Incidental cardiac uptake of 99mTc-diphosphonates is predictive of poor outcome: data from 9616 bone scintigraphies

BACKGROUND

Bone scintigraphy (BS) is highly diagnostic for amyloid transthyretin (ATTR) cardiomyopathy. Prevalence and prognostic value of BS cardiac uptake is not well established. Our aim was to assess the prevalence of subclinical cardiac ATTR amyloidosis in patients undergoing [99mTc]MDP/DPD scintigraphy and to define their phenotype and prognosis.

METHODS AND RESULTS

BS scans performed for any clinical indications from 2009 to 2020 were reviewed. Patients were stratified according to Perugini visual score of cardiac uptake. Follow-up data were collected. Among 9616 BS scans, 0.7% (n = 67) showed cardiac uptake. In 47 (70%) patients, Perugini score was 1 and in 20 (30%) patients uptake was ≥ 2, suggesting cardiac ATTR amyloidosis. Forty subjects (61%) died during the follow-up (mean 47 ± 30 months). Compared with patients with Perugini score 1, those Perugini score ≥ 2 showed increased death rate (P = .018). Two (2/67) subjects were investigated for TTR gene mutations resulting negative.

CONCLUSIONS

In patients undergoing BS for different clinical indications, cardiac uptake suggesting cardiac ATTR amyloidosis is a rare, but still neglected finding, thus preventing possible diagnosis of ATTR cardiomyopathy. Importantly, cardiac uptake negatively affects the survival. Physicians should be aware of this rare, but crucial finding for timely diagnosis and treatment.

Filmin-c mutations in arrhythmogenic cardiomyopathy: a peculiar association with left dominat variant and high risk of sudden death

Introduction

Arrhythmogenic cardiomyopathy (AC) is characterized by myocyte necrosis and progressive fibro-fatty substitution. Recently, truncated mutations on Filamin C gene have been correlated with AC and a peculiar phenotype characterized by a prominent left ventricular fibrosis and high risk of sudden death.

Purpose

To evaluate clinical and instrumental features of subjects affected by AC in whom genetic study identified presence of truncating and missense mutations on FLNC gene.

Materials and methods

A population of 192 probands affected by AC according to 2010 Task Force Criteria or McKenna's proposed criteria for left dominant AC were evaluated for FLNC variants. In positive probands and families anamnestic and clinical data (ECG, echocardiographic and cardiac magnetic resonance (CMR), twenty-four-hours ECG monitoring) were evaluated.

Results

A total of 19 subjects (9 probands and 10 family members) were identified as carrier of nine different FLNC mutations (5 truncating and 4 missense). In 3 patients (23%) clinical onset was characterized by major arrhythmic episodes and in one (8%) by sudden death. In 6 (46%) ECG was unremarkable and the most common abnormalities were low QRS voltages in peripheral leads (85%), followed by T wave inversion in lateral (15%) and in inferior leads (16%). Twenty-four-hours ECG monitoring revealed a high arrhythmic burden (PVC >500/die) in 6 cases (46%). CMR was performed in all patients. Four of them (31%) showed a LV dilatation, while in 2 cases (15%) a RV dilatation was present. In 8 (61%) a fatty infiltration was detected mainly affecting the left ventricle (6 cases, 46%). Moreover, late enhancement was present in 8 cases (62%), with a LV distribution.

Conclusions

This is the first studied population in which both truncating and missense variants were evaluated as causative of AC, confirming that FLNC gene mutations are rare (4% of probands without known AC causative mutations) and the prevalent clinical expression is a left dominant phenotype with a high degree of electrical instability and recurrence of sudden familial cardiac death.

Funding Acknowledgement

Type of funding source: None

P3828Zebrafish models for arrhythmogenic cardiomyopathy type 8: a starting platform for exercise stress test and drug treatment

Background

Arrhythmogenic Cardiomyopathy (AC) is an inherited heart disease characterized by progressive substitution of the myocardium with fibro-fatty tissue, leading to electrical instability and high risk of sudden death, particularly in young subjects and athletes. In recent years, our laboratory has produced zebrafish (zf) mutant lines modelling AC type 8, an AC form linked to mutations in the junctional protein Desmoplakin (Dsp). Mutations in the DSP gene have been identified in both dominant and recessive AC cases, characterized by left-dominant and biventricular forms of the disease. Sports medicine has highlighted that they are the most dangerous forms, being less easily identifiable by ECG.

