Congenital heart disease

(CHD) found in pregnancy are Atrial aseptal defect (ASD), ventricular septal defect (VSD) patent ductus arteriosus (PDA) pulmonary stenosis aortic stenosis an tetralogy of Fallot.

The majority of these lesions should have been surgically corrected in childhood resulting in a growing population of women with CHD achieving a pregnancy. Uncorrected lesions may cause " pulmonary hypertension, cyanosis

severe left ventricular failure and are therefore present a greater risk in achieving successful pregnancy outcome. Congenital heart disease is also associated with increased fetal complications such as fetal loss, IUGR, pre-term birth and an increased risk of fetal CHD Particularly high-risk cardiac conditions for pregnancy include the following.

Eisenmenger's syndrome -A large leh–right shunt of blood is apparent usually through a VSD, ASD or PDA, which is still patent. -This results in an increase in the pulmonary blood flow, which over time leads to fibrosis and the development of pulmonary hypertension and cyanosis . When the right-sided heart pressures exceed leh heart pressures, the shunt reverses, with worsening cyanosis. Women with this condition are advised against pregnancy as maternal mortality lies in the region of 30–50%. Risk of prematurity contributes to the high perinatal mortality rate.

Marfan syndrome -This syndrome is caused by an autosomal dominant defect on chromosome 15. - It is a connective tissue disease affecting the musculoskeletal system, the cardiovascular system and eyes. The cardiovascular abnormalities are the most life-threatening as the elastic fibres in the media of the blood vessels weaken. - Dilatation of the ascending and descending aorta results, followed in some instances by dissection or rupture, or both. - Pregnancy poses a significant risk because of the increased stress on the cardiovascular system.

-There is a 50% chance of a child inheriting Marfan syndrome if one parent is affected. - Women who have minimal cardiovascular involvement and normal aortic root dimensions have a befer pregnancy outcome. - Careful monitoring is required throughout pregnancy, including the use of serial echocardiography to identify progressive aortic root dilatation. -Prophylactic antihypertensive therapy using beta-blockers is recommended to reduce blood pressure and the rate of aortic dilatation Robe. Some individuals with Marfan syndrome also present with dural ectasia which, unless mild, presents an increased risk of a spinal cerebrospinal fluid (CSF) leak in the case of accidental dural puncture during epidural:

- consequently, epidural anaesthesia is not usually recommended. -Whilst Marfan syndrome is a genetic condition, approximately 15% of cases are as a result of new mutation and thus some individuals remain undiagnosed and do not seek any preconception counselling. -Pregnant women with Marfan syndrome should be referred to the specialist team containing a cardiologist for immediate assessment and investigation.

Aortic dissection (acute) may occur in pregnancy in association with severe hypertension (systolic >160 mmHg) due to pre-eclampsia, coarctation of the aorta or connective tissue disease such as Marfan syndrome. The woman typically presents with severe chest or intrascapular pain. Early diagnosis using computed tomography chest scan, MRI or transoesophageal echocardiogram is critical, as maternal mortality is high.

Acquired heart disease -Rheumatic heart disease -inflammation and scarring of the heart valves and results in valve stenosis, with or without regurgitation. - The mitral valve is most ohen affected with stenosis, occurring in two-thirds of cases.

This condition is ohen diagnosed for the first time during pregnancy, presenting as severe breathlessness and tiredness. -It tends to appear in immigrant or refugee women who have not had access to medical care.

-Most women with valvular heart disease can be treated medically, aiming to reduce the heart's workload. -During pregnancy, this involves: - bed rest -oxygen therapy - use of cardiac drugs, e.g. diuretics (to reduce the fluid load) digoxin (to reduce and regulate the heart rate)

heparin (to reduce the risk of thromboembolic disease). Women with more severe symptomatic disease may require surgical intervention such as balloon valvuloplasty or valve replacement, although both of these procedures carry a degree of maternal and fetal mortality. Antibiotic prophylaxis is no longer recommended for all women with valvular lesions during labour although it may still be advisable for those who have mechanical valves.

Myocardial infarction and ischaemic heart disease -Myocardial infarction (MI) and ischaemic heart disease (IHD) are an increasing cause of maternal death . - Identifiable risk factors include: - increasing maternal age -obesity - diabetes -pre-existing hypertension - smoking, family history -poor socioeconomic status.

A myocardial infarction is most likely to occur in the third trimester of pregnancy and the peripartum period, - when haemodynamic changes are at their optimum creating a higher risk of thrombotic events due to the hypercoagulability induced by hormonal changes. - In the immediate postpartum period, spontaneous coronary artery dissection is the most common cause of MI.

- Typically, women present with ischaemic chest pain in the presence of an abnormal ECG and elevated cardiac enzymes, although these signs and symptoms may be masked during labour and birth -Atypical features include abdominal or epigastric pain and vomiting. Coronary angioplasty is the fine line therapy to improve the patency of blocked arteries

Peripartum cardiomyopathy -Peripartum cardiomyopathy is relatively rare but is potentially fatal, with mortality rates ranging from 25% to 50%. A number of these deaths occur shortly aher the onset of signs and symptoms. - The incidence of this type of cardiac disease varies from 1 : 300 to 1 : 4000 pregnancies, with heart failure developing very rapidly in some cases. -Predisposing factors to peripartum cardiomyopathy comprise of :

-multigravidae - multiple pregnancies - family history - ethnicity -smoking - diabetes -hypertension -pre-eclampsia -malnutrition - pregnant teenagers or older pregnant women and prolonged use of beta-agonists

-Commonly women have no previous history of heart disease and diagnosis is usually made within a specific period of time between the last month of pregnancy and the first 5 months postpartum -Inflammation and enlargement of the myocardium (cardiomegaly) give rise to leh ventricular heart failure and thromboembolic complications. - Presenting features include orthopnoea and dyspnoea, chest pain and palpitations, new resurgent murmurs and pulmonary crackles, raised jugular pressure, ankle oedema and fatigue.

-Treatment involves the use of oxygen, diuretics, and vasodilators to decrease pulmonary congestion and fluid overload, followed by inotropic agents to improve myometrial contractility and anticoagulation therapy.

As the cardiomegaly resolves there should be a corresponding improvement in the woman's condition but this process may take up to 6 months and there is a risk of recurrence in a subsequent pregnancy. -In some women, leh ventricular dysfunction persists and unless a heart transplant is performed mortality can be high