Peripartum Cardiomyopathy

The symptoms and clinical features seen in PPCM patients are similar to those seen in any other form of cardiomyopathy. Initially, the condition could be asymptomatic. Later on, symptoms of heart failure start to develop including fatigue, cough, orthopnea, shortness of breath, dyspnea, edema, pulmonary congestion, chest pain, syncope, and decreased cardiac output. Some patients present with sudden cardiac death as the first presentation. Because many of these symptoms are observed in normal pregnant women, PPCM or other cardiac diseases during pregnancy are not easy to diagnose.

Physical examination of patients with PPCM will reveal the signs of heart failure, which include peripheral edema, ascites, tachycardia, elevated jugular venous pressure, cardiomegaly, mitral stenosis, tricuspid stenosis, pulmonary crackles, third heart sound, arrhythmias, and liver enlargement.

PPCM is considered a rare condition, and is a diagnosis of exclusion. Good history and physical examination are required to exclude all other causes of heart failure. If PPCM is suspected based on heart failure signs and symptoms, such as dyspnea, cough, chest pain, and new murmurs, then further workup and investigations are required to reach the diagnosis quickly. Further workup includes echocardiography, which is very important not only in the diagnosis of PPCM, but also in monitoring and follow up of the management and treatment.

Criteria for diagnosing PPCM:

1. No other cause of heart failure was detected.
2. The previous medical history does not include any heart diseases before the last month of pregnancy.
3. The heart failure started during the last month of pregnancy or within the first five months after delivery.
4. Left ventricular systolic dysfunction occurring in the peripartum period revealed by echocardiography.

In addition to echocardiography, magnetic resonance tomography of the heart can be used as a complementary tool to help in the diagnosis and evaluation of PPCM patients. Laboratory studies do not help in the diagnosis of the condition.

PPCM is managed by a multiple disciplinary team, with main goals to decrease signs and symptoms, improve the hemodynamic status, and improve the long term outcomes.

The main components in the management of PPCM include diuretics, sodium restiriction, vasodilators, digoxin, and beta-blockers. Heparin anticoagulation should be initiated if a thrombus was detected by echocardiography. Warfarin should not be used for anticoagulation during pregnancy, and it can be used after the delivery of the baby. Caution should be taken when making changes in drugs during breast feeding, as special attention should be given to the fetus and the fetal safety. Dopamine antagonists that inhibit prolactin secretion, such as bromocriptin, can be used to prevent the deterioration in the left ventricular size as well as the systolic function. However, researchers suggest that bromocriptine should be used with caution.

Supported ventilation may be needed in women with respiratory failure due to pulmonary edema. Blood pressure and cardiac monitoring are required. In some cases, medical treatment is not successful, and a ventricular assist device may be used for mechanical cardiovascular support. If medical management was not successful and the patient is not improving, then cardiac transplantation should be considered as an option.

The prognosis of PPCM depends mainly on the severity of the condition and the time when the patient developed it. If the condition was developed during pregnancy, the survival rates are better and the heart size usually returns to normal after delivery. However, in other women the prognosis can be worse and it could lead to death in up to 50% of patients.

The etiology of PPCM is still unknown until this moment. However, many etiologic causes and components have been suggested and are currently being studied by researchers [8].

Viral infections

According to different studies on patients with PPCM, DNA of different viruses (cytomegalocirus, parcovirus B19, Epstein-Barr virus, or human herpes virus 6) was detected in endomyocardial biopsy specimens. It was also noticed that the ejection fraction of the left ventricle was affected depending on whether the viral infection was cleared or not. Other studied showed that when pregnant and non-pregnant mice are injected with viruses (echivirus and coxackievirus), pregnant mice developed a worse myocarditis.

These studies suggest that these viral infections could be the cause behind a pathologic immune response targeting the cardiac proteins and causing damage to the heart. Based on different studies, the prevalence of myocarditis in patients with PPCM is between 8.8% to 78% [9] [10]. Right ventricular endomyocardial biopsy studies revealed myocarditis in PPCM patients [11] [12].

Inflammation and apoptosis

Different studies and experiments on mice suggested that apoptosis of cardiac myocytes plays a role in the etiology of PPCM. Elevations in different inflammatory mediators, such as interleukin 6 and tumor necrosis factor alpha, were noticed as the classification of the functional heart failure deteriorated.

