A comparison of wall motion analysis and systolic left ventricular long axis function during dobutamine stress echocardiography.

AIMS: To compare long-axis function and wall motion analysis for the detection of significant coronary artery stenoses in patients with single and multivessel disease. METHODS AND RESULTS: We performed dobutamine stress echocardiography in 67 subjects, 14 with normal coronary anatomy, and 53 with significant coronary disease. A blunted increase in mean long-axis shortening of <0.25 cm was the best discriminator for coronary artery disease (sensitivity 85%, specificity 81%). Using this threshold, long axis function gave a sensitivity of 88% and specificity 89% for the detection of coronary artery disease in patients with normal resting wall motion while wall motion abnormality analysis had a sensitivity 73% and specificity 94%. Of 26 patients with a resting wall motion abnormality, 14 (54%) had multivessel disease. Long axis function detected multivessel disease in 12 of these (sensitivity 86%) compared with nine (sensitivity 64%) for wall motion analysis. CONCLUSION: Long axis function provides a promising, quantitative adjunct to wall motion analysis for the detection of coronary ischaemia using dobutamine stress echocardiography in patients with single and multivessel disease and with resting wall motion abnormalities.

Is there a place for the late cardioversion of atrial fibrillation? A long-term follow-up study of patients with post-thyrotoxic atrial fibrillation.

AIMS: As atrial fibrillation is associated with significant mortality and morbidity, restoration of sinus rhythm is desirable. However, previous data suggest that cardioversion should be restricted to patients in whom the fibrillation is of limited duration (<1-2 years) because of high relapse rates. It may be the frequent association with cardiac disease, rather than the duration of fibrillation itself, which determined the high relapse of earlier studies. The aim of this study was to investigate rates of cardioversion, maintenance of sinus rhythm and predictors of subsequent relapse in a homogeneous group of patients without evidence of any co-existent cardiac disease. METHODS AND RESULTS: We report on a retrospective series of 106 patients with thyrotoxicosis-induced fibrillation but no other heart disease: 87% had been in atrial fibrillation for >12 months (median duration 28.5, interquartile range 15-47 months). Cardioversion was attempted using disopyramide and then electric shock. Ninety-eight patients were successfully cardioverted: at late follow-up, 80.6+/-37 months (mean+/-SD), 67% were in sinus rhythm. CONCLUSION: Although a relationship between the duration of fibrillation and maintenance of sinus rhythm was found, the high proportion remaining in sinus rhythm, compared with other series, suggests this influence may be less important than the presence or absence of structural heart disease.

Coronary endothelial function in cardiac transplant recipients with accelerated coronary disease.

BACKGROUND: Previous studies with the endothelium-dependent vasodilator substance P have shown a preserved vasodilator response in cardiac transplant recipients with angiographically normal coronary arteries. Although endothelial dysfunction is known to occur in cardiac transplant recipients with accelerated coronary disease, the degree to which the endothelium is affected is not known precisely. The aim of the present study was to examine endothelial function in accelerated coronary disease following cardiac transplantation. METHODS: Thirteen cardiac transplant recipients with epicardial coronary disease underwent substance P infusion. The response to incremental doses of substance P was measured in smooth segments of affected coronary arteries. Substance P was infused over 2 min with a starting dose of 1.4 pmol/min and a maximum of 22.4 pmol/min, reached by doubling the dose in steps, followed by an infusion of 2 mg isosorbide dinitrate over 2 min. RESULTS: Substance P caused less vasodilation at lower concentrations, with a significantly higher dose required to achieve half maximal dilation compared with cardiac transplant recipients with no coronary disease. The mean maximal dilatation achieved with substance P was 22.98 +/- 4.62% compared to 21.95 +/- 4.9% with isosorbide dinitrate; the latter value was not significantly different from the maximal dilation achieved in cardiac transplant recipients without coronary disease. CONCLUSIONS: In cardiac transplant recipients with accelerated coronary disease the functional vasodilatory ability of the coronary endothelium is impaired in segments of apparently unaffected epicardial arteries, which may lead to an increase in the resting vasoconstrictor tone and have important functional and therapeutic implications.

Relationship between myocardial collagen and echo amplitude in non-fibrotic hearts.

