Size matters - redefining sex differences among patients with transthyretin amyloid cardiomyopathy – have we been wrong all along?

Background

Transthyretin amyloid cardiomyopathy (ATTR-CM) is most often diagnosed in men (1–5). The few available studies suggest affected women have a more favourable cardiac phenotype (5–8), but remain unclear regarding differences in outcomes.

Objectives and methods

To characterise sex differences among consecutive patients with non-hereditary and two prevalent forms of hereditary ATTR-CM diagnosed over a 20-year period at our specialist centre through analysis of deep phenotyping at presentation, changes on serial echocardiography and overall prognosis.

Results

In total, 1732 patients were studied, comprising: 1095 with wild-type (wt)ATTR-CM; 206 with T60A-hATTR-CM; and 431 with V122I-hATTR-CM. Female prevalence was greater in T60A-hATTR-CM (29.6%) and V122I-hATTR-CM (27.8%) compared to wtATTR-CM (6%). At presentation, females were 3.3 years older than males (81.9 vs 77.8 years for wtATTR-CM; 68.7 vs 65.1 years for T60A-hATTR-CM; 77.1 vs 74.9 years for V122I-hATTR-CM). At diagnosis, non-indexed measures of wall thickness were significantly greater in males (interventricular septum in diastole (IVSd) of 17.13mm in males & 16.15mm in females; p<0.001). When indexed for body surface area (BSA), we observed that the mean indexed IVSd was fairly constant in males throughout the study period, but in females, had a tendency to decrease over the same study period. Furthermore, BSA significantly influenced measures of disease severity. When indexed for BSA, overall structural and functional phenotype was similar between sexes; the few observed significant differences including indexed IVSd (9.62mm/m2 in females & 8.88mm/m2 in males; p<0.001), indexed left ventricular (LV) end-diastolic volume (35.07ml/m2 in females & 41.05ml/m2 in males; p<0.001) and indexed LV end-systolic volume (17.95ml/m2 in females & 21.74ml/m2 in males; p<0.001) suggested a mildly worse phenotype in females. No significant differences were observed in disease progression on serial echocardiography and mortality across the overall population (p=0.459) and when divided by genotype (p=0.730 for wtATTR-CM; p=0.161 for T60A-hATTR-CM; p=0.056 for V122I-hATTR-CM).

Conclusion

This study of a well-characterized large cohort of ATTR-CM patients, contrary to previous dogmas, did not demonstrate overall differences between sexes in either clinical phenotype, when indexed, or with respect to disease progression and prognosis. The analysis highlighted the deficiencies in using non-indexed values which can not only lead to the inaccurate perception of a milder clinical phenotype in women compared to men, but has been shown to result in female patients presenting at an older age and with a worse phenotype compared to men. These findings indicate the need for revision of existing clinical guidelines regarding awareness and diagnosis of ATTR-CM in women, and modification of clinical trials which currently use single non-indexed threshold for wall thickness as key inclusion criterion.

Funding Acknowledgement

Type of funding sources: Foundation.

Myocardial ischaemia in cardiac amyloidosis: a change of perspective

Introduction

Cardiac involvement is the main driver of clinical outcomes in systemic amyloidosis; however many clinical observations are not explained by the concept of replacement of the interstitium by amyloid material. Preliminary studies support the hypothesis that myocardial ischaemia contributes to cellular damage.

Purpose

This study assesses the presence and mechanisms of myocardial ischaemia using cardiovascular magnetic resonance (CMR) with multiparametric mapping and histopathological assessment.

Methods

Ninety-two patients with cardiac amyloidosis (CA) (AL = 41, ATTR = 51) and 97 without CA (3-vessel coronary disease (3VD) = 47, unobstructed coronary arteries = 26, healthy volunteers (HV) = 24) underwent quantitative stress perfusion CMR with myocardial blood flow (MBF) mapping. Twenty-six myocardial biopsies and 3 explanted hearts with CA were analysed histopathologically.

