Transcript Cardiomyopathy in pregnancy

• How to predict peripartum Cardiomyopathy ?
• What is the ideal anesthetic technique?
• Peripartum Cardiomyopathy (PPCM) was first
reported in the year 1849.
• How to predict it is CM?
• Development of cardiac failure in the last month
of pregnancy or within 5 months of delivery.
• Absence of a determinable etiology for the
cardiac failure.
• Absence of demonstrable heart disease before
the last month of pregnancy.
The Heart Failure Association of the European
Society of Cardiology defined it as
“ Idiopathic Cardiomyopathy presenting with
heart failure secondary to left ventricular
systolic dysfunction towards the end of
pregnancy or in the months following delivery,
where no other cause of heart failure is found.
It is a diagnosis of exclusion. The left ventricle
may not be dilated but the ejection fraction is
nearly always reduced below 45%."
Criteria for diagnosis of peripartum
cardiomyopathy
Risk factors:
-Advanced maternal age.
-Multiparity
-Afro-American race.
-Twin pregnancy
-Pre-eclampsia
-Gestational hypertension and diabetes.
-Use of tocolytics
-High sodium salt
-Deficiency of certain micronutrients
-Smoking during pregnancy
Pathophysiology:
-Myocarditis has been shown to be associated with PPCM although the incidence spans
a wide range
-Changes in immune function during pregnancy
exacerbated de novo infection or reactivated latent virus in the pregnant females
viral myocarditis
cardiomyopathy .
-Activation of autoimmune response . Sera from PPCM patients contain high
titres of autoantibodies against normal human cardiac tissue proteins that are not
present in the sera of patients with idiopathic cardiomyopathy .
-An abnormal cardiac response to hemodynamic changes associated with
pregnancy.
-A magnified decrease in left ventricle function in association with increase in
cardiac output and decrease in systemic vascular resistance which occurs in late
pregnancy can explain features of PPCM.
-An accelerated myocyte death (apoptosis), increase in proinflammatory
cytokines, excessive prolactin production and coronary microangiopathy. A few reports
of familial association of the disease have also appeared which may warrant further
evaluation for a probable genetic cause of the disease.
Drugs that should be avoided:
-Calcium channel blockers: They have a negative inotropic effect ,except
amlodepine, Amlodepine may be used if PPCM is associated with pre-eclampsia to
control blood pressure.
- ACE inhibitors: Both direct acting or receptor blockers, although the first line of
drug for patients in heart failure due to any cause, are however, contraindicated in
pregnant females due to the risk of fetal toxicity associated with them .
In Patient presents with acute failure
- Patient should be managed in an intensive care unit:
-Propped up position
-Continuous hemodynamic and oxygenation monitoring
-Central venous and arterial cannulation.
-Pulmonary artery wedge catheter (high dose of multiple cardiac drug infusions).
-Noninvasive ventilation with suitable positive end expiratory pressure (if oxygen by
simple face mask fails to improve SpO 2 more than 95%).
N.B.In case invasive ventilation is required:
Guard against aspiration in a pregnant patient should be taken.
-Nitroglycerine: to decrease afterload if the systolic blood pressure is more than 110
mm Hg. Nitroglycerin (NTG) intravenous infusion should be titrated to effect starting from
a dose of 10-20 μg/min up to a maximum of 200 μg/min.
N.B.(Nitroprusside is relatively contraindicated in pregnant patients due to risk of
thiocyanate and cyanide accumulation in the fetus).
-Dobutamine, dopamine and milrinone can be used to provide inotropic support to the
failing heart.
Levosimendan a cardiotropic agent that improves cardiac output by increasing the
response of myofilaments to intracellular calcium unlike the above mentioned
traditional inotropes that do so by increasing the intracellular calcium itself.
Levosimendan is used as an intravenous infusion at the rate of 0.1-0.2 μg/kg/min in
cardiac failure with or without a loading dose of 3-12 μg/kg over 10 minutes.
Mechanical assist devices and extracorporeal membrane oxygenators have been
used in these patients if medical therapy fails to improve cardiac status.
These devices can be used as bridging therapy as in most of the patients partial or
complete recovery can be expected within a year of delivery. Up to 11% of patients
will eventually require cardiac transplantation.
Intensive fetal monitoring : in hemodynamically unstable pregnant patients who are
on multiple drugs with continuous evaluation by obstetricians to prevent fetal loss.
Cardiologists, Anesthetists, Intensivists and Neonatologists
all actively involved in the obstetric management.
Pregnancy
reach term
emergent delivery
unless there is deterioration in the maternal or fetal well-being, there is no need for
urgent or emergent delivery and the pregnancy is allowed to progress to term
Mode of delivery
vaginally
C.S.
according to obstetric parameters or??? patient's wish.
Monitoring : continuous hemodynamic monitoring and
even invasive monitoring
-Effective labor analgesia is mandatory.
-
- Pain and anxiety associated with labor
increase sympathetic nervous system activity
increase in cardiac output and peripheral vascular resistance
increase in cardiac afterload decreases uteroplacental outflow
The hemodynamic goals of anesthesia are common IN all approaches:
- Reduce cardiac preload and afterload
- Prevent any decrease in the already compromised cardiac contractility.
- Intravenous and local anaesthetic drugs should be carefully titrated.
*Monitoring : Before commencement of anesthesia :
-Invasive monitoring including blood pressure and central venous pressure
- Pulmonary artery catheter and transesophageal echocardiography has been described
in patients with severely depressed cardiac function [
Regional anesthesia (RA) combined spinal epidural (CSE)
continuous spinal anesthesia (CSA)
continuous epidural anesthesia(CEA)
The method of choice as the sympathectomy associated with it causes a decrease in
cardiac preload and afterload which is beneficial in patients with PPCM.
-non-emergent cesarean section with relatively stable hemodynamics.
-Use of a catheter gives freedom of titrability of the local anaesthetic drug both in
epidural and intrathecal space.
-
RA, however, may be contraindicated in
anticoagulated patients .
-General anesthesia( GA):
-In moderately symptomatic patients or parturients undergoing
emergency surgery .
-For any urgent or emergent lower segment caesarean section (LSCS) .
-In patients with borderline cardiac decompensation , as even minor
degrees of sympathetic blockade associated with RA may lead to
fulminant cardiac failure .
Opioid-based anesthesia provides good hemodynamic control
and obtundation of response to endotracheal intubation
but may require postoperative ventilatory support for both mother and
neonate.
-Remifentanil was chosen for its efficacy in controlling intraoperative
stress response and rapid recovery independent of duration of infusion.
Use of other non-anesthetic drugs intraoperatively should be done with caution:
Ergometrine should preferably be avoided
oxytocin should be given as an infusion or slowly titrated to response.
Autotransfusion after delivery can be countered by a small dose of furosemide just before
delivery of the baby.
Favorable maternal and fetal outcome is not
dependent on anesthetic technique
BUT
*Strict hemodynamic control
* Meticulous cardiovascular Monitoring
*Close coordination between various involved specialists.
Questions:
1-Best choice of anesthesia ?
- Continuous
epidural
technique
2-Why ?
-
To avoid the complications of GA.
- decrease in cardiac preload and
afterload
3- Risks of GA ?
Carries with it the risks of sympathetic
stimulation during laryngoscopy.
-Use of a multi drug regime.
-Doubts about extubation.
-
4-Why Subarachnoid block can be
hazardous?
It can precipitate sudden and rapid
reductions in systemic vascular resistance and
there by preload.