Single Session Transesophageal Echocardiography and Transcatheter Mitral Valve Repair Using MitraClip in the COVID-19 Era

The 2020 American College of Cardiology expert consensus on the management of mitral regurgitation (MR) recommends initial evaluation of the severity and mechanism of MR by transthoracic echocardiography (TTE) (1). For patients considered for transcatheter mitral valve repair using MitraClip (PMVr), a “diagnostic pre-procedural transesophageal echocardiography (dTEE)” is routinely performed to confirm mechanism, anatomic details, and location of MR and to ascertain the candidacy for PMVr (Figure 1 , left). TEE is superior to TTE for complex pathoanatomy of MR (2). However, for simple primary MR with prolapse or functional MR, if a good quality TTE shows adequate assessment of both anatomy and degree of MR, the yield of TEE is probably minimal and will likely not affect patient selection for PMVr in most patients. The COVID-19 pandemic highlighted new concerns for aerosolization and spread of viral particles via coughing or gagging during TEE. Even in the post-COVID world, a requirement for TEE presents a barrier to treatment for many patients.

Figure 1.

MitraClip Work-Up Flow Chart

(Left) The chart proposed by 2020 American College of Cardiology updated consensus (1). (Right) Modified workflow chart at RWJBarnabas Health-Rutgers Robert Wood Johnson University. CRT = cardiac resynchronization therapy; GDMT = guideline-directed medical therapy; LV = left ventricular; LVEDD = left ventricular end-diastolic diameter; LVEF = left ventricular ejection fraction; MDT = multidisciplinary team; MR = mitral regurgitation; MVA = mitral valve area; NYHA = New York Heart Association; TEE = transesophageal echocardiography; TTE = transthoracic echocardiography.

Given this, our center has considered whether or not a separate dTEE in addition to an intraprocedural TEE is really necessary for scheduling patients for MitraClip. Is intraprocedural TEE alone sufficient for confirmation of clippable MR and ad hoc procedural planning? We simplified work-up and expedited treatment for patients with symptomatic severe MR (3) (Figure 1, right). In patients with severe MR on TTE with favorable PMVr anatomy, our strategy was to have a single session TEE-MitraClip procedure without dTEE (3), similar to patients with a positive stress test to undergo a diagnostic cardiac catheterization and ad hoc percutaneous coronary intervention.

Our single session TEE-PMVr protocol included: 1) assessment of severity and mechanism of MR by TTE; 2) heart team’s decision for MitraClip based on TTE (Figure 1) and telemedicine consultation; and 3) scheduling patients for the TEE-MitraClip procedure.

Patients who had PMVr at our center between January and November 2020, were retrospectively reviewed from an institutional review board–approved database by Rutgers Office of Research Regulatory Affair. Outcomes including procedural success defined as stable placement of MitraClip and reduction of MR to ≤2+, in-hospital complications, and 30-day readmission rates were investigated.

A total of 48 patients with PMVr were divided into 2 groups of before (group 1: n = 18; age 74.3 ± 12.2 years old; 67% males; New York Heart Association 3.06 ± 0.56; Society of Thoracic Surgeons 4.59 ± 1.06) and after (group 2: n = 30; age 76.5 ± 12.2 years old; 60% males; New York Heart Association 3.10 ± 0.48; Society of Thoracic Surgeons 4.65 ± 1.69; p = NS each) implementation of the expedited protocol during COVID-19 restrictions. MR mechanism with Carpentier Classification of 2 was considered primary and 3b considered secondary. MR with both 2 and 3b of Carpentier classification was considered mixed. MR etiology included primary/functional/mixed MR with 8/7/3 patients in group 1 and 14/12/4 patients in group 2 (p = NS). Degree of MR was graded from 1 to 4+ with 4+ as severe and 3+ as moderate to severe (3+). All patients had 3 or 4+ MR with no difference in MR severity (p = NS) in 2 groups (4+ MR: n = 14 in group 1 and n = 21 in group 2). LVEF was 42 ± 10% in group 1 and 44 ± 12% that in group 2 (p = NS). Out of the 30 patients with single-session TEE-MitraClip 1 had the procedure cancelled because on intraoperative TEE we concluded that the patient’s aortic stenosis was the dominate valve lesion and only moderate MR at most even after volume and pressure loads. Procedural success was 100% in the 29 patients who proceeded to MitraClip, with <2+ residual MR in 26/29 (90%) patients compared with group 1 of 18/18 (100%) procedural success, 15/18 (80%) <2+ MR (p = NS each).

No major in-hospital complications (cardiac perforation, tamponade, or death) were observed in either group. Other complications were similar in the 2 groups (1 with acute kidney injury, 3 with atrial flutter/fibrillation, and 1 with pre-existing bifascicular block who developed complete heart block). One readmission occurred within 30 days.

Based on our experience, a 1-stop single-session TEE-PMVr seems safe and feasible in selected patients. One limitation of the expedited single-session TEE-MitraClip is that it may lead to cancelation of procedure on table and potential waste of time of the entire team to avoid improper use of MitraClip for either improper anatomy or degree of MR. Further studies are required to confirm our preliminary results and to determine the proportion of patients who would benefit from this simplified work-up approach for PMVr when preoperative TTE quality is sufficient in evaluation of degree and structural basis of MR.