Abnormal ventricular long-axis function in systemic sclerosis

Sudden cardiac death, arrhythmias and abnormal electrocardiography in systemic sclerosis: A systematic review and meta-analysis

OBJECTIVE

To calculate the frequency of sudden cardiac death(SCD), arrhythmia and conduction defects in SSc.

METHODS

MEDLINE/EMBASE were searched to January 2023. English-language studies reporting the incidence/frequency of SCD, arrhythmia and electrocardiography(ECG) abnormalities in SSc were included. Odds ratios(OR), estimations of annual incidence or pooled frequencies were calculated.

RESULTS

Seventy-nine studies(n = 13,609 participants with SSc) were included in the meta-analysis. Methodology and outcomes were heterogeneous. Ten studies included cohorts with known/suspected SSc-associated heart involvement(SHI), generally defined as clinically-manifest cardiac disease/abnormal cardiac investigations. The incidence of SCD in SHI was estimated to be 3.3% annually(n = 4 studies, 301PY follow-up). On ambulatory ECG, 18% of SHI cohorts had non-sustained ventricular tachycardia(NSVT; n = 4, 95%CI3.2-39.3%), 70% frequent premature ventricular complexes (PVCs; n = 1, 95%CI34.8-93.3%), and 8% atrial fibrillation (AF; n = 1, 95%CI4.2-13.6%). Nineteen studies included participants without SHI, defined as normal cardiac investigations/absence of cardiac disease. The estimated incidence of SCD was approximately 2.9% annually (n = 1, 67.5PY). Compared to healthy controls, individuals without SHI demonstrated NSVT 13.3-times more frequently (n = 2, 95%CI2-102), and paroxysmal supraventricular tachycardia 7-times more frequently (n = 4, 95%CI3-15). Other ambulatory ECG abnormalities included NSVT in 9% (n = 7, 95%CI6-14%), >1000 PVCs/24 h in 6% (n = 2, 95%CI1-13%), and AF in 7% (n = 5, 0-21%). Fifty studies included general SSc cohorts unselected for cardiac disease. The incidence of SCD was estimated to be 2.0% annually(n = 4 studies, 1646PY). Unselected SSc cohorts were 10.5-times more likely to demonstrate frequent PVCs (n = 2, 95%CI 2-59) and 2.5-times more likely to have an abnormal electrocardiography (n = 2, 95%CI1-4).

CONCLUSIONS

The incidence of SCD in SSc is estimated to be 1.0-3.3% annually, at least 10-fold higher than general population estimates. Arrhythmias including NSVT and frequent PVCs appear common, including amongst those without known/suspected SHI.

Arrhythmias and Conduction Disturbances in Patients with Systemic Sclerosis—A Systematic Literature Review

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and internal organ fibrosis and microvascular impairment, which can affect major organs, including the heart. Arrhythmias are responsible for approximately 6% of deaths in patients with SSc, and mainly occur due to myocardial fibrosis, which causes electrical inhomogeneity. The aim of this study was to determine the frequency of arrhythmias and conduction disturbances in SSc cohorts, and to identify the characteristics and risk factors associated with the occurrence of dysrhythmias in patients with SSc. A systematic literature review using PubMed, Embase, Web of Science and Scopus databases was performed. Full-text articles in English with arrhythmias as the main topic published until 21 April 2022 were included. Most prevalent arrhythmias were premature supraventricular and ventricular contractions, while the most frequent conduction disturbance was represented by right bundle branch block (RBBB). Elevated concentrations of N-terminal prohormones of brain natriuretic peptides (NT-pro BNP) were associated with numerous types of atrial and ventricular arrhythmias, and with the occurrence of RBBB. A lower value of the turbulence slope (TS) emerged as an independent predictor for ventricular arrhythmias. In conclusion, dysrhythmias are frequent in SSc cohorts. Paraclinical and laboratory parameters are useful instruments that could lead to early diagnosis in the course of the disease.

Determinants of left ventricular structure, filling and long axis function in systemic sclerosis

Background

Abnormalities of left ventricular (LV) structure, filling and long-axis function have all been reported in subjects with systemic sclerosis (SSc) and a normal LV ejection fraction (EF), but previous study findings have not been consistent. The aim of this study was to identify factors which could have confounded the analyses in previous studies of SSc, and in particular to consider the variables of body surface area (BSA), sex, age, heart rate, blood pressure (BP), disease duration (DD), disease type (limited versus diffuse) and interstitial lung disease (ILD).

