PubMed Health⌕ Search

Biomedical subjects

Cristina Chimenti

Publications and source records attributed to Cristina Chimenti.

At least 19 recordsLinked to original sources

Delayed gadolinium-enhanced cardiac magnetic resonance in patients with chronic myocarditis presenting with heart failure or recurrent arrhythmias.

OBJECTIVES: We evaluated the effectiveness of contrast-enhanced cardiac magnetic resonance (CE-CMR) in detecting chronic myocarditis (CM). BACKGROUND: Chronic myocarditis represents a common evolution of acute myocarditis. Although CE-CMR has been revealed to be effective in identifying areas of myocardial damage in acute myocarditis, its role in the diagnosis of chronic myocardial inflammation has not yet been investigated. METHODS: Twenty-three patients with CM underwent CE-CMR and endomyocardial biopsy (EMB). Chronic myocarditis was defined by the presence of: 1) chronic (>6 months) heart failure symptoms and/or repetitive ventricular arrhythmias; 2) no history of recent flu-like symptoms or infections; and 3) histologic evidence of active myocarditis (AM) or borderline myocarditis (BM) according to Dallas criteria. Contrast-enhanced cardiac magnetic resonance included black-blood T2-weighted (BBT2w) images without and with fat saturation and delayed three-dimensional T1 turbo field-echo inversion-recovery sequences obtained 15 min after gadolinium injection. RESULTS: Histology showed AM in 14 patients and BM in 9 patients. FatSat BBT2w revealed the presence of edema in five (36%) patients with AM but not in BM patients. Areas of late enhancement (LE) were observed in 12 (84%) subjects with AM and in 4 (44%) cases with BM. A mid-wall LE pattern was the most frequent finding in both groups while a subepicardial distribution of LE was observed only in patients with AM. CONCLUSIONS: Contrast-enhanced cardiac magnetic resonance identified areas of myocardial inflammation in up to 70% of patients with biopsy-proven CM. We suggest that CE-CMR may be a useful non-invasive diagnostic tool in patients with CM, and it may indicate and even guide the execution of left ventricular EMB with relevant prognostic and therapeutic implications.

Adult↗

Fabry's disease cardiomyopathy: echocardiographic detection of endomyocardial glycosphingolipid compartmentalization.

OBJECTIVES: We sought to identify echocardiographic hallmarks of Fabry's disease cardiomyopathy (FC). BACKGROUND: The recognition of FC from other forms of left ventricular hypertrophy (LVH) by noninvasive imaging techniques is not yet available, and diagnosis, mostly in the absence of systemic manifestations, still relies on genetic and invasive studies. METHODS: Forty consecutive patients (mean age 39 +/- 15 years, 22 men and 18 women) with an established diagnosis of Fabry's disease were submitted to echocardiographic evaluation. Control population consisted of 40 consecutive patients with hypertrophic cardiomyopathy (HCM), 40 hypertensive patients with echocardiographic evidence of LVH, and 40 age- and gender-matched healthy subjects with no LVH. All HCM patients and FC with LVH and/or cardiac symptoms underwent cardiac catheterization with left ventricular endomyocardial biopsy. RESULTS: Echocardiography showed in 83% of FC patients (95% of FC patients with LVH) a binary appearance of endocardial border absent in all HCM, hypertensive, and healthy subjects. The sensitivity and specificity of this echocardiographic feature in detecting Fabry patients in study population were 94% and 100%, respectively. Comparison of echocardiographic with histologic and ultrastructural findings showed the binary appearance to reflect an endomyocardial glycosphingolipids compartmentalization, consisting of thickened glycolipid-rich endocardium, free glycosphingolipid subendocardial storage, and an inner severely affected myocardial layer with a clear subendocardial-midwall layer gradient of disease severity. CONCLUSIONS: Echocardiographic binary appearance of left ventricular endocardial border, reflecting endomyocardial glycosphingolipids compartmentalization, represents a sensitive and specific diagnostic hallmark of Fabry's disease cardiomyopathy.

Adolescent↗

Cell death, proliferation and repair in human myocarditis responding to immunosuppressive therapy.

