Instantaneous pressure-flow velocity relations of systemic venous return in patients with univentricular circulation

OBJECTIVE—To assess the pressure and flow velocity relations and respiratory variability of the systemic venous and hepatic venous return in patients with univentricular circulation.
PATIENTS—15 selected patients who had undergone cavopulmonary anastomosis (10) or atriopulmonary anastomosis (5). Mean age at operation was 55.1 months (range 9 to 145). Studies were done at 75.5 (32.6) months (mean (SD)) after the operation.
SETTING—Tertiary referral centre.
METHODS—Patients were studied using simultaneous recordings of ECG, pressure trace, respirometer trace, and pulsed Doppler echocardiography. Mean systemic venous pressure and pulmonary vascular resistance did not differ significantly between the two patient groups.
RESULTS—After total cavopulmonary anastomosis, systemic venous pressure tracings showed a flattened pressure curve without any dependence on cardiac or respiratory cycle. After atriopulmonary anastomosis, right atrial pressure tracings showed a significantly higher "a" wave corresponding to atrial contraction, without any respiratory variability. Pulsed Doppler examination of the superior and inferior caval vein and hepatic vein after total cavopulmonary anastomosis did not show a reverse flow after atrial contraction. The inspiratory to expiratory velocity ratio of antegrade flow revealed a significant dependence of flow on changes in intrathoracic pressure in the intra-atrial tunnel, caval veins, and hepatic vein. During expiration, decrease or cessation of antegrade hepatic venous flow was documented. After an atriopulmonary anastomosis, there was a biphasic antegrade venous flow pattern without significant respiratory variation.
CONCLUSIONS—After total cavopulmonary anastomosis, there was marked respiratory dependence of systemic and hepatic venous return, whereas after an atriopulmonary anastomosis venous flow pattern varied according to cardiac cycle and pressure trace. The effects of total cavopulmonary anastomosis on venous return might counteract its other haemodynamic advantages.


Keywords: Fontan operation; Doppler echocardiography; systemic venous flow pattern     

Short term effect of continuous positive airway pressure on muscle sympathetic nerve activity in patients with chronic heart failure

OBJECTIVE—To test the hypothesis that the short term application of continuous positive airways pressure (CPAP) increases muscle sympathetic nerve activity in patients with congestive heart failure.
SETTING—University hospital and tertiary referral centre.
PATIENTS—10 patients with congestive heart failure (New York Heart Association functional class III; mean (SEM) left ventricular ejection fraction 22 (1)%) and 10 healthy subjects matched for age, sex, and weight.
MAIN OUTCOME MEASUREMENTS—Muscle sympathetic nerve activity, assessed by microneurography of the peroneal nerve, blood pressure, heart rate, minute ventilation, transcutaneous oxygen saturation, and end tidal PCO₂ were measured during normal breathing, mask breathing, and CPAP at 5 and 10 cm H₂O.
RESULTS—CPAP induced an increase in muscle sympathetic nerve activity and blood pressure in both the patients and the control subjects. In the patients, sympathetic nerve activity increased from 43 (14) bursts/min during mask breathing to 47 (13) bursts/min at CPAP 10 cm H₂0 (p = 0.03); mean blood pressure increased from 80 (3) mm Hg to 86 (4) mm Hg (p < 0.001). Oxygen saturation improved during CPAP in the patients, from 95.7 (0.6)% to 96.6 (0.7)% (p = 0.004) and remained stable in the control group. There was no effect of CPAP on minute ventilation or heart rate.
CONCLUSIONS—In patients with congestive heart failure, short term CPAP elicits sympathetic activation, probably because of unloading of the aortic or cardiopulmonary baroreceptors.