Methods

Echocardiography was performed on 100 subjects with SSc (79 women; age 56±15 years) with a LVEF ≥50% and free of pulmonary arterial hypertension, coronary artery disease, more than mild valvular heart disease and atrial fibrillation. Measurements were performed of the LV end-diastolic dimension (LVEDD) and septal wall thickness (SWT), the transmitral Doppler E, A and deceleration time (DT), and the peak systolic (s’) and early diastolic (e’) LV long-axis velocities. Multivariate analyses were performed to investigate correlations of the above LV variables with BSA, sex, age, heart rate, BP, DD, disease type, and the presence of ILD.

Results

DD varied between 0.1 and 41.2 years, 25% had diffuse and 75% had limited disease, and 37% had ILD. SWT and LVEDD were positively correlated with BSA, SWT was also positively correlated with age and larger in males, and LVEDD was larger in diffuse disease. Age was positively correlated with A and DT, and inversely correlated with E and E/A, and heart rate was inversely correlated with E and E/A. None of E, A, E/A, or DT were independently associated with DD or disease type. Septal and lateral LV wall s’ and e’ were all inversely correlated with age, and there was a small independent contribution to the prediction of lateral s’ from DD, but no association of either s’ or e’ with disease type. The presence of ILD was not a predictor of any of the LV variables.

Conclusion

In SSc there are associations of sex, body size, age and disease type with LV structural variables, of age and heart rate with E/A, and of age with both systolic and early diastolic LV long-axis velocities. Appropriate adjustment for these variables could help to resolve current uncertainties regarding SSc effects on the left ventricle.

Impact of age and sex on normal left heart structure and function

BACKGROUND

Accurate age- and sex-related normal reference values of ventricular structure and function are important to determine the level of dysfunction in patients. The aim of this study therefore was to document normal age range sex-related measurements of LV structural and functional measurements to serve such purpose.

METHODS

We evaluated left ventricular structure and function in 293 healthy subjects between 20 and 90 years with equally distributed gender. Doppler echocardiography was used including measure of both systolic and diastolic functions.

RESULTS

Due to systolic LV function, only long axis function correlated with age (r = 0·55, P<0·01) and the correlation was stronger in females. Concerning diastolic function, there was a strong age correlation in all parameters used (r = 0·40-0·74, P<0·001). Due to LV structural changes over age, females showed a larger reduction in end-diastolic volumes, but no or trivial difference in wall thickness after the age of 60 years.

CONCLUSION

Age is associated with significant normal changes in left ventricular structure and function, which should be considered when deciding on normality. These changes are related to systemic arterial changes as well as body stature, thus reflecting overall body ageing process. Furthermore, normal cardiac ageing in females might partly explain the higher prevalence of heart failure with preserved ejection in females.

Right ventricular thickness as predictor of global myocardial performance in systemic sclerosis: A Doppler tissue imaging study

BACKGROUND

Cardiopulmonary involvement in systemic sclerosis (SSc) is a poor prognostic factor, due to pulmonary hypertension and right ventricular dysfunction. We assessed the echocardiographic parameters of right ventricular (RV) function in SSc and correlated echocardiographic findings to clinical features of the disease.

METHODS

Thirty patients with SSc (cases) and 30 healthy, age-matched subjects (controls) were studied. Echocardiography, including tissue Doppler imaging, was used to evaluate cardiac function.

RESULTS

Pulmonary hypertension could be documented in only 5 cases by Doppler echo, using Bernoulli principle. RV diastolic function was significantly deranged in cases. RV systolic function and left ventricle (LV) diastolic function were also significantly deranged in the cases. RV thickness was increased in patients with SSc. There were no significant differences in the echocardiographic variables between diffuse and limited subtypes of SSc. Myocardial performance index (MPI) of both ventricles were increased in cases. We could demonstrate RV thickness as the single most important predictor of MPI of both ventricles with sensitivity of 82% and specificity of 72% for RV-MPI and 63% for LV-MPI. Diastolic function was not found to be affected by disease duration or Rodnan skin score.

CONCLUSION

Patients with SSc exhibit abnormal RV and LV diastolic functions as well as abnormal RV systolic function. RV wall thickness was found to be simple and the single best predictor of global myocardial performance. RV dysfunction may be a response to intermittent pulmonary arterial hypertension, lung parenchymal involvement, or secondary to LV diastolic dysfunction in SSc.