In this study, we evaluate cell death, proliferation and repair in left ventricular endomyocardial biopsies from 20 patients with active lymphocytic myocarditis worsening or recovering from cardiac dysfunction after 6-months immunosuppression. Apoptosis and necrosis were assessed by in situ ligation of hairpin probes, proliferation by Ki67 and MCM5 labelling of myocytes, repair by electron microscopy, morphometric study of percent myofibrillar area and real-time polymerase chain reaction of alpha-and beta-Myosin Heavy Chain (MHC). Apoptosis and necrosis decreased in post- vs pretreatment biopsies by 85 and 62%, respectively in responders, while increased by 42 and 46% in nonresponders. Ki67 and MCM5-positive myocytes were higher vs controls at baseline and increased by 43 and 38% at follow-up in responders and by 75 and 63% in nonresponders. Myofibrillar area reduced in pretreatment samples, increased by 33% at follow-up in responders, correlated with percent enhancement of ejection fraction and was associated with increased alpha-MHC expression and alpha/beta-MHC ratio. In follow-up biopsies of nonresponders, myofibrillar area diminished by 36% and correlated with percent decrease of ejection fraction. Our results suggest that recovery of cardiac function in myocarditis responding to immunosuppression is associated with inhibition of cell death, activation of cell proliferation and with newly synthesized contractile material.

Adolescent↗

Myocarditis: when to suspect and how to diagnose it in athletes.

Myocarditis should be suspected in athletes with unexplained cardiac arrhythmias and dysfunction, especially if preceded by a flu-like syndrome. An early diagnosis is desirable in order to avoid the risk of fatal consequences, since physical activity can enhance the inflammatory process. Although several diagnostic tools can be useful for the diagnosis of myocarditis, endomyocardial biopsy is still the gold standard. Athletes with myocarditis should be withdrawn from all competitive sports for at least 6 months and resume training when ventricular function and cardiac dimensions return to normal and the clinically relevant arrhythmias disappear. In the presence of life-threatening arrhythmias or rapidly progressive cardiac dysfunction an antiviral or an immunosuppressive treatment should be considered depending on whether a viral agent is present or absent, respectively, in the myocardium.

Adult↗

Cardiac histological substrate in patients with clinical phenotype of Brugada syndrome.

BACKGROUND: The role of structural heart disease and sodium channel dysfunction in the induction of electrical instability in Brugada syndrome is still debated. METHODS AND RESULTS: We studied 18 consecutive patients (15 males, 3 females; mean age 42.0+/-12.4 years) with clinical phenotype of Brugada syndrome and normal cardiac structure and function on noninvasive examinations. Clinical presentation was ventricular fibrillation in 7 patients, sustained polymorphic ventricular tachycardia in 7, and syncope in 4. All patients underwent cardiac catheterization, coronary and ventricular angiography, biventricular endomyocardial biopsy, and DNA screening of the SCN5A gene. Biopsy samples were processed for histology, electron microscopy, and molecular screening for viral genomes. Microaneurysms were detected in the right ventricle in 7 patients and also in the left ventricle in 4 of them. Histology showed a prevalent or localized right ventricular myocarditis in 14 patients, with detectable viral genomes in 4; right ventricular cardiomyopathy in 1 patient; and cardiomyopathic changes in 3. Genetic studies identified 4 carriers of SCN5A gene mutations that cause in vitro abnormal function of mutant proteins. In these patients, myocyte cytoplasm degeneration was present at histology, whereas terminal dUTP nick end-labeling assay showed a significant increase of apoptotic myocytes in right and left ventricle versus normal controls (P=0.014 and P=0.013, respectively). CONCLUSIONS: Despite an apparently normal heart at noninvasive evaluation, endomyocardial biopsy detected structural alterations in all 18 patients with Brugada syndrome. Mutations in the SCN5A gene, identified in 4 of the 18 patients, may have induced concealed structural abnormalities of myocardiocytes that accounted for paroxysmal arrhythmic manifestations.

Adult↗

Laser microdissection in clinical cardiovascular research.

Laser microdissection (LMD) is an accurate and fast method to procure pure populations of cells from complex, heterogeneous tissues under direct microscopic visualization. It can be applied to a wide range of cell preparation, including paraffin-embedded material. The morphology of the captured cells is retained, and DNA, RNA, and proteins can be extracted for molecular analysis. The potential applications of LMD to human cardiovascular research are multiple, including viral/autoimmune myocarditis and arteritis, atherosclerotic lesions, and myocardial and vascular cell proliferation and death. Molecular and genetic analysis of LMD-procured cells in cardiac and vascular tissues may provide a better understanding of several cardiac diseases.

