Acute Renal Failure After MitraClip Implantation in Patients with Severe Mitral Regurgitation

Background: Acute kidney injury (AKI) is well known adverse event after cardiac surgery. There is limited on AKI related to percutaneous mitral valve repair (PMVR).

Objectives: To describe the incidence of AKI after PMVL and possible predicting factors.

Methods: We evaluated patients who underwent MitraClip implantation at the Hadassah Medical Center between October 2015 and December 2018. We evaluated immediate and 30-day outcomes after the procedure. Acute renal failure was defined as an increase in serum creatinine by ≥0.3 mg/dl or an increase in serum creatinine (SCr) by ≥1.5 times baseline (according to the latest guidelines for AKI) within the first 5 days after the procedure.

Results: We studied 96 consecutive procedures, a cohort of 92 patients, including 5 redo procedures. 8 patients were on chronic hemodialysis, and hence were excluded. 88 patients were studied, with mean age of 73 years, 67 (76%) patients were male, and mean pre-procedure creatinine 133.14 mmol/l.

31 (35%) patients developed AKI. These patients were more likely to have higher baseline creatinine compared to patients who did not develop AKI – 144.26 mmol/l and 122.02 mmol/l respectively (P < 0.0356). In addition, hemoglobin levels of AKI group were 11.39, compared to 12.35 of non-AKI group (P < 0.007).

No statistically significant difference was noted between the non-AKI and AKI group in terms of age, sex, hypertension, diabetes mellitus, coronary artery disease, LV systolic function, STS, EUROSCORE II or ACEF scores. Multi variant analysis showed that long term treatment with ACE-i had a protective effect for creatinine elevation after PMVL in both groups (P=0.015).

Conclusions: The incidence of AKI after PVMK was 35%. Baseline renal function and hemoglobin were the risk factors in our cohort. Interestingly, ACE-i had a protective effect for creatinine elevation.