124. Cardio-Obstetrics: Pregnancy and Pulmonary Hypertension with Dr. Candice Silversides

CardioNerd (Amit Goyal), cardioobstetrics series co-chair Dr. Sonia Shah (FIT, UT Southwestern) and episode lead Dr. Kayle Shapero (FIT, UPMC) discuss pregnancy in patients with pulmonary hypertension with Dr. Candice Silversides, Associate Professor of Medicine and the Director of the Pregnancy and Heart Disease program and head of the Obstetric Medicine program at the University of Toronto. Disclosures: None Claim free CME for enjoying this episode! Abstract • Pearls • Quotables • Notes • References • Guest Profiles • Production Team CardioNerds Cardio-Obstetrics Series PageCardioNerds Episode PageCardioNerds AcademyCardionerds Healy Honor Roll CardioNerds Journal ClubSubscribe to The Heartbeat Newsletter!Check out CardioNerds SWAG!Become a CardioNerds Patron! Episode Abstract In this episode we discuss the important and challenging topic of pulmonary hypertension in pregnancy. We’ll start by discussing the prevalence of pulmonary hypertension in pregnancy, as well as the associated maternal morbidity and mortality associated with each WHO class. We will use a case to help us illustrate the appropriate workup for pulmonary hypertension patients and to help us broach the challenging topic of pregnancy termination. In this case we will further explore advanced management options including pulmonary vasodilators, anti-coagulation, and the use of mechanical support. Don’t miss this opportunity to hear Dr. Silversides’ share her wisdom on the importance of a multidisciplinary care team to plan both the delivery as well as post-partum care to help prevent adverse outcomes for both the mother and baby. Pearls Pregnancy in pulmonary hypertension, regardless of the class, is considered high risk. Even women who appear hemodynamically stable at baseline can easily decompensate in pregnancy, and thus the overall mortality and morbidity are very high.Due to the high risk of maternal morbidity and mortality during pregnancy for women with pulmonary arterial hypertension, the option of termination of pregnancy should be discussed. Multidisciplinary care teams are the key to achieving optimal pregnancy outcomes in these patients. It is critical to create a team of experts with experience in pulmonary hypertension and plan for constant communication over the course of pregnancy.Pulmonary vasodilators including CCBs, phosphodiesterase inhibitors, and prostacyclin analogues should be initiated early to mitigate adverse outcomes.The majority of the complications in pulmonary hypertension patients occur after delivery, and so having a clear and safe postpartum plan is critical to a positive outcome. Quotables “We will someday identify the women who maternal morbidity and mortality is perhaps lower and we'll be able to give a better, risk assessment. But we're not quite there yet. And so currently, any woman who has pulmonary hypertension, true pulmonary hypertension in particular, pulmonary arterial hypertension, should be advised to avoid pregnancy.“ – Dr. Silversides“Women with PH can be falsely reassuring because they can walk in and look pretty good. And they're young, you know, they're not like the normal 70-year-old you might see on the ward. And so, you think they're going to be okay, but they can spiral downward very quickly. So I do think you also have to have a very high, um, uh, level of. Uh, caution in these patients.“- Dr. Silversides on assessing PH patients in pregnancy “I would tell you that I still think honesty is the best policy. I think you should offer women as much information as we currently know, so they can make informed decisions that are right for them. I think you also do have to really be sensitive to how you're delivering this information, because remember (for) some women it will have never occurred to them that they can't have a pregnancy. They may have been planning on having a kids and family and this information can really derail them. So you do have to use sensitivity, but I think you have to do it to accommodate to the patient that you're seeing. I don't think there can be a one size fits all approach.”- Dr. Silversides on the challenging topic of how to approach pregnancy termination conversations“… continue to optimize your care, the better shape the woman is going into delivery. The better outcomes you'll have at the time of labor and delivery.”