Myocardial thallium-201 scintigraphy for assessment of viability in patients with severe left ventricular dysfunction.

Many patients with ischemic heart disease and depressed left ventricular (LV) function have asynergic zones with sustained microcirculatory perfusion and myocardial metabolic activity that exhibit improved systolic function after coronary revascularization. The 2 predominant noninvasive techniques used to determine myocardial viability in patients with severely depressed LV function are thallium-201 (201Tl) scintigraphy and positron emission tomography (PET). Myocardial extraction of 201Tl is unaltered under experimental conditions of myocardial stunning or short-term hibernation (characterized by decreased flow and ischemic dysfunction). Akinetic or dyskinetic LV wall segments can exhibit normal or near normal 201Tl uptake as long as some residual flow is present. 201Tl scintigraphy can identify viable asynergic segments when performed on patients with severe coronary artery disease who are in the resting state. Many of these patients have initial resting defects that demonstrate delayed redistribution, or mild persistent defects that show improved perfusion and function after revascularization. There is a direct correlation between the extent of 201Tl uptake in zones of severe regional myocardial asynergy and the magnitude of improvement in resting LV ejection fraction after coronary bypass surgery. Rest 201Tl scintigraphy may help in the selection of patients with coronary artery disease and severely depressed LV function who would benefit the most from revascularization.     

Degos' disease with constrictive pericarditis: a case report

A 47-year-old man with Degos' disease was examined by echocardiography, which showed hypokinesis of the apical left ventricular wall with pericardial effusion. To evaluate the myocardial perfusion and coronary flow reserve, 201Tl scintigraphy and intracoronary Doppler flowmetry were performed. The coronary flow reserve was not decreased nor was there angiographical coronary stenosis, although a pressure study revealed constrictive dysfunction of both ventricles. The constrictive pericarditis might have been induced by pericardial vasculitis, thereby causing the left ventricular wall motion abnormality.     

Myocardial viability in patients with Q wave myocardial infarction and no residual ischemia.

BACKGROUND. Coronary revascularization in patients with persistent angina after myocardial infarction reduces the incidence of recurrent angina pectoris and myocardial infarction and improves left ventricular function. The results of revascularization after a Q wave myocardial infarction when there is no residual ischemia may depend on myocardial viability. METHODS AND RESULTS. To determine whether there was viable myocardium in the infarct area in the absence of clinical and scintigraphic evidence of myocardial ischemia, 15 asymptomatic patients with a Q wave myocardial infarction, no redistribution on stress 201Tl test, and single-vessel disease (greater than 70% stenosis) with persistent anterograde blood flow were randomized to percutaneous transluminal coronary artery angioplasty (PTCA) or conservative medical treatment. After 2 months of follow-up, mean coronary blood flow measured by Doppler catheter in the infarct-related artery was higher in the PTCA treatment group (33 +/- 6 ml/min, n = 8) than in the conservative treatment group (16 +/- 4 ml/min, n = 7; p less than 0.05 between groups). The 201Tl pathological-to-normal ratios measured on postexercise images did not change in patients treated conservatively during the follow-up period (delta = +1.1 +/- 2.2%; NS from baseline) but increased significantly in patients treated by PTCA (delta = +8.5 +/- 2.3%; p less than 0.01 from baseline; p less than 0.05 between groups). Segmental wall motion improved on left ventricular angiography 2 months after PTCA (delta = +11.5 +/- 2.2%; p less than 0.001 from baseline) significantly more than in the conservative treatment group (delta = +4.1 +/- 1.4%; p less than 0.05 between both groups). Improvements of 201Tl ratios and segmental wall motion indexes correlated significantly (r = 0.73, p = 0.002). The mild improvement of global left ventricular ejection fraction measured in the PTCA treatment group did not differ significantly from changes in the conservative treatment group. CONCLUSIONS. Successful angioplasty of the stenotic infarct artery in patients with a Q wave myocardial infarction and no residual ischemia improved coronary flow, 201Tl uptake in the infarct area, and regional wall motion. Therefore, myocardial viability may last several weeks, as long as residual blood flow persists in the infarct-related artery. Optimal assessment of viability by imaging techniques should identify patients who are most likely to benefit from revascularization.     

