Postpartum coronary vasospasm with literature review

Acute Myocardial Infarction in Pregnancy

Cardiovascular disease, and particularly ischemic heart disease, is a leading cause of maternal morbidity and mortality in high-income countries. The incidence of acute myocardial infarction (AMI) has been rising over the past two decades due to increasing maternal age and a higher prevalence of cardiovascular risk factors in the pregnant population. Causes of AMI in pregnancy are diverse and may require specific considerations for their diagnosis and management. In this narrative review, we provide an overview of physiologic changes, risk factors, and etiologies leading to AMI in pregnancy, as well as diagnostic tools, reperfusion strategies, and pharmacological treatments for this complex population. In addition, we outline considerations for labor and delivery planning and long-term follow-up of patients with AMI in pregnancy.

Pathobiology and evolving therapies of coronary artery vasospasm

Coronary artery vasospasm is a known cause of chest pain and requires a high level of clinical suspicion for diagnosis. It also remains in the differential diagnosis for patients presenting with type 2 myocardial infarction. There are few randomized controlled trials for guideline-based prevention and treatment for coronary artery vasospasm. In this article, we review updated concepts in coronary artery vasospasm. Specifically, our aim is to provide current evidence of pathophysiology, identify the risk factors, propose a diagnostic algorithm, review available evidence of evolving therapies, and identify patients who would benefit from automatic implantable cardioverter defibrillators.

Fitting a Square Peg in a Round Hole: A Simple Case of Chest Pain

A 39-year-old female presents to the emergency department with chest pain and shortness of breath. Her electrocardiogram suggests ST-elevation myocardial infarction, but she has no atherosclerotic risk factors. She is gravida 4, para 4, and four weeks postpartum from uncomplicated vaginal delivery. She is diaphoretic and anxious, but otherwise her exam is unremarkable. Cardiac enzymes are markedly elevated and point-of-care echocardiogram shows inferolateral hypokinesis and ejection fraction of 50%. In this clinicopathological case, we explore a classically underappreciated cause of acute coronary syndrome in healthy young women.

Coronary artery vasospasm induced acute myocardial infarction in pregnancy: a new case and systematic review of the literature

Background

Acute myocardial infarction (AMI) in pregnancy is a rare event and of the causes, coronary artery vasospasm (CAV) is considered even more uncommon.

Purpose

We present a new case report of a woman at 32 weeks of pregnancy with an AMI from CAV with a normal coronary angiogram. We performed a systematic review of similar cases of spontaneous AMI related to CAV to better understand its characteristics and management. AMI was defined as elevated cardiac enzymes (troponin or CKMB) with chest pain and/or electrocardiogram (EKG) changes consistent with ischemia.

Methods

We use the terms “acute myocardial infarction”, “myocardial infarction”, “coronary artery vasospasm” and “pregnancy” for our PubMed review. We also evaluated all references in identified manuscripts. Six cases of AMI in pregnancy due to CAV have been reported as of November 2016, including ours.

Results and conclusion

Six cases of AMI due to CAV during pregnancy or postpartum are reported in the literature, including ours. Patients experiencing this condition tend to be of advanced maternal age, multigravida and in their third trimester or postpartum. Successful management with a combination of long acting nitrates and/or calcium channel blockers achieved symptomatic control in all published cases. Obstetric outcomes were mostly normal, with the majority experiencing uncomplicated deliveries at term.

Responsiveness of Coronary Arteries to Nitroglycerin under Hypoxia: The Importance of the Endothelium

<b><i>Background/Aims:</i></b> Nitroglycerin is widely used as a coronary vasodilator in the treatment of ischemic heart diseases. This study investigated the influence of hypoxia on nitroglycerin-induced relaxation in endothelium-intact and -denuded rabbit, monkey, and porcine coronary arteries. <b><i>Methods:</i></b> Helically cut strips of coronary arteries were suspended in organ chambers, and isometric tension was recorded. <b><i>Results:</i></b> Nitroglycerin concentration dependently relaxed endothelium-intact rabbit coronary arteries, which were not different under normoxic and hypoxic conditions. On the other hand, nitroglycerin-induced relaxation of endothelium-denuded arteries was significantly attenuated by hypoxia. Similarly, the relaxant response of endothelium-intact monkey coronary arteries to nitroglycerin was not affected by hypoxia, whereas that of endothelium-denuded arteries was impaired. As is the case with rabbit and monkey coronary arteries, exposure to hypoxia resulted in impaired relaxation by nitroglycerin in endothelium-denuded but not endothelium-intact porcine coronary arteries. <b><i>Conclusion:</i></b> These findings suggest that coronary endothelium plays a pivotal role in preventing the hypoxia-induced impairment of nitroglycerin responsiveness, regardless of the animal species.