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case_images: Transthoracic echocardiogram. A calcified tumour detected at the anterior mitral leaflet and left ventricular outflow tract obstruction in the apical three-chamber view.
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case_images: Transthoracic echocardiography (TTE) detected a calcified tumour of the intervalvular fibrosa (IVF) of the anterior mitral leaflet (AML), leading to left ventricular outflow tract (LVOT) obstruction (LVOTO). (Figure 1, Supplementary material online, Video S1) A follow-up TTE revealed normal left ventricular function with an ejection fraction of 60%, mitral stenosis (MS) due to a calcified tumour, and MAC (calcified or non-rheumatic MS).
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case_images: Cardiac computed tomography displays a calcified mass. The mass seems to extend to the posterior of the left atrium and non-coronary cusp.
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case_images: CT confirmed that the calcified tumour was expanding during IVF, and the calcification seemed to extend to the non-coronary cusp (NCC) (Figure 2, Supplementary material online, Video S2).
case_images: In pressure measurement with a catheter, the mean pressure gradient of the left ventricular outflow tract with valsalva provocation is 31 mmHg, and the maximum pressure gradient is 51 mmHg. We tested nitrogen provocation using nitro-glycerine (100 microg), displaying 75 mmHg in the maximum pressure gradient of the left ventricular outflow tract. When the Brockenbrough phenomenon was observed during catheter examination, the maximum pressure gradient of the left ventricular outflow tract was rising to 145 mmHg.
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case_images: Post-operative TTE showed that the CAT had been successfully removed, and LVOTO was improved with a significantly better LVOT PG during the Valsalva manoeuvre compared to preoperative levels (Figure 5, Supplementary material online, Video S3).
case_images: (A) Illustration of incisional view. The transseptal atriotomy and aortotomy were performed to across the left and non-coronary commissure into the anterior mitral valve leaflet with opening the IVF. (B) The gross findings of aortic valve cusps during surgery display a calcified amorphous tumour and septal myocardium protruding into the left ventricular outflow tract. RCS, right coronary sinus; VS, ventricular septum; NCS, non-coronary sinus; MS, membranous septum; CAT, calcified amorphous tumour; LA, left atrium; MV, mitral valve; PML, post-mitral leaflet; Ao, aorta, (C) CAT specimen after resection. CAT was covered with fibrous tissue. (D) Histopathology image of CAT. Most of the unstructured deposits are calcification. Calcium deposits are present in the cavity along with eosinophilic deposits. Macrophage infiltration was observed in the background.
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case_images: The Brockenbrough phenomenon was observed during catheter examination, and the maximum PG of the LVOT increased to 145 mmHg. (Figure 4) The peptide level increased to 915 pg/mL. Under conventional cardiopulmonary bypass and aortic clamping, we performed a transseptal atriotomy and extended the aortotomy by opening the IVF (Figure 4A). The tumour surface was smooth and covered the endocardium (Figure 4B). On gross examination, the tumour was surrounded by fibrous tissues, firm with calcification and debris, and measured 1.4 x 0.8 cm (Figure 4C). Macrophage infiltration was observed in the background (Figure 4D).
case_images: PMC11804242_03
case_images: In pressure measurement with a catheter, the mean pressure gradient of the left ventricular outflow tract with valsalva provocation is 31 mmHg, and the maximum pressure gradient is 51 mmHg. We tested nitrogen provocation using nitro-glycerine (100 microg), displaying 75 mmHg in the maximum pressure gradient of the left ventricular outflow tract. When the Brockenbrough phenomenon was observed during catheter examination, the maximum pressure gradient of the left ventricular outflow tract was rising to 145 mmHg.
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case_images: Post-operative TTE showed that the CAT had been successfully removed, and LVOTO was improved with a significantly better LVOT PG during the Valsalva manoeuvre compared to preoperative levels (Figure 5, Supplementary material online, Video S3).
case_images: Transthoracic echocardiogram. Preoperatively, the maximum pressure gradient in the left ventricular outflow tract was 85 mmHg with the valsalva manoeuvre, but it improved to 15 mmHg post-operatively.
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case_images: Post-operative TTE showed that the CAT had been successfully removed, and LVOTO was improved with a significantly better LVOT PG during the Valsalva manoeuvre compared to preoperative levels (Figure 5, Supplementary material online, Video S3).