Right ventricular dysfunction: an independent predictor of adverse outcome in patients with myocarditis

Different prognostic value of functional right ventricular parameters in arrhythmogenic right ventricular cardiomyopathy/dysplasia

BACKGROUND

The value of standard 2-dimensional transthoracic echocardiographic parameters for risk stratification in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is controversial.

METHODS AND RESULTS

We investigated the impact of RV fractional area change (FAC) and tricuspid annulus plane systolic excursion (TAPSE) for the prediction of major adverse cardiovascular events (MACE) defined as the occurrence of cardiac death, heart transplantation, survived sudden cardiac death, ventricular fibrillation, sustained ventricular tachycardia, or arrhythmogenic syncope. Among 70 patients who fulfilled the 2010 ARVC/D Revised Task Force Criteria and underwent baseline transthoracic echocardiography, 37 (53%) patients experienced MACE during a median follow-up period of 5.3 (interquartile range, 1.8-9.8) years. Average values for FAC, TAPSE, and TAPSE indexed to body surface area (BSA) decreased over time (P=0.03 for FAC, P=0.03 for TAPSE, and P=0.01 for TAPSE/BSA, each versus baseline). In contrast, median RV end-diastolic area increased (P=0.001 versus baseline). Based on the results of Kaplan-Meier estimates, the time between baseline transthoracic echocardiography and experiencing MACE was significantly shorter for patients with FAC <23% (P<0.001), TAPSE <17 mm (P=0.02), or right atrial short axis/BSA ≥25 mm/m(2) (P=0.04) at baseline. A reduced FAC constituted the strongest predictor of MACE (hazard ratio, 1.08 per 1% decrease; 95% confidence interval, 1.04-1.12; P<0.001) on bivariable analysis.

CONCLUSIONS

This long-term observational study indicates that TAPSE and dilation of right-sided cardiac chambers are associated with an increased risk for MACE in patients with ARVC/D with advanced disease and a high risk for adverse events. However, FAC is the strongest echocardiographic predictor of adverse outcome in these patients. Our data advocate a role for transthoracic echocardiography in risk stratification in patients with ARVC/D, although our results may not be generalizable to lower-risk ARVC/D cohorts.

Role of endomyocardial biopsy for children presenting with acute systolic heart failure

Myocarditis, an inflammatory disease of the heart, frequently results from viral infections, postviral immune-mediated responses, or both. It is a common cause of acute-onset systolic heart failure in children. Endomyocardial biopsy (EMB) remains the gold standard for the diagnosis of myocarditis. However, EMB is not performed for most myocarditis cases involving children in the United States. Clinical scenarios in which EMB results added unique prognostic data and guidance to therapy have been defined recently. This review outlines the role of EMB in the diagnosis and management of myocarditis for children presenting with acute-onset systolic heart failure.

Role of CMR imaging in risk stratification for sudden cardiac death

Left ventricular ejection fraction as determined by echocardiography has a limited sensitivity in predicting risk for sudden cardiac death (SCD). Subsequent efforts to improve cost-effectiveness of device implantation and identify a better risk-stratifying tool have been quite desirable. The presence of scar and myocardial tissue heterogeneity has been linked to ventricular arrhythmia, which is believed to be the major cause of SCD. Cardiac magnetic resonance is a noninvasive imaging modality that visualizes and quantifies scar, with growing evidence delineating its additive value in identifying patients at higher risk for SCD.

Assessment and Prognostic Relevance of Right Ventricular Contractile Reserve in Patients With Severe Pulmonary Hypertension

Background—

This study sought to analyze a new approach to assess exercise-induced pulmonary artery systolic pressure (PASP) increase by means of stress Doppler echocardiography as a possible measure of right ventricular contractile reserve in patients with severe pulmonary hypertension and right heart failure.

Methods and Results—

In this prospective study, patients with invasively diagnosed pulmonary arterial hypertension or inoperable chronic thromboembolic pulmonary hypertension and impaired right ventricular pump function despite a stable targeted pulmonary arterial hypertension medication underwent a broad panel of noninvasive assessments, including stress echocardiography and cardiopulmonary exercise testing. On the basis of the assumption that exercise-induced PASP is a measure of right ventricular contractile reserve, patients were classified into 2 groups according to an exercise-induced PASP increase above or below the median. Patients were followed up for 3.0±1.8 years. Univariate and multivariate analyses were used for factors predicting survival. Of 124 patients, 66 were below the median exercise-induced PASP increase of 30 mm Hg (low PASP), and 58 patients were above the median (high PASP). These groups were not significantly different in terms of medication and resting hemodynamics. Low PASP was associated with a significantly lower 6-minute walking distance, peak o 2 per kilogram, and 1-, 3-, and 4-year survival rates (92%, 69%, and 48%, respectively, versus 96%, 92%, and 89%). In the multivariate Cox model analysis adjusted for age and sex, PASP increase during exercise and peak o 2 per kilogram remained independent prognostic markers (hazard ratio, 2.56 for peak o 2 per kilogram and 2.84 for PASP increase).

