Regional Anaesthesia in Peripartum Cardiomyopathy ( Con)

Dr.Manjusha Shah
Consultant Anaesthesiologist
Solapur

ABSTRACT
Peripartum cardiomyopathy (PPCM) is a rare but serious form of cardiac failure affecting women in the last months of pregnancy or early puerperium in previously healthy women. The incidence is 1:1500 to 1:4000 live births.
Risk factors include previous peripartum cardiomyopathy, hypertension, pre-eclampsia,obesity, diabetes, Afro-Caribbean origin, increased parity, older maternal age and multiple gestations.

The aetiology remains unclear but includes viral myocarditis, abnormal immune response to pregnancy or terbutaline tocolytic therapy.

Diagnosis is difficult as many symptoms are similar to those you would expect in the last trimester like peripheral oedema, fatigue and shortness of breath, atypical chest pains and hemoptysis. Clinical presentation of PPCM is similar to that of systolic heart failure from any cause, and it can sometimes be complicated by a high incidence of thromboembolism. Echocardiography has made diagnosis of PPCM easier and more accurateas there are strict echo criteria for diagnosis.Prompt recognition with institution of intensive treatment by a multidisciplinary team is a prerequisite for improved outcome.
Medical treatment of peripartum cardiomyopathy is similar to that for other dilated cardiomyopathies which includes salt restriction, diuretics, vasodilators, digoxin for arrhythmias.Management goals include preload optimization, afterload reduction, and increased contractility. Anticoagulation is also considered in many patients because of the significant risk of thromboembolism. As most cases present late in pregnancy delivery of the foetus may significantly improve symptoms.Patients should be monitored on a high dependency unit or cardiac care unit post-delivery.

Parturient with peripartum cardiomyopathy require special anesthetic care during labor,delivery and caesarean section. Invasive monitoring, including an arterial line and pulmonary artery catheter, should be utilized to assess the patient's hemodynamic status and guide management.Data from the pulmonary artery catheter is essential to determine the appropriate pharmacologic therapy for each patient.

Anesthetic management is similar for any patient with heart failure presenting for caesarian section regardless of etiology.Hemodynamic goals include maintainance of normal to low heart rate which definitely decrease oxygen demand and prevent large swings in blood pressure.The patient's hemodynamic status should be carefully followed and fluid management as guided by data from the invasive monitors while the anaesthesia level is slowly raised.These goals can be achieved by giving either general or regional anesthesia.A subarachnoid block may better be avoided in these patients because of sudden onset of hemodynamic instability
associated with this technique may not be well tolerated in these fragile patients.Cardiac function depends on preload and afterload so if using regional anaesthesia it must be carefully titrated with invasive blood pressure monitoring.

General anesthesia is required when cesarean section is required because of no reassuring fetal status or acute maternal decompensation. Anesthetic drugs with myocardial depressant effects should be avoided.During GA important factors to keep in mind like use volatile agents that decrease LV contractility without dramatic vasodilatation.One should avoid agents that decrease preload and afterload as well as avoid agents that directly or indirectly increase heart rate and contractility like pancuronium, atropine, epinephrine, and ephedrine.Hypotension better treated with volume expansion and pure alpha adrenergic agonist. Replace Blood loss promptly.
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Induction and maintenance with a high-dose opioid technique is often preferred. If this technique is used, remifentanil is a good choice because its short half-life can minimize depressant effects on the neonate. Trained personnel must be available to manage neonatal depression whenever a high-dose opioid anesthetic is utilized.

Epidural anesthesia is a better choice may improve myocardial performance and the cardiac output by decreasing the systemic vascular resistance, thus reducing the after load on the left ventricle without impairing contractility.
Monitoring with a central venous catheter is adequate with noninvasive BP monitoring. Oxytocin infusion is preferable. It also helps to decrease the after load maintaining the hemodynamic stability. Postoperativelyit is better to monitor these patients in an ICU for hemodynamic stabilization
The outcome is highly variable. Some develop persistent disease while some return to normal state slowly. These patients have a better survival rate than other types of cardiomyopathy. These patients may be counselled against subsequent pregnancies due to the high risk of mortality.