Citations

Abstract Background: Amyloidosis is a multisystem disease with extracellular deposition of pathological insoluble beta-fibrillar proteins. Involvement of the heart is seen in more than one-half of the patients with systemic AL amyloidosis and it is the most important determinant of clinical outcome. Cardiac amyloidosis is a restrictive infiltrative cardiomyopathy in which, despite declines in stroke volume that accompany disease progression, the ejection fraction (EF) often remains preserved even in advanced stages of the disease. King et al. proposed a novel index of myocardial function, the myocardial contraction fraction (MCF), defined as the ratio of stroke volume (SV) to myocardial volume (MV). MCF is a measure of myocardial shortening, which differentiated myocardial performance in patients with similar degrees of hypertrophy and in a recent small cohort of AL amyloidosis patients appeared superior to left ventricular ejection fraction (EF) in predicting overall survival (OS). It was our goal to assess the prognostic role of MCF in a large cohort of patients with AL amyloidosis in the context of other prognostic variables. Methods: Patients seen between 4/1/1999 and 2/1/2015 were eligible for this retrospective study if they had an ECHO at the Mayo Clinic, Rochester, MN within 30 days of their AL amyloidosis diagnosis with measurements of left ventricular chamber size and wall thickness needed to calculate MCF, EF, and the presence or absence of pericardial effusion. To capture the full cohort, modeling was done first excluding Mayo (2012) staging and global averaged left ventricular longitudinal peak systolic strain (LV strain) since limited numbers of patients had these studies, 342 and 294, respectively. Thresholds of continuous variables were chosen based on receiver operator curves targeting death at 1-year. Cox proportional hazards analysis was used to identify factors that were prognostic for OS. Statistical analyses were done using JMP 9.0 (SAS, Cary, NC). Results: Among the 722 patients satisfying entry criteria,median age was 64 years (range 32-94) and 66% were male. The best cutoff for MCF was 21% (sensitivity: 74%, specificity: 60%; AUC=0.699) and distinguished two groups with different OS (median 53 vs. 9 months, P<0.0001; Figure). On univariate analysis the baseline ECHO variables predicting OS were interventricular septum thickness (IVS) >12 mm (RR 1.8, P=0.0002), EF <60% (RR 1.7), MCF ≤21% (RR 2.1), and presence of pericardial effusion (RR 2.0), all with P<0.0001. On multivariate MCF ≤21% (RR 1.6, P <0.0001), EF <60% (RR 1.4, P=0.0007) and the presence of pericardial effusion (RR 1.3, P=0.002) were independent predictors of OS. Additional modeling was done with the subset of 342 patients who were assessable for Mayo (2012) staging, (i.e. measurements of immunoglobulin free light chain, NT-proBNP, and troponin T). On univariate analysis, patients with a Mayo (2012) stage ≥ 3 had a RR 2.1, p<0.0001. On multivariate, only MCF ≤21% (RR 1.5, P =0.01), Mayo (2012) stage ≥ 3 (RR 1.5, P=0.01) and EF<60% (RR 1.7, P=0.0006) were independent prognostic determinants. Finally, we addressed LV-strain among the 294 patients in whom the study was performed. There was a significant correlation between MCF and LV strain (rho =-0.86, P<0.0001). On univariate, LV-strain less negative than -13 generated a RR of 2.3, p<0.0001. In contrast to the model containing MCF, on LV-strain multivariate, EF was no longer significant, but LV-strain less negative than -13 (RR 2.0, P=0.008) and Mayo (2012) stage ≥ 3 (RR 2.0, P=0.008) predicted independently OS. Conclusions: MCF ≤21% identified a subgroup of patients with a high mortality risk, and it was independent of the Mayo (2012) staging but highly correlated with LV strain. An advantage of MCF, which is a novel volumetric measurement of the left ventricular chamber, is that, unlike LV-strain, MCF is simple to calculate from routine ECHO measures. Figure 1. Overall survival of 722 patients according to MCF<21%. Figure 1. Overall survival of 722 patients according to MCF<21%. Disclosures Kumar: AbbVie: Research Funding; Celgene: Research Funding; Janssen: Research Funding; Skyline, Noxxon: Honoraria; Celgene, Millenium, Sanofi, Skyline, BMS, Onyx, Noxxon,: Other: Consultant, no compensation,; Sanofi: Research Funding; Millenium/Takeda: Research Funding; Onyx: Research Funding.

Cardiomyopathy is a manifestation of transthyretin amyloidosis (ATTR), which is an underrecognized systemic disease whereby the transthyretin protein misfolds to form fibrils that deposit in various tissues and organs. ATTR amyloidosis is debilitating and associated with poor life expectancy, especially in those with cardiac dysfunction, but a variety of treatment options have recently become available. Considered a rare disease, ATTR amyloidosis may be more prevalent than thought, particularly in older persons. Diagnosis is often delayed because of a lack of disease awareness and the heterogeneity of symptoms at presentation. Given the recent availability of effective treatments, early recognition and diagnosis are especially critical because treatment is likely more effective earlier in the disease course. The Amyloidosis Research Consortium recently convened a group of experts in ATTR amyloidosis who, through an iterative process, agreed on best practices for suspicion, diagnosis, and characterization of disease. This review describes these consensus recommendations for ATTR associated with cardiomyopathy as a resource to aid cardiologists and others in the recognition and diagnosis of ATTR associated with cardiomyopathy. Included in this review is an overview of red flag signs and symptoms and a recommended diagnostic approach, including testing for monoclonal protein, scintigraphy, or biopsy and, if ATTR associated with cardiomyopathy is identified, TTR genotyping.

