Status Codes for Heart Transplant Allocation

Status Code	Criteria
Status 1A - ECMO - IABP - Inpatient total artificial heart - Mechanical ventilation - Continuous infusion of a single high-dose intravenous inotrope or multiple intravenous inotropes, and with continuous hemodynamic monitoring of left ventricular filling pressures - LVAD, RVAD, or BiVAD for 30 days - MCS with significant device-related complications (thromboembolism, device infection, mechanical failure, or life-threatening ventricular arrhythmias) -
Status 1B	- Uncomplicated LVAD, RVAD, BiVAD after 30 days have been used - Outpatient total artificial heart - Continuous infusion of intravenous inotro
Status 2	Candidates not meeting 1A or 1B crit
Status 7	Temporarily inactive, most often due to infe

Management

The use of mTOR inhibitors, statins, and vitamins C and E have been demonstrated to slow the progression of CAV.¹

Most maintenance immunosuppressive protocols after HTx use a 3-drug regimen:¹
- a calcineurin inhibitor (CNI) (cyclosporine or tacrolimus)
  - 📝 Tacrolimus is favored over cyclosporine based on clinical trials suggesting that tacrolimus-based immunosuppression is associated with a decrease in acute rejection
- an antimetabolite agent (mycophenolate mofetil [MMF] or azathioprine)
  - 📝 MMF has replaced azathioprine as the preferred antimetabolite, given reduction in mortality and the incidence of treated rejection at 1 year
- tapering doses of corticosteroids over the first year post-transplantation
  - In low-risk patients without a history of rejection or donor-specific antibodies, weaning corticosteroids by 1 year is reasonable.
Proliferation signal inhibitors (PSIs) or mammalian target of rapamycin (mTOR) inhibitors, sirolimus and everolimus, are relatively recent advances in standard immunosuppression.¹
- Both sirolimus and everolimus ↓ incidence of acute rejection and prevent development of cardiac allograft vasculopathy (CAV)
- When sirolimus is used in HTx recipients with significant renal impairment, it permits minimization or complete withdrawal of the CNIs (e.g., tacrolimus), resulting in improvements in renal function without an increased risk of rejection.

⚠️ Given the denervation of the transplanted heart, patients do not experience typical angina. ∴ routine surveillance angiography (cors + IVUS) is performed in cardiac transplant recipients, usually at 1-year intervals.
- IVUS is more sensitive than angiography in detecting CAV
IVUS
- progression of intimal thickening >0.5 mm in the first year after transplantation is associated with an increased risk of death and development of angiographic CAV up to 5 years later
- IVUS findings may trigger a switch from MMF to a proliferation signal inhibitor therapy

Allomap
- gene expression profile test
  - 11-gene expression signature derived from peripheral blood mononuclear cells
  - high Negative Predictive Value for acute cellular rejection

Kittleson, M. M., & Kobashigawa, J. A. (2017). Cardiac transplantation. JACC: Heart Failure, 5(12), 857–868. https://doi.org/10.1016/j.jchf.2017.08.021 ↩ ↩² ↩³