Purpose

Taking advantage of our zf Dsp mutant lines, we aim to fully characterize the pathological phenotype, analyze the perturbation of cell communication pathways, evaluate the role of the physical exercise, and test the efficacy of candidate drugs.

Methods

Among our zf lines we have identified double mutant animals, bearing both zf dspa and dspb mutations in heterozygous condition, as the best model able to recapitulate the human AC phenotype. This model underwent physical stress tests in the presence/absence of candidate drug treatment. Phenotyping included heart rhythm measurement, gene expression analysis using Real Time PCR and signaling pathway transgenes, immune-histochemistry, whole-mount in situ hybridization, standard histology and ultrastructural TEM analysis.

Results

Preliminary results from mutant phenotyping indicate alterations in heart rate, sudden cardiac death, structural alterations of the myocardium associated with junctional disorganization and, in parallel, dysregulation of Wnt, Hippo and TGFbeta pathways. Specifically, Dsp mutant animals can range from an 8% decrease to a 14% increase of heart rhythm compared to the physiological range (120–140 beats per minute in zf larvae). At the adult stage, about 1% of the fish mutant population dies suddenly. The histological examination shows a 50% reduction of the myocardial cell mass, in parallel with a 50% decrease of Dsp signal, detected by TEM, associated with the so-called “pale desmosome” phenotype. Signaling dysregulation includes an 80% loss of Wnt/Beta-catenin, a 300% increase of TGFbeta and a 500% increase of Hippo/YAP-TAZ signaling in the cardiac tissue. Physical stress tests and pathway-directed drug treatment have clarified that these factors can modulate the pathological phenotype, as preliminarily evidenced by the rescue of Wnt signal decrease to normal levels through SB216763 treatment of Dsp-deficient individuals at rest.

Conclusion

Preliminary evidences corroborate the zf organism as a suitable model for AC cellular and molecular phenotyping, exploitable for the dissection of the genetic events leading to the onset and progression of the disease, and applicable to the analysis of chemical and mechanical modulators of AC-associated features.

Acknowledgement/Funding

Cariparo 2017 SHoCD; TRANSAC; CPDA133979/13; RP-2014-ehz745.06700394

Decentration of 3-piece versus plate-haptic silicone intraocular lenses

PURPOSE

To compare the incidence of decentration with 2 types of silicone intraocular lenses (IOLs).

SETTING

John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA.

METHODS

Selection criteria for this retrospective study included patients who had uncomplicated cataract surgery with a clear cornea or scleral tunnel incision with a curvilinear capsulorhexis and capsular bag implantation of a silicone IOL. After a mean follow-up of 14 months (range 12 to 18 months), 54 eyes implanted with a 3-piece lens (AMO SI-30) and 58 eyes implanted with a plate-haptic lens (Staar AA403) were examined for posterior chamber IOL decentration. The decentration criterion was 0.5 mm or more from the center of the pupil. Detailed chart review of preoperative and postoperative measurements was performed for each patient.

RESULTS

Eighteen of the 3-piece IOLs (33%) and 11 of the plate-haptic IOLs (20%) were decentered 0.5 mm or more (P = .129). Using photographic analysis, the mean IOL decentration with the 3-piece IOL (1.12 mm +/- 0.198 [SD]) was significantly greater than with the plate-haptic IOL (0.632 +/- 0.278 mm)(P < .001). No statistically significant correlation was found between the centered or decentered IOL groups' preoperative refraction, axial length, capsulorhexis size, type of incision, or rate of neodymium:YAG laser capsulotomy.

CONCLUSIONS

No statistically significant difference was seen between the decentration rates of 3-piece and plate-hepatic IOLs; however, the amount of decentration with the 3-piece IOL was significantly greater than with the plate-hepatic IOL. Other factors did not contribute to IOL decentration.