Imaging findings

Stress cardiomyopathy, also known as Takotsubo cardiomyopathy or apical ballooning syndrome, is a condition characterized by chest pain simulating acute coronary syndrome. There are severe ventricular wall motion abnormalities with a notable absence of obstructive coronary artery disease. Stress cardiomyopathy is a transient phenomenon, thought to be related to an acute increase in sympathetic activity due to severe physical or emotional stress, and the vast majority of patients will have complete normalization of cardiac abnormalities at follow-up. Ventricular “ballooning” is the hallmark of the disease, characterized by akinesis or dyskinesis of ventricular walls during systole that is not confined to a single vascular territory (Figure 12.1). The ballooning occurs in the apex in more than 80% of patients. Mid-ventricular, biventricular, and basilar ballooning patterns can also be seen, although much less frequently. On cardiac MRI, transmural myocardial edema involving dyskinetic myocardial segments is present in the majority of patients. However, late gadolinium enhancement (LGE) is mostly absent. The prevalence of LGE reported in the literature ranges from 9–44% of patients, and this variability is thought to be related to interstudy differences in the threshold used to define late gadolinium enhancement. In the largest study to date evaluating 239 patients, when a standard threshold of 5 SD above remote myocardium was used to define LGE not a single patient had detectable LGE. When present, LGE may be patchy or transmural and will not conform to a vascular territory. When evaluated by cardiac CT, multiphase retrospectively-gated images will demonstrate the typical ventricular ballooning pattern and coronary arteries will be free from significant plaque (Figure 12.2).

Importance

The diagnosis of stress cardiomyopathy is challenging given its close resemblance to acute coronary syndrome, particularly since patients with stress cardiomyopathy may have EKG changes and elevated cardiac enzymes in addition to ventricular dysfunction. However, treatment and prognosis are very different between the two entities.