The normal impact of age and gender on right heart structure and function

BACKGROUND

As the proportion of elderly population increases rapidly, it might be difficult to differentiate physiological changes in cardiac function due to age from the pathophysiological ones. In addition, cardiac function variations with gender are well established. The right ventricular (RV) plays an important role in the overall cardiac function, but reference values varying with age and gender are lacking.

MATERIAL AND METHODS

We studied 255 healthy individuals from a general population register, mean age of 58 ± 19 (range 22-89) years, 125 were females. We used 2D and M-mode echocardiography to measure RV inflow tract (RVIT) and RV outflow tract (RVOT) dimensions and fractional shortening (fs). Spectral Doppler echocardiography was also used.

RESULTS

We found a modest decrease in RVIT dimensions (P < 0.05), but increase in RVOT dimensions with advancing age (P < 0.05). A small decrease in RVOT fs with age was also found (P < 0.05). Estimated pulmonary pressures and pulmonary vascular resistance increased (P < 0.001) as did RVOT wall thickness (P < 0.001), but RV diastolic function was not altered (P < 0.001) with age. Despite correction for the BSA, males showed larger RVIT dimensions (P < 0.001 for both), but RVOT end-diastolic dimension was larger in females (P < 0.05). RVIT and RVOT fractional shortening were increased in females (P < 0.01 for both).

CONCLUSION

In a cohort of normal individuals, age has significant impact on RV structure and function, inlet area falls and outflow tract dimensions increase and fractional shortening also increase in females. In addition, RVOT wall thickness significantly increases and Doppler markers of pulmonary vascular resistance show a consistent rise. The age-related changes should carefully be considered when commenting on normality and when using absolute values.

Pattern and distribution of myocardial fibrosis in systemic sclerosis: a delayed enhanced magnetic resonance imaging study

OBJECTIVE

To assess the prevalence and pattern of myocardial fibrosis as detected by delayed enhanced magnetic resonance imaging (DE-MRI) in patients with systemic sclerosis (SSc), and to evaluate a possible association between myocardial fibrosis and cardiac arrhythmias.

METHODS

Forty-one patients with SSc underwent 24-hour Holter monitoring, Doppler echocardiography, and DE-MRI following gadolinium administration.

RESULTS

Technically acceptable DE-MRIs were obtained in 36 patients with SSc. Enhancement on DE-MRI, consistent with myocardial fibrosis, was observed in 24 of these patients (66%), and it was invariably midwall with a linear pattern, mostly involving basal and midcavity segments of the left ventricle. The volume of enhancement (total volume percentage index [TVPI]) did not differ between patients with diffuse SSc and those with limited SSc (mean +/- SD 1.46 +/- 1.73% versus 1.44 +/- 1.77%; P = 0.98). Patients with a long duration (> or = 15 years) of Raynaud's phenomenon had a greater number of enhancing segments (mean +/- SD 6.55 +/- 4.93 versus 2.96 +/- 3.46; P = 0.017) and a greater TVPI (mean +/- SD 2.44 +/- 1.97% versus 1.02 +/- 1.43%; P = 0.02) than those with a duration of Raynaud's phenomenon <15 years. Nineteen patients with SSc (53%) had abnormal Holter study results. Compared with patients with normal Holter study results, those with abnormal results had a greater number of enhancing segments (mean +/- SD 5.4 +/- 4.8 versus 2.5 +/- 2.9; P < 0.05) and a greater TVPI (mean +/- SD 2.1 +/- 1.9% versus 0.8 +/- 1.2%; P < 0.05).

CONCLUSION

DE-MRI can identify myocardial fibrosis in a significant percentage of patients with SSc and may be a useful noninvasive tool for determining cardiac involvement.

Right ventricular myocardial isovolumic relaxation time and pulmonary pressure. Pulsed Doppler tissue imaging in resurrection of Burstin's nomogram

AIMS

Non-invasive assessment of pulmonary artery systolic pressure (PASP) has several limitations. As previously described by Burstin, the right ventricular (RV) isovolumic relaxation time (IVRt) is sensitive to changes in PASP. We therefore compared RV myocardial IVRt, derived by Doppler tissue imaging (DTI), with simultaneously measured invasive PASP.

