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Contributor: Travis Barlock, MD Educational Pearls: -
Key clinical considerations when managing heart transplant patients due to their unique pathophysiology -
1. Arrhythmias -
A transplanted heart is denervated, meaning it lacks autonomic nervous system innervation -
The lack of vagal tone results in an increased resting heart rate -
Adenosine can be used since it primarily slows conduction through the AV node -
Atropine is ineffective in treating transplant bradyarrhythmia because its mechanism is to inhibit the vagus nerve - but the heart lacks vagal tone -
Allograft rejection can also cause tachycardia -
2. Rejection -
Transplant patients are administered immunosuppressants -
Clinical presentation of acute rejection looks similar to heart failure with increased BNP, increased troponin, and pulmonary edema -
Cardiac allograft vasculopathy is a form of chronic rejection -
Patients will not report chest pain due to denervated heart -
3. High risk of infection due to immunosuppression -
Increased risk of infections which includes CMV, legionella, tuberculosis, etc -
Immunosuppressants have side effects such as acute kidney injury or pancytopenia -
4. Radiographic Cardiomegaly -
A study found that radiographic cardiomegaly does not connote heart failure -
They hypothesized it is instead the result of a mismatch between the size of the transplanted heart and the space in the thoracic cavity References -
Murphy JD, Mergo PJ, Taylor HM, Fields R, Mills RM Jr. Significance of radiographic cardiomegaly in orthotopic heart transplant recipients. AJR Am J Roentgenol. 1998 Aug;171(2):371-4. doi: 10.2214/ajr.171.2.9694454. PMID: 9694454. -
Park MH, Starling RC, Ratliff NB, McCarthy PM, Smedira NS, Pelegrin D, Young JB. Oral steroid pulse without taper for the treatment of asymptomatic moderate cardiac allograft rejection. J Heart Lung Transplant. 1999 Dec;18(12):1224-7. doi: 10.1016/s1053-2498(99)00098-4. PMID: 10612382. -
Pethig K, Heublein B, Wahlers T, Dannenberg O, Oppelt P, Haverich A. Mycophenolate mofetil for secondary prevention of cardiac allograft vasculopathy: influence on inflammation and progression of intimal hyperplasia. J Heart Lung Transplant. 2004 Jan;23(1):61-6. doi: 10.1016/s1053-2498(03)00097-4. PMID: 14734128. Summarized by Meg Joyce, MS1 | Edited by Meg Joyce & Jorge Chalit, OMS3 Donate: https://emergencymedicalminute.org/donate/ |