Serenelli, Matteo

Background Transthyretin amyloid cardiomyopathy (ATTR‐CM) has a specific pathophysiology, with myocardial stiffening and systolic dysfunction only in advanced stages. We aimed to investigate the response to cardiac resynchronization therapy (CRT) in ATTR‐CM compared with heart failure. Methods In this multicenter, observational study, patients with ATTR‐CM receiving CRT (n=101) were matched to patients without amyloid cardiomyopathy by sex, age, and implantation type (CRT with versus without defibrillator versus conduction system pacing, upgrade versus first implant). We evaluated changes in QRS duration and echocardiographic parameters following CRT implantation and at the most recent available assessments. The study end points were all‐cause death alone or combined with heart failure hospitalization. Results Patients with ATTR‐CM (median age, 76 [interquartile range, 72–83] years, 98% men, left ventricular (LV) ejection fraction 30% [26–33]) showed greater QRS shortening after CRT implantation ( P =0.012), but not after a median of around 1 year ( P =0.152). There were no significant differences in the absolute LV ejection fraction changes immediately after implantation (+7 [+2/+10] versus +3 [0/+9] units; P =0.124), or to the last echo ( P =0.796), which was performed after 1.3 years in patients with ATTR‐CM and 2.9 years in patients without amyloid cardiomyopathy. Patients with ATTR‐CM had a shorter survival than controls ( P <0.001 for both end points). Patients with ATTR‐CM experiencing an early improvement in LV ejection fraction had a longer survival (log‐rank, 4.3; P =0.038). Conclusions Following CRT implantation, patients with ATTR‐CM show QRS narrowing and improvement in LV ejection fraction, not different from patients without amyloid cardiomyopathy. Early favorable LV remodeling seems to be associated with a lower risk of all‐cause death.

BACKGROUND: Thresholds to define prognosis with hs-cTnI (high-sensitivity cardiac troponin I) have not been systematically addressed in wild-type transthyretin amyloid cardiomyopathy, in part because of the multiplicity of hs-cTnI assays. The aims of this study were: first, to assess the prognostic performance of hs-cTnI measured with different assays in patients with wild-type transthyretin amyloid cardiomyopathy and, second, to identify assay-specific hs-cTnI thresholds for prognosis that could be integrated into staging systems for risk stratification. METHODS: Observational multicenter study of stable wild-type transthyretin amyloid cardiomyopathy patients from different cohorts using the Abbott Architect Stat hs-cTnI assay and the Beckman Coulter Access hs-cTnI assay (testing cohorts) and the Siemens Centaur XPT hs-cTnI assay (validation cohort). Outcome was all-cause mortality. RESULTS: In the Abbott cohort (n=136; median follow-up 22 [13–41] months; 31 [23%] deaths) and Beckman cohort (n=98; median follow-up 19 [12–28] months; 16 [16%] deaths), natural log-transformed hs-cTnI was an independent predictor of mortality (age- and sex-adjusted hazard ratio, 1.62 [95% CI, 1.11–2.35]; P =0.012 and 2.47 [95% CI, 1.48–4.14]; P <0.001, respectively). The best hs-cTnI threshold for 18-month mortality of the combined Abbott/Beckman cohorts (n=234) was 81 ng/L, rounded to 80 ng/L for simplicity of clinical use. A 2-variable staging system (based on the Mayo Clinic system) using hs-cTnI (>80 ng/L) and NPs (natriuretic peptides; NT-proBNP [N-terminal pro-B-type natriuretic peptide] >3000 ng/L or BNP [B-type natriuretic peptide] >250 ng/L) identified 3 groups with progressively worse prognosis. The staging system (using hs-cTnI >80 ng/L and NT-proBNP>3000 ng/L) was then applied to an independent cohort evaluated with the hs-cTnI Siemens assay (n=345, median follow-up 32 [24-42] months, 119 [34%] deaths). The significant differences between the groups were maintained. CONCLUSIONS: In patients with wild-type transthyretin amyloid cardiomyopathy, hs-cTnI is a strong and independent predictor of mortality. A threshold of hs-cTnI of 80 ng/L for these 3 assays provides effective risk stratification alone and in a staging system with NP.

Objective Grip strength is a well-characterised measure of weakness and of poor muscle performance, but there is a lack of consensus on its prognostic implications in terms of cardiac adverse events in patients with cardiac disorders. Methods Articles were searched in PubMed, Cochrane Library, BioMed Central and EMBASE. The main inclusion criteria were patients with cardiac disorders (ischaemic heart disease, heart failure (HF), cardiomyopathies, valvulopathies, arrhythmias); evaluation of grip strength by handheld dynamometer; and relation between grip strength and outcomes. The endpoints of the study were cardiac death, all-cause mortality, hospital admission for HF, cerebrovascular accident (CVA) and myocardial infarction (MI). Data of interest were retrieved from the articles and after contact with authors, and then pooled in an individual patient meta-analysis. Univariate and multivariate logistic regression was performed to define predictors of outcomes. Results Overall, 23 480 patients were included from 7 studies. The mean age was 62.3±6.9 years and 70% were male. The mean follow-up was 2.82±1.7 years. After multivariate analysis grip strength (difference of 5 kg, 5× kg) emerged as an independent predictor of cardiac death (OR 0.84, 95% CI 0.79 to 0.89, p<0.0001), all-cause death (OR 0.87, 95% CI 0.85 to 0.89, p<0.0001) and hospital admission for HF (OR 0.88, 95% CI 0.84 to 0.92, p<0.0001). On the contrary, we did not find any relationship between grip strength and occurrence of MI or CVA. Conclusion In patients with cardiac disorders, grip strength predicted cardiac death, all-cause death and hospital admission for HF. Trial registration number CRD42015025280.