Emergent cardiac surgery during transcatheter aortic valve implantation (TAVI): a weighted meta-analysis of 9,251 patients from 46 studies

Aims: Transcatheter aortic valve implantation (TAVI) is a novel treatment option for high surgical risk patients with severe symptomatic aortic valve (AV) stenosis. During TAVI, some patients may require emergent cardiac surgery (ECS). However, the incidence, reasons and outcomes of those needing ECS remain unknown. Methods and results: We performed a search of the English medical literature using MEDLINE to identify all studies on TAVI and evaluate the incidence of ECS (i.e., within 24 hrs of TAVI) and outcomes for these patients. Forty-six studies comprising 9,251 patients undergoing transfemoral, transapical or trans-subclavian TAVI for native AV stenosis published between 01/2004 and 11/2011 were identified and included in this weighted meta-analysis. Overall, TAVI patients were old (mean=81.3 +/- 5.4 years) and had a high mean logistic EuroSCORE (24.4 +/- 5.9%). Few patients required ECS (n=102; 1.1 +/- 1.1%) and this was marginally higher among those undergoing transapical TAVI as compared to those undergoing transarterial TAVI (1.9 +/- 1.7% vs. 0.6 +/- 0.9%). Data on the reasons for ECS were available in 86% (88/102 patients) and 41% of these (36/88) were performed for embolisation/dislocation of the AV prosthesis, with aortic dissection (n=14), coronary obstruction (n=5), severe AV regurgitation (n=10), annular rupture (n=6), aortic injury (n=14), and myocardial injury including tamponade (n=12) constituting the rest. Mortality at 30 days was about 9-fold higher in patients who did need as compared with those patients who did not need ECS (67.1 +/- 37.9% vs. 7.5 +/- 4.0%). Conclusions: Reported rates of ECS during TAVI were low with embolisation or dislocation of the prosthesis being the most common cause. ECS was associated with grave prognosis with two out of three patients dying by 30 days. Thus, refinement in TAVI technology should not only focus on miniaturisation and improving flexibility of the delivery systems and/or devices - which may have the potential for decreasing aortic dissection, annular rupture, and tamponade - but also incorporate modifications to prevent embolisation/dislocation of the valve.