heart failure, including bed rest,
sodium restriction & diuretics
Congenital ⚜ Epidural analgesia is used for labor & delivery
Connective Tissue
Disease ⚜ Bacterial endocarditis prophylaxis at delivery
PULMONARY
STENOSIS
Congenital Severe stenosis a/w
RA & RV
enlargement
Mild stenosis well tolerated
⚜ Surgical correction before or during pregnancy if condition worsen Rheumatic Valculitis
Severe stenosis a/w right heart failure &
atrial arrhythmias
Valve Replacement During Pregnancy Valve replacement usually postponed until after delivery when possible may be lifesaving during pregnancy
major maternal and fetal morbidity and mortality maternal mortality rates with cardiopulmonary bypass are
between 1.5 and 5 percent. fetal mortality rate approaches 20 percent.
To minimize these bad outcomes surgery is done electively when possible if surgery is done
⚜ pump flow rate is maintained >2.5 L/min/m2
⚜ normothermic perfusion pressure is >70 mm Hg
⚜ pulsatile flow is used
⚜ hematocrit is >28 percent. MITRAL VALVOTOMY DURING PREGNANCY Tight mitral stenosis that requires intervention during
pregnancy was previously treated by closed mitral valvotomy
percutaneous transcatheter balloon dilatation of the mitral valve
⚜ has largely replaced surgical valvotomy during pregnancy
⚜ >90% successful
Pregnancy After Heart Transplantation transplanted heart responds normally to pregnancy-induced
changes. complications common during pregnancy
⚜ ½ developed hypertension
⚜ 22% suffered at least one rejection episode during pregnancy
⚜ Delivered usually by cesarean
⚜ 3/4th
of infants were liveborn Post-partum
⚜ Maternal death
VALVULAR HEART
Diseases
Rheumatic Fever uncommon in the United States because of less crowded living conditions
availability of penicillin evolution of nonrheumatogenic streptococcal strains
Still, it remains the chief cause of serious mitral valvular disease
Mitral Stenosis Rheumatic endocarditis causes 3/4
th of mitral stenosis
Mitral Valve normal mitral valve surface area is 4.0 cm
2.
MITRAL STENOSIS symptoms usually develop when stenosis is < 2.5 cm
2
contracted valve impedes blood flow from the left atrium to the ventricle.
SYMPTOMS
⚜ Dyspnea most prominent complaint causes pulmonary venous hypertension edema.
⚜ Fatigue
⚜ Palpitations
⚜ Cough
⚜ Hemoptysis With tight stenosis left atrium is dilated left atrial
pressure is chronically elevated significant passive pulmonary hypertension
The preload of normal pregnancy, as well as other factors that cardiac output, may cause ventricular failure with pulmonary edema in these women who have a relatively fixed cardiac output.
1/4th
of women with mitral stenosis have cardiac failure for the first time during pregnancy
Because the murmur may not be heard in some women, this clinical picture may be confused with idiopathic peripartum cardiomyopathy
With significant stenosis
⚜ tachycardia shortens ventricular diastolic filling time and increases the mitral gradient left atrial, pulmonary venous & capillary pressures pulmonary edema.
⚜ sinus tachycardia often treated prophylactically with β-blocking
agents. Atrial tachyarrhythmias, including fibrillation
⚜ are common in mitral stenosis and are treated aggressively.
⚜ Atrial fibrillation also predisposes to
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mural thrombus formation cerebrovascular embolization that can
cause stroke Pregnancy Outcomes Complications are directly a/w degree of valvular stenosis.
⚜ Mitral-valve area <2 cm2 have greatest risk for
complications such as Heart failure Arrhythmias Fetal-growth restriction More common in mitral valve area < 1.0
cm2.
Maternal prognosis
⚜ Related to functional capacity
⚜ More maternal deaths in women in nyha classes iii or iv.
Management Limited physical activity is generally recommended. If symptoms of pulmonary congestion develop
⚜ Activity is further reduced
⚜ Dietary sodium is restricted
⚜ Diuretic therapy is started
⚜ β-blocker drug is usually given to blunt the cardiac response to activity and anxiety
If new-onset atrial fibrillation develops
⚜ intravenous verapamil 5 to 10 mg
⚜ electrocardioversion For chronic fibrillation
⚜ DRUGS to slow ventricular response
⚜ Digoxin
⚜ β-blocker
⚜ calcium-channel blocker If persistent fibrillation
⚜ Therapeutic anticoagulation with heparin With severe stenosis and chronic heart failure,
⚜ insertion of a pulmonary artery catheter may help guide management decisions.