METHODS AND RESULTS

Twenty-six consecutive patients (18 males, mean age 52 +/- 12 years, range 23-75) underwent a simultaneous Doppler echocardiography, including DTI, and cardiac catheterization examination for measurement of PASP and right atrial mean pressures. IVRt was measured using the myocardial velocities by pulsed DTI at both basal and mid cavity segments of the RV free wall. As diastolic time intervals are influenced by heart rate IVRt was corrected for heart rate (IVRt/RR%). A significant correlation was found between PASP and regional IVRt/RR% at both the basal (r = 0.42, P<0.05) and mid cavity segment (r = 0.71, P<0.001). Furthermore, when only patients with normal right atrial pressures (<7 mmHg) were taken into account, the correlation coefficient improved at both basal and mid cavity segments (r = 0.74, P<0.05 and r = 0.83, P<0.01).

CONCLUSION

Pulsed Doppler-derived IVRt correlates well with PASP. The use of pulsed DTI for measurement of IVRt is simple, reproducible and easy to obtain. We propose this method as an additional non-invasive tool in the assessment of PASP.

Disturbed Right Ventricular Diastolic Function in Patients With Systemic Sclerosis

BACKGROUND

Cardiopulmonary involvement in patients with systemic sclerosis (SSc) carries a poor prognosis, mainly due to pulmonary hypertension and right-heart failure. To date, right ventricular (RV) involvement has not been studied in detail. We therefore assessed RV function in patients with SSc and related the findings to the clinical features of the disease.

METHOD

Twenty-six consecutive patients (21 women) with SSc (mean age, 56 +/- 15 years [+/- SD]) and 25 healthy, age-matched control subjects (21 women) were studied. Doppler echocardiography including Doppler tissue imaging was used to evaluate cardiac function. Pulmonary function was also studied.

RESULTS

Compared with control subjects, RV free wall thickness (5.8 +/- 1.7 mm vs 3.7 +/- 1.1 mm, p < 0.001) and right atrial (RA) systolic area (15.9 +/- 3.7 cm2 vs 13.0 +/- 2.3 cm2, p < 0.01) were increased in patients with SSc, while the global early diastolic/atrial component velocity ratio was reduced (1.2 +/- 0.4 vs 1.7 +/- 0.6, p < 0.01). The global isovolumic relaxation time (IVRT) [64 +/- 23 ms vs 39 +/- 13 ms, p < 0.001] and regional IVRT (83 +/- 40 ms vs 46 +/- 24 ms, p < 0.001) were prolonged in patients vs control subjects, whereas the RV global filling time was reduced (454 +/- 122 ms vs 548 +/- 104 ms, p < 0.01). RV systolic function and pulmonary pressures at rest were similar in the two groups, but the pulmonary artery acceleration time was reduced (119 +/- 34 ms vs 141 +/- 29 ms, p < 0.05) in patients compared to control subjects. Left ventricular function did not differ between the two groups.

CONCLUSION

Patients with SSc exhibit altered RV diastolic function together with an increase in RV wall thickness and RA area. These findings appear to be early markers of RV disturbance, probably in response to intermittent pulmonary arterial hypertension.

Three-dimensional assessment of two-dimensional technique for evaluation of right ventricular function by tricuspid annulus motion

BACKGROUND

Measurement of tricuspid annulus motion (TAM) is an easy way to estimate right ventricular ejection fraction (RVEF). However the accuracy of two-dimensional (2-D) methods for analyzing the three-dimensional (3-D) structure of the tricuspid annulus has not been evaluated.

OBJECTIVE

This study evaluated the accuracy with which 2-D measurements of TAM reflect RVEF using 3-D reconstructions of the heart at end diastole (ED) and end systole (ES).

METHODS

2-D echocardiographic studies were performed on 12 subjects and used to reconstruct the RV and tricuspid annulus in 3-D at ED and ES. Measurements of TAM from medial and lateral positions on the annulus were selected from the standard echocardiographic apical four-chamber view. The minimum and maximum possible TAM values, RV volumes, and movement of the apex of the heart along the trajectory of TAM were calculated from the 3-D reconstructions.

RESULTS

TAM correlated highly with RVEF (r > or = 0.90). Values found by 2-D and 3-D techniques were not significantly different. Correcting TAM for apex motion did not improve correlation. Summation of medial and lateral TAM data increased correlation values slightly relative to lateral TAM alone. Regional aberrant contractility degraded the predictive value of TAM.

