Diagnostic approach to the patient with cardiomyopathy: whom to biopsy

Cardiac Interventional Procedures in Cardio-Oncology Patients

Comorbidities specific to the cardio-oncology population contribute to the challenges in the interventional management of patients with cancer and cardiovascular disease (CVD). Patients with cancer have generally been excluded from cardiovascular randomized clinical trials. Endovascular procedures may represent a valid option in patients with cancer with a range of CVDs because of their minimally invasive nature. Patients with cancer are less likely to be treated according to societal guidelines because of perceived high risk. This article presents the specific challenges that interventional cardiologists face when caring for patients with cancer and the modern tools to optimize care.

Myocarditis: somethings old and something new

"Since the pathological conditions take place at the cellular level, viral myocarditis and postinfectious autoimmunity can be suggested but not diagnosed clinically. All clinical methods including imaging techniques are misleading if infectious agents are involved. Accurate diagnosis demands simultaneous histologic, immunohistochemical, and molecular biological workup of the tissue. If the primary infectious or immune-mediated causes of the disease are carefully defined by clinical and biopsy-based tools, specific antiviral treatment options in addition to basic symptomatic therapy are available under certain conditions. These may allow a tailored cause-specific treatment that improves symptoms and prognosis of patients with acute and chronic disease." Uwe Kühl; Heinz-Peter SchultheissViral myocarditis.Swiss Medical Weekly. 144():w14010, JAN 2014 DOI:10.4414/smw.2014.14010.

Synthetic phosphopeptides enable quantitation of the content and function of the four phosphorylation states of phospholamban in cardiac muscle

We have studied the differential effects of phospholamban (PLB) phosphorylation states on the activity of the sarcoplasmic reticulum Ca-ATPase (SERCA). It has been shown that unphosphorylated PLB (U-PLB) inhibits SERCA and that phosphorylation of PLB at Ser-16 or Thr-17 relieves this inhibition in cardiac sarcoplasmic reticulum. However, the levels of the four phosphorylation states of PLB (U-PLB, P16-PLB, P17-PLB, and doubly phosphorylated 2P-PLB) have not been measured quantitatively in cardiac tissue, and their functional effects on SERCA have not been determined directly. We have solved both problems through the chemical synthesis of all four PLB species. We first used the synthetic PLB as standards for a quantitative immunoblot assay, to determine the concentrations of all four PLB phosphorylation states in pig cardiac tissue, with and without left ventricular hypertrophy (LVH) induced by aortic banding. In both LVH and sham hearts, all phosphorylation states were significantly populated, but LVH hearts showed a significant decrease in U-PLB, with a corresponding increase in the ratio of total phosphorylated PLB to U-PLB. To determine directly the functional effects of each PLB species, we co-reconstituted each of the synthetic peptides in phospholipid membranes with SERCA and measured calcium-dependent ATPase activity. SERCA inhibition was maximally relieved by P16-PLB (the most highly populated PLB state in cardiac tissue homogenates), followed by 2P-PLB, then P17-PLB. These results show that each PLB phosphorylation state uniquely alters Ca(2+) homeostasis, with important implications for cardiac health, disease, and therapy.

Right ventricular sarcoidosis: is it time for updated diagnostic criteria?

A 55-year-old woman with a history of complete heart block, atrial flutter, and progressive right ventricular failure was referred to our tertiary care center to be evaluated for cardiac transplantation. The patient's clinical course included worsening right ventricular dysfunction for 3 years before the current evaluation. Our clinical findings raised concerns about arrhythmogenic right ventricular cardiomyopathy. Noninvasive imaging, including a positron emission tomographic scan, did not reveal obvious myocardial pathologic conditions. Given the end-stage nature of the patient's right ventricular failure and her dependence on inotropic agents, she underwent urgent listing and subsequent heart transplantation. Pathologic examination of the explanted heart revealed isolated right ventricular sarcoidosis with replacement fibrosis. Biopsy samples of the cardiac allograft 6 months after transplantation showed no recurrence of sarcoidosis. This atypical presentation of isolated cardiac sarcoidosis posed a considerable diagnostic challenge. In addition to discussing the patient's case, we review the relevant medical literature and discuss the need for updated differential diagnostic criteria for end-stage right ventricular failure that mimics arrhythmogenic right ventricular cardiomyopathy.