Antimicrobial Prophylaxis for bacterial endocarditis Labor and delivery particularly stressful for women with symptomatic mitral
stenosis. Pain, exertion, and anxiety cause tachycardia, with
possible rate-related heart failure. Epidural analgesia for labor
⚜ Is ideal, but with strict attention to avoid fluid overload.
⚜ Abrupt increases in preload may increase pulmonary capillary wedge pressure and cause pulmonary edema.
Wedge pressures increase even more immediately postpartum.
⚜ Likely due to loss of the low-resistance placental circulation along with the venous "autotransfusion" from the lower extremities, pelvis, and the now-empty uterus
Vaginal delivery
⚜ Preferable
⚜ Elective induction Is reasonable so that labor and delivery Attended by a scheduled, experienced team.
Mitral Insufficiency
d/t is improper coaptation of mitral valve leaflets during systole causing some degree of mitral regurgitation
SEQUELAE left ventricular dilatation eccentric hypertrophy
Chronic mitral regurgitation COMMON CAUSES
⚜ rheumatic fever
⚜ mitral valve prolapse
⚜ left ventricular dilatation of any etiology dilated cardiomyopathy
Less common causes
⚜ calcified mitral annulus
⚜ some appetite suppressants
⚜ older women
⚜ ischemic heart disease Libman-Sacks endocarditis AKA: Verrucous, Marantic, Or Nonbacterial Thrombotic
Endocarditis Nonbacterial endocarditis w/ Mitral valve vegetations relatively common in women with antiphospholipid
antibodies sometimes coexist with systemic lupus erythematosus can lead to Acute mitral insufficiency
⚜ d/t rupture of a chorda tendineae, infarction of papillary muscle, or leaflet perforation from endocarditis.
NONPREGNANT patients symptoms from mitral valve incompetence are rare valve replacement is seldom indicated unless infective
endocarditis develops During PREGNANCY mitral regurgitation
⚜ is well tolerated d/t systemic vascular resistance results in less regurgitation.
Heart failure
⚜ rarely develops during pregnancy occasionally tachyarrhythmias need to be treated. Intrapartum prophylaxis against bacterial endocarditis may
be indicated
Aortic Stenosis
a disease of aging & women younger than 30 years, it is most likely due to a congenital lesion.
By itself, is less common since the decline in incidences of rheumatic diseases
most common lesion is a bicuspid valve Stenosis reduces the normal 2- to 3-cm
2 aortic orifice and
creates resistance to ejection. Reduction in the valve area to a fourth its normal size produces
severe obstruction to flow and a progressive pressure overload on the left ventricle
SEQUELAE Concentric left ventricular hypertrophy end-diastolic
pressures ejection fraction cardiac output Characteristic clinical manifestations develop late chest pain syncope heart failure sudden death from arrhythmias.
Life expectancy averages only 5 years after exertional chest pain develops
⚜ Hence, Valve replacement is indicated for symptomatic patients.
PRINCIPAL UNDERLYING HEMODYNAMIC PROBLEM fixed cardiac output a/w severe stenosis
During PREGNANCY Clinically significant aortic stenosis is uncommonly
encountered.
⚜ mild to moderate degrees of stenosis are well tolerated,
⚜ severe disease is life threatening. FACTORS that preload further and aggravate the fixed
cardiac output
⚜ Examples regional analgesia vena caval occlusion hemorrhage.
⚜ these factors cardiac, cerebral, and uterine perfusion. Women with valve gradients >100 mmHg appear
to be at greatest risk. MANAGEMENT ASYMPTOMATIC woman with aortic stenosis
⚜ no treatment
⚜ close observation is required SYMPTOMATIC woman
⚜ INITIAL approach
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strict limitation of activity prompt treatment of infections
⚜ If symptoms persist despite bed rest valve replacement or valvotomy using
cardiopulmonary bypass must be considered balloon valvotomy for aortic valve disease
☀ avoided because of serious complications
❧ stroke
❧ aortic rupture
❧ aortic valve insufficiency
❧ death
☀ In rare cases, it may be lifesaving to perform valve replacement during pregnancy
⚜ For women with critical aortic stenosis intensive monitoring during labor is important. Pulmonary artery catheterization may be helpful because of the narrow
margin separating fluid overload from hypovolemia.
