Authors: Lindsay A. Gallagher, Shuo Li, Zeynep Alpay Savasan, Thomas Schwann, Saavia S. Girgla
Categories: Valvular Heart Disease, acute heart failure, aortic valve, cardiovascular disease, computed tomography, pregnancy, valve replacement
Source: JACC Case Reports
Authors: Lindsay A. Gallagher, Shuo Li, Zeynep Alpay Savasan, Thomas Schwann, Saavia S. Girgla
Pregnant women with underlying cardiovascular disease are at an increased risk of maternal-fetal morbidity and mortality especially in the setting of symptomatic stenotic valvular heart disease.
A 35-year-old female at 17 weeks gestation presented to the emergency department with exertional dyspnea for 3 months and was diagnosed with decompensated heart failure. Echocardiogram demonstrated left ventricular ejection fraction of 45% with severe aortic valve stenosis and moderate aortic regurgitation. A multidisciplinary pregnancy heart team recommended urgent surgical aortic valve replacement prior to fetal maturity.
Hemodynamic changes in pregnancy, such as increased blood volume and heart rate, may unmask asymptomatic cardiovascular disease. Specifically, increased blood volume during pregnancy is poorly tolerated in patients with stenotic valvular disease and may result in NYHA functional class III or IV heart failure.
Cardiovascular comorbidities in pregnant women require careful evaluation by a multidisciplinary pregnancy heart team to determine optimal timing and approach for intervention.
A 35-year-old G3P1011 female at 17 weeks of gestation presented to the hospital with worsening exertional dyspnea and chest tightness ongoing for 3 months. A murmur was noted at her first prenatal visit, but her symptoms were attributed to asthma at that time. Her pregnancy was otherwise uncomplicated. On presentation, she was in mild distress (heart rate 127 beats/min, blood pressure 148/104 mm Hg, respiratory rate 18 breaths/min, oxygen saturation 93% on room air). She denied vaginal bleeding, discharge, or cramping. Exam revealed a grade 3/6 harsh late-peaking systolic murmur with diminished second heart sound, clear lungs, and no peripheral edema.
The patient had a history of a murmur and hyperlipidemia diagnosed in childhood. She began lipid-lowering treatment at age 18 but suspended treatment after 5 years due to inconsistent primary care follow-up. An echocardiogram at age 20 was unremarkable. Her first pregnancy was 5 years prior and was complicated with gestational hypertension requiring labetalol use during third trimester with a term induction of labor at 39 weeks and an uncomplicated vaginal delivery. There was no cardiac murmur noted during her first pregnancy. Of note, her father had hyperlipidemia and early-onset coronary artery disease with a myocardial infarction in his mid-40s.
The initial differential included aortic stenosis (AS), hypertrophic obstructive cardiomyopathy, and mitral regurgitation. A benign flow murmur due to hemodynamic changes from pregnancy was felt to be less likely given the quality of the murmur and her symptomatic presentation.
Initial testing revealed an elevated high-sensitivity Troponin I (0.09 ng/mL) and B-type natriuretic peptide (230 pg/mL). Prepregnancy labs demonstrated a significantly elevated lipoprotein(a) (286 mg/dL) and low-density lipoprotein (364 mg/dL). Initial electrocardiography showed sinus tachycardia with a new left bundle branch block (Figure 1).Figure 1Electrocardiogram on Admission Revealed Sinus Tachycardia and a (New) Left Bundle Branch Block With a QRS Interval of 142 ms
Echocardiography revealed an ejection fraction of 45%, mild concentric left ventricular hypertrophy, and a severely calcified aortic valve (AV) with reduced leaflet excursion (Figure 2). The AV mean gradient was 75 mm Hg with a peak velocity of 5.3 m/s and calculated AV area of 0.5 cm^2^. Color flow doppler demonstrated moderate aortic regurgitation and moderate mitral regurgitation; the right ventricular systolic pressure was 25 to 30 mm Hg.Figure 22-Dimensional Echocardiography on Hospital Day 2 Revealed an EF of 45% and Severe AV Stenosis (Likely Trileaflet) With a Mean Gradient of 75 mm HgThe peak velocity across the AV was 5.3 m/s, and the peak and mean valve gradients were 113 mm Hg and 75 mm Hg, respectively. AV = aortic valve; EF = ejection fraction.
