Maciej Grabowski

Role of β2-microglobulin in postoperative cognitive decline

AIM β2-microglobulin (β2M) was proved to affect hippocampal functions in mice. MATERIALS & METHODS Seventy-one patients undergoing aortic valve replacement were analyzed in prospective observational study. Kidney biomarkers and Mini Mental State Examinations (MMSEs) were performed before procedure, at discharge and after 6 months. RESULTS Patients with β2M increase over the median change (>0.42 mg/l) experienced a significant in-hospital drop in MMSE (p = 0.005). Patients with β2M increase over the median change also failed to improve a delayed-word-recall domain of the test (p = 0.826) while patients with a lower increase improved results in the domain (p = 0.004). After 6 months, MMSE improvement was associated with a significant decrease in β2M (p = 0.042). CONCLUSION These are the first in man data demonstrating relation between changes in cognition and β2M. The phenomenon was reversible which indicates its therapeutic potential.

Serum beta-2 microglobulin levels for predicting acute kidney injury complicating aortic valve replacement

OBJECTIVES Acute kidney injury complicating both transcatheter and surgical aortic valve replacement is associated with high rates of morbidity and mortality. The aim of this study was to investigate the role of serum beta 2 (β2) microglobulin, cystatin C and neutrophil gelatinase-associated lipocalin levels in detecting periprocedural acute kidney injury. METHODS Eighty consecutive patients who were 70 years of age or older and who were having surgical (n = 40) or transcatheter (n = 40) aortic valve replacement were recruited in a prospective study. The biomarkers were tested before the procedure, 6 times afterwards, at discharge and at a 6-month follow-up visit. RESULTS The baseline β2-microglobulin level was the strongest predictor of acute kidney injury as a complication of transcatheter aortic valve replacement [odds ratio (OR) 5.277, P = 0.009]. Its level 24 h after the procedure reached the largest area under the curve (AUC) of 0.880 (P < 0.001) for detecting acute kidney injury. In multivariate logistic regression analysis, the levels of β2-microglobulin and cystatin C 24 h after the procedure were significantly associated with acute kidney injury after transcatheter valve replacement (OR 38.15, P = 0.044; OR 1782, P = 0.019, respectively). In the surgical aortic valve replacement group, the highest AUCs belonged to β2-microglobulin and cystatin C at 24 h (AUC = 0.808, P = 0.003 and AUC = 0.854, P = 0.001, respectively). Their higher values were also associated with acute kidney injury (OR 17.2, P = 0.018; OR 965.6, P = 0.02, respectively). A persistent increase in the postoperative levels of β2-microglobulin following acute kidney injury was associated with the progression of chronic kidney disease for 6 months after both transcatheter (OR 6.56, P = 0.030) and surgical (OR 7.67, P = 0.03) aortic valve replacements. CONCLUSIONS Serum β2-microglobulin had the potential to predict acute kidney injury complicating transcatheter valve replacement and to diagnose it as early as 24 h after both the transcatheter and the surgical procedures. Furthermore, the serum level of β2-microglobulin was indicative of the progression of chronic kidney disease.

Radiofrequency pulmonary veins isolation of atrial fibrillation in patients undergoing mitral valve replacement

Introduction: Pulmonary veins isolation (PVI) is useful method in patients (pts) with mitral valve disease (MVD) and chronic atrial fibrillation (AF) during prosthetic valve implantation.The aim of the study: To evaluate e.ectiveness of PVI in the treatment of AF in pt with MVD during valve implantation.Material and methods: 45 pts (mean age 55 yrs) with AF were operated on for MVD.RF ablation around the pulmonary veins, a lesion between them and to the mitral annulus were performed. There were 44 prostheses implanted, 1 case of mitral valve annuloplasty, associated with tricuspid valve repair (5 pts), aorto-coronary bypass procedure (2 pts), ASD II closure (1 pt).Results: SR was achieved in 2 (44,5%) pts, 21 (46,5%)pts were in AF, 4 (9%) pts needed pacing. No correlation between SR restoration and preoperative echocardiographic parameters, age, gender, NYHA functional class were found. In long-term follow-up 1 pt have reversed AF to SR spontaneously. There were 6 cases of paroxysmal AF,1 pt needed pacemaker implantation. 20 (44,5%) pts are in SR, 20 (44,5%) in AF, 5 (11%) in permanent pacing.Conclusion: PVI with RF use is effective in restoring sinus rhythm in patients with chronic AF secondary to mitral valve disease.