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Aim: To analyse the clinical outcome and myocardial perfusion and function after transmyocardial revascularisation (TMR) in patients with normal left ventricular function and multivessel coronary artery disease non-amenable for standard revascularisation. Method and results: Twenty three severely symptomatic patients (CCS score median 4) with normal left ventricular systolic function but coronaries non-amenable for either PTCA or CABG were subjected to TMR. The angina score, left ventricular systolic and diastolic function in radionuclide ventriculography at rest, exercise tolerance and myocardial perfusion – Thallium-201 SPECT (adenosine stress 74 and 37 MBq under nitrate cover) were evaluated before and 3, 6, 12 months post-operatively. After an average of 40 ± 12 (range 14–56) TMR channels angina score decreased significantly (p< 0.0001) and the exercise tolerance increased (from 6.0 ± 4.5 to 9.1 ± 4.6 after 6 months, p< 0.05) in 21 patients. During the follow up period two patients had a myocardial infarction and one committed suicide after 6 months. Ejection fraction dropped significantly only after 1 year post-TMR from 70 ± 13 to 63 ± 0.13%, p < 0.05. The overall perfusion improved initially in 14 patients with subsequent deterioration in time. The changes in segmental perfusion were not associated with the symptomatic improvement. Conclusion: Transmyocardial revascularisation in patients with normal ejection fraction may improve the angina class, exercise tolerance and overall but not segmental perfusion and does not show any immediate effect on left ventricular function.

The percutaneous treatment of saphenous vein graft lesions containing angiographically massive thrombus is associated with a high risk of distal embolisation and no-reflow. The optimal management for these lesions remains unclear and a challenge to the interventional cardiologist. Five cases are described in whom the risks of percutaneous angioplasty were felt to be excessive owing to a high thrombus load. Each case was treated with a bolus and infusion of abciximab (ReoPro; Eli Lilly—a platelet glycoprotein IIb/IIIa receptor antagonist) at least 24 hours before further angiography. Repeat angiography of the culprit vein graft, following treatment with abciximab alone, demonstrated a major reduction in the thrombus score and the presence of TIMI 3 flow in each case. Immediately following repeat angiography, angioplasty with stent insertion was performed successfully with no distal embolisation or no-reflow phenomenon. This staged approach, with abciximab used alone to reduce thrombus load, is a new treatment for vein graft lesions containing massive thrombus. Keywords: thrombus; abciximab; glycoprotein IIb/IIIa receptor antagonists; interventional cardiology; angioplasty

Objectives. The concept of “cardioprotection” based on ejection fraction was tested to see whether patients with coronary artery disease in whom medical treatment fails to be cardioprotective can be distinguished from those in whom it is safe to continue such treatment. Background. Ejection fraction is of fundamental prognostic importance. Its modification by anti-ischemic medication may allow assessment of cardioprotection from adverse outcome. Methods. Exercise ejection fraction and the change in ejection fraction from rest to exercise were measured by radionuclide ventriculography with and without background medication in 102 mildly symptomatic patients with coronary artery disease suitable for revascularization but initially treated medically. Results. Over 20 months, 23 patients experienced an adverse event. With medication, exercise ejection fraction increased in patients with and without events. By contrast, the ejection fraction response to exercise improved significantly in the event-free group only; the group with events had a persistent decrease in ejection fraction. By Cox analysis, the ejection fraction response to exercise performed with medication made the most significant independent contribution to event-free survival. Comparison of areas under receiver operating characteristic curves suggested that this index is the most useful clinical measure of cardioprotection. Conclusions. An exercise-induced decrease in ejection fraction despite anti-ischemic medication implies failure of cardioprotection and a greater short-term risk of adverse outcome and crossover to revascularization in patients initially treated medically. Conversely, a preserved left ventricular performance confers a satisfactory prognosis while continuing with that treatment. Thus, the effect of medication on the ejection fraction response to exercise—a reasonable estimate of its cardioprotective efficacy—may influence the choice of continuing with such treatment or performing early revascularization.

