Intravenous myocardial contrast echocardiography predicts regional and global left ventricular remodelling after acute myocardial infarction: comparison with low dose dobutamine stress echocardiography.

OBJECTIVE: To assess the role of intravenous myocardial contrast echocardiography (MCE) in predicting functional recovery and regional or global left ventricular (LV) remodelling after acute myocardial infarction (AMI) compared with low dose dobutamine stress echocardiography (LDSE). METHODS: 21 patients with anterior AMI and successful primary angioplasty underwent MCE and LDSE during the subacute stage (2-4 weeks after AMI). Myocardial perfusion and contractile reserve were assessed in each segment (12 segment model) with MCE and LDSE. The 118 dyssynergic segments in the subacute stage were classified as recovered, unchanged, or remodelled according to wall motion at six months' follow up. Percentage increase in LV end diastolic volume (%DeltaEDV) was also calculated. RESULTS: The presence of perfusion was less accurate than the presence of contractile reserve in predicting regional recovery (55% v 81%, p < 0.0001). However, the absence of perfusion was more accurate than the absence of contractile reserve in predicting regional remodelling (83% v 48%, p < 0.0001). The number of segments without perfusion was an independent predictor of %DeltaEDV, whereas the number of segments without contractile reserve was not. The area under the receiver operating characteristic curve showed that the number of segments without perfusion predicted substantial LV dilatation (%DeltaEDV > 20%) more accurately than did the number of segments without contractile reserve (0.88 v 0.72). CONCLUSION: In successfully revascularised patients with AMI, myocardial perfusion assessed by MCE is predictive of regional and global LV remodelling rather than of functional recovery, whereas contractile reserve assessed by LDSE is predictive of functional recovery rather than of LV remodelling.

Assessment of myocardial viability using coronary zero flow pressure after successful angioplasty in patients with acute anterior myocardial infarction.

OBJECTIVES: To investigate the relation between coronary flow reserve (CFR), coronary zero flow pressure (Pzf), and residual myocardial viability in patients with acute myocardial infarction. DESIGNS: Prospective study. SETTING: Primary care hospital. PATIENTS: 27 consecutive patients with acute anterior myocardial infarction. MAIN OUTCOME MEASURES: F-fluorodeoxyglucose (FDG) positron emission tomography (PET) was used in 27 patients who underwent successful intervention within 12 hours of onset of a first acute anterior myocardial infarction. Within three days before discharge they had < 25% stenosis in the culprit lesion as determined by angiography 24 (3) days after acute myocardial infarction. Pzf and the slope index of the flow-pressure relation (SIFP) were calculated from the simultaneously recorded aortic pressure and coronary flow velocity signals at peak hyperaemia.%FDG was quantified by comparing FDG uptake in the infarct myocardium with FDG uptake in the normal myocardium. RESULTS: There was a correlation between %FDG and CFR, where y = -1.477x + 62.517, r = -0.072 (NS). There was also a correlation between %FDG and SIFP, where y = -0.975x + 60.542, r = -0.045 (NS), and a significant correlation between %FDG and Pzf, where y = -0.98x + 85.108, r = -0.696 (p < 0.001). CONCLUSIONS: CFR does not correlate with FDG-PET at the time of postreperfusion evaluation of residual myocardial viability. The parameter that correlates best with residual myocardial viability is Pzf and this may be a useful index for predicting patient prognosis.

Dobutamine stress electrocardiography-gated Tc-99m tetrofosmin SPECT for detection of viable but dysfunctional myocardium.

