Emergency Bentall procedure at 15 weeks’ gestation for giant aortic root aneurysm in Marfan syndrome: a case report

Abstract

Background

Pregnancy in women with Marfan syndrome markedly increases the risk of life-threatening aortic complications due to superimposed haemodynamic and hormonal stress on an intrinsically fragile aortic wall. Management becomes particularly challenging when a giant aortic root or ascending aortic aneurysm with severe aortic regurgitation is diagnosed during early pregnancy before fetal viability.

Case summary

A 19-year-old primigravid woman at 15 weeks and 2 days of gestation with known Marfan syndrome presented with persistent palpitations. Evaluation revealed a giant fusiform aneurysm involving the aortic root and ascending aorta measuring 69 mm on transthoracic echocardiography and ∼9–10 cm intraoperatively, severe aortic regurgitation due to annular dilation, and left ventricular systolic dysfunction with an ejection fraction of 40%–42%. Following multidisciplinary consultation and counselling regarding maternal and fetal risks, urgent surgical intervention was undertaken without termination of pregnancy. The patient underwent an emergency Bentall procedure. The perioperative course was complicated by major bleeding requiring delayed sternal closure and transfusion support. Post-operative echocardiography demonstrated a functioning mechanical prosthesis with acceptable haemodynamics and persistent severe left ventricular systolic dysfunction with an ejection fraction of 25%–30%. Obstetric ultrasonography confirmed a viable fetus. The patient was discharged in stable condition on post-operative day 11.

Discussion

This case demonstrates that emergency aortic root replacement during early second-trimester pregnancy may be lifesaving in selected patients with Marfan syndrome and severe aortic pathology when guided by multidisciplinary coordination and meticulous perioperative management.

Learning points.

• In pregnant patients with Marfan syndrome, giant aortic aneurysm with severe aortic regurgitation may require urgent surgery even before fetal viability.

• Emergency Bentall surgery during pregnancy requires individualized multidisciplinary decision-making, including counselling on maternal and fetal risks.

• During cardiopulmonary bypass in pregnancy, maintenance of normothermia, adequate perfusion pressure, and optimized flow is important to support uteroplacental perfusion.

Introduction

Marfan syndrome is an inherited connective tissue disorder characterized by progressive aortic root and ascending aortic dilation and a high lifetime risk of acute aortic syndromes.¹ Pregnancy further increases this risk because of elevated cardiac output, increased blood volume, and hormonal effects on the aortic wall.² Guidelines therefore recommend lower diameter thresholds for prophylactic aortic surgery in women with Marfan syndrome planning pregnancy.^3,4

Life-threatening aortic disease during pregnancy requires multidisciplinary evaluation.² Although cardiopulmonary bypass carries significant fetal risk, especially in early gestation,⁵ maternal survival remains the priority.⁶ We report emergency Bentall surgery at 15 weeks of gestation in a patient with Marfan syndrome, giant aortic root and ascending aortic aneurysm, severe aortic regurgitation, and left ventricular dysfunction.

Summary figure

Created in BioRender. Mottahedi, M. (2026) https://BioRender.com/hlislkr

Case presentation

A 19-year-old primigravid woman at 15 weeks and 2 days of gestation was referred with a 1-year history of persistent palpitations. Her history included Marfan syndrome, known ascending aortic aneurysm, and hypothyroidism. Pre-pregnancy aortic measurements and formal counselling were not documented.

On presentation, she was tachycardic with a palpable precordial thrill. Electrocardiography showed sinus tachycardia with inferior ST-segment depression. Renal function and electrolytes were normal. Obstetric ultrasonography confirmed a live intrauterine fetus with normal cardiac activity and amniotic fluid volume.

