Mechanical aortic valve prostheses in the small aortic root: Top Hat versus standard CarboMedics aortic valve

Hemodynamic Comparison of the On-X and Top Hat Mechanical Aortic Valve Prostheses

BACKGROUND

There are limited data comparing hemodynamic valve function in mechanical aortic valve prostheses. This study compared the hemodynamic function of 2 commonly used mechanical aortic valve (AV) prostheses, the On-X (Artivion) and Top Hat (CarboMedics Inc) valves.

METHODS

This study was a retrospective analysis of 512 patients who underwent AV replacement with the On-X (n = 252; 49%) or Top Hat (n = 260; 51%) mechanical valves between 2011 and 2019. Patients were matched on the basis of selected variables. Echocardiographic data were collected preoperatively and postoperatively over a median follow-up of 1.39 years.

RESULTS

A total of 320 patients were matched, 160 patients in each group. Despite being matched for left ventricular outflow tract diameter, patients in the Top Hat group received a greater prevalence of smaller tissue annulus diameter valves (≤21 mm) (83% vs 38%; P < .001). Patients in the On-X group had longer aortic cross-clamp times (78 minutes vs 64 minutes; P < .001) during isolated aortic valve replacement. Discharge echocardiography showed no difference in the AV area index between both groups (1.00 cm2/m2 vs 1.02 cm2/m2; P = .377). During longer-term echocardiographic follow-up, the AV area index remained stable for both valves within their respective tissue annulus diameter groups (P = .060).

CONCLUSIONS

There was no difference between the 2 valves with respect to the AV area index at discharge, and hemodynamic function was stable during longer-term follow-up. The longer aortic cross-clamp time observed in the On-X group may indicate increased complexity of implantation compared with the Top Hat group.

Updates on the Latest Surgical Approach of the Aortic Stenosis

Over the last twenty years, we marked significant progresses in the field of tissue engineering and the development of new aortic valve structural and delivery systems. These continuous iterations on the field, have completely changed the surgical indications and approaches for AVR. Nowadays, therapeutic decisions are endorsed by international guidelines; however, new technical advances need a new integrated approach. The clinical scenarios issued from the interaction between the Guidelines and the newest approaches and technologies are regularly on debate by the Heart Team. We will present some of our most encountered situations and the pattern of our therapeutic decisions. To easily navigate through Guidelines and clinical scenarios, we reported in this review a simplified and easy to use Clinical decision-making algorithm that may be a valuable tool in our daily practice.

A Technique for Avoiding Patient-Prosthesis Mismatch in the Small Aortic Root

In the small aortic root, extremely weakened tissue and extensive calcification predispose toward the implantation of small prostheses, anastomotic bleeding, and paravalvular leaks. We describe a procedure in which a "homemade" composite mechanical prosthesis-conduit is implanted in a supra-annular position in two patients with a small aortic root. This technique facilitates the placement of a larger prosthesis, thus avoiding patient-prosthesis mismatch. doi: 10.1111/jocs.12741 (J Card Surg 2016;31:309-310).

Obesity and the risk of late mortality after aortic valve replacement with small prosthesis

BACKGROUND

Whether obesity is related to late mortality with implantation of small aortic prosthesis remains to be clarified. This study was aimed to evaluate the effect of obesity on late survival of patients after aortic valve replacement (AVR) with implantation of small aortic prosthesis (size ≤ 21 mm).

METHODS

From January 1998 to December 2008, 307 patients in our institution who underwent primary AVR with smaller prostheses survived the 30 days after surgery. Patients were defined as normal if body mass index (BMI) was < 24 kg/m2, as overweight if BMI 24-27.9 kg/m2, and as obese if BMI ≥ 28 kg/m2. Data of New York Heart Association (NYHA) functional classification, left ventricular ejection fraction (LVEF), effective orifice area index (EOAI), and left ventricular mass index (LVMI) of the patients collected at the 3rd month (M), 6th M, 1st year (Y), 3rd Y, 5th Y, 8th Y after operation respectively.

RESULTS

By multivariable analysis, obesity was an independent factor of late mortality (hazard ratio [HR]: 1.62; P = 0.01). The obesity and overweight group had more poor survival (p < 0.001) and higher proportion of NYHA class III/IV (p < 0.01) compared with the normal group. Lower EOAI and higher LVMI were found in obesity and overweight group, but we saw no significant difference about LVEF among the three groups.

CONCLUSIONS

Obesity was associated with increased late mortality of patients after AVR with implantation of small aortic prosthesis. Being obese or and overweight may also affect the NYHA classification, even in the longer term. EOAI should be improved where possible, as it may reduce late mortality and improve quality of life in obese or overweight patients.

Current status and future perspectives of prosthetic valve selection for aortic valve replacement

Aortic valve abnormality is the most frequent form of valvular heart disease. Notably, aortic stenosis in the elderly population has been increasingly common. Aortic valve replacement (AVR) using prosthetic valve has been still believed as a gold standard surgical intervention for various types of diseased aortic valve. The numerous reports and studies evaluating the clinical outcomes and durability of prosthesis were revealed, however, prosthesis selection for AVR is still debated. In twenty-first century, paradigm shift of prosthesis preference might be emerged from mechanical valves to bioprosthesis due to the development of the technology. Moreover, transcatheter aortic valve implantation accelerated among the worldwide trends. It could be developed having the potential to reduce the mortality and morbidity associated with high-risk traditional AVR. After the current guidelines for the management of patients with valvular heart disease, we should consider the valve choice in various patients' profile setting. This review summarizes the current status of prosthesis selection and future perspectives of ideal aortic valve intervention, including minimal invasive care.