Validation of Prosthetic Mitral Regurgitation Quantification Using Novel Angiographic Platform by Mock Circulation.

OBJECTIVES: This study aimed to validate a dedicated software for quantitative videodensitometric angiographic assessment of mitral regurgitation (QMR). BACKGROUND: Quantitative videodensitometric aortography of aortic regurgitation using the time-density principle is a well-documented technique, but the angiographic assessment of mitral regurgitation (MR) remains at best semi-quantitative and operator dependent. METHODS: Fourteen sheep underwent surgical mitral valve replacement using 2 different prostheses. Pre-sacrifice left ventriculograms were used to assess MR fraction (MRF) using QMR and MR volume (MRV). In an independent core lab, the CAAS QMR 0.1 was used for QMR analysis. In vitro MRF and MRV were assessed in a mock circulation at a comparable cardiac output to the in vivo one by thermodilution. The correlations and agreements of in vitro and in vivo MRF, MRV, and interobserver reproducibility for QMR analysis were assessed using the averaged cardiac cycles (CCs). RESULTS: In vivo derived MRF by QMR strongly correlated with in vitro derived MRF, regardless of the number of the CCs analyzed (best correlation: 3 CCs y = 0.446 + 0.994x; R = 0.784; p =0.002). The mean absolute difference between in vitro derived MRF and in vivo derived MRF from 3 CCs was 0.01 ± 4.2% on Bland-Altman analysis. In vitro MRV and in vivo MRV from 3 CCs were very strongly correlated (y = 0.196 + 1.255x; R = 0.839; p < 0.001). The mean absolute difference between in vitro MRV and in vivo MRV from 3 CCs was -1.4 ± 1.9 ml. There were very strong correlations of in vivo MRF between 2 independent analysts, regardless of the number of the CCs. CONCLUSIONS: In vivo MRF using the novel software is feasible, accurate, and highly reproducible. These promising results have led us to initiate the first human feasibility study comprising patients undergoing percutaneous mitral valve edge-to-edge repair.

Five-year results of the pilot trial of a sutureless valve.

OBJECTIVE: A prospective trial was designed to evaluate the feasibility of the Perceval sutureless aortic valve. We report the 5-year clinical and hemodynamic outcome. METHODS: A total of 30 patients (mean age: 80.4 ± 3.8 years; mean logistic European System for Cardiac Operative Risk Evaluation [euroSCORE]: 13.2 ± 7.3) received the valve in 3 European centers, between April 2007 and February 2008. Cumulative follow-up was 92.67 patient-years, with a median of 4.2 years. Patients with a small annulus were selected because only sizes 21 and 23 mm (covering annuli diameters from 19 to 23 mm) were available at this early stage of the trial. In 37% of the patients, a 21-mm valve was used; 63% received a 23-mm valve; 14 patients had concomitant coronary artery bypass grafting. Clinical and hemodynamic follow-up evaluation were performed annually, including echocardiography. RESULTS: Procedural success was 100%. Cardiopulmonary bypass time and cross-clamp time in isolated aortic valve replacement were 46.4 ± 6.7 minutes and 29.3 ± 8.0 minutes, respectively. One patient died during the hospital stay. Postoperative complications included 1 patient with mediastinal bleeding, and 1 with atrioventricular block that led to pacemaker implantation. No stroke occurred in either the early or late period. At the last available follow-up, 22 patients were alive. The mean gradient was 9.3 mm Hg, with an effective orifice area of 1.7 cm(2) at 5 years. No dislodgement, structural valve deterioration, hemolysis, or valve thrombosis was reported. CONCLUSIONS: This study reports the first and longest experience with a truly sutureless valve, evaluating implantation feasibility and valve safety. Results from up to 5 years of follow up confirmed the performance and safety of this device, even in a medium- to high-risk patient population with a small aortic annulus.

Aortic valve replacement and concomitant procedures with the Perceval valve: results of European trials.

BACKGROUND: The Perceval (Sorin Group, Milan, Italy) is a self-anchoring sutureless aortic valve prosthesis. We report the short- to midterm results of combined aortic valve replacement (AVR) with concomitant procedures in elderly patients undergoing operation as part of 3 consecutive prospective multicenter European studies. METHODS: From April 2007 to February 2013, 243 patients (mean age, 79.7 ± 5.1 years; female patients, 61%; median EuroSCORE, 9%) underwent AVR with concomitant procedures. The concomitant procedures were coronary artery bypass grafting (CABG) (182 cases), septal myectomy (21 cases), CABG + other procedures (18 cases), and 22 other procedures. Primary and secondary end points included implant feasibility and safety (for mortality and morbidity) and efficacy (New York Heart Association [NYHA] class improvement and hemodynamic results) of the prosthesis at the different follow-up periods. Data were expressed as mean ± standard deviation. Kaplan-Meier analysis was performed for survival analysis. RESULTS: Mean aortic cross-clamp and extracorporeal circulation (ECC) times were 50.7 ± 22.8 minutes and 78.9 ± 32.3 minutes, respectively. Thirty-day mortality was 2.1%. Mean postoperative gradient and effective orifice area were 10.1 ± 4.7 mm Hg and 1.5 ± 0.4 cm(2) and 8.9 ± 5.6 mm Hg and 1.6 ± 0.4 cm(2), respectively, at 1 year. There were early explantations, 4 of which resulted from paravalvular leaks. One additional valve explantation resulted from aortic root bleeding, probably caused by excessively extensive decalcification. In the late period, there was 1 mild paravalvular leak and no intravalvular insufficiency. No migration, dislodgement, or degeneration of the valve occurred during follow-up. Median follow-up was 444 days. CONCLUSIONS: These trials confirm the safety and efficacy of the Perceval sutureless aortic valve, especially in elderly patients requiring AVR + concomitant procedures. In this patient group, sutureless valves may be advantageous compared to transcatheter valve implantations as concomitant procedures other than percutaneous coronary artery angioplasty are not always possible in the latter.

