Rare c.302C>T TTR Variant Associated with Transthyretin Amyloidosis

Background and Objectives: Hereditary transthyretin amyloidosis (ATTRv) is a rare disease caused by pathogenic variants in the transthyretin (TTR) gene. More than 140 different disease-causing variants in TTR have been reported. Only a few individuals with a rare TTR variant, c.302C>T, p.(Ala101Val) (historically known as p.(Ala81Val)), primarily associated with cardiac ATTRv, have been described. Therefore, our aim was to analyze the clinical characteristics of individuals with the identified c.302C>T TTR variant at our center. Materials and Methods: We analyzed data from individuals with ATTRv who were diagnosed and treated at Vilnius University Hospital Santaros Klinikos. ATTRv was confirmed by negative hematological analysis for monoclonal protein, positive tissue biopsy or bone scintigraphy and a pathogenic TTR variant. Results: During 2018-2021, the TTR NM_000371.3:c.302C>T, NP_000362.1:p.(Ala101Val) variant was found in one individual in a homozygous state and in three individuals in a heterozygous state. The age of onset of symptoms ranged from 44 to 74 years. The earliest onset of symptoms was in the individual with the homozygous variant. A history of carpal tunnel syndrome was identified in two individuals. On ECG, three individuals had low QRS voltage in limb leads. All individuals had elevated NT-proBNP and hsTroponine I levels on baseline laboratory tests and concentric left ventricular hypertrophy on transthoracic echocardiography. The individual with the homozygous c.302C>T TTR variant had the most pronounced polyneuropathy with tetraparesis. Other patients with the heterozygous variant had more significant amyloid cardiomyopathy. When screening family members, the c.302C>T TTR variant was identified in two phenotypically negative relatives at the ages of 33 and 47 years. Conclusions: c.302C>T is a rare TTR variant associated with ATTRv cardiomyopathy. The homozygous state of this variant was not reported before, and is associated with earlier disease onset and neurological involvement compared to the heterozygote state.

Electrocardiographic Markers of Adverse Left Ventricular Remodeling and Myocardial Fibrosis in Severe Aortic Stenosis

The optimal timing for aortic valve replacement (AVR) in aortic stenosis (AS) is still controversial and may be guided by markers of adverse left ventricular (LV) remodeling. We aim to assess electrocardiographic (ECG) strain in relation to LV remodeling and myocardial fibrosis. 83 severe AS patients underwent surgical AVR, with preoperative 12-lead ECG, cardiovascular magnetic resonance with T1 mapping and echocardiography with global longitudinal strain analysis. Collagen volume fraction (CVF) was measured in myocardial biopsies sampled during AVR. Patients with ECG strain had more severe AS, more advanced LV remodeling and evidence of heart failure. Patients with ECG strain had more diffuse fibrosis, as evident by higher mean native T1 values (974.8 ± 34 ms vs. 946.5 ± 28 ms, p < 0.001). ECG strain was the only predictor of increased LV mass index on multivariate regression analysis (OR = 7.10, 95% CI 1.46-34.48, p = 0.02). Patients with persistent ECG strain at 1 year following AVR had more advanced LV remodeling and more histological fibrosis (CVF 12.5% vs. 7.3%, p = 0.009) at baseline assessment. Therefore, ECG strain is a marker of adverse LV remodeling and interstitial myocardial fibrosis. Lack of improvement in ECG strain following AVR indicates more advanced baseline LV injury and higher levels of myocardial fibrosis.

Type 2 Myocardial Infarction and Long-Term Mortality Risk Factors: A Retrospective Cohort Study

INTRODUCTION

In-hospital risk factors for type 1 myocardial infarction (MI) have been extensively investigated, but risk factors for type 2 MI are still emerging. Moreover, type 2 MI remains an underdiagnosed and under-researched condition. Our aim was to assess survival rates after type 2 MI and to analyze the risk factors for patient prognosis after hospitalization.

