Detailed clinical, physiological and pathological phenotyping can impact access to disease-modifying treatments in ATTR carriers.

BACKGROUND: Hereditary transthyretin amyloidosis is a life-threatening autosomal dominant systemic disease due to pathogenic TTR variants (ATTRv), mostly affecting the peripheral nerves and heart. The disease is characterised by a combination of symptoms, organ involvement and histological amyloid deposition. The available disease-modifying ATTRv treatments (DMTs) are more effective if initiated early. Pathological nerve conduction studies (NCS) results are the cornerstone of large-fibre polyneuropathy diagnosis, but this anomaly occurs late in the disease. We investigated the utility of a multimodal neurological and cardiac evaluation for detecting early disease onset in ATTRv carriers. METHODS: We retrospectively analysed a cohort of ATTRv carriers with normal NCS results regardless of symptoms. Multimodal denervation and infiltration evaluations included a clinical questionnaire (Lauria and New York Heart Association (NYHA)) and examination, intra-epidermal nerve fibre density assessment, autonomic assessment based on heart rate variability, Sudoscan, meta-iodo-benzyl-guanidine scintigraphy, cardiac biomarkers, echocardiography, MRI and searches for amyloidosis on skin biopsy and bone scintigraphy. RESULTS: We included 130 ATTRv carriers (40.8% men, age: 43.6±13.5 years), with 18 amyloidogenic TTR gene mutations, the majority of which was the late-onset Val30Met variant (42.3%). Amyloidosis was detected in 16.9% of mutation carriers, including 9 (6.9%) with overt disease (Lauria>2 or NYHA>1) and 13 asymptomatic carriers (10%) with organ involvement (small-fibre neuropathy or cardiomyopathy). Most of these patients received DMT. Abnormal test results of unknown significance were obtained for 105 carriers (80.8%). Investigations were normal in only three carriers (2.3%). CONCLUSIONS: Multimodal neurological and cardiac investigation of TTRv carriers is crucial for the early detection of ATTRv amyloidosis and initiation of DMT.

Skin amyloid deposits and nerve fiber loss as markers of neuropathy onset and progression in hereditary transthyretin amyloidosis.

BACKGROUND AND PURPOSE: This study was undertaken to assess skin biopsy as a marker of disease onset and severity in hereditary transthyretin amyloidosis with polyneuropathy (ATTRv-PN), a treatable disease. METHODS: In this single center retrospective study, skin Congo red staining and intraepidermal nerve fiber density (IENFD) were evaluated in symptomatic ATTRv-PN patients and asymptomatic TTR gene mutation carriers between 2012 and 2019. Non-ATTRv subjects with suspected small fiber neuropathy who underwent skin biopsy during the same timespan were used as controls. RESULTS: One hundred eighty-three symptomatic ATTRv-PN patients, 36 asymptomatic carriers, and 537 non-ATTRv patients were included. Skin biopsy demonstrated amyloid depositions in 80% of the 183 symptomatic cases. Skin amyloid deposits were found in 75% of early stage ATTRv-PN patients, and in 14% of asymptomatic carriers. All 183 symptomatic and 34 of 36 asymptomatic patients displayed decreased ankle IENFD with a proximal-distal gradient distribution, and reduced IEFND correlated with disease severity and duration. CONCLUSIONS: Our study demonstrates skin amyloid deposits are a marker of ATTRv-PN disease onset, and decreased IENFD a marker of disease progression. These results are of major importance for the early identification of ATTRv-PN patients in need of disease-modifying treatments.

What is the lowest change in cardiac output that transthoracic echocardiography can detect?