We examined the prognostic value of exercise radionuclide ventriculography (RNV) performed on anti-ischaemic medication following thrombolysis. Within 3 months of thrombolysis for first myocardial infarction, 31 medically treated patients with revascularisable but non-critical and minimally symptomatic coronary disease had left ventricular ejection fraction (LVEF) measured by first-pass exercise RNV. This was first performed off treatment and then repeated within 4 weeks on patients' regular medication. Follow-up at 12 months post-thrombolysis showed that 5 patients (Group I) had suffered significant recurrent symptoms (worsening angina requiring revascularisation in 3, unstable angina in 1, reinfarction in 1), but 26 remained well (Group II). Both groups were similar in age, post-thrombolytic severity of coronary disease, exercise LVEF whether off (39% vs 43%) or on medication (43% vs 44%), and change in LVEF with exercise ([symbol: see text]LVEF) off medication (-11% vs - 3%). However, on medication, there was a significant difference in mean [symbol: see text]LVEF between Groups I and II (-11% vs + 5%, P = 0.0008, 99% confidence interval = 4 to 26%). Thus, following thrombolysis, an abnormal [symbol: see text]LVEF despite anti-ischaemic medication may identify patients at risk of significant early recurrent ischaemia. Post-thrombolysis prognostic testing by exercise RNV may therefore be of greater value when performed on rather than off medication.

During exercise radionuclide ventriculography, many patients with coronary artery disease exhibit painless myocardial ischemia defined as an abnormal left ventricular ejection fraction response without accompanying angina. To see if complete suppression of such exercise-induced painless ischemia by anti-ischemic medication implies a better prognosis in medically treated coronary artery disease, 34 patients underwent repeat testing at 4 weeks receiving regular conventional therapy that rendered angina no worse than class I. With such therapy, painless ischemia was abolished in 12 patients (group I) and persisted in 22 (65%, group II). Both groups were similar in age, number of diseased vessels, proportion with previous myocardial infarction, exercise ejection fraction, and degree of exercise-induced painless ischemia at baseline. At 9 months, adverse events had occurred in 11 patients (2 patients with myocardial infarction, 4 with unstable angina, 2 with angioplasty and 3 with bypass surgery). Only 1 of 12 patients (8%) in group I had experienced events compared with 10 of 22 (45%) in group II (chi-square, 5.4; p less than 0.025; 95% confidence interval, 12 to 61%). Thus, the relative risk of adverse events in patients whose painless ischemia was abolished was only 18% of that in patients in whom it was persistent. These results suggest that (1) the abolition of exercise-induced painless ischemia by conventional symptom-dictated medical therapy confers a better short-term prognosis in medically treated coronary artery disease, and (2) therapeutic efficacy may need to be assessed by titration against ischemia and not against angina.

To test the hypothesis that abolition of exercise-induced painless myocardial ischemia by antiischemic medication improves prognosis in patients with medically treated coronary artery disease, we studied such patients with painless ischemia during exercise radionuclide ventriculography performed after temporary discontinuation of medication. The test was repeated while patients received conventional medical therapy that rendered angina no worse than New York Heart Association class I. The relative risk of adverse cardiac events was reduced by >5-fold when painless ischemia was abolished by symptom-dictated therapy. Thus, the abolition of exercise-induced painless ischemia by conventional medical therapy carries a better short-term prognosis in medically treated coronary artery disease, suggesting that therapeutic efficacy may need to be assessed by titration against ischemia and not angina. In patients without overt cardiac events, there were no significant differences between baseline and 12-month measurements of ejection fraction at rest, peak exercise, and the change in ejection fraction from rest to exercise. Thus, in those who remain asymptomatic and event-free, painless ischemia that is easily inducible at baseline despite medication does not lead per se to deterioration of left ventricular systolic function at rest or during exercise over 12 months. Such an effect, if evident as early as at 12 months, would favor a strategy of early revascularization over medical treatment in asymptomatic patients who have inducible painless ischemia despite medication.