Results

Stress MBF was severely reduced in patients with CA with lower values than patients with 3VD, unobstructed coronary arteries and HV (CA = 1.03±0.51 ml/min/g, 3VD = 1.35±0.50 ml/min/g, Unobstructed coronaries = 2.92±0.52 ml/min/g, HV = 3.14±0.69 ml/min/g; CA vs 3VD p=0.008, CA vs Unobstructed coronaries p<0.001, CA vs HV p<0.001). After adjustment for intracellular volume the MBF in patients with CA remained significantly lower than in HV (stress MBF/ICV: AL = 2.24±1.12, ATTR = 2.22±0.93, HV = 4.38±1.06; AL vs. ATTR p=1.000, AL vs HV p<0.001, ATTR vs. HV p<0.001). Myocardial perfusion reserve (MPR) was severely reduced in CA patients, compared to HV and patients with unobstructed coronary arteries, with the degree of reduction being comparable only to patients with 3VD (CA = 1.55±0.60, 3VD = 1.54±0.51, unobstructed coronaries = 2.78±0.70, HV = 4.08±0.86; CA vs 3VD p=1.000, CA vs unobstructed coronary arteries p<0.001, CA vs. HV p<0.001). Myocardial perfusion abnormalities correlated with amyloid burden, systolic and diastolic function, structural parameters and blood biomarkers (p<0.05). Biopsies demonstrated diffuse hypoxia with abnormal VEGF staining in cardiomyocytes and endothelial cells. Amyloid infiltration in intramural arteries was associated with severe lumen reduction in 20% of vessels, and severe reduction in capillary density.

Conclusion

CA is associated with severe myocardial ischaemia demonstrable by histology and CMR stress perfusion mapping. Histological evaluation indicates a complex pathophysiology, where systolic and diastolic dysfunction, amyloid infiltration of the epicardial arteries and disruption and rarefaction of the capillaries play a role in contributing to myocardial ischaemia.

Funding Acknowledgement

Type of funding sources: None.

Changes in referral pathway and phenotypic status of patients diagnosed with ATTR cardiac amyloidosis during the past 20 years

Background

Diagnostic and therapeutic advances have led to much increased awareness of transthyretin (ATTR) cardiac amyloidosis (CA).

Purpose

We sought to characterise the impact of this on referral practice, cardiac phenotype at diagnosis and specifically to determine whether patients are now being diagnosed at an earlier stage in their disease process.

Methods

We studied 1845 patients diagnosed with ATTR-CA at the National Amyloidosis Centre (NAC) from 2002–2021, all of whom underwent deep clinical phenotyping and follow-up.

Results

Analysis by 5-year quartiles revealed a substantial incremental increase in patients diagnosed with ATTR-CA (35 vs 260 vs 704 vs 846), which was associated with greater proportions of patients referred following advanced cardiac imaging (referrals following cardiac magnetic resonance and bone scintigraphy: 3% vs 44% vs 67% vs 76%; P<0.001). Over time, median duration of symptoms prior to diagnosis diminished from 36-months between 2002–2006 to 12-months between 2017–2021 (P<0.001) and a greater proportion of patients presented with milder disease across the 5-yearly quartiles (NAC stage 1: 40% vs 43% vs 44% vs 57%; P<0.001). The latter was associated with more favourable echocardiographic parameters of structure and function, including an incremental reduction in maximal left ventricular wall thickness (18.26mm vs 17.41mm vs 17.09mm vs 16.68mm; P=0.017). This was associated with improved survival in the overall population (2007–2011 vs 2012–2016: HR=1.65, 95% CI [1.33–2.06]; P<0.001 and 2012–2016 vs 2017–2021: HR =1.83, 95% CI [1.45–2.31]; P<0.001) and in each genotype (wtATTR, T60A and V122I). Despite a significant increase in the proportion of patients enrolled into clinical trials (0.0% vs 0.0% vs 2.6% vs 23.9%; P<0.001) and prescribed disease modifying therapy (5.7% vs 0.4% vs 4.8% vs 13.5%; P<0.001); the improved survival remained significant even after adjusting for clinical trials and disease modifying therapy (2012–2016 vs. 2017–2021: HR=1.65 95% CI [1.29–2.11], P<0.001).