Conclusions—

Exercise-induced PASP increase is of high clinical and prognostic relevance in pulmonary hypertension patients and may indicate right ventricular contractile reserve. Stress Doppler echocardiography may be a useful tool for prognostic assessment in pulmonary hypertension patients.

The right ventricle: biologic insights and response to disease: updated

Despite ample evidence that right ventricular function is a critical determinant of the clinical response to a spectrum of cardiovascular diseases, there has been only a limited analysis of the unique and distinguishing physiologic properties of the RV under normal circumstances and in response to pathologic insults. This knowledge deficit is increasingly acknowledged. This review highlights some of these features and underscores the fact that rational therapy in RV failure needs to acknowledge its unique physiology and ought to be chamber specific. That is proven therapies for LV dysfunction do not necessarily apply to the RV. The updated version of this review now acknowledges recent advances in the understanding of metabolic, inflammatory and gender-specific influences on the right ventricle.

Pericarditis, myocarditis, and other cardiomyopathies

An overview of pericarditis, cardiomyopathy, and acute myocarditis is presented. Clinical presentation, causes, physical signs, laboratory testing, and various imaging procedures are discussed. Established pharmacologic and mechanical therapies are reviewed. Short-term and long-term prognoses, when relevant, are discussed.

Salmonella enteritidis induced myocarditis in a 16-year-old girl

Myocarditis typically presents with non-specific clinical symptoms, and can easily be missed in the absence of a high index of clinical suspicion. Myocarditis caused by bacterial pathogens is rare in immunocompetent individuals, more commonly seen following viral infection. Although more classically associated with typhoid fever and gastroenteritis, Salmonella species are a rare cause of myocarditis. We report a case of Salmonella enteritidis-induced myocarditis after gastrointestinal infection in a 16 year-old girl, and discuss the diagnostic tools currently utilised to ascertain the diagnosis.

[Myocarditis: magnetic resonance imaging diagnosis and follow-up]

Myocarditis, inflammation of the myocardium, is usually due to viral infection. Diagnostic confirmation in ordinary clinical practice is difficult because the findings on the clinical history, physical examination, electrocardiogram, and laboratory tests offer scant diagnostic accuracy, and the differential diagnosis is often done with acute myocardial infarction. Cardiac magnetic resonance imaging (CMR) has become the method of choice for the diagnosis of myocarditis. In this article, we describe the CMR findings at diagnosis and during the follow-up of patients with myocarditis, the differential diagnosis with other acute processes like myocardial infarction, and the prognostic factors studied with CMR.

Republished: pathogenesis and diagnosis of myocarditis

Acute myocarditis is an inflammatory disease of the heart muscle that may progress to dilated cardiomyopathy and chronic heart failure. A number of factors including the sex hormone testosterone, components of innate immunity, and profibrotic cytokines have been identified in animal models as important pathogenic mechanisms that increase inflammation and susceptibility to chronic dilated cardiomyopathy. The clinical presentation of acute myocarditis is non-specific and mimics more common causes of heart failure and arrhythmias. Suspected myocarditis is currently confirmed using advanced non-invasive imaging and histopathologic examination of heart tissue. However, the diverse presentations of myocarditis and the lack of widely available, safe, and accurate non-invasive diagnostic tests remain major obstacles to early diagnosis and population based research. Recent advances in the understanding of disease pathogenesis described in this review should lead to more accurate diagnostic algorithms and non-invasive tests.

Cardiac MRI assessment of right ventricular function in acquired heart disease: factors of variability

RATIONALE AND OBJECTIVES

To evaluate intra- and inter-observer variability of right ventricular (RV) functional parameters as evaluated by cardiac magnetic resonance imaging (MRI) in patients with acquired heart disease (AHD), and to identify factors associated with an increased variability.

MATERIALS AND METHODS

Sixty consecutive patients were enrolled. Right and left ventricular (LV) volumes, ejection fraction, and mass were determined from short-axis cine sequences. All analyzes were performed twice by three observers with various training-degree in cardiac MRI. Intra- and inter-observer variability was evaluated. The impact on variability of each of the following parameters was assessed: observer's experience, basal and apical slices selection, end-systolic phase selection, and delineation.

RESULTS

Mean segmentation time ranged 9.8-19.0 minutes for RV and 6.4-9.2 minutes for LV. Variability of RV functional parameters measurement was strongly influenced by previous observer's experience: it was two to three times superior to that of LV, even for the most experienced observer. High variability in the measurement of RV mass was observed. For both ventricles, selection of the basal slice and delineation were major determinants of variability.