Women with aortic stenosis are dependent on adequate end-diastolic ventricular filling pressures to maintain cardiac output and systemic perfusion. Abrupt decreases in end-diastolic volume may result in
☀ Hypotension
☀ Syncope
☀ myocardial infarction
☀ sudden death KEY to management avoidance of ventricular preload maintenance of cardiac output
During labor and delivery women should be managed on the "wet"
side, maintaining a margin of safety in intravascular volume in anticipation of possible hemorrhage.
☀ In women with a competent mitral valve, pulmonary edema is rare, even with moderate volume overload.
narcotic epidural analgesia
☀ ideal
☀ avoids potentially hazardous hypotension encountered in standard conduction anesthesia
❧ can cause immediate and profound effects of decreased filling pressures in severe aortic stenosis
Forceps or vacuum delivery
☀ used for standard obstetrical indications in hemodynamically stable women.
⚜ LATE Postpartum Complication pulmonary edema arrhythmias cardiac interventions death
Aortic Insufficiency
Aortic regurgitation is the diastolic flow of blood from the aorta into the left ventricle.
CAUSES of aortic valvular incompetence are rheumatic fever connective-tissue abnormalities
⚜ Marfan syndrome aortic root may dilate, resulting in regurgitation
congenital lesions bacterial endocarditis aortic dissection. appetite suppressants
⚜ fenfluramine
⚜ dexfenfluramine ergot-derived dopamine agonists
SEQUELAE left ventricular hypertrophy and dilatation
⚜ MANIFESTATIONS slow-onset fatigue dyspnea edema
⚜ rapid deterioration usually follows. During PREGNANCY Aortic insufficiency is generally well tolerated
⚜ Like mitral valve incompetence, diminished vascular resistance is thought to improve the lesion.
If w/ symptoms of heart failure
⚜ Give diuretics
⚜ Bed rest Epidural analgesia
⚜ used for labor and delivery bacterial endocarditis prophylaxis
Pulmonic Stenosis Pulmonary artery valve is affected by rheumatic fever far less
often than the other valves. usually congenital may be a/w: Fallot tetralogy Noonan syndrome
Clinical diagnosis Auscultation of Systolic ejection murmur over the
pulmonary area that is louder during inspiration. Severe Stenosis SEQUELAE d/t hemodynamic burdens of pregnancy can precipitate
⚜ right-sided heart failure
⚜ atrial arrhythmias surgical correction recommended before or during pregnancy if symptoms
progress. During PREGANCY Cardiac complications were infrequent MATERNAL Noncardiac Effects
⚜ hypertension
⚜ thromboembolism FETAL EFFECTS
⚜ preterm delivery
⚜ anencephaly
⚜ having heart defects pulmonary stenosis complete transposition
OTHER
Cardiovascular Conditions
Mitral Valve Prolapse diagnosis implies the presence of a pathological connective
tissue disorder: Myxomatous Degeneration May involve the following structures causing Mitral
insufficiency
⚜ valve leaflets themselves
⚜ annulus
⚜ chordae tendineae Most women are asymptomatic and are diagnosed by routine
examination or while undergoing echocardiography. Some women with symptoms have Anxiety Palpitations atypical chest pain syncope
Those with redundant or thickened mitral valve leaflets are at increased risk for sudden death infective endocarditis cerebral embolism
EFFECTS ON PREGNANCY Pregnant women rarely have cardiac complications
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⚜ pregnancy-induced hypervolemia may improve alignment of the mitral valve
⚜ Women without evidence of pathological myxomatous change may in general expect excellent pregnancy outcome
For women who are symptomatic
⚜ β-blocking drugs sympathetic tone relieve chest pain and palpitations reduce the risk of life-threatening arrhythmias
Mitral valve prolapse with regurgitation or valvular damage is considered to be a moderate risk for bacterial endocarditis
Peripartum Cardiomyopathy AKA: Idiopathic Cardiomyopathy of Pregnancy After exclusion of an underlying cause for heart failure, the
default diagnosis is either Idiopathic Cardiomyopathy Peripartum Cardiomyopathy
⚜ similar to idiopathic dilated cardiomyopathy encountered in nonpregnant adults
National Heart, Lung, and Blood Institute and the Office of Rare Diseases DIAGNOSTIC CRITERIA: Development of cardiac failure in the last month of
pregnancy or within 5 months after delivery Absence of an identifiable cause for the cardiac failure Absence of recognizable heart disease prior to the last
month of pregnancy Left ventricular systolic dysfunction demonstrated by
classic echocardiographic criteria
⚜ depressed shortening fraction or ejection fraction. disease is acute, rather than a preexisting one preceding
pregnancy Findings AFTER endomyocardial biopsies & tests in
NONPREGNANT patients who had UNEXPLAINED cardiomyopathy 50% had myocarditis 50% had viral genomic material for
⚜ VIRUSES found parvovirus B19 human herpesvirus 6 Epstein-Barr virus human cytomegalovirus
⚜ reactivation of latent viral infection triggered an autoimmune response.