BACKGROUND: Technetium-99m-labeled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function by electrocardiography-gated scan. This study was performed to determine whether dobutamine stress electrocardiography-gated tetrofosmin single photon emission computed tomography (SPECT) can identify viable (as defined by positron emission tomography [PET]) but dysfunctional myocardium with contractile reserve. METHODS AND RESULTS: Thirty-five patients with myocardial infarction underwent resting electrocardiography-gated SPECT and fluorodeoxyglucose (FDG) PET. The relative uptakes of tetrofosmin (%tetrofosmin) and FDG (%FDG) were calculated. Wall motion in 9 left ventricular segments was assessed at rest and during dobutamine stress on a 3-dimensional cine-mode display created with automatic left ventricular function analysis software. A total of 129 dysfunctional segments were analyzed. Forty-five (48.9%) of 92 segments with %tetrofosmin of 50% or greater and only 4 (10.8%) of 37 segments with %tetrofosmin less than 50% had contractile reserves (P <.0001). The sensitivity, specificity, and predictive accuracy of %tetrofosmin of 50% or greater for detecting %FDG of 50% or greater were 85.7%, 74%, and 82.9%, respectively. The incidence of the presence of contractile reserve rose with increasing magnitude of %FDG. The sensitivity, specificity, and predictive accuracy of the presence of contractile reserve for detecting %FDG of 50% or greater were 43.9%, 80.6%, and 52.7%, respectively. CONCLUSIONS: Dobutamine stress electrocardiography-gated SPECT can identify viable (as defined by PET) but dysfunctional myocardium with contractile reserve.

A reverse flow-metabolism mismatch pattern: a new marker of viable myocardium with greater contractility during dobutamine stress than myocardium with a flow-metabolism mismatch pattern.

Few studies have investigated the contractility of myocardium with a reverse flow-metabolism pattern; that is, greater uptake of nitrogen- 13-ammonia (NH3) than fluorine- 18-fluorodeoxyglucose (FDG) on positron emission tomography (PET). This study examined the contraction thickening represented by count increase in ECG-gated FDG-PET of myocardium with a reverse flow-metabolism pattern during low-dose dobutamine stress. Fifty-four patients with myocardial infarction were studied. Relative NH3 and FDG uptake (%NH3, %FDG) and %count increase were measured in 216 apical and 216 lateral segments on ECG-gated FDG-PET. The %count increase during low-dose dobutamine stress was greater in myocardium with a reverse flow-metabolism mismatch pattern than in myocardium with a flow-metabolism mismatch pattern (35.9+/-25.7% vs 24.6+/-15.9%, p=0.0221 in apical segments, and 38.4+/-22.6% vs 27.6+/-18.4%, p=0.0040 in lateral segments) despite smaller %FDG. A reverse flow-metabolism mismatch pattern should be noted as a new marker of viable myocardium with greater contractility during dobutamine stress than myocardium with a flow-metabolism mismatch pattern.

Reverse redistribution of thallium-201 myocardial single photon emission tomography and contractile reserve.

The present study investigated the contractile reserve of myocardium exhibiting reverse redistribution (RRD) of thallium-201 (201Tl) after acute myocardial infarction. Forty patients experiencing their first acute myocardial infarction underwent resting 201Tl single-photon emission computed tomography (SPECT) and low-dose (5-10 microgxkg(-1)xmin(-1)) dobutamine stress echocardiography (DSE) within 4 weeks after the onset of infarction. The left ventricle was divided into 13 segments for analysis. The severity of defects in 201Tl SPECT and the extent of wall motion abnormality in DSE were visually assessed and scored. The sum of each defect score and wall motion score of infarct-related segments were defined as total defect score (TDS) and total wall motion score (TWM), respectively. Quantitative analysis of 201Tl uptake was also performed. Resting 201Tl SPECT revealed RRD in 16 patients (group RRD), fixed defect (FIX) in 23 patients (group FIX), and redistribution in one. There was a significant difference in improvement of TWM between rest and stress in TWM in both the RRD and FIX groups (p<0.0001, each case). The improvement of TWM with dobutamine was significantly greater in RRD than in FIX (1.6+/-1.0 vs 0.6+/-0.7, p=0.001). There was a positive correlation between the magnitude of RRD and improvement of TWM with dobutamine (r=0.48, p=0.002). Myocardium exhibiting RRD on 201Tl SPECT in patients with acute myocardial infarction has greater contractile reserve than that exhibiting a fixed defect.

Effects of preinfarction angina on myocardial injury in patients with acute myocardial infarction: a study with resting 123I-BMIPP and 201T1 myocardial SPECT.

