Description

• Transient stress cardiomyopathy (TSC) is a unique cause of reversible left ventricle (LV) dysfunction with a presentation indistinguishable from the acute coronary syndromes (ACS), particularly ST-segment elevation myocardial infarction (STEMI) (1).
• Typically, the patient is a postmenopausal woman who presents with acute chest pain, dyspnea, or syncope and an identifiable “trigger” (i.e., an acute emotional or physiologic stressor).
• First reported by authors from Japan as takotsubo cardiomyopathy, the Japanese word for octopus trap, due to the characteristic shape of the LV at the end of systole. It has been described under numerous names in the literature including “broken heart syndrome,” “stress cardiomyopathy,” and “apical ballooning syndrome.”
• Presenting clinical features include the following:
  • Chest pain/pressure, dyspnea and/or syncope
  • ECG changes, including ST-segment elevations or diffuse T-wave inversions
  • Mild elevation in cardiac biomarkers (creatine kinase [CK], troponin)
  • Transient wall motion abnormalities that may involve the base, midportion, and/or lateral walls of the LV
  • The apex of the right ventricle (RV) may be affected in up to 25% of cases (1)[B].
• Clinical features may vary on a case-by-case basis, and formal diagnostic criteria have not been established.
• Authors from the Mayo Clinic have proposed that three of the four following criteria establish the diagnosis (1)[A]:
  • Transient akinesis or dyskinesis of the LV apical and midventricular segments with regional wall motion abnormalities extending beyond a single epicardial vascular distribution
  • Absence of obstructive coronary artery disease (CAD) or angiographic evidence of acute plaque rupture
  • New ECG abnormalities, either ST-segment elevation or T-wave inversion
  • Absence of
    • Recent significant head trauma
    • Intracranial bleeding
    • Pheochromocytoma
    • Obstructive epicardial CAD
    • Myocarditis
    • Hypertrophic cardiomyopathy
• Synonym(s): takotsubo cardiomyopathy; apical ballooning syndrome; stress cardiomyopathy; broken heart syndrome; ampulla cardiomyopathy

Epidemiology

• TSC accounts for an estimated 1–3% of all and 5–6% of female patients presenting with suspected STEMI.
• In a recent prospective evaluation of patients admitted to the ICU, as many as 28% had apical ballooning, often in association with sepsis.
• Predominant sex: 82–100% of cases occur in women.
• Predominant age: Mean age of patients is 62 to 75 years.

Prevalence
2.2% of patients presenting to a referral hospital with ST-segment MIs were found to have TSC.

Etiology and Pathophysiology

• The precise pathophysiologic mechanisms of TSC are not well understood.
• There is considerable evidence that sympathetic stimulation is central to its pathogenesis. A clear emotional or physiologic triggering event precipitates the syndrome in most cases, and TSC has been associated with conditions of catecholamine excess (e.g., pheochromocytoma, central nervous system disorders) and activated specific cerebral regions (1).
• Occurs primarily in subjects with increased susceptibility of the coronary microcirculation and of cardiac myocytes to stress hormones leading to temporary left ventricular dysfunction with secondary myocardial inflammation (1)
• A perturbation in the brain–heart axis, originating in the insular cortex, may be the inciting event (2).
• Subsequent overwhelming activation of the sympathetic nervous system initiates a cascade of events, including the following:
  • Catecholamine-induced LV dysfunction: “biased agonism” of epinephrine for β₂-adrenergic receptors, located predominantly at the cardiac apex
  • Endothelial dysfunction and vasospasm
  • Cellular metabolic injury
    • Myocardial norepinephrine release
    • Calcium overload
    • Contraction band necrosis

Genetics
No genetic associations have been described to date.

Risk Factors

• Female sex
• Postmenopausal state
• Emotional stress (i.e., argument, death of family member), more common in women
• Physiologic stress (i.e., acute medical illness), more common in men
• Chronic neurologic or psychiatric disease (2)

Commonly Associated Conditions

Death from TSC is rare, and most cases resolve rapidly, within 2 to 3 days. Reported complications include:

• Left-sided heart failure
• Pulmonary edema
• Cardiogenic shock and hemodynamic compromise
• Dynamic LV outflow tract gradient complicated by hypotension
• Mitral regurgitation
• Ventricular arrhythmias
• LV thrombus formation
• LV free wall rupture
• Death (rare, 0–8%)