     

Definitive palliation with cavopulmonary or aortopulmonary shunts for adults with single ventricle physiology

OBJECTIVE—To compare the relative merits of cavopulmonary or aortopulmonary shunts, or both, as definitive non-Fontan palliations for patients with single ventricle physiology.
DESIGN—Clinical data, ECG, echocardiographic data, surgical records, and available postmortem material were reviewed in all patients with single ventricle physiology identified from the University of Toronto Congenital Cardiac Centre for Adults (UTCCCA) database who had not undergone a Fontan operation. Current status of patients was assessed from clinic reviews and patient contact. Two groups of patients were identified: those with cavopulmonary shunt (group 1, n = 35); and those with aortopulmonary shunt(s) only (group 2, n = 15).
RESULTS—50 adults (21 male/29 female) who underwent the last palliation at a median age of 11 years (range 1 day to 53 years) were identified. During a mean (SD) follow up of 13.0 (6.2) years at the UTCCCA, 19 patients died. Survival is 89.4% and 51.9% at 10 and 20 years, respectively, from the time patients were first seen at UTCCCA, with no differences between the groups. Most recent New York Heart Association (NYHA) classification was I-II in 21 patients, III in 25, and IV in four patients; mean haemoglobin was 190 (28) g/l, and oxygen saturation was 82 (4)%, with no group differences. Arrhythmia developed in 25 patients (atrial flutter/fibrillation in 20 and/or sustained ventricular tachycardia in 11). Atrial flutter/fibrillation was more common in patients in group 2, who also showed a greater decline in ventricular function with time. Age at last palliation, cardiothoracic ratio, and inclusion in group 2 were predictive of atrial flutter/fibrillation, poor ventricular function predictive of ventricular tachycardia, NYHA class > III, and prior ventricular tachycardia predictive of death.
CONCLUSIONS—Cavopulmonary or aortopulmonary shunts, or both, provide sustained palliation for selected patients with single ventricle physiology. Survival for both compares favourably with published Fontan series. Compared to aortopulmonary shunts, cavopulmonary shunts convey a beneficial long term effect on ventricular function. Arrhythmia is a major cause of late morbidity in these patients, relating to both ventricular dysfunction and death. Onset of sustained ventricular tachycardia is an ominous sign.


     

Lewis phenotypes, leisure time physical activity, and risk of ischaemic heart disease: an 11 year follow up in the Copenhagen male study

OBJECTIVE—To test the hypothesis that the predictive value for risk of fatal ischaemic heart disease associated with Lewis phenotypes depends on the level of leisure time physical activity.
DESIGN—Prospective study controlling for alcohol, tobacco, serum cotinine, blood pressure, body mass index, serum lipids, work related physical activity, and social class.
SETTING—The Copenhagen male study, Denmark.
SUBJECTS—2826 white men aged 53-75 years without overt cardiovascular disease; 266 (9.4%) had the Le(a−b−) phenotype.
MAIN OUTCOME MEASURE—Incidence of death from ischaemic heart disease during 11 years.
RESULTS—107 men died of ischaemic heart disease. Among men with a low level of leisure time physical activity (⩽ 4 hours/week moderate or ⩽ 2 hours/week more vigorous activity), being Le(a−b−) was associated with an increased risk of having a fatal ischaemic heart disease event compared with men with other Lewis phenotypes (relative risk (RR) 2.7, 95% confidence interval (CI) 1.4 to 5.2; p < 0.01). Among men with a high level of leisure time physical activity, the RR associated with being Le(a−b−) was 1.3 (95% CI 0.5 to 3.1; NS). Compared with all other alternatives tested, being Le(a−b−) and having a low level of leisure time physical activity was associated with an RR of 3.2 (95% CI 1.7 to 5.8; p < 0.001). As a point estimate and adjusted for confounding variables, among men with low leisure time physical activity the attributable risk associated with Le(a−b−) was 12%—that is, assuming that all sedentary men had phenotypes other than Le(a−b−), 12% of all fatal ischaemic heart disease events would not have occurred. The corresponding point estimate among those more active was 2%.
CONCLUSIONS—The excess risk of fatal ischaemic heart disease in middle aged and elderly men with the Le(a−b−) phenotype is strongly modified by leisure time physical activity. Public health and clinical implications may be important in populations with a predominantly sedentary lifestyle and in a high proportion of men with the Le(a−b−) phenotype.