Abnormal hemodynamic response

Different body changes occur during pregnancy, including elevations in cardiac output and blood volume, which in turn lead to hypertrophy of the left ventricle. However, this hypertrophy is transient and reversible, and once the cardiac output decreases, the left ventricle returns to normal.

Chimerism

During pregnancy, sometimes cells migrate from the fetus to the mother and reside there. This phenomenon is called chimerism (cells could also migrate from the mother to the fetus in this phenomenon) and could lead to the formation of autoantibodies and the initiation of an immune response targeting cardiac tissue and proteins.

Other possible components

Many other possible components or factors have been suggested as possible etiologic causes for PPCM. These components include relaxin, prolactin, immune complexes, cardiac nitric oxide synthase, immature dendritic cells, and cardiac dystrophin.

The number of cases per live births is different from a country to another. In South Africa, the incidence was reported as 1 case per 1000 live births. However, in Japan the disorder affects 1 case per 6000 live births. Some countries, such as Nigeria, have a higher incidence than other countries because of some traditions, which involve the ingestion of big amounts of lake salt resulting in increased volume overload. Cases of PPCM were reported in different races. However, the risk is higher among African American women [13]. 

About 75% of PPCM cases in the United States are diagnosed during the first month after delivery. With 45% of these cases detected in the first week postpartum. Different incidences have been reported in the United States, ranging from 1 case per 15,000 live births to 1 case per 1300 live births [2].

PPCM was thought to be more common among women older than 30 years of age. However, it has been reported in all age groups. Probably the thought that the incidence is higher in women over the age of 30 is due to the increased risk of pulmonary edema in this age group because of the combination of pregnancy physiologic changes and some undiagnosed conditions, such as hypertension, thyrotoxicosis, or mitral stenosis.

Different mechanisms and components have been suggested and are currently being studied. However, the exact etiology as well as pathophysiology are still unknown.

A few lifestyle habits and changes (such as avoiding alcohol and cigarettes, eating a well-balanced diet with low fat, and exercising regularly) decrease the risk of developing PPCM and help in the prevention of the condition.

It is advised to consider birth control and prevent future pregnancies in women who were diagnosed with PPCM in a previous pregnancy, as these women have higher risk of developing the condition in future pregnancies.

Peripartum cardiomyopathy (PPCM) involves different features, including a decrease in the ejection fraction of the left ventricle, systolic dysfunction of the heart, thromboembolism, congestive heart failure, as well as a high risk of arrhythmias. Sudden cardiac death may also occur in PPCM patients. In affected individuals, the amount of blood pumped by the heart is not sufficient to cover the needs of the vital organs [1] [2] [3] [4] [5].

Thorough medical history and physical examination are required for the diagnosis of PPCM. Patients who are diagnosed with the condition have no previous history or other causes of heart disease. When all the other causes of heart failure are excluded, the diagnosis of PPCM can be made [1] [2] [3] [4] [5].

Many components and causes have been suggested for the development of PPCM and are currently being studied by researchers, which include viruses, toxins, autoimmune and genetic causes [1] [3] [6]. The condition usually begins with a trigger starting an inflammatory process within the heart, which could be a viral infection for example. The resultant process causes damage to the heart, which eventually leads to heart failure due to the deterioration in the function of the heart and its output [7].

In the early stage of PPCM, the condition may be asymptomatic; however, later on symptoms of heart failure develop including dyspnea, edema, shortness of breath, cough and chest pain.

The risk of developing the condition is higher among African American women; however, cases have been reported in different races. The prognosis differs from a woman to another depending on the time when the condition developed. In some cases, the prognosis can be bad and the disorder may lead to death. The management and treatment may include several components; in a multidisciplinary environment in order to improve the long term outcomes.

Peripartum cardiomyopathy (PPCM) is an uncommon condition, which usually develops during the last month of pregnancy or within the first five months after delivery of the baby, characterized by weakening in the heart muscle and an increase in its size.

Causes

The exact cause of PPCM is unknown, and there are different suggested causes that are being studied by researchers at the moment. However, the general idea is that there is a damage to the heart, which leads to weakening of the heart muscle.