Invasive coronary angiography demonstrated a 50% stenosis of the left main coronary artery and 60% stenosis of the proximal left anterior descending artery (Figure 3).Figure 3Invasive Coronary AngiogramInvasive coronary angiogram demonstrated (A) right coronary artery spasm without evidence of atherosclerosis and (B) left main 50% stenosis and left anterior descending 60% stenosis.
Fetal ultrasounds were performed routinely and revealed an anatomically normal fetus with appropriate fetal growth and antenatal testing.
The case was discussed in a multidisciplinary setting that included cardiologists, cardiothoracic surgeons, imaging specialists, anesthesiologists, and obstetricians. This pregnancy heart team determined that the patient was not a candidate for balloon aortic valvuloplasty (BAV) as her pre-existing aortic regurgitation could abruptly worsen after balloon expansion.
The patient's NYHA functional class III heart failure symptoms worsened, and her clinical condition was anticipated to deteriorate further as she approached peak pregnancy-related volume expansion between 28 and 32 weeks. After multiple meetings with the pregnancy heart team, the consensus was to proceed with intervention prior to delivery. Due to her contraindication to BAV, the team initially explored transcatheter aortic valve replacement (TAVR).
To assess her candidacy for TAVR, the patient underwent a cardiac computed tomography angiogram (Figure 4) which showed severe calcification of the AV (calcium score 1,941 Agatston units), a narrow aortic root measuring 23 mm, and left main coronary artery arising 8 mm above the aortic annulus. The pregnancy heart team concluded that TAVR was unsafe due to a narrow aortic root with small aortic sinuses, heavy AV calcification, and low-lying coronary anatomy. Because these anatomic findings increase the risk of coronary occlusion or sinus rupture during TAVR, a shared decision was made to proceed with surgical AV replacement (SAVR) via open sternotomy during the second trimester.Figure 4Preoperative 3D-Gated Cardiac CT Angiogram (TAVR CT Protocol)A series of images from the preoperative 3D gated cardiac CT angiogram. (A) Chest, abdomen, and pelvis CT angiography of vascular anatomy. (B): (Top) AV calcium score 1,941 Agatston units, (Bottom) expanded view of aortic root anatomy, (C) 4-chamber CT view demonstrating concentric left ventricular hypertrophy. AV = aortic valve; CT = computed tomography; TAVR = transcatheter aortic valve replacement.
The patient was transferred to the cardiac intensive care unit for continued monitoring prior to surgery. Two days before the scheduled surgery, she developed acute shortness of breath followed by a witnessed syncopal event. Telemetry demonstrated brief asystole followed by junctional rhythm (heart rate 20 beats/min). The patient underwent 2 to 3 minutes of cardiopulmonary resuscitation and did not require intubation. Her heart rate improved with prompt resuscitation and atropine. Urgent obstetric assessment demonstrated reassuring fetal heart tones.
At 20 weeks, the patient underwent urgent SAVR employing a 19-mm St Jude Medical Regent mechanical prosthesis and aortic root endarterectomy due to aortic root calcifications. In addition, she underwent 2 vessel coronary artery bypass grafting of her left anterior descending and ramus arteries given her severe left main disease. Total aortic cross-clamp time was 115 minutes, cardiopulmonary bypass was 138 minutes, and the patient required 3 U of packed red blood cells and 2 units of platelets.
The patient was extubated on postoperative day 1. Warfarin was initiated on postoperative day 3, and she was discharged home on postoperative day 6 on warfarin (international normalized ratio goal 2-3), aspirin 81 mg daily, and low-dose labetalol. She was followed up closely after discharge and reported a significant improvement in symptoms and energy through term. A primary Cesarean section was planned to lower risk of aortic and cardiac strain during labor and vaginal delivery. She transitioned to low-molecular-weight heparin (LMWH) 3 days prior to the C-section. Bilateral tubal ligation was also performed at that time as she did not desire future pregnancy. She delivered a healthy baby boy at 37 weeks of gestation, and statin therapy was initiated after delivery.
Patients with undiagnosed or previously asymptomatic cardiovascular disease may present during pregnancy due to physiologic changes in hemodynamics such as increases in stroke volume, heart rate, and cardiac output.^1^ In addition, blood volume also expands, with a smaller increase in erythrocyte mass, resulting in dilutional anemia.^2^ While these changes are typically well tolerated in pregnancy, patients with certain underlying structural heart disease, especially stenotic lesions, may be unable to tolerate this hemodynamic flux and can decompensate rapidly. This case exemplifies a unique clinical challenge regarding the necessity of an urgent valvular intervention during pregnancy, along with timing and approach, to ensure optimal maternal-fetal outcomes.