Capability of three-dimensional speckle tracking radial strain for identification of patients with cardiac sarcoidosis

Since cardiac sarcoidosis (CS) leads to substantial morbidity and sudden death, early diagnosis and appropriate management are crucial for patients with CS. Echocardiography used to be considered a useful diagnostic tool for patients with CS, but CS may clinically present as dilated cardiomyopathy (DCM). Our objective was to investigate whether a novel three-dimensional (3-D) speckle-tracking strain can identify patients with CS more accurately. We studied 23 CS patients with an ejection fraction (EF) of 46 ± 10 %, and 16 EF-matched patients with DCM (EF 45 ± 11 %). Global radial (GRS), circumferential (GCS) and longitudinal (GLS) strain was assessed using 3-D speckle-tracking system. GRS of patients with CS was significantly lower than that of patients with DCM (18.5 ± 8.4 vs. 28.5 ± 8.3 %, p < 0.01), but GCS and GLS in patients with CS and DCM were similar. GRS ≦ 21.1 could differentiate CS from DCM with a sensitivity of 70 %, specificity of 88 % and area under the curve of 0.79. An additional noteworthy findings was that, patients with CS showed more negative radial strain curves than did those with DCM (1.7 ± 2.3 vs. 0.1 ± 0.5, p < 0.01). In conclusion, 3-D speckle-tracking radial strain shows good potential to distinguish CS from DCM. Our observations can thus be expected to have clinical implications for management of CS patients.

Current status of endomyocardial biopsy

Endomyocardial biopsy (EMB) is widely used for surveillance of cardiac allograft rejection and for the diagnosis of unexplained ventricular dysfunction. Typically, EMB is performed through the jugular or femoral veins and is associated with a serious acute complication rate of less than 1% using current flexible bioptomes. Although it is accepted that EMB should be used to monitor for rejection after transplant, use of EMB for the diagnosis of various myocardial diseases is controversial. Diagnosis of myocardial disease in the nontransplant recipient is often successful via noninvasive investigations including laboratory evaluation; echocardiography, nuclear studies, and magnetic resonance imaging can yield specific diagnoses in the absence of invasive EMB. Therefore, use of the technique is patient specific and depends on the potential prognostic and treatment information gained by establishing a pathologic diagnosis beyond noninvasive testing.

Myocarditis During Lenalidomide Therapy

Objective:

To report the first case of pathologically confirmed myocarditis in a patient receiving treatment with lenalidomide for non-Hodgkin's lymphoma.

Case Summary:

An 85-year-old woman with recurrent follicular lymphoma was treated with lenalidomide 10 mg daily and low-dose dexamethasone 8 mg once weekly in a clinical trial. She had a past medical history of hypertension and breast cancer. Within 17 days of starting lenalidomide and dexamethasone, she developed symptoms and signs of congestive heart failure. Despite aggressive supportive care, she had progressive and refractory multiorgan failure and died. Postmortem examination of the heart confirmed the absence of coronary artery disease, and histopathological examination of the myocardium revealed a diffuse lymphocytic/eosinophilic inflammatory infiltrate with associated acute and chronic myocardial injury affecting al 4 chambers of the heart, consistent with myocarditis.

Discussion:

Lenalidomide is an immunomodulatory agent derived from thalidomide and is approved for the treatment of multiple myeloma and myelodysplastic syndromes. The efficacy of lenalidomide has been reported in B-cell malignancies. Common toxicities are myelosuppression, fatigue, diarrhea, skin rash, venous thromboembolism, peripheral neuropathy, and tumor flare reaction. Cardiovascular toxicity has been limited to atrial fibrillation and an increased risk for venous thromboembolism. Autoimmune hemolytic anemia, pneumonitis, and dermatitis have been described with lenalidomide. We propose an immunological mechanism for myocarditis based on the predominantly T-cell infiltration of the myocardium.

