Total intravenous anesthesia for cardiac transplantation in a teenager with Becker muscular dystrophy: A case report

Abstract

Becker muscular dystrophy (BMD) is a genetic disorder caused by partial deficiency of dystrophin, leading to progressive skeletal muscle weakness and cardiac failure. Up to one-third of affected individuals develop dilated cardiomyopathy, eventually requiring heart transplantation at a young age. Although BMD is not directly linked to malignant hyperthermia (MH), patients may experience severe MH-like reactions, particularly when exposed to succinylcholine or volatile anesthetics. Therefore, total intravenous anesthesia (TIVA) is often preferred in this population, despite the cardioprotective benefits of volatile agents through myocardial preconditioning. We report the case of a teenager with BMD and advanced cardiomyopathy who successfully underwent heart transplantation under TIVA. Anesthesia was maintained with target-controlled infusion (TCI) of propofol and remifentanil. Additional boluses of ketamine and midazolam were administered to maintain a bispectral index (BIS) between 40 and 60. Postoperatively, the patient was admitted to the intensive care unit receiving low-dose infusions of dobutamine, sodium nitroprusside, and inhaled nitric oxide, and was safely extubated 3 h later. This case highlights the feasibility and safety of TIVA in patients with BMD undergoing major cardiac surgery.

Introduction

Becker muscular dystrophy (BMD) is an inherited disorder that leads to progressive muscle weakness, associated with respiratory and cardiac failure, eventually requiring cardiac transplantation in young adults.[1] Patients with BMD present an increased risk of anesthesia-related complications, including malignant hyperthermia (MH)-like episodes, which pose significant challenges for anesthetic management, particularly during high-risk surgical procedures.[2]This case report describes the successful use of total intravenous anesthesia (TIVA) in a teenager with BMD undergoing cardiac transplantation.

Case Presentation

A 15-year-old male patient, 54 kg, was admitted for a heart transplantation due to dilated cardiomyopathy secondary to BMD. The dystrophinopathy was diagnosed at the age of 3 during an evaluation for muscular weakness, and severe cardiomyopathy was subsequently identified at the age of 14. A previous echocardiogram revealed a 12% left ventricular ejection fraction, pulmonary hypertension, and systolic dysfunction.

The anesthesia machine was prepared by removing vaporizers and high-flow oxygen ventilation before the patient entered the operating room. The patient was monitored with electrocardiography, invasive blood pressure, body temperature, oximetry, and bispectral index (BIS). He was receiving continuous infusion of dobutamine at a rate of 7.5 μg/kg/min in a central line. General anesthesia was performed with remifentanil, etomidate, lidocaine, ketamine, midazolam, and rocuronium and maintained with remifentanil at 0.1 μg/kg/min. Propofol was administered via target-controlled infusion (TCI) using the Schnider model, with an effect-site target ranging from 1.0 to 1.8 μg/mL throughout the intraoperative period. The depth of anesthesia was carefully monitored with BIS. Inhaled nitric oxide was initiated at 30 ppm.

A developed supraventricular tachycardia was promptly treated with synchronized electrical cardioversion. Dobutamine was reinitiated at 15 μg/kg/min and gradually tapered to 5 μg/kg/min by the end of the procedure, in conjunction with inhaled nitric oxide at 10 ppm. A sodium nitroprusside infusion was initiated at 0.3 μg/kg/min. The effect of heparin was reversed with protamine sulfate. The total duration of cardiopulmonary bypass (CPB) was 90 min, and the cold ischemic time was 118 min.

Laboratory examinations at the end of the surgery showed an arterial pH of 7.23, bicarbonate 17.8 mEq/L, lactate 1.56 mmol/L, and central venous oxygen saturation (SvcO2) 82%. He received a total amount of 8 g of epsilon-aminocaproic, one prothrombin complex concentrate, and 360 mL of autologous blood retrieved by the cell saver device. The patient was transferred to the intensive care unit (ICU) and was safely extubated 3 h later. He was discharged from the ICU five days later.

Discussion

BMD is an X-linked recessive disorder affecting approximately 1 in 18,000 male births and is characterized by progressive skeletal muscle weakness. It results from mutations in the same gene implicated in Duchenne muscular dystrophy (DMD) but leads to a reduced quantity or truncated form of the dystrophin protein, in contrast to the complete absence of dystrophin observed in DMD. Up to one-third of patients develop dilated cardiomyopathy requiring advanced therapies such as heart transplantation, and nearly all individuals with BMD will exhibit some degree of cardiac dysfunction over the course of the disease.[3]

Furthermore, patients with BMD are not truly predisposed to MH, but rather to MH-like reactions, particularly anesthesia-induced rhabdomyolysis (AIR). Although previously considered at risk for MH, current evidence indicates that several neuromuscular disorders—including BMD and DMD—are instead associated with AIR, a distinct clinical entity.[1]AIR typically occurs in response to succinylcholine and, to a lesser extent, volatile anesthetics. Unlike MH, which is a hypermetabolic crisis characterized by increased oxygen consumption, carbon dioxide production, and responsiveness to dantrolene, AIR presents with acute rhabdomyolysis and severe hyperkalemia that may lead to cardiac arrest, often without changes in oxygen saturation or metabolic rate.[2]Its management relies on supportive measures and avoidance of triggering agents.[4] The distinction between MH and AIR is critical, as it influences both anesthetic planning and emergency treatment strategies in patients with dystrophinopathies.

Therefore, the American Academy of Pediatrics recommended the use of TIVA in patients with neuromuscular disorders, due to the risk of severe hyperthermic episodes and AIR associated with volatile anesthetics and succinylcholine.[5,6]In alignment with these guidelines, TIVA was employed in the present case.

It should be noted that volatile anesthetics have been associated with theoretical advantages in cardiac surgery, referred to as myocardial preconditioning. These agents have been shown to reduce myocardial injury biomarkers and decrease infarct size in animal models.[7]Although there are no prospective studies comparing TIVA and balanced inhalation anesthesia in the context of cardiac transplantation, available evidence supports the safety and efficacy of TIVA using TCI of propofol and remifentanil in elective cardiac surgeries involving CBP. A large, randomized, multicenter trial involving patients undergoing coronary artery bypass grafting found no significant differences in 30-day or 1-year all-cause mortality between TIVA and balanced anesthesia. Secondary outcomes, including myocardial infarction, hospital readmission, and ICU length of stay were also comparable between the two groups.[8]Another randomized trial comparing TIVA or balanced anesthesia showed no differences in postoperative opioid consumption, time to extubation, or length of hospital stay.[9] We have also found one case report of heart transplantation using TIVA with propofol and remifentanil. The patient remained hemodynamically stable and was extubated immediately after the procedure.[10]

This case also reinforces the importance of multidisciplinary coordination in the perioperative management of patients with neuromuscular disorders, particularly those undergoing complex procedures such as cardiac transplantation. Anesthetic decisions must consider not only the underlying myopathy but also potential cardiac involvement and the risk of life-threatening complications such as hyperkalemia and rhabdomyolysis.

As a limitation, this report reflects a single clinical experience and, therefore, cannot be generalized to all patients with BMD. Larger studies or case series are needed to better define the anesthetic management and outcomes in this specific subgroup undergoing cardiac transplantation. In conclusion, the present case highlights the importance of careful anesthetic planning in patients with BMD undergoing high-risk cardiac procedures such as transplantation. While TIVA appears to be an effective approach in such contexts, further research is warranted to clarify its comparative advantages in cardiac transplant patients.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.