CONCLUSION

Estimation of RVEF from 2-D echo measurement of TAM is accurate, especially when medial and lateral TAM are summed, except in patients with severe apical RV dysfunction.

Correlates of subclinical left ventricular dysfunction in ESRD

BACKGROUND

Abnormalities of the left ventricle are common in patients with end-stage renal disease (ESRD) both before and after the start of renal replacement therapy. The purpose of this study is to identify possible causes of subclinical left ventricular (LV) dysfunction in patients with ESRD. In particular, we sought to determine whether the presence of ESRD was itself associated with dysfunction independent of LV hypertrophy and coronary artery disease.

METHODS

Assessment of cardiovascular risk factors and dialysis adequacy was completed in 145 unselected patients with ESRD who were recruited from the renal dialysis unit and compared with age- and sex-matched controls. Among the 68 patients with ESRD who had undergone a dobutamine stress echocardiogram with normal findings, regional cardiac function was quantified by myocardial Doppler velocity, LV volumes and mass were measured using three-dimensional echocardiography, and vascular function was assessed using brachial artery reactivity (BAR).

RESULTS

LV diastolic velocity was impaired in patients with ESRD, but there was no significant difference in systolic velocity compared with control patients of similar age. Age, diabetes mellitus, hypertension, and LV mass were independent predictors of diastolic velocity (model R2 = 0.45; P < 0.001), whereas age and risk factor number were predictors of systolic velocity (model R2 = 0.19; P = 0.002). Increasing risk factor number had no significant relationship with LV mass or volume. There was no detected association between BAR and incremental risk factors (P = 0.51).

CONCLUSION

Subclinical LV dysfunction occurs in patients with ESRD, but is evidenced as abnormal myocardial diastolic, rather than systolic, function. Correlates of abnormal function are age, diabetes mellitus, hypertension, and LV mass, rather than ESRD alone, dialysis adequacy, or abnormal endothelial function.

Right and left ventricular long-axis function in the fetus using angular M-mode

OBJECTIVE

Long-axis function is determined by the longitudinally oriented myocardial fibers. Postnatally, conventional M-mode is used to assess tricuspid and mitral valve ring movements in relation to the cardiac apex. During fetal life, this is precluded by variable fetal position. We assessed the feasibility of determining right and left ventricular long-axis function in the fetus.

METHODS

A prospective, pilot study. The four-chamber view obtained during routine fetal echocardiography was recorded in a cineloop to which B-mode guided M-mode echocardiography was applied using angular M-mode. This allowed retrospective and correct placement of the cursor line from cardiac apex to tricuspid or mitral valve rings. M-mode tracings of the valve ring movements in relation to the apex were derived from the originally stored loop. Data from 18 fetuses (17-29 weeks of gestation) were available for analysis. Total excursion of the valve rings was measured offline. A second cursor line was simultaneously placed in the left ventricular outflow tract during color flow mapping for timing purposes (n = 6).

RESULTS

Right and left ventricular long-axis recordings were obtained in 18 and 14 cases, respectively. Total right ventricular excursion was 5.2 mm (SD, 0.9 mm) (range, 3.9-7.2 mm). Total left ventricular free wall excursion was 4.5 mm (SD, 1.1 mm) (range, 3.0-6.8 mm). For paired data, the mean of differences (right ventricle-left ventricle) was 0.8 mm (95% confidence interval 0.5-1.2). The valve rings moved towards the apex during systole (shortening) and away from it during diastole (lengthening). Peak downward movement coincided with cessation of aortic flow and diastolic lengthening with flow through the atrioventricular valves.

CONCLUSION

Long-axis function in the fetus is feasible if M-mode angle correction is used. There was no clinically significant difference between tricuspid and mitral valve excursions. The pattern of atrioventricular valve movement is coordinate and similar to that of adults. Long-axis function offers a new avenue to study systolic and diastolic function in the fetus.

Disturbed atrioventricular electromechanical function long after Mustard operation for transposition of great arteries: a potential contributing factor to atrial flutter

OBJECTIVE

The objectives were to study atrial and ventricular electromechanical function in patients long after Mustard repair for transposition of great arteries and to identify possible causes and physiologic disturbances in those with recurrent atrial flutter.

