Heart transplantation

Indication: life expectancy <2 years and/or unacceptable quality of life, end stage CHD, DCM, HCM (see cardiomyopathy)

Risk profile:

PVR (low risk: PVR ≤4 WU or TPG ≤10 mmHg, medium risk: PVR 5-9 WU or TPG 10-20 mmHg)

High risk/contraindicated: PVR >9 WU or TPG ≥15 mmHg. In high risk patients: trial with pulmonary vasodilator in cardiac cath (NO, prostacyclin).

Donor: Size mismatch up to 4:1, good systolic function (EF >50%), serology for EBV, CMV, HIV, HTLV, hepatitis, syphilis, toxoplasmosis

Contraindication: 

Recipient (MDT decision): metastatic incurable neoplasm, severe sepsis, fixed PHT (consider heart-lung transplantation).

Donor: AIDS, HTLV infection or hepatitis B antigen positive.

Preoperative preparation:

ECG, CXR, FBE, clotting, UECs, BNP, LFTs, ABO, HLA, CMV, EBV, HSV, HIV, VZV, measles, hepatitis serology, ECHO, cardiac cath (PVR, TPG), angio CT, MRI, V/Q scan.

Surgery:

Previously biatrial, now commonly bicaval technique.

Postoperative management:

• Keep intubated, ventilated, sedated for 24 hrs, (longer with open chest)
• Inotropes: dobutamine or isoprenaline, milrinone plus adrenaline (despite denervation the donor heart responds well to exogenous inotropes), SNP for increased SVR. Consider potential combination of milrinone and adrenaline 0.05 mcg/kg/min
• Haemodynamics: age donor/recipient adjusted. Early recovery systolic function. Diastolic function longer impaired (milrinone)
• Respiratory: normoxaemia, normocapnea, may consider NO for RV afterload reduction
• Fluid restriction: 1ml/kg/hr
• Haemostasis

Antibiotic prophylaxis until drains removed. PJP prophylaxis. Ganciclovir if donor CMV positive/recipient negative.

Immunosuppression:

Methylprednisolone 15-20 mg/kg/dose BD for 2 days

Thymoglobulin 1.5 mg/kg/dose OD for 5 days or basiliximab

Consider IVIG 0.4 g/kg/dose OD for 5 days

Calci-neurininhibitor: cyclosporine or tacrolimus (0.05 mg/kg/dose BD) adjusted to level

Mycophenolate mofetil (MMF) 30 mg/kg/dose BD or azathioprine 3 mg/kg/dose OD adjusted to level

Specific problems:

• Early graft failure: dominant left heart failure requiring mechanical support: retransplantation
• Right heart failure (especially in setting of preoperatively increased PVR/TPG): iNO, milrinone, dobutamine or adrenaline. Consider mechanical support
• Low CO: keep paralysed; don’t wean inotropes <24 hrs; pacing (infant 140 bpm, adolescent 100 bpm); consider mechanical assist
• Acute rejection (rare in the first 7-10 days): LV dysfunction, arrhythmia. Diagnosis: biopsy shows lymphocytic infiltrates. Therapy: methylprednisolone high dose

Longterm morbidity & mortality:

Renal failure, cardiac allograft disease (CAD), lymphoma, neoplasia, PTLD (post transplant lymphoproliferative disease) usually EBV related.

Therapy: temporarily decrease immunosuppression, rituximab

Outcome:

1y: 90%, 5y: 80%, 10y: 70%

References:

[1] Paediatric Heart Transplant Society: www.uab.edu/phts/

[2] Curr Cardiol Rev. 2011 May;7(2):72-84: Chinnock et al: Heart transplantation for congenital heart disease in the first year of life

[3] Eur J Cardiothorac Surg. 2012 Jun 24. Seddio et al: Is heart transplantation for complex congenital heart disease a good option? A 25-year single centre experience

[4] Curr Treat Options Cardiovasc Med. 2011 Oct;13(5):425-43: Gazit et al: Perioperative management of the pediatric cardiac transplantation patient

[5] Lancet. 2006 Jul 1;368(9529):53-69: Webber et al: Heart and lung transplantation in children

All Marc’s PICU cardiology FOAM can be found on PICU Doctor and can be downloaded as a handy app for free on iPhone or Android. A list of contributors can be seen here.