Assessment of function of contractile segments in patients with left ventricular aneurysms by quantitative first pass radionuclide ventriculography. Haemodynamic correlation at rest and exercise

Computed tomographic assessment of left ventricular aneurysms

Twenty patients with left ventricular aneurysms were studied by left ventricular angiography and computed tomography. Measurements of left ventricular short axis, percentage of non-aneurysmal myocardium, and size of aneurysm were determined by both techniques. Qualitative assessments of left ventricular size together with the anatomical relation of the aneurysm to the ventricle were also made. The aneurysm was assessed for resectability by both techniques using these criteria. In all cases there was a distinct and diagnostic change in the contour of the ventricle on computed tomography. Computed tomography indicated eight aneurysms to be unresectable, and this agreed with the angiographic assessment. Of the remaining 12 aneurysms, seven were considered to be resectable on angiography. Computed tomography appears to be a reliable non-invasive technique for identifying left ventricular aneurysms and a useful screening method for identifying unresectable aneurysms.

Peak exercise and immediate postexercise imaging for the detection of left ventricular functional abnormalities in coronary artery disease

Eleven patients without significant coronary artery disease (CAD) (group A), 22 patients with significant CAD and no prior myocardial infarction (MI) (group B), and 10 patients with CAD and a previous MI (group C) were imaged at rest, at peak exercise and immediately after exercise by first-pass radionuclide angiography. At peak exercise, mean left ventricular (LV) ejection fraction (EF) did not change significantly in group A or C and decreased significantly in group B. However, in all groups mean LVEF increased significantly immediately after exercise. Examination of potential criteria for an abnormal LVEF response showed that changes from rest to peak exercise were sensitive for detection of CAD but were not specific. Postexercise criteria were more specific but relatively insensitive: 15 of 32 patients (47%) with CAD showed a normal (greater than 5% increase over rest) response after exercise. Similarly, a regional abnormality at peak exercise was 100% sensitive, compared with a sensitivity of 78% after exercise for the whole group, and only 68% in patients without prior MI. Seven patients would have been misclassified as normal if postexercise imaging alone had been performed. The likelihood of an abnormal postexercise EF response was related to the extent of CAD: No patient with 1-vessel, 8 of 17 with 2-vessel and 9 of 12 with 3-vessel CAD showed such a response. Peak exercise imaging is necessary to achieve maximal sensitivity for the detection of CAD, and a high false-negative rate will be obtained if postexercise imaging only is used. The combination of peak exercise and postexercise imaging may be of value in assessing the severity of CAD.

Combined exercise radionuclide and hemodynamic evaluation of left ventricular aneurysmectomy

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.

Phasic abnormalities of left ventricular emptying in coronary artery disease

Seventy subjects with suspected coronary artery disease were studied by radionuclide angiocardiography. Delayed or paradoxically emptying regions of the left ventricle were detected by a relatively new nuclear technique--phase imaging. The results were assessed in the light of cardiac catheterisation findings. Compared with 19 normals, regions with abnormally high phase (and therefore late emptying) were found in 42 of 61 subjects with coronary disease. High phase values were associated with total occlusion of a major coronary artery, low ejection fraction, and extensive wall motion abnormalities. The phase image greatly facilitated the calculation of contractile segment ejection fraction in 14 cases of left ventricular aneurysm. In three of these postoperative left ventricular ejection fraction agreed closely with preoperative contractile segment ejection fraction and there was a distinct improvement in the phase image after aneurysmectomy.