Conclusions:

Our findings suggest that lenalidomide may be a cause of drug-induced myocarditis. When patients treated with lenalidomide present with signs and symptoms of heart failure in the absence of other obvious causes, lenalidomide hypersensitivity should be considered in the differential diagnosis and a myocardial biopsy should be considered when other common causes of heart failure have been excluded. A reasonable management approach is drug discontinuation and early institution of corticosteroid therapy. An objective causality assessment, using the Naranjo probability scale, revealed that the adverse drug event was probable.

Differences in antiapoptotic, proliferative activities and morphometry in dilated and ischemic cardiomyopathy: study of hearts explanted from transplant recipients

BACKGROUND

Antiapoptotic as well as replacement and proliferative mechanisms take place in the myocardium in dilated cardiomyopathy (DCM) and ischemic heart disease (IHD). We sought to estimate antiapoptotic, proliferative and replacement activities in cardiomyopathies.

MATERIALS

The study groups included seven hearts with DCM and eight with IHD, which had been explanted at the time of transplantation. The comparator group consisted of cases of myocardial hypertrophy and the control group, donor fragments.

METHODS

Antiapoptotic and proliferative responses were determined immunohistochemically as Bcl-2 and Ki67 expression by semiquantitative assessment of the intensity of staining. We also measured and statistically analyzed the integrative morphometric measurements of the fraction of fibrosis area, the nucleosarcoplasmic ratio, and cardiocyte diameter.

RESULTS

No Bcl-2 expression was observed in the controls. The strongest reaction was seen in the DCM group, then in the IHD, and in the comparator group of myocardial hypertrophy. Proliferative activity was seen only in endocardial and interstitial fibroblasts in DCM and IHD cases. The cardiocyte diameter showed no statistical association between myocardial hypertrophy and IHD, or IHD and DCM, whereas the nucleosarcoplasmic ratios were significantly different from control groups for all comparisons. Myocardial fibrosis showed the highest values in DCM and IHD. Discriminant analysis showed the value of interstitial fibrosis and cardiocyte diameter to categorize the analyzed groups.

CONCLUSIONS

Antiapoptotic Bcl-2 activity seemed to play an important role in cardiocyte preservation, while proliferative activity was resticted to interstitial connective tissue cells as a replacement process. Myocardial Bcl-2 expression, the extent of myocardial fibrosis, and cardiocyte diameter may serve as additional diagnostic tools to differentiate cardiomyopathies.

Do clinical diagnoses correlate with pathological diagnoses in cardiac transplant patients? The importance of endomyocardial biopsy

BACKGROUND

Heart transplantation remains the last treatment option for patients with end-stage cardiac disease. Such diseases include ischemic cardiomyopathy, nonischemic cardiomyopathy and other conditions such as arrhythmogenic right ventricular dysplasia, cardiac sarcoidosis and cardiac amyloidosis.

OBJECTIVE

To review the changes that have occurred over time in the etiology of heart disease in patients requiring heart transplantation, and to compare the clinical and histological diagnoses of explanted hearts from patients with progressive cardiac disease.

METHODS

The pathological findings of 296 surgically excised hearts over a 20-year period (January 1987 to July 2006) at one institution were examined. Patients were separated into groups based on year of heart transplantation. The tissue was examined to determine the underlying cardiac pathology leading to congestive heart failure. Patient records were reviewed for preoperative clinical diagnoses and other relevant data, including pretransplant endomyocardial biopsy (EMB) results, information regarding left ventricular assist devices and, finally, evidence of disease recurrence in the grafted heart.

RESULTS

A shift in the underlying etiology was found in patients who underwent heart transplantation from 1992 to 1996, and 1997 to 2001. Between 1987 and 1997, the majority of transplant cases consisted of ischemic cardiomyopathies. From 1997 to 2001, the majority of patients had nonischemic cardiomyopathies, and this trend continued to 2006. A majority of patients with ischemic and hypertrophic cardiomyopathy were diagnosed correctly (96.5% and 82%, respectively) before transplantation. Most patients diagnosed post-transplant with lymphocytic (viral, 15%), hypersensitive/ eosinophilic (25%) and giant cell (100%) myocarditis, arrhythmogenic right ventricle dysplasia (100%), cardiac sarcoidosis (83%) and iron overload toxicity- associated cardiomyopathy (100%) had been misdiagnosed in pretransplantation investigations. Investigations before transplantation did not include an EMB. Of all 296 patients, 51 patients (17%) were misdiagnosed. Excluding the patients with ischemic cardiomyopathy, 46 of 152 patients (30%) were misdiagnosed before transplantation.

