Nicholas Suraci1, Howard Goldman1, Diego Baruqui2, Orlando Santana3 1 Department of Anesthesia, Mount Sinai Medical Center, Miami Beach, Florida, USA 2 Department of Internal Medicine, Mount Sinai Medical Center, Miami Beach, Florida, USA 3 Echocardiography Laboratory, Columbia University Division of Cardiology at the Mount Sinai Heart Institute, Miami Beach, Florida, USA
An asymptomatic 30-year-old male was referred for a transthoracic echocardiogram because of a systolic murmur that was noted on a pre-employment physical exam. Transthoracic imaging demonstrated a single papillary muscle from which the chordae of both mitral valve leaflets were attached. The mitral valve was seen to have a parachute-like configuration. Given the benign nature of the presentation, the patient did not seek further investigation.
A 30-year-old obese male was referred for an echocardiogram because of a murmur that was noted on a pre-employment physical exam. Upon physical exam, he was noted to have a grade II/I holosystolic murmur noted in the left lower sternal border, which radiated into the left axilla. There were no other significant findings on the physical examination. The patient was completely asymptomatic and exercised on a regular basis.
A two-dimensional transthoracic echocardiography performed demonstrated only a single papillary muscle from which the chordae of both the mitral valve leaflets were attached. In the apical four-chamber view, the mitral valve had a parachute-like configuration [[Figure 1] and Video 1]. No mitral stenosis was noted, but the patient did have moderate mitral regurgitation. No other cardiac lesions were present. Given that the patient was asymptomatic, he chose to pursue no further imaging or intervention.
Figure 1: Two-dimensional transthoracic echocardiography apical four-chamber view. Arrow demonstrates a “pear-shaped” parachute mitral valve. LA = Left atrium, RA = Right atrium, LV = Left ventricle, RV = Right ventricle
A parachute mitral valve abnormality is more common in males and is characterized by all chordae tendinae inserting into a single papillary muscle of muscle group resulting in mitral inflow obstruction. Parachute mitral valve is said to have a characteristic “pear” shape in the apical four-chamber view. In adults, and because opening of the mitral valve is limited, it is highly associated with mitral stenosis, with mitral regurgitation occurring less commonly., This disorder is reported as an isolated lesion in 55.5' of cases and, in 44.4' of cases, it is reported with other obstructive left-sided heart lesions such as supravalvular mitral ring, subaortic stenosis, and coarctation of the aorta, known as Shone's complex, as well as, aortic valve stenosis, atrial septal defects, and hypoplastic left heart. It occurs when the development of the anterolateral and posteromedial papillary muscles is disrupted between the fifth and nineteenth week of gestation, thereby forcing the embryonic predecessors of the papillary muscles to condense into a single muscle. The outcomes of patients with a parachute mitral valve are dependent on the spectrum of associated cardiac lesions, with the degree of mitral valve obstruction remaining stable; the majority will not require valvotomy. Surgical treatment consists of either choral fenestration or papillary muscle splitting, with or without commissurotomy.