Therapeutic hypothermia in cardiology – a growing field?

Major improvements in outcome after acute cardiac conditions have been observed in Europe over recent decades. The introduction of modern reperfusion therapy with thrombolysis or preferable primary percutaneous coronary intervention (PCI), as well as tailored antithrombotic therapy, have without doubt improved survival after a ST-elevation myocardial infarction (STEMI), and the focus on both pre- and in-hospital care has doubled survival in some countries after an out-of-hospital cardiac arrest (OHCA) over the same time period. Both OHCA and STEMI often require immediate help from both laypeople and health care professionals. Modern management of these conditions therefore requires a large setup involving public awareness of symptoms, immediate first aid and the dispatching of appropriate pre-hospital medical services with telemedicine, allowing for optimal referral of patients for hospital admission and acute interventions, including acute coronary angiography, PCI and targeted temperature management (TTM) in selected patients. Both pre- and in-hospital care of OHCA patients have changed dramatically over the last two decades, despite very few positive randomized clinical trials in this field. Even though the efficacy of each individual element of post-cardiac arrest care may be questioned, the combined bundle of care has been shown to be associated with improved outcome in observational studies.1 In the current issues of this journal, Sulzgruber and colleagues demonstrate that 6-month survival after OHCA has improved from 28% in 1992–1998 to 43% to 2006–2012.2 This Austrian, single-centre, observational study reports from a comprehensive database that is in excess of 4000 patients and also demonstrate improvements in bystander cardiopulmonary resuscitation and decreasing time to first medical contact, as well as increasing application of TTM and PCI, over this 20-year period. TTM and PCI were implemented in the period 1999–2005, and unlike PCI, utilization of TTM increased further from 1999–2005 to 2006–2012. Most of the increase in survival was seen from 1992–1998 to 1999–2005, indicating the importance of the combined bundle of care, rather than simply focussing on PCI and TTM.