The PETTICOAT concept for endovascular treatment of type B aortic dissection.

INTRODUCTION

A systematic literature search on outcomes of the PETTICOAT technique was aimed at verifying the feasibility and safety of the procedure, comparing clinical outcomes with standard stent-grafting of the proximal entry tear as well as describing the possible benefits in terms of aortic remodeling.

EVIDENCE ACQUISITION

Potentially eligible papers were sought through a computerized search of MEDLINE and SCOPUS databases between January 2006 and June 2016. Key words used for potentially eligible studies were: "dissection," "bare stent," "thoracic," "endovascular," "PETTICOAT". Studies were considered for review on the basis of these criteria: including more than 5 cases, providing full information on the type of dissection treated and the onset of dissection as well as reporting clinical and technical outcomes.

EVIDENCE SYNTHESIS

The literature search identified 11 studies (4 prospective and one controlled) in which the PETTICOAT treatment was employed (439 cases) in type A (N.=40; 9.1%) and Type B (N.=399; 90.9%) dissection complicated by malperfusion in 48.4% of cases with different dissection onsets: acute in 295 cases (67.3%), subacute in 54 cases (12.3%) and chronic in 90 cases (20.5%). Due to the heterogeneity of the cohorts, only the perioperative results of 4 papers (143 patients) reporting a single stage PETTICOAT procedure for the treatment of acute (89 cases) or subacute (54 cases) type B dissection were pooled together. The pooled data demonstrated that the procedure is feasible and safe with an overall 30-day mortality rate of 4.9% and clinical success rate of 90.2%. Six out of 11 papers proposed a clinical comparison between TEVAR alone (TEVAR) and PETTICOAT in the same dissection setting with no clinical success differences reported at short-term. In terms of aortic remodeling 9 out of 11 papers reported the behavior of lumina after the procedure. All studies observed an early significant expansion of the true lumen expansion in the thoracic and abdominal aorta but when false lumen is taken into consideration, the data are more heterogeneous: both the thoracic and abdominal false lumen decreased in size significantly postoperatively due to the redistribution of the lumens but, at follow-up (6 studies), the FL continued to decrease in size in the stent-grafted area, while in the abdominal aorta remained stable with no shrinkage (4 studies) or increased (2 studies at 2 year follow-up).

CONCLUSIONS

Analysis of the literature data, not only does it demonstrate that the PETTICOAT technique is safe and feasible but also that it is able to enhance the effect of the proximal TEVAR improving the re-expansion of the true lumen of the distal thoraco-abdominal aorta possibly improving end-organ perfusion. However, since there is no evidence of improved short and mid-term survival as well as positive remodeling of the false lumen in the distal aorta, when compared to a simple proximal stent-grafting, a wide-spread use of the PETTICOAT technique is not justified and it should be limited to cases complicated by dynamic malperfusion as a bailout adjunctive tool.