Peripartum Cardiomyopathy

Peripartum cardiomyopathy
Other names: Post-partum cardiomyopathy[1]
Normal heart (left) compared with one with peripartum cardiomyopathy (right)
Specialty	Obstetrics, cardiology
Symptoms	Shortness of breath, tiredness, leg swelling, palpitations[2]
Complications	Arrhythmias, blood clots, fetal distress[3]
Usual onset	Last month of pregnancy to 5 months after delivery[1]
Causes	Unknown[2]
Risk factors	Age>25; high blood pressure; multiple gestations; family history[2][3]
Diagnostic method	Based on symptoms and ultrasound; after ruling out other possible causes[2][3]
Differential diagnosis	Symptoms of pregnancy, preeclampsia, myocarditis, valvular heart disease, other cardiomyopathies[2][3]
Treatment	Timely delivery, implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT)[2]
Medication	Beta-blockers, thiazide diuretics, furosemide[2]
Prognosis	Over half recover within 6 months[3]
Frequency	1 in 2,200 pregnancies (USA)[2]
Deaths	7 to 50%[4]

Peripartum cardiomyopathy (PPCM) is a type of dilated cardiomyopathy which presents between the last month of pregnancy and five months after deliver.^[1] Symptoms are those of heart failure, with shortness of breath, tiredness, and swelling.^[2] Other symptoms may include palpitations, chest pain, or dry cough.^[2][3] Onset may be gradual or sudden.^[2] Complications can include arrhythmias, blood clots, fetal distress, and sudden death.^[3][2]

The cause is unknown, and previously healthy women can be affected.^[2] Risk factors include hypertensive disorders of pregnancy, multiple gestations, and family history.^[2][3] The underlying mechanism involves systolic dysfunction of the heart resulting in decreased left ventricular ejection fraction (EF) typically below 45%.^[2] Diagnosis is based on symptoms and a heart ultrasound; after ruling out other possible causes.^[2][3]

Delivery in a timely manner may be recommended.^[2] Before delivery, treatments may include beta-blockers, thiazide diuretics, or furosemide.^[2] After delivery, management is similar to typical heart failure.^[2] An implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT) may be another option; though an external device may be used as over half improve over six month.^[2][3] Recovery may require five years; with a risk of death of 7 to 50%.^[2][4] There is a risk it may recur in future pregnancies, and thus these may be recommended against.^[5]

Peripartum cardiomyopathy affected about 1 in 2,200 pregnancies in the United States, with rates as high as 1 in 300 in Haiti.^[2] Those over the age of 25 or 30 years are more commonly affected.^[3][5] Being African is also a risk.^[3] The condition was first defined in 1971 by Demakis; though, had been recognized since the 1700s.^[6][7]

Signs and symptoms[edit | edit source]

Symptoms usually include one or more of the following: orthopnea (difficulty breathing while lying flat), dyspnea (shortness of breath) on exertion, pitting edema (swelling), cough, frequent night-time urination, excessive weight gain during the last month of pregnancy (1-2+ kg/week; two to four or more pounds per week), palpitations (sensation of racing heart-rate, skipping beats, long pauses between beats, or fluttering), chest pain or tightness, fatigue and light-headedness.^[8][9][10]

The shortness of breath is often described by PPCM patients as the inability to take a deep or full breath or to get enough air into the lungs. Also, patients often describe the need to prop themselves up overnight by using two or more pillows in order to breathe better. These symptoms, swelling, and/or cough may be indications of pulmonary edema (fluid in the lungs) resulting from acute heart failure and PPCM.^{[citation needed]}

Physical examination may reveal jugular venous distention, displaced apical impulse, a third heart sound, murmur consistent with mitral regurgitation, tachypnea, tachycardia, pulmonary rales, and peripheral edema.^[3][11]

Diagnosis may be delayed or dismissed as early symptoms may be interpreted as being typical of normal pregnancy. Delays in diagnosis and treatment of PPCM are associated with increased morbidity and mortality.^{[8][9][12][13][14][15]}

It is also quite common for women to present with evidence of having an embolus (clot) passing from the heart to a vital organ, causing such complications as stroke, loss of circulation to a limb, even coronary artery occlusion (blockage) with typical myocardial infarction (heart attack).^[16]

Peripartum cardiomyopathy is now a leading cause of maternal death in many parts of the United States and around the world.^[17][18] Approximately 60% of cases of cardiogenic shock during pregnancy or in the early postpartum period are caused by peripartum cardiomyopathy.^[19]

