Heart Transplantation

Indications & Contraindications - Heart Swap Candidates

Indications:

• End-stage HF: NYHA Class III-IV (refractory)
• Severe systolic dysfunction: LVEF <20%
• Poor prognosis: Peak VO2 <10-14 mL/kg/min
• Refractory life-threatening arrhythmias

Contraindications:

• Absolute:
  • Active infection or malignancy
  • Irreversible severe pulmonary HTN (fixed $PVR > 5 \text{ Wood units}$)
  • Irreversible significant renal/hepatic/pulmonary disease (non-cardiac)
  • Active substance abuse; severe non-compliance
• Relative:
  • Age >65-70 years
  • Severe obesity ($BMI >35 \text{ kg/m}^2$)
  • Poorly controlled DM with end-organ damage
  • Significant PVD/CVD

⭐ Most common indications: End-stage ischemic cardiomyopathy & dilated cardiomyopathy.

Donor Selection & Management - Gifting a Beat

• Brain Death Criteria: Irreversible loss of all brain & brainstem functions.
• Age: Ideal <55 years (can extend to 65 in select cases).
• Cardiac Function: LVEF >50%, no significant CAD or valvular disease.
• No Active Infection/Malignancy: Screen for HIV, HBV, HCV.
• ABO Compatibility: Identical or compatible.
• PRA Screening: For recipient sensitization; Donor Specific Antibodies (DSA) ideally negative.
• Ischemic Time: Target <4-6 hours.

⭐ Ruling out active infection or malignancy in the donor is critical to prevent disease transmission to the recipient.

Surgical Procedure - Plumbing the Pump

Standard: Orthotopic transplantation (donor heart in normal anatomic position).

• Techniques:

  • Biatrial: Original technique. Involves anastomoses of LA, RA, Aorta, PA.
  • Bicaval: Preferred. Anastomoses of LA, SVC, IVC, Aorta, PA.

    ⭐ Bicaval technique offers improved atrial hemodynamics, ↓ sinus node dysfunction, ↓ tricuspid regurgitation, and ↓ arrhythmias.

• Key Anastomoses (General Order):

  • Left Atrium (LA)
  • Right Atrium (RA) / Superior Vena Cava (SVC) & Inferior Vena Cava (IVC)
  • Pulmonary Artery (PA)
  • Aorta (Ao)
  • 📌 Mnemonic (Biatrial): "Lovely Rita Prefers Apples" (LA, RA, PA, Aorta)

Immunosuppression - Taming the Guard Dogs

• Induction: Basiliximab (IL-2R Ab), Anti-thymocyte Globulin (ATG) for high-risk patients.
• Maintenance: Triple therapy aims for long-term graft survival.

Complications - Trouble in Paradise

• Rejection: Major threat; classified by timing, mechanism, histology.

  Type	Timing	Key Features
  Hyperacute	Mins-Hrs	Pre-formed Ab (ABO/HLA); thrombosis, graft necrosis.
  Acute Cellular	Wks-Mos	T-cell mediated; lymphocytic infiltrate, myocyte damage (ISHLT Grades).
  Antibody-Med.	Days-Wks	Donor-Specific Ab (DSA), C4d+; microvascular inflammation, capillaritis.
  Chronic (CAV)	>1 Yr	Immune & non-immune; diffuse coronary intimal thickening.

• Infections: High risk. CMV (prophylaxis/pre-emptive), Fungal (Aspergillus), PCP.
• Malignancy: PTLD (EBV-driven), ↑Skin Cancers.
• Drug-Related: Renal dysfunction (CNIs), Hypertension, Dyslipidemia, New-onset diabetes.

⭐ Cardiac Allograft Vasculopathy (CAV) is the leading cause of late graft failure and death post-heart transplant.

High‑Yield Points - ⚡ Biggest Takeaways

• Orthotopic heart transplantation (OHT) is the standard surgical approach.
• Bicaval anastomosis is preferred for superior atrial function and fewer arrhythmias.
• Endomyocardial biopsy (EMB) is gold standard for diagnosing acute cellular rejection.
• Maintenance immunosuppression: CNI, antiproliferative agent, and corticosteroids.
• Cardiac Allograft Vasculopathy (CAV) is a major cause of late graft dysfunction.
• Pravastatin reduces CAV incidence and mortality.
• Absolute contraindications: active infection, recent malignancy, fixed severe pulmonary hypertension.