Biventricular Heart Failure (Combined Right and Left Heart Failure)
The most likely cause is biventricular heart failure, which represents the simultaneous dysfunction of both left and right ventricles, producing the complete constellation of pulmonary congestion (dyspnea, basal crackles) and systemic venous congestion (ascites, lower limb edema). 1
Clinical Reasoning
Why Biventricular Failure Best Explains This Presentation
Dyspnea and basal crackles indicate left-sided cardiac dysfunction causing pulmonary venous hypertension and pulmonary edema, as fluid accumulates in the pulmonary interstitium due to elevated pulmonary capillary wedge pressure. 1, 2
Ascites and lower limb edema result from elevated right atrial pressure and systemic venous congestion, which are hallmarks of right-sided cardiac dysfunction. 1
The combination of pulmonary findings with systemic congestion points to cardiac rather than hepatic etiology and specifically indicates involvement of both ventricles. 1
Why Other Options Are Less Likely
Isolated Right Heart Failure (Option A):
- Would not typically present with basal crackles, which specifically indicate pulmonary congestion from left-sided dysfunction. 1
- Right heart failure alone produces systemic venous congestion (ascites, edema) but spares the pulmonary circulation unless there is secondary pulmonary hypertension.
Isolated Left Heart Failure (Option B):
- Would not typically present with ascites, which is a late finding of severe right-sided congestion. 1, 3
- Left heart failure primarily causes pulmonary symptoms (dyspnea, crackles) with peripheral edema only in advanced stages, but ascites is uncommon without right ventricular involvement.
Liver Cirrhosis (Option C):
- While cirrhosis causes ascites and peripheral edema, it does not explain dyspnea and basal crackles unless there is concurrent cardiac disease. 3
- The presence of pulmonary crackles specifically indicates cardiac pulmonary edema rather than hepatic pathology. 1
Pulmonary Embolism (Option D):
- Does not cause the chronic constellation of ascites and bilateral lower limb edema.
- PE may cause acute dyspnea but would not produce basal crackles or chronic systemic venous congestion.
Diagnostic Confirmation
Essential diagnostic steps include:
Elevated natriuretic peptides (BNP >100 pg/mL or NT-proBNP) confirm heart failure diagnosis. 1
Echocardiography is critical to assess both left ventricular systolic/diastolic function and right ventricular dysfunction. 1
Point-of-care ultrasound with B-lines has higher sensitivity and specificity than chest X-ray for detecting pulmonary edema. 1
Pathophysiology
Heart failure causes edema through activation of humoral and neurohumoral mechanisms that promote sodium and water reabsorption by the kidneys, combined with abnormal Starling forces including increased venous capillary pressure. 4
As the heart fails, patients develop dyspnea from pulmonary congestion and peripheral edema and ascites from impaired venous return. 5
In biventricular failure, both pulmonary venous pressure (left-sided) and systemic venous pressure (right-sided) are elevated simultaneously, producing the complete clinical picture described. 1, 6