CONCLUSION

As compared to LV, RV function assessment with cardiac MRI in AHD patients is much more variable and time-consuming. Observer's experience, selection of basal slice, and delineation are determinant.

Speckle tracking echocardiography in acute myocarditis

To evaluate 2-dimensional speckle tracking echocardiography as a diagnostic and prognostic tool in patients with acute myocarditis. In this retrospective cohort study, 45 patients (age, 39 ± 15 years; 32 male) with suspected acute myocarditis and 83 healthy controls (age, 39 ± 13 years; 27 male) underwent 2-dimensional speckle tracking echocardiography. Main outcome measures were circumferential and longitudinal strain and strain rate as prognostic and diagnostic markers. Patients with myocarditis had lower circumferential strain (-13.3 ± 5.6 % vs. -22.3 ± 4 %), circumferential strain rate (-0.9 ± 0.3 vs. -1.4 ± 0.3 s(-1)), longitudinal strain (-11.7 ± 4 % vs. -17.7 ± 1.9 %), and longitudinal strain rate (-0.7 ± 0.2 vs. -1.0 ± 0.1 s(-1)) (all P < .001). For diagnostic purposes, longitudinal strain had the greatest area under the curve, 0.93 (optimal cutoff value, -15.1 %; sensitivity, 78 %; specificity, 93 %). Future events were defined as cardiac death, heart transplant, placement of left ventricular assist device or implantable cardioverter-defibrillator, pulmonary edema-related respiratory failure, cardiogenic shock, and rehospitalization due to cardiac events. For every 1 % decline in longitudinal or circumferential strain, the hazard ratios (95 % CIs) were 1.26 (1.10-1.47) and 1.34 (1.14-1.63), respectively; for every 0.1 s(-1) decline in longitudinal or circumferential strain rate, the hazard ratios (95 % CIs) were 1.43 (1.09-1.89) and 1.52 (1.19-2.01), respectively (P < .01). Kaplan-Meier curve and log-rank test showed event-free survival significantly related to these 4 measurements. In acute myocarditis, left ventricular strain and strain rate may be promising diagnostic and prognostic tools, even in patients with preserved left ventricular ejection fraction. Most importantly, this imaging technique had a role in predicting deterioration and overall event-free survival.

Myocarditis

Myocarditis is an underdiagnosed cause of acute heart failure, sudden death, and chronic dilated cardiomyopathy. In developed countries, viral infections commonly cause myocarditis; however, in the developing world, rheumatic carditis, Trypanosoma cruzi, and bacterial infections such as diphtheria still contribute to the global burden of the disease. The short-term prognosis of acute myocarditis is usually good, but varies widely by cause. Those patients who initially recover might develop recurrent dilated cardiomyopathy and heart failure, sometimes years later. Because myocarditis presents with non-specific symptoms including chest pain, dyspnoea, and palpitations, it often mimics more common disorders such as coronary artery disease. In some patients, cardiac MRI and endomyocardial biopsy can help identify myocarditis, predict risk of cardiovascular events, and guide treatment. Finding effective therapies has been challenging because the pathogenesis of chronic dilated cardiomyopathy after viral myocarditis is complex and determined by host and viral genetics as well as environmental factors. Findings from recent clinical trials suggest that some patients with chronic inflammatory cardiomyopathy have a progressive clinical course despite standard medical care and might improve with a short course of immunosuppression.

The right ventricle: biologic insights and response to disease

Despite ample evidence that right ventricular function is a critical determinant of the clinical response to a spectrum of cardiovascular diseases, there has been only a limited analysis of the unique and distinguishing physiologic properties of the RV under normal circumstances and in response to pathologic insults. This review highlights some of these features and underscores the fact that rational therapy in RV failure should acknowledge this physiology and ought to be chamber specific.

The management of myocarditis

Despite considerable advances in our understanding of myocarditis pathogenesis, the clinical management of myocarditis has changed relatively little in the last few years. This review aims to help bridge the widening gap between recent mechanistic insights, which are largely derived from animal models, and their potential impact on disease burden. We illustrate the pathogenetic mechanisms that are prime targets for novel therapeutic interventions. Pathway and pathogen-specific molecular diagnostic tests have expanded the role for endomyocardial biopsy. State of the art cardiac magnetic resonance imaging can now provide non-invasive tissue characterization and localize inflammatory infiltrates but imaging techniques are misleading if infectious agents are involved. We emphasize the gaps in our current clinical knowledge, particularly with respect to aetiology-based therapy, and suggest opportunities for high impact, translational investigations.

