Is right-sided heart failure typically systolic or diastolic dysfunction?

Right-Sided Heart Failure: Systolic vs. Diastolic Dysfunction

Right-sided heart failure primarily involves systolic dysfunction, characterized by impaired contractility and reduced right ventricular ejection fraction, though diastolic dysfunction often coexists. 1

Pathophysiology of Right-Sided Heart Failure

Systolic Dysfunction

• Right ventricular (RV) systolic dysfunction is the predominant mechanism in right-sided heart failure, characterized by reduced contractility and impaired ability to eject blood against increased afterload 1
• The RV is thin-walled and adapted to a low-pressure, low-resistance pulmonary circulation, making it highly sensitive to increases in afterload 1
• Acute increases in RV afterload (as in pulmonary embolism) cause abrupt decreases in RV stroke volume with minimal increase in RV systolic pressure 1
• RV systolic dysfunction leads to RV dilation, which promotes tricuspid regurgitation and further worsens RV function 1

Diastolic Component

• While systolic dysfunction predominates, diastolic dysfunction frequently coexists in right-sided heart failure 1
• RV dilation from systolic dysfunction creates ventricular interdependence effects that impair LV filling through septal flattening and pericardial constraint 1
• The combination of RV systolic and biventricular diastolic dysfunction reduces cardiac output and exacerbates peripheral congestion 1

Clinical Presentation and Diagnosis

• Right-sided heart failure presents with systemic venous congestion, peripheral edema, and impaired tissue perfusion 2
• Clinical signs include elevated jugular venous pressure, ankle edema, and as the condition worsens, congestive hepatomegaly and ascites 2
• Diagnosis requires:
  1. Signs of elevated right atrial and venous pressures
  2. Compromised RV function
  3. Evidence of pulmonary hypertension or peripheral edema with congestive hepatomegaly 2

Right-Sided Heart Failure in Different Clinical Contexts

In Heart Failure with Reduced Ejection Fraction (HFrEF)

• RV dysfunction is present in approximately 48% of patients with HFrEF 1
• More common in non-ischemic dilated cardiomyopathy (65%) than ischemic cardiomyopathy (16%) 1
• Associated with 2.4-fold increased risk of mortality, urgent transplantation, or LVAD placement 1

In Heart Failure with Preserved Ejection Fraction (HFpEF)

• RV dysfunction is present in 33-50% of patients with HFpEF 1
• In HFpEF, RV dysfunction can result from secondary pulmonary hypertension due to left heart disease 3
• Patients with HFpEF may develop postcapillary pulmonary hypertension with elevated pulmonary vascular resistance leading to RV systolic failure 3

Imaging Findings

• Echocardiography with tissue Doppler imaging shows that patients with HFpEF have significantly impaired RV longitudinal diastolic and systolic function compared to matched asymptomatic patients 1
• RV dysfunction can be assessed using parameters such as tricuspid annular plane systolic excursion (TAPSE) 1
• Advanced echocardiographic techniques like speckle tracking can detect impaired RV longitudinal systolic and diastolic function that contributes to symptoms 1

Clinical Implications

• RV dysfunction, whether systolic or diastolic, is associated with decreased exercise capacity and worse functional class 1
• The presence of RV dysfunction is universally associated with increased mortality regardless of left ventricular function 1
• Treatment strategies should target both the underlying cause of RV dysfunction and the hemodynamic consequences 2

Common Pitfalls and Caveats

• Right-sided heart failure is often underrecognized, especially in the setting of preserved left ventricular ejection fraction 3
• While systolic dysfunction predominates in right-sided heart failure, the diastolic component should not be overlooked as it contributes significantly to symptoms and outcomes 1
• Declining pulmonary artery pressure in the setting of high pulmonary vascular resistance is an ominous clinical finding indicating decompensating RV function 1
• RV function is highly afterload-dependent, making it difficult to distinguish primary RV pathology from that resulting from secondary pulmonary hypertension 1