Describing circadian blood pressure profile in patients with hereditary transthyretin amyloidosis and asymptomatic mutation carriers

<h3>Introduction</h3> Hereditary or variant transthyretin amyloidosis (ATTRv) is a life-threatening disease with new disease modifying treatments. Cardiovascular autonomic failure is a key feature. Abnormal circadian blood pressure (BP) rhythm might represent a risk factor for cardiovascular events. This study evaluates BP profile in ATTRv patients and carriers. <h3>Methods</h3> 97 patients with ATTRv and 12 <i>TTR</i> mutation carriers underwent ambulatory 24h BP measurements (ABPM; 29%F, mean age 58y, 43% T60A mutation). Dipping profile was defined according to the consensus criteria. Autonomic function testing (AFT) included tilt table/standing/pressor tests, heart rate responses to Valsalva Manoeuvre and deep breathing. <h3>Results</h3> 54/97 patients were on treatment affecting BP, carriers had no relevant treatments. 74/109 subjects showed an abnormal dipping profile (53 reduced dipping, 21 non-/reversed dipping). 4/74 subjects were carriers (all reduced dippers): three had mild AFT impairment, one was normal. 6/8 carriers with normal ABPM showed abnormal AFT. <h3>Conclusion</h3> Pathologic BP profiles are common in ATTRv and may be an early feature in carriers. Both ABPM and AFT are needed to detect subtle autonomic impairment. ABPM is a useful screening tool but does not allow for quantitative assessment requiring AFT. Longitudinal studies are needed to investigate changes in circadian rhythm.