The evolving approach to paediatric myocarditis: a review of the current literature

Paediatric myocarditis remains challenging from the perspectives of diagnosis and management. Multiple aetiologies exist and the majority of cases appear to be related to viral illnesses. Enteroviruses are believed to be the most common cause, although cases related to adenovirus may be more frequent than suspected. The clinical presentation is extremely varied, ranging from asymptomatic to sudden unexpected death. A high index of suspicion is crucial. There is emerging evidence to support investigations such as serum N-terminal B-type natriuretic peptide levels, as well as cardiac magnetic resonance imaging as adjuncts to the clinical diagnosis. In the future, these may reduce the necessity for invasive methods, such as endomyocardial biopsy, which remain the gold standard. Management generally includes supportive care, consisting of cardiac failure medical management, with the potential for mechanical support and cardiac transplantation. Treatments aimed at immunosuppression remain controversial. The paediatric literature is extremely limited with no conclusive evidence to support or refute these strategies. This article summarises the current literature regarding aetiology, clinical presentation, diagnosis, and management of myocarditis in paediatric patients.

Biochemical and myofilament responses of the right ventricle to severe pulmonary hypertension

Right ventricular (RV) failure is one of the strongest predictors of mortality both in the presence of left ventricular decompensation and in the context of pulmonary vascular disease. Despite this, there is a limited understanding of the biochemical and mechanical characteristics of the pressure-overloaded RV at the level of the cardiac myocyte. To better understand this, we studied ventricular muscle obtained from neonatal calves that were subjected to hypobaric atmospheric conditions, which result in profound pulmonary hypertension. We found that RV pressure overload resulted in significant changes in the phosphorylation of key contractile proteins. Total phosphorylation of troponin I was decreased with pressure overload, predominantly reflecting changes at the putative PKA site at Ser(22/23). Similarly, both troponin T and myosin light chain 2 showed a significant decline in phosphorylation. Desmin was unchanged, and myosin-binding protein C (MyBP-C) phosphorylation was apparently increased. However, the apparent increase in MyBP-C phosphorylation was not due to phosphorylation but rather to an increase in MyBP-C total protein. Importantly, these findings were seen in all regions of the RV and were paralleled by reduced Ca(2+) sensitivity with preserved maximal Ca(2+) saturated developed force normalized to cross-sectional area in isolated skinned right ventricular myocyte fragments. No changes in total force or cooperativity were seen. Taken together, these results suggest that RV failure is mechanistically unique from left ventricular failure.

Diagnostic accuracy and variability of three semi-quantitative methods for assessing right ventricular systolic function from cardiac MRI in patients with acquired heart disease

OBJECTIVES

To evaluate the diagnostic accuracy and variability of 3 semi-quantitative (SQt) methods for assessing right ventricular (RV) systolic function from cardiac MRI in patients with acquired heart disease: tricuspid annular plane systolic excursion (TAPSE), RV fractional-shortening (RVFS) and RV fractional area change (RVFAC).

METHODS

Sixty consecutive patients were enrolled. Reference RV ejection fraction (RVEF) was determined from short axis cine sequences. TAPSE, RVFS and RVFAC were measured on a 4-chamber cine sequence. All SQt analyses were performed twice by 3 observers with various degrees of training in cardiac MRI. Correlation with RVEF, intra- and inter-observer variability, and receiver operating characteristic (ROC) curve analysis were performed for each SQt method.

RESULTS

Correlation between RVFAC and RVEF was good for all observers and did not depend on previous cardiac MRI experience (R range = 0.716-0.741). Conversely, RVFS (R range = 0.534-0.720) and TAPSE (R range = 0.482-0.646) correlated less with RVEF and depended on previous experience. Intra- and inter-observer variability was much lower for RVFAC than for RVFS and TAPSE. ROC analysis demonstrated that RVFAC <41% could predict a RVEF <45% with 90% sensitivity and 94% specificity.

CONCLUSIONS

RVFAC appears to be more accurate and reproducible than RVFS and TAPSE for SQt assessment of RV function by cardiac MRI.

Peripartum cardiomyopathy

Peripartum cardiomyopathy (PPCM) is a potentially devastating disease that affects women during the last months of pregnancy or the first months after delivery. The aetiology and pathogenesis of this disease remain unclear, but oxidative stress and the generation of a cardiotoxic fragment of prolactin may play key roles. Diagnosing PPCM remains a challenge, as symptoms may mimic those women experience during normal pregnancy and the peripartum period. A high index of suspicion is thus necessary to make the diagnosis. Patients with PPCM have a varied clinical course, as some patients achieve full recovery while others progress to end-stage heart failure and even death. Standard heart failure treatment is indicated, although special provisions are necessary in pregnant and lactating women. Additional research into the pathophysiology of this disease, including possible genetic contributions, may lead to novel treatment strategies that can improve outcomes.

