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Objectives Advantages of aortic valve repair and root reconstruction include maintenance of natural valve hemodynamic parameters and avoidance of prosthetic valve-related complications. However, general acceptance of valve reconstruction may be limited by paucity of long-term follow-up data from only a few centers. This report is intended to supplement existing outcome information for aortic valve repair. Methods Between 2003 and 2013, 200 consecutive patients (149 men, 51 women; mean age, 52.1 years) with significant aortic regurgitation and aortic root enlargement underwent aortic valve repair and associated root reconstruction. The same prospective selection criteria and systematic valve repair approaches were followed throughout the study. Root management consisted of either root remodeling or reimplantation with Dacron prostheses. Kaplan-Meier techniques were used to assess major end points of all-cause mortality, reoperation, and repair failure. Univariable log-rank testing was used to identify associations between risk factors and major events. Results Early mortality was 2% (4 patients), and early repair failure was 3% (6 patients). New York Heart Association functional class was found to be a risk factor for early mortality and morbidity (odds ratio, 3.3; P = .03), whereas crossclamp time and cardiopulmonary time were risk factors for early mortality (odds ratio, 1.04; 95% confidence interval, 1-1.07; P = .01 and odds ratio, 1.02; 95% confidence interval, 1-1.03; P = .02), respectively. Survival at a mean follow-up of 48.6 ± 34.3 months (median follow-up, 43.6 months; range, 17.8-78 months) was 94%, with a freedom from reoperation of 91%. Univariable risk factors for mortality were preoperative New York Heart Association functional class and requirement for root replacement. Repair failure and reoperation were associated with bicuspid valve anatomy, subcommissural annuloplasty, and complex leaflet repair. Freedom from repair failure was associated with aortic reimplantation. Conclusions Data from a prospective cohort of patients undergoing aortic valve repair and root reconstruction reinforce the satisfactory medium-term results obtained with valve reconstruction. Further analysis of these patient outcomes is necessary to draw definitive conclusions on operative techniques.

1,4,-dihydropyridines, belonging to the class of “privileged structures”, are known to protect the heart from stunning, ischemia and ventricular arrhythmias and mainly used in hypertension. The aim of this study was to compare the continuous infusion of parent drug, furnidipine, with its two active metabolites (M-2; M-3) in rat isolated working heart model, where the following parameters were measured and calculated: heart rate, preload pressure, aortic systolic and diastolic pressures (AoD), as well as ± d P /d t , aortic (AF) and coronary flow (CF), oxygen and carbon dioxide partial pressures and pH values in pulmonary effluent, myocardial oxygen consumption. At first, the optimal vasodilatatory dose of M-2 was estimated and afterwards it was compared with equivalent doses of both remaining substances. The strongest vasodilatatory effects were observed after the lowest dose of M-2 was used (10 − 7 M), at the same time being without marked influence on pressure parameters. The pro-drug evoked significantly weaker influence on both flows. Furthermore, furnidipine significantly reduced AoD and AF in comparison to control as well as + d P /d t in comparison to the initial values, while M-2 did not. Both metabolites caused a significant CF increase, but M-3 additionally the AoS and AoD decrease in comparison to the control. Regarding clear differences in the measured parameters between the pro-drug and its metabolites found, the obtained results allow to claim that the metabolites vs. furnidipine possess a beneficial influence. The distinct flow shift from aorta into the coronaries was observed only after M-2 and to a lesser extent — M-3. The cardio-depressant potency of both metabolites is overcome by advantageous vasodilatatory effect. M-2, being a final product, easier to control and at the same time a precursor of the new chemical class of therapeutics, is promising as a cardio-protective agent.

The study was designed to assess whether diazoxide-mediated cardioprotection might be used in human subjects during cardiac surgery.Forty patients undergoing coronary artery bypass grafting were randomized to receive intermittent warm blood antegrade cardioplegia supplemented with either diazoxide (100 micromol/L) or placebo (n = 20 in each group). Mitochondria were assessed before and after ischemia and reperfusion in myocardial biopsy specimens. Myocardial oxygen and glucose and lactic acid extraction ratios were measured before ischemia and in the first 20 minutes of reperfusion. Hemodynamic data were collected, and troponin I, creatine kinase-MB, and N-terminal prohormone brain natriuretic peptide levels were measured. All outcomes were analyzed by using mixed-effects modeling for repeated measures.No deaths, strokes, or infarcts were observed. Patients received, on average, 36.2 +/- 1.2 mg of diazoxide and 37.3 +/- 1.9 mg of placebo (P = .6). Diazoxide added to cardioplegia prevented mitochondrial swelling (8899 +/- 474 vs 9273 +/- 688 pixels before and after the procedure, respectively; P = .6) compared with that seen in the placebo group (8474 +/- 163 vs 11,357 +/- 759 pixels, P = .004). No oxygen debt was observed in the diazoxide group. Glucose consumption and lactic acid production returned to preischemic values faster in the diazoxide group. The following hemodynamic parameters differed between the diazoxide and placebo groups, respectively, in the postoperative period: cardiac index, 3.0 +/- 0.09 versus 2.6 +/- 0.09 L . min(-1) . m(-2) (P = .002); left cardiac work index, 2.81 +/- 0.07 versus 2.31 +/- 0.07 kg/m(2) (P.001); oxygen delivery index, 420 +/- 14 versus 377 +/- 13 mL . min(-1) . m(-2) (P = .03); and oxygen extraction ratio, 29.3% +/- 1.1% versus 32.6% +/- 1.1% (P = .02). Postoperative myocardial enzyme levels did not differ, but N-terminal prohormone brain natriuretic peptide levels were lower in the diazoxide group (120 +/- 27 vs 192 +/- 29 pg/mL, P = .04).Supplementing blood cardioplegia with diazoxide is safe and improves myocardial protection during cardiac surgery, possibly through its influence on the mitochondria.