Manifestation of latent left ventricular outflow tract obstruction caused by acute myocardial infarction: An important complication of acute myocardial infarction

Case report: A patient with transient sigmoid septum in takotsubo syndrome with left ventricular outflow tract obstruction

Left ventricular outflow tract obstruction is now recognized as a common complication of takotsubo syndrome, resulting in more serious acute and long-term outcomes. We describe a case of takotsubo syndrome where a transient sigmoid septum produced left ventricular outflow obstruction and explore the mechanisms leading to this occurring. This phenomenon has not been previously described. <Learning objective: Left ventricular outflow tract (LVOT) obstruction is a complication of takotsubo syndrome. A sigmoid septum is a risk factor for LVOT obstruction occurring. This case highlights that a sigmoid septum can be transient and may be secondary to surge in catecholamines and inflammatory markers.>.

Unstable angina complicated with dynamic left ventricular outflow tract obstruction

Left ventricular outflow tract obstruction (LVOTO) complicated with unstable angina (uAP) has not been described widely, but patients with these two conditions have several problems. Differentiation of the two conditions is also often difficult because the chest symptoms are similar. Moreover, nitrates are commonly used for ischemic heart disease, but have the effect of worsening LVOTO. We experienced three cases of dynamic LVOTO with a sigmoid-shaped septum, and without typical hypertrophic obstructive cardiomyopathy, that were complicated with uAP. In all cases, LVOTO was improved after initial percutaneous coronary intervention (PCI) for the left anterior descending artery lesion. Next, a dobutamine stress test was performed and LVOTO was provoked again in two cases, but not in a case with small acute myocardial infarction of the basal septum during PCI. All cases remained asymptomatic with beta-blocker therapy. Therefore, PCI and beta-blocker administration for LVOTO with uAP resulted in favorable clinical courses in all three cases. These outcomes suggest that revascularization including PCI should have priority in the therapeutic strategy for a case of acute coronary syndrome with LVOTO.

Dynamic left ventricular outflow tract obstruction in a patient with acute coronary syndrome and without the apical akinesia: Potential alternative mechanisms causing a dynamic left ventricular outflow tract obstruction other than a compensatory basal hyperkinesis

The mechanism for dynamic left ventricular outflow tract obstruction (LVOTO) after acute coronary syndromes (ACS) is thought to be apical infarction with compensatory hyperkinesia of the residual normally perfused basal segments of the myocardium. However, herein, we report a patient with ACS and dynamic LVOTO (peak gradient of 250 mm Hg at rest) that could not be secondary to apical akinesia. We propose a potential alternative mechanism leading to dynamic LVOTO in ACS, namely, the interplay between sigmoid septum, basal hyperkinesis, and outflow tract narrowing induced by afterload reduction due to acute myocardial ischemia itself.

Dynamic left ventricular outflow tract obstruction complicated with takotsubo cardiomyopathy: The acute phase of takotsubo cardiomyopathy manifests latent left ventricular outflow tract obstruction

Dynamic left ventricular (LV) outflow tract (LVOT) obstruction is sometimes complicated with takotsubo cardiomyopathy (TC). The present case involves a 70-year-old woman with chest discomfort. Seven years earlier, transthoracic echocardiography revealed LVOT obstruction due to a sigmoid-shaped septum. She underwent urgent cardiac catheterization for suspected acute coronary syndrome. She was diagnosed as having TC with LVOT obstruction. After undergoing conservative treatment, her LV function normalized and the LVOT obstruction resolved. After the LV wall motion normalized, administering an intravenous infusion of dobutamine again provoked LVOT obstruction. In this situation, the presence of TC manifested latent LVOT obstruction. <Learning objective: Although dynamic left ventricular outflow tract (LVOT) obstruction is the important compication of takotsubo cardiomyopaty (TC), the mechanism of LVOT obstruction remains unclear. This case had latent LVOT obstruction due to sigmoid-shaped septum, and LVOT obstruction might be manifested in the acute phase of TC. This phenomenon has potential for mechanism of LVOT obstruction complicated with TC.>.

Manifestation of Latent Left Ventricular Outflow Tract Obstruction in the Acute Phase of Takotsubo Cardiomyopathy

Objective Left ventricular outflow tract (LVOT) obstruction is a complication in 15-25% of patients with Takotsubo cardiomyopathy and sometimes leads to catastrophic outcomes, such as cardiogenic shock or cardiac rupture. However, the underlying mechanisms have not been clarified. Methods and Results We experienced 22 cases of Takotsubo cardiomyopathy during 3 years, and 4 of these 22 cases were complicated with LVOT obstruction in the acute phase (mean age 79±5 years, 1 man, 21 women). The LVOT pressure gradient in the acute phase was 100±17 mmHg. Transthoracic echocardiogram (TTE) revealed left ventricular hypertrophy (LVH) in one case and sigmoid-shaped septum without LVH in three cases. The complete resolution of the LVOT obstruction was achieved in a few days with normalization of the left ventricular wall motion following administration of beta-blockers. A dobutamine provocation test after normalization of the left ventricular wall motion reproduced the LVOT obstruction in all cases and revealed the presence of latent LVOT obstruction. Conclusion The manifestation of latent LVOT obstruction in the acute phase of Takotsubo cardiomyopathy is one potential reason for the complication of LVOT obstruction with Takotsubo cardiomyopathy.