Outcome of exercise electrocardiography in familial amyloidotic polyneuropathy patients, Portuguese type, under evaluation for liver transplantation

Familial amyloidotic polyneuropathy (FAP) is a dominantly inherited systemic amyloidosis caused by mutated transthyretin (TTR). Liver transplantation is currently the only available treatment that halts the progress of the disease. Cardiovascular complications are common in FAP, and cardiac arrhythmias are typical complications in FAP Val130Met. For patients with late onset FAP, as the Swedish patients, coronary heart disease has been found in several patients, and a QS complex is not an uncommon finding in FAP-patients ECG raising the suspicion of coronary heart disease. The aim of this study was to evaluate exercise ECG in FAP patients before transplantation with regard to mortality and morbidity. Thirty-eight FAP patients who underwent examination by exercise ECG, as part of the evaluation for liver transplantation were included in the study. Of these, 30 patients were transplanted, and the surviving patients were followed for at least 2 years. Exercise ECG was performed on bicycles with standard 12 leads. Nonparametric statistical analyses were used in all calculations. Six patients died 0-5.5 years after transplantation. They were older than the survivors (p < 0.01), but their duration of disease did not deviate from that of survivors (p = 0.8). They were also less able to increase their heart rates during exercise than the survivors (p < 0.05). For all transplanted patients, a significant relationship was found between patients' increase of heart rate, blood pressure and maximal workload, and the duration of disease and also for the PND-score, signifying that the outcome of exercise ECG predominantly was related to the patients autonomic and motor function, and not to their heart function.