"Lambda-wave" ST-elevation is associated with severe prognosis in stress (takotsubo) cardiomyopathy

Persistent ST-segment elevation in acute coronary syndrome is associated with both short and long-term complications. By contrast, there is limited information about ST-elevation and its evolution during takotsubo (stress) cardiomyopathy (TTC).

To evaluate whether persistent downsloping ST-elevation in the early stages of TTC might correlate with short and long-term clinical events.

One-hundred fifty-eight consecutive subjects with TTC were prospectively enrolled and assessed by electrocardiogram. Patients were classified in two groups according to the presence of downsloping ST-elevation ≥5 mm lasting at least 24 hr ("lambda-wave" ST-elevation group vs. without downsloping ST-elevation) in at least one/two contiguous leads.

Five (3.2%) patients, all female with a mean left ventricular ejection fraction 32 ± 5%, were included in the lambda-wave ST-elevation group. These patients were characterized by a higher prevalence of physical stressor (100% vs. 49%, p = 0.04) and higher admission and peak levels of troponin-I levels during hospitalization. Peak of ST-elevation in the lambda-wave ST-elevation group was reached 6 hr after admission and gradually decreased after 24 hr. In-hospital complications were observed in all the patients presenting lambda ST-elevation (100% vs. 23%, p = 0.03, OR: 29.1, p = 0.04); one patient presented endoventricular thrombosis and two died of cardiogenic shock. At long-term follow-up (mean 443 days), adverse events were observed in 80% of patients with lambda-wave ST-elevation (RR of adverse events at follow-up 32, p < 0.01).

Persistent downsloping lambda-wave ST-elevation during the acute phase of stress cardiomyopathy may be associated with a higher risk of adverse events at short and long-term follow-up.