Biopsy↗

Intramyocyte detection of Epstein-Barr virus genome by laser capture microdissection in patients with inflammatory cardiomyopathy.

BACKGROUND: The causal role of Epstein-Barr virus (EBV) in inflammatory cardiomyopathy (IC) is still unclear, because this virus is present in latently infected circulating B lymphocytes in 90% of adults. Laser capture microdissection (LCM) has been applied on endomyocardial biopsy samples from patients with IC to assess the presence of EBV genome in separately dissected lymphocytes and myocytes. METHODS AND RESULTS: Among 142 patients with cardiac dilation and dysfunction and a histological and immunohistochemical diagnosis of myocarditis, 44 had a myocardial viral infection detected by polymerase chain reaction on frozen endomyocardial biopsy samples. In 9 of them, the virus detected was EBV. LCM was performed on 5-microm-thick paraffin sections of EBV-infected hearts. Lymphocytes and myocytes were microdissected and analyzed separately by polymerase chain reaction analysis on DNA extracted from the collected cells. Blood and myocardial samples from patients with positive and negative serology for EBV were used as controls. EBV genome was detected in myocytes but not in infiltrating lymphocytes of patients, nor in myocardial samples from controls. Despite full conventional antifailure therapy, a progressive cardiac dilation and dysfunction was documented in patients with EBV-related IC at a mean of 31+/-14 months of follow-up. CONCLUSIONS: Intramyocyte detection of EBV can be obtained by LCM in up to 6.3% of patients with IC. This supports a cytopathic EBV role and suggests the opportunity for an antiviral/immunomodulatory therapy.

Adult↗

Prevalence of Fabry disease in female patients with late-onset hypertrophic cardiomyopathy.

BACKGROUND: Fabry disease (FD) has been recognized as the cause of left ventricular hypertrophy in 6% of men with late-onset hypertrophic cardiomyopathy (HCM). Although FD is considered a recessive X-linked disorder, affected women are increasingly reported. The aim of our study was to determine the prevalence of FD in female patients with HCM. METHODS AND RESULTS: Thirty-four consecutive women (mean age, 50+/-13.6 years) who received an ECG and echocardiographic diagnosis of HCM were submitted to an invasive cardiac study that included a biventricular endomyocardial biopsy. Tissue samples were analyzed for histology and electron microscopy. Peripheral blood activity of alpha-galactosidase (alpha-Gal) A was assessed in all patients. None of them had a family history of FD. Histology and electron microscopy showed in 4 patients (12%; mean age, 51.5+/-3.9 years) the presence of cell vacuoles characterized by the accumulation of glycolipid material organized in concentric lamellar structures, diagnostic for FD. In the remaining patients, histology was consistent with HCM. In all the female carriers, the heart was the only organ clinically involved in the disease, showing concentric hypertrophy in 2 patients, asymmetric hypertrophy in 1, and apical hypertrophy in 1. The alpha-Gal A enzymatic activity was 44+/-14% of control values. Genetic analysis showed the presence of alpha-Gal A gene mutation in all 4 cases. CONCLUSIONS: FD may account for up to 12% of females with late-onset HCM. Those heterozygous for FD with left ventricular hypertrophy are potential candidates for enzyme enhancement/replacement therapy.

Adult↗

Histologic findings in patients with clinical and instrumental diagnosis of sporadic arrhythmogenic right ventricular dysplasia.