Exercise left ventricular performance in patients with mitral valve prolapse

Patients with mitral valve prolapse may, even in the absence of associated coronary artery disease or significant mitral regurgitation, have abnormality in exercise left ventricular function. The precise reason for this abnormality, which appears to be age and sex related, is not clear. Abnormal ejection fraction response to exercise cannot be predicted by the nature of symptoms, electrocardiographic changes, arrhythmias, or by extent and severity of mitral valve prolapse by echocardiography. Caution should therefore be exercised in diagnosing associated coronary artery disease based on the ejection fraction response to exercise per se or even on exercise-induced wall motion abnormality. Patients with prolapse, have reduced exercise tolerance, which has been ascribed to reduced left ventricular filling and smaller left ventricular end-diastolic volume in the upright position. Patients with mitral valve prolapse and associated coronary artery disease or significant mitral regurgitation often have, as expected, abnormal left ventricular function during exercise.     

Comparison between dobutamine echocardiography and thallium-201 scintigraphy in detecting residual stenosis,ischemia, and necrosis in patients with prior myocardial infarction

Background: Following the first attempts to detect myocardial ischemia with two-dimensional echocardiography stress testing, pharmacologic stress using dobutamine infusion has become an alternative to echocardiography exercise testing for evaluation of coronary artery disease. It has been shown that stress echocardiography has a diagnostic accuracy similar to that of an exercise thallium test. Other studies, however, indicated that radionuclide myocardial perfusion imaging was more sensitive than exercise or pharmacologic stress echocardiography for detection of ischemia or jeopardized myocardium. Hypothesis: The aim of the present study was to determine the ability of dobutamine stress echocardiography in comparison with thallium-201 scintigraphy to identify multivessel disease and the presence of myocardial scar and ischemia in 60 consecutive patients who suffered a first myocardial infarction (MI). Methods: Patients were evaluated by coronary angiography and ventriculography, thallium-201 (²⁰¹Tl) tomographic scintigraphy, and dobutamine echocardiography within 3 months of a first MI. Forty-seven had Q-wave MI and 13 had non-Q-wave MI. Eleven patients were excluded from final analysis—7 because of failure to achieve target heart rate in spite of the use of atropine, and 4 because of high blood pressure following the infusion of dobutamine. Results: Dobutamine echocardiography showed an overall sensitivity of 43% for detection of coronary artery lesions of 50–74% diameter stenosis and ²⁰¹Tl scintigraphy showed a sensitivity of 71%. For detection of lesions of ≥75% diameter stenosis, dobutamine echocardiography showed a sensitivity of 52% and ²⁰¹Tl a sensitivity of 70%. Overall agreement between wall motion and myocardial perfusion for detection of necrosis and/or ischemia in the infarct area was 40.4% with a kappa coefficient of 0.09 (p = 0.13). For detection of ischemic myocardium outside the infarct zone, overall agreement was 78.6% with a kappa coefficient of 0.49 (p<0.0001). Conclusion: Dobutamine echocardiography results showed a lower sensitivity than myocardial perfusion images in predicting multivessel coronary artery disease, and there was poor agreement between both methods in identifying necrosis or ischemia.     

Tl-201 perfusion scintigraphy of the myocardium in patients with anomalous origin of the left coronary artery from the pulmonary trunk (clinico-anatomical comparisons)

The clinical significance of 201Tl myocardial perfusion scintigraphy was studied in 7 patients with abnormal branch of the left coronary artery from the pulmonary trunk and in 1 patient with that of the anterior interventricular artery from the pulmonary trunk. Radiological criteria for the defect were established on the basis of comparative analysis of the data of myocardial scintigraphy with those of electrocardiographic, coronary angiography and anatomic examinations. It was shown that it was feasible to make a differential diagnosis between abnormal left coronary artery branch and dilated cardiomyopathy and that the technique was of value for comparative assessment of the efficacy of various types of surgical treatment for abnormal left coronary artery ramus from the pulmonary trunk.     

