Removal of cardiac AL-amyloid with positive remodeling of cardiomyocytes and of restrictive cardiomyopathy

Herein, we describe histological mobilization of light chain cardiac amyloid documented by sequential left ventricular endomyocardial biopsies. These findings were associated with positive remodelling of cardiomyocytes and of restrictive cardiomyopathy resulting from 14 courses of chemotherapy over 17 years of time. Histological and ultrastructural findings of light chain cardiac amyloid removal led to increase in cardiomyocyte dimension and electrocardiogram voltages, reduction of biventricular wall thickness with improvement of left ventricular diastolic function, and NYHA class shifting from III to I

False-positive bone scintigraphy denoting transthyretin amyloid in elderly hypertrophic cardiomyopathy

A positive nuclear scintigraphy with hydroxy bisphosphonate bone tracer (99mTc-HPD) is believed to have high sensitivity (>99%) and specificity (91%) for the diagnosis of transthyretin amyloid cardiomyopathy. We report the case of an 85-year-old man with increased thickness of ventricular walls and a positive bone scintigraphy, who was unexpectedly found to have sarcomeric hypertrophic cardiomyopathy at left ventricular endomyocardial biopsy. Congo Red staining, immunohistochemistry, and transmission electronmicroscopy on six left ventricular samples scored negative for amyloidosis but were suggestive for sarcomeric hypertrophic cardiomyopathy. Genetic study did not show TTR and most commonly involved sarcomeric genes mutations. In hypertrophic cardiomyopathy focal cell necrosis related to demand/supply oxygen mismatch, small vessels disease or inflammation could be responsible of a false-positive bone scintigraphy signal for transthyretin amyloidosis. Because of this, especially in view of a possible specific treatment, endomyocardial biopsy is highly recommended for the correct diagnosis of cardiomyopathies with hypertrophic phenotype

Infiltration of conduction tissue is a major cause of electrical instability in cardiac amyloidosis

Abstract: Background: Pathology of conduction tissue (CT) and relative arrhythmias in living subjects with cardiac amyloid have never been reported. Aims: Reporting CT pathology and its arrhythmic correlations in human cardiac amyloidosis. Methods and Results: In 17 out of 45 cardiac amyloid patients, a left ventricular endomyocardial biopsy included conduction tissue sections. It was identified by Aschoff-Monckeberg histologic criteria and positive immunostaining for HCN4. The degree of conduction tissue infiltration was defined as mild when ≤ 30%, moderate when 30-70% and severe when > 70% cell area was replaced. Conduction tissue infiltration was correlated with ventricular arrhythmias, maximal wall thickness and type of amyloid protein. Mild involvement was observed in 5 cases, moderate in 3 and severe in 9. Involvement was associated with a parallel infiltration of conduction tissue artery. Conduction infiltration correlated with severity of arrhythmias (Spearman rho=0.8, p <0.001). In particular, major ventricular tachyarrhythmias requiring pharmacologic treatment or ICD implantation occurred in 7 patients with severe, 1 patient with moderate and none with mild conduction tissue infiltration. Pacemaker implantation was required in 3 patients with complete conduction section replacement. No significant correlation was observed between the degree of conduction infiltration and age, cardiac wall thickness or type of amyloid protein. Conclusion: Amyloid-associated cardiac arrhythmias correlate with extent of conduction tissue infiltration. Its involvement is independent from type and severity of amyloidosis, suggesting a variable affinity of amyloid protein to conduction tissue

Myocarditis-associated necrotizing coronary vasculitis: incidence, cause, and outcome