METHODS

We conducted a retrospective database analysis of patients with MI diagnosis who were treated in Vilnius University Hospital Santaros Klinikos. A total of 6495 patients with the diagnosis of MI were screened. The primary study endpoint was long-term all-cause mortality. The predictive value of laboratory tests was estimated including blood hemoglobin, D dimer, creatinine, brain natriuretic peptide (BNP), C-reactive protein (CRP), and troponin levels.

RESULTS

Out of all the patients diagnosed with MI there were 129 cases of type 2 MI (1.98%). Death rate almost doubled from 19.4% at 6 months to 36.4% after 2 years of follow-up. Higher age and impaired kidney function were risk factors for death both during hospitalization and after 2 years of follow-up. Lower hemoglobin (116.6 vs. 98.9 g/L), higher creatinine (90 vs. 161.9 μmol/L), higher CRP (31.4 vs. 63.3 mg/l), BNP (707.9 vs. 2999.3 ng/L), and lower left ventricle ejection fraction were all predictors of worse survival after 2 years of follow-up. Preventive medication during hospitalization can decrease the mortality risk: angiotensin-converting enzyme inhibitor (ACEi) (HR 0.485, 95% CI 0.286-0.820) and statins (HR 0.549, 95% CI 0.335-0.900). No significant influence was found for beta blockers (HR 0.662, 95% CI 0.371-1.181) or aspirin (HR 0.901, 95% CI 0.527-1.539).

CONCLUSIONS

There is significant underdiagnosis of type 2 MI (1.98% out of all MIs). If the patient is prescribed a preventive medication like ACEi or statins, the mortality risk is lower. Increased awareness of elevation of laboratory results could help to improve the treatment of these patients and identify the most vulnerable groups.

Exploring myocardial fibrosis in severe aortic stenosis: echo, CMR and histology data from FIB-AS study

Myocardial fibrosis in aortic stenosis is associated with worse survival following aortic valve replacement. We assessed myocardial fibrosis in severe AS patients, integrating echocardiographic, cardiovascular magnetic resonance (CMR) and histological data. A total of 83 severe AS patients (age 66.4 ± 8.3, 42% male) who were scheduled for surgical AVR underwent CMR with late gadolinium enhancement and T1 mapping and global longitudinal strain analysis. Collagen volume fraction was measured in myocardial biopsies (71) that were sampled at the time of AVR. Results. CVF correlated with imaging and serum biomarkers of LV systolic dysfunction and left side chamber enlargement and was higher in the sub-endocardium compared with midmyocardium (p<0.001). CVF median values were higher in LGE-positive versus LGE-negative patients [28.7% (19-33) vs 20.7% (15-30), respectively, p=0.040]. GLS was associated with invasively (CVF; r=-0.303, p=0.013) and non-invasively (native T1; r=-0.321, p<0.05) measured myocardial fibrosis. GLS and native T1 correlated with parameters of adverse LV remodelling, systolic and diastolic dysfunction and serum biomarkers of heart failure and myocardial injury. Conclusion. Our data highlight the role of myocardial fibrosis in adverse cardiac remodelling in AS. GLS has potential as a surrogate marker of myocardial fibrosis, and high native T1 and low GLS values differentiated patients with more advanced cardiac remodelling.

Two Novel Variants in Genes of Arrhythmogenic Right Ventricular Cardiomyopathy - a Case Report

Summary. Background.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable cardiomyopathy, characterized by fibrofatty replacement of myocytes in the right ventricular, left ventricular or both ventricles. It is caused by pathogenic variants of genes encoding desmosomal (JUP, DSP, PKP2, DSG2, DSC2) and non-desmosomal proteins, and is one of the most common causes of sudden cardiac death in young athletes. Therefore, early identification, correct prevention and treatment can prevent adverse outcomes.

Case report.

Our case presents a 65-years-old man with recurrent ventricular tachycardia. The ischemic cause was the first to rule out. Echocardiography revealed right ventricular structural and functional abnormalities. After suspicion of ARVC, magnetic resonance imaging was performed showing reduced right ventricular ejection fraction with local aneurysms, structural changes ir the right and left myocardium. Subsequently performed genetic testing identified a novel ARVC likely pathogenic variant in DSC2 gene and variant of uncertain significance in RYR2 gene.

