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

Evaluation of right ventricular dysfunction in patients with cardiac amyloidosis using tei index

BACKGROUND

Cardiac amyloidosis is an infiltrative disease causing predominant diastolic dysfunction and systolic dysfunction at its advanced stage. Right ventricular (RV) dysfunction is an independent predictor of poor prognosis in congestive heart failure and cardiomyopathies. However, the assessment of RV function is still technically difficult because of the complicated geometry of the RV. The recently proposed Tei index, obtained from the cardiac time interval analysis, allows noninvasive and quantitative estimation of global ventricular function without geometric evaluation. Therefore, this study was designed to assess RV function for patients with cardiac amyloidosis.

METHODS

Study patients consisted of 30 consecutive patients with biopsy specimen-proven cardiac amyloidosis and 50 control subjects. Patients were classified as having early or advanced stage of cardiac amyloidosis on the basis of mean left ventricular wall thickness < 15 mm or >/= 15 mm. Tei index, defined as the sum of isovolumetric contraction and relaxation time divided by ejection time, was obtained from tricuspid and pulmonary Doppler flow velocity.

RESULTS

RV Tei index was significantly increased for patients with cardiac amyloidosis (0.54 +/- 0.16 vs 0.28 +/- 0.05, amyloidosis vs control, P <.001). The incidences of abnormal RV isovolumetric contraction time, ejection time, isovolumetric relaxation time, and Tei index in all patients with cardiac amyloidosis were 63%, 43%, 73%, and 83%, respectively. The same incidences were 50%, 13%, 63%, and 75% in the early stage and 68%, 54%, 77%, and 86% in the advanced stage, respectively.

CONCLUSION

Patients with cardiac amyloidosis frequently have RV dysfunction even in its early stage. Tei index allows simple, noninvasive, and nongeometric estimation of RV dysfunction in patients with cardiac amyloidosis.

Validation of myocardial acceleration during isovolumic contraction as a novel noninvasive index of right ventricular contractility: comparison with ventricular pressure-volume relations in an animal model

BACKGROUND

We have demonstrated that myocardial acceleration during isovolumic contraction (IVA) is a sensitive index of left ventricular contractile function. In this study, we assessed the utility of IVA to measure right ventricular (RV) contractile function.

METHODS AND RESULTS

We examined 8 pigs by using tissue Doppler imaging of the RV free wall and simultaneous measurements of intraventricular pressure, volume, maximal elastance (e(max)), preload recruitable stroke work, and dP/dt(max) by conductance catheterization. Animals were paced in the right atrium at a rate of 130 beats per minute (bpm). IVA was compared with elastance during contractility modulation by esmolol and dobutamine and during preload reduction and afterload increase by transient balloon occlusion of the inferior vena cava and pulmonary artery, respectively. Data were also obtained during incremental atrial pacing from 110 to 210 bpm. Esmolol led to a decrease in IVA and dP/dt(max). During dobutamine infusion, IVA, dP/dt(max), preload recruitable stroke work, and e(max) all increased significantly. During preload reduction and afterload increase, IVA remained constant up to a reduction of RV volume by 54% and an RV systolic pressure increase of 58%. Pacing up to a rate of 190 bpm led to a stepwise increase in IVA and dP/dt(max), with a subsequent fall at a pacing rate of 210 bpm.

CONCLUSIONS

IVA is a measurement of RV contractile function that is unaffected by preload and afterload changes in a physiological range and is able to measure the force-frequency relation. This novel index may be ideally suited to the assessment of acute changes of RV function in clinical studies.

