Spontaneous Coronary Artery Dissection Postpartum

Spontaneous Coronary Artery Dissection (SCAD) is a rare but increasingly reported cause of myocardial infarction and sudden death. Pretty first described SCAD in 1931 at autopsy in a 42-year-old woman who died after presenting with chest pain.1 About 150 cases have been described in the English literature.2,3 Eighty percent of these cases occurred in women, many of whom were pregnant or in the peripartum period.4 SCAD frequently affects young, healthy women who have no risk factors for coronary artery disease. The etiology of SCAD remains unclear. Although usually fatal, there are reports of successful medical and surgical intervention. We report the first case of SCAD in the postpartum period that was treated successfully with stenting and a glycoprotein (GP) IIb/IIIa inhibitor. There have only been three other published reports on the use of coronary stenting for SCAD in pregnancy and postpartum period2,5,6 and only one with the use of a GP IIb/IIIa inhibitor alone.7 Case Report. A 35-year-old caucasian woman, gravida 6, para 6, who was two weeks postpartum, was admitted to the hospital with an acute onset of severe chest pain at rest. The pain was midsternal, associated with shortness of breath and diaphoresis. Her pregnancy was uncomplicated and she had a normal vaginal delivery. Her past medical history was significant for borderline hypertension which was not treated medically. Her initial electrocardiogram revealed a myocardial injury pattern with ST elevation in leads I, aVL and V2, with reciprocal ST depression in the inferior leads and poor R wave progression in leads V1–V6 (Figure 1). She was treated with intravenous nitrates, heparin, tenecteplase, and clopidogrel. Aspirin was held due to a reported allergy. Despite this treatment the chest pain reoccurred with dynamic EKG changes and she was transferred to our hospital for emergency coronary angiography. Her blood pressure was 131/79 mmHg, with a pulse of 109 beats per minute (bpm). There were no stigmata of a connective tissue disease or marfanoid habitus. Cardiac examination was unremarkable for murmurs, rubs or gallops. The lungs were clear bilaterally. Her initial hospitalization was complicated by ventricular tachycardia and fibrillation, which responded to external defibrillation and infusions of lidocaine and amiodarone. After receiving eptifibatide, she was emergently transferred for coronary angiography. Cardiac catheterization revealed a major dissection in the left anterior descending artery throughout its proximal segment to the midsegment with retrograde thrombosis (Figure 2). The other coronary arteries were free of any disease. The left ventricle had mild dyskinesis in the anterolateral and inferoapical segments. The ejection fraction (EF) was 45%. The area of dissection in the LAD was easily crossed with a guide wire. A 3 mm/15 mm length balloon was placed into the mid portion of the LAD and inflated on two occasions. Repeated injections revealed an improvement in that area, however, with retrograde thrombosis. Three Express 2 stents (3.5 x 15 mm, 4.0 x 16 mm, and 4.0 x 12 mm) were deployed at 16 atmospheres across the lesion in the proximal LAD with an excellent end result and normal flow in the vessel (Figure 3). The patient was placed on an intraaortic balloon pump (IABP) for hemodynamic support. Intravenous heparin, eptifibatide and nitroglycerin were continued and she was transferred to the coronary care unit. Her cardiac enzymes after heart catheterization reached a peak of 7501 U/L (reference range 0–145 U/L), with CKMB > 500 ng/mL (reference range 0.0–4.9 ng/mL), and troponin T > 25 ng/mL (reference range 0.00–0.10 ng/mL). In the next few days she was started on a small dose of aspirin, which she tolerated well in spite of reported allergy. The intravenous medications and IABP were discontinued on the third day of hospitalization. The patient was started on oral medications, which included aspirin, clopidogrel, ramipril, metoprolol and simvastatin. Echocardiography was performed before hospital discharge and revealed hypokinesis of the lateral wall and akinesis of a large portion of the anterior wall, apex, and septum. The ejection fraction was 35%. Her hospital course was uneventful and she was discharged home on day eight. In subsequent follow-up during the past one year the patient has had no recurrent chest pain or other cardiac symptoms. Discussion. SCAD is an uncommon but important cause of myocardial infarction and sudden cardiac death.2 It occurs when hemorrhage or blood collects within the media of the coronary artery or between the media and external elastic lamina, which leads to compression of the true lumen of