POSSIBLE UNDERLYING CONDITIONS causing Cardiomyopathy Chronic Hypertension w/ Superimposed Preeclampsia
⚜ MOST COMMON cause of HEART FAILURE during PREGNANCY
⚜ In some cases, mild antecedent hypertension is undiagnosed, and when superimposed preeclampsia develops, it may cause otherwise inexplicable peripartum heart failure.
⚜ obesity a common cofactor with chronic hypertension can cause or contribute to underlying ventricular
hypertrophy. obesity alone was a/w a doubling of the risk of
heart failure in nonpregnant individuals Dilated cardiomyopathy
⚜ also found in human immunodeficiency virus (HIV) infection
OBSTETRICAL COMPLICATIONS of peripartum heart failure that either contribute to or precipitate heart failure. Preeclampsia
⚜ common and may precipitate afterload failure Acute anemia from blood loss
⚜ magnifies the physiological effects of compromised ventricular function
Infection and accompanying fever
⚜ increase cardiac output and oxygen utilization. INCIDENCE highly dependent upon the diligence of the search for a
cause. varies from 1 in 1500 to 1 in 15,000 pregnancies.
Women with cardiomyopathy (+) signs and symptoms of congestive heart failure.
⚜ Dyspnea Universal
⚜ Other symptoms Orthopnea Cough Palpitations Chest pain
HALLMARK FINDING
⚜ impressive cardiomegaly Echocardiographic findings
⚜ ejection fraction <45%
⚜ fractional shortening <30%
⚜ end-diastolic dimension >2.7 cm/m2
MANAGEMENT treatment for heart failure
⚜ Limited Sodium intake & Diuretics preload
⚜ hydralazine or other vasodilators afterload
⚜ angiotensin-converting enzyme inhibitors & Angiotensin-Receptor Blockers CONTRAINDICATED during PREGNANCY d/t
marked fetal effects May be given POSTPARTUM
⚜ Digoxin given for its INOTROPIC EFFECTS unless complex
arrhythmias are identified.
⚜ Prophylactic heparin to manage high incidence of associated
thromboembolism
⚜ Extracorporeal membranous oxygenation Lifesaving in a woman with fulminating
cardiomyopathy. Acute mortality rate Varies, depending again on the accuracy of the diagnosis. Immediate mortality rate was approximately 2 percent.
Long-T prognosis The distinction between peripartum heart failure from an
identifiable cause versus idiopathic cardiomyopathy is of primary importance.
Women with peripartum cardiomyopathy who regain ventricular function within 6 months have a good prognosis
Those who do not, however, have high morbidity and mortality rates such as
⚜ End-stage heart failure
⚜ Pulmonary embolism
⚜ Cerebral ischemic stroke
⚜ Heart transplantation
⚜ Death
Hypertrophic Cardiomyopathy Concentric left ventricular hypertrophy may be Familial Sporadic form not related to hypertension
⚜ AKA: Idiopathic Hypertrophic Subaortic Stenosis.
SURVIVAL according to underlying cause of cardiomyopathy
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Epidemiology Common 1 in 500 adults
CHARACTERISTICS cardiac hypertrophy myocyte disarray interstitial fibrosis
ETIOLOGY mutations in any one of more than a dozen genes that
encode proteins of the cardiac sarcomere. Inheritance is autosomal dominant
The abnormality is in the myocardial muscle, and it is characterized by left ventricular myocardial hypertrophy with a pressure gradient to left ventricular outflow
DIAGNOSIS ECHOCARDIOGRAM
⚜ (+) hypertrophied and nondilated left ventricle in the absence of other cardiovascular conditions.