Background: Hereditary transthyretin-mediated (hATTR) amyloidosis is a rapidly progressive, multisystem disease that presents with cardiomyopathy or polyneuropathy. The APOLLO study assessed the efficacy and tolerability of patisiran in patients with hATTR amyloidosis. The effects of patisiran on cardiac structure and function in a prespecified subpopulation of patients with evidence of cardiac amyloid involvement at baseline were assessed. Methods: APOLLO was an international, randomized, double-blind, placebo-controlled phase 3 trial in patients with hATTR amyloidosis. Patients were randomized 2:1 to receive 0.3 mg/kg patisiran or placebo via intravenous infusion once every 3 weeks for 18 months. The prespecified cardiac subpopulation comprised patients with a baseline left ventricular wall thickness ≥13 mm and no history of hypertension or aortic valve disease. Prespecified exploratory cardiac end points included mean left ventricular wall thickness, global longitudinal strain, and N -terminal prohormone of brain natriuretic peptide. Cardiac parameters in the overall APOLLO patient population were also evaluated. A composite end point of cardiac hospitalizations and all-cause mortality was assessed in a post hoc analysis. Results: In the cardiac subpopulation (n=126; 56% of total population), patisiran reduced mean left ventricular wall thickness (least-squares mean difference ± SEM: –0.9±0.4 mm, P =0.017), interventricular septal wall thickness, posterior wall thickness, and relative wall thickness at month 18 compared with placebo. Patisiran also led to increased end-diastolic volume (8.3±3.9 mL, P =0.036), decreased global longitudinal strain (–1.4±0.6%, P =0.015), and increased cardiac output (0.38±0.19 L/min, P =0.044) compared with placebo at month 18. Patisiran lowered N -terminal prohormone of brain natriuretic peptide at 9 and 18 months (at 18 months, ratio of fold-change patisiran/placebo 0.45, P <0.001). A consistent effect on N -terminal prohormone of brain natriuretic peptide at 18 months was observed in the overall APOLLO patient population (n=225). Median follow-up duration was 18.7 months. The exposure-adjusted rates of cardiac hospitalizations and all-cause death were 18.7 and 10.1 per 100 patient-years in the placebo and patisiran groups, respectively (Andersen–Gill hazard ratio, 0.54; 95% CI, 0.28–1.01). Conclusions: Patisiran decreased mean left ventricular wall thickness, global longitudinal strain, N -terminal prohormone of brain natriuretic peptide, and adverse cardiac outcomes compared with placebo at month 18, suggesting that patisiran may halt or reverse the progression of the cardiac manifestations of hATTR amyloidosis. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01960348.

Background Sex‐related differences in morbidity and survival in bicuspid aortic valve (BAV) adults are fundamentally unknown. Contemporary studies portend excellent survival for BAV patients identified at early echocardiographic‐clinical stages. Whether BAV adults incur a survival disadvantage throughout subsequent echocardiographic‐clinical stages remains undetermined. Methods and Results Analysis was done of 3 different cohorts of consecutive patients with echocardiographic diagnosis of BAV identified retrospectively: (1) a community cohort of 416 patients with first BAV diagnosis (age 35±21 years, follow‐up 16±7 years), (2) a tertiary clinical referral cohort of 2824 BAV adults (age 51±16 years, follow‐up 9±6 years), and (3) a surgical referral cohort of 2242 BAV adults referred for aortic valve replacement (AVR) (age 62±14 years, follow‐up 6±5 years). For the community cohort, 20‐year risks of aortic regurgitation (AR), AVR, and infective endocarditis were higher in men (all P ≤0.04); for a total BAV‐related morbidity risk of 52±4% vs 35±6% in women ( P =0.01). The cohort's 25‐year survival was identical to that in the general population ( P =0.98). AR independently predicted mortality in women ( P =0.001). Baseline AR was more common in men ( P ≤0.02) in the tertiary cohort, with 20‐year survival lower than that in the general population ( P <0.0001); age‐adjusted relative death risk was 1.16 (95% confidence interval [CI] 1.05‐1.29) for men versus 1.67 (95% CI 1.38‐2.03) for women ( P =0.001). AR independently predicted mortality in women ( P =0.01). Baseline AR and infective endocarditis were higher in men (both ≤0.001) for the surgical referral cohort, with 15‐year survival lower than that in the general population ( P <0.0001); age‐adjusted relative death risk was 1.34 (95% CI 1.22‐1.47) for men versus 1.63 (95% CI 1.40‐1.89) for women ( P =0.026). AR and NYHA class independently predicted mortality in women (both P ≤0.04). Conclusions Within evolving echocardiographic‐clinical stages, the long‐term survival of adults with BAV is not benign, as both men and women incur excess mortality. Although BAV‐related morbidity is higher in men in the community, and AR and infective endocarditis are more prevalent in men, women exhibit a significantly higher relative risk of death in tertiary and surgical referral cohorts, which is independently associated with AR.