Aims : Necrotizing coronary vasculitis (NCV) is a rare entity usually associated to myocarditis which incidence, cause, and response to therapy is unreported. Methods and results : Among 1916 patients with biopsy-proven myocarditis, 30 had NCV. Endomyocardial samples were retrospectively investigated with immunohistochemistry for toll-like receptor 4 (TLR4) and real-time polymerase chain reaction (PCR) for viral genomes. Serum samples were processed for anti-heart autoantibodies (Abs), IL-1β, IL-6, IL-8, tumour necrosis factor (TNF)-α. Identification of an immunologic pathway (including virus-negativity, TLR4-, and Ab-positivity) was followed by immunosuppression. Myocarditis-NCV cohort was followed for 6 months with 2D-echo and/or cardiac magnetic resonance and compared with 60 Myocarditis patients and 30 controls. Increase in left ventricular ejection fraction ≥10% was classified as response to therapy. Control endomyocardial biopsy followed the end of treatment. Twenty-six Myocarditis-NCV patients presented with heart failure; four with electrical instability. Cause of Myocarditis-NCV included infectious agents (10%) and immune-mediated causes (chest trauma 3%; drug hypersensitivity 7%; hypereosinophilic syndrome 3%; primary autoimmune diseases 33%, idiopathic 44%). Abs were positive in immune-mediated Myocarditis-NCV and virus-negative Myocarditis; Myocarditis-NCV patients with Ab+ presented autoreactivity in vessel walls. Toll-like receptor 4 was overexpressed in immune-mediated forms and poorly detectable in viral. Interleukin-1β was significantly higher in Myocarditis-NCV than Myocarditis, the former presenting 24% in-hospital mortality compared with 1.5% of Myocarditis cohort. Immunosuppression induced improvement of cardiac function in 88% of Myocarditis-NCV and 86% of virus-negative Myocarditis patients. Conclusion : Necrotizing coronary vasculitis is histologically detectable in 1.5% of Myocarditis. Necrotizing coronary vasculitis includes viral and immune-mediated causes. Intra-hospital mortality is 24%. The immunologic pathway is associated with beneficial response to immunosuppression

Pemphigus-associated cardiomyopathy: report of autoimmune myocarditis and review of literature

Pemphigus is a rare disease characterized by bullous lesions of the skin and mucous membranes. The aetiology is autoimmune and related to the formation of IgG autoantibodies against desmogleins, which are structural proteins of desmosomes that ensure the stability of contacts between cells. Cardiac involvement in patients with pemphigus is poorly documented. We report the data in the literature on this topic and a case of pemphigus-associated autoimmune myocarditis with damage of intercalated disc responding to immunosuppressive therapy. The occurrence of cardiomyopathy with left ventricular dysfunction in patients affected by pemphigus should be appropriately screened with endomyocardial biopsy as it could be the myocardial extension of a potentially reversible autoimmune disorder

Prelamin A mediates myocardial inflammation in dilated and HIV-Associated cardiomyopathies

Cardiomyopathies are complex heart muscle diseases that can be inherited or acquired. Dilated cardiomyopathy can result from mutations in LMNA, encoding the nuclear intermediate filament proteins lamin A/C. Some LMNA mutations lead to accumulation of the lamin A precursor, prelamin A, which is disease causing in a number of tissues, yet its impact upon the heart is unknown. Here, we discovered myocardial prelamin A accumulation occurred in a case of dilated cardiomyopathy, and we show that a potentially novel mouse model of cardiac-specific prelamin A accumulation exhibited a phenotype consistent with inflammatory cardiomyopathy, which we observed to be similar to HIV-associated cardiomyopathy, an acquired disease state. Numerous HIV protease therapies are known to inhibit ZMPSTE24, the enzyme responsible for prelamin A processing, and we confirmed that accumulation of prelamin A occurred in HIV' patient cardiac biopsies. These findings (a) confirm a unifying pathological role for prelamin A common to genetic and acquired cardiomyopathies; (b) have implications for the management of HIV patients with cardiac disease, suggesting protease inhibitors should be replaced with alternative therapies (i.e., nonnucleoside reverse transcriptase inhibitors); and (c) suggest that targeting inflammation may be a useful treatment strategy for certain forms of inherited cardiomyopathy

Inflammation of Conduction Tissue in Patients with Arrhythmic Phenotype of Myocarditis

Background: Myocarditis can manifest with lone ventricular tachyarrhythmias (LVT). Elective inflammation of conduction tissue (CT) is supposed but unproved. Methods: Forty-two of 420 patients with biopsy proven myocarditis presented with LVT. Twelve of them included CT sections in endomyocardial biopsies. Real-time polymerase chain reaction (PCR) for viral genomes, immunohistochemistry for viral antigens and Toll like receptor 4 (TLR4) were performed. Twelve myocarditis patients with infarct-like or cardiomyopathic phenotype and CT included in tissue section were used as controls. Results: Four of the 12 patients presented non-sustained ventricular tachycardia (nsVT), six with sustained ventricular tachycardia (sVT), two with ventricular fibrillation. CT was inflamed in all LVT patients and not in controls (p < 0.001). PCR was positive for influenza-A virus in two, herpes simplex virus type 2 (HSV2) in one and adenovirus in one with positive CT immunostaining for viral antigens. In eight patients, negative PCR and TLR4 overexpression suggested an immune-mediated pathway. Patients with influenza-A myocarditis and CT infection responded to oseltamivir, those with HSV2 (Herpes Virus 2) and adenovirus infection died. The eight patients with immune-mediated myocarditis were treated with steroids and azathioprine. Seven of them had no more VT(ventricular tachyarrhythmias)during six-month follow-up. Conclusions: Arrhythmic phenotype of myocarditis is associated with CT inflammation/infection. Molecular characterization of CT damage may lead to pharmacologic control of arrhythmias in 75% of cases