Late tricuspid surgery: predicting outcome with computed tomography

Tricuspid regurgitation can progressively worsen years after left-sided heart valve surgery, requiring surgical intervention for which the prognostic factors are unclear. This study aimed to assess the prediction of surgical outcome using right ventricular function obtained from computed tomography. We prospectively enrolled 24 patients who underwent isolated tricuspid repair or replacement from 2005 to 2008. Right ventricular computed tomography was carried out before surgery. The primary endpoint was survival with symptomatic improvement after one year. Twelve patients survived with improvement of at least one New York Heart Association functional class, and 12 died or had no symptomatic improvement. All baseline characteristics, echocardiogram data, and surgical details were similar in both groups. Right ventricular computed tomography parameters including end-systolic volume, indexed end-systolic volume, end-diastolic volume, and indexed end-diastolic volume were significantly different between the two groups. We concluded that right ventricular function assessed by computed tomography can predict the surgical outcome in patients undergoing surgery for isolated late tricuspid regurgitation.

Imaging spectrum of sudden athlete cardiac death

Sudden athlete death (SAD) is a widely publicized and increasingly reported phenomenon. For many, the athlete population epitomize human physical endeavour and achievement and their unexpected death comes with a significant emotional impact on the public. Sudden deaths within this group are often without prior warning. Preceding symptoms of exertional syncope and chest pain do, however, occur and warrant investigation. Similarly, a positive family history of sudden death in a young person or a known family history of a condition associated with SAD necessitates further tests. Screening programmes aimed at detecting those at risk individuals also exist with the aim of reducing fatalities. In this paper we review the topic of SAD and discuss the epidemiology, aetiology, and clinical presentations. We then proceed to discuss each underlying cause, in turn discussing the pathophysiology of each condition. This is followed by a discussion of useful imaging methods with an emphasis on cardiac magnetic resonance and cardiac computed tomography and how these address the various issues raised by the pathophysiology of each entity. We conclude by proposing imaging algorithms for the investigation of patients considered at risk for these conditions and discuss the various issues raised in screening.

Assessment of right ventricular systolic function: comparison between cardiac magnetic resonance derived ejection fraction and pulsed-wave tissue Doppler imaging of the tricuspid annulus

BACKGROUND

Systolic right ventricular (RV) function is an important predictor in the course of various congenital and acquired heart diseases. Its practical determination by echocardiography remains challenging. We compared routine assessment of lateral tricuspid annular systolic motion velocity (TV(lat), cm/s) using pulsed-wave tissue Doppler imaging from the apical 4-chamber view with cardiac magnetic resonance (CMR) as reference method.

METHODS AND RESULTS

254 individuals (43 ± 18 years) underwent both CMR (contiguous short axis slices; retrogated cine steady state free precession technique; manual contour tracing) and echocardiography within 2 ± 2 months. Seventy-five had coronary artery disease, 87 congenital heart disease, 17 dilated cardiomyopathy, 15 pulmonary artery hypertension, and 47 normal findings. RV ejection fraction (EF) by CMR was 51 ± 12% (range 17-78%). There was a linear correlation between RVEF and TV(lat) (r=0.60; p<0.0001). A TV(lat) cut-off of 12 cm/s identified patients with normal EF (≥50%) with 81% sensitivity and 68% specificity, and a threshold of TV(lat) <9 cm/s identified patients with severely reduced RVEF (<30%) with 82% sensitivity and 86% specificity.

CONCLUSIONS

Systolic long-axis velocity measurements of the lateral tricuspid annulus allow a reliable assessment of RVEF in clinical routine. A threshold of TV(lat)<9 cm/s identifies patients with severely reduced RVEF (<30%) with high sensitivity and specificity.

Myocarditis

Myocarditis is an uncommon, potentially life-threatening disease that presents with a wide range of symptoms in children and adults. Viral infection is the most common cause of myocarditis in developed countries, but other etiologies include bacterial and protozoal infections, toxins, drug reactions, autoimmune diseases, giant cell myocarditis, and sarcoidosis. Acute injury leads to myocyte damage, which in turn activates the innate and humeral immune system, leading to severe inflammation. In most patients, the immune reaction is eventually down-regulated and the myocardium recovers. In select cases, however, persistent myocardial inflammation leads to ongoing myocyte damage and relentless symptomatic heart failure or even death. The diagnosis is usually made based on clinical presentation and noninvasive imaging findings. Most patients respond well to standard heart failure therapy, although in severe cases, mechanical circulatory support or heart transplantation is indicated. Prognosis in acute myocarditis is generally good except in patients with giant cell myocarditis. Persistent, chronic myocarditis usually has a progressive course but may respond to immunosuppression.

Right ventricular dysfunction predicts poor outcome following hemodynamically compromising rejection

BACKGROUND

Hemodynamically compromising rejection (HCR) is a major cause of mortality and morbidity after heart transplantation. Right ventricular (RV) function is a strong predictor of outcome in patients with heart failure and myocarditis. The objective of the current study is to determine whether RV dysfunction predicts event-free survival in patients with HCR.

