Fatigue and dyspnea that reduce exercise performance are common symptoms in patients with hypertrophic cardiomyopathy. Since the cause of this functional limitation has not yet been described, this study aims to evaluate the cardiopulmonary parameters measured at cardiopulmonary exercise test in combination with those obtained by non-invasive measurement of cardiac output by impedance (Physioflow) and echocardiography. These results will help to better define the mechanisms underlying limitation in these patients, also in relation to the degree of LVOT obstruction.

The aim of the present study is to assess the cardiopulmonary response to exercise in patients with hypertrophic cardiomyopathy, based on the degree of LVOT obstruction, by adding non-invasive measurement of cardiac output by Physioflow and echocardiographic parameters to the cardiopulmonary exercise test parameters associated with stroke volume and cardiac output (ie. VO2/WR, O2pulse) Consecutive patients with a previous diagnosis of hypertrophic cardiomyopathy on optimised medical therapy will be enrolled to perform a cardiopulmonary exercise test with simultaneous measurement of cardiac output and an exercise echocardiogram for clinical routine.

Inclusion Criteria:

• hypertrophic cardiomyopathy diagnosis

Exclusion Criteria:

• use of long-term oxygen therapy;
• presence of comorbidities affecting the ability to perform cardiopulmonary exercise test or interfering with exercise performance;
• concomitant at least moderate chronic obstructive pulmonary disease

Consecutive patients with a previous diagnosis of hypertrophic cardiomyopathy in optimised medical therapy will be enrolled