Emergency cesarean section in peripartum cardiomyopathy.

Peripartum cardiomyopathy (PPCM) is defined as onset of acute heart failure without demonstrable cause in last trimester of pregnancy or within the first 6 months after delivery. We report a case of PPCM with left ventricular ejection fraction less than 25% who had reported to us at 38 weeks of gestation for emergency caesarean section managed with graded epidural anaesthesia. PPCM is a form of dilated cadiomyopathy with left ventricular systolic dysfunction that results in signs and symptoms of heart failure.

INTRODUCTION

Peripartum cardiomyopathy (PPCM) is defined as the onset of acute heart failure without demonstrable cause in the last trimester of pregnancy or within the first 6 months after delivery. The incidence is approximately 1 per 3000 to 1 per 4000 live births and mortality ranges from 30–60%.[1] The etiology of PPCM remains unknown. Proposed causes include myocarditis of normal immune response to pregnancy and maladaptive response to the hemodynamic stresses of pregnancy. We report a case of PPCM (LVEF< 25%) for emergency caesarean section managed with graded epidural anesthesia.

CASE REPORT

A 27-year Muslim female weighing 75 Kg second gravida presented at 38 weeks of gestation in cardiac failure for emergency caesarean section for the fetal heart rate drop. She was a diagnosed case of PPCM within six months of her first delivery 2 years back. She was immediately started on therapy, details of which were not available. However, she discontinued therapy as she was asymptomatic and features of cardiac failure reappeared in the third trimester of this pregnancy. At this admission, she presented with complaints of increasing fatigability with difficulty in breathing and severe dyspnoea on the minimal physical activity. The patient was started on anti failure therapy including bed rest, propped up position, oxygen supplementation and once daily Tab.Lasix 40 mg, Tab. Digoxin 0.25 mg and Tab.Spiranolactone 50 mg. At preanesthetic evaluation it was noted that the patient was orthopneic with a pulse rate of 150/min., blood pressure of 100/70 mm Hg, and SpO2 was 98% on FiO2 of 0.4 and ABG did not reveal metabolic or respiratory acidosis. She had pitting pedal edema in both legs and auscultation of the lungs revealed bilateral basal crepitations. The ECG showed sinus tachycardia with ST depression and chest X-ray revealed massive cardiomegaly with basal haziness on the right side. A cardiology consultation had been obtained. Echocardiography revealed generalized hypokinesia, moderate left ventricular dysfunction with LVEF < 25% and huge cardiomegaly (transthoracic ECHO showed dilated ventricle with left ventricular dimension measuring more than 6 cm). The anesthetic plan was a continuous lumbar epidural anesthesia with titrated doses of local anesthetic with opioid, carefully monitoring the blood pressure response. Accordingly on arrival to the operation theatre monitors were connected and baseline values of pulse rate, blood pressure and room air saturation noted. An 18 g IV cannula was placed and careful volume infusion was given with Ringer's lactate at 4 mL/kg/h monitoring BP, PR, saturations and lung auscultation for crepts and ronchi. In sitting position, taking aseptic precautions, an epidural catheter was placed in L2–L3 space and after test dose, 6 mL of Lignocaine 2% with Fentanyl 50 μg. was given. Adequate analgesia was seen up to T8 level after 15 min. She was then placed in supine position with a wedge inserted under the right hip to minimize aorto-caval compression. As T6 sensory block was targeted, fractionated doses of 2% Lidocaine was given to get a level of T6. The patient was hemodynamically stable and once adequate level was confirmed, surgery was proceeded with and a live child was delivered weighing 3.5 kg with APGAR score of 5 and 7 at one and 5 min, respectively. The procedure took 40 min. and the patient was stable and end – operatively her pulse rate was 120/min, BP 90/60 mm Hg with sensory level of T8. She was shifted to the ICU for observation and further management and kept in propped up position with oxygen through the venturi mask. Postopertive analgesia was given through epidural using Morphine 3 mg in normal saline.

DISCUSSION

PPCM is a form of dilated cardiomyopathy with left ventricular systolic dysfunction that results in signs and symptoms of heart failure. Treatment goals include preload and after load reduction and increase the contractile force of the heart. Combination of hydralazine and amlodipine provide after load reduction, while diuretics and nitro-glycerin can be used for the pre load reduction. Oral inotropic therapy is provided by digoxin. The parturients cardiac status is stabilized with medical therapy as was done in our patient.[2] Anticoagulation therapy has been advocated in patient with EF <35% to avoid risks of thromboembolism.[3] Hemodynamic goals include the maintenance of normal to low heart rate to decrease oxygen demand and prevention of large swings of blood pressure. During general anesthesia important factors to keep in mind are: volatile agents that preserve LV contractility without dramatic vasodilatation are desirable, and drastic changes in preload and after load have to be avoided, for example, hypovolemia, nitroprusside, and nitroglycerine. Agents that directly or indirectly increase heart rate and contractility, for example, pancuronium, atropine, ephedrine, and epinephrine have to be avoided or used with caution. Blood loss has to be replaced promptly and hypotension may be better treated with volume expansion and pure alpha adrenergic agents. While CVP monitoring may be useful in titrating fluids, we have to remember that insertion of CVP / PAC may induce atrial or ventricular dysrhythmia and also delays the delivery of the baby further compromising fetal well being. Our choice of epidural was to prevent complications of GA, use of multidrug regime and problems associated with extubation.

Regional techniques reduce after load with minimal effect on contractility, thus improving cardiac output and reducing myocardial work.[4] Sympathectomy induced after load reduction that occurs with epidural anesthesia may improve myocardial performance in these patients. Breen et al. reported a successful outcome in a 14-year-old parturient with pulmonary hypertension and PPCM and patent foramen ovale for LSCS by giving lumber epidural with lidocaine and Fentanyl as was done in our patient.[5] Though CSE is an option, we believe that it can cause precipitous fall in blood pressure and a continuous epidural with titrated dosing can provide a better control over hemodynamic and probably a better choice in this patient.

Shrestha et al. reported a case of PPCM with ejection fraction of 18% brought for the emergency caesarian section.[6] The patient had a successful outcome using epidural with Lidocaine 2% and adrenaline.

PPCM is a severe form of heart failure that causes significant mortality. Once diagnosed, medical management must address the classical goals of heart failure therapy and should include consideration of thrombo embolic prophylaxis.

Subarachnoid block can be hazardous or it can precipitate sudden and rapid reduction of systematic vascular resistance and thereby preload. GA has its disadvantages of sympathetic stimulation and polypharmacy. Hence, graded epidural anesthesia appears to be the technique of choice for patient with PPCM.