     

The Fontan procedure in adults

SETTING—Tertiary adult congenital cardiac referral centre.
DESIGN—Retrospective cross sectional analysis.
OBJECTIVES—To report our 20 year experience with adult Fontan operations, and to compare late outcome in patients with single ventricle with definitive aortopulmonary or cavopulmonary shunt palliation.
PATIENTS AND MAIN OUTCOME MEASURES—Patients older than 18 years undergoing Fontan operation between 1 January 1982 and 31 December 1998 were identified. Mortality and late outcome were derived from hospital records. These patients were compared with a cohort of 50 adults with single ventricle who had not undergone a Fontan operation.
RESULTS—61 adults, median age 36 years (range 18-47 years), with a median follow up of 10 years (range 0-21 years) were identified. Actuarial survival was 80% at one year, 76% at five years, 72% at 10 years, and 67% at 15 years. Compared with before the Fontan operation, more patients were in New York Heart Association (NYHA) functional class I or II at the latest follow up (80% v 58%, p < 0.001). Systolic ventricular function deteriorated during follow up such that 34% had moderate to severe ventricular dysfunction at the latest follow up compared with 5% before Fontan (p < 0.001). Arrhythmia increased with time (10% before Fontan v 57% after 10 years, p < 0.001). Fontan patients had improved NYHA functional class, ventricular function, atrioventricular regurgitation, and fewer arrhythmias than the non-Fontan group at the latest follow up.
CONCLUSION—The Fontan operation in adults has acceptable early and late mortality. Functional class, systolic ventricular function, atrioventricular regurgitation, and arrhythmia deteriorate late after surgery but to a lesser degree than in non-Fontan patients with a single ventricle.


     

Relative contribution of resting haemodynamic profile and lung function to exercise tolerance in male patients with chronic heart failure

OBJECTIVE—To clarify the relative contribution of resting haemodynamic profile and pulmonary function to exercise capacity in patients with heart failure.
SETTING—Cardiology department and cardiac rehabilitation unit in a tertiary centre.
DESIGN—161 male patients (mean (SD) age 59 (9) years) with heart failure (New York Heart Association class II-IV, left ventricular ejection fraction 23 (7)%) underwent spirometry, alveolar capillary diffusing capacity (DLCO), and mouth inspiratory and expiratory pressures (MIP, MEP, respectively, in 100 patients). Right heart catheterisation and a symptom limited cardiopulmonary exercise test were performed in 137 patients within 3-4 days.
RESULTS—Mean peak exercise oxygen consumption (V̇O₂) was 13 (3.9) ml/kg/min. Among resting haemodynamic variables only cardiac index showed a significant correlation with peak V̇O₂. There were no differences in haemodynamic variables between patients with peak V̇O₂ ⩽ or > 14 ml/kg/min. There was a moderate correlation (p < 0.05) between several pulmonary function variables and peak V̇O₂. Forced vital capacity (3.5 (0.9) v 3.2 (0.8) l, p < 0.05) and DLCO (21.6 (6.9) v 17.7 (5.5) ml/mm Hg/min, p < 0.05) were higher in patients with peak V̇O₂ > 14 ml/kg/min than in those with peak V̇O₂ ⩽ 14 ml/kg/min. Using a stepwise regression analysis, the respiratory and haemodynamic variables which correlated significantly with peak V̇O₂ were DLCO, MEP, and cardiac index, with an overall R value of 0.63.
CONCLUSIONS—The data confirm previous studies showing a poor correlation between resting indices of cardiac function and exercise capacity in heart failure. However, several pulmonary function variables were related to peak exercise V̇O₂. In particular, lung diffusing capacity and respiratory muscle function seem to affect exercise tolerance during heart failure.


