Of the noteworthy studies published this year on the treatment of acute cardiac patients, we would to like to highlight 5 due to their practical impact.
A substudy of the IABP-SHOCK II trial1 has developed a simple score to predict 30-day mortality in patients in cardiogenic shock, based on 480 patients and with external validation. The variables comprising the model were age, history of stroke, glucose at admission, creatinine at admission, lactate at admission, and TIMI flow grade <3 after PCI. According to the score results, patients were classified into 3 risk groups, with a good correlation (C statistic = 0.74) with short-term mortality (23.8%, 49.2%, and 76.6%, respectively).
Another notable study in patients in cardiogenic shock was performed by Ouweneel et al.2 This randomized multicenter study in patients with ST-segment elevation acute myocardial infarction (STEMI), orotracheal intubation, and cardiogenic shock compared the Impella CP percutaneous circulatory support device with the intra-aortic balloon pump (IABP). The study included 48 consecutive patients (24 with the Impella CP and 24 with the IABP). There were no differences between the 2 groups in terms of 30-day mortality: 46% in the Impella CP group and 50% in the IABP group (P = .92). The patients in the Impella group showed higher rates of major bleeding. A limitation of the study is the high percentage of survivors of cardiac arrest (44 of 48), with brain damage as the primary cause of death, which complicates interpretation of the results.
The TTH48 trial concerned cardiac arrest survivors and hypothermia.3 This multicenter and randomized study was performed in survivors of a cardiac arrest of presumed cardiologic origin, with a shockable initial rhythm in 88% of patients, and compared 2 therapeutic hypothermia regimens of different durations. Participants received therapeutic hypothermia at 33°C for either 24hours (n = 179) or 48hours (n = 176). There were no differences between the 2 groups in the primary outcome, good neurological outcome (CPC 1-2 at 6 months): 69% in the 48-hour hypothermia group vs 64% in the 24-hour group (P = .33). The 48-hour hypothermia group had more adverse events and longer mechanical ventilation times. Accordingly, the effectiveness of therapeutic hypothermia vs normothermia remains unclear.
The “prophylactic” use of levosimendan in patients with significant ventricular dysfunction who undergo cardiac surgery is a recurring debate in clinical practice. The results of the multicenter LEVO-CTS study,4 performed in patients with ventricular dysfunction (ejection fraction ≤ 35%) and scheduled for cardiac surgery (revascularization or valve surgery) provide valuable information on this subject. Levosimendan before the procedure (n = 442) was compared with placebo (n = 440). The primary outcome was a composite of 30-day mortality, need for renal replacement therapy at 30 days, perioperative acute myocardial infarction at 5 days, and use of mechanical ventilation at 5 days. There were no differences between the 2 groups (24.5% in the levosimendan group vs 24.5% in the placebo group; P = .98). The incidences of low cardiac output and the need for inotropic agents were significantly lower in the levosimendan group, without affecting the clinical results of the study. Other publications have explored the use of levosimendan during surgical interventions in these patients; the results were similar and there were no benefits on outcomes vs placebo.5
Finally, we would like to highlight the recent DETO2X-SWEDEHEART trial.6 This randomized multicenter study explored the systematic use of oxygen in patients with acute coronary syndrome and baseline saturation > 90%. An oxygen therapy group (6-12hours; n = 3311) was compared with an ambient air group (n = 3318). There were no differences in the primary end point of 1-year mortality (5.0% and 5.1%, respectively; P = .8) or in the other secondary end points. The power of the study was lower than calculated because the authors expected a higher incidence of mortality in both groups, which might be because 24.4% of the included patients had diseases other than heart disease.
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