Randomized controlled trial of remote ischaemic conditioning in ST-elevation myocardial infarction as adjuvant to primary angioplasty (RIC-STEMI).

Abstract

To test whether remote ischaemic conditioning (RIC) as adjuvant to standard of care (SOC) would prevent progression towards heart failure (HF) after ST-elevation myocardial infarction (STEMI). Single-centre parallel 1:1 randomized trial (computerized block-randomization, concealed allocation) to assess superiority of RIC (3 cycles of intermittent 5min lower limb ischaemia) over SOC in consecutive STEMI patients (NCT02313961, clinical trials.gov). From 258 patients randomized to RIC or SOC, 9 and 4% were excluded because of unconfirmed diagnosis and previously unrecognized exclusion criteria, respectively. Combined primary outcome of cardiac mortality and hospitalization for HF was reduced in RIC compared with SOC (n = 231 and 217, respectively; HR = 0.35, 95% CI 0.15-0.78) as well as each outcome in isolation. No difference was found in serum troponin I levels between groups. Median and maximum follow-up time were 2.1 and 3.7years, respectively. In-hospital HF (RR = 0.68, 95% CI 0.47-0.98), need for diuretics (RR = 0.68, 95% CI 0.48-0.97) and inotropes and/or intra-aortic balloon pump (RR = 0.17, 95% CI 0.04-0.76) were decreased in RIC. On planned 12months follow-up echocardiography (n = 193 and 173 in RIC and SOC, respectively) ejection fraction (EF) recovery was enhanced in patients presenting with impaired left ventricular (LV) function (10% absolute difference in median EF compared with SOC; P < 0.001). In addition to previously reported improved myocardial salvage index and reduced infarct size RIC was shown beneficial in a combined hard clinical endpoint of cardiac mortality and hospitalization for HF. Improved EF recovery was also documented in patients with impaired LV function.