A Naughty Knot

The occurrence of acute valvular dysfunction immediately following surgical aortic valve replacement (SAVR) is a dramatic intraoperative complication that demands rapid diagnosis. [1,2]e wish to share a case of "a naughty knot" -a simple mechanical obstruction that mimicked refractory myocardial instability.A patient with a bicuspid aortic valve and severe calcific aortic stenosis, featuring preserved left ventricular function, underwent elective SAVR.A 25-mm TTK Chitra tilting disc prosthesis was implanted using standard techniques.The cardiopulmonary bypass (CPB) time was 168 min, with an aortic cross-clamp time of 78 min.Following a standard de-airing protocol and clamp removal, the patient repeatedly experienced ventricular fibrillation (VF) during attempts to wean from CPB.Despite correction of electrolytes and four episodes of asynchronous cardioversion, the arrhythmia persisted.CPB was reinstated, the cross-clamp reapplied, and "hot shot" cardioplegia administered.Upon a second attempt to wean, the patient required maximal inotropic support.