The aim of the study was to investigate the relationship between myocardial collagen and regional echo amplitude in humans with non-fibrotic myocardium. The ratio of myocardial collagen to total myocardial protein was determined as the hydroxyproline/leucine ratio in endomyocardial biopsies obtained from the right ventricular side of the interventricular septum in orthotopically transplanted hearts. Regional echo amplitude was measured in the interventricular septum. Patients were studied prospectively. Twenty-five patients (five female, 20 male) who had undergone orthotopic cardiac transplantation were studied 355 to 2939 days (1009 +/- 718, mean +/- SD) post-transplantation at the time of annual cardiac catheterization and endomyocardial biopsy. Patient ages varied from 22 to 62 years (46 +/- 11). Donor ages were 14 to 47 years (25 +/- 8) and the ischaemic time, 90 to 245 min (151 +/- 42). Cardiac transplantation was performed for end-stage cardiac failure in all patients. The aetiology of cardiac failure was valvular heart disease in three, dilated cardiomyopathy in eight and ischaemic heart disease in the remainder. Echo amplitude studies were performed within 24 h of endomyocardial biopsy. All but one patient were on an immunosuppressive regime consisting of cyclosporine A and azathioprine with additional steroids in three. The remaining patient, who was the longest surviving patient in the study group, had never been treated with cyclosporine. This patient was maintained on steroids and azathioprine alone. No patient had clinical or histological evidence for acute cardiac rejection and all were clinically well. Five patients had angiographic evidence of coronary artery disease. All subject studies were performed at Harefield Hospital.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler examination of superior vena caval flow for the detection of acute cardiac rejection.

BACKGROUND: Doppler echocardiographic studies have previously documented abnormalities of mitral flow during acute rejection similar to those seen in patients with "restrictive" physiology. As central venous flow is known to be abnormal in such patients, it was proposed that examination of superior vena caval flow with Doppler echocardiography might be useful for the detection of acute cardiac rejection. METHODS AND RESULTS: Thirty orthotopic cardiac transplant patients, 15 of whom had acute cardiac rejection diagnosed by endomyocardial biopsy, were studied within 36 hours of biopsy. Superior vena caval Doppler flow velocities as well as mitral and tricuspid flow velocities were recorded using a Hewlett-Packard Sonos 500/1000 echocardiograph system. Examinations were performed blinded to the biopsy result. Mitral and tricuspid peak early flow velocities in the nonrejector group were similar to those seen in normal subjects (mitral, 70 +/- 5 cm/sec; tricuspid midexpiratory apnea, 50 +/- 11 cm/sec). Superior vena caval flow was abnormal with 13 of 15 patients demonstrating a biphasic pattern of forward flow with dominant diastolic flow. In the 15 patients with acute cardiac rejection, both mitral and tricuspid flow velocities developed a "restrictive"-type pattern with increased peak early flow velocities (mitral, 89 +/- 24 cm/sec; tricuspid midexpiratory apnea, 63 +/- 19 cm/sec; p < or = 0.05 versus nonrejectors) and decreased mitral early flow-velocity deceleration times (rejectors, 97 +/- 26 msec; nonrejectors, 144 +/- 41 msec; p < or = 0.05). The pattern of superior vena caval flow became markedly abnormal with a virtually complete loss of forward systolic flow (rejectors, 4.4 +/- 6.6 cm/sec; nonrejectors, 26.1 +/- 8.8 cm/sec at midexpiratory apnea; p < or = 0.0001). In 10 of 15 patients, systolic forward flow was absent. If acute rejection was defined as forward systolic flow < or = 17 cm/sec, then sensitivity was 100%, specificity was 80%, and predictive accuracy was 90%. CONCLUSIONS: During acute cardiac rejection, forward systolic superior vena caval flow is markedly diminished compared with nonrejectors. This is accompanied by other Doppler echocardiographic features consistent with the development of "restrictive" physiology. It is postulated that the loss of forward systolic flow in the superior vena cava is due to diminished long-axis shortening of the right ventricle associated with acute cardiac rejection.

Changes in myocardial echo amplitude during reversible ischaemia in humans.

