The aim of this study was interpret the existential construct of family caring following Acute Coronary Syndrome. Family support is known to have a positive impact on recovery and adjustment after cardiac events. Few studies provide philosophically-based, interpretative explorations of carer experience following a spouse's ischaemic event. As carer experiences, behaviours and meaning-making may impact on the quality of the support they provide to patients, further understanding could improve both patient outcomes and family experience. Fourteen spouses of people experiencing Acute Coronary Syndrome in Sydney, Australia were engaged in a single, semi-structured interview. Interviews were audio-recorded and transcribed verbatim. Data were analysed using hermeneutic interpretation within a Heideggerian phenomenological framework. Acute Coronary Syndrome disrupts lived temporality, and the projected potential for carers' being-alongside. Carers experienced an existential uncertainty that arose from difficulty in diagnosis, and situated fear as an attuned, being-towards-death. They constructed protective strategies to insulate their partner and themselves from further stress and risk, however, unclear boundaries for protection heightened carer anxiety. The existential structure of care included one of two possible Heideggerian modes: leaping-in care was a dominating mode that required a high level of carer vigilance leaping-ahead care was a metaphorical walking alongside, as carers gave back control, freeing opportunities for the person to 'own' care. Supporting carers through the intensive phase of leaping-in care, and equipping them for informed leaping-ahead care should be a focus in both the acute and post-discharge care phases.