Most women are asymptomatic SIGNS & SYMPTOMS Dyspnea anginal or atypical chest pain syncope arrhythmias sudden death
⚜ most common form of death
⚜ Asymptomatic patients with runs of ventricular tachycardia are especially prone to sudden death.
EXACERBATING FACTORS Symptoms are usually worsened by exercise
PREGNANCY congestive heart failure is common may have adverse cardiac symptoms
⚜ dyspnea
⚜ chest pain
⚜ palpitations. MANAGEMENT
⚜ similar to that for aortic stenosis
⚜ Strenuous exercise is prohibited during pregnancy
⚜ Abrupt positional changes are avoided to prevent reflex vasodilation and decreased preload.
⚜ Likewise, drugs that evoke diuresis or diminish vascular resistance are generally not used.
⚜ If symptoms develop Angina Give β-adrenergic or calcium-channel
blocking drugs
⚜ Spinal analgesia Contraindicated
⚜ epidural analgesia controversial
⚜ Endocarditis prophylaxis given if bacteremia is suspected
OUTCOMES
⚜ Infants rarely demonstrate inherited lesions at birth
Infective Endocarditis
PATHOLOGY involves cardiac endothelium produces vegetations that usually deposit on a valve. can involve a native or a prosthetic valve may be a/w
⚜ intravenous drug abuse HIGH RISK GROUPS h/o corrective surgery for congenital heart disease
⚜ ~ 50% of affected adults have a known preexisting heart lesion
ETIOLOGY SUBACUTE BACTERIAL ENDOCARDITIS
⚜ usually d/t a low-virulence bacterial infection superimposed on an underlying structural lesion. usually native valve infections
⚜ Organisms that cause indolent endocarditis Viridans-group streptococci Enterococcus species
ACUTE ENDOCARDITIS
⚜ TOP 3 organisms Viridans-group streptococci Coagulase-positive staphylococcus aureus MC in intravenous drug abusers
Enterococcus species Prosthetic Valve Infective Endocarditis
⚜ ORGANISMS Staphylococcus epidermidis
Acute, Fulminating Endocarditis
⚜ ORGANISMS Streptococcus pneumoniae Neisseria gonorrhoeae
Antepartum Endocarditis
⚜ ORGANISMS Neisseria sicca Neisseria mucosa Causes maternal death
Escherichia coli following cesarean delivery in an otherwise
healthy young woman. DIAGNOSIS SYMPTOMS: variable & often develop insidiously.
⚜ Fever virtually universal
⚜ Murmur heard in 80 to 85 percent of cases
⚜ Anorexia
⚜ Fatigue
⚜ Other constitutional symptoms Common frequently described as "flulike."
SIGNS
⚜ Anemia
⚜ Proteinuria
⚜ Manifestations of embolic lesions Petechiae Focal neurological manifestations Chest or abdominal pain Ischemia in an extremity Heart failure
Symptoms may persist for several weeks before the diagnosis is found, and a high index of suspicion is necessary.
Duke criteria
⚜ (+) Blood cultures for typical organisms
⚜ Evidence of endocardial involvement Echocardiography
⚜ Useful
⚜ DISADVANTAGE lesions < 2 mm in diameter or those on the
tricuspid valve may be missed.
⚜ A negative echocardiographic study does not exclude endocarditis.
MANAGEMENT Treatment is primarily medical with appropriate timing of
surgical intervention if necessary. Knowledge of the infecting organism is imperative for
sensible antimicrobial selection.
⚜ For MOST viridans streptococci DRUG of choice penicillin G IV + gentamicin for 2 weeks Complicated infections are treated longer
women allergic to penicillin IV ceftriaxone or vancomycin for 4 weeks.
⚜ Staphylococci, enterococci, and other organisms treated according to microbial sensitivity for 4 to
6 weeks Prosthetic valve infections treated for 6 to 8 weeks
⚜ Persistent native valve infection may require replacement more commonly indicated with an infected
prosthetic valve
⚜ Right-sided infections caused by methicillin-resistant S. aureus (MRSA)
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DRUG of Choice vancomycin
Other drugs Daptomycin
☀ a cyclic lipopeptide. ENDOCARDITIS IN PREGNANCY uncommon during pregnancy and the puerperium INCIDENCE
⚜ 1 in 16,000 deliveries TREATMENT
⚜ Same as nonpregnant women PROGNOSIS
⚜ maternal mortality rate of 25 to 35 percent. ANTIMICROBIAL PROPHYLAXIS antimicrobial prophylaxis to prevent bacterial endocarditis
is questionable. American Heart Association recommends prophylaxis
based on risk stratification
OBSTETRICAL PROCEDURES
⚜ Prophylaxis for bacterial endocarditis administered intrapartum to women at risk only
in the presence of suspected bacteremia or active infection incidence of transient bacteremia at
delivery
☀ 1 to 5 percent OPTIONAL for women undergoing an
uncomplicated delivery who are at high risk for endocarditis
given preferably 30 to 60 minutes before the procedure.