OBJECTIVE: This study investigated the changes in regional myocardial ultrasonic backscatter, measured as myocardial echo amplitude, that occur during reversible myocardial ischaemia in humans. DESIGN: Left anterior descending coronary angioplasty was used to produce reversible myocardial ischaemia in human subjects. Regional myocardial echo amplitude was studied in the interventricular septum and left ventricular posterior free wall before, during, and after coronary occlusion with the angioplasty balloon. Wall motion analysis of the left ventricle was performed from simultaneous cross sectional echocardiographic imaging. Patients were studied prospectively. PATIENTS: Six patients (mean age 56 (SD 11), range 46 to 69 years) with single vessel, left anterior descending coronary artery stenoses, were investigated during elective coronary angioplasty. A total of 11 balloon inflations were studied. SETTING: All patient studies were performed at Harefield Hospital. Echo amplitude analysis was performed at the Royal Brompton Hospital. INTERVENTIONS: Angioplasty was performed by the usual procedure at Harefield Hospital for elective coronary angioplasty. All routine medication including beta blockers and calcium antagonists were continued. Inflation pressures were up to 12 atm (1212 kPa) and mean inflation time ranged from 30 to 120 (86 (31)) s. In four studies the first inflation was examined, in three the second, in two the third, and in one each the fourth and fifth inflations. Echo amplitude and cross sectional echo-cardiographic studies were recorded with a 3.5 MHz Advanced Technology Laboratories (ATL) (720A/8736 series) mechanical sector scanner and an ATL Mark III (860-1 series) echocardiograph system with 45 dB logarithmic grey scale compression. MAIN OUTCOME MEASURES: Regional echo amplitude was examined in four regions of the left ventricle--namely, the basal and mid-septum, and basal and mid-posterior wall. Consecutive end diastolic and end systolic frames were analysed and cyclic variation was determined as the difference between the level of echo amplitude at end diastole and at end systole. Measurements were made before balloon inflation, at peak inflation, and after balloon deflation. Regional wall motion and systolic wall thickening were analysed qualitatively. RESULTS: Before balloon inflation, cyclic variation in echo amplitude was noted in all regions (basal septum, 2.4 (SD 1.1) dB; mid-septum, 2.5 (1.1) dB; basal posterior wall, 3.3 (2.1) dB; mid-posterior wall, 3.9 (1.6) dB). During balloon inflation there was a significant fall in cyclic variation to 0.4 (0.9) dB (p < 0.0002) in the mid-septum. This was predominantly owing to an increase in end systolic echo amplitude from 5.4 (2.0) dB to 9.3 (1.9) dB (p < or = 0.01). This was associated with the development of severe hypokinesis or akinesis in the mid-septum. No significant changes in echo amplitude occurred in the three other regions examined. Changes were completely reversed after balloon deflation. CONCLUSIONS: These results suggest a causal relation between occlusion of the supplying coronary artery and blunting of myocardial echo amplitude cyclic variation. It is suggested that balloon occlusion produced myocardial ischaemia. The resultant impairment of myocardial contraction then caused a blunting of cyclic variation in echo amplitude. The results of this study provide further data about the ability of quantitative studies of ultrasonic backscatter to identify alterations in the myocardium during injury.

Limited value of the resting electrocardiogram in assessing patients with recent onset chest pain: lessons from a chest pain clinic.

OBJECTIVE: To evaluate a clinic set up specifically to assess patients with recent onset chest pain, particularly those presenting with a normal resting electrocardiogram. DESIGN: Retrospective review of case notes. SETTING: Cardiac department of a tertiary referral cardiothoracic centre. PATIENTS: 250 consecutive patients with recent onset chest pain seen within 24 hours of general practitioner referral. OUTCOME MEASURES: Clinical diagnosis and management. RESULTS: 40% of patients were seen within seven days of the onset of symptoms. Twenty seven per cent had non-cardiac symptoms and could be discharged while 60% were considered to have cardiac pain. Sixty six patients (26%) were admitted directly from the clinic and 48 of these underwent coronary angiography within three weeks. Seventy patients (28%) have so far undergone intervention (angioplasty or coronary artery surgery), 22 within one month of presentation. One hundred and nine patients (44%) presented with a normal resting electrocardiogram, 21 of whom were considered to have unstable angina. Forty one of these patients were investigated of whom 37 were found to have significant coronary disease and 26 have undergone intervention. CONCLUSIONS: This experience highlights the inadequacy of a routine electrocardiogram reporting service in patients with recent onset of chest pain. An alternative facility offering immediate and complete cardiac assessment produced patient benefit with early diagnosis and intervention. Investigation of these patients, however, accounted for 5% of cardiac catheterisation laboratory throughput; this was a significant additional and unscheduled workload.

Relation between cyclic variation in echo amplitude and segmental contraction in normal and abnormal hearts.

