Episode Details

1. Core Typology & Risk Factors

• HFrEF (Systolic): EF < 40%. LV is dilated/hypertrophied, unable to eject blood effectively, reducing CO.
• HFpEF (Diastolic): EF ≥ 50%. LV is stiff, noncompliant, causing high filling pressures and decreased filling volume.
• Causes: HTN and CAD are primary. Long-term HTN control reduces HF incidence by 50%.

2. Pathophysiology: The Compensation Trap

• Trigger: Myocardial injury -> decreased CO.
• Cascade:
  1. RAAS: Renal hypoperfusion triggers renin release, converting angiotensinogen to Angiotensin I, then Angiotensin II (vasoconstrictor). This stimulates water/sodium retention (via aldosterone/ADH) and myocardial fibrosis.
  2. SNS: Baroreceptors sense low BP, releasing catecholamines to increase HR and contractility, raising myocardial O2 demand.
• Remodeling: Chronic SNS/RAAS activation forces ventricular dilation/hypertrophy, making the heart more spherical and less effective, further declining LVEF.
• Counter-Regulation: Natriuretic peptides (ANP/BNP) promote vasodilation and diuresis, opposing RAAS/SNS.

3. Left vs. Right HF

• Left-Sided (Pulmonary Congestion): LV failure backs fluid into the left atrium/pulmonary bed. Signs: Dyspnea, orthopnea, paroxysmal nocturnal dyspnea (PND), bilateral crackles, displaced PMI, and pink, frothy sputum.
• Right-Sided (Systemic Congestion): RV failure backs fluid into systemic veins. Signs: JVD, peripheral pitting edema, abdominal ascites, and hepatomegaly. Left HF is the primary cause of Right HF.

4. ADHF & Diagnostics

• Profiles: Congestion (Wet/Dry) and perfusion (Warm/Cold). Wet-Warm (congested but perfused) is most common. Wet-Cold (fluid overload + hypoperfusion: cool extremities, low urine output, altered mentation) is critical, risking cardiogenic shock.
• Diagnostics: Echocardiogram is the gold standard for LVEF/structure. BNP/NT-proBNP levels correlate with LV failure severity and fluid retention.

5. Pharmacotherapy & Interventions

• HFrEF Survival Drugs: ACEi/ARBs/ARNIs (Sacubitril/Valsartan) and Beta-blockers (Metoprolol succinate, carvedilol) block neurohormonal activation and reverse remodeling. Aldosterone antagonists (spironolactone) and SGLT-2 inhibitors (dapagliflozin) reduce mortality.
• ADHF Management: Loop diuretics (furosemide) reduce preload/congestion (monitor K+/Mg++). Vasodilators (Nitroglycerin, Nitroprusside) decrease preload/afterload. Short-term IV Inotropes (Dobutamine, Dopamine) support low CO.
• Nursing Priorities: High-Fowler's position reduces venous return. Monitor daily weights (same scale/clothes before breakfast); notify provider of weight gain >3 lbs in 2 days or 5 lbs in a week.