the artery.8 About 150 cases have been reported in the literature.2–5 In most reported cases the diagnosis was established at autopsy. Healthy, young women, particularly those in the peripartum period, appear to be affected more frequently. Eighty percent of SCAD occurs in women with one third of these occurring in the third trimester of pregnancy or within 3 months postpartum.4,9 The incidence of myocardial infarction during pregnancy and in the postpartum period ranges from 1 per 10,000 to 1 per 30,000.10–12 SCAD has been reported to occur as early as the ninth week of gestation and as late as the third postpartum month.2 Multiparity and advanced age have been reported to increase the risk of SCAD.2 The average age at presentation is between 35 and 40 years. The LAD is more commonly involved in women, in contrast to men who commonly have right coronary artery dissection.2,13 Sudden cardiac death is the usual mode of presentation in more then 70% of patients14 and many deaths occur within 3 to 6 weeks of initial presentation.4 Nearly 50% have a second dissection in the same or another coronary artery within 2 months of the initial event.2 Patients who survive the initial event have an 80% survival rate at 30 months regardless of the treatment modality.2 The pathogenesis of SCAD remains obscure and reports in the literature suggest that there may be several pathologic mechanisms. Patients with SCAD can be divided into three major groups; those associated with pregnancy and peripartum period, those with atheroscerotic coronary artery disease, and those with coronary spasm.2 Hemodynamic factors together with arterial wall changes, lytic action of proteases released from eosinophils, and intimal tears are the main factors hypothesized to cause SCAD.2,14,15 The predilection of SCAD in women and tendency to occur during the periparum period make hormonal influences likely.14 Hormonal changes during pregnancy, especially an excess of progesterone, leads to impairment of collagen synthesis, which induces weakness of the tunica media. Additional structural abnormalities include fragmentation of reticulin fibers, loss of normal corrugation of elastic fibers, hypertrophy of smooth muscles, loosening of ground substance, and degradation of collagen in the media.2,14,15 These changes usually return to normal within 3 months following delivery.15 Hemodynamic changes during pregnancy and the postpartum period have also been suggested as etiologic factors contributing to SCAD. During pregnancy total blood volume increases by 50% and cardiac output by 40–50%. Changes in blood volume, stroke volume, and heart rate can increase myocardial oxygen demand. The physiologic anemia and decreased diastolic blood pressure occurring during pregnancy may reduce myocardial oxygen supply and contribute to the development myocardial ischemia.11 Cardiac output increases further by 50–80% during the late stage of labor. With each uterine contraction, 300–500 mL of blood enters the systemic circulation, leading to increased stroke volume and arterial pressure.2,12 Straining and shearing forces during labor and delivery may initiate intimal rupture with subsequent hemorrhage into the media of the coronary vessels causing SCAD.15,16 Hemorrhage from weakened vasa vasorum in the outer tunica media leading to compression of the lumen and subsequent dissection has been proposed as another possible mechanism leading to SCAD.17,18 In addition the rupture of a plaque or vasa vasorum in a developing atheroma may lead to intramedial hemorrhage and subsequent dissection.4,7,19 Alterations in the coagulation and fibrinolytic system also occur during pregnancy. These include decreased releasable tissue plasma activator, changes in the level of coagulation factors, and reduction in protein S, all of which increase the risk for thrombosis and myocardial infarction.11 Robinowitz postulated that SCAD may result from an accumulation of eosinophils.20 Eosinophils have been shown to have potential collagenolytic and cytotoxic activity and may play a role during labor and postpartum uterine involution.8,21 Eosinophils may provoke medial degeneration through the release of eosinophilic cytotoxic enzymes, such as major basic protein, arylosulfatase, lysophospholipase, and peroxidase.4,8,22 However, other investigators have suggested that adventitial eosinophilic inflammation is a reactive phenomenon and not a cause of SCAD.22–24 Vasculitis also has been implicated in the etiology of SCAD and eosinophilic infiltrations have been compared to the periarteritis observed in a limited variant of the Churg-Strauss syndrome (allergic granulomatosis and angitis).25 Eosinophilic infiltrations in SCAD were focal and interstitial