BACKGROUND: In critically ill patients, changes in the velocity-time integral (VTI) of the left ventricular outflow tract, measured by transthoracic echocardiography (TTE), are often used to non-invasively assess the response to fluid administration or for performing tests assessing fluid responsiveness. However, the precision of TTE measurements has not yet been investigated in such patients. First, we aimed at assessing how many measurements should be averaged within one TTE examination to reach a sufficient precision for various variables. Second, we aimed at identifying the least significant change (LSC) of these variables between successive TTE examinations. METHODS: We prospectively included 100 haemodynamically stable patients in whom TTE examination was planned. Three TTE examinations were performed, the first and the third by one operator and the second by another one. We calculated the precision and LSC (1) within one examination depending on the number of averaged measurements and (2) between measurements performed in two successive examinations. RESULTS: In patients in sinus rhythm, averaging three measurements within an examination was enough for obtaining an acceptable precision (interquartile range highest value < 10%) for VTI. In patients with atrial fibrillation, averaging five measurements was necessary. The precision of some other common TTE variables depending on the number of measurements is provided. Between two successive examinations performed by the same operator, the LSC was 11 [5-18]% for VTI. If two operators performed the examinations, the LSC for VTI significantly increased to 14 [8-26]%. The LSC between two examinations for other TTE variables is also provided. CONCLUSIONS: Averaging three measurements within one TTE examination is enough for obtaining precise measurements for VTI in patients in sinus rhythm but not in patients with atrial fibrillation. Between two TTE examinations performed by the same operator, the LSC of VTI is compatible with the assessment of the effects of a 500-mL fluid infusion but is not precise enough for assessing the effects of some tests predicting preload responsiveness.

A Clinical and Echocardiographic Score to Identify Pulmonary Hypertension Due to HFpEF.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a frequent cause of pulmonary hypertension (PH) that is not easy to differentiate from precapillary PH. We aimed to determine whether the characteristic features of the patients may help differentiate between HFpEF and precapillary PH. METHODS AND RESULTS: Clinical and echocardiographic parameters were analyzed in 156 patients referred to our PH referral center. Right heart catheterization identified 78 PH-HFpEF patients and 78 with precapillary PH. Compared with precapillary PH, PH-HFpEF patients were older, with a smaller proportion of women, a higher proportion of hypertension, diabetes mellitus, atrial fibrillation and sleep apnea syndrome, and a higher body mass index. On echocardiography, PH-HFpEF patients had higher left ventricular mass index, higher left atrial area, and smaller right ventricular end-diastolic area. Following multivariate analysis, a model predicting the probability of PH-HFpEF was built with history of diabetes mellitus, presence of atrial fibrillation, left atrial area, right ventricular end-diastolic area, and left ventricular mass index. The score was internally validated using bootstrap method (area under the curve 0.93 [95% confidence interval 0.918-0.938]). A score <5 ruled out PH-HFpEF. CONCLUSION: A score including clinical and echocardiographic criteria may help physicians to identify PH-HFpEF from precapillary PH.

Comparison between tafamidis and liver transplantation as first-line therapy for hereditary transthyretin amyloidosis.

BACKGROUND: By stabilizing transthyretin, tafamidis delays progression of amyloidosis due to transthyretin variant (ATTRv) and replaced liver transplantation (LT) as the first-line therapy. No study compared these two therapeutic strategies. METHODS: In a monocentric retrospective cohort analysis, patients with ATTRv amyloidosis treated with either tafamidis or LT were compared using a propensity score and a competing risk analysis for three endpoints: all-cause mortality, cardiac worsening (heart failure or cardiovascular death) and neurological worsening (worsening in PolyNeuropathy Disability score). RESULTS: 345 patients treated with tafamidis (n = 129) or LT (n = 216) were analyzed, and 144 patients were matched (72 patients in each group, median age 54 years, 60% carrying the V30M mutation, 81% of stage I, 69% with cardiac involvement, median follow-up: 68 months). Patients treated with tafamidis had longer survival than LT patients (HR: 0.35; p = .032). Conversely, they also presented a 3.0-fold higher risk of cardiac worsening and a 7.1-fold higher risk of neurological worsening (p = .0071 and p < .0001 respectively). CONCLUSIONS: ATTRv amyloidosis patients treated with tafamidis would present a better survival but also a faster deterioration of their cardiac and neurological statuses as compared with LT. Further studies are needed to clarify the therapeutic strategy in ATTRv amyloidosis.

Associations between ocular and extra-ocular assessment in primary Sjögren's syndrome.