Transient predominant right ventricular ischemia caused by coronary vasospasm

This study describes the clinical experience with four patients with variant angina caused by spasm of the right coronary artery who were assessed for evidence of right ventricular involvement. The patients were suspected of having predominant right ventricular ischemia on the basis of normal thallium-201 scans, left ventricular ejection fraction, regional wall motion assessed by equilibrium radionuclide angiography (RNA), two-dimensional echocardiographic findings, and left ventricular hemodynamics; all procedures were performed during transient ST segment elevation in the inferior leads. Right ventricular ischemia was documented in four patients by first-pass radionuclide studies and phase analysis of RNA, and in three patients by simultaneous right and left hemodynamic monitoring. The clinical findings from these four patients are compared with those from four other patients with similar electrocardiographic changes, coronary anatomic distribution, and documented right coronary spasm but with evidence of left ventricular involvement as documented by abnormal thallium-201 scintigraphy, RNA, two-dimensional echocardiography, and left hemodynamics during ischemic episodes. Although preliminary, these data indicate the existence of prevalent right ventricular ischemia during variant angina caused by right coronary vasospasm. This condition should be suspected whenever typical anginal symptoms and/or ischemic electrocardiographic changes are accompanied by normal thallium-201 scintigraphic findings and/or normal left ventricular function as assessed by RNA, echocardiography, and left hemodynamic monitoring. Among noninvasive procedures, first-pass radionuclide study and phase analysis of RNA represent suitable techniques for detecting transient right ventricular dysfunction.     

Submaximal exercise testing after acute myocardial infarction: myocardial scintigraphic and electrocardiographic observations.

The relation between global and regional left ventricular function and electrocardiographic signs of ischemia at rest and during submaximal supine exercise was studied in 27 patients 2 to 3 weeks after acute myocardial infarction. Dynamic myocardial scintigraphy was performed at rest and during submaximal exercise utilizing an in vivo method of labeling red blood cells with technetium-99m pertechnetate. Gated radionuclide blood pool scintigrams were obtained in a modified left anterior oblique, and in some patients also in the right anterior oblique projection, to measure left ventricular ejection fraction and segmental wall motion. Electrocardiographic monitoring of heart rate and rhythm was provided during the exercise. The submaximal exercise test was terminated when the patient's heart rate reached 125 beats/min or if angina, malignant ventricular ectopy or electrocardiographic evidence of myocardial ischemia developed before this rate was reached. The data demonstrate that patients with a recent anterior myocardial infarct, in contrast to patients with a recent inferior or nontransmural infarct, manifest a significant reduction in left ventricular ejection fraction with submaximal exercise. Of the eight patients with an anterior infarct, seven had segmental wall motion abnormalities at rest. Four of these eight manifested more severe abnormalities with submaximal exercise; three had abnormalities at rest that did not change with exercise. Four of the eight had a positive electrocardiographic response during exercise (two were taking digoxin). Of these four, only two had more marked wall motion abnormalities with effort. Of the 13 patients with an inferior infarct, 11 had apparently normal wall motion in the modified left anterior oblique projection at rest, including 2 who manifested segmental wall motion abnormalities with submaximal exercise; the 2 remaining patients had wall motion abnormalities at rest that, on exercise, became more marked in one and were unchanged in one. Four of the 13 had a positive electrocardiographic response with exercise (one was taking digoxin); only one of these had a detectably more severe wall motion abnormality with exercise. Of the six patients with a nontransmural infarct, four had no identifiable wall motion abnormalities at rest; in one of these, an abnormality developed with exercise. The remaining two patients had wall motion abnormalities at rest; in one, a positive electrocardiographic ischemic response developed with exercise. Patients with an anterior infarct appear to have a different functional ventricular response to submaximal exercise at the time of hospital discharge than patients with an inferior or nontransmural infarct. To identify ischemic responses with submaximal exercise in these patients one should ideally use both electrocardiographic monitoring and dynamic myocardial scintigraphy.     