Echocardiographic features of the right heart in sleep-disordered breathing: the Framingham Heart Study

The effect of sleep-disordered breathing (SDB) on right heart structure and function is controversial. Studies of patients referred for evaluation of possible sleep apnea have yielded conflicting results, and the impact of SDB on the right heart has not been investigated in the general population. We examined the echocardiographic features of subjects with SDB at the Framingham Heart Study site of the Sleep Heart Health Study. Of 1,001 polysomnography subjects, 90 with SDB defined as a respiratory disturbance index (RDI) score > 90th percentile (mean RDI = 42) were compared with 90 low-RDI subjects (mean RDI = 5) matched for age, sex, and body mass index. Right heart measurements, made without knowledge of clinical status, were compared between groups. The majority of the subjects were male (74%). After multivariable adjustment, right ventricle (RV) wall thickness was significantly greater (p = 0.005) in subjects with SDB (0.78 +/- 0.02 cm) than in the low-RDI subjects (0.68 +/- 0.02 cm). Right atrial dimensions, RV dimensions, and RV systolic function were not found to be significantly different between subjects with SDB and the low-RDI subjects. We conclude that in this community-based study of SDB and right heart echocardiographic features, RV wall thickness was increased in subjects with SDB. Whether the RV hypertrophy observed in persons with SDB is associated with increased morbidity and mortality remains unknown.

Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy

OBJECTIVE

To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).

DESIGN

Prospective observational study.

SETTING

University Hospital.

SUBJECTS

15 patients with ARVC and a control group of 25 healthy subjects.

METHODS

Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.

RESULTS

Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (E(A)) velocity and an accompanying decrease in early (E(A)) to late diastolic (A(A)) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.

CONCLUSIONS

Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.

Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy

OBJECTIVE

To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).

DESIGN

Prospective observational study.

SETTING

University Hospital.

SUBJECTS

15 patients with ARVC and a control group of 25 healthy subjects.

METHODS

Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.

RESULTS

Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (EA) velocity and an accompanying decrease in early (EA) to late diastolic (AA) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.

CONCLUSIONS

Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.

Echocardiographic findings in fulminant and acute myocarditis

OBJECTIVES

We sought to use echocardiography to assess the presentation and potential for recovery of left ventricular (LV) function of patients with fulminant myocarditis compared with those with acute myocarditis.

BACKGROUND

The clinical course of patients with myocarditis remains poorly defined. We have previously proposed a classification that provides prognostic information in myocarditis patients. Fulminant myocarditis causes a distinct onset of illness and severe hemodynamic compromise, whereas acute myocarditis has an indistinct presentation, less severe hemodynamic compromise and a greater likelihood of progression to dilated cardiomyopathy.

METHODS

Echocardiography was performed at presentation and at six months to test the hypothesis that fulminant (n = 11) or acute (n = 43) myocarditis could be distinguished morphologically.

RESULTS

Patients with both fulminant (fractional shortening 19 +/- 4%) and acute myocarditis (17 +/- 7%) had LV systolic dysfunction. Patients with fulminant myocarditis had near normal LV diastolic dimensions (5.3 +/- 0.9 cm) but increased septal thickness (1.2 +/- 0.2 cm) at presentation, while those with acute myocarditis had increased diastolic dimensions (6.1 +/- 0.8 cm, p < 0.01 vs. fulminant) but normal septal thickness (1.0 +/- 0.1 cm, p = 0.01 vs. fulminant). At six months, patients with fulminant myocarditis had dramatic improvement in fractional shortening (30 +/- 8%) compared with no improvement in patients with acute myocarditis (19 +/- 7%, p < 0.01 for interaction between time and type of myocarditis).

CONCLUSIONS

Fulminant myocarditis is distinguishable from acute myocarditis by echocardiography. Patients with fulminant myocarditis exhibit a substantial improvement in ventricular function at six months compared with those with acute myocarditis. Echocardiography has value in classifying patients with myocarditis and may provide prognostic information.

Normal regional right ventricular function and its change with age: a Doppler myocardial imaging study

BACKGROUND

Doppler Myocardial Imaging (DMI) is a new technique currently being studied for the assessment of regional systolic and diastolic left ventricular (LV) function. No normal values or data on age-related changes in regional myocardial right ventricular (RV) velocities are available.

