Definition

Chronic Heart Failure

Chronic heart failure is a clinical syndrome characterized by typical symptoms such as fatigue, shortness of breath, and exercise intolerance due to fluid retention in the lungs, legs, blood vessels, gastrointestinal tract, and sometimes the abdominal cavity. Chronic heart failure is caused by structural and/or functional changes in the heart (e.g., after a heart attack, due to long-standing hypertension), leading to reduced cardiac output at rest and during exertion ^{1, 2}.

Chronic Respiratory Failure

Respiratory failure can be caused by various lung diseases such as COPD, asthma, pulmonary fibrosis, sarcoidosis, infections, or tumors ³. The most common cause of chronic respiratory failure, and the third leading cause of death worldwide, is COPD. Approximately 70% of COPD cases are attributed to cigarette smoking ⁴.

Impact on Metabolism and Nutritional Status

Chronic Heart Failure

The prevalence of cardiac cachexia varies between 8-42%, depending on the definition and study population ². Complex neurohormonal and immunological changes lead to a persistent catabolic state. Elevated plasma levels of catecholamines, cortisol, aldosterone, and renin, as well as steroid and growth hormone resistance and activation of inflammatory cytokines, seem to play an essential role in the development of cardiac cachexia. Gastrointestinal edema, caused by blood stasis, leads to malabsorption and loss of appetite. Shortness of breath and fatigue reduce physical activity, leading to muscle mass loss ^{2, 3, 5}.

Chronic Respiratory Failure

Tissue hypoxia, aging processes, increased work of breathing, elevated resting metabolism, and chronic inflammatory processes lead to a catabolic metabolic state. Anorexia with a consequent decrease in oral food intake occurs more frequently in patients with COPD. It is assumed that hypoxia per se negatively impacts appetite. Additionally, chewing and swallowing may be reduced due to restricted breathing, particularly during acute COPD exacerbations ³. The corticosteroids often used in COPD treatment further contribute to muscle mass loss. This affects respiratory muscles as part of a vicious cycle, worsening respiratory insufficiency and ultimately leading to respiratory failure.

The energy requirements of polymorbid hospitalized patients can be determined using indirect calorimetry or estimated using predictive equations (e.g., Harris-Benedict) and weight-based formulas. However, the accuracy of predictive equations and weight-based formulas in this population is limited ^{6, 7}.

A minimum intake of 75% of the calculated energy and protein needs should be achieved to reduce morbidity and mortality ⁶.

Nutrient requirements for patients with lung or heart disease require adjustments for malnourished patients, physical activity levels, and patient age. The weight used is the Adjusted Body Weight (ADJ) if BMI is ≥28; otherwise, the pre-hospitalization body weight is used ³. BW = Body Weight; d = Day

Vitamins, Minerals, and Trace Elements

• Documented or suspected micronutrient deficiencies should be supplemented ⁶. No specific recommendations for the supplementation of micronutrients exist ².
• Specific to heart failure:
• Limit salt intake to 2.3 g sodium (6 g salt/day) ⁹.
• Actively screen for iron deficiency and provide supplementation if identified; intravenous iron administration appears to be superior to oral therapy in these patients ².

Goals of Nutritional Therapy

• Maintain/improve nutritional status and physical function.
• Prevent malnutrition and nutrient deficiencies.
• Avoid fluid and salt overload in patients with heart failure.
• Provide frequent, small meals to prevent postprandial dyspnea, aiming for improved compliance in patients with chronic respiratory failure.

To identify malnourished patients early, a Nutritional Risk Screening should be conducted at least twice a year.

Energy and protein requirements should be met through oral nutrition whenever possible. If less than 75% of the requirements are met despite enrichment, snacks, or oral nutritional supplements, enteral nutrition should be initiated no later than after 5 days. Complementary parenteral nutrition is indicated when less than 75% of the requirements are covered through oral and/or enteral nutrition. For details, see the chapter on enteral and parenteral nutrition (Link).

Oral Nutrition

Diets for Cardiovascular Risk Optimization

Diets such as low-fat, low-carbohydrate, Mediterranean, and DASH diets can reduce cardiovascular risk when combined with other lifestyle measures (weight reduction, increased physical activity, salt restriction, and limited alcohol consumption). These diets should be individually recommended based on patient preferences. However, long-term data on their effects are lacking.

Enteral and Parenteral Nutrition

Heart Failure

Although evidence from high-quality studies is lacking, enteral/parenteral nutrition is recommended for managing cardiac cachexia to prevent further weight loss. Enteral/parenteral nutrition as a prophylaxis for cardiac cachexia is not recommended.

Aside from monitoring volume status, there are no contraindications for enteral/parenteral nutrition in patients with heart failure.

Chronic Respiratory Failure

There are no data on enteral/parenteral nutrition in patients with COPD. However, expert opinion suggests that balanced enteral nutrition is indicated for treating cachexia in patients with chronic respiratory failure.

Monitoring

In the absence of studies, no specific recommendations can be provided.

Caution: Risk of Refeeding Syndrome (Rec 11, ESPEN guidelines for polymorbid patients ⁶).