A high suspicion of PPCM is required in any peri- or postpartum patient where unusual or unexplained symptoms occur.^{[8][9][20][21][16]}

Diagnosis[edit | edit source]

The following screening tool may be useful to patients and medical professionals in determining the need to take further action to diagnose symptoms:^[22]

Look for early symptoms of heart failure during last month of pregnancy:
1. Difficulty breathing while lying flat:
a.) None = 0 points; b.) Need to elevate head = 1 point; c.) Need to elevate upper body 45° or more = 2 points
2. Dyspnea (shortness of breath) on exertion:
a.) None = 0 points; b.) Climbing 8 or more steps = 1 point; c.) Walking on level = 2 points
3. Unexplained cough:
a.) None = 0 points; b.) Night-time = 1 point; c.) Day and night = 2 points
4. Swelling (pitting edema) lower extremities:
a.) None = 0 points; b.) Below knee = 1 point; c.) Above and below knee and/or hands/face = 2 points.
5. Excessive weight gain during last month of pregnancy:
a.) Under 2 pounds per week = 0 points; b.) 2 to 4 pounds per week = 1 point; c.) over 4 pounds per week = 2 points.
6. Palpitations (sensation of irregular heart beats):
a.) None = 0 points; b.) When lying down at night = 1 point; c.) Day and night, any position = 2 points
Scoring and Action:
0 – 2 = low risk — continue observation
3 – 4 = mild risk — consider doing blood BNP and CRP; echocardiogram if BNP and CRP are elevated
5 or more = high risk — do blood BNP, CRP, and echocardiogram

Initial evaluation should include blood work. PPCM is a diagnosis of exclusion, meaning that other conditions need to be evaluated and ruled out before this diagnosis will be used. Anemia, electrolyte abnormalities, thyroid dysfunction, and renal or liver dysfunction need to be ruled out. Further testing can also include a chest x-ray, brain natriuretic peptide levels, EKG, echocardiogram, cardiac MRI, and cardiac catheterization. There is no specific test to get a diagnosis of PPCM.^[3]

Ultrasound[edit | edit source]

• Ultrasound of peripartum cardiomyopathy^[23]

• Ultrasound of peripartum cardiomyopathy^[23]

• 

  Ultrasound of peripartum cardiomyopathy^[23]

Treatment[edit | edit source]

Early detection and treatment are associated with higher rates of recovery and decreased morbidity and mortality.^[8][9][12]

Treatment for PPCM is similar to treatment for congestive heart failure. Conventional heart failure treatment includes the use of diuretics, beta blockers (B-B), and angiotensin-converting enzyme inhibitors (ACE-I) after delivery. Diuretics, preferably furosemide, help the body to get rid of excess water weight and also lower blood pressure. Fluid restriction is also used to help limit excess water in the body. Using diuretics during pregnancy needs to be done carefully, as diuretics can impair blood flow to the placenta which could potentially cause harm to the fetus. Hydrochlorothiazide and furosemide are safe during pregnancy and breastfeeding.^[3] ACE-I and B-B improve blood circulation and contribute to the reversal of the immune system dysfunction associated with PPCM. If ACE-I is not well tolerated by the patient, it can be replaced by angiotensin receptor blockers (ARB). ACE-I and ARBs are contraindicated during pregnancy and breastfeeding, but can be used during the postpartum period as long as breastfeeding is not occurring.^[3] Hydralazine with nitrates may replace ACE-I in breastfeeding mothers or before delivery; however, evidence suggests that this course of treatment may not be as effective as ACE-I but beneficial when necessary.^{[8][9][12][13][20][15][24]}

If EF is less than 35%, anticoagulation is indicated, as there is a greater risk of developing left ventricular thrombi (blood clots). Sometimes implantation of a left ventricular assist device (LVAD) or even heart transplant also becomes necessary.^{[8][12][13][20][25]}

It is important that the patient receives regular follow-up care including frequent echocardiograms to monitor improvement or the lack thereof, particularly after changes of medical treatment regimes.