CONCLUSIONS

Although cardiac transplantation is a viable treatment option for patients with a variety of cardiac diseases, accurate diagnosis of patients before transplantation remains a priority. Accurate diagnosis of particular diseases (sarcoidosis, myocarditis, iron toxicity-associated cardiomyopathy and others) allows for proper treatment before transplantation, which may slow down disease progression and improve patient outcomes. Furthermore, it is important to accurately diagnose patients with diseases such as sarcoidosis, amyloidosis and particular types of myocarditis because these can readily recur in the grafted heart. The risk for recurrence must be known to practitioners and, most importantly, to the patient. We strongly recommend the use of EMB if a nonischemic cardiomyopathy is suspected, because the results may alter the diagnosis and modify the treatment strategy.

Cardiac cell-specific apoptotic and cytokine responses to reovirus infection: determinants of myocarditic phenotype

BACKGROUND

The pathophysiologic mechanisms underlying viral myocarditis are not well defined. As a result, effective treatments do not exist and viral myocarditis remains a potentially lethal infection of the heart.

METHODS AND RESULTS

We used cultured rat cardiac myocytes and fibroblasts to investigate apoptosis and cytokine production in response to infection by myocarditic vs. non-myocarditic strains of reovirus. Myocarditic reovirus strain 8B and non-myocarditic strain DB188 replicate comparably in each cardiac cell type. However, strain 8B and related myocarditic reoviruses preferentially increase apoptosis of myocytes relative to fibroblasts, whereas DB188 and nonmyocarditic strains preferentially increase fibroblast apoptosis. Infection of cardiac fibroblasts with the nonmyocarditic strain DB188 elicits substantial increases in a panel of cytokines compared to fibroblasts infected with strain 8B or mock-infected controls. Analysis of culture supernatants using cytometric bead arrays revealed that DB188 enhanced release of interleukin (IL)-1beta, IL-4, IL-6, IL-10, IL-12(p70), GRO-KC, tumor necrosis factor-alpha, and MCP-1 relative to 8B or mock-infected controls (all P < .05).

CONCLUSION

We hypothesize that differential cytokine production and cell-specific apoptosis are important determinants of myocarditic potential of reoviral strains. Therapies that target the beneficial effects of cytokines in limiting cytopathic damage may offer an effective and novel treatment approach to viral myocarditis.

Complication Rate of Right Ventricular Endomyocardial Biopsy via the Femoral Approach

Background— An unequivocal diagnosis of myocarditis and cardiac virus persistence is based on histological, immunohistological, and molecular biological analyses of endomyocardial biopsies (EMBs). Biopsy-based diagnosis of myocarditis has become increasingly important because recent studies have demonstrated the beneficial effects of biopsy-based causal treatment strategies (immunosuppressive or antiviral). Because the risks of major complications caused by EMB procedures have not yet been well defined, we evaluated the incidence of major and minor complications of right ventricular EMB procedures in this retrospective and prospective single-center study.

Methods and Results— With the use of a modified Cordis bioptome, 1919 patients underwent 2505 EMB procedures retrospectively over a 9-year period (January 1995 to December 2003), and 496 patients underwent 543 EMB procedures prospectively between January 2004 and December 2005. A total of 2415 patients had 3048 EMB procedures via the right femoral vein approach under biplane fluoroscopic control to evaluate unexplained left ventricular dysfunction (retrospective left ventricular ejection fraction, 49.8±18.8%; prospective, 48.8±19.7%) after exclusion of secondary causes. During each EMB procedure, an average of 8.2±0.8 EMBs were obtained retrospectively and 10.1±0.6 specimens prospectively for a total of 26 025 specimens. No patient died or required emergency cardiac surgery. Other major complications like cardiac tamponade requiring pericardiocentesis or complete atrioventricular block requiring permanent pacing were very rare: 0.12% in the retrospective study and 0% in the prospective study. Minor complications such as pericardial effusion, conduction abnormalities, or arrhythmias occurred in 0.20% of the EMB procedures in the retrospective study and 5.5% in the prospective study.

