End stage heart failure requiring Left Ventricle Assist Device in a patient with Thyrotoxicosis
Shahana Shahid and Diana Saez Garcia, Transplant Unit, Harefield Hospital.
A 19 year old male patient presented with a two week history of worsening shortness of breath, orthopnea and pedal oedema associated with vomiting, anorexia and weight loss. He reported a four year history of intermittent palpitations, pedal oedema and reduced exercise tolerance which had not previously been investigated. Examination findings included pulmonary oedema, raised JVP, hepatomegaly and bilateral leg oedema. Investigations revealed thrombocytopenia, hyponatraemia, an ALT of 1566 IU/L, Bilirubin 66umol/L, TSH 0.06 IU/L and free T4 47.6 pmol/L. An echocardiogram showed a severely dilated and thin walled left ventricle with severely impaired systolic function (Ejection Fraction 17%). His viral cardiomyopathy screen was negative. A Technitium scan showed florid homogenous uptake typical of Grave’s disease and thyroid peroxidase antibodies were also positive.
After 10 days of ward based care with heart failure medication, Milrinone and GTN infusion as well as carbimazole and beta-blockers for hyperthyroidism, he required transfer to ITU for further haemodynamic deterioration. He was started on inotropic support with Adrenaline and mechanical support with an intraaortic balloon pump (IABP). However, despite normalisation of thyroid biochemistry, after 30 days of support he still remained balloon pump dependent.
A CircuLite Synergy partial support Left Ventricle Assist Device (LVAD) was implanted through a small right-sided thoracotomy. However, the patient remained Adrenaline and IABP dependent with severe biventricular failure and it was decided to upgrade the device to a full support LVAD (Heartware, HVAD). The patient had an uneventful postoperative period and was discharge to the ward on the 7th postoperative day.
Approximately 6% of patients with hyperthyroidism present with congestive heart failure. It is felt that this is most often a rate-related cardiomyopathy which is resolved once euthyroid state is reached, only less than 1% of patients develop persistent dilated cardiomyopathy (1).
Given the 4 year history of cardiac symptoms and the presence of a thin walled left ventricle on echocardiography it was felt that the patient had an underlying cardiomyopathy. Severe thyrotoxicosis probably accounted for an acute severe decompensation in cardiac function.
1. Dahl P, Danzi S, Klein I (2008) Thyrotoxic Cardiac Disease. Current Heart Failure Reports 5/3(170-6)