Open repair of complex aortic arch pathologies with the frozen elephant trunk: is it the future?

The ‘frozen elephant trunk technique’, which is a modification of Borst’s ‘elephant trunk technique’ with a stent at the distal part, has broadened the armamentarium of surgeons to treat complex aortic diseases [1–3]. After initial experiences with custom made devices, the prefabricated Jotec Evita FET was introduced. Later, other prefabricated FET grafts were introduced in clinical practice [4, 5]. Initially introduced for the treatment of complex aortic disease (TAA), FET has been expanded to treat dissections, both acute (AADA) and chronic (CAD) [6]. In the present article, Jakob et al. have retrospectively evaluated the results following total aortic arch replacement with frozen elephant trunk (FET) in complex thoracic aortic disease using the Jotec EVITA prosthesis [7]. They have used this technique in different aortic pathologies: acute (AADA) and chronic aortic dissections (CAD) (Stanford Type A and B, DeBakey I) as well as complex thoracic aneurysms (TAA). The authors have correctly understood that these disease entities are different and analysed the results separately. This study represents the largest single centre experience with the Evita FET graft. Despite the extent of surgery, Jakob et al. had excellent peri-operative results. The 30 day mortality was low (10% in AADA, 12% in CAD and 7% in TAA). In follow-up, although the freedom from aorta related deaths at 7 years was 91%, mortality was high. After 7 years, the estimated survival rate in AADA, CAD and TAA were only 55%, 74% and 73%, respectively. Within the discharged patients, arch repair in zone 3 as detected as independent risk factor for death. The question is why? Even though the cardiac ischaemia time was not statistically significant, was it a factor? Although the present study tries to explain to some extent the peri-operative risks after FET technique, we need further information to define optimal indications and reduce risks after complex aortic arch surgery. This study confirms that the treatment of complex aortic arch disease is still associated with significant peri-operative risks. It has to be stressed that FET technique is just one of the tools available to the surgeon to treat complex aortic arch disease. The peri-operative risks of surgical treatment of the aortic arch are mainly procedure dependent, whether the FET technique is used or not. Although, FET technique has given surgeons a novel tool to treat complex thoracic aortic pathologies, it is not a ‘holy grail’. To reduce high pre-operative risks of aortic arch replacements, we need new peri-operative management techniques. ‘Continuous myocardial perfusion’ during aortic arch replacement to reduce myocardial ischaemia time may be one of such techniques [8]. This present study with Jotec Evita and several publications with other FET grafts have shown that FET potentially allows for a ‘single stage’ therapy. In aortic dissections (acute and chronic), the FET facilitates true lumen expansion. If necessary, FET offers an ideal landing zone for endovascular completion without the risk of proximal ‘Ia endo-leak’.