Conclusion

Increased awareness and advances in cardiac imaging have been associated with a substantial increase in the diagnosis of ATTR-CA and at a progressively earlier stage of the disease, which has contributed to improved survival in recent years. These changes may have important implications for initiation and outcome of therapy. Given that ATTR-CA is now being diagnosed earlier, more data are needed to guide decisions on in whom and when to initiate treatment, and which treatments should be used at each disease stage. Furthermore, the changes in ATTR-CA phenotype at diagnosis urgently need to be factored into clinical trial design, given that pre-determined end-points based on trials performed in the past may no longer be appropriate, or at least sufficiently powered, or of adequate duration to evaluate efficacy of novel agents.

Funding Acknowledgement

Type of funding sources: None.

A multi-modality, multi-parametric phenotyping study of transthyretin amyloid cardiomyopathy associated with the p.V142I TTR variant

Introduction

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an increasingly recognised cause of heart failure. 3–4% of individuals of African descent carry a transthyretin gene mutation encoding the p.V142I variant, a powerful risk factor for development of variant ATTR-CM. This equates to 1.6 million potential carriers in the USA alone. We report findings from a multi-parametric, multi-modality phenotyping study of p.V142I ATTR-CM.

Hypothesis

The phenotype of p.V142I variant ATTR-CM is an aggressive form of ATTR CM.

Methods

A retrospective phenotyping study of 395 patients with p.V142I-ATTR-CM at our national referral centre was conducted. Patients underwent evaluation at the centre at time of diagnosis, including clinical and functional assessment, echocardiography, biomarker analysis; a subgroup had cardiac magnetic resonance imaging. 395 wild type ATTR-CM patients matched for independent predictors of prognosis (NAC Disease Stage, age, decade of first presentation) were used as a comparator group.

Results

Average age of pV142I ATTR-CM patients was 75.8 years. There was significant functional impairment (38.2% of cases NHYA ≥ III, mean 6 minute walk test distance 272m). Significant impairment of echocardiographic parameters was seen; mean LVEF 43%, global longitudinal strain −9.1%, TAPSE 14.2mm, E/E prime 17.4, E/A ratio 2.47 with high frequency of at least moderate mitral (44%) and tricuspid regurgitation (51%). Median NT-proBNP was 3165 ng/L (IQR 4224). Arrhythmias were common with 17.4% of patients having a bradyarrhythmia, 26.1% having atrial fibrillation/flutter, and 5.6% having a pacemaker at presentation. Uni and multivariate cox regression analysis identified serum troponin, tricuspid regurgitation, LVEF, TAPSE and lower systolic blood pressure as independent predictors of prognosis. Prognostic parameters were statistically significantly worse and five year survival by Kaplan Meier analysis was significantly reduced when compared to matched WT ATTR-CM patients (p<0.05) (Figure 1).

Mean serum high sensitivity troponin T and extracellular volume (ECV) by cardiac magnetic resonance (CMR) was higher in p.V142I ATTR-CM than WT ATTR-CM cases (94 ng/L vs 74.2 ng/L, p<0.05, 58% vs 55%, p<0.05). Interventricular wall thickness however was lower in p.V142I ATTR-CM than matched WT cases (17.2 mm vs 16.8 mm).

Conclusion

p.V142I ATTR-CM is an aggressive phenotype, with significant functional impairment, burden of regurgitant valvular disease and systolic impairment resulting in poor survival.

Patients with p.V142I ATTR-CM had a higher burden of amyloid infiltration as measured as shown by ECV measurements on CMR, higher serum troponin and lower wall thickness when compared to a matched cohort of WT ATTR-CM patients. This novel observation suggests a unique disease mechanism that is more cardiotoxic which results in myocyte loss and myocardial thinning as opposed to myocyte hypertrophy.

Funding Acknowledgement

Type of funding sources: None.

Progression, regression and redefining the treatment response – cardiac magnetic resonance with T1 and extracellular volume mapping in cardiac light-chain amyloidosis

Background

The presence and severity of cardiac involvement in AL amyloidosis is the main driver of prognosis [1]; patients with symptomatic heart failure frequently die within 6 months [1] but median survival has nearly doubled over the past decade, mainly due to significant improvements in chemotherapy. The haematological response to chemotherapy is principally evaluated with serial measurements of serum-free light-chains (FLC) [2]. The cardiac response to chemotherapy is assessed through changes in serum concentrations of brain natriuretic peptides (including NT-proBNP) and echocardiographic parameters [3–5]. Neither are able to directly measure cardiac amyloid burden. Cardiovascular magnetic resonance (CMR) with extra-cellular volume (ECV) mapping can measure the extent cardiac amyloid infiltration [6].

