Advice

Clinical and technical evidence

Clinical and technical evidence

A literature search was carried out for this briefing in accordance with the interim process and methods statement. This briefing includes the most relevant or best available published evidence relating to the clinical effectiveness of the technology. Further information about how the evidence for this briefing was selected is available on request by contacting mibs@nice.org.uk.

Published evidence

Two studies are summarised in this briefing, including a total of 2,555 patients having a coronary artery bypass graft (CABG).

The evidence for DuraGraft includes 1 randomised control trial (conference abstract) and 1 observational study (full text).

Table 1 summarises the clinical evidence as well as its strengths and limitations.

Overall assessment of the evidence

In general, the evidence suggests that the use of DuraGraft may be associated with a lower risk of developing complications and adverse events after CABG compared with saline solution. However, there is little evidence of the long-term effects of DuraGraft in the context of a randomised, controlled trial. None of the included studies compared the effectiveness of DuraGraft with blood-based solutions, which are commonly used in CABG in clinical practice.

The evidence is limited in quantity; both included studies are not from the UK, which may limit the generalisability of the findings to the NHS. However, patients with coronary artery disease selected to have CABG using the preservation solution are not thought to differ substantially from those seen in NHS practice.

Table 1 Summary of selected studies

Perrault et al. (2017), conference abstract 135

Study size, design and location

A prospective randomised, double-blinded study of 119 patients who had CABG. Seven investigational sites in Canada.

Intervention and comparator(s)

DuraGraft.

Saline solution.

Key outcomes

More patients in the DuraGraft group had mean reduction or no change in wall thickness at 4 to 6 weeks (p<0.0001) and 3 months (p<0.0003) after CABG compared with the heparinised saline group. Results suggested that DuraGraft prevented early increased wall thickness as an expression of intimal hyperplasia. Progressive intimal hyperplasia would contribute to vein graft disease and vein graft failure.

Strengths and limitations

A randomised study design. No long-term outcomes (at 12 months study follow-up) were reported. Details of allocation and randomisation were not reported in the abstract.

Haime et al. (2018)

Study size, design and location

A cross sectional study of 2,436 patients who had CABG.

USA.

Intervention and comparator(s)

DuraGraft.

Saline solution.

Key outcomes

The study included patients aged between 29 and 92 years. During CABG procedures, 1,400 patients had heparinised saline and 1,036 patients had DuraGraft. Patient characteristics and surgical data were similar between 2 groups except patients in the heparinised saline group had a higher prevalence of COPD and previous MI.

Mean follow-up was 8.5±4.2 years for the DuraGraft group, and 9.9±5.6 years in the heparinised saline group. The study examined the differences in short-term and long-term outcomes between the 2 groups.

Short-term outcomes were defined as events occurring in the peri- and early postoperative period within the first 30 days after CABG or before discharge. The study reported the following short-term outcomes: perioperative MI, prolonged ventilation time (>48h), prolonged time in coma (>24h), renal failure, and death. Results suggested that patients in the DuraGraft group had a substantial risk reduction in (77%) perioperative MI compared with those in the heparinised saline group (OR 0.23, 95% CI 0.09 to 0.59; p=0.0024).

Long-term outcomes were defined as events happening >30 days after CABG. Results suggested that treatment with DuraGraft was associated with a significantly lower risk of repeat revascularisation starting at 1,000 days after CABG compared with the heparinised saline group (HR 0.65, 95% CI 0.44 to 0.97, p=0.037). DuraGraft was also associated with statistically lower occurrence of MACE (HR 0.81, 95% CI 0.70 to 0.94, p=0.0051) and statistically significant risk reduction in non-fatal MI (HR=0.55, 95% CI 0.41 to 0.74, p<0.0001) than the saline group.

Strengths and limitations

A retrospective study design. The heparinised saline and DuraGraft groups were observed in 2 sequential time periods, which may have affected outcomes. Most of the study participants were male (99%). Patient characteristics and surgical data were similar for most parameters, but patients in the heparinised saline group had a higher prevalence of COPD and previous MI. The data analysis for this study was supported by an unrestricted grant by Somahlution (the manufacturer).

Abbreviations: CABG, coronary artery bypass; CI, confidence interval; COPD, chronic obstructive pulmonary disease; MACE, major adverse cardiac event; MI, myocardial infarction; OR, odd ratio; HR, hazard ratio.

Recent and ongoing studies