From the Guidelines
Holosystolic murmurs in heart failure are typically caused by mitral regurgitation, which is often manifested clinically by an apical holosystolic murmur, a third heart sound, and a diastolic flow rumble, as noted in patients with severe mitral regurgitation 1.
Causes of Holosystolic Murmurs
The most common causes of holosystolic murmurs in heart failure are:
- Mitral regurgitation: This occurs when the heart chambers dilate and the papillary muscles become dysfunctional, leading to improper closure of the mitral valve during systole.
- Tricuspid regurgitation: This can occur when right ventricular dilation prevents proper valve closure.
Clinical Presentation
These murmurs are typically heard best at the apex (mitral regurgitation) or left lower sternal border (tricuspid regurgitation) and may radiate to the axilla or back.
Management
The presence of these murmurs in heart failure patients indicates worsening cardiac function and volume overload, often requiring adjustment of heart failure medications such as diuretics, ACE inhibitors, or beta-blockers, as well as afterload reduction and administration of diuretics to produce 1.
Prognosis
The murmur's intensity may change with treatment as cardiac dimensions improve and valvular function partially recovers. However, in some cases, such as congenitally corrected transposition of the great arteries (L-TGA), the presence of a holosystolic murmur may be associated with systemic AV valve regurgitation and increased risk of heart failure 1.
From the Research
Holosystolic Murmur in Heart Failure
- A holosystolic murmur is a type of heart murmur that occurs throughout the entire systolic phase of the heartbeat [@\3@].
- In heart failure, a holosystolic murmur can be a sign of mitral regurgitation, which is a condition where the mitral valve does not close properly, allowing blood to flow backward into the left atrium [@\1@, @\2@].
- The use of angiotensin-converting enzyme inhibitors (ACEi) and angiotensin-receptor blockers (ARB) can help reduce the risk of mortality and hospitalizations in patients with heart failure, including those with mitral regurgitation [@\3@].
- However, the relationship between holosystolic murmur and heart failure is complex, and more research is needed to fully understand the underlying mechanisms [@\1@, @\2@, @\3@].
Mechanisms and Treatment
- ACEi and ARB are cornerstones in the treatment of heart failure with reduced ejection fraction (HFrEF), and can help reduce the risk of mortality and hospitalizations [@\3@].
- The use of ACEi and ARB can also help reduce the severity of mitral regurgitation, which can contribute to the development of a holosystolic murmur [@\1@, @\2@].
- Maintaining or initiating patients with HFrEF hospitalized for acute decompensated heart failure on ACEi/ARB is associated with a reduced risk of mortality and 1-year admissions [@\3@].