Aims

We investigated the ability of CMR to: 1) measure changes in response to chemotherapy; 2) assess the correlation between haematological response (HMR) and changes in cardiac amyloid; 3) assess the association between changes in cardiac amyloid and prognosis over and above existing predictors.

Methods

In total, 176 patients with cardiac light-chain amyloidosis treated with chemotherapy were assessed with FLC, NT-proBNP and CMR with ECV mapping at baseline (before chemotherapy), 6-months, 12-months & 24-months after commencing chemotherapy. Haematological response was categorized by reductions in FLC as: complete response (CR), very good partial response (VGPR), partial response (PR) or no response (NR). CMR response was categorized by changes in ECV as: progression (≥0.05 increase), stable (<0.05 change) or regression (≥0.05 decrease).

Results

A progressive increase in patients achieving either CR or VGPR was observed at each time point (61% of patients at 6-months, 71% at 12-months and 80% at 24-months). At 6-months, CMR regression was observed in 3% (all had either CR or VGPR) and progression in 32% (61% had either PR or NR; 39% had either CR or VGPR). At 1-year, CMR regression was observed in 22% (all had either CR or VGPR); progression in 22% (63% had either PR or NR; 37% had either CR or VGPR). At 2-years, CMR regression was observed in 38% (all had CR/VGPR); progression in 14% (80% had either PR or NR; 20% had either CR or VGPR). During follow-up (40±15 months), 36 (25%) patients died. CMR response at 6-months predicted death (progression HR 3.821; 95% CI 1.950–7.487; p<0.001) and remained independently associated with prognosis after adjusting for haematological response, NT-proBNP and longitudinal strain on echocardiography (p<0.01).

Conclusions

CMR demonstrates that cardiac amyloid deposits frequently regress following chemotherapy, but only in patients who achieve CR or VGPR, highlighting the need for deep haematological response. Changes in amyloid burden (ECV) predict outcomes after adjusting for known predictors, showing the crucial role of CMR in redefining treatment response.

Funding Acknowledgement

Type of funding sources: Foundation.

Multi-imaging characterisation of cardiac phenotype in different types of amyloidosis

Background

Bone scintigraphy is extremely valuable when assessing patients with suspected cardiac amyloidosis (CA), but the clinical significance and associated phenotype of different degrees of myocardial tracer uptake across different types of amyloidosis is yet to be defined.

Purpose

We sought to define the phenotypes of patients with varying degrees of cardiac uptake on bone scintigraphy, across multiple types of systemic amyloidosis using extensive characterisation comprising of biomarkers, echocardiographic and cardiac magnetic resonance (CMR) imaging.

Methods

A total of 296 patients (117 immunoglobulin light-chain [AL] amyloidosis, 165 transthyretin [ATTR] amyloidosis, 7 apolipoprotein-A1-amyloidosis [AApoAI],and 7 apolipoprotein-A4-amyloidosis [AApoA4]) underwent deep characterisation of their cardiac phenotype.

Results

AL-amyloidosis patients with grade 0 myocardial radiotracer uptake spanned the spectrum of CMR findings from no evidence of CA to characteristic features of CA, while AL-amyloidosis patients with grade 1–3 always produced characteristic CMR features. In ATTR-amyloidosis the CA burden strongly correlated with myocardial tracer uptake (correlation between bone scintigraphy cardiac uptake and CMR derived extracellular volume: R=0.88, 95% CI [0.84–0.91], P<0.001), except in patients with the Ser77Tyr variant. AApoAI-amyloidosis presented with grade 0–1 myocardial tracer uptake, and unique features of disproportionate right sided involvement such as disproportionate right ventricular (RV) and right atrial uptake on bone scintigraphy, RV free wall thickening, and tricuspid valve thickening and dysfunction. Within our cohort, AApoAIV-amyloidosis always presented with grade 0 myocardial tracer uptake, and characteristic features of CA on CMR. All AL-amyloidosis patients with grade 1 myocardial tracer uptake had characteristic CMR features of CA (n=48, 100%), while only ATTR-amyloidosis grade 1 patients with the Ser77Tyr variant had characteristic features of CA on CMR (n=5, 11.4%). Following the exclusion of Ser77Tyr and AApoAI, a CMR showing characteristic features of CA or an extracellular volume >0.40 in a patient with grade 1 myocardial tracer uptake had a sensitivity and specificity of 100% for diagnosing AL-amyloidosis.