Graft protection in organ transplantation.

Preserving donor organs in optimal condition is a prerequisite for successful transplantation. The donor organ is subjected to a multitude of stresses. In this review, we will discuss the consequences of brain death on donor organs. The effects of an extended ischaemic period followed by the reperfusion necessary for the harvest, storage and implantation of transplant organs will be evaluated. As progressively more is known about the underlying pathophysiological mechanisms, focused and efficient therapeutic interventions can be developed. We will review current organ protection techniques and look at possible future strategies to further improve the final donor organ quality.

Should we ventilate or cool the pulmonary graft inside the non-heart-beating donor?

BACKGROUND: The ideal preservation method during the warm ischemic period in the non-heart-beating donor (NHBD) remains unclear. In this study we compare the protective effect of ventilation vs cooling of the non-perfused pulmonary graft. METHODS: Domestic pigs (30.8 +/- 0.35 kg) were divided into 3 groups. In Group I, lungs were flushed with cold Perfadex solution, explanted and stored in saline (4 degrees C) for 4 hours (HBD, n = 5). Pigs in the 2 study groups were killed by myocardial fibrillation and left untouched for 1 hour. Lungs in Group II were ventilated (NHBD-V, n = 5) for 3 hours. Lungs in Group III were topically cooled (NHBD-TC, n = 5) in situ for 3 hours with saline (6 degrees C) infused via intra-pleural drains. Thereafter, the left lungs from all groups were prepared for evaluation. In an isolated circuit the left lungs were ventilated and reperfused via the pulmonary artery (PA) with autologous, hemodiluted, deoxygenated blood. Hemodynamic, aerodynamic and oxygenation parameters were measured at 37.5 degrees C and a PA pressure of 20 mm Hg. The wet:dry weight ratio (W/D) was calculated after reperfusion. RESULTS: Pulmonary vascular resistance, oxygenation index and W/D weight ratio were significantly worse in NHBD-V (3,774 +/- 629 dyn sec cm(-5), 3.43 +/- 0.5, 6.98 +/- 0.42, respectively) compared with NHBD-TC (1,334 +/- 140 dyn sec cm(-5), 2.47 +/- 0.14, 5.72 +/- 0.24, respectively; p < 0.01, p < 0.05 and p < 0.05, respectively) and HBD (1,130 +/- 91 dyn sec cm(-5), 2.25 +/- 0.09, 5.23 +/- 0.49, respectively; p < 0.01, p < 0.01 and p < 0.05, respectively groups). No significant differences were observed, however, in any of these parameters between NHBD-TC and HBD (p = 0.46, p = 0.35 and p = 0.12, respectively). CONCLUSION: These results indicate that cooling of the pulmonary graft inside the cadaver is the preferred method in an NHBD protocol. It is also confirmed that 1 hour of warm ischemia does not diminish graft function upon reperfusion.

Continuous retrograde blood cardioplegia is associated with lower hospital mortality after heart valve surgery.

OBJECTIVE: Myocardial preservation studies comparing blood and crystalloid cardioplegia techniques were almost exclusively performed on patients undergoing coronary bypass, and they were unable to show a difference in hospital mortality. We investigated possible factors, including cardioplegia techniques, influencing hospital mortality in patients undergoing cardiac valve surgery. METHODS: We evaluated hospital mortality in 1098 consecutive patients undergoing cardiac valve surgery by using a multivariate logistic regression with propensity score balancing of the groups. In 25% of the patients, multiple valve or Bentall procedures were performed, and in 46% of all patients, coronary bypass grafting was associated with valve surgery. A first cohort of 504 consecutive patients were operated on by using single-shot antegrade cold crystalloid cardioplegia, and a second cohort of 594 patients were operated on by using continuous retrograde cold blood cardioplegia. RESULTS: After correction for patient-related and operative risk factors, lower hospital mortality was found in patients who received retrograde blood cardioplegia (P =.020). The odds ratio of in-hospital death when using blood cardioplegia was 0.44 (95% confidence interval, 0.22-0.88). Further predictors of hospital mortality were age, advanced New York Heart Association functional class, cardiopulmonary bypass time, reoperation, active endocarditis, and renal failure. CONCLUSIONS: This study shows that continuous retrograde blood cardioplegia is associated with lower hospital mortality in heart valve operations.