Percutaneous transluminal coronary angioplasty was attempted with elective percutaneous intra-aortic balloon pump support in 21 patients (mean age 60 years, range 40-82; 18 males) with unstable angina (n = 2), multivessel coronary disease requiring multivessel angioplasty (n = 2), severe left ventricular dysfunction (ejection fraction 10-30%; n = 16) or ventricular fibrillation at diagnostic angiography (n = 1). Fourteen patients had 3-vessel disease (1 with vein grafts also diseased), 6 had 2-vessel disease and 1 had isolated left anterior descending disease. Twenty-five procedures were performed (one in 18 patients, two in 2 patients and three in one patient) on 42 lesions in 34 vessels/grafts. There was no angioplasty-related death. Successful dilatation was achieved in 38/42 lesions (90%) in 21/25 procedures (84%) without major complication. Three procedures were complicated: one by major coronary dissection without sequelae, one by haemodynamic deterioration due to distal occlusion and one by an unstable residual stenosis in the attempted vessel necessitating urgent bypass surgery. The only complication related to the intra-aortic balloon pump was local haematoma in 2 patients. In conclusion, elective intra-aortic balloon pump support may be safely used to stabilise high-risk patients undergoing coronary angioplasty, leading to a satisfactory primary success rate.

Exercise radionuclide angiography appears to contribute additional prognostic information to catheterisation and clinical data. Probably, the most important predictor of all-cause cardiovascular mortality is exercise radio nuclide left ventricular ejection fraction. The prognostic value of exercise radionuclide ventriculography may be enhanced when performed on medical therapy, since an abnormal ejection fraction response to exercise despite antiischemic medications identifies the high-risk patient. For postthrombolytic patients the logistically optimum time for routine testing may be 6-8 weeks postinfarction and not much later to avoid missing the high-risk patient. In treated patients with silent ischemia, exercise radionuclide ventriculography may offer a simple means of individualizing and optimalizing such treatment.

An unusual complication of transvenous endocardial lead placement is reported in which an electrode became entrapped within the vicinity of the tricuspid valve apparatus, resisting all initial attempts at removal. The lead was subsequently successfully removed percutaneously via the right femoral vein.

We examined retrospectively the usefulness of routine clinic visits in preventing adverse cardiac events in 115 patients awaiting coronary surgery or angioplasty. Mean waiting time from angiography to revascularization was 126 days. A total of 126 visits were made by 80 patients. No deaths occurred, but one patient, despite three visits, suffered myocardial infarction at 316 days post-angiography. Eight patients required admission for unstable angina, five having been on the waiting list for less than 5 weeks. The mean number of clinic visits, number of diseased vessels and proportion on triple anti-ischaemic therapy were similar in the patients suffering such events and those remaining stable. In conclusion, the inherent unpredictability of coronary disease greatly limits the role of interim clinic visits in the prevention of adverse cardiac events in patients awaiting revascularization.

The adequacy of radioisotopic mixing in first-pass radionuclide studies of right ventricular function was assessed in 27 patients using multiple injections of gold-195m (half-life 30.5 sec). A theoretical disadvantage of the first-pass technique is inadequate mixing of the injected bolus with blood prior to entry into the right ventricle. Since the calculation of ejection fraction is based on the assumption of complete mixing, this would lead to errors. In order to assess the effects of bolus injection rates and bolus duration on the calculation of right ventricular ejection fraction, multiple, rapid, sequential studies were performed using gold-195m at four bolus injection rates (10, 5, 2 and 1 ml/sec). Slowing the injection rate caused a significant increase in bolus duration, and a significant increase in the number of cardiac cycles available for analysis. Mean ejection fraction, however, was not significantly changed. There was good correlation between right ventricular ejection fraction at all injection rates when compared to 10 ml/sec, and no injection rate led to a consistent over or underestimate of right ventricular ejection fraction. There was no significant relationship between change in bolus duration and variation in ejection fraction. These data indicate that mixing is adequate for first-pass studies of right ventricular function using a rapid bolus.

