Rheumatic Heart Disease in Immigrant Women: The Cardiac Legacy of Untreated Strep

Rheumatic heart disease affects 40.5 million people globally and kills 306,000 annually, according to the Global Burden of Disease 2019 analysis published in the New England Journal of Medicine. In women under 40 from sub-Saharan Africa, South Asia, and Latin America, it is the most common cause of acquired heart disease. Mitral stenosis from childhood rheumatic fever remains asymptomatic for decades until pregnancy increases cardiac demand by 50 percent, converting a silent valve defect into acute pulmonary edema. Most affected women in the United States are immigrants who have never been screened.

She arrived in the United States at 24, already pregnant. The OB noted a diastolic murmur and almost mentioned it. By the third trimester, she was in pulmonary edema. Mitral stenosis. She had had rheumatic fever at age 9.

I have seen this pattern three times in the past year. Each time, the story is identical in its essential features. A young woman, born abroad, presenting with her first pregnancy. A murmur heard but not pursued. A catastrophic decompensation in the third trimester or during labor. By the time I am called, she is on a ventilator and her baby is being delivered emergently by cesarean section.

This is not a disease of the past. This is not a disease confined to distant countries. This is a disease walking into American prenatal clinics every week, wearing the face of a healthy 25-year-old, carrying a time bomb in her chest that we could have found with a $400 ultrasound.

The Molecular Memory of Childhood Infection

Rheumatic heart disease begins with a sore throat. Not just any sore throat. Group A Streptococcus, the bacterium that causes strep throat, carries a surface protein called M protein. In certain individuals with specific HLA class II alleles, this protein triggers a case of mistaken identity. Parks et al. 2021 identified a common immunologic risk locus in Black African populations that increases susceptibility to this autoimmune cross-reaction. 5 / Solid

The immune system produces antibodies against the M protein. These antibodies are imprecise. They cross-react with cardiac myosin and tropomyosin, proteins found in the heart valves. T-cells infiltrate the valve endothelium. Inflammation leads to neovascularization, then fibrosis, then commissural fusion. The valve leaflets, once supple and mobile, become thickened and immobile.

The mitral valve suffers most. In a normal heart, the mitral valve opens to an area of 4 to 6 square centimeters. After rheumatic inflammation, scar tissue narrows this opening. When the orifice area drops below 1.5 square centimeters, hemodynamics change. Blood backs up into the left atrium. Pressure transmits backward into the pulmonary veins, then the pulmonary capillaries. The patient has no idea any of this is happening. She feels fine. She exercises normally. She gets pregnant.

This is the pathophysiology of a silent catastrophe. The valve has been damaged for 15 years. The body has compensated. But compensation has limits. Pregnancy will find them.

Global Burden, American Blindspot

The numbers are staggering. Watkins et al. 2022 analyzed data from 204 countries and territories. In 2019, 40.5 million people were living with rheumatic heart disease. The highest age-standardized prevalence was in Oceania at 2.66 per 1,000, followed by South Asia at 2.14 per 1,000 and sub-Saharan Africa at 1.82 per 1,000. Among women aged 20 to 39, RHD is the leading cause of acquired heart disease in low and middle-income countries. 5 / Solid

In the United States, we rarely think about rheumatic heart disease. Widespread antibiotic treatment of strep throat eliminated it from the American consciousness decades ago. But elimination in native-born Americans does not mean elimination in American residents.

The Global Rheumatic Heart Disease Registry (REMEDY) enrolled 3,343 patients across 12 African countries, India, and Yemen. Zühlke et al. 2023 found that the median age at enrollment was 28 years. Two-thirds were women. Most had been diagnosed incidentally or during pregnancy. Only 4% had access to secondary prophylaxis with penicillin.

Among US immigrants from endemic regions, echocardiographic screening studies suggest prevalence rates of 2 to 4 percent. In a cohort of Somali refugees resettled in Minnesota, 3.2% had definite RHD on screening echocardiography. These women are in American cities right now. They are getting pregnant. Their valves are waiting to fail.