Conclusion

Deep characterisation of the cardiac phenotype in different types of amyloidosis, across a range of bone scintigraphy cardiac uptake grades has identified clear differences between each amyloidosis type. The distinctive characteristics in each cohort has allowed the development of a diagnostic pathway to help define the diagnostic differentials and the clinical phenotype in each individual patient, following comprehensive assessment with bone scintigraphy and CMR.

Funding Acknowledgement

Type of funding sources: None.

Physico-chemical properties of cervical mucus discharge and endocrine profile during oestrus and metoestrus period in crossbred dairy cows with and without metoestrual bleeding

The physicochemical properties of cervical mucus discharge (CMD), serum oestrogen and progesterone profiles during oestrus (day 0) and metoestrus (day 2) period in crossbred cows with (Group I, n=12) and without (Group II, n=12) history of profuse metoestrual bleeding were studied. Majority of group I cows exhibited clear and transparent CMD (83.33 per cent) with thin consistency (100 per cent), typical fern pattern (83.33 per cent), pH (7.58±0.12) and spinnbarkeit value of 12.64±0.50 cm during oestrus. However, during metoestrus all the cows (100 per cent) exhibited bloody CMD with thin consistency (66.67 per cent), ‘nil’ fern pattern (0.0 per cent), mean pH of 7.96±0.10 and mean spinnbarkeit value of 9.35±0.5 cm. In group I cows, the mean pH and spinnbarkeit values of CMD (7.96±0.10 and 9.35±0.5 cm, respectively) was significantly (p<0.01) higher than that of group II cows (7.64±0.07 and 7.75±0.30 cm, respectively) during metoestrus. The mean serum progesterone concentration of group I cows (1.61±0.55 ng/mL) was significantly (p<0.05) higher than that of group II cows (0.36±0.07 ng/mL) on day of oestrus. The mean serum oestradiol concentration of group I cow (6.85±0.53 pg/mL) was significantly (p<0.05) lower when compared to group II cows (8.48±0.49 pg/mL) during metoestrus. In conclusion, the physicochemical properties of CMD, serum progesterone and oestrogen profiles significantly altered in group I cows during oestrus and metoestrus which showed lower conception rate than that of group II cows.

Clinical importance of left atrial infiltration in cardiac transthyretin amyloidosis

Funding Acknowledgements

Type of funding sources: None.

INTRODUCTION

 The clinical significance of left atrial (LA) involvement in ATTR amyloidosis cardiomyopathy (ATTR-CM) has not been characterized. The aims of this study were to characterize: (1)LA pathology in explanted ATTR-CM hearts; (2)LA mechanics using echocardiographic speckle-tracking in a large cohort of ATTR-CM patients; (3)to study the association with mortality.

METHODS AND RESULTS

Congo red staining and immunohistochemistry was performed to assess the presence, type and extent of amyloid and associated changes in 5 explanted ATTR-CM atria. Echo speckle-tracking was used to assess LA reservoir, conduit, contractile function and stiffness in 906 ATTR-CM patients (551 wt-ATTR-CM;93 T60A-ATTR-CM;241 V122I-ATTR-CM;21 other).

There was extensive ATTR amyloid infiltration in the 5 atria with loss of normal architecture, vessels remodelling, capillary disruption and subendocardial fibrosis. Echo speckle-tracking in 906 ATTR-CM patients demonstrated increased atrial stiffness [median(25th-75th quartile) 1.83(1.15-2.92)] that remained independently associated with prognosis, after adjusting for known predictors (lnLA stiff:HR = 1.26,CI 1.07-1.57;p = 0.009). There was substantial impairment of the three phasic functional atrial components [reservoir 8.86(5.94-12.97)%; conduit 6.5(4.53-9.28)%; contraction function 4.0(2.29-6.56)%]. Atrial contraction was absent in 21.6% of patients whose ECG showed sinus rhythm (SR)-"atrial electro-mechanical dissociation"(AEMD). AEMD was associated with poorer prognosis compared to SR patients with effective mechanical contraction (p &lt; 0.0001). AEMD conferred a similar prognosis to patients in AF.

