Maternal cardiac arrest is a very complex and demanding situation that requires the intervention of a multidisciplinary well-trained team [3]. Unfortunately, the incidence of maternal cardiac arrest is rising according to recent reports from the Netherlands, the United States and the United Kingdom [4,5,6]. The most common causes of maternal cardiac arrest are PE (24%), major obstetric hemorrhage (18%) and amniotic fluid embolism (16%) [3]. Other causes are severe preeclampsia and eclampsia, septic shock, complications of anesthesia and cardiac diseases [5,6,7]. Also, cardiac arrests occurring in emergency or in operating rooms are associated with higher maternal survival rates than those occurring in delivery rooms and maternity wards [7].
Pregnancy and postpartum are the most high-risk periods for venous thromboembolism events (VTE), mainly deep vein thrombosis, PE and cerebral thromboembolism. According to a French study on maternal deaths, PE is responsible of 9% of maternal deaths with 54% of these deaths occurring in the postpartum period [8]. Essentially, the risk of thromboembolic events seems to be more elevated in the postpartum period since more inflammatory and traumatic risk factors including cesarean section, postpartum hemorrhage and resuscitative hysterectomy, are associated with a pregnancy favorable background. According to a recent Cochrane review, no sufficient evidence is available to guide recommendations for thromboprophylaxis during pregnancy and during the postnatal period [9]. Despite an existing validated risk-stratification system for VTE in pregnancy and postpartum, it remains unclear whether a pharmacological and/or mechanical prophylaxis should be given for a high-risk parturient [10].
In this report, we tried to point out an unusual and insidious finding that occurred shortly after the delivery of a patient with placenta percreta. During cardiopulmonary resuscitation and given the sudden onset of events, a PE was highly suspected. After stabilization, an urgent pulmonary angiogram showed a bilateral massive PE. Indeed, diagnostic imaging should not be withheld nor postponed in pregnant or non-pregnant patients with suspected PE because of the fatal consequences of a misdiagnosis [11].
In our case, the patient presented multiple risk factors that could have contributed to the development of PE. The list includes immobilization and bed rest in the previous hospitalization, lack of prophylaxis for an immobilized pregnant patient with placenta percreta, family history, prolonged surgery, hypercoagulable state of pregnancy and previous use of contraceptive. Placenta percreta is an important factor not to be underestimated since a bulging placenta occupying the pelvis will promote a vein stasis and consequently the formation of vein thrombosis. Also, a general consensus is reached on the effectiveness of mechanical prophylaxis at reducing rates of VTE in obstetric patients with at least one large study showing a reduction in fatal PE [10]. However, it was not sufficient to prevent these events in the present case. Besides, due to the vaginal spotting in the PAS setting, a pharmacological anticoagulation was unfortunately contraindicated which might have contributed to the patient’s PE.
This case presentation is one of few cases of thromboembolic events in patients with placenta accreta. These cases are usually underreported because they are associated with a higher mortality rate. The first one to be mentioned was reported in late 1960s where a syncytial trophoblastic PE was presented in a patient with placenta increta and preeclampsia [12]. Like other types of emboli, a trophoblastic embolism can lead to catastrophic consequences causing sudden death [12,13,14]. Therefore, awareness of this syndrome and prompt action are necessary to prevent tragic consequences [13]. Also, the presence of placenta percreta may increase the risk of amniotic fluid embolus, as suggested by Styron et al. in their case presentation [15].
While some manifestations of PE will be limited to hypoxia, hypocapnia, and tachycardia, others will present suddenly with a cardiac arrest as in the present case. In contrast, other colleagues reported a case of cardiac arrest caused by PE preoperatively in a patient with placenta previa accreta who underwent a cesarean section immediately after cardiopulmonary resuscitation [16]. Using abdominal ultrasound, they demonstrated the presence of floating thrombus in the inferior vena cava [16]. A recently reported case showed similar findings of an incidentally found inferior vena cava thrombus by using an intraoperative transesophageal echocardiography (TEE) [17]. Similarly, an inferior vena cava filter was placed via an abdominal incision and external iliac vein catheterization since percutaneous vascular access was impossible and the operating room table was radio-opaque. Inferior vena cava filter placement aimed to prevent further embolic events.
TEE is a monitoring tool that helps to reveal the presence of new thrombus, enabling the operative team to be particularly vigilant for a PE [17]. To our knowledge, our case is the first reported case in the literature of an incidentally found thrombus in the right ventricle using TEE. TEE was performed simultaneously during the thoracotomy and had enabled us to detect at the end of the procedure the presence of a new free-floating thrombus in the right atrium and right ventricle, requiring the initiation of a second extracorporeal circulation and embolectomy. In fact, the second thrombus could not be detected and could have led to the patient’s death, if no TEE was performed. This is to emphasize the importance of a multidisciplinary team that enabled the early detection of thrombosis, and consequently, an urgent transfer of the patient in the operation room to receive a salvage embolectomy. That’s why these kinds of cases need to be addressed in centers of excellence where expertise and multidisciplinary teams are available to manage the most serious complications [18, 19].
Placenta percreta is not only the surgeon’s nightmare but also involves the anesthesiologist. Aside from hemorrhagic risk, these cases can be complicated with massive and fatal thromboembolic events. A preoperative screening for deep venous thrombosis could be recommended. However, given the lack of convincing evidence and recommendations to prevent thromboembolic events, it is highly required to determine focus and allocate efforts for quality improvements in obstetric health care: patients with placenta percreta should always be referred to tertiary care centers that grant access to multidisciplinary team management. Only then, you can hope “they will live twice”.