Select a Community
Are you sure you want to trigger topic in your Anconeus AI algorithm?
Decreased murmur in hypertrophic obstructive cardiomyopathy
71%
5/7
Decreased murmur in mitral stenosis
14%
1/7
Increased murmur in aortic stenosis
Increased murmur in hypertrophic obstructive cardiomyopathy
0%
0/7
Increased murmur in mitral stenosis
Select Answer to see Preferred Response
This patient is presenting with syncope upon exertion and a murmur that suggests a diagnosis of hypertrophic obstructive cardiomyopathy (HOCM). The murmur of HOCM is reduced with squatting.HOCM classically presents with syncope upon exertion in a young patient. Though sudden death is a possible complication, this is a less common presentation than syncope. When a patient squats, preload and afterload are increased. The increase in preload increases the volume of blood in the heart. Similarly, the increase in afterload decreases the ejection fraction thus increasing the volume of blood in the heart. In HOCM, the increase in the volume of the cardiac chambers decreases outflow obstruction thus reducing the murmur. Treatment is with beta-blockers, lifestyle changes, and possible defibrillator implantation.Naik and Shah review the evidence regarding heart murmurs in teenagers. They discuss how multiple benign and pathologic etiologies may all be responsible for a new onset murmur. They recommend making an accurate diagnosis in order to reduce morbidity.Incorrect Answers:Answers 2 & 5: Increased/decreased murmurs in mitral stenosis are the incorrect diagnosis for this patient. Mitral stenosis can occur in the setting of rheumatic fever (possible with this patient's history of Streptococcal pharyngitis) and presents with a mid-diastolic rumbling heard best at the cardiac apex. Treatment is with valve replacement.Answer 3: Increased murmur in aortic stenosis does describe the change in the murmur that would occur with squatting. However, this patient's age, and classic presentation of syncope in a young athlete is more suggestive of HOCM rather than aortic stenosis. Treatment is with valvuloplasty or valve replacement.Answer 4: Increased murmur in hypertrophic obstructive cardiomyopathy (HOCM) does not describe the changes that would occur when cardiac chamber volume increases (such as during squatting). This finding would be heard if the patient were asked to stand, or if afterload were decreased (such as administering an ACE inhibitor).Bullet Summary:Squatting increases preload and afterload and reduces the murmur heard in HOCM.
3.9
(7)
Please Login to add comment