Conclusions— The EMB procedure via the femoral vein approach under fluoroscopic guidance has a very low complication rate when performed by experienced operators.

Complex multidrug therapy in a patient with pulmonary hypertension before and after orthotopic heart transplantation. A case report

Pulmonary arterial hypertension represents an absolute contraindication for heart transplantation. We report the case of a 30-year-old man with end-stage heart failure due to restrictive cardiomyopathy and pulmonary arterial hypertension. A complex multidrug therapy improved pulmonary haemodynamics to the point that orthotopic heart transplantation could be carried out. At 18-month follow-up after heart transplantation, the patient's cardiac function made a full recovery. Larger prospective studies are warranted to support these results.

Myocarditis

Myocarditis represents a heterogeneous final common pathway for myocardial inflammation of diverse etiologies and accounts for up to one-third of cases of dilated cardiomyopathy. The pathophysiology of viral myocarditis can be disaggregated into the effects of direct viral mediated injury, triggered acute and chronic autoimmune responses, and subsequent adverse remodeling. Recent research highlights the pathogenic role of persistent viral genome expression, Fas-ligand, tumor necrosis factor-alpha receptor 1, and antimyosin autoantibodies in the evolution of chronic systolic and diastolic heart failure. Recent refinements in endomyocardial biopsy evaluation, cardiac magnetic resonance imaging, and cytokine assays augment existing diagnostic modalities. Novel specific immunosuppressive targets aimed at interrupting myocyte injury and apoptosis, including interferon-beta seem promising to date in small clinical studies performed on selected patients.

Myocyte diameter and fractional area of collagen are not associated with survival time of outpatients with idiopathic dilated cardiomyopathy: A study based on right ventricular endomyocardial biopsies

Morphometric data obtained from the analysis of endomyocardial biopsy might be useful to evaluate prognosis of patients with dilated cardiomyopathy. We measured the myocyte diameter, its coefficient of variation and the fractional area of collagen in right ventricular endomyocardial biopsies of 35 outpatients with idiopathic dilated cardiomyopathy. None of the evaluated histological parameter was associated with the survival time of the patients (range: 2 to 5588; median: 706 days). Right ventricular endomyocardial biopsy should not be indicated to predict evolution or fatal outcome in patients with idiopathic dilated cardiomyopathy.

Peripartum cardiomyopathy

Peripartum cardiomyopathy (PPCM) is a disorder in which initial left ventricular systolic dysfunction and symptoms of heart failure occur between the late stages of pregnancy and the early postpartum period. It is common in some countries and rare in others. The causes and pathogenesis are poorly understood. Molecular markers of an inflammatory process are found in most patients. Clinical presentation includes usual signs and symptoms of heart failure, and unusual presentations relating to thromboembolism. Clinicians should consider PPCM in any peripartum patient with unexplained disease. Conventional heart failure treatment includes use of diuretics, beta blockers, and angiotensin-converting enzyme inhibitors. Effective treatment reduces mortality rates and increases the number of women who fully recover left ventricular systolic function. Outcomes for subsequent pregnancy after PPCM are better in women who have first fully recovered heart function. Areas for future research include immune system dysfunction, the role of viruses, non-conventional treatments such as immunosuppression, immunoadsorption, apheresis, antiviral treatment, suppression of proinflammatory cytokines, and strategies for control and prevention.

Endomyocardial biopsy - jugular/subclavian vein approach

Endomyocardial biopsy (EMB) is a diagnostic procedure mainly to survey the sufficiency of immunosuppressive therapy after cardiac transplantation. Other indications for EMB remain controversial. After insertion of an introducer sheet in Seldinger's technique, four to six biopsies are taken from the right ventricle by fluoroscopic guidance. EMB is a very safe operation with a low complication rate which can be rapidly performed with little inconvenience for the patient if performed by a skilled surgeon.