From the Guidelines
High output heart failure is also referred to as high output cardiac failure or heart failure secondary to circulatory high output conditions. This condition occurs when the heart pumps an increased amount of blood but still cannot meet the body's oxygen demands, as noted in the European Society of Cardiology guidelines 1. It differs from typical heart failure, which involves reduced cardiac output. In high output heart failure, the heart actually pumps more blood than normal, but this increased output is inadequate to meet the body's elevated metabolic needs.
Causes and Treatment
Common causes of high output heart failure include:
- Severe anemia
- Hyperthyroidism
- Arteriovenous fistulas
- Beriberi (thiamine deficiency)
- Pregnancy
- Certain liver diseases like cirrhosis Treatment focuses on addressing the underlying cause rather than using traditional heart failure medications, as emphasized in the guidelines 1. For example, correcting anemia with iron supplements or blood transfusions, treating hyperthyroidism with medications like methimazole, or providing thiamine supplementation for beriberi.
Pathophysiology and Symptoms
The pathophysiology involves peripheral vasodilation and decreased systemic vascular resistance, which increases cardiac workload despite the higher output, as described in the European Heart Journal 1. This eventually leads to cardiac remodeling and symptoms similar to conventional heart failure, including:
- Fatigue
- Shortness of breath
- Fluid retention It is essential to recognize high output heart failure as a distinct entity with different underlying causes and treatment approaches compared to traditional heart failure, as highlighted in the guidelines 1.
From the Research
Definition and Terminology
- High output heart failure is also referred to as high-output cardiac failure 2
- The term "high output heart failure" is considered a misnomer because the heart in these conditions is normal and capable of generating very high cardiac output 2
Alternative Terms
- High-output heart failure (HOHF) is used interchangeably with high output cardiac failure 3, 2, 4, 5, 6
- No other specific alternative terms are mentioned in the provided studies
Characteristics and Diagnosis
- High output heart failure is characterized by an elevated cardiac output, often exceeding 8 L/min or a cardiac index >4 L/min/m² 6
- The diagnosis of high output heart failure is suggested by findings of increased cardiac output, neurohormonal activation, fluid and sodium retention, and a chronic hyperdynamic state resulting in a classic congestive state associated with clinical signs of high output 5