Modified chordal sparing mitral valve replacement as effective technique for both stenotic and insufficient mitral valves.

BACKGROUND: Chordal apparatus preservation is important for preserving left ventricular (LV) function in the long-term perspective. We present results of originally modified chordal-sparing mitral valve replacement (MVR) successfully used in patients with mitral stenosis and mitral insufficiency. METHODS: The modified surgical method involves preserving only four strut chords with portions of the mitral valve leaflets, which are later fixed to the fibrous ring. The rest of the leaflets and marginal chords are removed. RESULTS: Starting from 1998, 484 modified universal chordal-sparing MVR were performed including 270 (55.79%) in patients with rheumatic mitral stenosis and 214 (44.21%) in patients with mitral valve insufficiency. Overall, 116 patients underwent isolated MVR, and 368 patients underwent MRV with concomitant surgical procedures. The overall in-hospital mortality was 2.5% (12 patients). Long-term efficiency was assessed in patients discharged after isolated MVR (114 patients), average follow-up period was 3.1±0.6 years. Preservation of strut chords ensured normalization of intraventricular anatomy and prevented LV dilatation; the LV Sphericity Index is maintained at 0.44-0.63. Heart failure functional class (NYHA) was improved in all patients. Non-fatal prosthesis-related complications were observed in 11 patients (9.65%). Three patients (2.63%) died due to extracardiac causes. CONCLUSIONS: The proposed modification of the strut chordal-sparing mitral valve replacement technique allows preserving functionally complete annulo-papillary apparatus, regardless of the nature of valvular dysfunction, and provides parallel movement to the mechanical prosthesis. This modified surgical technique is safe and effective and eliminates the risk of jamming of the prosthesis disk and left ventricular outflow tract obstruction.

Hypotensive effect of Oxacom® containing a dinitrosyl iron complex with glutathione: animal studies and clinical trials on healthy volunteers.

A comparative study of hypotensive effects of binuclear forms of dinitrosyl iron complexes (DNICs) with glutathione, S-nitrosoglutathione (GS-NO) and sodium nitrite (NaNO(2)) on rats has been carried out. The latter appeared to be the least efficient, viz., mean arterial pressure (MAP) decreased by 10 and 30 mmHg at 25 and 100 µmoles/kg of NaNO(2). In contrast, DNIC and GS-NO produced an appreciable hypotensive effect when used at much lower concentrations. GS-NO reduced MAP to the same extent, viz., to 90 mmHg, on a hundredfold dose scale (from 0.4 up to 50 µmoles/kg) with subsequent restoration of MAP within the next 6-15 min. A similar effect was observed for DNIC except that the amplitude of the MAP drop was lower and the duration of hypotension was essentially greater. DNIC with glutathione were selected as a basic material for pilot-scale production of a hypotensive drug (commercial name Oxacom®). Preliminary pharmacological testing of Oxacom did not establish any adverse or deleterious side effects. Clinical trials of Oxacom® were performed on 14 healthy male volunteers in whom single intravenous infusion of the drug (5mg/kg or 0.2 µmoles/kg of DNIC, respectively) evoked a characteristic response manifested as a 3-4 min drop by 24-27 mmHg of both diastolic and systolic AP with its subsequent slow restoration within the next 8-10h. The heart rate was quickly normalized after an initial increase. Cardiac output was unchanged despite reduced cardiac filling. A comprehensive analysis of clinical and biochemical data failed to establish any significant pathological changes in these parameters. The data obtained suggest that Oxacom® can be recommended for the second phase of clinical trials.