Perioperative management of the heterotopic heart transplant recipient for catheter abalation of native heart ventricular tachycardia

Abstract

Introduction Heterotopic heart transplant is a surgical procedure whereby the donor heart is grafted onto the native heart in parallel and essentially behaving as a biventricular support system for the native heart. This technique allowed for smaller donor hearts to be used and appeared to be advantageous in the pre-cyclosporine era as those who went on to suffer primary graft failure still had some residual cardiac output from the native heart. This is rarely performed these days and survivor numbers are diminishing, but it is still possible to encounter such patients as they present with coronary artery disease, valvular disease or dysrhythmias in either the native or donor heart, in addition to illnesses unrelated to their transplant. Results A 56-year-old male presented to our hospital with palpitations, chest discomfort and dyspnoea 21 years after heterotopic heart transplant for non-ischaemic dilated cardiomyopathy (DCM). ECG confirmed ventricular tachycardia (VT) in the native heart and although initial cardioversion was successful, the VT returned and proved to be refractory to cardioversion and medical anti-arrhythmic therapies. Coronary angiography and cardiac MRI excluded ischaemia as a cause for the dysrhythmia and he eventually underwent cardiac catheter electrophysiology mapping and subsequent radiofrequency ablation of both left and right ventricles including outflow tracts of the native heart. Challenges of delivering anaesthesia in the cardiac catheter laboratory include its remote location, risk risks of radiation, the ergonomics of positioning (and access to) the patient in an environment that does not lend itself to complex cardiac anaesthesia. Present in this case was the additional aspect of anaesthetising a heart transplant recipient. Issues relate to both the transplanted heart and the ever-present complications of immunosuppressant drug regimes. These include the pathophysiological consequences of a denneravated heart (though in this case most likely to be partially re-innervated) and numerous complex medical co-morbidities including significant renal impairment. The anaesthetic monitoring required is invariably intricate and must include multimodal ECG, transoesophageal echocardiography and invasive pressure measurement. Cardiovascular instability must be expected at any point during general anaesthesia and extreme vigilance is require from all involved in its delivery. Discussion The principles of the perioperative management of orthoptic cardiac transplant recipients apply those with heterotopic grafts. As clinical experience of heterotopic recipients declines, unfamiliarity of the heterotopic transplant circulation is not the only challenge in the management of such patients. Performing and interpreting many of the usual haemodynamic monitoring techniques available to the cardiac anaesthetist (such as electrocardiography, transthoracic and transoesophageal echocardiogram, invasive cardiac output monitors) may prove to be difficult.