The relation of global and regional right and left ventricular function during the acute phase after a first myocardial infarction was assessed by first pass radionuclide angiography in 20 patients (10 after anterior and 10 after inferior myocardial infarction). The right ventricular ejection fraction did not differ significantly between the groups, but left ventricular ejection fraction was significantly depressed after anterior myocardial infarction. There was evidence of right ventricular dilatation and impaired transit in the group with inferior infarction. Five patients with anterior infarction and six with inferior infarction had abnormal right ventricular ejection fractions. Right ventricular wall motion abnormalities affected the septal wall in the group with anterior infarction and the free wall in the group with inferior infarction. The relation between right and left ventricular ejection fractions was markedly different in the two groups. In the group with anterior infarction there was a significant linear relation between right and left ventricular ejection fraction, whereas in the group with inferior infarction there was not. Thus right ventricular dysfunction commonly occurs after both anterior and inferior myocardial infarction. Right and left ventricular impairment are related after anterior myocardial infarction, but are independent after inferior myocardial infarction. Finally, the different effects of anterior and inferior myocardial infarction on right ventricular function may be explained by differences in septal and free wall involvement.

A 38-year-old women presented with an 11-year history of angina pectoris. Coronary arteriography disclosed a large right coronary artery which filled the entire left coronary tree retrogradely. The left main coronary artery ended blindly and was not connected to the aortic root. There were no atherosclerotic lesions in any vessel. Exercise thallium-20l scintigrams showed a perfusion defect in the anterior region of the left ventricle and exercise first pass radionuclide ventriculography showed anterior hypokinesis of the left ventricle with an ejection fraction of 54 per cent, compared with 60 per cent at rest. An aortocoronary saphenous vein graft was constructed to the left coronary artery. Four months after operation the patient is free from symptoms. Repeat thallium scintigrams were normal. Exercise radionuclide ventriculography after operation disclosed no wall motion abnormality, and ejection fraction on exercise was 70 per cent. The mechanism of angina in this patient is unclear but may have been related to the abnormal timing of delivery of blood to the left ventricular myocardium. Dual radionuclide stress testing showed abnormalities after operation. This non-invasive approach may be useful in the assessment of the physiological significance of coronary anomalies and of the value of corrective surgery.

The distribution of 201thallium (Tl) in the myocardium has been studied by the new technique of emission tomography, and compared with standard gamma camera images in 5 patients. Tomographic imaging was carried out using a dual-detector scanner operated under the single-photon technique. Initial results have been promising, with visualisation of resting perfusion defects in patients with recent infarction and those with ventricular aneurysms. Emission tomography has also been performed at exercise, and has shown tracer deficits in the distribution of significant coronary stenoses. This new approach to myocardial perfusion scintigraphy may lead to improved sensitivity for detecting apical and inferior wall abnormalities by providing depth information not available from a conventional two-dimensional image.

A prospective randomized trial was conducted to evaluate the effects of exercise-based cardiac rehabilitation after myocardial revascularization surgery (MRS) on work capacity (measured in mets) and left ventricular function as determined from ejection fraction (LVEF). Twenty-eight patients undergoing MRS were randomly assigned to experimental (aerobic exercise, n = 19) or control (muscle relaxation and low-level exercise, n = 9) groups. Patients were studied before surgery (T1) and 2 (T2), 8 (T3), and 24 (T4) weeks after surgery with first-pass radionuclide angiography both while they were at rest and during maximal upright cycle ergometric exercise. Subsets of patients were also studied at T2, T3, and T4 at a standard workload of 75 W, and during maximal exercise 1 year after surgery (T5). Work capacity improved in both groups although significantly more so in the experimental group (3.9, 3.8, 6.0, and 7.3 mets and 3.7, 3.7, 4.9, and 5.7 mets at T1, T2, T3, and T4 in the experimental and control groups, respectively). The differences between groups were significant by T3. Peak exercise LVEF increased significantly in both groups from T1 to T2 then decreased at T3 and remained unchanged through T5. Peak exercise LVEF at T3 to T5 remained significantly above that observed at T1. LVEF responses were not related to the exercise program. During a standard workload, heart rate decreased, blood pressure increased, and LVEF did not change in either group. After conclusion of the formal protocol (T4), work capacity and LVEF did not change for either group throughout an additional 6 months (T5).(ABSTRACT TRUNCATED AT 250 WORDS)

