الفهرس 
Definition and pathophysiology of peripartum cardiomyopathyOnly 14 pages are availabe for public view
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Abstract
One of the most severe heart diseases related to pregnancy is peripartum cardiomyopathy (PPCM). Peripartum cardiomyopathy (PPCM) is an uncommon, idiopathic complication of pregnancy associated with 10–30% mortality.
The European Society of Cardiology Working group on PPCM defines the disease as heart failure (HF) symptoms secondary to new left ventricular (LV) systolic dysfunction developing during the last months of pregnancy or within the immediate postpartum period. It occurs in the absence of an identifiable cause for HF with reduced ejection fraction (HFrEF) and represents a diagnosis of exclusion.
There are several risk factors and conditions associated with development of PPCM including; age, race, preeclampsia and multiple gestations. Other associated conditions have been reported but less well substantiated, including substance abuse, anemia, asthma, prolonged tocolysis, diabetes mellitus, obesity, and malnutrition.
There are many hypothesis including myocarditis, genetic succeptibility, fetal microchimerism, and autoimmune response, A ‘two- hit’ model of angiogenic imbalance in the heart during the peripartal period has recently been proposed, combining systemic antiangiogenic signals during late pregnancy and host susceptibility through insufficient local proangiogenic defences in the heart.
Pregnancy is a physiological state accompanied by maternal hemodynamic changes, during which time, signs and symptoms could
mimic signs of heart failure. Awareness of these changes is of great importance for early recognition and timely management of PPCM, which correlate with better prognosis of these patients. Symptoms of PPCM, such as dyspnea, cough, fatigue, leg edema, malaise, are very often misinterpreted as physiological symptoms due to pregnancy. This is the reason of delayed recognition of PPCM, so at the moment of diagnosis patients are presented with NYHA III or IV functional class.
Transthoracic echocardiography is the most important tool for diagnostic confirmation or exclusion of PPCM and should be performed in every suspected case. Echocardiography enables prompt diagnosis and the evaluation of heart function. Thus, in any case of doubt or suspicion of heart failure, bed-side echocardiography should be done as soon as possible. PPCM is presented with systolic dysfunction, reduced cardiac output, and increased filling pressures, while left ventricular dilatation must not be always present. Echocardiographic diagnostic criteria for PPCM include: EF <45%, LVFS <30% or both, and LVEDD
>2.7 cm/m2 body surface area. Valvular regurgitation can be present. In patients with EF ≤35%, left ventricular thrombus is often detected.
Current guidelines recommend treatment as with other forms of HFrEF but with consideration for the unique and potential teratogenic effects of guideline-directed medical therapy (GDMT). Similarly, care is taken to avoid any potential toxic exposures to the breastfeeding newborn during the postpartum period.
In combination with β-blockers, angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) are the backbone of HFrEF therapy because they reduce morbidity and mortality. However, in fetal development, inhibition of the renin-angiotensin-
aldosterone system can produce deleterious complications. Multiple studies have evaluated the use of over 12 different ACEIs and six different ARBs in pregnancy.
Novel treatment included bromocriptine’s inhibition of prolactin secretion and pentoxifylline that may improve HF symptoms by inhibiting production of tumor necrosis factor-α, a negative inotrope.
Patients with signs of cardiopulmonary distress and/or circulatory shock need rapid and more aggressive therapy and should be admitted to the intensive cardiac care unit. Initial therapy includes five main elements: optimization of the preload; optimization of oxygenation; restoration of haemodynamics with inotropes and/or vasopressors; urgent delivery if heart failure occurs during pre-partum; and consideration of adjunctive therapies with bromocriptine.
Implantation of a mechanical circulatory support should be considered early as a rescue therapy in patients who cannot be stabilized with medical therapy alone. If necessary, a device for temporary support should be implanted in the acute phase, either as ‘bridge-to-recovery’, if ventricular function improves during the subsequent days and weaning can be achieved, or as ‘bridge-to-bridge’, if haemodynamic impairment persists and circulatory support has to be ensured by switching to a more durable (and usually more invasive) device. Because of the higher proportion of patients with at least partial recovery of ventricular function compared with other cardiomyopathies, an initial ‘bridge-to- transplantation’ strategy is seldom necessary.
For the choice of the initial device, several factors should be taken into account (needed haemodynamic support, periprocedural risks, costs),
but the oxygenation status of the patient plays a central role. If the patient is adequately oxygenated, percutaneous [e.g. intra-aortic balloon pump (IABP), Impella®] or surgical (e.g. CentriMag®, AbiomedBVS 5000®) devices can be used to restore circulation. In contrast, in the presence of impaired oxygenation, other devices with integrated oxygenation should be used [e.g. TandemHeart®, veno-arterial extracorporeal membrane oxygenation (ECMO)].
Novel therapies, such as the wearable cardioverter-defibrillator (WCD) (LifeVest®, Zoll, Pittsburgh, PA, USA) are an interesting alternative for the prevention of sudden cardiac death in the first months after diagnosis, until a definitive decision about ICD implantation can be made.
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.
Left ventricular recovery and function are considered the most reliable prognostic factors and predictors of survival in subsequent pregnancies. Future pregnancies are not recommended in women with persistent heart failure, because the heart most likely would not be able to tolerate the increased cardiovascular workload associated with the pregnancy.