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Page 2 of 17 Cannata et al. Mini-invasive Surg 2020;4:53 I http://dx.doi.org/10.20517/2574-1225.2020.41

INTRODUCTION
Percutaneous repair of mitral regurgitation (MR) with the MitraClip device (Abbott Vascular, Abbott
Park, Illinois, USA) is an established therapeutic option for patients with prohibitive surgical risk and
[1]
anatomically suitable mitral valve (MV) . Implanted in over 100,000 patients worldwide, MitraClip
procedure is safe and boasts a highly favourable risk-benefit ratio. While the impact of percutaneous
MV repair on outcomes in chronic severe symptomatic MR has been evaluated for years in detail, data
regarding the use of percutaneous edge-to-edge procedure in patients with severe acute MR are scarce
and limited to case reports or small-size registries. Acute MR is a complex and heterogeneous pathology,
[2]
with severe hemodynamic consequences and extremely adverse outcomes . Traditionally, in most cases,
after hemodynamic stabilization, the definitive treatment is surgical intervention. Nowadays, the MitraClip
device is proving to be a valuable therapeutic option in high-risk patients.

Hereby, we present a case of acute severe ischemic mitral regurgitation successfully treated with MitraClip
procedure.

CASE DESCRIPTION
We report the case of an 82-year-old female patient, who presented to emergency department for chest
pain lasting for 72 h. The EKG revealed a latecomer lateral ST-elevation myocardial infarction, with ST-
depression in V1-V4, ST-elevation and q waves in V7-V9. She had a history of arterial hypertension,
rheumatoid arthritis, thalassemia minor, and radiotherapy-treated tongue cancer.

A bedside echocardiogram showed a left ventricular ejection fraction (LVEF) of 40% due to akinesia
of posterior and lateral walls, normal left ventricular and atrial dimensions, mild MR, normal right
ventricular function and size. Urgent coronary angiography was performed and showed a flow-limiting
stenosis in the proximal tract of a dominant circumflex coronary artery. The coronary lesion was treated
with balloon angioplasty and implantation of two drug-eluting stents. A severe no-reflow followed and
prompted the use of intraortic balloon pump (IABP) for hemodynamic stabilization and the intracoronary
injection of nitroprusside and adrenaline. The patient was transferred to Coronary Care Unit and remained
hemodynamically stable for the subsequent 24 h.

Then, a sudden hemodynamic collapse occurred, with pulmonary congestion and hypotension requiring
intubation and high-dose vasopressors. Trans-thoracic and trans-esophageal echocardiogram (TEE)
showed acute severe MR with eccentric jet directed towards the posterior wall of left atrium, due to extreme
tethering of the posterior leaflet with partial posteromedial papillary muscle rupture and pseudoprolapse
of the anterior leaflet [Figure 1]. The patient was deemed inoperable due to prohibitive surgical risk (age,
subacute myocardial infarction with no-reflow injury, upper thorax radiotherapy, dual antiplatelet therapy,
hemodynamic instability; STS score - risk of mortality: 66.6%; Euroscore II: 43.52%) and despite the highly
challenging morphology of valvular disease, a salvage MitraClip procedure was the only feasible path. The
mechanism of MR was complex: a Carpentier type IIIC (asymmetric systolic restriction) with a main jet
located at A3-P3 extended to the medial section of A2-P2, plus a partial posteromedial papillary muscle
rupture implicating an additional risk of mechanical complications, a coaptation gap > 10 mm, a posterior
[3]
leaflet of 9 mm, but without calcifications at the grasping zone and with a suitable MV area ( > 4 cm²) .
The patient underwent an urgent percutaneous edge-to-edge procedure under general anaesthesia, with
IABP and vasopressor support, and using fluoroscopic and TEE guidance. An XTR Clip was first implanted
in A3-P3 position with residual moderate MR and mean gradients of 3 mmHg [Figure 2], then an NTR
Clip was used in A2-P2 position with a resulting minimal MR and mean gradients of 4 mmHg [Figure 3].