Risk factors

There are many factors related to increasing the risk of developing PPCM in pregnant women, such as obesity, drinking alcohol, smoking cigarettes, poor diet, multiple pregnancies, the use of certain medications, previous history of disorders in the heart, and women with African American descent. It was thought that women over the age of 30 have higher risk of developing this condition. However, PPCM was reported in various age groups.

Symptoms

Initially, PPCM could be asymptomatic. However, heart failure symptoms may develop, which include fatigue, shortness of breath, cough, chest pain, swelling of the ankles, increased nighttime urination, and palpitations.

Diagnosis

The doctor is going to do a thorough physical examination of the body, including the lungs and the heart. In the physical examination, the doctor will look for abnormal signs related to PPCM mainly in the lungs and the heart. Further workup and investigations could be used as well, and they include a chest X-ray, chest CT-scan, echocardiogram, MRI of the heart, coronary angiography, nuclear heart scan, or a heart biopsy which is rarely done.

Treatment
Hospitalization for monitoring and effective management is required during the acute symptoms of PPCM. Several medications may be used in the treatment of the condition, such as digitalis, diuretics, and beta-blockers. Fluid restriction and low-salt diet may be recommended in some cases. If the medical management was unsuccessful, heart transplantation should be considered as an option.

Outcome

The outcome of PPCM differs from a woman to another. In some women the outcome is very good, especially if the heart size returns to normal after the delivery of the baby. However, in other cases the heart remains enlarged and it might lead to increased risk of heart failure in future pregnancies with a rate of death up to 50%.

Prevention

Eating a well-balanced diet with low fat, exercising regularly, and avoiding the risk factors such as smoking cigarettes and drinking alcohol will decrease the risk of developing PPCM and help in the prevention the condition. Birth control is advised in women who were diagnosed with PPCM in a previous pregnancy, as the risk of developing the condition in future pregnancies is increased in these women.

1. Pearson GD, Veille JC, Rahimtoola S, et al. Peripartum cardiomyopathy: National Heart, Lung, and Blood Institute and Office of Rare Diseases (National Institutes of Health) workshop recommendations and review. JAMA. March 2000; 283 (9): 1183–8. 
2. Elkayam U, Akhter MW, Singh H, et al. Pregnancy-associated cardiomyopathy: clinical characteristics and a comparison between early and late presentation. Circulation. April 2005; 111 (16): 2050–5.
3. Sliwa K, Fett J, Elkayam U. Peripartum cardiomyopathy. Lancet. August 2006; 368 (9536): 687–93. 
4. Murali S, Baldisseri MR. Peripartum cardiomyopathy. Crit. Care Med. October 2005; 33 (10 Suppl): S340–6. 
5. Phillips SD, Warnes CA. Peripartum Cardiomyopathy: Current Therapeutic Perspectives. Curr Treat Options Cardiovasc Med. 2004; 6 (6): 481–488.
6. Ansari AA, Fett JD, Carraway RE, et al. Autoimmune mechanisms as the basis for human peripartum cardiomyopathy. Clin Rev Allergy Immunol. December 2002; 23 (3): 301–24. 
7. Fett JD. Understanding peripartum cardiomyopathy. Int. J. Cardiol. October 2008; 130 (1): 1–2.
8. Felker GM, Thompson RE, Hare JM, et al. Underlying causes and long-term survival in patients with initially unexplained cardiomyopathy. N Engl J Med. 2000; 342: 1077–1084.
9. Midei MG, DeMent SH, Feldman AM, et al. Peripartum myocarditis and cardiomyopathy. Circulation. 1990; 81: 922–928.
10. Rizeq MN, Rickenbacher PR, Fowler MB, et al. Incidence of myocarditis in peripartum cardiomyopathy. Am J Cardiol. 1994; 74: 474–477.
11. Melvin KR, Richardson PJ, Olsen EG, et al. Peripartum cardiomyopathy due to myocarditis. N Engl J Med. 1982; 307: 731–734.
12. Sanderson JE, Olsen EG, Gatei D. Peripartum heart disease: an endomyocardial biopsy study. Br Heart J. 1986; 56: 285–291.
13. Gentry MB, Dias JK, Luis A, et al. African-American Women Have a Higher Risk for Developing Peripartum Cardiomyopathy. J Am Coll Cardiol. February 16, 2010. 55(7): 654-659.