Transthoracic echocardiography showed a giant fusiform aneurysm of the aortic root and tubular ascending aorta, measuring 69 mm at the sinuses of Valsalva (Figure 1). The trileaflet aortic valve had severe annular dilation and leaflet malcoaptation, causing severe aortic regurgitation consistent with annuloaortic ectasia. The left ventricle was markedly dilated with global hypokinesia and moderately reduced systolic function (ejection fraction, 40%–42%). Right ventricular size and function were preserved, with no pericardial effusion. The proximal aortic arch measured 25 mm, the proximal abdominal aorta was normal, and no descending thoracic aortic dilation was seen on available transthoracic echocardiographic views. Computed tomography was deferred because of early gestation. Transoesophageal echocardiography was not performed, and surgical planning relied primarily on transthoracic echocardiography. Intraoperative inspection later showed greater ascending aortic dilation, measuring ∼9–10 cm and extending to about 3 cm proximal to the aortic arch.

Figure 1.

Preoperative transthoracic echocardiography. Parasternal long-axis view demonstrating severe dilation of the aortic root and ascending aorta, with a maximal diameter of ∼6.9 cm.

An emergency multidisciplinary conference was convened with cardiac surgery, cardiology, obstetrics and gynaecology, and maternal-fetal medicine. Given the extreme aneurysmal size, severe aortic regurgitation, and impaired ventricular function, she was considered at high risk of acute aortic complications. After counselling on maternal and fetal risks, including pregnancy termination, she declined termination and chose urgent surgery while continuing the pregnancy.

The patient underwent emergency open-heart surgery. Intraoperative inspection confirmed extensive aortic root and ascending aortic aneurysmal dilation, measuring ∼9–10 cm (Figure 2A). After cardiopulmonary bypass and aortic cross-clamping, the aneurysmal segment was resected, and a size 23 mechanical composite valved conduit was implanted using the Bentall technique with coronary button reimplantation (Figure 2B). Cardiopulmonary bypass and cross-clamp times were 166 and 132 min, respectively. Normothermia and controlled perfusion pressures were maintained to preserve uteroplacental blood flow.

Figure 2.

Intraoperative findings during emergency Bentall procedure. (A) Intraoperative view demonstrating extreme aneurysmal dilation of the aortic root and ascending aorta extending to the proximal arch, with marked thinning of the aortic wall. (B) Post-reconstruction appearance following implantation of a composite mechanical valved conduit using the Bentall technique with coronary button reimplantation after complete excision of the aneurysmal segment.

The procedure was complicated by diffuse anastomotic bleeding consistent with perioperative coagulopathy, requiring delayed sternal closure and transfer to cardiac intensive care with temporary chest closure for planned re-exploration.

The patient received substantial blood product transfusion and underwent planned re-exploration on post-operative day 1, with confirmed haemostasis and definitive sternal closure. Post-operative fever prompted infectious disease consultation and antibiotic adjustment. Anticoagulation for the mechanical prosthesis was initiated with unfractionated heparin, then transitioned to warfarin after maternal-fetal medicine consultation confirmed no obstetric contraindication at this gestational age.

Follow-up transthoracic echocardiography demonstrated severe left ventricular systolic dysfunction (ejection fraction, 25%–30%) with spontaneous echo contrast, consistent with a low-flow state. The mechanical aortic prosthesis functioned appropriately, with expected transvalvular gradients and no paravalvular regurgitation. Post-operative obstetric ultrasonography confirmed an ongoing viable pregnancy with preserved fetal cardiac activity and normal amniotic fluid volume (Figure 3). After stabilization, the patient was transferred to the cardiac surgery ward and discharged in stable condition on post-operative day 11. After discharge, the pregnancy continued and the child was later reported alive and well. Cardiac follow-up extended to September 2024, with no documented aortic reoperation, prosthetic valve complication, or recurrent aortic event.

Figure 3.

Post-operative obstetric ultrasonography. Doppler tracing demonstrating a normal fetal heart rate of 159 beats per minute following maternal cardiac surgery.

Discussion

This case represents an extreme pregnancy-associated aortopathy in Marfan syndrome, with massive aortic root and ascending aortic dilation, severe aortic regurgitation, and left ventricular dysfunction in the early second trimester. The 9–10 cm aneurysm, severe valve incompetence, and impaired systolic function placed the patient at very high risk of rupture or dissection.

