Intensive Care Unit-acquired Heart Failure in Critically Ill: the ICU-HF Study

Critically ill patients in intensive care units (ICUs) are exposed to a wide range of complications that can affect long-term morbidity and mortality. Not only the initial diagnosis at the time of admission may lead to complications; the ICU stay itself can also be associated with specific disease patterns. One of the most frequent complications of intensive care treatment is the loss of skeletal muscle mass. Muscle atrophy can be detected in up to 17% of all critically ill ICU patients. This is accompanied by a neuromuscular organ dysfunction collectively referred to as Intensive Care Unit Acquired Weakness (ICUAW). Milder forms of ICUAW are present in up to 40% of all ICU patients, which corresponds to approximately 1.2 million individuals per year in Germany alone. These patients face a multitude of long-term complications and have an increased mortality risk that may persist for up to five years after ICU discharge. To date, the definition of ICUAW is limited to the skeletal musculature of critically ill patients. It remains unclear whether an ICU stay also affects other muscle groups, such as the myocardium. A first retrospective study demonstrated a significant reduction in cardiac muscle mass in critically ill ICU patients. However, the clinical implications of this loss of myocardial mass and the contributing factors remain uncertain. In addition, the patient cohort was highly heterogeneous regarding the initial diagnosis, the intensive care therapies performed (e.g., invasive ventilation), and the findings were based on a small sample size of just 44 patients. Another study investigated the association between skeletal muscle atrophy and myocardial structure in a cohort of 378 community-dwelling older adults. They showed that a decrease in skeletal muscle mass was also accompanied by a reduction in myocardial mass. Furthermore, they found a correlation between skeletal muscle atrophy and reductions in left ventricular and left atrial dimensions. However,