METHODS: Recent studies have suggested that patients with preinfarction angina have smaller infarcts and a better in-hospital outcome than those without angina. The mechanisms responsible for limitation of infarct size in the presence of preinfarction angina are unclear. We examined the effects of preinfarction angina on myocardial injury in patients with the first acute myocardial infarction with resting 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) 201TI myocardial scanning performed within 1 mo of infarction. RESULTS: Of 136 patients tested, 48 (35%) had preinfarction angina within 72 h before infarction, whereas 88 (65%) did not. BMIPP and 201TI defects were scored in 9 segments of the left ventricle (0 = normal, 1 = mild defect, 2 = moderate defect, 3 = severe defect, and 4 = no uptake). The total defect score was defined as the sum of the defect scores. There was no significant difference in percentage diameters of stenoses of infarct-related arteries, collateral circulation, total defect scores for BMIPP, or 201TI between the groups with and without preinfarction angina. However, the ratio of total defect score for 201TI to that for BMIPP was significantly smaller for patients with than for those without preinfarction angina (0.64 +/- 0.21 versus 0.74 +/- 0.25, respectively; P = 0.007). CONCLUSION: Preinfarction angina did not affect the areas at risk in acute myocardial infarction, as shown by BMIPP defect, but decreased necrotic myocardium in the areas at risk, as shown by 201TI defect, and increased metabolically damaged but viable myocardium, as shown by BMIPP and 201TI mismatch through unidentified mechanisms other than collateral circulation (e.g., ischemic preconditioning).

Dobutamine-stress electrocardiographically gated positron emission tomography for detection of viable but dysfunctional myocardium.

PURPOSE: This study was performed to determine whether low-dose dobutamine stress electrocardiography (ECG)-gated fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) can assess wall motion and identify myocardium without contractile reserve despite preserved FDG uptake. METHODS: Fifty-three patients with myocardial infarction and normal sinus rhythm underwent ECG-gated FDG-PET and transthoracic echocardiography. Wall motion of 10 segments of the left ventricle was graded as normal, hypokinetic, or akinetic/dyskinetic. RESULTS: In 365 (76%) of 480 segments, assessment of wall motion was concordant between the 2 modalities. In 30 patients dobutamine-stress ECG-gated FDG-PET was performed. In 13 (50%) of 26 dysfunctional segments with normal FDG uptake, 16 (36%) of 44 dysfunctional segments with mildly reduced FDG uptake and 12 (25%) of 48 dysfunctional segments with moderately reduced FDG uptake, wall motion was improved by dobutamine infusion. CONCLUSION: Assessment of left ventricular wall motion with ECG-gated FDG-PET is feasible, and dobutamine stress ECG-gated FDG-PET can simultaneously identify metabolic viability and contractile reserve.

Usefulness of newly designed pigtail catheter with multiple side holes by reducing incidence of ventricular ectopy.

This study was designed to determine whether a newly designed 5 Fr pigtail catheter of Jet Balance with multiple side holes reduces the incidence of ventricular ectopy during left ventriculography. To examine the catheter movement in vitro, we injected a colored glycerin solution by an injector through 5 Fr Jet Balance catheter and 6 Fr conventional pigtail catheter suspended in a water filled, glass container. A recoil of the catheter caused by injection was observed for a 6 Fr conventional catheter; however, no catheter movement was observed when a 5 Fr Jet Balance was used. To evaluate clinical usefulness of the 5 Fr Jet Balance, we compared the number of incidence of ventricular ectopy during left ventriculography between 5 Fr Jet Balance and 6 Fr conventional pigtail catheters. In 104 consecutive patients who underwent left ventriculography, a 5 Fr Jet Balance was used in 55 patients (5 Fr Jet Balance group), and a 6 Fr conventional pigtail in 49 patients (6 Fr conventional pigtail group). The 5 Fr Jet Balance group had a significantly lower incidence of VPB (21.8% vs. 42.9%, P = 0.02), ventricular tachycardia (1.9% vs. 14.3%, P = 0.02), and multiple VPB (9.0% vs. 34.7%, P = 0.001), respectively, than the 6 Fr conventional pigtail group. In conclusion, a 5 Fr Jet Balance pigtail catheter is useful and safe as regard to the incidence of ventricular ectopy during left ventriculography. Cathet. Cardiovasc. Intervent. 48:220-225, 1999.

A reverse flow-metabolism mismatch pattern on PET is related to multivessel disease in patients with acute myocardial infarction.