Noninvasive assessment of T-wave abnormalities on precordial electrocardiograms in middle-aged professional bicyclists

Six middle-aged, active, professional bicyclists with T-wave abnormalities on precordial ECGs were studied noninvasively. Twenty-five age-matched bicyclists without T-wave abnormalities served as the control subjects.Increased voltage of SV1 + RV5 was demonstrated in all subjects. A 5-year follow-up study revealed that these abnormalities of T-wave inversion became more pronounced with age, except in one case. VCGs showed enlargement of anterior QRS loop and discordant T loop, in all cases. On echocardiography, thickness of both the interventricular septum and the left ventricular posterior wall, and left ventricular mass were significantly increased compared with the control group. ²⁰¹Tl myocardial scintigraphy at rest and during exercise revealed no regional perfusion defects of the tracer in either case.We conclude that: (1) T-wave abnormalities of precordial ECGs in six middle-aged athletes were progressive in nature; and (2) these electrocardiographic abnormalities seem to be related to left ventricular hypertrophy induced by steady and strenuous training rather than to coronary artery disease.     

Anterior left ventricular wall echoes in coronary artery disease. Linear scanning with a single element transducer

The feasibility and usefulness of obtaining anterior left ventricular wall echoes were studied using a linear cardiac scan with a single element tranducer and M mode recordings. One hundred four patients were examined: 50 with acute myocardial infarction and 54 who underwent left ventricular angiography and coronary cineangiography for evaluation of chest pain. Of the 54 patients with cardiac catheterization studies, 11 had no evidence of cardiac disease, 42 had 50 percent or greater obstruction in one or more of the three major coronary arteries and one had aortic insufficiency. Anterior left ventricular wall echo motion toward the transducer or absence of motion during ejection was called abnormal, and motion away from the transducer during ejection was interpreted as normal. Abnormal motion was seen in four of four patients with an isolated lesion of the anterior descending coronary artery, in one of three with an isolated lesion of the right coronary artery and in neither of two with an isolated lesion of the left circumflex artery. Of the 20 patients with obstructive coronary artery disease by arteriography and abnormal left ventricular wall echo motion, 18 had obstruction of the left anterior descending artery with or without other disease. Correlation of the anterior left ventricular echograms with the left ventricular angiograms was poor, with agreement in only 66 percent (33 of 50) of cases. Twenty-five of 26 patients with acute infarction and abnormal anterior left ventricular wall echo motion had electrocardiographic changes indicative of anterior or lateral wall infarction, or both. Twenty-five of 34 patients with electrocardiographic changes indicative of anterior wall infarction had an abnormal anterior wall motion echo. This study shows that obtaining the anterior left ventricular wall echo is feasible and useful in patients with coronary artery disease since abnormal anterior left ventricular wall motion is closely associated with anterior wall ischemia or infarction in these patients.     

Nitroglycerin-induced heterogeneous subendocardial myocardial blood flow observed by cardioscopy in patients with coronary artery disease

It is controversial as to whether or not nitroglycerin (NTG) increases subendocardial myocardial blood flow (SMBF), and if it does, whether arterial or venous blood flow is increased in patients with coronary artery disease. This study was performed to examine NTG-induced changes in SMBF.Changes in SMBF induced by NTG (200 μg, i.v.) were examined by cardioscopy in 58 left ventricular wall segments of 58 patients with coronary artery disease. NTG-induced red and purple endocardial colors were defined as increased arterial and venous SMBF, respectively. Endocardial color before NTG administration was classified into brown, light brown, pale and white. Endomyocardial biopsy of the observed portion and (201)Tl scintigraphy were performed in 40 of these patients immediately after cardioscopy and several days after cardioscopy, respectively.Upon administration of NTG, SMBF increased in 48 of 58 wall segments; arterial SMBF in 34 and venous SMBF in 12 wall segments; arterial SMBF in all 24 brown to light brown segments; venous SMBF, arterial SMBF and no change in 12, 10 and 5 of pale segments, respectively; and no change in all 10 white wall segments. (201)Tl-scintigraphy and endomyocardial biopsy revealed that brown, light brown, pale and white endocardial color represented no ischemia, mild ischemia, severe ischemia and fibrosis, respectively.NTG caused an increase in either arterial or venous SMBF depending on control endocardial color, wall motion and severity of coronary stenosis.     