Downregulation of Mannose-6-Phosphate Receptors in Fabry Disease Cardiomyopathy: A Potential Target for Enzyme Therapy Enhancement

Background: The efficacy of enzyme replacement therapy (ERT) in mobilizing globotryaosylceramide (GB-3) from Fabry cardiomyocytes is limited. The mechanism involved is still obscure. Methods: Assessment of M6Pr, M6Pr-mRNA, and Ubiquitin has been obtained by Western blot analysis and real-time PCR of frozen endomyocardial biopsy samples, from 17 pts with FD, various degree of left ventricular hypertrophy, and maximal wall thickening (MWT) from 11.5 and 20 mm. The diagnosis and severity of FDCM followed definitions of GLA mutation, α-galactosidase A enzyme activity, cardiac magnetic resonance, and left ventricular endomyocardial biopsy with the quantification of myocyte hypertrophy and the extent of Gb-3 accumulation. All patients have received alpha or beta agalsidase for ≥3 years without a reduction in LV mass nor an increase in T1 mapping at CMR. Controls were surgical biopsies from 15 patients undergoing mitral valve replacement. Results: Protein analysis showed mean M6Pr in FDCM to be 5.4-fold lower than in a normal heart (4289 ± 6595 vs. 23,581 ± 4074, p = 0.0996) (p p = 0.009, (p p = 0.5799, (p p = 0.001) suggesting that ubiquitin-dependent post-translational degradation is likely responsible for the reduction of M6Pr in FDCM. Conclusion: M6Pr expression is remarkably reduced in FDCM as a likely result of post-translational degradation. This may explain the reduced efficacy of ERT and be a therapeutic target for the enhancement of ERT activity

Virus-Negative Necrotizing Coronary Vasculitis with Aneurysm Formation in Human SARS-CoV-2 Infection

We report a case of myopericarditis associated to SARS-CoV-2 infection with necrotizing coronary vasculitis of intramural vessels, giving rise to biventricular apical microaneurysms and to electrical instability. Negativity of myocardial polymerase chain reaction for the most common cardiotropic viruses and for SARS-CoV-2 suggested an immune-mediated myocardial and pericardial inflammatory disease. High dose (1 mg/Kg daily) prednisone and anti-viral (Remdesivir, IDA Business, Carrigtohill, County Cork, T45 DP77, Ireland) therapy led to resolution of cardiac inflammation and ventricular arrhythmias. Morpho-molecular characterization of endomyocardial tissue may improve the outcome in subjects with SARS-CoV-2-associated myopericarditis and coronary vasculitis

Biopsy-proven autoimmune myocarditis in HIV-associated dilated cardiomyopathy

BACKGROUND: Dilated cardiomyopathy occurring in HIV-infected patients raises both diagnostic and therapeutic challenging problems. Indeed myocardial involvement in HIV infection has been variously attributed to several causes, including viral, toxic, nutritional and autoimmune, but no specific treatment capable to substantially improve patients’ prognosis has been recognized so far. CASE PRESENTATION: Hereby we describe the case of an autoimmune myocarditis manifesting with heart failure in a3 9-year-old man with HIV infection. Left ventricular endomyocardial biopsy showed a lymphocytic myocarditis characterized by over-expression of HLA-DR and negative polymerase chain reaction for cardiotropic viruses. Steroid treatment was followed by recovery of cardiac dimension and function. CONCLUSION: Presence of auto-reactive myocarditis should be considered in patients with HIV-associated dilated cardiomyopathy. Its recognition by endomyocardial biopsy followed by steroid administration may result in a complete resolution of cardiac disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12879-014-0729-3) contains supplementary material, which is available to authorized users