CONCLUSION

The phenotype of ATTR-CM includes significant infiltration of the atrial walls with progressive loss of atrial function and increased stiffness, which is a strong independent predictor of mortality. AEMD emerged as a distinctive phenotype identifying patients in SR with poor prognosis.

Abstract Figure.

Regression of cardiac amyloid deposits with novel therapeutics: reaching new frontiers in cardiac ATTR amyloidosis

Background

Cardiac involvement is the main driver of outcome in ATTR amyloidosis. Advances in therapeutics hold potential in transforming the course of the disease but the impact on cardiac amyloid load is unknown. The aim of this study was to evaluate the impact of patisiran, a new double stranded RNA based gene silencing therapy and a stabilizer, diflunisal, on cardiac amyloid load as measured by CMR and T1 mapping, in patients with ATTR amyloidosis.

Methods and results

Thirty-two patients with hereditary cardiac amyloidosis were studied. Sixteen patients received treatment with patisiran, and sixteen control subjects did not receive any disease modifying treatment. Patients were assessed with echocardiogram, CMR, NT-proBNP and six-minute walk time measurements at baseline and at 1 year (Mean interval 11.45±3.08 months in treatment group, mean interval 12.82±5.06 months in the control group). CMR analysis comprised LV volumes, T1 mapping to measure the extracellular volume (ECV) occupied by amyloid, T2 mapping and late gadolinium enhancement imaging. At 1-year follow-up, there was a substantial reduction in cardiac amyloid burden, in keeping with cardiac amyloid regression in 45% of patients on treatment. Overall the treatment group showed a reduction in ECV at 1 year follow up compared to an increase in ECV at 1 year in the control group (−1.37%, 95% CI: −3.43 to 0.68% versus 5.02%, 95% CI: 2.86% to 7.18% respectively, p&lt;0.001). The treatment group also showed an improvement in change in 6MWT at 1 year follow up compared to 6MWT at 1 year in the control group (−8.12 meters, 95% CI: −50.8 to 34.6 meters in the treatment group versus −132.27 meters, 95% CI: −216 to −48.6 meters in the control group, p=0.002). The treatment group showed a reduction in BNP at 1 year follow up compared to an increase in the control group (−567.87, 95% CI: −1288.90 to 153.15 in the treatment group versus 2004, 95% CI: 12.82 to 3995.45 in the control group, p&lt;0.001). There was no significant difference from baseline and 1-year data between the control and treatment groups for the difference in echocardiographic parameters, native T1, T2. There was a significant reduction in the percentage of injected dose by 99Tc-DPD scintigraphy in treated patients at 1 year compared to baseline.

Conclusions

These findings provide the first compelling evidence of substantial cardiac amyloid regression in ATTR amyloidosis, as well as the potential for CMR to be used to track response in treated patients with ATTR cardiac amyloidosis. Combination therapy with transthyretin knock down and stabilizing agents may well be synergistic given enhanced stoichiometry of stabilizers in the face of much reduced plasma transthyretin concentration.

Funding Acknowledgement

Type of funding source: None

Atrial strain in cardiacATTR amyloidosis from pathophysiology to prognosis: is it time to rethink our approach to disease?

Background

Left atrial (LA) involvement in cardiac ATTR amyloidosis (ATTR-CM) has never being explored. The aim of the study is to characterize the spectrum of changes in LA structure in ATTR-CM, the functional consequences on LA mechanics and the association with mortality.

Methods

We studied 936 patients with ATTR-CM who underwent prospective protocolized evaluations comprising ECG, full echocardiographic assessment, 6MWT, blood biomarkers sampling and survival assessment between 2000 and 2019. Reservoir (LAr), conduit (LAcd) and booster (LAcont) function were assessed according to current guidelines. LA stiffness (LAstiff) was estimated as the ratio between E/e' and LAr. The presence and extent of amyloid infiltration was assessed in two autopsied hearts from patients ATTR-CM with congo red staining and TTR antibodies.