'Tako-Tsubo cardiomyopathy' associated with syndrome malin: reversible left ventricular dysfunction.

A 66-year-old man developed a fever and had a syncopal attack during treatment with imipramine and amantadine for depression and Parkinson's disease. His muscular enzyme levels were very high, so he was diagnosed with incomplete syndrome malin and given hydration therapy. The electrocardiogram recorded an ST segment elevation like acute myocardial infarction in most leads, and the echocardiogram revealed left ventricular dysfunction with severe hypokinesis to dyskinesis of the anterior and apical wall regions, and hyperkinesis of the basal wall. One month from onset, the left ventricular contractility had not changed despite normal coronary arteries. Thallium-201((201)Tl) myocardial scintigraphy showed a perfusion defect and there was no accumulation of iodine-123((123)I) metaiodobenzylguanidine (MIBG) in the entire apex of the heart. Left ventricular function returned to normal and repeat (201)Tl scintigraphy showed recovery by the 4th month. However, there was still an absence of cardiac MIBG uptake. There are a number of reports from Japan of a syndrome demonstrating such reversible left ventricular dysfunction, called 'tako-tsubo cardiomyopathy', but the present case is the first to be associated with syndrome malin. A coronary microvascular abnormality and cardiac sympathetic denervation probably both play an important role in tako-tsubo cardiomyopathy.     

Scintigraphic anatomy of coronary artery disease in digital thallium-201 myocardial images.

One hundred and eight patients with single and multiple vessel coronary artery disease confirmed by arteriography were evaluated by exercise thallium-201 (201Tl) myocardial scintigraphy to determine the scintigraphic appearances of specific coronary stenoses. In general proximal stenoses caused more widespread, but not necessarily more severe, myocardial tracer deficit than distal stenoses. In particular, proximal dominant right coronary artery disease was specifically associated with extensive inferior wall tracer deficit in the anterior scintigram, whereas proximal left circumflex disease caused similar tracer depletion best visualised in the left lateral scintigram. A triad of uptake defects was caused by left anterior descending coronary artery disease: viz. apical tracer deficit (anterior view) in 71% lesions, septal tracer deficit (left anterior oblique view) in 83% of lesions, and anterolateral wall tracer deficit (left lateral projection) in 72% of lesions. The last defect has been termed a 'diagonal window' because it was associated with independent disease of the main diagonal branch of the left anterior descending coronary artery or with disease in the main left anterior descending artery situated proximal to this branch. Diagonal window tracer deficit was the most useful scintigraphic sign distinguishing proximal from distal disease in the left anterior descending coronary artery. False negative scintigraphic defects occurred more commonly in patients with triple vessel disease and in association with well-developed coronary collateral vessels. Certain scintigraphic patterns of 201Tl myocardial accumulation appear invaluable in the noninvasive localisation of stenoses within specific coronary arteries and thus may be useful in predicting life-threatening coronary artery disease which should be confirmed by definite coronary arteriography. The digital 201Tl myocardial scintigram also provides an independent functional guide to the interpretation of coronary arteriograms and may be helpful in the planning of aortocoronary bypass graft surgery.     

Assessment of left ventricular performance and myocardial viability using quantitative radioisotope techniques.

The diagnostic value of a combined radionuclide technique was compared with conventional angiocardiographic techniques in 60 patients with coronary artery disease. Quantitative 201Tl myocardial imaging combined with radionuclide angiocardiography using 99mTc-HSA provided a safe and accurate method for the assessment of left ventricular performance. The defects on the 201Tl images correlated with the severity of asynergy seen on the contrast ventriculogram. Static imaging alone distinguished hypokinetic from akinetic or dyskinetic areas. However, using both tracer techniques, akinesis could bedistinguished from dyskinesis. In patients with disturbed left ventricular function, cardiac transit times correlated with haemodynamic changes, and left ventricular ejection fraction was the most sensitive index. Thus, this combined radionuclide approach provides data for the evaluation of overall and regional wall function. A major advantage of this non-invasive auantitative technique is its applicability to the critically ill patient at the bedside.     

