In-Series Transcatheter Aortic Valve Replacement-in-Transcatheter Aortic Valve Replacement: ACURATE neo Transcatheter Heart Valve Degeneration Successfully Managed with Myval, Avoiding Coronary Flow Obstruction-A Case Report.

•Durability is vital for transcatheter aortic valve replacement in younger patients.•Aortic insufficiency is one of the features of structural valve degeneration.•Degenerated ACURATE neo can be treated with low implantation of an oversized Myval.

Renal effects of N-acetylcysteine in patients at risk for contrast nephropathy: decrease in oxidant stress-mediated renal tubular injury.

BACKGROUND: N-Acetylcysteine has been shown to protect against contrast nephropathy, although the mechanisms underlying such an effect are unclear. Surprisingly, studies have shown that post-radiocontrast renal function actually improves in chronic renal failure patients receiving N-acetylcysteine. However, there have been no studies investigating the cause of this improvement. METHODS: In a double-blind, placebo-controlled study, 24 patients (aged 65+/-2 years) suffering from stable mild-to-moderate renal insufficiency and undergoing elective coronary angiography were randomized to receive either placebo or N-acetylcysteine. All received similar hydration. Renal function parameters were assessed 48 h before and 48 h after radiocontrast administration. Urinary 15-isoprostane F2(t), a specific marker of oxidative stress, was measured immediately before and after the procedure. Expression of urinary alpha-glutathione S-transferase protein, a specific proximal tubular injury marker, was assessed after the procedure. RESULTS: Comparing creatinine clearance values before and after angiography, a significant increase was seen in N-acetylcysteine patients (44.7+/-4.2 vs 57.2+/-6.3 ml/min/1.73 m(2); P = 0.02), whereas placebo patients presented no change (46.6+/-5.0 vs 46.9+/-4.3 ml/min/1.73 m(2); P = 0.90). After radiocontrast, urinary 15-isoprostane F2(t) levels in placebo patients increased significantly over baseline values (2.9+/-0.7 vs 10.3+/-2.1 ng/mg creatinine; P = 0.007), whereas urinary 15-isoprostane F2(t) levels in N-acetylcysteine patients remained basically unchanged (3.5+/-0.5 vs 4.1+/-0.9 ng/mg creatinine; P = 0.63). Furthermore, N-acetylcysteine treatment led to lower levels of alpha-glutathione S-transferase than did placebo treatment (0.8+/-0.2 vs 2.4+/-0.7 micro g/g; P = 0.046). CONCLUSIONS: In chronic renal failure patients, the improvement in renal function induced by post-radiocontrast administration of N-acetylcysteine is strongly associated with suppression of oxidant stress-mediated proximal tubular injury.