Introduction of ex vivo perfusion of extended-criteria donor hearts in a single center in Asia.

The shortage of organs for heart transplantation has created a need to explore the use of extended-criteria organs. We report the preliminary use of normothermic TransMedics Organ Care System-an ex vivo approach to preserve extended-criteria brain-dead donor hearts. This System maintains a normal temperature, provides continuous perfusion and oxygenation, reduces ischemic time, and enables additional viability assessment options. In a retrospective single-centre study conducted from April 2020 to March 2023, four extended criteria brain-dead donor hearts were perfused and monitored using the Organ Care System. Suitability for transplantation was assessed based on stable or decreasing lactate levels, along with appropriate perfusion parameters. The Organ Care for use of the Organ Care System were coronary artery disease, left ventricular hypertrophy, high-dose inotrope use in the donor, a downtime exceeding 20 min, and a left ventricular ejection fraction of 40-50%. Three out of the four donor hearts were transplanted, while one was discarded due to rising lactate concentration. The three recipients had a higher surgical risk profile for heart transplant. All showed normal cardiac function and no primary graft dysfunction postoperatively. At 2-3 years post-transplant, all recipients have a ventricular function of > 60%, with only one showing evidence of mild rejection. The Organ Care System enables the successful transplantation of marginal donor organs in high-risk recipients, showcasing the feasibility of recruiting donors with extended criteria. This technique is safe and promising, expanding the donor pool and addressing the organ shortage in heart transplantation in Hong Kong.

Concomitant Hepatorenal Dysfunction and Malnutrition in Valvular Heart Surgery: Long-Term Prognostic Implications for Death and Heart Failure.

Background Strategies to improve long-term prediction of heart failure and death in valvular surgery are urgently needed because of an increasing number of procedures globally. This study sought to report the prevalence, changes, and prognostic implications of concomitant hepatorenal dysfunction and malnutrition in valvular surgery. Methods and Results In 909 patients undergoing valvular surgery, 3 groups were defined based on hepatorenal function (the modified model for end-stage liver disease excluding international normalized ratio score) and nutritional status (Controlling Nutritional Status score): normal hepatorenal function and nutrition (normal), hepatorenal dysfunction or malnutrition alone (mild), and concomitant hepatorenal dysfunction and malnutrition (severe). Overall, 32%, 46%, and 19% of patients were classified into normal, mild, and severe groups, respectively. Over a 4.1-year median follow-up, mild and severe groups incurred a higher risk of mortality (hazard ratio [HR], 3.17 [95% CI, 1.40-7.17] and HR, 9.30 [95% CI, 4.09-21.16], respectively), cardiovascular death (subdistribution HR, 3.29 [95% CI, 1.14-9.52] and subdistribution HR, 9.29 [95% CI, 3.09-27.99]), heart failure hospitalization (subdistribution HR, 2.11 [95% CI, 1.25-3.55] and subdistribution HR, 3.55 [95% CI, 2.04-6.16]), and adverse outcomes (HR, 2.11 [95% CI, 1.25-3.55] and HR, 3.55 [95% CI, 2.04-6.16]). Modified model for end-stage liver disease excluding international normalized ratio and controlling nutritional status scores improved the predictive ability of European System for Cardiac Operative Risk Evaluation (area under the curve: 0.80 versus 0.73, P<0.001) and Society of Thoracic Surgeons score (area under the curve: 0.79 versus 0.72, P=0.004) for all-cause mortality. One year following surgery (n=707), patients with persistent concomitant hepatorenal dysfunction and malnutrition (severe) experienced worse outcomes than those without. Conclusions Concomitant hepatorenal dysfunction and malnutrition was frequent and strongly linked to heart failure and mortality in valvular surgery.

Prevalence and Prognostic Importance of Massive Tricuspid Regurgitation in Patients Undergoing Tricuspid Annuloplasty With Concomitant Left-Sided Valve Surgery: A Study on Rheumatic Valvular Heart Disease.

BACKGROUND: The presence of tricuspid regurgitation (TR) is very common in patients with concomitant left-sided valve disease. Recent studies have advocated an additional grading of massive TR that is beyond severe. The present study sought to characterize the spectrum of TR in patients undergoing tricuspid annuloplasty (TA) and to evaluate the prognostic value of TR severity for post-operative outcome following TA. METHODS: A total of 176 patients who underwent TA with combined left-sided valve surgery, secondary to rheumatic valvular heart disease, were prospectively evaluated. The severity of TR was quantified by effective regurgitant orifice area (EROA) using the proximal isovelocity surface area method. Patients were categorized as having non-massive TR (EROA < 0.6 cm2) or massive TR (EROA ≥ 0.6 cm2). Adverse outcome was defined as all-cause mortality or heart failure requiring hospital admission following TA. RESULTS: A total of 55 (31%) patients were considered to have massive TR. Patients with massive TR had a greater right ventricular dimension but a smaller left ventricular dimension compared with those with non-massive TR. After a median follow-up of 39 months, 35 adverse events occurred. Cox-regression analysis showed that both continuous EROA and dichotomized EROA (massive vs. non-massive TR) were independently associated with adverse events even after multivariable adjustment. Further, Harrell C index demonstrated that the addition of massive TR provided better discrimination ability of a prediction model to known prognosticators following TA. CONCLUSIONS: Massive TR is common and up to 31% of study population had massive TR. Massive TR was associated with adverse outcome in patients undergoing TA. Classification of the severity of TR by quantitative measures and identification of massive TR in patients with concomitant left-sided valve disease are essential when considering the optimal timing of corrective surgery.

Prognostic Value of Tricuspid Valve Geometry and Leaflet Coaptation Status in Patients Undergoing Tricuspid Annuloplasty: A Three-Dimensional Echocardiography Study.

BACKGROUND: The advent of three-dimensional echocardiography (3DE) enables detailed evaluation of the tricuspid valve (TV) apparatus; nonetheless, the clinical value of preoperative 3DE is unknown in patients undergoing tricuspid annuloplasty (TA). The aim of this study was to evaluate the prognostic value of TV geometric parameters and leaflet coaptation status evaluated by 3DE in patients undergoing TA. METHODS: A total of 122 patients who underwent TA during left-sided heart valve surgery were prospectively evaluated. Detailed 3DE was performed before surgery. Adverse outcome was defined as the occurrence of heart failure requiring hospital admission or all-cause mortality following TA. RESULTS: A total of 33 adverse events (17 heart failures and 16 deaths) occurred during a median follow-up of 36 months. Tethering volume (hazard ratio = 1.32; 95% CI = 1.05-1.66; P = .01) and ratio of total leaflet length to closure length (hazard ratio = 1.07; 95% CI = 1.03-1.12; P < .01) were associated with adverse events after adjustment for age, sex, and tricuspid regurgitation vena contracta width. Receiver-operator characteristic curve analysis revealed that tethering volume (area under curve = 0.73) and ratio of total leaflet length to closure length (area under curve = 0.75) were most associated with adverse events at 1-year follow-up. The presence of either a large tethering volume or a low ratio of total leaflet length to closure length was predictive of an adverse outcome 1 year following TA. CONCLUSIONS: Our study suggests that 3DE-derived TV tethering volume and ratio of total leaflet length to closure length are important preoperative measures associated with adverse events in patients undergoing TA.