OBJECTIVE: To study the relation between cardiac systolic activity and cardiac cycle dependent variation in the ultrasound signal arising from within the myocardium. DESIGN: Regional echo amplitude was used as a measure of the myocardial ultrasound signal. Relative echo amplitude values were assigned by standardising echo gain using the posterior parietal pericardium as an in-vivo calibration. M mode measurements of the left ventricle were used to assess cardiac systolic activity. Subjects were studied prospectively. Analysis of echo amplitude was performed by investigators who were blinded to the results of the M mode analysis. The influence of impaired left ventricular performance and abnormal wall motion were assessed. PATIENTS: 11 cardiomyopathy patients with impaired ventricular function, eight patients with severe pulmonary hypertension and reversed septal motion, and 19 healthy controls. SETTING: All subject studies were performed at Harefield Hospital. Echo amplitude analysis was performed at the Royal Brompton Hospital. MAIN OUTCOME MEASURES: Cyclic variation in echo amplitude was determined as the change in echo amplitude from end diastole to end systole. Additionally, an index of cyclic variation defined as the ratio of the cyclic change in echo amplitude to end diastolic echo amplitude was measured. Both cyclic variation and the cyclic variation index were analysed to see whether they correlated with left ventricular dimensions, fractional shortening, and systolic wall thickening. RESULTS: Stepwise regression analysis showed systolic wall thickening to be the most significant independent variable that correlated with the cyclic variation index for both the septum and posterior wall (r = 0.68, p = 0.0001, septum; r = 0.69, p = 0.0001, posterior wall). The slopes and intercepts for both regression equations were similar (y = 0.005x + 0.006, septum; y = 0.006x + 0, posterior wall). Subgroup analysis showed that the healthy controls, patients with cardiomyopathy, and patients with pulmonary hypertension had similar slopes and intercepts for their individual regression equations. CONCLUSIONS: These data support the hypothesis of a quantitative relation between the extent of cyclic variation of echo amplitude and the degree of segmental myocardial shortening, as measured by systolic wall thickening, which is not significantly influenced by location within the myocardium, left ventricular performance, or wall motion. They provide further evidence of the usefulness of quantitative analysis of myocardial echo amplitude in the study of regional myocardial function in both normal and injured myocardium.

Coronary reactivity to ergonovine--possible relationship to accelerated coronary arterial disease in cardiac transplant recipients.

Severe coronary artery spasm can occur in orthotopic cardiac transplant recipients. To investigate the possible mechanisms and relevance of coronary spasm to the subsequent development of coronary disease, the response of the coronary arteries to intracoronary ergonovine maleate was studied in 10 patients who had undergone orthotopic cardiac transplantation and were shown to have normal coronary arteries at angiography. Ergonovine in doses of 1, 5 and 10 micrograms was injected into the left coronary artery followed by 2 mg of isosorbide dinitrate. Proximal coronary artery luminal diameters were measured using automated computerized quantitative angiography of the left anterior descending (LAD) and circumflex (LCX) vessels. Five patients (responders) demonstrated a dose response curve to intracoronary ergonovine which was similar to that previously seen in non-transplant patients (mean percentage diameter change +/- SEM, -24.68 +/- 1.93 for LAD, -24.06 +/- 3.91 for LCX). The remaining five patients (non-responders) demonstrated a virtually flat dose response curve significantly different from that of the responders (P = 0.001 for LAD, P = 0.013 for LCX). Angiography after 2 years demonstrated significant coronary disease in four of the five responders to ergonovine. In contrast, the five non-responders to ergonovine continue to have no detectable disease by angiography.

Valvular regurgitation in heart-lung transplant recipients: a Doppler color flow study.

To assess the frequency and degree of valvular regurgitation in combined heart and lung transplant recipients, 50 patients were investigated using Doppler color flow echocardiography 20 to 909 days (mean 369) after heart-lung transplantation. The mean age (+/- SD) of the patients was 25 +/- 9 years. No patient had evidence of rejection at the time of the study. Fifty normal volunteers acted as control subjects. Tricuspid, mitral and pulmonary regurgitation were commonly observed in the patients undergoing heart-lung transplantation (78%, 52% and 68%, respectively), but were not significantly more frequent than in the normal subjects (68%, 42% and 70%, respectively). Aortic regurgitation was uncommon in both groups (4% and 2%, respectively). However, tricuspid and mitral regurgitant jet areas were significantly greater (p less than 0.01) in heart-lung transplant recipients than in normal subjects (156 +/- 120 and 84 +/- 52 mm2 compared with 40 +/- 38 and 28 +/- 26 mm2, respectively); pulmonary regurgitant jet area was not significantly different in the two groups (32 +/- 26 and 28 +/- 26 mm2, respectively). Regurgitant jet area was not significantly correlated with patient or donor age, donor organ total ischemic time, time after operation, use of steroids for immunosuppression or total number of rejection episodes. These results show that valvular regurgitation is not significantly more frequent after heart-lung transplantation than in normal subjects, but atrioventricular (AV) valve regurgitation, when present, is significantly greater in degree. This suggests that the degree but not the frequency of AV valve regurgitation is related to transplantation.