     

Coronary revascularisation for postischaemic heart failure: how myocardial viability affects survival

OBJECTIVE—To assess the impact of revascularisation of viable myocardium on survival in patients with postischaemic heart failure.
METHODS—35 patients (mean (SD) age 58 (7) years) with severe heart failure (New York Heart Association (NYHA) functional class ⩾ III), mean left ventricular ejection fraction (LVEF) 24 (7)% (range 10-35%), and limited exercise capacity (peak oxygen consumption (VO₂) 15 (4) ml/kg/min) were studied. 21/35 patients had no angina. Myocardial viability was assessed with quantitative positron emission tomography and the glucose analogue ¹⁸F-fluorodeoxyglucose (FDG) (viable segment = FDG uptake ⩾ 0.25 µmol/min/g) in all patients before coronary artery bypass grafting. Patients were divided into two groups: group 1, ⩾ 8 viable dysfunctional segments (mean 12 (2), range 8-15); and group 2, < 8 viable dysfunctional segments (mean 3.5 (3), range 0-7). The two groups were comparable for age, sex, NYHA class, LVEF, and peak VO₂.
RESULTS—Two patients died perioperatively and seven patients died during follow up (mean 33 (14) months). All deaths were from cardiac causes. Kaplan-Meyer survival analysis showed 86% survival for group 1 patients versus 57% for group 2 (p = 0.03). Analysis by Cox proportional hazard model revealed three independent factors for cardiac event free survival: presence of ⩾ 8 viable segments (p = 0.006); preoperative LVEF (p = 0.002); and patient age (p = 0.01).
CONCLUSION—Revascularisation for postischaemic heart failure can be associated with good survival, which is critically dependent upon the amount of viable myocardium.


     

Haemodynamic correlates and prognostic significance of serum uric acid in adult patients with Eisenmenger syndrome

OBJECTIVE—To assess haemodynamic correlates and prognostic significance of serum uric acid in adult patients with Eisenmenger syndrome.
DESIGN—Retrospective observational study.
SETTING—Tertiary referral centre.
PATIENTS—94 adult patients with Eisenmenger syndrome who were diagnosed between September 1982 and July 1998.
MAIN OUTCOME MEASURES—Serum uric acid was measured in all patients, together with clinical and haemodynamic variables related to mortality.
RESULTS—Serum uric acid was raised in patients with Eisenmenger syndrome compared with age and sex matched control subjects (7.0 v 4.7 mg/dl, p < 0.0001) and increased in proportion to the severity of New York Heart Association functional class. Serum uric acid was positively correlated with mean pulmonary arterial pressure (r = 0.30, p = 0.0052) and total pulmonary resistance index (r = 0.55, p < 0.0001), and negatively correlated with cardiac index (r = −0.50, p < 0.0001). During a mean follow up period of 97 months, 38 patients died of cardiopulmonary causes. Among various clinical, echocardiographic, and laboratory variables, serum uric acid remained predictive in multivariate analysis. Kaplan-Meier survival curves based on median serum uric acid showed that patients with high values had a significantly worse survival rate than those with low values (log-lank test: p = 0.0014 in male patients, p = 0.0034 in female patients).
CONCLUSIONS—Serum uric acid increases in proportion to haemodynamic severity in adult patients with Eisenmenger syndrome and is independently associated with long term mortality.


     

"Value" of improved treadmill exercise capacity: lessons from a study of rate responsive pacing