METHODS AND RESULTS

Color DMI was used in 32 healthy volunteers (aged 16-76 years) to derive regional velocities from basal, medial, and apical segments of the RV free wall in the apical 4-chamber view, and from distal segments as well as from the tricuspid annulus in the parasternal long-axis view. Both mitral annular and regional LV velocities (4-chamber, long-axis parasternal view) were also recorded and compared with corresponding RV regional velocities. The M-mode displacement of the cardiac base was measured. Corresponding RV and LV DMI data sets were compared. For longitudinal function, RV free wall systolic velocities were consistently higher than velocities recorded in corresponding LV segments (analysis of variance, P <.05). Older subjects (40-76 years; 13 men, 2 women) had lower RV long-axis regional velocities than younger subjects (16-39 years; 15 men, 2 women), but had higher short-axis RV systolic velocities. For diastolic velocities, a negative correlation between age and the ratio of regional early diastolic to late diastolic velocity was shown for all RV free wall segments (eg, basal segment: r = -0.63, P <.0001).

CONCLUSIONS

The right ventricle has higher long-axis regional velocities, a greater excursion of its lateral atrioventricular valve ring, and reduced circumferential shortening velocities compared with the left ventricle. Right ventricular longitudinal shortening is dominant over short-axis function in healthy young subjects. Normal age-related changes of diastolic velocities for each segment of the normal RV free wall have been defined.

C-reactive protein as a prognostic marker in lymphocytic myocarditis

The prognosis of patients with lymphocytic myocarditis (LM) is poor with the combined endpoint of death or transplant in the Myocarditis Treatment trial being 56% at 5 years. Physicians often have difficulty determining the prognosis in an individual patient. Patients with LM may have ongoing myocardial inflammation. We evaluated the ability of a serum marker of inflammation to predict prognosis in patients with LM. Serum concentrations of C-reactive protein (CRP) were measured in patients with LM. Thiry-one patients with clinical and histologic evidence of LM were evaluated. Patients with coronary artery disease, and idiopathic dilated and secondary cardiomyopathies were excluded. Overall mortality and morbidity from congestive heart failure was assessed at 28 days. The mean plasma CRP concentrations in the five patients who died within the 28-day follow-up period were significantly higher than in those patients who survived (17.4 +/- 5.6 vs 5.9 +/- 3.3 mg/ml, p < 0.05). The CRP concentration was positively correlated with plasma levels of lactic dehydrogenase and the New York Heart Association functional class. Routine measurement of CRP may be a useful tool for determining the prognosis in patients with LM.

Prognostic significance of echocardiographically estimated right ventricular shortening in advanced heart failure

Little is known about the association of echocardiographic estimates of right ventricular (RV) function with survival, in relation to hemodynamic and exercise-derived predictors of outcome in congestive heart failure. We prospectively studied 40 patients (age 55+/-10 years, in New York Heart Association functional class III [70%] and IV [30%]), with left ventricular (LV) ejection fraction <30%. At enrollment, all patients underwent echocardiographic evaluation of LV dimensions and function. RV shortening was measured as the difference of the end-diastolic distance - the end-systolic distance between the tricuspid annulus and the RV apex. Thirty-five patients (88%) were able to perform a maximal symptom-limited exercise test. Peak oxygen consumption (peak VO2) and percent peak age- and gender-adjusted predicted oxygen consumption (%peak VO2) were calculated. Of 40 patients, 10 died during a mean follow-up period of 14+/-10 months. On univariate analysis, nonsurvivors had lower RV shortening (p=0.0001), higher pulmonary artery wedge pressure (p=0.009), higher pulmonary vascular resistance (p=0.02), and lower mean aortic pressure (p=0.05). Cox proportional-hazards model revealed that the only independent associate of survival was RV shortening (p=0.0005), with a trend toward significance for mean aortic pressure (p=0.08). The best cutoff point of RV shortening identified by the receiver-operating curve was 1.25 cm. This value had a sensitivity of 90%, specificity of 80%, and overall predictive accuracy of 83% to distinguish survivors from nonsurvivors. In patients with advanced heart failure, preserved RV function as indicated by an echocardiographically derived RV shortening > 1.25 cm is a strong predictor of survival.

