Multi-parametric non-contrast cardiac magnetic resonance for the differentiation between cardiac amyloidosis and hypertrophic cardiomyopathy

AIM

To evaluate the ability of fast strain-encoded (SENC) cardiac magnetic resonance (CMR) derived myocardial strain and native T1 mapping to discriminate between hypertrophic cardiomyopathy (HCM) and cardiac amyloidosis.

METHODS

Ninety nine patients (57 with hypertrophic cardiomyopathy and 42 with cardiac amyloidosis) were systematically analysed. LV-ejection fraction, LV-mass index, septal wall thickness and native T1 mapping values were assessed. In addition, global circumferential and longitudinal strain and segmental circumferential and longitudinal strain in basal, mid-ventricular, and apical segments were calculated. A ratio was built by dividing native T1 values by basal segmental strain (T1-to-basal segmental strain ratio).

RESULTS

Myocardial strain was equally distributed in apical and basal segments in HCM patients, whereas an apical sparing with less impaired apical strain was noticed in cardiac amyloidosis (apical-to-basal-ratio of 1.01 ± 0.23 versus 1.20 ± 0.28, p < 0.001). T1 values were significantly higher in amyloidosis compared to HCM patients (1170.7 ± 66.4 ms versus 1078.3 ± 57.4ms, p < 0.001). The T1-to-basal segmental strain ratio exhibited high accuracy for the differentiation between the two clinical entities (Sensitivity = 85%, Specificity = 77%, AUC = 0.90, 95% CI = 0.81-0.95, p < 0.001). Multivariable analysis showed that age and the T1-to-basal-strain-ratio were the most robust factors for the differentiation between HCM and cardiac amyloidosis.

CONCLUSION

The T1-to-basal-segmental strain ratio, combining information from segmental circumferential and longitudinal strain and native T1 mapping aids the differentiation between HCM and cardiac amyloidosis with high accuracy and within a fast CMR protocol, obviating the need for contrast agent administration.

Role of cardiac CT in the diagnostic evaluation and risk stratification of patients with myocardial infarction and non-obstructive coronary arteries (MINOCA): rationale and design of the MINOCA-GR study

INTRODUCTION

Myocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%-15% of all patients with acute myocardial infarction. Cardiac MR (CMR) and optical coherence tomography have been used to identify the underlying pathophysiological mechanism in MINOCA. The role of cardiac CT angiography (CCTA) in patients with MINOCA, however, has not been well studied so far. CCTA can be used to assess atherosclerotic plaque volume, vulnerable plaque characteristics as well as pericoronary fat tissue attenuation, which has not been yet studied in MINOCA.

METHODS AND ANALYSIS

MINOCA-GR is a prospective, multicentre, observational cohort study based on a national registry that will use CCTA in combination with CMR and invasive coronary angiography (ICA) to evaluate the extent and characteristics of coronary atherosclerosis and its correlation with pericoronary fat attenuation in patients with MINOCA. A total of 60 consecutive adult patients across 4 participating study sites are expected to be enrolled. Following ICA and CMR, patients will undergo CCTA during index hospitalisation. The primary endpoints are quantification of extent and severity of coronary atherosclerosis, description of high-risk plaque features and attenuation profiling of pericoronary fat tissue around all three major epicardial coronary arteries in relation to CMR. Follow-up CCTA for the evaluation of changes in pericoronary fat attenuation will also be performed. MINOCA-GR aims to be the first study to explore the role of CCTA in combination with CMR and ICA in the underlying pathophysiological mechanisms and assisting in diagnostic evaluation and prognosis of patients with MINOCA.

ETHICS AND DISSEMINATION

The study protocol has been approved by the institutional review board/independent ethics committee at each site prior to study commencement. All patients will provide written informed consent. Results will be disseminated at national meetings and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT4186676.

