In the second group of papers there is direct comparison between procedures performed under LA and GA within the same institution. The earliest and smallest study by Behan et al.4 was published in 2008. Twelve consecutive patients undergoing CoreValve procedures were included – nine under LA and three under GA. Not surprisingly, there were no differences between the groups characteristics or outcomes, but they documented one conversion from LA to GA and one death (from respiratory failure) in the GA group. Dehédin et al.5 compare their experience with TAVI under GA (n=91) and under LA (n=34) after a decision was made in March 2010 that LA should be the default for transfemoral procedures. Importantly, preoperative characteristics were similar in both groups, but LA was associated with shorter procedures, shorter length of stay and lower rates of inotrope requirement. Motloch et al.6 have presented their experience with general and LA in an institution where an individualised decision is made. As one might expect, patients undergoing TAVI under LA had higher STS scores and they were also more likely to present with pulmonary hypertension and renal impairment. Despite these adverse factors, procedures under LA were shorter, inotropes were used less commonly and patients mobilised earlier. There were no differences in outcomes or complication rates, although numbers were small (GA 33, LA 41). Intermediate between Dehédin and Motloch, Yamamoto et al.7 report their experience where initially GA (n=44) was generally used but with increasing experience the majority of transfemoral TAVI procedures were performed under LA (n=130). Procedures under LA were associated with shorter ITU and total length of stay. Conversion from local to general anaesthetic occurred in 4.6 % of cases; Durand et al. quote a figure of 3.3 % for conversion to GA, and in both cohorts conversion followed major complications such as tamponade, cardiac arrest, annular and vascular rupture. Ben-Dor et al.8 had an 11 % conversion rate in a cohort of 92 Sapien procedures, of whom 76 % were performed under LA. They noted higher logistic EuroSCORE and a higher incidence of previous stroke in those undergoing procedures under LA. Surgical cut down was less common under LA and procedure duration shorter. In the meta-analysis by Fröhlich et al. the overall rate of conversion from LA to GA was 6.3 %.
Further information about TAVI under LA is indirectly provided by studies assessing non-femoral access routes. Azmoun et al. 17 have reported promising outcomes in a small (n=19) cohort of high-risk patients undergoing TAVI via the carotid artery under LA. Petronio et al.18 have reported outcomes in a cohort of procedures performed via the subclavian artery. LA was used with increasing frequency as operators became more familiar with the procedure and this shift in practice was not associated with any change in outcomes.