• Nathan Riley, MD

Obgyno Wino Podcast Episode 20 - Pregnancy and Heart Disease (Part 2)

Updated: Jul 25, 2019

"Like passengers on a river raft we drift along, towards a precipice we have been told lies ahead, effectively distracted and seemingly unaware that the longer we wait, the harder it will be to avoid disaster.” - Ira Byock, 'The Best Care Possible: A Physician's Quest to Transform Care Through the End of Life '

The Criminal 2017 Red Blend from Truett Hurst Winery

PB#212 - Published April 2019

In Part 1, I covered:

- risk stratification of cardiovascular disease (CVD) in pregnancy

- prenatal counseling and workup

- workup of new-onset symptoms concerning for worsening or new-onset CVD in pregnancy

Five Pearls

  1. Peripartum cardiomyopathy is scary as hell and carries high mortality/morbidity rates

  2. Workup acute coronary syndrome in any pregnant or postpartum patient with chest pain or dyspnea. Atypical signs include vomiting, reflux, or diaphoresis.

  3. If symptoms persist after conservative management, benefits of angiography (restoring blood flow to ischemic myocardial tissue) likely outweigh risks.

  4. CPR is the same in a pregnant woman as a nonpregnant woman apart from left lateral displacement of the uterus if >20 wga in order to optimize resuscitative efforts. If initial attempts are unsuccessful, perimortem cesarean delivery / resuscitative hysterotomy may be warranted

  5. Hypertensive disease in pregnancy is associated with a higher risk of long-term health consequences such as heart failure, stroke, end stage renal disease, arrhythmia, and mortality.

Peripartum cardiomyopathy: the gist

- super rare (25-100/100,000 live births in the U.S.)

- presents late in pregnancy or a few months postpartum; non-ischemic

- diagnosis: ejection fraction (EF) < 45% with no previous history of cardiac disease

- cause is unclear but autoimmune, vascular, and genetic factors are being studied

- most women recover myocardial function, others will remain with chronic cardiomyopathy and heart failure

- if EF < 30% --> lesser chance of myocardial recovery, higher rate of need for left ventricular assist device implantation or cardiac transplantation

- 90% of women w/ EF > 30% can expect full myocardial recovery

- risk factors: race (esp. non-Hispanic black), age, multi-fetal pregnancies, hypertensive disorders of pregnancy, and history of peripartum cardiomyopathy in a prior pregnancy (this last one increases risk by 20%!)

Pearl: rate of death or heart transplant for women who develop peripartum cardiomyopathy is 5-10% by 1 year postpartum

Identify, assess, and manage women at high risk of peripartum cardiomyopathy like a P.R.O.

- work her up if she develops dyspnea, chest discomfort, palpitations, arrhythmias, or fluid retention

- most important diagnostic test? echo

- gets cards involved early and seek support through a multi-disciplinary care team ("Pregnant Heart Team"), which should include cardiology, MFM, and other relevant ad hoc physicians and team members

- manage as you would heart failure with reduced ejection fraction (more here)

- if diagnosed during pregnancy, timing and mode of delivery should be individualized

- you must help her weigh the risks to mom of continuing pregnancy against the risks of preterm birth

- if evidence of cardiogenic shock (hypotension, tachycardia, or end-organ compromise), her heart may be shot

- transfer to appropriate level facility as she may require a ventricular assist device or to be considered for transplant

- vaginal delivery may still be reasonable consideration as it results in less maternal morbidity and improved neonatal outcomes

Acute coronary syndrome and myocardial infarction (MI): the gist

- rare: ischemic heart disease complicates 8 per 100,000 hospitalizations for pregnancy and postpartum care

- maternal death occurs in 5-10% of affected patients, esp in peripartum period, 3-4x increase compared with nonpregnant age-matched patients

- acute coronary syndrome: broad category describing conditions in which myocardial tissue is deprived of oxygen (myocardial ischemia)

- myocardial ischemia: stable angina, unstable angina, and MI

- risk factors are similar for pregnant and nonpregnant women (age >30, non-hispanic black race, obesity, DM, smoking, hyperlipidemia, family hx of CVD, HTN in pregnancy, history of coronary artery dissection, and peripartum infection)

- causes: coronary, atherosclerosis, dissection, embolism, spasm, arteritis, occlusion, and takotsubo (stress) cardiomyopathy

- can occur during any trimester, but usually in early postpartum period

Signs of acute coronary syndrome/diagnosis

- any pregnant or postpartum patient with chest pain or cardiac symptoms should raise a flag

- atypical signs include vomiting, reflux, or diaphoresis: these may mimic normal pregnancy physiology or preeclampsia

- call your Pregnancy Heart Team early!

- during workup, place a pregnant patient in left lateral tilt to improve venous return to the heart

- ddx: pericarditis, PE, or electrolyte disturbances

- check troponins (highly sensitive and specific), get an EKG

- continuous fetal monitoring is recommended and corticosteroids may be indicated depending on gestational age

- initial management: O2, nitrates, IV heparin, beta-blockers, and aspirin

- coronary angiography remains gold standard for diagnosis (consider if ST elevation noted on EKG)

- noninvasive approach OK if patient is stable and LV function is preserved due to risks associated with angiography (e.g. iatrogenic coronary artery dissection)

- having said this, if symptoms persist after conservative management, benefits of angiography likely outweigh risks

- restoring blood flow to ischemic myocardial tissue needs to happen asap and angiography is the best way to accomplish this - if ischemia persists, it can lead to heart failure, cardiogenic shock, ventricular arrhythmias, and death

OK. So what if her heart stops?

