P711 Rapid and severe decompensation of obstructive hypertrophic cardiomyopathy
Authors: Pascal A M , Scarlatescu A , Alexandrescu A , Dorobantu M 
Published: January 2020

Abstract

INTRODUCTION
Obstructive hypertrophic cardiomyopathy (HCM) is a complex disease which affects not only the ventricular walls, but frequently the mitral apparatus and the aortic valve are also involved. Many patients adapt over time tolerating different grades of pulmonary hypertension and heart failure (HF). However, complications such as severe valvulopathies, can often end up in difficult to manage situations.

CASE REPORT
A 46 years old woman was admitted for chest pain and heavy breathing. She was diagnosed with HCM at the age of 28, but her clinical course was stable since then. Her clinical examination, EKG and blood test showed no relevant modifications.

Transthoracic and transesophageal echocardiography
Important left ventricular outflow tract (LVOT) obstruction. Maximum wall thickness-23 mm. Severe subvalvular aortic stenosis: classical dynamic stenosis in HCM because of SAM, and a possible semicircular subvalvular aortic membrane. Severe mitral regurgitation due to ruptured chordae attached to the P2 scallop. Severe pulmonary hypertension. Pericardial effusion-maximum 16 mm. The cardiac catheterization noticed a cardiac output of 1.78 l/min.
The association of the severe mitral regurgitation to the LVOT obstruction results in a very low cardic output leading to acute heart failure. The pacient had surgical indication for the ruptured chordae. The heart team decided that the risks exceeded the benefits. The following few months were marked by multiple episodes of HF. After 6 months she died of cardiac arrest.

DISCUSSIONS
HCM is a genetic disease which associates numerous echocardiographic particularities. One of them is the elongation of the anterior mitral cusp and a greater laxity of the entire mitral valve, predisposing to mechanical complications. The particularity of this case is that although the patient adapted very well over time having obstructive HCM and secondary severe pulmonary hypertension, a complication of the mitral valve (ruptured chordae) resulted in a very low cardiac output and rapid decompensation.
The patient also associated pericardial effusion probabily secondary to severe pulmonary hypertension. Although the effusion was not large, in such cases with very low cardiac output, an impairment of the left ventricle’s diastolic function could be an important factor.
The management of a patient with obstructive HCM that associates a severe valvulopathy is always challenging. The use of diuretics has to be carefully managed, as this medication can be harmful by lowering the cardiac output even more. On the other hand, the diuretic’s dose has to be efficient on improving the symptoms.

CONCLUSIONS
Patients with obstructive HCM can develop a great variety of complications. In this case, the hyperlaxity of the mitral apparatus which accompanies this affliction led to a ruptured chordae and secondary severe mitral regurgitation. The valvulopathy severely decompensated a known cardiomyopathy resulting in acute HF.
Abstract P711 Figure. HCM