A young patient presents with a systolic murmur at the apex. The murmur increases on both handgrip and Valsalva maneuver. Which of the following conditions is most likely?

Handgrip and Valsalva maneuver may increase the intensity of the murmur of MVP. Whenever a murmur increases with Valsalva, think HOCM and MVP. Valsalva decreases ventricular filling and leads to a narrower HOCM outlet. So, HOCM murmur becomes louder. Valsalva also allows more laxity in the chordae tendinae due to the less ventricular filling. This allows the mitral valve prolapsed and its murmur to become more prominent. In a case of aoic stenosis, when the Valsalva is performed, there is less volume in ventricle to be ejected. Hence the flow across the AS is less. So it softens. When the Valsalva is performed in a case of MR, backflow in MR ( without MVP ) is less. So it softens. Ref: Harrison; 20th edition