Echocardiographic diagnosis of rupture of mitral valve papillary muscle.

OBJECTIVE: To explore the value of echocardiography in diagnosing papillary muscle rupture (PMR) of the mitral valve, and summarize the characteristic echocardiographic features of different types.

METHODS: Echocardiograms of 13 PMR patients confirmed by surgery in Wuhan Union Hospital between January 2009 and December 2022 were retrospectively analyzed and their preoperative transthoracic echocardiography (TTE) was compared with surgical findings.

RESULTS: A total of 9020 patients underwent mitral valve repair or replacement surgery during the study period including 13 (0.14%) for PMR. Of the 13 PMRs, 8 cases were partial PMR(P-PMR), 5 cases were complete PMR(C-PMR); 3 cases were anterolateral PMR, and 10 were posteromedial PMR. The diagnostic accuracy, sensitivity, and specificity of the preoperative TTE were 99.9%, 53.8% and 99.9% respectively. Echocardiographic features of 10 patients (5C-PMR and 5 P-PMR) with detailed TTE and intraoperative transesophageal echocardiography (TEE) data included: both anterior and posterior leaflets prolapse (C-PMR 60% vs P-PMR 60%); flail leaflet (C-PMR100% vs P-PMR 40%); All C-PMRs and P-PMRs have severe, eccentric and lateral regurgitation; flail attachment (chordae tendinae and ruptured PM) at the tip of prolapsed leaflet (C-PMR100% vs P-PMR 60%); high-echo masses resembled "champagne glasses" in 100% of the C-PMR; high-echo masses resembled "lotus-seedpod" in 60% and "dumbbell-shaped" torn PM in remaining 40% of the P-PMR.

CONCLUSIONS: Different PMR subtypes have different echocardiographic characteristics. Combining TTE and TEE can accurately identify the typical features of PMR such as ipsilateral hemipetal leaflet prolapse, high-echoic mass at the tip of the leaflet, massive eccentricity and lateral regurgitation.