UNLABELLED: Hypoperfused myocardium with increased uptake of 18F-fluorodeoxyglucose (FDG) is considered to be ischemic but viable myocardium. However, the significance of a more severe defect of FDG than of 13N ammonia (NH3) (i.e., reverse flow-metabolism mismatch) is not well understood. METHODS: To study a reverse flow-metabolism mismatch pattern, PET with NH3 and FDG under glucose loading was performed in 35 patients within 2 wk after onset of first acute myocardial infarction (AMI) and in 29 patients with old myocardial infarction (OMI). The left ventricle was divided into nine segments on a bull's eye polar map, and the mean counts of NH3 (%NH3) and FDG (%FDG) were compared for the segment with the least %NH3. RESULTS: Ten patients in the AMI group demonstrated a marked reverse flow-metabolism mismatch pattern (greater than 10% difference between %NH3 and %FDG), whereas only 2 patients in the OMI group demonstrated the mismatch pattern (P < 0.05). Sixteen patients with AMI demonstrated %FDG > %NH3 (group 1), and 19 patients with AMI demonstrated %FDG < %NH3 (group 2). There were no significant differences in age, sex, location of infarction, diameter of stenosis of infarct-related artery or left ventricular ejection fraction between groups 1 and 2. Eleven patients in group 2 and only 3 in group 1 had multivessel disease (P < 0.02). There was no significant relationship between the number of diseased vessels and the flow-metabolism pattern in patients with OMI. CONCLUSION: The finding of a reverse flow-metabolism mismatch on PET in the subacute phase of myocardial infarction was closely related to multivessel disease.

Detection of a biphasic response of hibernating myocardium by dobutamine-stress electrocardiography-gated technetium-99m-tetrofosmin single photon emission computed tomography--a case report.

A woman with coronary artery disease underwent a new imaging technique: dobutamine-stress electrocardiography (ECG)-gated tetrofosmin-single photon emission computed tomography (SPECT). Dobutamine-stress ECG-gated tetrofosmin-SPECT with automatic left ventricular function analysis software programs detected improvement and a biphasic response of dysfunctional myocardium during dobutamine infusion, which suggested viable but hibernating myocardium. Dobutamine-stress ECG-gated tetrofosmin-SPECT with automatic left ventricular function analysis software programs has the potential to detect viable but dysfunctional myocardium with contractile reserve.

Influence of inoculation site of combined oil-adjuvanted vaccine on the antibody response in chickens.

Inactivated oil-adjuvanted vaccines for ND, IB, and IC serotypes A and C (OILVAX NB2AC) have been marketed from 1993. In the outdoors, various inoculation sites have been used in chickens because to make the inoculation procedure easier. We examined whether differences would be obtained in the antibody response according to the inoculation sites; the subcutaneous inoculation into the back of the neck for OILVAX use, and the thigh, lower thigh, breast and shoulder muscle for the possible application of the inoculation outdoors. The clear order was not found in the NDV-HI titer, IBV-SN titer against Nerima or TM-86 among the inoculation sites used during the examination period. The IC serotypes A and C HI titers did vary among the inoculation sites; the subcutaneous inoculation produced the highest antibody titer, and high antibody titers were observed in the order of lower thigh muscle > or = thigh muscle > breast muscle > or = shoulder muscle inoculation.

Aortic regurgitation in a patient with primary antiphospholipid syndrome--a case report.

We present the case of a 39-year-old woman with aortic regurgitation that may have been induced by primary antiphospholipid syndrome. The patient had suffered recurrent miscarriages, thrombocytopenia, and deep-vein thrombosis for the previous 16 years, and had been diagnosed as having primary antiphospholipid syndrome 9 years previously because of a high titer of anticardiolipin antibody. She had been receiving medication for moderate hypertension for 7 years. The patient was admitted to Tenri Hospital because of heart failure, which was thought to be caused by moderate aortic regurgitation, moderate hypertension, and mild chronic renal failure. Echocardiography revealed thickened aortic and mitral valves. Primary antiphospholipid syndrome might have induced valve regurgitation as a result of valvular thickening.

Problems in pharmacological evaluation of patients with paroxysmal atrial fibrillation: clinical analysis of more than 100 consecutive patients.