Acutely severe myocarditis successfully treated by percutaneous cardiopulmonary support applied by a newly developed heparin-binding oxygenator and circuits

The feasibility of using the heparin-bound percutaneous cardiopulmonary support system (PCPS) for prolonged extracorporeal circulation in patients with acute severe myocarditis is demonstrated. The case histories of 2 patients with cardiogenic shock caused by acute myocarditis are presented; both were successfully treated with long-term PCPS using a newly developed heparin-binding oxygenator and circuits without changing the oxygenator. The courses of both patients remain uneventful more than 12 months after discharge. We also discuss the clinical aspects of using heparin-bound PCPS in patients with acute severe myocarditis.

Right ventricular dilation in primary amyloidosis: an independent predictor of survival

This study was designed to characterize the geometry and function of the right ventricle and its prognostic significance in patients with primary (AL) cardiac amyloidosis. AL amyloidosis is an infiltrative systemic disease that can result in thickening of heart structures and rapidly progressive congestive heart failure due to restrictive ventricular physiology and eventual systolic dysfunction. Thirty-seven patients with AL amyloid heart involvement and 20 normal control subjects were evaluated using 2-dimensional and Doppler echocardiography. Based on the ratio of left-to-right end-diastolic ventricular chamber areas, patients were classified into 2 groups: 25 patients with disproportionate right ventricular (RV) dilation (left ventricular to RV ratio < or = 2) and 12 with a ventricular area ratio > 2. Patients with a relatively dilated right ventricle (ratio < or = 2) had a shorter median survival (4 months) compared with patients with an area ratio > 2 (10 months, p <0.003). Of multiple clinical, echocardiographic, and Doppler features entered into a multifactorial model, a ventricular area ratio < or = 2 remained the only independent predictor of survival. Patients with AL amyloid heart disease represent a heterogeneous population with regard to both prognosis and the relative degree of right to left ventricular dilation. RV dilation in patients with amyloid heart disease appears to be associated with more severe involvement and is associated with a very poor prognosis with a median survival of only 4 months.

Inflammatory myocardial diseases and cardiomyopathies

Inflammatory myocardial disease has been associated with a variety of infectious and noninfectious etiologies. It is associated with the development of dilated cardiomyopathy in some patients. Given its imprecise diagnosis, varied clinical presentation and undefined natural history, it is quite difficult to make broad generalizations regarding its evaluation and treatment. It is hoped continued application of new molecular biological and other techniques will shed further light on the pathophysiologic mechanisms of myocarditis in humans, thus pointing to therapeutic interventions.

Echocardiographic Assessment of Right Ventricular Volume and Function

Echocardiographic evaluation of right ventricular volume and function has become a subject of growing interest with the increasing awareness of the important role of the right ventricle in the entire circulation. However, the anatomically complex and load-dependent shaped right ventricle shape is difficult to describe by a simple geometric figure and its volume and function are, therefore, difficult to assess in a simple manner. A number of echocardiographic methods for evaluating right ventricular volume and function have emerged; to date, however, their quantification remains a clinical challenge. The major goal is to develop a reproducible method that will allow for quantitative comparisons between patients or serially within a given patient. This discussion examines the available methods with specific attention to their reliability and limitations. Visual inspection or measurement of single plane indices is limited by their lack of standardization and failure to describe the entire right ventricle. Simpson's rule requires computer calculations and assumes an elliptic symmetry present in the left, but not the right ventricle. Application of the area-length method to the subcostal outflow tract and apical four-chamber views is a particularly practical current approach. Three-dimensional echo reconstruction, which eliminates the need for geometric assumptions and individual standardized views, although only in its infancy, promises to be the most accurate method for right ventricular volume calculation and in the future should emerge as the standard for research and many clinical applications.