OBJECTIVES: We sought to analyze the histologic findings of 30 patients with a diagnosis of arrhythmogenic right ventricular dysplasia (ARVD) based on established clinical and instrumental criteria, who did not have a family history of ARVD. BACKGROUND: The diagnostic role of endomyocardial biopsy (EMB) in patients with a clinical profile of ARVD is still debated. METHODS: Thirty patients (19 male, 11 female, mean age 27 +/- 10 years) with left bundle branch block morphology ventricular tachyarrhythmias and echocardiographic, angiographic, and magnetic resonance imaging (MRI) findings diagnostic of ARVD were studied. All patients, besides diagnostic, noninvasive, and invasive cardiac studies, underwent EMB in the apex, anterior free wall, inferior wall of the right ventricle (RV) and in the septal-apical region of the left ventricle. RESULTS: Diagnostic histologic features of ARVD were found only in 9 (30%) patients and a myocarditis, according to the Dallas criteria, in the remaining 21 (70%) patients. Morphometric evaluation of RV samples showed significant differences in fatty tissue and myocyte percent area between ARVD and myocarditis (p < 0.001). Conversely, no difference was found between the two groups in arrhythmic patterns and structural and functional echocardiographic, angiographic, and MRI RV alterations. Magnetic resonance imaging showed hyperintense signals in 67% of ARVD and in 62% of myocarditis group (p = NS). During follow-up (mean, 23 +/- 14 months), all patients with myocarditis remained stable on antiarrhythmic therapy while five patients with ARVD required implantation of an implantable cardioverter defibrillator. CONCLUSIONS: A myocarditis involving the RV can mimic ARVD. An EMB appears the most reliable diagnostic technique, with significant prognostic and therapeutic implications.

Adolescent↗

Overexpression of tumor necrosis factor (TNF)alpha and TNFalpha receptor I in human viral myocarditis: clinicopathologic correlations.

Proinflammatory cytokines, including tumor necrosis factor (TNF)alpha, have been recognized as important physiopathogenetic factors in the initiation and continuation of inflammatory cardiomyopathies. Experimental and preliminary human studies have demonstrated that TNFalpha plays a crucial role in enteroviral-induced myocarditis. In this study, we investigated the expression of TNFalpha and both its receptors (TNFRI and TNFRII) in both viral and nonviral myocarditis. Myocardial expression of TNFalpha was then correlated with different clinical and pathologic findings. TNFalpha expression was investigated in endomyocardial biopsies obtained from 38 patients with myocarditis and from eight control subjects by using reverse transcriptase-polymerase chain reaction (PCR) and immunohistochemistry. Viral etiology was diagnosed by PCR in 20 cases: enterovirus in seven, Epstein-Barr virus in four, hepatitis C virus in three, adenovirus in two, influenza virus in two, cytomegalovirus in one, and double infection adenovirus and enterovirus in one. Immunohistochemistry was also used to analyze both TNFalpha receptors (RI and RII). A semiquantitative analysis was employed (score 0-3) for necrosis, inflammation, fibrosis and immunohistochemical findings. TNFalpha mRNA and TNFalpha protein were significantly more present in viral myocarditis than in nonviral myocarditis (16/20 vs 3/18, P=0.001). Remarkable immunostaining was observed for both receptors, particularly TNFRI. Histological analysis revealed that myocardial necrosis (mean score 1.89 vs 1.15, P=0.01) and cellular infiltration (mean score 2.26 vs 1.78, P=0.05) were more prominent in TNFalpha-positive cases. Among TNFalpha-positive cases, the greater TNFalpha mRNAs, the more impaired was cardiac function. Our findings suggest that the expression of TNFalpha may play an important role in the pathogenesis of viral myocarditis of any etiology and may influence the severity of cardiac dysfunction. Cytokine effects are more strictly linked to overexpression of TNFRI.

Adolescent↗

Tissue Doppler imaging in Fabry disease.

PURPOSE OF REVIEW: The development of effective enzyme replacement/enhancement therapy makes of clinical relevance considering Fabry disease in the differential diagnosis of patients with hypertrophic cardiomyopathy. In particular the opportunity to significantly modify the clinical progression of the disease has reinforced the need for early diagnosis of Fabry cardiomyopathy. RECENT FINDINGS: The study with tissue Doppler of Fabry patients with endomyocardial biopsy-proven cardiac involvement showed a reduction of both diastolic and systolic myocardial velocities recorded at septal and lateral corners of mitral annulus. Tissue Doppler abnormalities were present not only in patients with left ventricular hypertrophy but also in younger patients with normal cardiac wall thickness and represent the first sign of myocardial damage. Furthermore tissue Doppler studies have been shown useful in detecting cardiac involvement in female carriers with no systemic manifestations of Fabry disease. In patients already submitted to enzyme-replacement therapy tissue Doppler and strain rate imaging represent useful noninvasive tools in assessing treatment efficacy. SUMMARY: Tissue Doppler imaging can provide early detection of cardiac involvement in Fabry disease and represents the most accurate and sensitive noninvasive tool for the diagnosis of myocardial dysfunction and for the assessment of cardiac improvement during enzyme replacement therapy. The detection of tissue Doppler abnormalities in female carriers may represent a hint for an invasive assessment of cardiac involvement.

