Cardiac transplantation and ventricular assist devices — structured clinical encounter

Station brief (candidate)

You are the paediatric registrar in a tertiary paediatric cardiac centre. A four-month-old infant with a known idiopathic dilated cardiomyopathy and an ejection fraction of 18 percent is on a loop diuretic, an ACE inhibitor and caloric supplementation. Over two weeks the tachypnoea has worsened, feeds take 40 minutes with sweating, the weight has crossed two centiles downward, and the creatinine has begun to rise. The advanced heart-failure team is being consulted. The team asks you to establish that the failure is refractory, to discuss the device pathway, and to begin the family counselling. You have 12 minutes with the team and 5 minutes for examiner discussion. [6]

Information available on request

• Four-month-old term infant, known idiopathic dilated cardiomyopathy, ejection fraction 18 percent on the most recent echocardiogram. [4]
• Current therapy: loop diuretic, ACE inhibitor, caloric supplementation; no inotropes; no arrhythmia on monitoring. [6]
• Two-week trajectory: worsening tachypnoea, feeds taking 40 minutes with sweating, weight crossing two centiles downward, creatinine rising from baseline. [6]
• Examination (on request): gallop rhythm, displaced apex, hepatomegaly 4 cm below the costal margin, cool peripheries with capillary refill 3 seconds; saturations 96 percent in air; femoral pulses present and symmetric. [6]
• Echocardiogram (on request): dilated thin-walled left ventricle, ejection fraction 17 percent, moderate mitral regurgitation, no intracardiac thrombus, pulmonary artery pressure estimate at the upper limit of normal. [4]
• Cardiac catheterisation (on request): pulmonary vascular resistance at the upper limit of normal, below the transplant-contraindication threshold; no structural obstruction. [4]

Tasks

1. Establish that this infant has refractory heart failure and grade the urgency with the INTERMACS profile. [6]
2. State the most likely durable device and the evidence that supports it, and explain why the device choice depends on the size of the child. [1]
3. State the strategic goal of the device and the prerequisites for transplant listing in this child. [4]
4. Name the leading complications of the device and the surveillance they require. [10]
5. Begin counselling the parents on what the device and the transplant pathway will mean. [4]

Marking anchors

Must-hit

• Recognises refractory heart failure — progressive signs and emerging end-organ dysfunction (rising creatinine) despite maximal guideline medical therapy — and grades the child as INTERMACS profile 2 or 3 (declining or stable inotrope-dependent), framing the urgency. [6]
• Selects the durable paracorporeal pulsatile Berlin Heart EXCOR as the device for an infant of this size, citing the Almond 2013 cohort that established its bridge-to-transplant role, and explains that device choice is governed by the size of the child. [1]
• States the strategic goal as bridge to transplantation, and the prerequisites for listing: exclusion of a reversible cause (notably a tachycardia-induced cardiomyopathy) and a pulmonary vascular resistance below the transplant-contraindication threshold on catheterisation. [4]

Merit

• Names stroke as the dominant VAD complication and a leading cause of death on support, with mandatory anticoagulation and serial neurological surveillance, and describes the family-counselling balance between device risk and the goal of transplanting the child in the best possible condition. [10]

Fail

• Recommends indefinite ECMO without defining an exit strategy, or lists for transplantation without excluding a reversible cause or measuring the pulmonary vascular resistance. [4]
• Counsels the parents that the device is a cure or that transplantation needs no lifelong follow-up, against the reality of lifelong immunosuppression and surveillance. [4]