Objective—To assess outcomes of pacemaker upgrade from single chamber ventricular to dual chamber.
Design—Retrospective analysis of patients undergoing the procedure.
Setting—Specialist cardiothoracic unit.
Patients—44 patients (15 female, 29 male), mean (SD) age at upgrade 68.2 (12.9) years.
Interventions—Upgrade of single chamber ventricular to dual chamber pacemaker.
Main outcome measures—Procedure duration and complications.
Results—Principal indications for upgrade were pacemaker syndrome (17), "opportunistic"—that is, at elective generator replacement (8), heart failure (7), non-specific breathlessness/fatigue (7), and neurally mediated syncope (3). Mean (SD) upgrade procedure duration (82.9 (32.6) minutes) significantly exceeded mean VVI implantation duration (42.9 (13.3) minutes) and mean DDD implantation duration (56.6 (22.7) minutes) (both p < 0.01). Complications included pneumothorax (1), ventricular arrhythmia requiring cardioversion (2), protracted procedure (10), atrial lead repositioning within six weeks (8), haematoma evacuation (1), superficial infection (1), and admission to hospital with chest pain (1); 20 patients (45%) suffered one or more complications including four of the eight who underwent opportunistic upgrade.
Conclusions—Pacemaker upgrade takes longer and has a higher complication rate than either single or dual chamber pacemaker implantation. This suggests that the procedure should be performed by an experienced operator, and should be undertaken only if a firm indication exists. Patients with atrial activity should not be offered single chamber ventricular systems in the belief that the unit can be upgraded later if necessary at minimal risk.

     

Relation between duration and intensity of first exercise and "warm up" in ischaemic heart disease

OBJECTIVE—To determine the importance of the duration and intensity of "warm up" exercise for reducing ischaemia during second exercise in patients with exertional angina.
DESIGN—Randomised crossover comparison of three warm up exercise protocols.
PATIENTS—18 subjects with stable ischaemic heart disease and > 0.1 mV ST segment depression on treadmill exercise testing.
INTERVENTIONS—The warm up protocols were 20 minutes of slow exercise at 2.7 km/h, symptom limited graded exercise for a mean of 7.4 (range 5.0 to 10.5) minutes, and three minutes of symptom limited fast exercise of similar maximum intensity.
MAIN OUTCOME MEASURES—ST segment depression during graded treadmill exercise undertaken 10 minutes after each warm up protocol or no warm up exercise.
RESULTS—Compared with exercise with no warm up, the duration of graded exercise after earlier slow warm up increased by 4.9% (95% confidence interval (CI), −3.3% to 13.7%), after graded warm up by 10.3% (95% CI, 5.6% to 15.2%), and after fast warm up by 16% (95% CI, 6.2% to 26.7%). ST segment depression at equivalent submaximal exercise decreased after slow warm up by 27% (95% CI, 5% to 44%), after graded warm up by 31% (95% CI, 17% to 44%), and after fast warm up by 47% (95% CI, 27% to 61%). Compared with slow warm up exercise, the more intense graded and fast warm up protocols significantly increased the duration of second exercise (p = 0.0072) and reduced both peak ST depression (p = 0.0026) and the rate of increase of ST depression (p = 0.0069).
CONCLUSIONS—In patients with exertional angina the size of the warm up response is related to the maximum intensity rather than the duration of first exercise.


     

Significance of commissural calcification on outcome of mitral balloon valvotomy

OBJECTIVE—To evaluate the significance of commissural calcification, identified by transthoracic echocardiography, on the haemodynamic and symptomatic outcome of mitral balloon valvotomy.
METHODS—Commissural calcification was graded from 0-4 using parasternal short axis transthoracic views. The morphology of the mitral valve was also assessed using the Massachusetts General Hospital echo score.
SETTING—A tertiary cardiac centre in Scotland.
PATIENTS—300 patients were studied, 85 retrospectively and 215 prospectively. Mean (SD) age was 59.8 (12.7) years, range 13 to 87; 30% had been judged unsuitable for surgery. Median echo score was 6.8 (3.0), range 2-16.
MAIN OUTCOME MEASURES—Immediate increase in mitral valve area and in New York Heart Association functional class 1-3 months after balloon valvotomy.
RESULTS—On univariate and multivariate analysis, commissural calcification grade was a significant predictor of achieving a mitral valve area of > 1.50 cm² without severe mitral reflux. Its influence was greatest in patients with an echo score ⩽ 8: those with commissural calcification grade 0/1 had significantly greater improvement in valve area and symptom status than those with grade 2/3; the proportions of patients achieving a final valve area of > 1.50 cm² were 67% and 46%, respectively (p < 0.05). In patients with an echo score of > 8, the influence of commissural calcification was smaller and not significant.
CONCLUSIONS—Commissural calcification as assessed by transthoracic echocardiography is a useful predictor of outcome in patients with otherwise "good" valves (echo score ⩽ 8). Calcification of one commissure or more predicts a less than 50% probability of achieving a valve area above 1.50 cm² and is an indication for valve replacement in those who are suitable for surgery.