Cardiac surgery with cardiopulmonary bypass during pregnancy carries significant fetal risk, especially in early gestation. However, when life-threatening aortic disease is present, maternal survival remains the priority.^5,6 Prior reports have linked early-pregnancy cardiopulmonary bypass with increased fetal loss, underscoring the difficulty of decision-making in such cases.⁶ In this case, extreme aneurysmal dilation, severe aortic regurgitation, and ventricular dysfunction necessitated urgent surgery after multidisciplinary consultation and informed patient preference. This favourable outcome should not be considered predictable, as maternal or fetal complications may still occur despite timely intervention and optimal care.^5,6

Cardiopulmonary bypass during pregnancy requires careful intraoperative management to reduce fetal risk. In this case, normothermia and adequate perfusion pressures were maintained to support uteroplacental blood flow, consistent with recommended strategies during cardiopulmonary bypass in pregnancy.⁶ These measures may have helped preserve fetal viability despite the prolonged bypass duration.

The early post-operative decline in left ventricular systolic function was likely multifactorial. Severe chronic aortic regurgitation had caused marked ventricular dilation and preoperative systolic dysfunction, with adverse remodelling and impaired contractile reserve potentially contributing to persistent early dysfunction after valve correction.⁷ Perioperative myocardial stunning, prolonged cardiopulmonary bypass and cross-clamp times, and major bleeding with coagulopathy may also have contributed. Left ventricular systolic function later improved on follow-up echocardiography.

A mechanical composite valved conduit was chosen because of the patient’s young age, urgent life-threatening presentation, and need to avoid early structural valve deterioration requiring repeat high-risk surgery. Although a bioprosthetic valve could simplify anticoagulation during pregnancy, long-term durability was prioritized.

ESC guidelines recommend pre-pregnancy counselling, risk stratification, and Pregnancy Heart Team management for women with Marfan syndrome and other heritable thoracic aortic diseases.⁴ They also support lower thresholds for prophylactic aortic root surgery in women planning pregnancy because of increased gestational aortic risk.⁴ The absence of documented pre-pregnancy aortic measurements limited assessment of aneurysm progression from baseline. Massive aneurysmal enlargement in early pregnancy underscores the importance of pre-pregnancy counselling, close surveillance, and timely referral in high-risk patients.⁴

This case is notable for multiple high-risk features, including pre-viable second-trimester presentation, Marfan syndrome, giant aortic root and ascending aortic aneurysm, severe aortic regurgitation, and preoperative left ventricular systolic dysfunction. It highlights the complexity of individualized multidisciplinary decision-making when maternal risk is extreme and pregnancy continuation is desired. In selected life-threatening cases, emergency Bentall surgery during early pregnancy may be feasible; however, favourable maternal and fetal outcomes should not be considered predictable despite timely intervention and optimized care.

Lead author biography

Dr. Mehran Mottahedi is a Medical Doctor and MSc candidate in Surgical and Interventional Sciences at McGill University. His research focuses on cardiovascular disease, with particular emphasis on plasma proteomics and biomarker discovery for dilated cardiomyopathy. Using advanced proteomic approaches, his work aims to improve early diagnosis, prognostic stratification, and understanding of disease mechanisms in cardiomyopathy. He has co-authored several peer-reviewed publications and presented his research at national and international scientific conferences. His interests include translational cardiovascular research, cardiac surgery, and the integration of molecular science with clinically driven cardiovascular investigation.

Author contributions

Mehran Mottahedi (Data curation, Investigation, Writing—original draft [lead], Writing—review & editing [supporting]), Setareh Garousi (Data curation, Investigation, Writing—review & editing [supporting]), Mahdi Kahrom (Writing—review & editing [supporting]), and Behrooz Mottahedi (Conceptualization, Investigation, Resources, Supervision, Writing—review & editing [lead])

Funding

The authors received no specific financial support for the research, authorship, or publication of this article.

Data availability

The data underlying this article cannot be shared publicly due to patient confidentiality. Relevant data are included in the article, and additional de-identified clinical information may be available from the corresponding author upon reasonable request, subject to institutional policies.