The Interplay between Myocardial Fibrosis, Strain Imaging and Collagen Biomarkers in Adults with Repaired Tetralogy of Fallot

Background: We sought to assess the interplay between right ventricle (RV) fibrosis, biventricular dysfunction based on global longitudinal strain (GLS) analysis, and biomarkers such as Galectin-3 (Gal-3), procollagen type III (PCIII), and NTproBNP. Methods: We studied 35 adult patients with rToF. All patients underwent a cardiac magnetic resonance (CMR) scan including feature tracking for deformation imaging. Blood biomarkers were measured. Results: LGE RV was detected in all patients, mainly at surgical sites. Patients with the highest RV LGE scoring had greater RV dilatation and dysfunction whereas left ventricular (LV) function was preserved. LV GLS correlated with RV total fibrosis score (p = 0.007). A LV GLS value of −15.9% predicted LGE RV score > 8 (AUC 0.754 (p = 0.02)). Neither RV GLS nor biomarker levels were correlated with the extent of RV fibrosis. A cut-off value for NTproBNP of 145.25 pg/mL predicted LGE RV score > 8 points (AUC 0.729, (p = 0.03)). A cut-off value for Gal-3 of 7.42 ng/mL predicted PR Fraction > 20% [AUC 0.704, (p = 0.05)]. Conclusions: A significant extent of RV fibrosis was mainly detected at surgical sites of RV, affecting RV performance. CMR-FT reveals subtle LV dysfunction in rToF patients, due to decreased performance of the fibrotic RV. Impaired LV function and elevated NTproBNP in rToF reflect a dysfunctional fibrotic RV.

Endovascular management of subclavian-steal syndrome in a patient with post-traumatic dissection of an aberrant right subclavian artery

BACKGROUND

An aberrant right subclavian artery is the most common congenital anomaly of the aortic arch and may cause symptoms due to aneurysmal dilatation, stenosis or occlusion. We present a case of subclavian-steal syndrome due to post-traumatic dissection of an aberrant right subclavian artery.

METHODS AND RESULTS

A 50 year-old man presented with dizziness and fainting episodes after exercising his right arm and a systolic blood pressure gradient of 40 mm Hg between the 2 arms. Suspecting a subclavian steal syndrome, a computed tomography angiography was requested which revealed an aberrant right subclavian artery with a severe stenosis proximal to the ostium of the vertebral artery. Transfemoral digital subtraction angiography showed a local dissection of the aberrant right subclavian artery with late retrograde filling of the ipsilateral vertebral artery. The lesion was successfully treated with primary stent implantation (9 mm x 40 mm, LIFESTAR, BARD). On interrogation, the patient recalled an injury to the right arm after falling off a ladder 10 years earlier, as a possible post-traumatic cause for the dissection. He had an uneventful outcome and is symptom-free 12 months down the line.

CONCLUSIONS

The combination of post-traumatic dissection of an aberrant right subclavian artery resulting to subclavian steal syndrome is an extremely rare scenario. Endovascular management is a safe, minimally invasive alternative to open surgery.

Parachute-like mitral valve as a cause of mitral regurgitation

BACKGROUND

Parachute mitral valve (PMV) is commonly associated with mitral valve stenosis but may occasionally be associated with mitral valve regurgitation.

CASE REPORT

We present a case of an asymptomatic 41-year-old female with a background of incomplete Shone's complex displaying a PMV regurgitation pattern.

CONCLUSION

Cardiovascular imaging with the use of transoesophageal echocardiogram and cardiac magnetic resonance were essential tools for the diagnosis and quantification of the severity of mitral valve regurgitation. Hippokratia 2016, 20(3): 238-240.

Right ventricular myxoma in a patient with tetralogy of Fallot

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Myxoma and repaired tetralogy of Fallot in the absence of a familiar trait.

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Myxoma may aggravate symptoms in patients with repaired tetralogy of Fallot.

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Combined pulmonary valve replacement and myxoma excision is feasible in this setting.

INTRODUCTION

Cardiac myxoma is the most common primary cardiac tumour in adulthood and may present in the context of Carney's complex.

PRESENTATION OF CASE

A 32-year-old male with a history of repaired tetralogy of Fallot in childhood was admitted with severe pulmonary valve regurgitation and a mobile mass in the right ventricle. The patient underwent pulmonary valve replacement and mass excision. Pathology examination showed myxoma.

DISCUSSION

In the majority of cases myxomas originate in the atria, nevertheless they can also be found in a ventricular cavity. Myxoma is a prevalent feature of Carney's complex, an inherited, autosomal disease, characterised by multiple tumours in several organs. Tetralogy of Fallot has also been described in association with Carney's complex.

CONCLUSION

Coexistence of tetralogy of Fallot with a cardiac ventricular myxoma in a patient not affected from Carney's complex or other familial syndrome.