Results

936 patients with ATTR-CM were included, 567 with wtATTR-CM and 346 with hATTR-CM, of whom 246 had the V122I variant and 100 the T60A variant. LA indexed area was similar across the 3 genotypes, whilst LAr, LAcd and LAcont were significantly reduced in V122I patients compared to Wt and T60A patients (LAr: 10.4±6.4 vs 12.8±8.5 vs 8.59±5.7%, p&lt;0.0001; LAcd: 5.6±5.0 vs 6.9±5.7 vs 4.0±3.6%, p&lt;0.0001; LAcont 7.5±4.1 vs 8.2±4.9 vs 6.7±4.2%, p=0.023; in Wt, T60 and V122I respectively). Similarly, LAstiff was significantly worse in V122I compared to Wt and T60A (LAstiff: 2.39±2.62 vs 2.59±4.83 vs 2.96±2.88, p&lt;0.0001, in Wt, T60 and V122I respectively). In the overall population, LAstiff remained independently associated with mortality, after adjusting for rhythm, systolic and diastolic functional parameters, ventricular longitudinal strain, genotypes, clinical variables and NAC staging system (lnLA stiff: HR=1.26, CI: 1.07–1.57; p=0.009). In the overall population, 584 patients were in sinus rhythm and 344 in atrial fibrillation, atrial flutter or atrial tachycardia (non-sinus rhythm group – NSR). Among patients in SR, 21.6% did not show a measurable LA mechanical contraction on strain analysis (LAcont). Patients in SR without LAcont on strain analysis showed similar structural and functional LA changes, NTproBNP, NYHA class, and 6MWT to NSR patients. Mortality of patients in SR with no LAcont was significantly reduced compared to patients in SR with LAcont and similar to patients in AF (Figure 1). On the two autopsies hearts there was extensive amyloid infiltration of TTR type in the atrial wall as confirmed with CR and TTR antibodies (Figure 1).

Conclusions

ATTR-CM is characterized by primary infiltration of the atrial walls with progressive loss of atrial function and increased stiffness. LA stiffness is a strong independent predictor of mortality after adjusting for known predictors. Atrial electro-mechanical dissociation emerged as a distinctive functional phenotype identifying patients in SR with worse prognosis.

Figure 1

Funding Acknowledgement

Type of funding source: None

Comparison of Factors Identified by Patients and Physicians Associated with Hospital Readmission (COMPARE2)

OBJECTIVE

Factors contributing to hospital readmission have rarely been sought from the patient perspective. Furthermore, it is unclear how patients and physicians compare in identifying factors contributing to readmission. The objective of the study was to identify and compare factors contributing to hospital readmission identified by patients and physicians by surveying participants upon hospital readmission to a teaching medicine service.

METHODS

Patients 18 years and older who were discharged and readmitted to the same service within 30 days and the physicians caring for these patients were surveyed to identify factors contributing to readmission. Secondary outcomes included comparing responses between groups and determining level of agreement. Patients could be surveyed multiple times on subsequent readmissions; physicians could be surveyed for multiple patients.

RESULTS

A total of 131 patients and 37 physicians were consented. The mean patient age was 60.1 years (standard deviation 16.8 years) and 55.6% were female; 56.4% were white, and 42.1% were black/African American. In total, 179 patient surveys identified "multiple medical problems" (48.6%), "trouble completing daily activities" (45.8%), and "discharged too soon" (43.6%) most frequently as contributing factors; 231 physician surveys identified "multiple medical problems" (45.0%) and "medical condition too difficult to care for at home" (35.6%) most frequently as contributing factors. Paired survey results were available for 135 readmissions and showed fair agreement for only 1 factor but no agreement for 5 factors.

CONCLUSIONS

Patients identified previously unknown factors contributing to readmission. Little agreement existed between patients and physicians. Additional research is needed to determine how best to address patient-identified factors contributing to readmission.

1171Myocardial perfusion mapping in cardiac amyloidosis - exploring the spectrum from infiltration to ischaemia

Background

Cardiac involvement is the main driver of outcome in systemic amyloidosis, but the relationship between amyloid deposits and outcomes is not well understood. The simple explanation of physical, mechanical replacement of the interstitium by amyloid seems insufficient. Preliminary studies support the hypothesis that myocardial ischaemia could contribute to cell damage.