- consider etiology: if patient just delivered, hemorrhage is most likely cause (38%), AFE is second (13%), others: anesthetics, cardiovascular disorders, drugs like mag sulfate, sepsis, metabolic, or hypertensive disorders

- 4% of pregnant or postpartum women with acute coronary syndrome experience cardiac arrest

- 4 key concepts to remember: a. increased O2 demand coupled with pharyngeal/laryngeal edema w/ greater tendency for aspiration - prioritize early bag mask ventilation and intubation b. aortocaval compression by the enlarged uterus - displace uterus to the left during chest compressions

c. prepare for fetal delivery in concert with maternal resuscitative efforts d. CPR is unchanged apart from the uterine displacement; use an AED just as you would in a nonpregnant patient; epinephrine is your vasopressor of choice

The dreaded perimortem cesarean delivery / resuscitative hysterotomy scenario

- after 4-5 minutes of resuscitative efforts, grab a scalpel (can be sooner based on your clinical impression), don't waste your time transporting the patient

- vertical incision may be faster and allow for cardiac massage or exploration of the cavity as necessary

- survival data is limited, but there are cases of injury-free infant survival rates as late as 25 minutes after maternal cardiac arrest

- delivery of the fetus can optimize CPR

Antepartum considerations for patients with CVD

- prior to delivery, fetal echo at 18-22 wks is indicated in women with congenital heart disease; this may help your NICU team immensely!

- risk of inheritance by fetus is 5-10%

- fetal growth restriction is associated with many maternal congenital and acquired cardiac lesions

- low dose aspirin prophylaxis is recommend in women at high risk for preeclampsia (vasculopathies, hypertensive disorders, etc.) - daily aspirin started between 12-28 wks; continued through delivery

- keep a close eye on blood pressures and treat as indicated (see Episode 16 or 17)

- if history of a cardiovascular event, BP target is 130 mmHg systolic and 80 mmHg diastolic (though evidence is limited)

- prompt management of severe range BPs is especially important for these patients

Intrapartum management principles for patients with CVD

- known CVD necessitates plan to birth at a hospital and the multidisciplinary plan should be well-documented in her chart

- delivery planning should begin as early as possible

- pts with stable cardiac disease can be delivery vaginally at 39-40 wga (individualized, of course, particularly if considering induction); c-section should be reserved for normal obstetric indications

- pts with severe disease may not be able to tolerate the fluctuations in cardiac output or Valsalva efforts that occur during vaginal delivery

- for these patients, sufficient regional anesthesia may assist by minimizing catecholamine release

- anticoagulation may be appropriate for many heart lesions (consult MFM and cardiology)

- LMWH at prophylactic dosing should be stopped 12 hrs before scheduled IOL or C/S (24 hrs if on therapeutic dosing)

- LMWH or warfarin can be transitioned to unfractionated heparin if anticipating delivery (can be reversed with protamine sulfate in dire straits)

- Unfractionated heparin at a twice daily dose of 7500 units or more should be stopped 12 hrs before and coags should be tested

Table 3 from PB #196

Table 4 from PB #196

- if any history of arrhythmias, cardiac monitoring may be required; risk of arrhythmias is lower with epidural use

- antibiotic prophylaxis may be required in patients at high risk for developing infective endocarditis (e.g. presence of prosthetic valves); data is all over the place - ask cardiology

Postpartum management principles

- this is the most dangerous period in your patient's pregnancy course! (up to 1 year postpartum)

- peripartum cardiomyopathy is the leading cause of postpartum death among CVD-related mortality

- cardiac monitoring is recommended in most patients, particularly if they were symptomatic or their heart disease in any way unstable prior to delivery

- in addition, pulse ox, serial lung auscultation, strict I/O, and monitoring for symptoms

- VTE prophylaxis should be strongly considered in patients with severe disease or history of prior VTE (weight-based dosing should be considered for women with BMI of 35 or greater; 0.5 mg/kg q12hr)

- recommend follow-up with cardiologist within 7-10 days of delivery for women with hypertensive disorders and within 14 days for patients with heart disease; sooner follow-up may be necessary if she develops signs or symptoms of cardiac decompensation

- reliable contraception should be discussed before delivery and ideally implemented prior to discharge; IUDs are your best bet if patient is not undergoing sterilization (mom or dad!)

- expulsion rates of IUDs placed at time of delivery are 10-25%, but potential risk may be outweighed by benefit of contraception without a gap after pregnancy

- progestin only methods are preferred over estrogen-containing contraceptives in patients with CVD due to increased VTE risk (see episode 8)

- breastfeeding should always be encouraged, "breastfeeding has favorable effects not only on hypertension through positive effects on the maternal vasculature but fosters a favorable lipid and hormonal milieu along with improved mother-infant bonding"

Long-term considerations after pregnancy

- pts with chronic HTN and those who develop hypertensive disorders of pregnancy are at risk of developing CVD after pregnancy (particularly if recurrent preeclampsia, preeclampsia that arises at < 37 wga, or IUGR)

- also a 4-fold increase in risk of heart failure

- 80% increase in risk of stroke

- 5 to 12-fold increase in risk of developing end-stage renal disease

- double the risk of atrial arrhythmias, coronary heart disease, and mortality compared with women with normotensive pregnancies

- cardiovascular assessment and follow-up is recommended within 3 months postpartum if chronic or gestational hypertensive disease, GDM, IUGR, idiopathic preterm birth, placental abruption, obesity or excessive pregnancy weight gain, sleep apnea, or age > 40 years

- risk assessment should include metabolic paneling; counseling should include smoking cessation, exercise, diet, sleep, stress management

64 views0 comments