METHODS

Medical records of 548 heart transplant patients followed at Stanford University between January 1998 and January 2007 were reviewed. HCR was defined as a rejection episode requiring hospitalization for heart failure. Univariate and multivariate analyses were performed to identify risk factors for death or retransplantation at 1 year.

RESULTS

HCR occurred in 71 patients (12.9%). Death or retransplantation at 1 year occurred in 28 patients (39%). Univariate analysis identified non-cellular rejection (odds ratio [OR] = 3.20, p = 0.021), the need for inotropic support (OR = 4.80, p = 0.007), RV dysfunction (OR = 4.63, p = 0.006), left ventricular ejection fraction (OR = 0.941, p = 0.031) and acute renal failure (OR = 3.82, p = 0.010) as predictors of death or retransplantation at 1 year. Multivariate analysis identified RV dysfunction (OR = 4.80, p = 0.007) and the need for inotropic support (OR = 5.00, p = 0.009) as predictors of death or retransplantation at 1 year.

CONCLUSIONS

In the modern era of immunosuppression, HCR remains a major complication after heart transplantation. RV dysfunction was identified as a novel risk factor for death or retransplantation following HCR.

Non-invasive imaging in the diagnosis of acute viral myocarditis

Autopsy series of consecutive cases have demonstrated an incidence of myocarditis at approximately 1–10%; on the contrary, myocarditis is seriously underdiagnosed clinically. In a traditional view, the gold standard has been myocardial biopsy. However, it is generally specific but invasive and less sensitive, mostly because of the focal nature of the disease. Thus, non-invasive approaches to detect myocarditis are necessary. The traditional diagnostic tools are electrocardiography, laboratory values, especially troponin T or I, creatine kinase and echocardiography. For a long period, nuclear technique with indium-111 antimyosin antibody has been used as a diagnostic approach. In the last years, the use of this technique has declined because of radiation exposure and 48-h delay in obtaining imaging after injection to prevent blood pool effect. Thus, a non-invasive diagnostic approach without radiation and online image availability has been awaited. Cardiac magnetic resonance imaging has these promising characteristics. With this technique, it is possible to analyse inflammation, oedema and necrosis in addition to functional parameters such as left ventricular function, regional wall motion and dimensions. Thus, cardiovascular magnetic resonance imaging has emerged as the most important imaging tool in the diagnostic procedure and the review focus on this field. But there are also advances in echocardiography and computer tomography, which are described in detail.

Myocarditis

Myocarditis may present with a wide range of symptoms, ranging from mild dyspnea or chest pain that resolves without specific therapy to cardiogenic shock and death. Dilated cardiomyopathy with chronic heart failure is the major long-term sequela of myocarditis. Most often, myocarditis results from common viral infections; less commonly, specific forms of myocarditis may result from other pathogens, toxic or hypersensitivity drug reactions, giant-cell myocarditis, or sarcoidosis. The prognosis and treatment of myocarditis vary according to the cause, and clinical and hemodynamic data usually provide guidance to decide when to refer a patient to a specialist for endomyocardial biopsy. The aim of this review is to provide a practical and current approach to the evaluation and treatment of suspected myocarditis.

[Role of right heart failure in cardiac resynchronization]

During recent years cardiac resynchronization has become an important tool in the treatment of patients with signs and symptoms of heart failure and desynchronized contraction of the left ventricle. Among patients with heart failure, right ventricular involvement can occur because the underlying disease affects both ventricles or because the reduction of left ventricular function impairs the right ventricular function by altered coupling and increased right ventricular afterload. Irrespective of the underlying cause the reduction of right ventricular function confers an adverse prognosis that is further aggravated by the presence of pulmonary hypertension. The present article describes the relevance of reduced right ventricular function for the clinical syndrome of heart failure, the role of right ventricular resynchronization in patients with predominant right heart failure and the possible effects of left ventricular resynchronization on a preexisting impairment of right ventricular function.

Fulminant myocarditis

Fulminant myocarditis is an inflammatory process that occurs in the myocardium and causes acute-onset heart failure. If patients with fulminant myocarditis are aggressively supported in a timely manner, nearly all can have an excellent recovery. In this Review, we discuss the clinical and histological distinguishing features of fulminant myocarditis and contrast this disease entity with nonfulminant myocarditis. The epidemiology, pathophysiology, clinical presentation, methods of diagnosis, management options and prognosis of fulminant myocarditis are reviewed in detail.

Accuracy of guideline recommendations for two-dimensional quantification of the right ventricle by echocardiography

BACKGROUND

The accuracy of the guidelines of the American Society of Echocardiography (ASE) for the two-dimensional (2D) quantitative assessment of right ventricular (RV) size and function has not been evaluated against MRI-derived RV volumes in patients with congenital heart disease and RV volume overload.