Cardiomyopathies↗

Coronary and valve angiodysplasia unmasked by eosinophilic vasculitis and endomyocarditis.

A previously unreported case of a complex congenital cardiac anomaly consisting of coronary and valvular angiodysplasia, complicated by an eosinophilic endomyocardial disease, is described. The disorder presented clinically with congestive heart failure, which was characterized by evidence of floating masses causing severe pulmonary stenosis and dysfunction of the mitral and aortic valves. Symptoms of cardiac failure disappeared following pulmonary valve replacement and steroid therapy.

Angiodysplasia↗

Clozapine-induced hypersensitivity myocarditis.

A rare, but frequently fatal, side effect of the antipsychotic drug clozapine is myocarditis. We report a case of hypersensitivity myocarditis secondary to clozapine administration that was diagnosed in vivo for the first time through endomyocardial biopsy and was successfully treated with corticosteroids. Histologic diagnosis was based on the evidence of eosinophilic infiltration of the endomyocardium and eosinophil degranulation. Endomyocardial biopsy was performed in order to establish or exclude a clear-cut relationship between cardiac dysfunction and clozapine, and was crucial to establish a correct diagnosis and appropriate treatment. Clozapine withdrawal and targeted 8-day, low-dose corticosteroid therapy resolved the symptoms and restored cardiac function.

Clozapine↗

Hypertrophic cardiomyopathy: two homozygous cases with "typical" hypertrophic cardiomyopathy and three new mutations in cases with progression to dilated cardiomyopathy.

About 10% of cases of hypertrophic cardiomyopathy (HCM) evolve into dilated cardiomyopathy (DCM) with unknown causes. We studied 11 unrelated patients (pts) with HCM who progressed to DCM (group A) and 11 who showed "typical" HCM (group B). Mutational analysis of the beta-myosin heavy chain (MYH7), myosin-binding protein C (MYBPC3), and cardiac troponin T (TNNT2) genes demonstrated eight mutations affecting MYH7 or MYBPC3 gene, five of which were new mutations. In group A-pts, the first new mutation occurred in the myosin head-rod junction and the second occurred in the light chain-binding site. The third new mutation leads to a MYBPC3 lacking titin and myosin binding sites. In group B, two pts with severe HCM carried two homozygous MYBPC3 mutations and one with moderate hypertrophy was a compound heterozygous for MYBPC3 gene. We identified five unreported mutations, potentially "malignant" defects as for the associated phenotypes, but no specific mutations of HCM/DCM.

Adult↗

Senescence and death of primitive cells and myocytes lead to premature cardiac aging and heart failure.

Chronological myocardial aging is viewed as the inevitable effect of time on the functional reserve of the heart. Cardiac failure in elderly patients is commonly interpreted as an idiopathic or secondary myopathy superimposed on the old heart independently from the aging process. Thus, aged diseased hearts were studied to determine whether cell regeneration was disproportionate to the accumulation of old dying cells, leading to cardiac decompensation. Endomyocardial biopsies from 19 old patients with a dilated myopathy were compared with specimens from 7 individuals of similar age and normal ventricular function. Ten patients with idiopathic dilated cardiomyopathy were also analyzed to detect differences with aged diseased hearts. Senescent cells were identified by the expression of the cell cycle inhibitor p16INK4a and cell death by hairpin 1 and 2. Replication of primitive cells and myocytes was assessed by MCM5 labeling, myocyte mitotic index, and telomerase function. Aged diseased hearts had moderate hypertrophy and dilation, accumulation of p16INK4a positive primitive cells and myocytes, and no structural damage. Cell death markedly increased and occurred only in cells expressing p16INK4a that had significant telomeric shortening. Cell multiplication, mitotic index and telomerase increased but did not compensate for cell death or prevented telomeric shortening. Idiopathic dilated cardiomyopathy had severe hypertrophy and dilation, tissue injury, and minimal level of p16INK4a labeling. In conclusion, telomere erosion, cellular senescence, and death characterize aged diseased hearts and the development of cardiac failure in humans.

Aged↗