METHODS

Electromechanical atrial and ventricular function was assessed in 22 patients (11 women) aged 27 +/- 5 years, 10 to 29 (mean 24) years after initial Mustard operation with electrocardiography and echocardiography. The study subjects involved 12 patients with documented atrial flutter and the remaining 10 without history of atrial arrhythmia served as controls. All patients were studied while in sinus rhythm.

RESULTS

There was no difference in age, gender, or age at original Mustard surgery between the 2 patient groups. The P wave and QRS duration were significantly broader in patients compared with controls (128 +/- 14 ms vs 100 +/- 10 ms, P <.05 and 120 +/- 20 ms vs 93 +/- 6 ms, P <.01). Right ventricular end diastolic dimension was not different, whereas left ventricular fraction shortening was less (20% +/- 10% vs 35% +/- 12%, P <.01) in the patient group. Left and septal total ventricular long axes amplitude were significantly lower in patients compared with controls (1.4 +/- 0.4 cm vs 1.7 +/- 0.3 cm, P <.05 and 0.6 +/- 0.2 cm vs 1.0 +/- 0.3 cm, P <.01). Right-sided total long axis excursion was equally reduced in the 2 groups (1.0 +/- 0.3 cm). Septal and right-sided but not left-sided "a" wave was smaller in the patients (1.2 +/- 1 mm vs 3 +/- 1.2 mm, P <.001 and 1 +/- 1.3 mm vs 3 +/- 0.9 mm, P <.01). Right atrial electromechanical delay was significantly longer in patients with respect to controls (110 +/- 14 ms vs 84 +/- 25 ms, P <.001), but on the left there was no difference. The P wave duration correlated closely with right atrial electromechanical delay, r = 0.79, P <.003. Significant tricuspid regurgitation was found in 9 of 12 patients but none of the controls.

CONCLUSION

Right ventricular dysfunction is present long after Mustard operation for transposition of great arteries whether flutter occurs. However, in patients with history of atrial flutter, evidence of left ventricular dysfunction, significant tricuspid regurgitation, impaired right atrial electrical and mechanical function, and reversed onset of atrial systole is also present. The consistent association of the disturbed atrial and ventricular electromechanical behavior suggests a multifactorial etiology for atrial arrhythmia.

Right ventricular dysfunction in adult severe cystic fibrosis

STUDY OBJECTIVES

This study sought to assess the extent of impairment of cardiac function in adult patients with end-stage cystic fibrosis (CF) and to examine the relationship between cardiovascular abnormalities and the degree of hypoxemia and hypercapnia.

DESIGN AND SETTING

A retrospective study in a tertiary cardiac and CF center.

PARTICIPANTS AND INTERVENTIONS

A total of 103 adult patients with end-stage CF awaiting lung or heart and lung transplantation (mean age [+/- SD], 26+/-7 years; 54 men) underwent Doppler echocardiography and arterial blood gas analysis (mean PaO(2), 54+/-10 mm Hg; mean PaCO(2), 47+/-8 mm Hg). The findings were compared to those of 17 healthy control subjects (mean age, 24+/-7 years; 13 men) who had no history of cardiac or pulmonary disease.

MEASUREMENTS AND RESULTS

All patients were in sinus rhythm with a mean tachycardia of 112+/-18 beats/min (control subjects, 76+/-16; p<0.0001) and had a cardiac output of 5.3 L/min (control subjects, 4.3 L/min; p<0.04). In the patient group, the left ventricular (LV) dimensions, systolic and diastolic function, and wall thickness were all within normal limits. The mean amplitude of long-axis excursion in patients was normal at the LV site, but that of the right ventricular (RV) free wall was significantly reduced as compared with control subjects (1.6+/-0.4 vs. 2.2+/-0.4 cm, respectively; p<0.001), which was found to correlate with the degree of hypoxemia (r = 0.63; p<0.02) and hypercapnia (r = -0.68; p<0.01). RV diastolic function, which was represented by the relative isovolumic relaxation time to cardiac cycle length, was longer in patients than in control subjects (8.7+/-4.8% vs. 5.0+/-3.0%, respectively; p<0.03). The pulmonary flow acceleration time (90+/-22 vs 121+/-34 ms, respectively; p<0.01) and the systolic stroke distance (7.0+/-2.2 vs. 10.5+/-1.9 cm/s(2); p<0.001) were both lower than normal.