Why Pregnancy Specifically Breaks Mitral Stenosis

The hemodynamic demands of pregnancy are extreme. By 32 weeks, blood volume has increased by 40 to 50 percent. Heart rate rises by 10 to 15 beats per minute. Cardiac output increases by 30 to 50 percent. A normal heart handles this easily. A heart with mitral stenosis cannot.

Here is the mechanism. The stenotic mitral valve creates a fixed obstruction between the left atrium and left ventricle. Flow across this obstruction depends on the pressure gradient and the time available for filling. When heart rate increases, diastolic filling time shortens. The fixed orifice cannot accommodate the increased volume. Blood accumulates in the left atrium. Left atrial pressure rises. This pressure transmits backward into the pulmonary veins.

The 2018 ESC Guidelines for Management of Cardiovascular Diseases During Pregnancy classify moderate to severe mitral stenosis as WHO class III or IV cardiac risk. The pulmonary capillary wedge pressure can rise from a normal 8 to 12 mmHg to greater than 25 mmHg. Fluid transudates into the alveoli. The patient develops dyspnea, orthopnea, then frank pulmonary edema.

Labor intensifies these stresses further. Each uterine contraction autotransfuses 300 to 500 milliliters of blood into the central circulation. Pain and anxiety drive heart rate higher. The stenotic valve, which barely managed resting pregnancy physiology, fails catastrophically under delivery stress.

Saxena et al. 2019 analyzed the REMEDY pregnancy cohort and found that among women with RHD who became pregnant, 26% developed heart failure during pregnancy or postpartum. Maternal mortality was 3.4%, more than 50 times higher than the baseline maternal mortality rate in developed countries. Preterm delivery occurred in 23%. Stillbirth occurred in 4.5%. 5 / Solid

These numbers describe preventable deaths. Every one of these women could have been identified before pregnancy with a single echocardiogram.

The Clinical Framework: Rheumatic Heart Disease Screening for Endemic-Region Women

I propose a simple framework. I call it the Endemic-Region Cardiac Screening Protocol.

The first element is geographic history. At the first prenatal visit, ask every patient where she was born and where she lived before age 15. If the answer includes sub-Saharan Africa, South Asia, Southeast Asia, Latin America, the Middle East, Oceania, or the Indigenous communities of Australia and New Zealand, she is at elevated risk.

The second element is symptom history. Ask specifically about childhood illness. Did you have repeated sore throats as a child? Did you ever have joint pain with fever? Did you ever have a rash that moved or spread? Did anyone tell you that you had rheumatic fever? Many women will say no, not because they did not have rheumatic fever, but because they were never diagnosed. The infection resolved on its own. The cardiac damage was silent.

The third element is auscultation. Listen. Mitral stenosis produces a low-pitched diastolic rumble best heard at the apex with the bell of the stethoscope. The opening snap, a high-pitched sound in early diastole, precedes the rumble. This murmur is easy to miss if you are not looking for it. In pregnancy, increased blood flow may make it louder. But many clinicians hear it and document it without acting on it.

Women don’t die from what they have. Women die from what they hold.

The fourth element is the echocardiogram. For any woman from an endemic region, regardless of auscultation findings, consider preconception or early pregnancy echocardiography. The test takes 30 minutes. It costs a few hundred dollars. It can identify mitral stenosis before symptoms appear. The World Heart Federation 2023 guidelines recommend screening echocardiography for all individuals from endemic regions, particularly women of childbearing age. 5 / Solid

If mitral stenosis is present, the pregnancy can be managed. Beta-blockers slow heart rate and extend diastolic filling time. Diuretics reduce pulmonary congestion. For severe stenosis with a valve area less than 1.5 square centimeters, percutaneous balloon mitral commissurotomy can be performed during pregnancy with careful fetal shielding. Delivery planning can include continuous hemodynamic monitoring, epidural anesthesia to blunt the stress response, and avoidance of excessive fluid administration.

