• Echocardiography is recommended in all patients undergoing medical and invasive treatment: Intraoperative TOE is mandatory during surgery and intracoronary MCE is mandatory during ASA.
• When gradient reduction therapy is considered (surgical myectomy or ASA), CMR provides detailed anatomical and pathophysiological information on the mechanism of LVOT obstruction and/or of MR, with impact on the choice of procedure (surgery vs. ASA) and on the type of surgery (valve replacement vs. repair of leaflets, chordae, PMs).
• CT can be used to evaluate the anatomical distribution of the septal arteries before ASA. CT is an alternative when echocardiographic images are inadequate and CMR is contraindicated.
• Routine nuclear imaging for the assessment of therapeutic procedures (non-invasive and invasive) is not recommended in patients with HCM. It may be performed when there are technical limitations, non-availability or contraindications for echocardiography, CMR or CCT.