⚜ DRUG options DRUG of Choice IV
☀ Ampicillin, 2 g
☀ cefazolin or ceftriaxone, 1 g ORAL
☀ Ampicillin, 2 g For penicillin-sensitive patients cefazolin or ceftriaxone, 1 g
if there is a history of anaphylaxis clindamycin, 600 mg IV
If w/ enterococcus infection vancomycin
⚜ RECOMMENDED Prophylaxis Regimen Prophylaxis should be COMPLETED within 30
minutes before the procedure is begun INITIAL DOSE Give Ampicillin IV or IM (2g) + gentamicin
IV 1.5 mg/kg (maximum of 120 mg ) 6 HOURS LATER Give 1 g parenteral Ampicillin or oral
amoxicillin If allergic to penicillin (Ampicillin)
Give Vancomycin, 1 g intravenously over 1 to 2 hours
In women who are at moderate risk for endocarditis gentamicin & 2nd dose of Ampicillin may be
eliminated
ISCHEMIC HEART
Disease
Ischemic Heart Disease Mortality from coronary artery disease and myocardial
infarction is a rare complication of pregnancy. INCIDENCE OVERALL Incidence
⚜ declining d/t reductions in major risk factors and better medical therapies
Incidence in PREGNANCY
⚜ increasing
⚜ mortality rate from coronary heart disease among all pregnant women aged 35 to 44 years has been increasing by an average of 1.3 percent per year
Pregnant women with coronary artery disease commonly have classic risk factors such as Diabetes Smoking Hypertension Hyperlipidemia Obesity
Diagnosis during pregnancy not different from the nonpregnant patient. Measurement of serum levels of the cardiac-specific
contractile protein: TROPONIN I
⚜ accurate for diagnosis of IHD
⚜ normally undetectable across normal pregnancy. levels do not increase following either vaginal or
cesarean delivery
⚜ higher in preeclamptic women than in normotensive controls.
PREGNANCY WITH PRIOR ISCHEMIC HEART DISEASE advisability of pregnancy after a myocardial infarction is
unclear.
⚜ Ischemic heart disease is characteristically progressive, and because it is usually associated with hypertension or diabetes, pregnancy in most of these women seems inadvisable.
Complications during pregnancy
⚜ congestive heart failure
⚜ worsening angina
⚜ death Pregnancy increases cardiac workload
⚜ ventricular performance should be assessed prior to conception using ventriculography radionuclide studies echocardiography coronary angiography
⚜ If there is no significant ventricular dysfunction, pregnancy will likely be tolerated.
MYOCARDIAL INFARCTION DURING PREGNANCY mortality rate in pregnancy is increased compared with
age-matched nonpregnant women
⚜ overall maternal mortality rate of 30-35 percent
⚜ mortality rate 40 percent in the third trimester Women who sustain an infarction < 2 weeks prior to labor
are at especially high risk of death TREATMENT similar to that for nonpregnant patients CONSERVATIVE Management
⚜ ACUTE management administration of nitroglycerin and morphine close blood pressure monitoring
⚜ Lidocaine
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used to suppress malignant arrhythmias
⚜ Calcium-channel blockers or beta blockers given if indicated
⚜ Tissue plasminogen activator for pregnant women remote from delivery
Surgical procedures when indicated d/t acute or unrelenting disease
⚜ Percutaneous transluminal coronary angioplasty
⚜ Stent placement during pregnancy If the infarct has healed sufficiently
⚜ cesarean delivery reserved for obstetrical indications
⚜ epidural analgesia ideal for vaginal labor
⚜ Epidural analgesia or general anesthesia may be used for cesarean delivery
⚜ pulmonary artery catheter monitoring INDICATIONS if an infarction occurs within 6 months of
delivery if there is ventricular dysfunction.