None of this can happen if we do not look.

The Cascade of Missed Opportunities

Return to the woman I described in the opening. She had rheumatic fever at age 9 in Addis Ababa. Her family could not afford antibiotics. The sore throat resolved after two weeks. She forgot about it. She grew up normally. She exercised. She had no limitations.

She immigrated at 22. She became pregnant at 24. At her first prenatal visit, the nurse practitioner documented a grade 2/6 murmur. The electronic health record flagged it. No one ordered an echocardiogram. At her second trimester anatomy scan, the obstetric sonographer did not evaluate the maternal heart. That is not the protocol.

By 30 weeks, she noticed she was more short of breath than her pregnant friends described. She assumed this was normal. At 34 weeks, she woke at 3 AM unable to breathe while lying flat. She sat at the edge of the bed for an hour until it passed. She did not call anyone. She assumed it would get better.

At 36 weeks, during a routine appointment, her oxygen saturation was 88% on room air. The OB heard crackles in both lung bases. She was sent to labor and delivery for evaluation. The on-call resident ordered a chest X-ray. It showed pulmonary edema. Cardiology was consulted. I walked into the room 20 minutes later.

The echocardiogram showed a mitral valve area of 0.9 square centimeters. Severe stenosis. The left atrium was massively dilated. The mean gradient across the valve was 18 mmHg, more than double the threshold for severe disease. She had been walking around for months with hemodynamics that should have been incompatible with normal activity.

We delivered her baby emergently by cesarean section under general anesthesia with invasive hemodynamic monitoring. She spent four days in the cardiac ICU. She survived. Her baby survived. But this was not success. This was luck.

Penicillin Prophylaxis: The Intervention We Fail to Provide

Once rheumatic valve damage exists, it cannot be reversed. But it can be prevented from worsening. Every subsequent Group A Streptococcal infection triggers another round of immune-mediated valve injury. The valve becomes more stenotic, more regurgitant, more calcified.

Secondary prophylaxis with penicillin prevents recurrent infections. The regimen is simple. Benzathine penicillin G, 1.2 million units intramuscularly, every 3 to 4 weeks. Alternatively, oral penicillin V 250 mg twice daily. The World Heart Federation 2023 guidelines recommend prophylaxis for 10 years after the last episode of rheumatic fever or until age 40, whichever is longer.

In the REMEDY registry, only 55% of patients with RHD were receiving secondary prophylaxis. Among those who were, adherence was erratic. Access barriers, cost, and lack of follow-up all contributed.

In the United States, we have no such excuses. Penicillin is inexpensive. It is universally available. And yet, when immigrant women with RHD present to American healthcare systems, they are rarely started on prophylaxis. The diagnosis is not made. The need is not recognized. The injection is not given.

For women of childbearing age with known RHD, monthly penicillin injections are pregnancy planning. They are cardiovascular prevention. They are maternal mortality reduction. They cost less than a single emergency department visit.

What Must Change

The failure here is systematic. It exists at multiple levels.

Primary care physicians caring for immigrant populations need education about the persistence of RHD in their patients. The assumption that rheumatic fever is a disease of the past is American exceptionalism masquerading as medical knowledge.

Obstetricians need to treat murmurs in immigrant women from endemic regions as guilty until proven innocent. A diastolic murmur is not a benign finding. It is a mandate for echocardiography. The murmur that is documented but not pursued is the murmur that kills.

Cardiologists need to integrate reproductive planning into RHD management. Every woman with mitral stenosis needs to understand what pregnancy will do to her hemodynamics. Preconception counseling must include frank discussion of risk. Some women with severe stenosis should be offered valve intervention before conception.

Health systems serving refugee and immigrant populations need screening protocols. Universal echocardiographic screening of women from endemic regions is cost-effective if it prevents even a small fraction of the emergency cardiac interventions, ICU admissions, and maternal deaths that undiagnosed RHD causes.

