Improving Mortality in Cardiogenic Shock From Spontaneous Coronary Artery Dissection With Percutaneous External Heart Assist: A Case Report

Abstract

INTRODUCTION: Spontaneous Coronary Artery Dissection (SCAD) as a complication of pregnancy occurs during the third trimester or in the early postpartum period. This condition affects only one in 20,000-30,000 deliveries, but carries a mortality rate reported between 38-82%. SCAD can present as sudden cardiac death or cardiogenic shock. CASE PRESENTATION: A 39-year-old G6P5 (gravida 6, para 5) woman, with no cardiac risk factors presented with cardiac arrest 10 days after an uncomplicated vaginal delivery. Prior to the cardiac arrest, she complained of severe retrosternal chest pain. Assessment by paramedics demonstrated anterolateral S-T segment elevations on electrocardiogram and the cardiac rhythm rapidly progressed to ventricular fibrillation. Cardiopulmonary resuscitation was performed per protocol for approximately 20 minutes. On arrival to the hospital, she was immediately taken for a coronary angiography. Her heart rate was 80 beats per minute and she had a systolic blood pressure of 70mmHg. Coronary angiographic and intravascular ultrasound examination demonstrated a 60% stenosis in the left main coronary artery caused by a dissection extending into the proximal and mid-left anterior descending artery causing a 100% stenosis. A 50% stenosis was also observed in the proximal circumflex coronary artery. These findings were consistent with a spontaneous coronary artery dissection (SCAD). Intracoronary stents were placed in these four locations. Echocardiogram demonstrated an ejection fraction of 20% with akinesis of the cardiac septum, anterior wall and apex. As a result, both a temporary intra-aortic balloon pump (IABP) and a temporary pacemaker were placed. Despite these interventions and maximal hemodynamic support, the patient's cardiac output and mean arterial pressure remained low. For this reason, a percutaneous external heart assist (Impella) device was placed to maintain a cardiac output of 2.2L/minute and stabilize the patient. DISCUSSION: Cardiogenic shock is associated with a mortality of approximately 60-70%. With early revascularization and IABP therapy, mortality occurs in approximately 45-50% of patients with cardiogenic shock. Superior hemodynamic support with the Impella compared with the IABP has been established in studies, but no clear mortality benefit has thus far been demonstrated. CONCLUSIONS: We present the first case of SCAD with cardiogenic shock refractory to standard medical therapy and an IABP, where the addition of an Impella device improved the hemodynamics and thus patient's outcome.