**Introduction/Hypothesis:**
A 59-year-old female with a past medical history of bicuspid aortic valve with severe aortic stenosis and moderate-severe regurgitation status post surgical aortic valve replacement (SAVR) with a 21 mm Tophat mechanical valve and mitral valve annuloplasty on 5/11/21 presents to the valve clinic with rapidly progressive shortness of breath, dyspnea on exertion, and recurrent heart failure admissions. She also mentioned that she has had issues with scarring in the past and would develop "big scars" after cuts or procedures. On physical examination, she was noted to have a harsh 3/6 systolic ejection murmur in the right sternal border as well as a 1/4 diastolic rumble at the apex. She had 1+ pitting of the lower extremities bilaterally and bibasilar lung crackles. Laboratory evaluation revealed a mild anemia with a hemoglobin of 9.8 g/dL (normal 11.2-15.5 g/dL) and elevated NT-proBNP of 1635 pg/mL (normal < 226 pg/mL). Given these findings, our suspicion was that she had valvular dysfunction that needed further workup.

**Methods**
After thoughtful review of her presenting symptoms, physical examination, and laboratory values, we decided to proceed with a multi-modal imaging approach to further evaluate her condition. We proceeded with a chest x-ray (CXR), transthoracic echocardiogram (TTE), transesophageal echocardiogram (TEE), and a computed tomography (CT) cardiac angiogram.

**Results**
CXR revealed increased pulmonary vascularity, mitral annuloplasty band, and aortic valve prosthesis. TTE was somewhat limited due to image quality but showed a normal left ventricular size and normal bi-ventricular function. The TEE showed that there was thickening around the mechanical AVR prosthetic leaflets. The prosthetic aortic valve gradient was 71 mmHg, suggestive of critical aortic stenosis. There was also thickening of the basal anteroseptum with associated systolic anterior motion of the mitral valve. The mitral valve also appeared thickened with a mean inflow gradient of 8 mmHg (heart rate 82 BPM), suggestive of significant mitral stenosis. Please refer to Figure 1. The subsequent cardiac CT showed a distinct subaortic membrane in the left ventricular outflow tract immediately below the AVR prosthesis. The mechanical leaflets appeared to be moving well without restriction. There was no thrombus on the prosthetic valve. There was also a dense pannus/scarring on the mitral annuloplasty band resulting in limited mitral valve area. Please refer to Figure 2. Given the findings of discreet subaortic membrane resulting in severe stenosis as well as dense pannus of the mitral annuloplasty ring causing significant symptoms, patient was sent for repeat cardiovascular surgery. Intraoperative findings showed that her prior AVR sutures were dehisced (with only 2 remaining in place) and the AVR was being held in place by essentially fibrotic scar tissue. There was also dense fibrotic tissue in the LVOT. Finally, there was a large tumor like fibrotic mass that was attached to the posterior mitral annulus around the mitral annuloplasty band. Infact, the mitral annuloplasty band was found to be completely dehisced from the annulus. She underwent redo sternotomy with a Bentall aortic root replacement and mechanical aortic valve replacement with a 21 mm On-X valve conduit, mitral valve replacement (MVR) with a 23 mm On-X mechanical valve, and septal myectomy. Pathologic specimens from the operation showed dense fibrotic tissue with calcification, hemosiderin deposition, and acute on chronic inflammation without micro-organisms.

**Conclusion**
Here we present a unique case of an systemic aggressive scarring process leading to the formation of discrete sub-aortic membrane and pannus formation on a mitral annuloplasty band that required the use of multimodal cardiac imaging to clinch the diagnosis. The patient is currently doing well after her redo AVR and MVR with plans to follow up closely over the next few years to monitor for recurrence.



Valvular Keloids? A case of aggressive scarring leading to severe multivalvular obstruction