**11. Complications**

Takotsubo syndrome has been associated with a growing list of complications of varied severity, contributing to its mortality rate. Almost 52% of all patients have been reported to develop some form of complication in course of this disease [62, 63]. These include acute heart failure, left ventricular outflow tract obstruction, cardiogenic shock, arrhythmias, thrombus formation, pericardial effusion, right ventricular involvement and ventricular wall rupture.

Acute heart failure develops in almost 12–45% of all patients with TTS and, in some patients, it is exacerbated by mitral regurgitation and/or left ventricular tract obstruction. Patients could have significantly elevated LVOT gradients (20–140 mmHg), and those with values greater than 40 mmHg are predisposed to develop hypotension and cardiogenic shock. It has been demonstrated that the use of inotropic drugs exacerbates this LVOT obstruction, while beta-blockers decrease it. Around 4–20% of all TTS patients show symptoms of cardiogenic shock, while almost 9% of them document ventricular arrhythmias during the acute phase. Thrombi develop generally 2–5 days after the index event and are known to resolve after 2 weeks of therapeutic anticoagulation (treatment regimen of at least 3 months). There are also instances of patients presenting with a biventricular involvement, which has been associated with a poorer prognosis and a higher frequency of heart failure [10].
