Can postoperative mean transprosthetic pressure gradient predict survival after aortic valve replacement?

Area of Science:

• Cardiology
• Cardiac Surgery
• Medical Devices

Background:

• Aortic valve replacement (AVR) and AVR with coronary artery bypass grafting (CABG) are common cardiac procedures.
• The transprosthetic pressure gradient (TPG) is a measure of prosthetic valve function.
• The impact of TPG on long-term mortality after these procedures requires further investigation.

Purpose of the Study:

• To evaluate the effect of mean transprosthetic pressure gradient (TPG) at 6 weeks post-aortic valve replacement (AVR) or AVR with coronary artery bypass grafting (CABG) on late all-cause mortality.
• To determine if TPG is an independent predictor of long-term survival after AVR or AVR with CABG.

Main Methods:

• A retrospective analysis of 2,276 patients undergoing AVR or AVR with CABG between 1998 and 2012.
• Patients were categorized into low (<10 mmHg), medium (10-19 mmHg), and high (≥20 mmHg) TPG groups based on measurements at 6 weeks.
• Cox proportional-hazards regression analysis was used to identify predictors of late mortality.

Main Results:

• Overall 10-year survival was 67%.
• No significant difference in long-term survival was observed between the low, medium, and high TPG groups (p=0.258).
• Independent predictors of mortality included age, diabetes, peripheral vascular disease, renal dysfunction, COPD, cerebrovascular accident history, and cardiopulmonary bypass time. Prosthesis-patient mismatch and TPG were not significant predictors.

Conclusions:

• Transprosthetic pressure gradient (TPG) measured at 6 weeks post-AVR or AVR with CABG is not an independent predictor of late all-cause mortality.
• Long-term survival does not significantly differ among patients with low, medium, or high TPG after these procedures.