OBJECTIVES: To assess associations between ophthalmological features and the main systemic biomarkers of primary Sjögren's Syndrome (pSS), and to identify systemic biomarkers associated with severe keratoconjunctivitis sicca (KCS) in pSS patients. METHODS: In this cross-sectional study, data was retrospectively extracted from the monocentric cohort of the French reference centre for pSS. We analysed data from the initial visit of patients admitted for suspicion of pSS and included patients validating pSS ACR/EULAR classification criteria. Ophthalmological assessment included Schirmer's test, tear break-up time, ocular staining score (OSS), and visual analogue scale (DED-VAS) for dry eye disease (DED) symptoms. Results of minor salivary gland biopsy, unstimulated whole salivary flow rate, anti-SSA/Ro antibodies, anti-SSB/La antibodies, and rheumatoid factor (RF) were collected. RESULTS: A total of 253 patients (245 females) with confirmed pSS, aged 56.6±13.0 years, were included, among which 37% had severe KCS. Multivariate analysis showed that the presence of anti-SSA/Ro antibodies, anti-SSB/La antibodies and RF were associated with conjunctival OSS (odds ratio-OR-=1.25 per OSS unit increase; confidence interval-CI-95%=1.05-1.49; P=0.01; OR=1.31 per OSS unit increase; CI95%=1.09-1.58, P=0.002, and OR=1.34 per OSS unit increase; CI95%=1.12-1.59; P=0.001, respectively). Both anti-SSB/La antibodies and DED-VAS ≥ 5 were significantly associated with severe KCS (OR=2.03; CI95%=1.03-4.00; P<0.05 and OR=2.52, CI95%=1.31-4.90; P<0.01, respectively). CONCLUSION: Association between conjunctival OSS and systemic biomarkers of pSS indicate the crucial importance of conjunctival staining when pSS is suspected as a cause of DED. Conversely, patients with anti-SSB and DED-VAS ≥ 5 features should be prioritized for extensive evaluation by an ophthalmologist due to their association with severe KCS.

Cause of death analysis and temporal trends in survival after liver transplantation for transthyretin familial amyloid polyneuropathy.

BACKGROUND: Hereditary transthyretin amyloidosis (ATTR) is a multisystemic disease involving mainly the peripheral nervous system and the heart. Liver transplantation (LT) is the reference treatment for ATTR neuropathy and preoperative detection of high risk patients is crucial. We aimed to document the causes of death of ATTR patients after LT, their temporal trends, and to evaluate whether the available preoperative tools that predict the risk of death after LT for hereditary ATTR amyloidosis matched with these trends. METHODS: A retrospective longitudinal cohort study was performed on 215 consecutive ATTR patients who underwent LT between January 1993 and January 2011. Each patient's death cause and timing were classified. RESULTS: Over a median follow up of 5.9 years, 84 patients died. The rate of death was higher in the first year following LT than thereafter (13.0 vs. 4.3 ± 1.8%/year; p = .004). Cardiac events ranked as the leading cause of death (C: 38%), followed by infections (I: 24%), graft complications (G: 17%), end stage amyloidosis, stroke and others (ASO: 7% each). Deaths due to graft complications and infections (GI) occurred earlier than those due to end stage amyloidosis and stroke. Death prediction was less accurate for GI-related mortality than for other causes, which blunted the accuracy of the early-term risk prediction scores. Conclusions In ATTR amyloidosis, cardiac events were the leading cause of death after liver transplantation. Close preoperative evaluation allowed for accurate mid-term prediction of mortality, but the high rate of graft complications and infections blunted the early-term risk prediction.

Potential Role of In Vivo Confocal Microscopy for Imaging Corneal Nerves in Transthyretin Familial Amyloid Polyneuropathy.