The Test You Should Request Before Pregnancy

If you are a woman who grew up in sub-Saharan Africa, South Asia, Southeast Asia, Latin America, the Middle East, the Pacific Islands, or Indigenous communities of Australia, you may have had rheumatic fever as a child without knowing it. The infection resolved. The valve damage persists.

Before you become pregnant, or at your first prenatal visit if you are already pregnant, take the following action.

Tell your physician: I grew up in a region where strep throat often went untreated. I need an echocardiogram to evaluate my heart valves before we proceed with this pregnancy. I specifically need to know if I have mitral stenosis.

Bring this article. Name the condition. Refuse to leave without either an echocardiogram appointment or a cardiology referral.

If mitral stenosis is found, demand a conversation about what this means for your pregnancy. Demand beta-blocker therapy if your heart rate is not well controlled. Demand monthly penicillin injections to prevent further valve damage. Demand delivery planning with a multidisciplinary cardiac obstetric team.

This is not about being difficult. This is about surviving your pregnancy.

Frequently Asked Questions

How do I know if I had rheumatic fever as a child?

Many children have rheumatic fever without a formal diagnosis. The characteristic features include sore throat followed by fever lasting more than a week, painful swelling of multiple joints that seems to move from one joint to another, skin rash consisting of pink rings on the trunk and limbs, and in severe cases, involuntary jerking movements of the face and hands. If you recall any of these symptoms during childhood, or if family members recall you being very ill with a sore throat, you may have had rheumatic fever. The only way to know if valve damage resulted is echocardiography. In endemic regions, rheumatic fever is so common that absence of a formal diagnosis means very little.

Can rheumatic heart disease be detected before pregnancy?

Absolutely. A transthoracic echocardiogram is a painless ultrasound examination of the heart that takes approximately 30 minutes. It directly visualizes the mitral valve and measures the valve opening area, the degree of thickening and calcification, and any associated regurgitation. This test should be performed before conception in any woman from an endemic region who is planning pregnancy. If abnormalities are found, there is time to intervene. If the valve is normal, you have peace of mind. There is no downside to screening and substantial upside.

Is rheumatic heart disease curable?

Valve damage from rheumatic fever cannot be reversed. The scarring, commissural fusion, and leaflet thickening are permanent structural changes. However, progression can be halted. Monthly penicillin injections prevent new streptococcal infections and thus prevent additional episodes of valve inflammation. For valves that have already become severely stenotic, percutaneous balloon commissurotomy can mechanically split the fused commissures and increase the valve opening area. In some cases, surgical valve repair or replacement is necessary. These interventions do not cure the underlying condition, but they can restore near-normal hemodynamics and allow safe pregnancy.

Why does pregnancy make rheumatic heart disease worse?

Pregnancy is a cardiovascular stress test. Blood volume increases by 40 to 50 percent to supply the growing fetus and placenta. Heart rate increases to circulate this expanded volume. Cardiac output rises by 30 to 50 percent. A normal mitral valve accommodates these changes easily. A stenotic mitral valve cannot. The fixed, narrowed opening acts as a dam. Blood backs up behind it. Pressure in the left atrium rises. This pressure transmits backward into the lungs, causing fluid to leak into the air spaces. The result is pulmonary edema, a life-threatening condition. Labor intensifies these stresses further with each contraction forcing additional blood into the central circulation.

What should I tell my OB if I grew up in a country where strep throat often went untreated?

Be direct. State: I grew up in a region where rheumatic fever is common. I may have had strep throat or rheumatic fever as a child without treatment. I need an echocardiogram to rule out valvular heart disease before we make any decisions about my pregnancy. If your OB is unfamiliar with this concern, request a referral to cardiology. If there is any resistance, print this article and bring it to your appointment. Point to the REMEDY data showing 26 percent heart failure rates and 3.4 percent maternal mortality in RHD pregnancies. Your advocacy may save your life.