PTCA is a new technique for the treatment of certain patients with coronary artery disease. It involves dilatation of stenotic segments of artery using a balloon catheter, and is carried out in cardiac catheterization laboratories. If successful, the need for coronary bypass surgery may be removed, although some patients with initially successful PTCA will come to surgery eventually. Successful PTCA is associated with relief of angina, improved angiographic appearances and coronary perfusion. The primary success rate is between 65% and 80%, and the restenosis rate approximately 25%. 80% of patients will be angina free one year after PTCA. In this paper the indications, contraindications, technology, results and complications are discussed.

This paper describes the preparation and characteristics of a 195 m Hg 195 m Au generator for clinical use in first-pass radionuclide angiography of the heart. The generator has an efficiency of elution of 20–30% which is maintained over the whole of its useful life. Over 100 patients have taken part in clinical trials with the generator.

We conducted a retrospective study to correlate thrombotic variables with the risk from an acute coronary event, using a new in vitro technique, which measures haemostasis, thrombolysis and coagulation from non-anticoagulated blood samples. The analysis was based on data from 63 patients who had undergone exercise radionuclide ventriculography, 50 of whom were considered to be at risk from an acute coronary event because they satisfied at least one of the following three criteria: (1) coronary angiography documented disease, (2) prior myocardial infarction, (3) ventriculography assessed provocable ischaemia. Fifty matched normal subjects were used as controls. Significantly enhanced haemostasis was measured in patients considered at risk from acute coronary event, and haemostatic activity was further increased in patients with provocable ischaemia. Haemostasis in eight patients at risk (provocable ischaemia), who continued with the medication during the test, did not differ significantly from the controls. Greatly reduced spontaneous thrombolytic activity was measured in all patients at risk from acute coronary events. These findings suggest the presence of hyperactive platelets in patients at risk from acute coronary events, with an additional risk of greatly reduced spontaneous thrombolytic activity.

A 41-year-old man presented with dizziness associated with sinus bradycardia and sinus arrest. An attempt to implant a transvenous pacing lead was frustrated by absence of the right superior vena cava. The left superior vena cava persisted and drained via the coronary sinus into the right atrium. Absence of the right superior vena cava may present with symptomatic sinus node dysfunction and may require an epicardial demand pacing system.

Right ventricular rupture is rare. We report its identification by radionuclide ventriculography and subsequent confirmation by contrast angiography and at operation. The aetiology in this case was a primary cardiac malignancy.

Eighteen patients with a history of previous anterior myocardial infarction and suspected left ventricular aneurysms were studied both by contrast left ventriculography and by first pass radionuclide ventriculography using Technetium99m and a computerised multicrystal gamma camera. The radionuclide study successfully identified all 14 patients with aneurysms and all 4 with diffusely hypo-kinetic ventricles. Ejection fraction calculated from the change in radioactive counts in the left ventricle correlated well with that calculated from the area-length method from the contrast angiogram (r = 0.83). Ventricular volumes calculated from the area-length formula for both contrast and radionuclide angiograms correlated closely (r = 0.85 and r = 0.89 for end-systolic and end-diastolic volumes, respectively). In the patients with aneurysms, there was a close correlation between the extent of akinesis, as assessed by the two methods (r = 0.94). The ability of the radionuclide ventriculogram to provide accurate information on global and segmental ventricular function, and to differentiate between segmental and diffuse ventricular dysfunction, enables the method to act as a screening procedure in the investigation of patients with suspected left ventricular aneurysms.

