Feasibility of Short-Term Use of Ivabradine in Critical Ill Patients Who Have Atrial Fibrillation and Tachycardia.

Background: Ivabradine is approved for heart rate reduction in patients with stable symptomatic heart failure (HF). The United States Food and Drug Administration and Taiwan Central Health Insurance Agency approved the use of ivabradine for patients with chronic stable HF with sinus rhythm, but it has not yet been approved for patients with acute decompensated HF or with atrial fibrillation (AF). Objectives: To investigate whether short-term ivabradine use is feasible in critically ill patients with AF and rapid ventricular response (RVR). Methods: This study retrospectively analyzed 23 patients admitted to an intensive care unit with acute HF and AF-RVR who received ivabradine. All patients initially received a slow IV of amiodarone. Other medications for HF were prescribed according to current HF guidelines. The time taken for ivabradine to reduce HR to 80 beats per minute, referred to as "Time to 80," was measured in each patient. Results: Overall, 69.6 % (16/23) of the patients had New York Heart Association functional class IV HF. In addition, 60.9% (14/23) of the patients required endotracheal intubation and ventilatory support, with more than half receiving vasopressor treatment to manage hypotension. Five patients died during the study period. The surviving patients had a significantly shorter "Time to 80" compared to those who did not survive (p = 0.037). Conclusions: Adding ivabradine to standard treatment might be feasible for critically ill patients with AF and tachycardia. The finding that surviving patients had a shorter "Time to 80" duration than those who did not survive may have clinical implications. However, further investigations are needed to assess its clinical utility.

Association between HOMA-IR and Frailty among U.S. Middle-aged and Elderly Population.

Previous literatures revealed that homeostasis model assessment-estimated insulin resistance (HOMA-IR) was one of the cardio-metabolic risk factors. This study was conducted to access the association between HOMA-IR and frailty in the United States of America (U.S.) middle-aged and elderly high-risk insulin-resistant population. In the National Health and Nutrition Examination Survey (NHANES III) from 1988 to 1994, the study included 3,893 participants. In order to exam the association between HOMA-IR and frailty in the middle-aged and elderly population through the regression model adjusted for multiple covariates, we divided the participants into middle aged group (Age <65 years) and elderly group (Age > = 65 years) in this study. Each group was then divided into tertiles depending on their HOMA-IR levels. Higher level of HOMA-IR was significantly associated with frailty in the elderly group, but this association was not seen in the middle-aged population. These results demonstrated that the HOMA-IR level can be a novel risk assessment of frailty in elderly high-risk insulin-resistant individuals (Age > = 65 years).