- Dr. Silversides Show notes 1. How do we define pulmonary hypertension (PH) and why is it such a big deal in pregnancy? According to recent guidelines pulmonary hypertension is a mean pulmonary artery pressure ≥ 20 mmHg.The WHO separates PH into 5 groups:Group 1: Pulmonary arterial hypertension (e.g., idiopathic, heritable [BMPR2], anorexigen associated, drug or toxin-associated, HIV, connective tissue disease associated, schistosomiasis, portal hypertension, congenital heart disease, amongst other causes)Group 2: Pulmonary hypertension due to left sided heart disease (e.g., HFrEF, HFpEF, left-side valvular heart disease)Group 3: Pulmonary hypertension due to lung disease or hypoxia: (e.g.,COPD, ILD, OSA, hypoxia without lung disease such as high altitude, developmental lung disorders)Group 4: PH due to pulmonary artery obstructions most commonly Chronic Thromboembolic Pulmonary Hypertension (CTEPH)Group 5: Multifactorial causes such as hematologic disorders (chronic hemolytic anemia, as with myeloproliferative disorders), metabolic disorders (e.g., Gaucher disease, glycogen storage diseases, CKD), and systemic disorders (e.g., pulmonary Langerhans cell histiocytosis, neurofibromatosis, sarcoidosis) The prevalence of pulmonary hypertension and pregnancy is somewhere between 0.011 and 0.02%2. Although rare, this number has been rising due to the number of congenital patients living to childbearing age, as well as the emergence of effective pulmonary vascular therapy.Complications of PH during pregnancy include:The normal physiologic changes of pregnancy (increased plasma volume, increased stroke volume, increased cardiac output, decreased systemic vascular resistance), are poorly tolerated in PH due to an inability to decrease pulmonary vascular resistance and accommodate this increased plasma volume. This can lead to increased right ventricular overload.Decrease in systemic vascular resistance and associated drop in blood pressure can also lead to decreased RV perfusion, contributing to RV failure and making it increasingly difficult to accommodate the extra afterload demand.Pregnancy is both a prothrombotic and a pro-arrhythmic state, and maternal morbidity and mortality may also be related to complications from DVT/PE/arrhythmias, all of which are poorly tolerated by a failing RV with the increased afterload of PH and possible decreased perfusion from lower SVR.Abnormal maternal hemodynamics in PH also contribute to increased fetal and neonatal complications including preterm birth, fetal and neonatal death. 2. How does the severity of PH or the patient’s WHO group impact maternal outcomes? MortalityOverall mortality for PH patients during pregnancy is quite high: Two major systematic reviews covering a time span of 30 years in nearly 200 pregnancies cited total mortality to range between 25-38%. The majority of patients died within the first month after delivery and major causes of death were heart failure, sudden cardiac death and pulmonary embolism4,5 MorbidityA comprehensive study looking at approximately 1500 pregnant women with PH from the national inpatient sample (spanning from 2003-2012) found that the rate of major adverse cardiovascular events was around 24.8%.6Karen et al assessed outcomes in ~150 pregnancies from the ROPAK study according to PH etiology (idiopathic PAH, PH due to congenital heart disease, PH due to left sided disease). Morbidity and mortality were highest in women with idiopathic PAH, and lowest in women with PH due to left sided heart disease. Complications were also higher in patient with severe PH (RVSP >70mmHg).7Meng et al assessed 49 pregnancies from four large centers and found mortality to vary according to PH subgroup: 23% mortality in Group 1 patients, as compared to a 5% mortality in all other WHO groups. Similarly, patients with severe PH (RVSP >50mmHg) had a higher need for advanced therapies as compared to women with mild PH.1Several variables determine risk during pregnancy related to PH, including the WHO group, etiology of PH, functional class, need for PAH medications at baseline, as well as cardiac size and function. 3. What is the recommended initial workup to help identify and risk stratify patients with PH? Helpful baseline information includes BNP, prior echocardiograms, as well as hemodynamics from prior right heart catheterizations.For those patients previously treated for PH, it is important to identify which medications were used in the past or are currently being prescribed. This particularly important to identify teratogenic medications like endothelin antagonists.One of the most important factors is to identify the patient’s functional status including assessing six-minute walk tests, including O2 saturation, desaturation, and distance walked.Of note, while a RHC helps define the hemodynamic profile, the entire vascular bed is more fragile during pregnancy than in a non-pregnant state, and there have been reports of pulmonary artery rupture with interventions during pregnancy.8 This must be kept in mind when assessing the need for RHC. 4. How do you approach management of patients with PH during pregnancy? Frequent follow-ups and communication with the entire multidisciplinary team are vital. This team should include cardiology, a PH specialist and/or team, high risk obstetrics, and OB anesthesia.Patients should be monitored serially throughout pregnancy with the use of BNP, echocardiography, and assessment of functional status/symptoms.While every patient situation will be different,