IMPORTANCE: Small fiber neuropathy (SFN) is an important feature of transthyretin familial amyloid polyneuropathy (TTR-FAP). A practical and objective method for the clinical evaluation of SFN is needed to improve the management of this disease. In vivo confocal microscopy (IVCM) of the corneal nerves, a rapid noninvasive technique, may be used as a surrogate marker of SFN. OBJECTIVE: To determine the correlation of SFN with IVCM in patients with TTR-FAP. DESIGN, SETTING, AND PARTICIPANTS: A prospective, single-center, cross-sectional controlled study was conducted at the French National Reference Center for TTR-FAP from June 1, 2013, to June 30, 2014. Fifteen patients with TTR-FAP underwent a complete neurologic examination, including Neuropathy Impairment Score of the Lower Limbs, hand grip strength, and evaluation of vegetative dysfunction, as well as electrophysiologic studies (nerve conduction and electrochemical skin conductance) and intraepidermal nerve fiber density quantification. Patients and 15 controls (matched for age and sex) underwent ophthalmologic assessments, including corneal esthesiometry and IVCM. MAIN OUTCOMES AND MEASURES: Correlation of corneal nerve fiber length (CNFL) with the severity of SFN. RESULTS: Of the 15 patients enrolled in the study, 6 were women (40%); mean (SD) age was 54.4 [13.7] years. The CNFL was shorter in the patients than in controls (13.08 vs 17.57 mm/mm2; difference of 4.49 [95% CI, 0.72 to 8.27]; P = .02). The patients' CNFL correlated with the severity of both autonomic neuropathy assessed by the Compound Autonomic Dysfunction Test (rs = 0.66 [95% CI, 0.22 to 0.87]; P = .008) or electrochemical skin conductance (rs = 0.80 [95% CI, 0.50 to 0.93]; P < .001) and sensorimotor neuropathy assessed using the Neuropathy Impairment Score of the Lower Limbs (rs = -0.58 [95% CI, -0.84 to -0.11]; P = .02). Patients with altered sensory nerve action potentials and intraepidermal nerve fiber density had a shorter CNFL (P = .04 and P = .02, respectively). The CNFL could be measured in all patients compared with sensory nerve action potentials (11 patients [73%; 95% CI, 44% to 92%]; P < .001) and intraepidermal nerve fiber density (4 patients [27%; 95% CI, 8% to 55%]; P < .001). CONCLUSIONS AND RELEVANCE: In these 15 patients with TTR-FAP, IVCM measurement permitted rapid, noninvasive evaluation of small-fiber alterations in patients and could be used to assess SFN in this setting. The CNFL could be measured in all patients, thus avoiding the floor effect seen with other neuropathy measures. Longitudinal studies with more cases evaluated are needed to define the place of IVCM in monitoring patients with TTR-FAP.

Cardiac Dysautonomia Predicts Long-Term Survival in Hereditary Transthyretin Amyloidosis After Liver Transplantation.

OBJECTIVES: This study sought to compare techniques evaluating cardiac dysautonomia and predicting the risk of death of patients with hereditary transthyretin amyloidosis (mATTR) after liver transplantation (LT). BACKGROUND: mATTR is a multisystemic disease involving mainly the heart and the peripheral nervous system. LT is the reference treatment, and pre-operative detection of high-risk patients is critical. Cardiovascular dysautonomia is commonly encountered in ATTR and may affect patient outcome, although it is not known yet which technique should be used in the field to evaluate it. METHODS: In a series of 215 consecutive mATTR patients who underwent LT, cardiac dysautonomia was assessed by a dedicated clinical score, time-domain heart rate variability, 123-meta-iodobenzylguanidine heart/mediastinum (123-MIBG H/M) ratio on scintigraphy, and heart rate response to atropine (HRRA). RESULTS: Patient median age was 43 years, 62% were male and 69% carried the Val30Met mutation. Cardiac dysautonomia was documented by at least 1 technique for all patients but 6 (97%). In univariate analysis, clinical score, 123-MIBG H/M ratio and HRRA were associated with mortality but not heart rate variability. The 123-MIBG H/M ratio and HRRA had greater area under the curve (AUC) of receiver-operating characteristic curves than clinical score and heart rate variability (AUC: 0.787, 0.748, 0.656, and 0.523, respectively). Multivariate score models were then built using the following variables: New York Heart Association functional class, interventricular septum thickness, and either 123-MIBG H/M ratio (SMIBG) or HRRA (Satropine). AUC of SMIBG and Satropine were greater than AUC of univariate models, although nonsignificantly (AUC: 0.798 and 0.799, respectively). Predictive powers of SMIBG, Satropine, and a reference clinical model (AUC: 0.785) were similar. CONCLUSIONS: Evaluation of cardiac dysautonomia is a valuable addition for predicting survival of mATTR patients following LT. Among the different techniques that evaluate cardiac dysautonomia, 123-MIBG scintigraphy and heart rate response to atropine had better prognostic accuracy. Multivariate models did not improve significantly prediction of outcome.