METHODS

Three groups of patients were studied: a normal RV group (Group I, n = 31), a repaired tetralogy of Fallot group (Group II, n = 33), and an unrepaired atrial septal defect and/or partially anomalous pulmonary venous connection group (Group III, n = 23). Recommended 2D linear and cross-sectional area measurements were made on clinical echocardiographic and MRI studies performed less than 6 months apart.

RESULTS

Most 2D RV parameters were smaller by echocardiography versus MRI. There was weak correlation between 2D RV measurements by echocardiography and MRI-derived RV volumes (Group I: r = 0.15-0.54, Group II: r = 0.33-0.61, Group III: r = 0.32-0.85), and only modest improvement when the same 2D measurements were performed by MRI (Group I: r = 0.37-0.61, Group II: r = 0.44-0.69, Group III: r = 0.28-0.74). The difference between 2D RV measurements by echocardiography and MRI-derived RV volumes was more pronounced in the RV volume overload groups.

CONCLUSIONS

The correlation between currently recommended 2D RV measurements by echocardiography and MRI-derived RV volumes was weak, and improved only modestly when MRI was used to make the same 2D measurements. Moreover, 2D echocardiographic assessment of the RV appears to be less accurate in patients with congenital heart disease and a dilated RV.

Myocarditis

Viruses are the most common cause of myocarditis in economically advanced countries.

Enteroviruses and adenoviruses are the most common etiologic agents.

Viral myocarditis is a triphasic process. Phase 1 is the period of active viral replication in the myocardium during which the symptoms of myocardial damage range from none to cardiogenic shock. If the disease process continues, it enters phase 2, which is characterized by autoimmunity triggered by viral and myocardial proteins. Heart failure often appears for the first time in phase 2. Phase 3, dilated cardiomyopathy, is the end result in some patients. Diagnostic procedures and treatment should be tailored to the phase of disease.

Viral myocarditis is a significant cause of dilated cardiomyopathy, as proved by the frequent presence of viral genomic material in the myocardium, and by improvement in ventricular function by immunomodulatory therapy.

Myocarditis of any etiology usually presents with heart failure, but the second most common presentation is ventricular arrhythmia. As a result, myocarditis is one of the most common causes of sudden death in young people and others without preexisting structural heart disease.

Myocarditis can be definitively diagnosed by endomyocardial biopsy. However, it is clear that existing criteria for the histologic diagnosis need to be refined, and that a variety of molecular markers in the myocardium and the circulation can be used to establish the diagnosis.

Treatment of myocarditis has been generally disappointing. Accurate staging of the disease will undoubtedly improve treatment in the future. It is clear that immunosuppression and immunomodulation are effective in some patients, especially during phase 2, but may not be as useful in phases 1 and 3. Since myocarditis is often selflimited, bridging and recovery therapy with circulatory assistance may be effective. Prevention by immunization or receptor blocking strategies is under development.

Giant cell myocarditis is an unusually fulminant form of the disease that progresses rapidly to heart failure or sudden death. Rapid onset of disease in young people, especially those with other autoimmune manifestations, accompanied by heart failure or ventricular arrhythmias, suggests giant cell myocarditis.

Peripartum cardiomyopathy in economically developed countries is usually the result of myocarditis.

Noninvasive imaging in myocarditis

Increased recognition of the role of inflammation in acute and chronic dilated cardiomyopathy has revived an interest in noninvasive imaging for detection of myocarditis. Diagnostic strategies that are based on molecular imaging promise to further advance our understanding and improve diagnostic precision. This article reviews the strengths and limitations of common clinical tests used for the diagnosis of myocarditis, with a focus on the emerging role of cardiovascular magnetic resonance imaging. Novel imaging modalities that are currently in preclinical development are discussed with recommendations for future clinical research.

Comparison of right ventricular functions by tissue Doppler imaging in patients with obstructive sleep apnea syndrome with or without hypertension

OBJECTIVE

To evaluate the right ventricular function in patients with obstructive sleep apnea syndrome (OSAS) independent from systemic hypertension (HT) and to determine the association between OSAS severity and right ventricular dysfunction.

METHODS

The study population included 77 consecutive subjects; 20 of these patients had OSAS, 20 of them had HT, but did not have OSAS, 16 patients, who constituted the study group, had both disorders, and 21 subjects without any of these two disorders represented the control group. Right ventricular function was assessed by echocardiography: standard two-dimensional, M-Mode, and conventional Doppler as well as tissue Doppler imaging. None of the patients had a previous history of cardiac disease. The diagnosis of OSAS was based on an apnea- hipopnea index of 5 or higher in polysomnography.