Mycotic aneurysms are a rare but recognized complication of infective endocarditis. Aneurysms of the pulmonary artery are usually associated with infected congenital heart lesions and especially with persistent ductus arteriosus. This report deals with a patient with a persistent ductus who developed multiple mycotic aneurysms in the right lung following infective endocarditis, and whose management was complicated by anomalous venous drainage of most of the contralacteral lung. Surgical closure of the ductus to reduce pulmonary blood flow failed to prevent haemoptysis, and further surgery to ligate the feeder arteries to the aneurysms was required.

Sudden strenuous exercise (SSE) has been shown to produce ischemic electrocardiographic (ECG) responses, abnormalities of myocardial blood flow, and decreases in left ventricular ejection fraction. Prior exercise taken as warm-up has been shown to ameliorate the ECG and myocardial blood flow abnormalities induced by SSE. The purpose of this study was to determine whether warm-up would normalize the responses of the left ventricular ejection fraction to SSE. Twenty healthy male volunteers performed SSE (400-W bicycle exercise) either with (group A, n = 10) or without (group B, n = 10) warm-up. Ejection fraction was measured using first-pass radionuclide angiography under control conditions and during SSE. During SSE ejection fraction decreased from control values in both group A (70.5 +/- 6.3 to 64.8 +/- 8.2%) and group B (70.3 +/- 10.1 to 57.7 +/- 7.7%), although ejection fraction was significantly higher during SSE in group A. The results are consistent with the hypothesis that the abnormal responses to SSE are attributable to subendocardial ischemia secondary to a delay in autoregulation of myocardial blood flow. However, the decrease in ejection fraction during SSE even following warm-up suggests that the mechanism for the abnormal response to SSE is more complicated than previously hypothesized.

Respiratory effort during inspiration, expiration, and the Valsalva manoeuvre changes right ventricular preload and afterload. On inspiration these changes should improve systolic emptying of a larger end diastolic volume and so increase the ejection fraction, whereas on expiration the reverse should be true. The resting right ventricular ejection fraction was measured by first pass radionuclide angiography with gold-195m (half life 30.5 s) in 17 individuals at maximal inspiration and expiration and in eight at rest and during the strain phase (phase 2) of the Valsalva manoeuvre. The right ventricular ejection fraction was significantly lower during expiration than during inspiration. There were, however, no significant differences in bolus duration or right ventricular transit time. The Valsalva manoeuvre, in contrast, significantly increased the ejection fraction and also significantly prolonged both the bolus duration and right ventricular transit time. The conformation of the bolus curves during the Valsalva manoeuvre suggested the development of tricuspid regurgitation. These data suggest that relative influences of venous return, pulmonary arterial pressure, pulmonary vascular resistance, and possible functional tricuspid regurgitation vary during inspiration, expiration, and the Valsalva manoeuvre and can affect the right ventricular ejection fraction. Changes in right ventricular function on exercise assessed by first pass radionuclide angiography must be interpreted with caution because maximal respiratory effort may alter the right ventricular ejection fraction independently of ischaemia or other non-ischaemic factors.

With technetium-99m radiopharmaceuticals, first pass radionuclide angiocardiography is of limited use for multiple intervention studies because of the large radiation burden imposed on the patients. A portable mercury-195m/gold-195m generator has been developed capable of producing 17 to 20 mCi aliquots of the short half-life (30.5 seconds) gold-195m in less than 0.5 ml of generator eluate. Safety of the eluate has been established both in the experimental animal and in human beings. Fifteen patients underwent two first pass radionuclide angiograms with gold-195m, followed by a standard technetium-99m study. There was a close correlation between the left ventricular ejection fraction measured from gold and technetium studies (correlation coefficient [r] = 0.99, standard error of the estimate [SEE] 3.1%). Interobserver and sequential reproducibility of gold studies were excellent (mean variability ± standard deviation [SD]2.0 ± 2.9 and 0.6 ± 2.7%, respectively). Statistical reliability of the gold studies, as assessed from the observed left ventricular end-diastolic counts, matched that of technetium studies, and similarly, the images obtained from the two radiopharmaceuticals were identical. Residual count rates 5 minutes after first pass acquisition with gold were 480 ± 140 counts/s in the whole field of view, and 50 ± 30 counts/s over the left ventricle, these values being less than 1% of the residual counts after technetium. Accurate, reproducible, high count-rate first pass studies are obtainable with gold-195m, with a markedly reduced radiation exposure to the patients. It is now possible to perform rapid sequential first pass cardiac imaging studies without the constraints of an unacceptable high radiation burden.

