Prevalence and clinical outcomes of transthyretin amyloidosis: a systematic review and meta-analysis.

AIM: Systematic evidence on the prevalence and clinical outcome of transthyretin amyloidosis (ATTR) is missing. We explored: (i) the prevalence of cardiac amyloidosis in various patient subgroups, (ii) survival estimates for ATTR subtypes, and (iii) the effects of novel therapeutics on the natural course of disease. METHODS AND RESULTS: A systematic review of literature published in MEDLINE before 31 December 2021 was performed for the prevalence of cardiac amyloidosis and all-cause mortality of ATTR patients. Extracted data included sample size, age, sex, and all-cause mortality at 1, 2, and 5 years. Subgroup analyses were performed for ATTR subtype, that is, wild-type ATTR (wtATTR) versus hereditary ATTR (hATTR), hATTR genotypes, and treatment subgroups. We identified a total of 62 studies (n = 277 882 individuals) reporting the prevalence of cardiac amyloidosis, which was high among patients with a hypertrophic cardiomyopathy phenotype, heart failure with preserved ejection fraction, and the elderly with aortic stenosis. Data on ATTR mortality were extracted from 95 studies (n = 18 238 ATTR patients). Patients with wtATTR were older (p = 7 × 10-10 ) and more frequently male (p = 5 × 10-20 ) versus hATTR. The 2-year survival of ATTR was 73.3% (95% confidence interval [CI] 70.9-75.7); for non-subtyped ATTR 70.4% (95% CI 66.9-73.9), for wtATTR 76.0% (95% CI 73.0-78.9]) and for hATTR 77.2% (95% CI 74.0-80.4); in meta-regression analysis, wtATTR was associated with higher survival after adjusting for confounders. There was an interaction between survival and hATTR genotypes (p = 10-15 , Val30Met having the lowest and Val122Ile/Thr60Ala the highest mortality). ATTR 2-year survival was higher on tafamidis/patisiran compared to natural disease course (79.9%, 95% CI 74.4-85.3 vs. 72.4%, 95% CI 69.8-74.9, p < 0.05). CONCLUSIONS: We report the prevalence of ATTR in various population subgroups and provide survival estimates for the natural course of disease and the effects of novel therapeutics. Important gaps in worldwide epidemiology research in ATTR were identified.

Biomarkers of Atrial Fibrillation in Metabolic Syndrome.

Whether the increased atrial fibrillation (AF) risk in metabolic syndrome (MetS) patients is due to the syndrome as a whole or simply the sum of the risks of its individual component parts is still obscure. These two clinical entities share many pathophysiological links and thus distinction between a casual observation and a significant association is difficult. Biomarkers associated with pathogenesis of AF in the context of MetS have the ability to refine future risk prediction. In the present review we identify circulating substances that could be regarded as potential biomarkers for prediction of incident AF, or of cardiovascular events in the setting of AF in patients with MetS. Cardiac myocyte injury and stress markers (troponin and natriuretic peptides), markers of renal function (glomeral filtration rate, cystatin-C), and inflammation markers/mediators (interleukin- 6, CRP) are promising biomarkers of patients with AF and MetS.

Amino-terminal pro-C-type natriuretic peptide is associated with arterial stiffness, endothelial function and early atherosclerosis.

OBJECTIVE: C-type natriuretic peptide (CNP) is a paracrine molecule with effects on endothelial integrity, vascular tone and atherosclerotic process. Arterial stiffness, wave reflections, endothelial dysfunction and carotid intima-media thickness (IMT) are predictors of cardiovascular events. We investigated whether CNP is related to arterial structure and function in men. METHODS: We evaluated arterial structural and functional characteristics in 117 consecutive men (mean age 57.3 + or - 9.2 years), with and without cardiovascular risk factors, who had no established cardiovascular disease. Arterial elastic properties were evaluated with carotid-femoral pulse wave velocity (PWV), wave reflections with augmentation index (AIx), endothelial function with flow-mediated dilatation of the brachial artery (FMD) and early atherosclerosis with carotid IMT. Amino-terminal proCNP (NT-proCNP) was assessed in venous blood. RESULTS: The number of cardiovascular risk factors was inversely related to levels of NT-proCNP (P<0.01) and there was a progressive increase in Framingham risk score according to decreasing tertiles of NT-proCNP (P<0.001). In multivariable regression analysis NT-proCNP exhibited significant negative associations with PWV and IMT and positive association with FMD (all P<0.05) that were independent of age, blood pressure, smoking habits, body mass index, blood glucose, total triglycerides, low-density lipoprotein and endothelin-1 or high-sensitivity C-reactive protein. There was no relation between NT-proCNP and AIx. CONCLUSION: The present study is the first to demonstrate in a global arterial approach relationship between CNP and functional and early structural arterial changes. These findings elucidate pathophysiological links and may have important clinical implications for the estimation of cardiovascular risk in men.