Conclusions.

Diagnostic evaluation of ARVC is challenging and requires multidisciplinary team collaboration. Further functional tests for elucidation of the clinical significance of the two novel variants of ARVC-associated genes could be suggested.

Prognostic value of myocardial fibrosis in severe aortic stenosis: study protocol for a prospective observational multi-center study (FIB-AS)

Background

Adverse cardiac remodeling with a myocardial fibrosis as a key pathophysiologic component may be associated to worse survival in aortic stenosis (AS) patients. Therefore, with the application of advanced cardiac imaging we aim to investigate left ventricular myocardial fibrosis in severe AS patients undergoing aortic valve replacement (AVR) and determine its impact with post-intervention clinical outcomes.

Methods

In a prospective, observational, cohort study patients with severe AS scheduled either for surgical or transcatheter AVR will be recruited from two tertiary heart centers in Denmark and Lithuania. All patients will receive standard of care in accordance with the current guidelines and will undergo additional imaging testing before and after AVR: echocardiography with deformation analysis and cardiovascular magnetic resonance (CMR) with T1 parametric mapping. Those undergoing surgical AVR will also have a myocardial biopsy sampled at the time of a surgery for histological validation. Patients will be recruited over a 2-year period and followed up to 2 years to ascertain clinical outcomes. Follow-up CMR will be performed 12 months following AVR, and echocardiography with deformation analysis will be performed 3, 12, and 24 months following AVR. The study primary outcome is a composite of all-cause mortality and major adverse cardiovascular events.

Discussion

Despite continuous effort of research community there is still a lack of early predictors of left ventricular decompensation in AS, which could improve patient risk stratification and guide the optimal timing for aortic valve intervention, before irreversible left ventricular damage occurs. Advanced cardiac imaging and CMR derived markers of diffuse myocardial fibrosis could be utilized for this purpose. FIB-AS study is intended to invasively and non-invasively assess diffuse myocardial fibrosis in AS patients and investigate its prognostic significance in post-interventional outcomes. The results of the study will expand the current knowledge of cardiac remodeling in AS and will bring additional data on myocardial fibrosis and its clinical implications following AVR.

Ethics/dissemination

The study has full ethical approval and is actively recruiting patients. The results will be disseminated through scientific journals and conference presentations.

Trial registration

ClinicalTrials.govNCT03585933. Registered on 02 July 2018.

Clinical features and three-year outcomes of Takotsubo (stress) cardiomyopathy: Observational data from one center

OBJECTIVE

The natural history, management, and outcome of Takotsubo (stress) cardiomyopathy (TTC) is not clear. The aim of this study was to investigate clinical features, define prognostic predictors, and assess the clinical course and outcomes of patients with TTC.

METHODS

We analyzed 64 patients (52 women) meeting the proposed Mayo Clinic diagnostic criteria for TTC. All patients were treated at Vilnius University Hospital Santariskiu Klinikos from 2001-01-01 to 2014-11-27. Data were collected on the basis of medical records and follow-up data was collected by phone.

RESULTS

The mean age of analyzed patients was 63.4 ± 14.6 years; the mean follow-up was 2.9 years. More than half of the patients (52%) did not have any clear stressful triggers. During admission, symptoms such as chest pain (64%) and general weakness (45%) were reported more often than other symptoms. Almost all patients (94%) had the classical TTC form; the remaining 6% of patients had "inverted" TTC. The mean left ventricular ejection fraction (LVEF) on admission was 37.7% (± 8.2%). A pseudonormal or restrictive pattern of LV filling, moderate to severe mitral regurgitation (MR), and right ventricular involvement were uncommon in the patients. The in-hospital course showed cardiogenic shock in 23% of the cases, resulting in the death of 5 (8%) patients. We discovered that only peak concentration of troponin I was a significant predictor of in-hospital mortality (HR 1.067, 95%CI 1.022-1.113, p=0.003). At the end of the follow-up period, 45 (87%) women and 8 (67%) men were alive. This makes the overall observed mortality at 3 years approximately 17.2%. Using multivariate analysis, elevation of BNP (HR for increase by 10 ng/l 1.002, 95%CI 1-1.003, p=0.022) and cardiogenic shock on admission (HR 8.696, 95%CI 1.198-63.124, p=0.032) were significant predictors of overall mortality. Other prognostic factors assessed on admission were nonsignificant predictors of overall mortality.

