Carpal tunnel syndrome and spinal canal stenosis: harbingers of transthyretin amyloid cardiomyopathy?

Abstract

BackgroundCarpal tunnel syndrome (CTS) and spinal canal stenosis can be frequently observed in the medical history of patients with transthyretin amyloidosis (ATTR), both in the hereditary (mt-ATTR) and wild-type (wt-ATTR) form. The aim of this retrospective single-center analysis was to determine the prevalence of these findings, delay to diagnosis of systemic amyloidosis and the prognostic value in a large cohort of patients with wt-ATTR and mt-ATTR amyloidosis.MethodsMedical records of 253 patients diagnosed with wt-ATTR, 136 patients with mt-ATTR and 77 asymptomatic gene carriers were screened for history of CTS and spinal canal stenosis and laboratory analysis, electrocardiography and echocardiographic results, respectively. Clinical follow-up was performed by phone assessment.ResultsHistory of CTS was present in 77 patients (56%) with mt-ATTR, in 152 patients (60%) with wt-ATTR and even in 10 of the asymptomatic gene carriers (13%). Latency between carpal tunnel surgery and first diagnosis of systemic amyloidosis was significantly longer in wt-ATTR compared to mt-ATTR (117\xa0±\xa0179 months vs. 66\xa0±\xa073 months; p\u2009=\u20090.02). In total, 36 patients (14%) with wt-ATTR and 7 patients (5%) with mt-ATTR had a history of clinically significant spinal canal stenosis. In the subgroup of mt-ATTR, patients with CTS had thicker IVS (19\xa0±\xa05\xa0mm vs. 16\xa0±\xa05\xa0mm, p\u2009<\u20090.05), higher LV mass index (225\xa0±\xa078\xa0g vs. 193\xa0±\xa098\xa0g, p\u2009<\u20090.05), lower Karnofsky index (78\xa0±\xa015% vs. 83\xa0±\xa017%, p\u2009<\u20090.05), and lower mitral annular plane systolic excursion (MAPSE; 9\xa0±\xa04\xa0mm vs. 11\xa0±\xa05\xa0mm, p\u2009<\u20090.05) compared to patients without CTS, whereas in wt-ATTR no significant differences could be observed. No significant difference in survival was observed between patients with and without CTS (wt-ATTR: 67 vs. 63 months, p\u2009=\u20090.45; mt-ATTR: 74 vs. 63 months, p\u2009=\u20090.60). A combination of CTS and spinal stenosis was present in 32 wt-ATTR patients (12%) and 3 mt-ATTR patients (2.2%).ConclusionsThe prevalence of CTS is high and the latency between CTS surgery and diagnosis of amyloidosis is long among patients with wt-ATTR and mt-ATTR. CTS might be predictive for future occurrence of systemic (predominantly cardiac) ATTR amyloidosis.