To address the problems of pharmacological evaluation in paroxysmal atrial fibrillation (PAf), we interviewed 108 consecutive patients with documented PAf regarding symptoms, frequency and trigger factors of PAf and analyzed the 24-hour ambulatory electrocardiographic monitoring (Holter monitoring) records in relation to symptoms. Twenty-nine patients were totally asymptomatic, while 79 patients were symptomatic of which 49 patients had obvious trigger factors. PAf was documented by Holter monitoring in 22 of 79 symptomatic patients. On analysis of PAf-documented 25 Holter monitoring records, the patients checked event marks as PAf in only 20 of 155 PAf episodes. Six episodes of 26 event marks that patients thought to be PAf proved to be premature atrial or ventricular contractions. Nine patients in whom PAf persisted for more than 24 hours became asymptomatic. Patients suitable for pharmacological evaluation constituted about one-fifth of the PAf patients in our consecutive study. Even with the selection of these patients, pharmacological evaluation based on symptoms is difficult because disappearance of PAf may be associated with persistent atrial fibrillation.

Problems in the initial diagnosis of renal infarction.

We retrospectively analyzed 20 cases of renal infarction to identify the problems in tentatively diagnosing renal infarction. The subjects consisted of 12 outpatients and 8 inpatients whose diagnosis was confirmed by renal scintigram and/or contrast computed tomography. Renal infarction was tentatively diagnosed in only 4 of the 12 outpatients. Causes of hospitalization were cerebral emboli in 5 cases, peripheral emboli in the extremities in 2 cases and one case involved percutaneous transmitral commissurotomy. On initial urinalysis, 11 cases (55%) showed less than 2+ hematuria using dipsticks to test for occult blood. The mean lactic dehydrogenase value was as high as 2,096 IU while the mean aspartate aminotransferase and mean alanine aminotransferase were 83.1 IU and 78.6 IU. Abdominal ultrasonography revealed abnormalities in only one of 18 cases. In conclusion, since only a moderate degree of hematuria was seen in about half the cases and it was difficult to detect renal abnormalities by ultrasonography, a tentative diagnosis of renal infarction may be difficult in some cases.

Trans-systolic murmur during the Valsalva maneuver in a patient with apical aneurysm--a case report.

We present a 74-year-old female in whom a systolic murmur became trans-systolic during the Valsalva maneuver. The patient had had stable effort angina for 20 years and coronary angiography revealed complete obstruction of the left anterior descending artery in addition to other atherosclerotic lesions. Left ventriculography showed a small apical aneurysm with a narrow orifice. Aorto-coronary bypass surgery and aneurysmectomy were performed; true aneurysm was confirmed pathologically. We conclude that apical aneurysm with a narrow orifice can produce trans-systolic murmur.

Variable activity of protein tyrosine kinase in apparently normal thyroid glands.

We examined protein tyrosine kinase (PTK) activity in apparently normal thyroid tissue (n = 22) obtained from patients undergoing thyroid surgery for papillary thyroid cancer or benign disease. The PTK activity in apparently normal thyroid tissue from patients with papillary thyroid cancer progressively was elevated in the cytosolic fraction compared with that from patients without cancer (p < 0.05). The cytosolic proportion of PTK activity was also significantly increased in the normal thyroid tissue of patients with cancer (62% vs. 51%, p < 0.05). These findings suggest that alterations in PTK activity may indicate apparently normal thyroid tissue at increased risk of developing malignancy.

Anorectal function after preoperative intraluminal brachytherapy and colonic J pouch-anal anastomosis for rectal carcinoma.

The effects of preoperative intraluminal brachytherapy on bowel function after anoabdominal rectal resection and colonic J pouch-anal anastomosis were studied. The patients included eight not receiving irradiation (group 1), eight who received 30 Gy (group 2) and eight who received 80 Gy (group 3). Stool frequency and the incidence of soiling were significantly greater in group 3 than in the other groups. Anal resting pressure was lower in group 3 during the study period but J pouch distensibility was not reduced. The maximum tolerated volume, threshold volume and squeeze pressure were significantly lower in group 3 than in the other groups in the early postoperative period. These results suggest that high-dose brachytherapy affects the anal sphincters and colonic J pouch. A moderate dose of 30 Gy may be more suitable before restorative anorectal surgery.