     

Heart rate variability and baroreflex sensitivity in idiopathic dilated cardiomyopathy

OBJECTIVE—To examine the relation between cardiac autonomic tone, assessed by baroreflex sensitivity and heart rate variability, and left ventricular function, arrhythmias on Holter monitoring, and clinical variables in patients with idiopathic dilated cardiomyopathy.
DESIGN—A prospective observational study.
PATIENTS—160 patients with idiopathic dilated cardiomyopathy and preserved sinus rhythm in the absence of antiarrhythmic drug treatment. Measures of heart rate variability obtained by digital 24 hour Holter recordings included the mean of all coupling intervals between normal beats (RRm), the standard deviation of the mean of normal RR intervals (SDNN), and the square root of the mean of the squared differences between adjacent normal RR intervals (rMSSD). Baroreflex sensitivity testing was performed using the phenylephrine method.
RESULTS—Mean SDNN (SEM) was 112 (46) ms, and baroreflex sensitivity was 7.5 (5.0) ms/mm Hg. SDNN showed a weak correlation with baroreflex sensitivity (r = 0.19, p < 0.05) and with left ventricular ejection fraction (r = 0.29, p < 0.05). SDNN showed no significant correlation with age (r = −0.07), the presence of non-sustained ventricular tachycardia (r = −0.13), or left ventricular end diastolic diameter (r = −0.07). In addition, baroreflex sensitivity showed no significant correlation with age (r = −0.13), non-sustained ventricular tachycardia (r = −0.08), left ventricular end diastolic diameter (r = 0.09), or ejection fraction (r = 0.14).
CONCLUSIONS—The weak correlation between baroreflex sensitivity and heart rate variability suggests that these two indices explore different aspects of cardiac autonomic control in patients with idiopathic dilated cardiomyopathy. The weak or absent correlation between baroreflex sensitivity, heart rate variability, and other potential non-invasive risk predictors, including left ventricular ejection fraction, left ventricular end diastolic diameter, and non-sustained ventricular tachycardia on Holter monitoring, indicate that these variables may have independent prognostic value in idiopathic dilated cardiomyopathy.


Keywords: cardiomyopathy; baroreflex sensitivity; heart rate variability     

High prevalence of arrhythmias in elderly male athletes with a lifelong history of regular strenuous exercise

Objective—To characterise cardiac arrhythmias and cardiac autonomic function in 11 elderly men (mean (SD) age 73.2 (2.8) years) with a lifelong history of regular very strenuous exercise. A control group of 12 healthy sedentary or moderately physically active men (74.5 (2.7) years) was also studied.
Design—48 hour ambulatory electrocardiograms were recorded. Cardiac autonomic function was estimated from power spectral analysis of heart rate variability. Maximal oxygen uptake during treadmill exercise testing was 2.91 (0.52) l (41 (7) ml/kg).
Results—Nine of 11 athletes had complex ventricular arrhythmias compared with five of 12 controls. Seven athletes but none of the controls had episodes of heart rate below 40 beats/min and two athletes had RR intervals longer than two seconds. Heart rate variability in the athletes was higher than in the controls.
Conclusions—Elderly athletes with a lifelong training history seem to have more complex arrhythmias and profound bradyarrhythmias than do healthy elderly controls, which may increase the risk of sudden cardiac death. In contrast, the age related decrease in heart rate variability seems to be retarded, which has a positive prognostic value and may decrease the risk of life threatening ventricular arrhythmias.

