Mitra-clip in Transthyretin Amyloidosis Cardiomyopathy A Case Series

INTRODUCTION: Non-invasive valvular interventions have dramatically changed the management of patients with multiple complex comorbidities. Patients with cardiac amyloidosis (CA) are often considered high-risk for surgical intervention. Trans-catheter aortic valve replacement (TAVR) is tolerated in this population, however, little is known about the safety and efficacy of per-cutaneous mitral valve interventions, such as the MitraClip procedure. We present three patients with CA and mitral regurgitation (MR) who have undergone this procedure. CASES: A 75-year-old man with wild-type transthyretin cardiac amyloidosis (wtATTR), atrial fibrillation with prior ablations, a Watchman device in the left atrial appendage, resection of a malignant lung nodule presented with recurrent right pleural effusions. On exam, he had a loud MR murmur, which had been present for many years. Transthoracic echocardiogram (TTE) showed moderate MR. A transesophageal echocardiogram (TEE) revealed a partial flail of the posterior leaflet of the mitral valve resulting in moderate to severe eccentric anteriorly directed MR, amenable to the placement of a MitraClip. Two MitraClips were places, which led to marked improvement in his dyspnea and a decrease in the frequency of thoracenteses for recurrent pleural effusions. A 71-year-old man with wtATTR and a permanent pacemaker was seen in follow-up with marked dyspnea on exertion and fatigue, despite being euvolemic on exam; jugular venous pressure was not elevated but there was a Kussmaul's sign. First and second heart sounds normal and no MR murmur was heard, even in the left lateral position. TTE revealed moderate MR. His symptoms appeared disproportionate to the severity of his amyloid heart disease by exam as he had no evidence of right-sided congestion. It was suspected that the degree of MR was underestimated by TTE. TEE reveled mild diffuse thickening of the mitral valve leaflets with severe, functional MR that was directed centrally. The valve anatomy was suitable for MitraClip, and he underwent successful placement of 2 MitraClips. A 88-year-old man with MR and aortic insufficiency (AI) was seen with a new diagnosis of wtATTR. He had dyspnea on minimal exertion, marked fatigue, 3 pillow orthopnea and paroxysmal nocturnal dyspnea, he was euvolemic on examination, with a Kussmaul's sign, pansystolic and diastolic murmurs. TTE showed severe MR and moderate to severe AI, confirmed with TEE, which also showed the mitral valve was suitable for MitraClip. A single MitraClip was put in situ, with trace residual MR. He noted improvement in his energy and level of dyspnea following. DISCUSSION: It is important to consider other cardiac pathologies that co-exist in wtATTR, which can contribute to patients’ symptoms and are amenable to intervention. These cases demonstrate that MitraClip is feasible in MR in CA with careful patient selection.