CONCLUSIONS

This study confirms the presence of significant RV systolic and diastolic dysfunction in the setting of consistent tachycardia and increased cardiac output in adult CF patients with severe disease. No specific LV abnormalities were detected in these patients.

Patients with pulmonary fibrosis: cardiac function assessed with MR imaging

PURPOSE

To detect abnormalities in cardiac function by using magnetic resonance (MR) imaging in patients with mild to moderate pulmonary fibrosis and to evaluate the relationship between pulmonary function and cardiac function.

MATERIALS AND METHODS

Sixteen patients were compared with 16 sex- and age-matched healthy control subjects. Systolic function was assessed by using multisection multiphase cine MR imaging. Diastolic function was assessed with flow-sensitive MR imaging across the mitral and tricuspid valves. MR imaging results were compared with the severity of impairment in pulmonary function.

RESULTS

Biventricular systolic function and left ventricular diastolic function were normal in patients, but right ventricular diastolic function was significantly impaired versus that of control subjects, with a ratio of peak flow during early diastolic (E) filling to peak flow during atrial contraction (A) of 0.85 +/- 0.40 versus 1.28 +/- 0.50 (P =.035). Biventricular E/A ratios were strongly correlated to age in patients and control subjects. The right ventricular E/A ratio in patients corresponded with values that are normally expected in people 20 years older. Diastolic left and right ventricular functions were significantly correlated with each other. There was no relationship between pulmonary function and cardiac function.

CONCLUSION

Impairment of right ventricular diastolic function was found by using MR imaging in patients with mild to moderate pulmonary fibrosis, whereas left ventricular diastolic function and biventricular systolic function were preserved.

Different response of patients with idiopathic and ischaemic dilated cardiomyopathy to exercise training

We looked at the benefits and complications of a home-based exercise programme in patients with ischaemic and idiopathic dilated cardiomyopathy. Twenty-four patients with left ventricular end-diastolic dimension >6.5 cm and fractional shortening <25% entered a cross-over trial of 8 weeks training versus 8 weeks rest. Echocardiography, electrocardiogram and cardiopulmonary exercise testing were performed at baseline, after training and after detraining. Training resulted in a higher peak oxygen consumption (26.5 versus 21.3 ml/kg/min, P=0.004), a higher peak heart rate (161 versus 152 bpm, P=0.02) and improved well-being. Patients with idiopathic dilated cardiomyopathy showed a significant increase in exercise time (879 versus 828 s, P=0.03) and peak oxygen consumption (31.3 versus 24.3 ml/kg/min, P=0.02) and a decrease in left ventricular end-diastolic dimension (6.4 versus 6.9 cm, P=0.01) and end-systolic dimension (5.3 versus 5.8 cm, P=0.04) in contrast to those with coronary artery disease, who developed a reduction in septal excursion and shortening rate following training. Complications of training were more common in those patients with ischaemic cardiomyopathy, greater left ventricular dimensions, poorer exercise tolerance and greater ventilation drive at baseline, and included fluid retention and exercise-induced ventricular tachycardia. We found that this group of patients with a dilated, poorly functioning left ventricle can safely derive benefit from a home-based exercise programme, particularly those of idiopathic origin, but they should be closely monitored for the development of complications.

Right ventricular long axis function in adults and children with Ebstein's malformation

OBJECTIVES

To assess right ventricular function in adults and children with Ebstein's anomaly.

DESIGN

Prospective study.

SETTING

Tertiary referral centre.

SUBJECTS

Fifteen patients (8 adults and 7 children) with Ebstein's anomaly and 14 healthy controls.

INTERVENTIONS

Transthoracic echocardiography was performed in all. Right ventricular function was assessed from long axis M-mode recordings of the right atrio-ventricular free wall. Total systolic excursion as well as peak shortening and lenghtening rates of the right ventricle were measured.

RESULTS

Children and adult patients with Ebstein's anomaly differed in terms of age at diagnosis, the adult group having been diagnosed later 19.8+/-15.8 vs. 5.9+/-6.2 years, P<0.05. Measures of right ventricular long axis function in children with Ebstein's anomaly showed a significantly reduced systolic excursion 1.4+/-0.4 vs. 2.4+/-0.53 cm, P<0.05 and peak lenghtening rate; early 8.04+/-4.3 vs. 11.8+/-2.4 cm/s and late 6.14+/-3.6 vs. 10.6+/-4.3 cm/s, P=0.05 compared to controls. In contrast, measurements of right ventricular long axis function in adults with Ebstein's anomaly showed no significant difference when compared to the control group. Transtricuspid Doppler flow velocities were not different between patient's groups and corresponding controls.