Keywords: arrhythmias;  heart rate variability;  athletes;  exercise;  elderly men     

Abnormal cardiopulmonary exercise variables in asymptomatic relatives of patients with dilated cardiomyopathy who have left ventricular enlargement

BACKGROUND—Left ventricular enlargement with normal systolic function is common in asymptomatic relatives of patients with familial dilated cardiomyopathy, many of whom progress to overt dilated cardiomyopathy at follow up.
OBJECTIVE—To examine maximal and submaximal gas exchange variables of cardiopulmonary exercise testing in asymptomatic relatives with left ventricular enlargement.
DESIGN AND SETTING—Controlled evaluation of metabolic exercise performance of patients with dilated cardiomyopathy and asymptomatic relatives with left ventricular enlargement identified through prospective family screening in a cardiomyopathy outpatient clinic.
METHODS—23 relatives with left ventricular enlargement, 33 normal controls, 29 patients with dilated cardiomyopathy, and 10 elite athletes with echocardiographic criteria of left ventricular enlargement ("physiological" enlargement) underwent symptom limited upright cycle ergometry using a ramp protocol.
RESULTS—Peak oxygen consumption (pO₂; mean (SD)) was significantly reduced in relatives with left ventricular enlargement (78 (16.3)%) v normal controls (96%, p < 0.01) and athletes (152%, p < 0.001), but was higher than in patients with dilated cardiomyopathy (69%, p < 0.01). pO₂ was less than 80% of predicted in 75% of patients, 58% of relatives, 22% of controls, and none of the athletes. Oxygen pulse (pO₂/heart rate) was less than 80% of predicted in 69% of patients, 35% of relatives, 6% of controls, and none of the athletes. The slope of minute ventilation v CO₂ production (ΔVE/ΔCO₂) was > 30 in 68% of patients, 50% of relatives, and in none of the controls or athletes. Anaerobic threshold, occurring in relatives at 37 (14)% of the predicted O₂, was higher than in the patients (32%, p < 0.01) and lower than in the controls (45%, p < 0.05) or in the athletes (55%, p < 0.001).
CONCLUSIONS—Maximal and submaximal cardiopulmonary exercise test variables are abnormal in asymptomatic relatives with left ventricular enlargement, in spite of normal systolic function. This provides further evidence that left ventricular enlargement represents subclinical disease in relatives of patients with dilated cardiomyopathy. Metabolic exercise testing can complement echocardiography in identifying relatives at risk for the development of dilated cardiomyopathy.


     

Morphology of perforated atrial septal aneurysm suitable for closure by transcatheter device placement

OBJECTIVE—To define the morphological criteria of perforated atrial septal aneurysms suitable for closure by a transcatheter device.
METHODS—A retrospective analysis of all consecutive patients with atrial septal aneurysm and one or more perforations presenting between May 1997 and June 1999. The aneurysms were classified as: aneurysm with persistent foramen ovale (type A); aneurysm with single atrial septal defect (type B); aneurysm with two perforations requiring more than one device for closure (type C); and aneurysm with multiple perforations (type D).
PATIENTS—Data from 50 patients aged 5-78 years (mean 43 years) were analysed; 32 had systemic thromboembolism or transient ischaemic attacks, eight presented with dyspnoea on exercise, and 10 were discovered incidentally but had significant left to right shunt and right ventricular volume overload.
RESULTS—In all 18 patients with aneurysm and persistent foramen ovale (type A), transcatheter closure was possible. In nine with aneurysm and atrial septal defect (type B), five defects were closed and four required surgery. Device closure was achieved in all 10 patients with aneurysms and two perforations (type C), but four had a residual shunt. Thirteen patients with multiple perforated aneurysms (type D) underwent surgery.
CONCLUSIONS—This classification of morphology of perforations of aneurysm is clinically useful for selecting patients for treatment by transcatheter devices.