RESULTS

Tricuspid inflow velocities and tissue Doppler derived tricuspid annular diastolic velocities were significantly different in the patient groups (OSAS, HT, OSAS + HT) compared to the control group. Tricuspid annular plane systolic excursion (TAPSE) (18.3 +/- 3.2, 18.4 +/- 2.5, 20.1 +/- 2.1, and 20.7 +/- 2.5 mm, respectively, P = 0.024) and peak systolic myocardial velocity at tricuspid lateral annulus (S-vel) (12.2 +/- 1.5, 10.9 +/- 0.9, 11.2 +/- 1.1, and 13.1 +/- 2.1 cm/s, respectively, P < 0.001) were significantly lower in patient groups compared to those of the study group. Tissue Doppler derived myocardial performance index (MPI) of the right ventricle was significantly impaired in the patient groups compared to the control group (0.34 +/- 0.06, 0.44 +/- 0.06, 0.45 +/- 0.07, and 0.41 +/- 0.06, respectively, P < 0.001). With regard to these right ventricular functional parameters, there was no significant difference between OSAS and the other patient groups (HT and OSAS + HT). There were significant correlations both between OSAS severity and the right ventricular functions, and between diastolic and systolic parameters of the right ventricle (r = -0.45, P < 0.05).

CONCLUSION

Both right ventricular systolic and diastolic functions are impaired in patients having OSAS with or without HT. Right ventricular MPI was found to be the parameter most closely related with OSAS severity and the right ventricular subclinical dysfunction.

Severe tricuspid regurgitation shows significant impact in the relationship among peak systolic tricuspid annular velocity, tricuspid annular plane systolic excursion, and right ventricular ejection fraction

OBJECTIVES

Peak systolic mitral annular velocities correlate with left ventricular ejection fraction (EF) regardless of mitral regurgitation severity. Peak systolic tricuspid annular velocity (RV-Sm) and tricuspid annular plane systolic excursion (TAPSE) are used to assess right ventricular (RV) EF (RVEF). We investigated whether tricuspid regurgitation (TR) affects the relationship among RV-Sm, TAPSE, and RVEF.

METHODS

Patients (n = 625) underwent echocardiography and Doppler tissue studies. Left ventricular EF and RVEF were estimated by Simpson's rule. Because of confounding, we excluded patients with diseases that influence mitral annular motion or left ventricular function. We finally enrolled 225 patients: 125 with mild TR, 50 with moderate TR, and 50 with severe TR. Forty study patients (20 with mild TR, 10 with moderate TR, and 10 with severe TR) received radionuclide ventriculography.

RESULTS

The RVEF estimated by Simpson's method correlated strongly to that estimated by the radionuclide method (r = 0.793, r2 = 0.629, P < .0001). With mild or moderate TR, RV-Sm correlated well to RVEF (mild TR group: r = 0.765, r2 = 0.59, P < .0001; moderate TR group: r = 0.756, r2 = 0.57, P < .0001). RV-Sm had no significant correlation to RVEF in patients with severe TR (r = 0.212, r2 = 0.05, P = .167). Over a range of TR severities, the relationship between TAPSE and RVEF showed a similar trend to that between RV-Sm and RVEF.

CONCLUSION

Severe TR has a significant impact on the relationship between RV-Sm and RVEF and between TAPSE and RVEF. TAPSE and RV-Sm in patients with severe TR show poor correlation to RVEF. When applying Doppler tissue method or TAPSE to assess RV function, severe TR is a significantly confounding factor.

An Abnormal Right Ventricular Apical Angle is Indicative of Global Right Ventricular Impairment

The presence of right ventricular (RV) dysfunction is an adverse prognostic indicator but current echocardiographic methods have some limitations. RV apical angles in systole and diastole were correlated with known parameters of RV function in patients without pulmonary hypertension (Group 1) and in patients with pulmonary hypertension (Group 2). RV apical angles were significantly smaller in both systole (22 +/- 7 degrees) and diastole (33 +/- 6 degrees) in Group 1 patients when compared to Group 2 (54 +/- 18 degrees, p < 0.0001 and 59 +/- 17 degrees, p < 0.0001, respectively). RV apical angles, both in systole and diastole, were strongly correlated with RV end-systolic area (R = 0.89, p < 0.0001) and end-diastolic area (R = 0.81, p < 0.0001), respectively. Similarly, the apical systolic and diastolic angle correlated well with decreased tricuspid annular plane systolic excursion (TAPSE, R = -0.76 and R = -0.73, p < 0.001) as well as with decreased RV fractional area change (R = -0.81 and R = -0.77, p < 0.001). Therefore, we conclude that this new measurement of RV apical angle is simple and useful to quantify RV apical structural and functional abnormalities that are well correlated with global RV impairment in patients with chronic pulmonary hypertension.