Last reviewed: March 2026
Contents
MDM Templates
Cardiac Transplant — General
Patient presents with *** in the setting of cardiac transplant (*** years post-transplant, on ***). Given transplant history, considered increased risk for cardiac allograft vasculopathy, dysrhythmia, rejection, and immunosuppressant-related complications including opportunistic infection, electrolyte derangement, and musculoskeletal injury. Patient is well appearing with reassuring exam. History, exam, and workup do not suggest acute rejection, vasculopathy, or infection.
Plan: Discussed with transplant cardiology. Disposition: Discharge with transplant team follow-up. Return precautions for fever, chest pain, syncope, or new dyspnea.
Cardiac Transplant — Dysrhythmia
Patient presents with *** in the setting of cardiac transplant. The denervated transplant heart has unique arrhythmia considerations. PVCs and PACs are common and typically benign. Bradycardia in the transplant heart reflects SA or AV node dysfunction from surgical trauma rather than vagal tone — atropine is ineffective.
If bradycardia requiring intervention: Epinephrine or isoproterenol infusion for hemodynamically significant bradycardia. Atropine will not work — the transplant heart lacks vagal innervation. Pacing if refractory.
If SVT: Adenosine at half the standard dose (3 mg initial) — the denervated heart has increased sensitivity.
If atrial fibrillation/flutter: New atrial fibrillation in a transplant patient raises concern for acute rejection or structural damage and carries high mortality. Avoid calcium channel blockers (interaction with calcineurin inhibitors). Transplant cardiology consulted emergently.
Cardiac Transplant — Rejection
Patient presents with *** concerning for possible cardiac allograft rejection. Rejection may present subtly — heart failure symptoms, new arrhythmia, fatigue, or hemodynamic instability. The denervated heart may not produce typical anginal symptoms even with significant pathology.
Transplant cardiology consulted emergently regarding need for endomyocardial biopsy and adjustment of immunosuppression. Disposition: Admit.
Clinical Education
The Denervated Heart
The transplanted heart has no autonomic innervation. Resting heart rate is higher (90–110 bpm), and there is no vagal response to stimuli. This fundamental difference shapes ED management in several critical ways.[2]
Atropine is useless — there is no vagal tone to block. Adenosine should be given at half dose (3 mg initial) because the denervated heart has increased adenosine receptor sensitivity. Exercise tolerance is altered — the heart relies on circulating catecholamines rather than direct sympathetic input, so the response to exercise is delayed and blunted.
Silent ischemia is a real risk. The transplanted heart may not present with typical chest pain during ACS. Have a low threshold for workup when any concerning features are present.
Cardiac Allograft Vasculopathy
Accelerated diffuse atherosclerosis affecting up to 70% of transplant patients.[1] Usually presents after the first year post-transplant. Often asymptomatic due to denervation — may present as heart failure, new arrhythmia, or sudden death rather than angina.
Pathophysiology combines immune-mediated injury and traditional atherosclerotic risk factors. Annual surveillance with coronary angiography is standard. Treatment options: surgical revascularization or re-transplantation.
Dysrhythmia Management
| Arrhythmia | Frequency | Key Points |
| PVCs/PACs | Most common | Usually benign, no treatment needed |
| RBBB | 2nd most common | From surgical trauma, typically stable |
| Bradycardia | 3rd most common | SA/AV node dysfunction; epinephrine or isoproterenol — NOT atropine |
| AFib/AFlutter | 4th most common | Concerning for rejection; high mortality; avoid CCBs |
| SVT | Less common | Half-dose adenosine (3 mg) |
Drug Interactions with Immunosuppressants
Calcineurin inhibitors (cyclosporine, tacrolimus) are metabolized by CYP3A4 and interact with many common medications.[3]
AVOID: Calcium channel blockers (diltiazem, verapamil), macrolide antibiotics, azole antifungals, and amiodarone — all increase calcineurin inhibitor levels and risk toxicity.
Safe rate control alternatives: Beta-blockers, though response may be blunted in the denervated heart.
Immunosuppressant side effects to monitor: Hyperkalemia, hypomagnesemia, nephrotoxicity, new-onset diabetes. Corticosteroid complications include osteoporosis, avascular necrosis, tendon rupture (Achilles, quadriceps), and glucose intolerance.
Acute Rejection
Can occur at any time but most common in the first year. May present as heart failure, new arrhythmia (especially atrial fibrillation), fatigue, or hemodynamic instability. The denervated heart does not produce typical anginal symptoms, making rejection harder to recognize.[5]
Endomyocardial biopsy is the gold standard for diagnosis. Hyperacute rejection occurs minutes to hours post-transplant (ABO incompatibility). Acute cellular rejection develops over weeks to months. Antibody-mediated rejection may be more insidious. The ED role: recognize concerning features, stabilize, consult transplant cardiology emergently.
References
- Lund LH et al. The Registry of the International Society for Heart and Lung Transplantation: Thirty-fourth adult heart transplantation report. J Heart Lung Transplant. 2017;36(10):1037-1079. PubMed
- Costanzo MR et al. The International Society of Heart and Lung Transplantation Guidelines for the care of heart transplant recipients. J Heart Lung Transplant. 2010;29(8):914-956. PubMed
- Mangini S et al. Heart transplantation: review. Einstein (São Paulo). 2015;13(2):310-318. PubMed
- Patel JK, Bhatt AN. Cardiac allograft vasculopathy: current concepts. Curr Opin Cardiol. 2020;35(3):283-288.
- Colvin M et al. OPTN/SRTR 2018 Annual Data Report: Heart. Am J Transplant. 2020;20(S1):340-426. PubMed
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