Redo aortic valve replacement versus valve-in-valve trans-catheter aortic valve implantation: a UK propensity-matched analysis.

This study sought to compare the morbidity and mortality of redo aortic valve replacement (redo-AVR) versus valve-in-valve trans-catheter aortic valve implantation (valve-in-valve TAVI) for patients with a failing bioprosthetic valve. A multicenter UK retrospective study of redo-AVR or valve-in-valve TAVI for patients referred for redo aortic valve intervention due to a degenerated aortic bioprosthesis. Propensity score matching was performed for confounding factors. From July 2005 to April 2021, 911 patients underwent redo-AVR and 411 patients underwent valve-in-valve TAVI. There were 125 pairs for analysis after propensity score matching. The mean age was 75.2±8.5 years. In-hospital mortality was 7.2% (n=9) for redo-AVR versus 0 for valve-in-valve TAVI, p=0.002. Surgical patients suffered more post-operative complications, including intra-aortic balloon pump support (p=0.02), early re-operation (p<0.001), arrhythmias (p<0.001), respiratory and neurological complications (p=0.02 and p=0.03) and multi-organ failure (p=0.01). The valve-in-valve TAVI group had a shorter intensive care unit and hospital stay (p<0.001 for both). However, moderate aortic regurgitation at discharge and higher post-procedural gradients were more common after valve-in-valve TAVI (p<0.001 for both). Survival probabilities in patients who were successfully discharged from the hospital were similar after valve-in-valve TAVI and redo-AVR over the 6-year follow-up (log-rank p=0.26). In elderly patients with a degenerated aortic bioprosthesis, valve-in-valve TAVI provides better early outcomes as opposed to redo-AVR, although there was no difference in mid-term survival in patients successfully discharged from the hospital.

What is the value of topical cooling as an adjunct to myocardial protection?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'What is the value of topical cooling as an adjunct to myocardial protection?' Using the reported search, 9 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The studies included four randomized controlled trials (RCTs). Two RCTs demonstrated no cardioprotective effects of topical hypothermia as they found no statistically significant differences in myocardial markers between patients with or without topical cooling. In a randomized study of 249 patients undergoing elective cardiac surgery, phrenic nerve injury and failure of extubation occurred more frequently with the use of topical hypothermia with iced slush (P = 0.009 and P = 0.034, respectively). One retrospective analysis found that patients who received iced topical hypothermia had longer postoperative hospitalization, higher incidence of atelectasis and higher left diaphragms on chest X-ray. Another study showed increased morbidity and mortality associated with postoperative diaphragmatic dysfunction resulting from the use of iced slush topical cooling of the heart. We conclude that topical cooling is an unnecessary adjunct to myocardial protection in patients undergoing cardiac surgery. There is no evidence of any additional cardioprotective benefit. Several studies showed that the use of topical hypothermia is associated with phrenic nerve injury, leading to diaphragmatic paralysis and increased pulmonary complications. Moreover, long-term follow-up data showed often incomplete regression of the phrenic nerve paralysis. However, few randomized studies exist on the value of topical cooling as an adjunct to myocardial protection.