CONCLUSION

The right ventricle assessed by this simple, non-invasive technique reveals a significantly reduced systolic and diastolic function in children with Ebstein's malformation compared to controls but a 'normal' right ventricular function comparable to controls in adult patients. Significant right ventricular dysfunction in children with Ebstein's anomaly could account for their earlier presentation. Long term follow up of the right ventricular abnormalities is needed in such children to discover more about the natural history of the disease.

Echo derived variables predicting exercise tolerance in patients with dilated and poorly functioning left ventricle

OBJECTIVE

To determine whether resting echo derived measurements predict exercise tolerance and its interrelation with heart rate response and ventilation drive in patients with systolic left ventricular disease.

DESIGN

Prospective echocardiographic examination followed by cardiopulmonary exercise testing.

SETTING

A tertiary referral centre for cardiac diseases.

SUBJECTS

21 patients (11 with coronary artery disease, 10 with idiopathic dilated cardiomyopathy) with end diastolic dimension > 6.4 cm, shortening fraction < 25%, and in sinus rhythm. There were 11 age matched normal controls.

RESULTS

In the patients, peak oxygen consumption (mVo2) correlated with right ventricular long axis excursion (r = 0.62); 65% of the variance in mVo2 was predictable using a multivariate model with right ventricular long axis excursion and peak lengthening rate, and peak mitral atrial filling velocity as independent variables. Aetiology was not an independent predictor, although the right ventricular long axis excursion (mean (SD)) was greater in patients with idiopathic dilated cardiomyopathy than in those with coronary artery disease (2.4 (0.5) cm v 1.6 (0.5) cm, p < 0.001). Peak heart rate correlated with duration of mitral regurgitation (r = -0.52) and the slope of ventilation against CO2 production correlated with M mode isovolumic relaxation time (r = 0.61).

CONCLUSIONS

In patients with systolic left ventricular dysfunction, more than half the variance in exercise tolerance can be predicted by factors measured on echocardiography at rest, particularly right ventricular long axis excursion.

Utility of CT scan evaluation for predicting pulmonary hypertension in patients with parenchymal lung disease. Medical College of Wisconsin Lung Transplant Group

OBJECTIVE

To determine the utility of CT-determined main pulmonary artery diameter (MPAD) for predicting pulmonary hypertension (PH) in patients with parenchymal lung disease.

DESIGN

Retrospective review of right-heart hemodynamic data and chest CT scans in 45 patients.

SETTING

Tertiary-referral teaching hospital and VA hospital.

PATIENTS

Between October 1990 and December 1995, 36 patients referred for evaluation of parenchymal lung disease or possible pulmonary vascular disease were found to have PH, as defined by mean pulmonary artery pressure (mPAP) > or =20 mm Hg. Nine control patients (mPAP <20 mm Hg) were also identified (4 from hospital records search, 5 after evaluation for possible PH).

RESULTS

CT-determined MPAD was 35+/-6 mm in patients with PH and 27+/-2 mm in control subjects. In our group of patients, MPAD > or =29 mm had a sensitivity of 87%, specificity of 89%, positive predictive value (PPV) of 0.97, and positive likelihood ratio (LR) of 7.91 for predicting PH; in the subgroup of patients with parenchymal lung disease (n=28, PH and control subjects), MPAD > or =29 mm had a sensitivity of 84%, specificity of 75%, PPV of 0.95, and positive LR of 3.36 for predicting PH. The most specific findings for the presence of PH were both MPAD > or =29 mm and segmental artery-to-bronchus ratio > 1:1 in three or four lobes (specificity, 100%). There was no linear correlation between the degree of PH and MPAD (r=0.124).

CONCLUSIONS

CT-determined MPAD has excellent diagnostic value for detection of PH in patients with advanced lung disease. Therefore, standard chest CT scans can be used to screen for PH as a cause of exertional limitation in patients with parenchymal lung disease. Because CT is commonly used to evaluate parenchymal lung disease, this information is readily available.

Echocardiographic assessment of long axis function: a simple solution to a complex problem?

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