People who do not respond to initial treatment, defined as left ventricular EF remaining below 20% at two months or below 40% at three months with conventional treatment may merit further investigation, including cardiac magnetic resonance imaging (MRI), cardiac catheterization, and endomyocardial biopsy for staining and for viral polymerase chain reaction (PCR) analysis. Antiviral therapy, immunoabsorption, intravenous gamma globulin, or other immunomodulation therapy may then be considered accordingly, but following a controlled research-type protocol.^[20]

Since no one knows for sure exactly when to discontinue treatment, even when recovery occurs quickly, it is still recommended that both ACE-I and B-B be continued for at least one year after diagnosis.^[9] When considering discontinuing heart failure medications, they should be weaned gradually over time and patients should be closely monitored during this time.^[11]

There is an increased risk of sudden death and they benefit from implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy. However, as reversible, sometimes implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy (CRT) are not routinely used and reserved for severe LV dysfunction or high risk cases.^[26]

Bromocriptine is being studied as another potential treatment option, due to its interference with the prolactin pathway which may cause PPCM for some people.^[27] Several studies have shown bromocriptine in addition to standard heart failure medications produce better outcomes in terms of both overall recovery and rate of recovery.^[11]

Prognosis[edit | edit source]

The most recent studies indicate that with newer conventional heart failure treatment consisting of diuretics, ACE inhibitors and beta blockers, the survival rate is very high at 98% or better, and almost all PPCM patients improve with treatment.^[24][28][29] In the United States, over 50% of PPCM patients experience complete recovery of heart function (EF 55% or greater).^[12][20] Almost all recovered patients are eventually able to discontinue medications with no resulting relapse and have normal life expectancy.^[28]

It is a misconception that hope for recovery depends upon improvement or recovery within the first six to 12 months of diagnosis. Many women continue to improve or recover even years after diagnosis with continued medicinal treatment.^[9][30] Once fully recovered, if there is no subsequent pregnancy, the possibility of relapse or recurrence of heart failure is minimal.^[24][29]

Subsequent pregnancy should be avoided when left ventricular function has not recovered and the EF is lower than 55%.^[8][31] However, many women who have fully recovered from PPCM have gone on to have successful subsequent pregnancies.^[20] A significant study reports that the risk for recurrence of heart failure in recovered PPCM patients as a result of subsequent pregnancy is approximately 21% or better.^[31] The chance of relapse may be even smaller for those with normal contractile reserve as demonstrated by stress echocardiography.^[32][33] In any subsequent pregnancy, careful monitoring is necessary. A stress test or echocardiogram should be complete prior to a subsequent pregnancy. Where relapse occurs, conventional treatment should be resumed, including hydralazine with nitrates plus beta-blockers during pregnancy, or ACE-inhibitors plus beta-blockers following pregnancy.^{[citation needed]}

Some factors that are associated with a better prognosis are small left ventricle diastolic dimension, LVEF greater than 30-35% at time of diagnosis, absence of troponin elevation, absence of LV thrombus, non-African American ethnicity. Some factors that indicate a poor prognosis are a QRS greater than 120 milliseconds, a delay in diagnosis, high NYHA class, multiparity, African descent.^[3]

Mortality estimates have significant differences depending on the racial group being studied, the geographical location, and the length of follow-up in the study. At 1 year follow-up in the United States, mortality rates range from 4%-11%.^[11]

Epidemiology[edit | edit source]

PPCM occurs in between 1 in 1300 to 4000 live births in the United States.^[8][30][34] While it can affect women of all races, it is more common in some countries; with estimates of one in 1000 live births in South African Bantus, and as high as one in 300 in Haiti.^[14][30]

PPCM may be slightly more common among older women who have had higher numbers of liveborn children and among women of older and younger extremes of childbearing age.^[14][34] However, a quarter to a third of PPCM patients are young women who have given birth for the first time.^{[35][9][14][30][36][37][excessive citations]}

While the use of tocolytic agents or the development of preeclampsia (toxemia of pregnancy) and pregnancy-induced hypertension (PIH) may contribute to the worsening of heart failure, they do not cause PPCM; the majority of women have developed PPCM who neither received tocolytics nor had preeclampsia nor PIH.^[30][36]

When looking at the occurrence of PPCM worldwide, the incidence of PPCM is well correlated with maternal mortality rates. This means that in areas with higher maternal mortality, there are also higher rates of PPCM. This suggests that the level of perinatal care may impact the incidence of PPCM.^[38]

Though any racial background, any age, and any pregnancy may be affected.^[31]

References[edit | edit source]

External links[edit | edit source]

Classification	ICD-10: O90.3 ICD-9-CM: 674.5 DiseasesDB: 29243
External resources	MedlinePlus: 000188 eMedicine: med/292 Orphanet: 563