Author + information
- Daniel Kalbacher1,
- Eike Tigges1,
- Florian Deuschl1,
- Niklas Schofer1,
- Johannes Schirmer1,
- Lenard Conradi1,
- Hermann Reichenspurner1,
- Stefan Blankenberg1 and
- Edith Lubos2
MitraClip (MC) implantation is increasingly used and holds the risk to create an iatrogenic and clinically relevant mitral stenosis. Mitral stenosis is associated with atrial fibrillation, left atrium (LA) enlargement and pulmonary hypertension. Case series report mild or moderate stenosis after MC implantation in up to 35% of successfully treated patients. The impact of post-procedural mitral stenosis on long-term outcome has not yet been examined.
From 09/2008-05/2016, a total of 500 patients (age 75.6±8.3 years, male gender 60.4%, logistic EuroSCORE 25.3±17.0%, functional mitral regurgitation (FMR) 66.4%) were treated by MC implantation. Patients were stratified by mean mitral gradient measured by cw-pulsed Doppler on transthoracic echocardiography after MC implantation into three subgroups: 0-4mmHg (subgroup 1), 4-6mmHg (subgroup 2), >6mmHg (subgroup 3).
At baseline, the majority of patients presented with NYHA class III/IV (71% vs. 25%, respectively). Cardiovascular risk factors were equally distributed at baseline within all subgroups. Yet, FMR, cardiomyopathy, history of heart failure and decreased left ventricular ejection fraction were significantly more common in subgroup 1 (FMR 71.4% vs. 59.6% in subgroup 3, p<0.001). Device time and Clip-quantity were comparable (implanted Clips 1.4 ± 0.6). Quality of life improved significantly at 24-month follow-up for all patients. Yet, 6-minute walking distance proved to be significantly different with inferior outcomes for subgroup 3 (median values: 150m vs. 240m for subgroup 2 vs. 350m for subgroup 3, p=0.005). Kaplan-Meier analysis revealed no differences on long-term mortality rates out to 5 years (p log rank = 0.60). For rehospitalization for heart failure, median time to first rehospitalization was again comparable (subgroup 1: 1.03 years, subgroup 2: 0.78 years, subgroup 3: 0.81 years p=0.13).
This single-center, retrospective study failed to show an inferior long-term outcome in patients with a moderate mitral stenosis compared to patients with no/mild stenosis after by MC-implantation. Presupposed this can be confirmed in larger cohorts, this finding could have a relevant impact on intra-procedural decision making.
STRUCTURAL: Valvular Disease: Mitral