and did not involve small veins and capillaries as it was observed in hypersensitivity vasculitis.14,21 Isolated coronary artery dissection has also been reported in Marfan’s syndrome and in type IV Ehlers-Danlos syndrome.26,27 Cystic medial necrosis of coronary arteries with focal fragmentation of elastic fibers, loss of smooth muscle cells in the media and deposition of acid mucopolysaccharides observed in patients with Marfan syndrome has been proposed as another mechanism of SCAD.19,26 Finally, relative copper deficiency causing connective tissue defects in the arterial walls of animals has been proposed as a possible mechanism of SCAD.28 In summary, no single mechanism has been implicated to fully explain the pathogenesis in SCAD. There is no definitive treatment modality for primary SCAD. Jorgensen et al. described successful medical treatment in 7 out of 10 cases.29 Medical management is similar to the treatment of acute coronary syndrome. It includes anticoagulation with heparin, the use of nitrates, aspirin, and beta-blockers. Calcium channel blockers also seem to prevent coronary vasospasm subsequent to dissection.4,30 The use of thrombolytics remains controversial. They may lyse the thrombus of the false lumen releasing the pressure effect on the true lumen. On the other hand, they may also cause propagation of the dissection and extension of an intramural hematoma.2–4,14,15,31 Coronary angioplasty and coronary artery stenting have been performed in several patients with good results.2,3,5,15,32–34 Stent implantation appears to be superior to angioplasty alone, as the artery wall is friable and stent insertion might prevent propagation of the dissection.3,35 Coronary artery bypass surgery has been recommended for patients with multivessel, left main coronary artery dissection or symptoms refractory to medical therapy.5,15,36 Koller et al. reported the successful use of immunosuppressive therapy with prednisone and cytoxan in a 35-year-old postpartum woman with 5 noncontiguous dissections. Angiographic resolution was noted at 3 months.21 This suggests that inflammation and eosinophilic infiltration may have a predominant role in the etiology of SCAD. McKechnie described a case of a pregnant woman with SCAD successfully treated with extracorporal membrane oxygenation (ECMO) and subsequent angioplasty.6 One case of postpartum multivessel coronary dissection has been treated successfully with heart transplantation.37 There has also been one report of the treatment of SCAD exclusively with a GP IIb/IIIa inhibitor alone.7 There have been no previous reports on the use of GP IIb/IIIa inhibitors in combination with stenting in the treatment of SCAD postpartum. Our case represents the first such case with this treatment modality and a successful outcome. Conclusion. SCAD is a rare but life threatening condition that affects predominantly young, healthy women particularly during pregnancy or the postpartum period. The mortality rate is extremely high and diagnosis should be considered in any young woman who presents with an acute coronary syndrome. A high level of clinical suspicion can lead to prompt diagnosis and successful management. There is no consensus regarding the treatment of SCAD. Each case should be treated according to its unique features. Conservative medical therapy, thrombolytic therapy, percutaneous coronary balloon angioplasty, intracoronary stenting and surgery have all been used successfully. To our knowledge this case represents the first case of postpartum SCAD successfully treated with a GP IIb/IIIa inhibitor and intracoronary stenting.

1. Pretty H. Dissecting aneurysm of coronary artery in a woman aged 42. Br Med J 1931;1:667. 2. Kamineni R, Sadhu A, Alpert JS. Spontaneous coronary artery dissection: Report of two cases and 50-year review of the literature. Cardiol Rev 2002;10:279–284. 3. Shaoliang C and Baoxiang D. Treatment of spontaneous coronary artery dissection: Report of two cases. Chinese Med J 2000;113:1150–1152. 4. Dhavan R, Singh G, Fesniak H. Spontaneous coronary artery dissection: The clinical spectrum. Angiology 2002;53:89–92. 5. Klutstein MW, Tzivoni D, Bitran D, et al. Treatment of spontaneous coronary artery dissection: Report of three cases. Cathet Cardiovasc Diagn 1997;40:372–376. 6. McKechnie RS, Patel D, Eitzman DT, et al. Spontaneous coronary artery dissection in a pregnant woman. Obstet Gynecol 2001;98:899–890. 7. Cheung S, Mithani V, Watson RM. Healing of spontaneous coronary artery dissection in the context of glycoprotein IIb/IIIa inhibitor therapy. A case report. Cathet Cardiovasc Intervent 2002;51:95–100. 8. Virmani R, Forman MB, Rabinowitz M, McAllister HA. Coronary artery dissections. Cardiol Clinics 1984;2:633–645. 