Assessment of left ventricular performance and myocardial viability using quantitative radioisotope techniques.

The diagnostic value of a combined radionuclide technique was compared with conventional angiocardiographic techniques in 60 patients with coronary artery disease. Quantitative 201Tl myocardial imaging combined with radionuclide angiocardiography using 99mTc-HSA provided a safe and accurate method for the assessment of left ventricular performance. The defects on the 201Tl images correlated with the severity of asynergy seen on the contrast ventriculogram. Static imaging alone distinguished hypokinetic from akinetic or dyskinetic areas. However, using both tracer techniques, akinesis could bedistinguished from dyskinesis. In patients with disturbed left ventricular function, cardiac transit times correlated with haemodynamic changes, and left ventricular ejection fraction was the most sensitive index. Thus, this combined radionuclide approach provides data for the evaluation of overall and regional wall function. A major advantage of this non-invasive auantitative technique is its applicability to the critically ill patient at the bedside.     

Enhanced detection of proximal right coronary artery stenosis with the additional analysis of right ventricular thallium-201 uptake in stress scintigrams

The value of right ventricular thallium-201 analysis in detecting proximal right coronary artery stenosis in exercise myocardial scintigraphy was analyzed in 52 patients, 27 with and 25 without proximal right coronary artery stenosis. For the detection of proximal right coronary artery stenosis, the sensitivity and specificity of thallium scintigraphic analysis were 59 and 88% for a right ventricular abnormality, 67 and 68% for a left ventricular inferior wall abnormality, and 93 and 56% for an abnormality of either. When both right and left ventricular thallium images were abnormal, all 9 patients had proximal right coronary artery stenoses, and when both were normal, 26 of 28 patients had a normal proximal right coronary artery. The sensitivity and specificity of blood pool scintigraphic variables during exercise (right ventricular ejection fraction and left ventricular inferior wall motion) were not significantly different for detection of proximal right coronary artery stenosis.Thus, the additional analysis of the right ventricle on thallium-201 stress scintigrams can improve the detection of proximal right coronary artery stenosis. When both right ventricular and left ventricular thallium scintigrams are abnormal (or normal), the ability to predict the presence (or absence) of proximal right coronary artery stenosis is very high.     

Site and severity of coronary narrowing and infarct size in man.

The relation between the site and severity of coronary artery lesion and infarct size was investigated in 59 patients with acute myocardial infarction. All patients had no prior myocardial infarction and had at least one significant coronary narrowing (greater than or equal to 75%) in one of the major coronary arteries or in the first diagonal branch. Left ventriculography and selective coronary arteriography were performed on average 2.2 months after the onset of infarction to identify the site and severity of coronary narrowing and to assess the extent of the non-contracting segment (akinetic, dyskinetic, or aneurysmal). Thirty-four of 59 patients were studied enzymatically and total CK released was taken as an indication of infarct size. Non-contracting segment and total CK released in group L-I (narrowing proximal to the first diagonal branch) were significantly larger than those in group L-II (a coronary lesion distal to the branch). The data also indicate that the perfusion area of the first diagonal branch is as large as that of the left anterior descending artery below the first diagonal branch. In contrast to left anterior descending artery disease, the involvement of the right ventricular branch did not significantly influence the infarct size. However, infarct size was significantly larger in eight patients with the left ventricular branch of the right coronary artery supplying the predominantly large area of posterior wall of the left ventricle than in nine patients with small left ventricular branches. It was also shown that the severity of coronary narrowing does not correlate with the infarct size in either left anterior descending or right coronary artery disease.     

