Cardiac transplantation: A review of current status and emerging innovations

Table 1 Stepwise evaluation process for heart transplant eligibility

Step	Criteria	Consideration	Outcomes
Initial assessment	End-stage heart failure	Failure of medical and surgical therapies	Proceed to next step if criteria met
	Severe functional limitations (NYHA class III-IV)	Patient quality of life severely affected
Evaluation of comorbidities	Presence of comorbid conditions (e.g., diabetes, renal failure)	Impact of comorbidities on transplant success	Disqualify if comorbidities are too severe
Psychosocial assessment	Mental health status	Ability to adhere to the posttransplant regimen	Disqualify if psychosocial factors are a risk
	Support system availability	Long-term care and support from family or caregivers
Evaluation of contraindications	Active substance abuse	Risk of noncompliance	Disqualify if contraindications present
	Advanced age	Reduced life expectancy
Cardiopulmonary assessment	Pulmonary vascular resistance	Risk of right heart failure posttransplant	Proceed to next step if criteria met
	Lung function tests	Determine compatibility and function
Risk-benefit analysis	Risk of surgical complications	Comparison of survival with and without transplant	Approve if benefits outweigh risks
	Expected posttransplant survival	Evaluation of patient’s overall health status
Final review by transplant committee	Comprehensive review of all assessments	Multidisciplinary team decision	Final decision: Approve or disqualify

NYHA: New York Heart Association.

Table 2 Common systemic complications after heart transplantation

System	Complications
Cardiovascular	Coronary artery disease
	Arrhythmias
	Hypertension
	Graft vasculopathy (cardiac allograft vasculopathy)
Renal	Chronic kidney disease
	Acute kidney injury (often due to immunosuppressive drugs like calcineurin inhibitors)
Pulmonary	Opportunistic infections (e.g., CMV, fungal infections)
	Pulmonary edema
	Pleural effusion
Gastrointestinal	Peptic ulcer disease
	Gastrointestinal bleeding
	Hepatotoxicity (due to medications)
Hematologic	Anemia
	Leukopenia
	Thrombocytopenia
Endocrine	Diabetes mellitus (NODAT)
	Hyperlipidemia
	Osteoporosis
Neurological	Seizures
	Peripheral neuropathy
	Cognitive dysfunction
Infectious	CMV infection
	Bacterial infections (e.g., pneumonia, sepsis)
	Fungal infections (e.g., aspergillosis)
Immunologic	Acute rejection
	Chronic rejection
	PTLD
Musculoskeletal	Myopathy (due to steroids)
	Avascular necrosis
	Osteopenia

CMV: Cytomegalovirus; NODAT: New-onset diabetes after transplantation; PTLD: Posttransplant lymphoproliferative disorder.

Table 3 Overview of mechanical circulatory support devices, indications, complications, and contraindications

Category	Device	Description	Indications	Complications	Contraindications
Left ventricular support	IABP	Uses counter pulsations of a balloon in the descending aorta to improve coronary perfusion and cardiac output	AMI with cardiogenic shock, high-risk PCI	Vascular complications (stroke, limb ischemia), thrombocytopenia, infection	Severe aortic regurgitation, aortic aneurysm, aortic dissection, peripheral vascular disease
	Impella (2.5, CP, 5.5)	Nonpulsatile micro axial flow pumps providing up to 5 L/minute support. Available in various models for different levels of LV support	Cardiogenic shock, high-risk PCI	Bleeding, vascular injury, infection, hemolysis, pump migration	Severe peripheral vascular disease, severe aortic stenosis, LV thrombus, mechanical aortic valves
	HeartMate percutaneous heart pump	Microaxial three-blade impeller pump providing flows up to 5 L/minute	High-risk PCI	Device malfunction, bleeding, thromboembolism	Severe peripheral vascular disease, LV thrombus, mechanical aortic valves
Right ventricular support	Impella RP	Minimally invasive microaxial flow pump providing up to 4 L/minute support for RV	Right ventricular failure, postcardiac surgery	Similar to other Impella devices	Tricuspid regurgitation, pulmonary regurgitation
	TandemHeart	Centrifugal continuous flow pump providing 3.5-5 L/minute support, placed via femoral artery and left atrium	Acute RV failure, especially in postcardiac surgery	Bleeding, thromboembolism, limb ischemia	Aortic regurgitation, peripheral vascular disease
	Protek Duo	Dual-lumen cannula with centrifugal pump for RV support	RV failure, often after LVAD implantation	Similar to other centrifugal devices	Similar to other centrifugal devices
	CentriMag and Rotaflow	Magnetically levitated centrifugal flow pumps providing up to 10 L/minute	Short-term support in severe cases, including postcardiotomy	Bleeding, infection, device failure	Specific contraindications not detailed
	Short-term MCS in structural heart valve interventions	IABP	Used to support patients undergoing valve interventions, but may worsen aortic regurgitation	Structural heart disease, transcatheter valve implantation	Worsening aortic regurgitation
	Impella	Used for aortic stenosis with LV dysfunction, but may worsen stenosis	Aortic stenosis, LV dysfunction	Narrowing of valve orifice, embolic events	Severe aortic stenosis
	TandemHeart	Limited due to transseptal puncture requirements and increased support time	Aortic stenosis, high-risk interventions	Complications of transseptal puncture	Severe aortic stenosis
	ECMO	Provides both cardiac and pulmonary support, can be used in various emergent situations	Cardiopulmonary failure, CPR assistance	Harlequin syndrome, bleeding, infection	Multiorgan failure, severe aortic regurgitation
Long-term mechanical circulatory support	Durable MCS devices	Includes continuous flow devices (axial and centrifugal) and pulsatile devices	End-stage heart failure	Device-related complications and failure	Patient-specific conditions, generally no broad contraindications
	INCOR®	Berlin Heart. First implant 2002, CE mark 2003	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	HVAD®	Medtronic. CE mark 2008, FDA approval BTT 2012, FDA approval lateral implantation 2015	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	HeartMate II®	Abbott Laboratories. First implant 2003, FDA approval BTT 2008, DT 2010	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	HeartMate 3®	Abbott Laboratories. First implant 2014, CE mark 2015	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	EVAHEART 2®	Evaheart Inc. First implants 2005 in Japan, IDE approval by FDA, BTT trial ongoing	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	Jarvik 2000®	Jarvik Heart. First implant 2000, CE mark 2005, FDA approval BTT 2005, DT trial ongoing	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	Heart Assist 5®	Reliant Heart Inc. First implant 1998, CE mark 2001, BTT trial ongoing	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	EXCOR®	Berlin Heart. First implant 1990, CE mark 1996	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	SynCardia total artificial hearts®	SynCardia. First implant 1986, FDA approval BTT 2004	End-stage heart failure	Device-related complications and failure	Patient-specific conditions
	Carmat total artificial hearts®	Carmat SA. First implant 2013, investigational device	End-stage heart failure	Device-related complications and failure	Patient-specific conditions

IABP: Intra-aortic balloon pump; AMI: Acute myocardial infarction; MCS: Mechanical circulatory support; ECMO: Extracorporeal membrane oxygenation; FDA: Food and Drug Administration; PCI: Percutaneous coronary Intervention; LV: Left ventricle; RV: Right ventricle; BTT: Bridge to transplantation; DT: Destination therapy; IDE: Investigational device exemption; LVAD: Left ventricular assist device; CPR: Cardiopulmonary resuscitation.