Purpose

(1) To assess myocardial ischaemia in cardiac amyloidosis. (2) To compare patients with cardiac amyloidosis to patients assessed on invasive coronary angiography (ICA) to have normal coronary physiology (NCP), microvascular dysfunction (MVD) and triple vessel coronary disease (3VD). (3) To assess correlation of perfusion mapping to markers of disease severity and prognosis.

Methods

86 patients and 20 healthy volunteers (HV) underwent CMR at 1.5T (Siemens) with standard cine, PSIR-LGE, T1, T2, Extracellular Volume (ECV) mapping and adenosine stress with myocardial blood flow (MBF) mapping. Thirty-eight patients also underwent ICA with 3 vessel assessment of Index of Microcirculatory Resistance and Fractional Flow Reserve: 7 had cardiac amyloidosis, 8 had NCP, 15 had MVD and 8 had 3VD.

Results

Cardiac amyloidosis patients had severe reduction in stress MBF and myocardial perfusion reserve (MPR) (1.22ml/g/min±0.70 and 1.62±0.63) compared to HV (3.21ml/g/min±0.64, p<0.001 and 4.17±0.78, p<0.001), NCP (2.66±0.56, p<0.001 and 2.51±0.43, p=0.036) and MVD (2.10±0.31, p<0.001 and 2.29±0.87, p=0.014) with the degree of reduction being similar only to patients with 3VD (1.44±0.54, p=1.000 and 1.64±0.68, p=1.000) (Figure 1). Rest MBF was also lower in amyloidosis than HV. Cardiac amyloidosis stress MBF and MPR inversely correlated with amyloid burden (ECV, r=−0.715, p<0.001, transmurality of LGE, p<0.01), systolic dysfunction (EF, r=0.405, p<0.01), and blood biomarkers (NT-proBNP (r=−0.678, p<0.001) and Troponin T (r=−0.628, p<0.001)). There was a correlation between stress MBF and native T1 (r=−0.588, p<0.001) but not T2 (p=0.591). Stress MBF and MPR were early disease markers, being elevated in patients with early cardiac amyloid infiltration (raised ECV, no LGE, P<0.01 vs HV).

Conclusion

Myocardial ischaemia is common in cardiac amyloidosis – with stress MBF and MPR similar to that of patients with 3VD. The reduction correlates with the degree of amyloid infiltration and markers of adverse prognosis, highlighting the potential role of myocardial ischaemia as a key mechanism in the pathophysiology of cardiac amyloidosis.

Comparative evaluation of pain, tenderness and swelling followed by radiographic evaluation of periapical changes at various intervals of time following single and multiple visit endodontic therapy: an in vivo study

AIM

This clinical study was undertaken to evaluate the postoperative sequelae following single-visit versus multiplevisit endodontic therapy at various interval of time in vital as well as nonvital teeth.

MATERIALS AND METHODS

Thirty-two cases were randomly assigned to the following four groups, group I, group II, group III and group IV. After gaining the access to the pulp chamber, establishing the working length , thorough cleaning and shaping was done for all the cases. Obturation was done by protaper (variable taper) gutta-percha and AH-PLUS sealer using lateral and vertical condensation technique. All the cases were recalled after 48 hours, 1 week, 4 weeks and 6 weeks following obturation and were evaluated for postoperative pain, tenderness and swelling.

RESULTS

There was no statistically significant difference amongst all the four groups in the incidence and severity of postoperative pain, tenderness and swelling at the end of one week. However, within 48 hours groups I, II and IV showed more pain when compared to group III. And groups I, II and III showed more tenderness compared with groups IV. Postoperative swelling was not reported. Radiographic investigation at the end of 6 weeks showed significant change in the appearance of the periapical region in group II and group IV cases.

CONCLUSION

On strict adherence to biological principles and proper case selection, no significant difference in the success, postoperative pain and tenderness exist when treated with either single-visit or multiple-visit therapy.

CLINICAL SIGNIFICANCE

No significant difference in the success rate or postoperative pain, tenderness, and swelling exists when treated with either single-visit or multiple-visit endodontic therapy. Hence, one can readily integrate one-visit endodontic therapy into the routine clinical practice of dentistry.