Continuous aortic regurgitation in severely dysfunctional native hearts after heterotopic cardiac transplantation.

Doppler techniques were used to investigate the frequency and characteristics of aortic regurgitation (AR) in the severely deteriorated native heart after heterotopic cardiac transplantation. Ten patients were studied in whom the native left ventricular fractional shortening was less than 6%. AR was detected by Doppler in 6 patients. The AR was continuous throughout the cardiac cycle in 3 patients, continuous when present (but not occurring with every beat) in 2 patients and present throughout diastole and continued into midsystole in the remaining patient. AR was associated with abnormalities of aortic valve opening (either its complete or intermittent absence) and with poor forward flow and even reversed flow through the native heart. It is postulated that AR in this group mainly occurs as a result of abnormal locking of the aortic valve due to severely impaired left ventricular ejection. Abnormal left ventricular diastolic function and enlargement may also be contributory.

Assessment of coronary angioplasty by an automated digital angiographic method.

Digital subtraction coronary angiograms (DSA) of 63 patients who had undergone coronary angioplasty (PTCA) for a total of 73 lesions were analyzed with an automated border-detecting computer program capable of simultaneous geometric and densitometric cross-sectional area estimation. The computer measurements were compared with visual interpretation of the 35 mm cineangiograms. The results indicated that visual reports of cineangiograms tend to overestimate the pre-PTCA diameter percent stenosis and to underestimate the post-PTCA residual stenosis in comparison with the computer (p less than 0.001 in bot cases). There was good agreement between geometric and densitometric area percent stenoses calculated by the program on the pre-PTCA digital angiograms (r = 0.82, p less than 0.001, mean of their differences = -0.2 with standard deviation = 6.1). Following PTCA, however, important discrepancies between the two methods existed (r = 0.71, p less than 0.001, mean of their differences = 1.0 with standard deviation = 18.6). Following PTCA (but not pre-PTCA), densitometric evaluation demonstrated a significantly greater mean coefficient of variation between different views (69%) than did the geometric evaluation on the same views (24%). We conclude (1) that visual interpretation of cine coronary angiograms compares poorly with quantitative methods for both the selection of PTCA candidates and the assessment of the results; (2) that the geometric and densitometric characteristics do not agree in describing the degree of post-PTCA residual stenosis; and (3) that after angioplasty, important discrepancies between densitometric evaluation in different views are observed.

Assessment of coronary angioplasty: comparison of visual assessment, hand-held caliper measurement and automated digital quantitation.

Digital subtraction coronary angiograms (DSA) of 27 patients who had undergone coronary angioplasty (PTCA) to a total of 32 lesions were analyzed using an automated border-detecting computer program and hand-held caliper measurement of diameter percent stenosis. The results were compared with visual interpretation of the 35-mm cineangiograms. Visual reports significantly overestimated the pre-PTCA diameter percent stenosis (P less than .001) and underestimated the residual post-PTCA narrowing compared with the automatic computer program (P less than .001). Caliper measurements overestimated significantly the pre-PTCA stenosis in comparison with the computer (P less than .01), but post-PTCA the two methods did not differ significantly (P = .105). There was a positive but poor correlation between caliper and computer measurements (r = .43, P less than .05) performed on the pre-PTCA digital angiograms. Post-PTCA the two methods correlated better (r = 0.78, P less than .001), but further statistical analysis showed important discrepancies between them. The correlation of visual reports and computer measurements was poor pre-PTCA (Kendall's tau = 0.32, P less than .05) and not statistically significant post-PTCA (tau = 0.64, P = .5). We conclude that there is observer bias in the visual reporting of angioplasty results, so that pre-PTCA lesions are overestimated, whereas post-PTCA are underestimated. Hand-held caliper measurement improves the assessment of coronary stenoses in comparison with the visual report but still may not altogether eliminate observer bias; it may overestimate the pre-PTCA stenoses compared with automated border detection.

A case of herpes zoster associated encephalitis treated with acyclovir.

The case of a 67 year old male who developed severe encephalitis associated with herpes zoster ophthalmicus is described. Encephalitis occurred in the absence of cutaneous dissemination and recovery followed treatment with Acyclovir.