Cadiovascular Diseases

SECTION IV: LABOR & DELIVERY Surgery Block

2012

1 Williams Obstetrics 23rd Edition

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


2012


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)


2012


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


2012


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.

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Cadiovascular Diseases