The 2020 American College of Cardiology/American Heart Association guidelines for management of patients with valvular heart disease recommend that women with severe valve disease (Stages C and D) be monitored in a tertiary-care center with a dedicated team of specialists including cardiologists, surgeons, anesthesiologists, and maternal-fetal-medicine obstetricians with expertise in the management of pregnant patients with high-risk cardiac complications.^3^ These guidelines also indicate that valve intervention is reasonable in pregnant patients with severe AS if there is evidence of hemodynamic deterioration or NYHA functional class III or IV heart failure symptoms.^3^
Options for valve intervention include SAVR, BAV, and TAVR. SAVR is associated with high rates of maternal mortality (7.3%), fetal prematurity (50%), and fetal loss (15%-25%) but may be necessary for some patients as demonstrated in our case.^1^^,^^4^ Although there is limited research on BAV and TAVR outcomes during pregnancy, these minimally invasive options are generally preferred during pregnancy due to the high risks associated with SAVR.4, 5, 6
Valve intervention for severe AS is dependent on valve morphology and expertise of the treatment team.^3^ For SAVR, careful consideration must be given to the choice between a mechanical and a bioprosthetic valve.^5^ Society guidelines indicate that bioprosthetic valves are preferred over mechanical valves in women of childbearing age because of the risks of valve thrombosis and anticoagulation during pregnancy for both mother and fetus.^3^ These risks however must be weighed against the reduced durability of bioprosthetic valves in young women. In our case, the patient's young age and small aortic root influenced the decision to opt for mechanical valve replacement.^7^
Timing of surgery during pregnancy is another important factor and dependent on maternal clinical status, gestational age, and shared decision-making between the patient and the pregnancy heart team. Current expert consensus indicates that second trimester is the optimal period for operative management since development of the fetus is largely complete.^2^ Higher maternal and fetal complication rates have also been reported for procedures performed in third trimester.^2^
In addition, the decision about anticoagulation after mechanical valve replacement during pregnancy is complex. There is no single optimal anticoagulation strategy; inherent trade-offs exist between the two main options—warfarin and LMWH. Warfarin is most effective at preventing thrombosis and is the preferred agent in mechanical valves. However, warfarin may increase the rate of fetal loss and other teratogenic effects due to placental transfer.^8^ LMWH is not teratogenic but is less effective at preventing thrombosis.^3^ The decision should be shared between the patient and the pregnancy heart team.
Management of critical AS in pregnancy is complex. Current guidelines are helpful but remain somewhat limited. Many decisions including the type and timing of intervention as well as selection of anticoagulation depend on each patient's specific clinical situation, cardiac anatomy, and personal preferences. It is critical to employ the use of a multidisciplinary pregnancy heart team to assess clinical factors and provide patient-specific recommendations on management. Collaboration among multiple specialties and team members ensures optimal outcomes for the patient and fetus.Visual SummaryTimeline of EventsAV = aortic valve; BNP = B-type natriuretic peptide; CPR = cardiopulmonary resuscitation; ECG = electrocardiography; Echo = echocardiography; INR = international normalized ratio; PEA = pulseless electrical activity.
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.Take-Home Messages•Stenotic heart disease in pregnancy is complex, and all pregnant patients with severe valvular stenosis should undergo close monitoring throughout pregnancy.•Multidisciplinary collaboration in the form of a dedicated pregnancy heart team is critically important to ensuring positive outcomes in pregnant patients with cardiovascular disease.Equipment ListUsed for Patient CareImaging•Transesophageal echocardiography (TEE) (Philips Healthcare)○Epic TEE probe•Cardiac CT (Siemens Flash, Siemens Healthineers)○ECG-gated cardiac CT angiography (multiphase) for assessment of aortic annulus size, AV, and aortic root measurementsAccess for heart catheterization•Micropuncture needle and wire•0.35-inch J-wire and 6-inch sheath•JR 4 and JL 3.5 diagnostic coronary catheters•Pigtail catheter for AS gradient assessmentSurgery•AV replacement; SJM (St. Jude Medical) Regent 19-mm mechanical prosthesisThis list contains the equipment used to perform the various imaging and interventional procedures.