CONCLUSIONS

Our analysis shows that in-hospital mortality is influenced by the peak concentration of troponin I, and overall mortality is affected by cardiogenic shock and the elevation of BNP during admission. The assessment of troponin I and BNP can help with the prognostication of TTC patients in our daily clinical practice.

Isolated nasal amyloidosis: a case report

Amyloidosis is a rare condition characterized by the deposition of abnormal protein filaments into the extracellular tissue. Only 16 cases of true primary idiopathic amyloidosis localized in the nose and the paranasal sinuses have previously been reported. We present a case of localized amyloidosis involving the sinonasal cavities and the nose in a 53-year-old woman. Our patient was operated on as a typical case of chronic rhinosinusitis with polyps, but after 2 years, the patient came back with severe symptoms of nasal obstruction and pain in the frontal and maxillary regions with proptosis of both eyes. Magnetic resonance imaging revealed sinonasal-intraorbital masses. Primary amyloidosis (AL type) was confirmed by tissue biopsy. A systemic workup for additional amyloid deposits revealed no evidence of other diseases. Extended surgery produced a symptomatic improvement.

Age-dependent heterogeneity of familiar hypertrophic cardiomyopathy phenotype: a role of cardiovascular magnetic resonance

In this case report, we present familiar hypertrophic cardiomyopathy with age-dependent heterogeneity of the disease phenotype among the members of one family who carry the same mutation of the myosin-binding protein C gene. Phenotypic heterogeneity is common in patients with familial forms of hypertrophic cardiomyopathy, both in clinical expression and outcome. Compared with other noninvasive cardiac imaging modalities, cardiovascular magnetic resonance provides an opportunity to more accurately characterize the varying phenotypic presentations of hypertrophic cardiomyopathy.

Differentiation of acute myocarditis and acute myocardial infarction by the regional distribution of myocardial irreversible injury using cardiovascular magnetic resonance imaging

BACKGROUND AND OBJECTIVE

In this study, we have sought for differences between cardiovascular magnetic resonance patterns of acute myocarditis and acute myocardial infarction.

MATERIAL AND METHODS

A prospective analysis of 110 consecutive patients was performed. The presence, precise location, and pattern of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance were investigated.

RESULTS

The subendocardial LGE pattern was much more frequent in the myocardial infarction group (76.7%) than myocarditis group (10.0%) (P<0.001). Meanwhile, midmyocardial LGE was much more typical of myocarditis (65.0%) than acute myocardial infarction (1.1%) (P<0.001), and epicardial LGE was also much more typical of myocarditis (55.0%) than acute myocardial infarction (0.0%) (P<0.001). Midmyocardial and epicardial LGE patterns were defined as a nonischemic LGE pattern more typical of myocarditis. Logistic regression analysis revealed that the subendocardial and midmyocardial LGE locations played the greatest role in differentiation between acute myocarditis and acute myocardial infarction. A statistical model based on midmyocardial LGE distribution and age showed a sensitivity of 90% and a specificity of 93.3% in differentiating between acute myocarditis and acute myocardial infarction.

CONCLUSION

Our findings suggest that in clinical practice, differentiation between acute myocardial infarction and acute myocarditis can be done based on the subendocardial and midmyocardial LGE location. The presence of subendocardial LGE was found to be strongly associated with acute myocardial infarction; meanwhile, the presence of midmyocardial LGE indicated acute myocarditis. However, other clinical factors should also be taken into account when making the final diagnosis.