9. DeMaio SJ, Kinsella SH, Silverman ME. Clinical course and long-term Prognosis of spontaneous coronary artery dissection. Am J Cardiol 1989;64:471–474. 10. Samuels LE, Kaufman MS, Morris RJ, Brockman SK. Postpartum coronary artery dissection: Emergency coronary artery bypass with ventricular assist device support. Coron Art Dis 1998;9:457–460. 11. Roth A and Elkayam U. Acute myocardial infarction associated with pregnancy. Ann Intern Med 1996;125:751–762. 12. Badui E and Enciso R. Acute myoardial infarction during pregnancy and puerperium review. Angiology 1996;47:739–756. 13. Sharma AD, Sreeram G, Slaughter TF. Spontaneous coronary artery dissection in healthy 24-year-old woman. J Cardiothor Vasc Anesthesia 2000;14:312–313. 14. Mohamed HA, Eshawesh A, Habib N. Spontaneous coronary artery dissection. A case report and review of the literature. Angiology 2002;53:205–211. 15. Koul AK, Hollander G, Moscovits N, et al. Coronary artery dissection during pregnancy and the postpartum period: Two case reports and review of literature. Cathet Cardiovasc Intervent 2001;52:88–94. 16. Velusamy M, Fisherkeller M, Keenan E, et al. Spontaneous coronary artery dissection in a young woman precipitated by retching. J Invas Cardiol 2002;14:198–-201. 17. Hartman JD and Eftychiadis AS. Medial smooth-muscle cell lesions and dissection of the aorta and muscular arteries. Arch Pathol Lab 1990;114:50–61. 18. Barger AC, Beeuwkes R, Lainey LL, Silverman KJ. Hypothesis: Vasa vasorum and neovascularization of human coronary arteries. N Engl J Med 1984;310:175–177. 19. Basso C, Morgani GL, Thiene G. Spontaneous coronary artery dissection: A neglected case of acute myocardial ischemia and sudden death. Heart 1996;75:451–454. 20. Robinowitz M, Virmani R, Mc Allister HA. Spontaneous coronary artery dissection and eosinophilic inflammation: A cause and effect relationship? Am J Med 1982;72:923–928. 21. Koller PT, Cliffe CM, Ridley DJ. Immunosuppressive therapy for peripartum-type spontaneous coronary artery dissection: Case report and review. Clin Cardiol 1998;21:4046. 22. Borczuk AC, van Hoeven KH, Factor SM. Review and hypothesis: The eosinophil and peripartum heart disease (myocarditis and coronary artery dissection) — Coincidence or pathogenic significance? Cardiovasc Res 1997;33:527–532. 23. Dowling GP and Buja ML. Spontaneous coronary artery dissection occurs with and without periadventitial inflammation. Arch Pathol Lab Med 1987;111:470–472. 24. Siegel RJ and Koponen M. Spontaneous coronary artery dissection causing sudden death. Mechanical arterial failure or primary vasculitis? Arch Pathol Lab Med 1994;118:196–198. 25. Hunsaker JC, O'Connor WN, Lie JT. Spontaneous coronary arterial dissection and isolated coronary arteritis: sudden cardiac death in a patient with a limited variant of Churg-Strauss syndrome. Mayo Clin Proc 1992;67:761–766. 26. Bateman AC, Gallagher PJ, Vincenti AC. Sudden death from coronary artery dissection. J Clin Pathol 1995;48:781–784. 27. Marik PE. Coronary artery dissection after a rugby injury. A case report. S Afr Med J 1990;77:586–587. 28. Asuncion CM and Hyun J. Dissecting intramural hematoma of the coronary artery in pregnancy and the puerperium. Obstet Gynecol 1972;40:202–210. 29. Jorgersen MB, Aharonian V, Mansukhani P, Mahrer PR. Spontaneous coronary artery dissection: A cluster of cases with this rare finding. Am Heart J 1994;127:1382–1387. 30. Longheval G, Badot V, Cosyns B, Najioullah S. Spontaneou coronary artery dissection: Favorable outcome illustrated by angiographic data. Clin Cardiol 1999;22:374–375. 31. Elming H and Kober Lars. Spontaneous coronary artery dissection. Case report and literature review. Scand Cardiovasc J 1999;33:175–179. 32. Hanratty CG, McKeown PP, O'Keeffe BD. Coronary stenting in the setting of spontaneous coronary artery dissection. Internatl J Cardiol 1998;67:197–199. 33. Leclerc KM, Mascette AM., Schachter DT. Spontaneous coronary artery dissection in a young woman treated with extensive coronary stenting. J Invas Cardiol 1999;11:237–241. 34. Hong MK, Satler LF, Mintz GS, et al. Treatment of spontaneous coronary artery dissection with intacoronary stenting. Am Heart J 1996;132:200–202. 35. Rensing BJ, Kofflard M, van den Brand MJ, Foley DP. Spontaneous coronary artery dissection of all three coronary arteries in 33-week pregnant woman. Cathet Cardiovasc Intervent 1999;48:207–210. 36. Yoshida K, Mori S, Tomari S. et al. Coronary artery bypass grafting for spontaneous coronary artery dissection: A case report and review of the literature. Ann Thorac Cardiovasc Surg 2000;6:57–60. 37. Mather PJ, Hansen CL, Goldman B, et al. Postpartum multivessel coronary dissection. J Heart Lung Transplant 1994;13:533–537.