The perfect image is one that is indistinguishable from the original object under the same viewing conditions. Unfortunately, there is no nuclear medicine image that meets this criterion, and interpretation of cardiac scintigrams is hampered by the limited resolution of our imaging systems, compounded by the fact that unlike other organs the heart moves while being imaged. Nevertheless, with careful attention to technical detail and by employing rigorous standards for the three major facets of nuclear cardiology, namely, acquisition, analysis and interpretation of data, the very imperfect nuclear cardiology images can be of major clinical value. The requirements for these facets vary greatly, from the simple gamma camera equipped with a persistence oscilloscope and a polaroid camera for qualitative interpretation of analogue thallium scans, to highly sophisticated camera-computer systems for quantitative analysis of static or dynamic data.

Non-traumatic hemothorax is rare and in the case we report was due to rupture of a benign thymoma. The clinical course of the patient suggested rapid intrathoracic bleeding and emergency surgery was required to make the correct diagnosis.

There is no consensus as to the best projection or correction method for first-pass radionuclide studies of the right ventricle. We assessed the effects of two commonly used projections, 30° right anterior oblique and anterior-posterior, on the calculation of right ventricular ejection fraction. In addition two background correction methods, planar background correction to account for scatter, and right atrial correction to account for right atrio-ventricular overlap were assessed. Two first-pass radionuclide angiograms were performed in 19 subjects, one in each projection, using gold-195m (half-life 30.5 seconds), and each study was analysed using the two methods of correction. Right ventricular ejection fraction was highest using the right anterior oblique projection with right atrial correction 35.6 ± 12.5% (mean ± SD), and lowest when using the anterior posterior projection with planar background correction 26.2 ± 11% (p

Twelve patients were studied by rest and exercise radionuclide ventriculography following left ventricular aneurysmectomy (LVA). Left ventricular filling pressure (LVFP) was also measured. Nine patients had been studied pre-LVA at rest and exercise before and after isosorbide dinitrate (ISDN). Resting ejection fraction (LVEF) improved after LVA (p less than 0.25), but exercise LVEF did not. End-diastolic volume (EDV) and resting LVFP also fell after LVA (p less than 0.25 for EDV, p less than 0.05 for LVFP) and although exercise LVFP fell (p less than 0.02), the values were abnormal in all patients. Ejection fraction of contractile segment (EFCS) from the resting radionuclide study pre-LVA was related to resting LVEF post-LVA (r = 0.71 p less than 0.02), although postoperative LVEF could not be predicted from preoperative EFCS in individual patients. Deterioration in LVEF and LVFP from rest to exercise post-LVA occurred both in patients with single-vessel occlusion and in those with multivessel coronary disease, irrespective of whether or not revascularization had been performed. Thus LVA is effective in improving resting ventricular function; exercise performance may remain abnormal even in patients without residual coronary disease.

Serial changes in left ventricular function on exercise were assessed by first pass radionuclide angiography with gold-195m (half life 30.5 s) in 25 men with known coronary anatomy. In the seven patients with three vessel disease, abnormalities of global left ventricular function and regional wall motion occurred earlier during exercise, were of greater extent at peak exercise, and persisted longer after exercise than in the 11 patients with one and two vessel disease or the seven with normal coronary arteries. Although there were significant differences between the groups in absolute change in ejection fraction and the rate of change in ejection fraction related to exercise duration and heart rate, a considerable overlap of values between groups precluded the accurate prediction of coronary anatomy in individuals. These data suggest that the amount of myocardium at risk from ischaemia in some patients with one and two vessel disease may resemble that in patients with three vessel disease. This study shows that an anatomical classification based solely on the number of diseased vessels will not predict the extent of the impairment of left ventricular function on exercise.