Myocardial perfusion and left ventricular function during exercise evaluated by 201Tl myocardial scintigraphy and 99mTc radionuclide ventriculography in patients treated with PTCA]

To evaluate the effects of percutaneous transluminal coronary angioplasty (PTCA), we investigated myocardial ischemia and left ventricular function during exercise before and after successful PTCA in 30 patients. We used extent and severity scores of 201thallium (201Tl) exercise myocardial scintigraphy to assess myocardial ischemia and determined global and regional left ventricular ejection fraction (EF and REF) of 99mTc-RBC exercise radionuclide ventriculography to assess left ventricular function. The extent and severity scores of stress images were significantly less after PTCA than before PTCA. The scores of the redistribution images were unchanged before and after PTCA. Global EF during exercise was significantly higher after PTCA than before PTCA. There was no difference in resting global EF between before and after PTCA. Myocardial ischemia induced by exercise was semi-quantitatively analyzed as transient perfusion defect with severity score. Severity score was significantly less after PTCA than before PTCA. delta EF, which was obtained by subtraction of resting global EF from exercise one, was significantly higher after PTCA than before PTCA. However, the degree of improvement in myocardial ischemia and left ventricular function varied from patient to patient. In 17 patients with one-vessel left anterior descending artery disease, delta REF, which was determined by subtracting resting regional EF from exercise one, was significantly higher in septal and apical segments after PTCA than before PTCA. Myocardial ischemia and left ventricular function under exercise were alleviated by PTCA. However, the degree of improvement varied from patient to patient and it might have been affected by various factors including coronary dissection, edema, thrombus, restenosis, spasm, side branch stenosis or occlusion, distal thrombus, and myocardial hibernation.     

The ischemic segment and left ventricular function during exercise angina

Improvement of the quality of transpulmonary left ventriculograms by exercise was demonstrated in 5 patients in a pre-study. In the main study transpulmonary left ventriculography was performed in 10 patients with coronary artery disease (CAD) at rest and during exercise, producing maximum angina pectoris (AP). Left ventricular pressure was recorded simultaneously. The extent of CAD, demonstrated in all patients by coronary angiography, was quantitated by a score. In the exercise ventriculograms, local wall motion was quantitated by 14 hemiaxes. During exercise AP, all patients developed wall motion abnormalities not present at rest. There was a significant linear correlation between coronary score and number of abmormally shortening hemiaxes (< 30% shortening) during exercise-AP (y = 0.16 × + 4.34; r = 0.933). The number of anormal hemiaxes correlated significantly (p < 0.05) with left ventricular enddiastolic pressure (LVEDP), dp/dt min, endsystolic volume index, enddiastolic volume index, ejection fraction, stroke work index, minute work, compliance SV/ Δ PD/ESV, and cardiac index. During exercise AP the extent of ischemic wall motion abnormalities is determined by localization and severity of coronary artery lesions. The extent of ischemic impairment of wall motion determines the severity of impairment of left ventricular pump function, filling pressure, and maximum speed of relaxation. Transpulmonary left ventriculography during exercise AP is a safe and relatively simple method to quantitate the extent of ischemic wall motion abnormalities. It could be useful in the selection of patients for coronary artery surgery and in the assessment of the results of this operation.     

Two-dimensional echocardiographic evaluation of ventricular asynergy induced by dipyridamole: correlation with thallium scanning

Myocardial asynergies detected by two-dimensional echocardiography during intravenous administration of Dipyridamole (0.75 mg/kg) were evaluated in 54 patients referred for angiographic evaluation of chest pain. Technically adequate two-dimensional echocardiograms suitable for analysis were recorded in 42 of 54 (77.7%) patients studied. Thallium-201 myocardial perfusion scintigraphy, during dipyridamole test was performed in the same patients. Thirty of the 42 patients studied showed significant coronary narrowing at cardiac catheterization. Dipyridamole-induced wall motion abnormalities and myocardial perfusion defects were detected, respectively, in 19 (63.3%) and 21 (70%) of 30 patients with significant coronary artery disease. Wall by wall comparison of the distribution of dipyridamole-induced echocardiographic asynergy with reversible thallium-201 (201Tl) perfusion defects demonstrated complete correlation in 42 segments examined. Three segments with perfusion defects at thallium scanning did not show asynergy during the test while two segments showing wall motion abnormalities during dipyridamole infusion did not manifest perfusion defects. Our study demonstrates that two-dimensional echocardiography during dipyridamole testing is useful in detecting patients with coronary artery disease. Furthermore, ventricular asynergies detected during the test show a high correspondence with site of myocardial perfusion defects at thallium scanning.