High prevalence of heart failure with reduced ejection fraction in patients with transthyretin cardiac amyloidosis

A simple ATTR-CM score to identify transthyretin amyloid cardiomyopathy burden in HFpEF patients

BACKGROUND

Transthyretin amyloid cardiomyopathy (ATTR-CM) is often found in patients with heart failure with preserved ejection fraction (HFpEF). However, the evidence regarding ATTR-CM and prognosis in HFpEF remains scarce. This study sought to determine whether the ATTR-CM burden was associated with clinical outcomes in HFpEF patients.

METHODS

We evaluated the associations of baseline ATTR-CM score with adverse outcomes in HFpEF patients from the TOPCAT trial using the Cox proportional hazards model or the competing risk regression model. The discriminatory ability of the ATTR-CM score was assessed using the area under the time-dependent receiver operating characteristic curve (AUC).

RESULTS

We included 870 HFpEF patients, 18.9% of which had an ATTR-CM score ≥6. Per 1 increment in the ATTR-CM score was significantly associated with an increased risk of the primary outcome (adjusted hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.12-1.27) with an AUC of 0.652 (0.594-0.711), whereas patients with ATTR-CM score ≥6 presented higher risks of the primary outcome (adjusted HR 2.20, 95% CI 1.65-2.95). Similar results were observed toward the secondary outcomes.

CONCLUSIONS

The simple ATTR-CM score identified an 18.9% ATTR-CM burden in HFpEF patients, and a higher ATTR-CM burden might predict adverse outcomes with moderate discriminatory abilities in HFpEF.

Multimodality imaging for diagnosis of subclinical hereditary transthyretin cardiac amyloidosis

We present a case of a patient with worsening visual acuity and dense vitreal debris who was found to have vitreal transthyretin amyloid (ATTR) infiltration. Cardiac workup, performed to identify systemic amyloidosis, demonstrated focal myocardial amyloid infiltration on pyrophosphate (PYP) scintigraphy and cardiac magnetic resonance (CMR), resulting in a diagnosis of subclinical ATTR cardiac amyloidosis (ATTR-CA). Patient was identified as a carrier of p.S70R mutation which results in an aggressive ATTR phenotype. Patient is tolerating transthyretin silencer therapy well. Through this case, we discuss the role of a multimodality imaging approach for the diagnosis of subclinical ATTR-CA.

Estimating the Prevalence of Cardiac Amyloidosis in Old Patients with Heart Failure—Barriers and Opportunities for Improvement: The PREVAMIC Study

Background: Cardiac amyloidosis (CA) could be a common cause of heart failure (HF). The objective of the study was to estimate the prevalence of CA in patients with HF. Methods: Observational, prospective, and multicenter study involving 30 Spanish hospitals. A total of 453 patients ≥ 65 years with HF and an interventricular septum or posterior wall thickness > 12 mm were included. All patients underwent a 99mTc-DPD/PYP/HMDP scintigraphy and monoclonal bands were studied, following the current criteria for non-invasive diagnosis. In inconclusive cases, biopsies were performed. Results: The vast majority of CA were diagnosed non-invasively. The prevalence was 20.1%. Most of the CA were transthyretin (ATTR-CM, 84.6%), with a minority of cardiac light-chain amyloidosis (AL-CM, 2.2%). The remaining (13.2%) was untyped. The prevalence was significantly higher in men (60.1% vs 39.9%, p = 0.019). Of the patients with CA, 26.5% had a left ventricular ejection fraction less than 50%. Conclusions: CA was the cause of HF in one out of five patients and should be screened in the elderly with HF and myocardial thickening, regardless of sex and LVEF. Few transthyretin-gene-sequencing studies were performed in older patients. In many patients, it was not possible to determine the amyloid subtype.

Prevalence and outcomes of concomitant cardiac amyloidosis and aortic stenosis: A systematic review and meta-analysis

BACKGROUND

Cardiac amyloidosis (CA) is an increasingly recognised condition in patients with aortic stenosis (AS). However, there is large variation in the reported prevalence figures, due to differences in populations and diagnostic methods. We aimed to investigate the prevalence, risk factors and outcomes of concomitant CA and AS.

METHODS

We performed a systematic review and meta-analysis of the literature searched on Medline, EMBASE, Scopus and CENTRAL. We analysed the prevalence of CA in AS grouped according to diagnostic techniques, and the risk factors and outcomes of concomitant CA and AS was analysed in AS patients referred for surgical or transcatheter aortic valve replacement (AVR).

RESULTS

A total of 21 studies were included, involving 4,243 patients. The pooled prevalence of CA in patients with AS was 14.4%, with substantial heterogeneity. The pooled prevalence of AS in CA was 8.7%, with substantial heterogeneity. Patients with both AS and CA had higher all-cause mortality than those with AS or CA alone. In AS patients requiring AVR, CA was associated with increasing age, male sex, higher NT-proBNP levels, increased interventricular septal end diastole thickness and lower left ventricular ejection fraction. Concomitant AS and CA was associated with increased all-cause mortality and pacemaker implantation post-procedure. Study limitations included the heterogeneity of results and the fair to good quality of studies published.

CONCLUSION

Overall, a substantial proportion of patients with AS may have CA, and they have poorer prognosis. A high degree of clinical suspicion is needed to identify "red flags" and perform appropriate diagnostic imaging.

Comparison of planar with tomographic pyrophosphate scintigraphy for transthyretin cardiac amyloidosis: Perils and pitfalls

BACKGROUND

Tc-99m pyrophosphate (PYP) SPECT is recommended for indeterminate findings on planar imaging. We aimed to compare the findings on planar PYP scintigraphy alone to that of routinely performed PYP SPECT.

METHODS

PYP scintigraphy data of 133 patients (53% men; mean age 76 years) were evaluated. SPECT was routinely performed following 1-hour planar imaging, in all cases. Semiquantitative visual score and heart-to-contralateral (H/CL) ratio were determined in all patients as recommended.

RESULTS

PYP images from 35 patients (26%) were considered to be positive based on SPECT myocardial uptake. Among them, 20 (57%) had a H/CL ratio ≥1.5 and 34 had a visual score ≥ 2. SPECT identified myocardial uptake in one patient with a visual score < 2 and refuted the presence of myocardial uptake in two patients with a visual score ≥ 2. Visual score correlated well with SPECT (r = 0.94; P < .0001) and had an accuracy of 98% for tomographic myocardial uptake. Addition of H/CL ratio reduced the diagnostic performance of visual score.

CONCLUSIONS

Planar-derived visual score has an excellent accuracy for tomographic myocardial uptake, though it misclassifies a small proportion of patients. H/CL ratio decreases the diagnostic certainty of planar imaging. Tomographic imaging prevents misdiagnoses and should always be performed.