Pregnancy-related spontaneous coronary dissection revealing a fibromuscular dysplasia: a case report

¹Cardiology Department, Hedi Chaker Hospital, Faculty of Medicine of Sfax, Sfax, Tunisia, ²Cardiovascular Surgery Department, Habib Bourguiba Hospital, Faculty of Medicine of Sfax, Sfax, Tunisia

^&Corresponding author
Rania Hammami, Cardiology Department, Hedi Chaker Hospital, Faculty of Medicine of Sfax, Sfax, Tunisia

Introduction    

Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute coronary syndrome. It often affects young women, and it is responsible for non-negligible morbidity and mortality [1]. Through a spontaneous coronary artery dissection, with specially superposed predisposing and stressor factors, we propose to understand the physio-pathological mechanism, the etiologies, and the management of this entity.

Patient and observation     

Patient information: we report the case of a 32-year-old multigravida woman, with a history of aspirin allergy, who presented to the emergency room, one month after delivery, for breathlessness.

Clinical findings: at the interrogation, the patient reported intense chest pain during labor, which persisted a few hours later. The physical examination was normal apart from tachycardia.

Diagnostic assessment: the electrocardiogram showed Q waves in inferior leads. The chest radiography was unremarkable. The troponin was negative. Cardiac echography revealed a dilated left ventricle, globally hypokinetic with inferior akinesia, and a deteriorated systolic function with a left ventricle ejection fraction (LVEF) = 35%.

Diagnosis: we thought about cardiomyopathy of the peripartum, but the cardiac MRI showed an akinetic inferior wall with a late subendocardial enhancement. The coronary angiography showed a spiroid dissection of the right coronary beginning at the proximal segment with an aneurismal lesion in the middle segment and an image of addition in the left main related to an ulcerated plaque (Figure 1). The spontaneous coronary artery dissection was retained.

Therapeutic interventions: the angioplasty of the right coronary has been discussed. Considering antecedents of allergy to aspirin, the large size of the lesion, and the clinical stability of the patient, we opted for a medical treatment. The patient was treated with clopidogrel, we stopped heparin fearing an extension of the intra-parietal hematoma and we started heart failure treatment. The desensitization to aspirin was tried but failed twice. We performed many explorations in search of the etiology of SCAD. The echo-Doppler of the supra-aortic trunks as well as the CT scan of renal arteries were normal, but we discovered a fibromuscular dysplasia of the left external iliac artery. The immunologic and thrombophilia investigations were negative. The specialized clinical exam and the biological test did not reveal arguments in favor of an underlying chronic inflammatory pathology.

Follow-up and outcome of interventions: the control coronary angiography practiced 6 months later revealed the healing of the ulcerated lesion in the left coronary trunk and a partial improvement of the right coronary lesion (Figure 2). The echocardiography practiced at one year objectified a decrease in the size of the left ventricle with an improvement of the systolic function LVEF at 45%, but the inferior wall was akinetic with no viability on dobutamine echocardiography. Thus, we continue the medical treatment.

The patient's perspective: the patient appreciated the efforts of the clinical team and was happy to regain her sight. She promised to continue taking the treatment for heart failure and to avoid any new pregnancies.

Informed consent: the patient gave her informed written consent.

Discussion     

Spontaneous coronary dissection is a non-traumatic or iatrogenic separation of artery walls, creating a wrong lumen [1]. When relying on angiography, the incidence of spontaneous coronary dissection is variable, going from 0.07 to 1.1% [2,3]. It will be about 3 to 4% according to studies based on data from tomography with optical coherence (OCT) [2,4,5]. Thirty percent of SCAD occur in peripartum. The peak of occurrence coincides with the first two weeks of post-partum, but SCAD could happen even many months after delivery, especially in women still breastfeeding [6-8]. The differential diagnosis of Meadows syndrome is sometimes difficult because of the clinical context and the consequences on the systolic function of the left ventricle. In our case, the cardiac MRI had a great impact, the sub-endocardial localization of late enhancement was in favor of an ischemic cardiomyopathy, but during pregnancy, gadolinium could not be used, and then it will be difficult to make the true diagnosis. As a matter of fact, during pregnancy hormone changes especially estrogen and progesterone surges and hemodynamic variations with > 50% increase in cardiac output result in the weakening of the aortic wall which may extend to coronary [1,9]. During labor, the increase of intra-abdominal pressures could increase vascular shear stresses, leading to dissection.

The sophistication of etiologic investigation, in particular the systematic research of fibromyodysplasia has allowed us to better detect this pathology which has turned out to be a predisposing arteriopathy to coronary dissection. Saw et al. mentioned in a series of 168 patients with SCAD that 72% of cases were linked to fibromyodysplasia [10]. For retaining fibromyodysplasia as the etiology of coronary dissection, it is necessary to find at least another localization of the disease outside coronaries [11]. In our patient, the aneurismal aspect of the right coronary was evocative of the disease, but the artery pressure and kidney function were normal, and thoracic cerebral and abdominal imaging didn´t reveal other vascular localizations. Given the spontaneous tendency to the healing of lesions, the conservative strategy is generally proposed in stable patients under medical treatment with a normal coronary flow despite the dissection [8,12]. The anti-platelet treatment has shown useful in reducing thrombotic risk; however, some authors suggested an extension of intra-parietal hematoma with heparin therapy. Some teams stop heparin as soon as the angiographic confirmation of coronary dissection [1].

In patients with persistent chest pain, ischemia, or hemodynamic instability, percutaneous revascularization could be tried; but the rate of technical success is inferior to atherosclerosis lesions. This rate has not exceeded 30% according to Saw et al. review [10], it was 65% in the series of Tweet et al. [13]. The technical difficulties are multiple, such as the risk of passage of coronary guide through the false lumen, the risk of extension of dissection in the anterograde and retrograde direction, and the choice of stent. In our patient, we opted for medical treatment because of the clinical stability, the extent of the lesion, and the impossibility of prescribing aspirin resulting in a high risk of stent thrombosis.

Conclusion     

Spontaneous coronary artery dissection is a challenging diagnosis condition with no clear consensual management. The differential diagnosis with peripartum myocarditis or a Taku-Tsubo syndrome is sometimes difficult, and the cardiac MRI is very contributive. Through our case of SCAD within a young woman in the peripartum period, the methodical investigation revealed fibromyodysplasia. Thus, the etiologic investigation must be systematic to adapt the management to the pathology rather than the lesions.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Rania Hammami, Rahma Kallel: patient management, data collection. Rahma Kallel: manuscript drafting. Manuscript revision: Rania Hammami. All authors revised critically the paper and approved the final version of the manuscript.

Figures     

Figure 1: A, B) the coronary angiography: spiroid dissection of the right coronary and an image of addition in the left main related to an ulcerated plaque

Figure 2: A, B) the control coronary angiography practiced 6 months later: healing of the ulcerated lesion in the left coronary trunk and a partial improvement of the right coronary lesion

References