Comparison between rest technetium-99m-tetrofosmin and rest-redistribution thallium-201 SPECT in stable patients with healed myocardial infarction.

Resting (99m)Tc-tetrofosmin (TF) uptake was compared with thallium ((201)Tl) rest-redistribution (R-RD) uptake in patients with previous myocardial infarction (MI) and significant coronary artery disease (CAD) to assess the ability of TF to detect viable myocardium. We studied 30 patients (21 males and nine females, mean age 53.9+/-12.5 years) with prior MI and left ventricular dysfunction who had been referred for coronary revascularization procedures. Myocardial single photon emission computed tomography (SPECT) images were obtained 1 h after injection of 750 MBq of TF. Within 1 week of the TF study, R-RD (201)Tl SPECT imaging was performed after injection of 111 MBq of (201)Tl . Quantitative analysis was performed in 21 segments. Viability was defined as the presence of tracer uptake greater than 50% of the peak activity on baseline studies or after reversibility. There was significant correlation between the quantitative regional R-RD (201)Tl activity and the resting TF activity (r=0.88, P<0.001). Quantitative analysis showed that the uptake of the two tracers was comparable in normal segments as well as in segments with fixed (201)Tl defects. In contrast, in segments with reversible (201)Tl defects, TF uptake was significantly greater than resting (201)Tl uptake, but lower than R-RD (201)Tl uptake. There were 52 segments (47% of the severely reduced segments on TF images) that showed no viability with TF, but were viable on the redistribution (201)Tl studies. We conclude that quantitative resting TF SPECT underestimates the presence of viable myocardium compared with R-RD (201)Tl imaging on the basis of using 50% of the peak activity as the viability threshold.

Complications associated with percutaneous placement of intra-aortic balloon counterpulsation: can unsheathed insertion reduce limb ischaemia?

Complications related to percutaneous placement of intra-aortic balloon pump counterpulsation are still high despite major refinements in catheter design and techniques. One hundred and forty-eight patients in whom intra-aortic balloon pumping was inserted were classified into two groups on the basis of the insertion technique. Group I included 103 patients in whom the conventional percutaneous insertion was used. A sheathless insertion technique was used in group II (n = 45). The overall complication rate was 16.6% (25 of 150), in which lower limb ischaemia was the most common complication. The limb ischaemia was noted in 12 patients (11.5%) in group I and 4 patients (8.9%) in group II (statistically not significant). Peripheral vascular disease, diabetes mellitus and female gender were found to be significant predictors of limb ischaemia (p = 0.01, p = 0.02 and p = 0.03, respectively). In conclusion, sheathless insertion of intra-aortic balloon pump catheters does not reduce the incidence of limb ischaemia.

UHL's anomaly.

Uhl's anomaly is a rare congenital hypoplasia of the right ventricular (RV) myocardium. It can be seen together with some other congenital anomalies. Here we first report a 16-year-old male patient with Uhl's anomaly which appears with cardiac tamponade.

Effect of potential confounding factors on the thrombolysis in myocardial infarction (TIMI) trial frame count and its reproducibility.

BACKGROUND: The potential factors that introduce variability into TIMI frame count (TFC) have not been systematically investigated. The goal of this study was to determine if nitrate use, dye injection rate, catheter size, the phase of the cardiac cycle in which dye is injected, or heart rate affect the TFC and to investigate the reproducibility of the TFC. METHODS AND RESULTS: The dye injection rate was increased 1 mL/s, and angiography was repeated. A coronary angiogram was taken first with an 8F catheter and then with a 6F catheter. After taking angiograms, intracoronary nitrate was given to the patient, and the second angiography was performed. Basal heart rate was increased 20 beats/min, and angiography was repeated. Dye injection was performed at the beginning of systole and diastole. The TFC was not significantly changed by increasing the dye injection rate (P=0.467) or by changing catheter size (P=0.693). Nitrate administration significantly increased the TFC from 26.4+/-11.9 to 32.8+/-13.3 frames (P<0.001). Dye injection at the beginning of diastole significantly decreased the TFC from 30.1+/-8.8 to 24.4+/-7.9 frames (P<0.001) for the left coronary artery and from 24.16+/-4.49 to 21. 24+/-4.45 frames (P<0.001) for the right coronary artery. Increasing heart rate significantly decreased the TFC from 30.4+/-6.1 to 25. 3+/-7.2 frames (P<0.001). Intraobserver and interobserver reproducibility of the TFC was good (mean difference, 1.33+/-1.24 and 2.57+/-1.72 frames, respectively). CONCLUSIONS: Nitrate use, heart rate, and the phase of the cardiac cycle in which dye is injected had significant effects on the TFC. Therefore, studies comparing TFC need to consider these factors, and the use of nitrates should be either standardized or randomized.

Effect of diabetes mellitus on formation of coronary collateral vessels.

BACKGROUND: Although myocardial ischemia is known to be significantly related to the development of coronary collateral vessels (CCVs), there is considerable variation between patients with ischemic heart disease in the presence of collateral development. The nature of this variability is not well known. Likewise, it remains unclear whether diabetes mellitus (DM) has any effect on CCVs. The aim of this study was to evaluate the effect of DM on CCVs. METHODS AND RESULTS: Of the patients who underwent coronary angiography during the interval between March 1, 1993, and June 20, 1998, in our institution, 306 were diabetic. Those patients in whom coronary angiography is normal or severity of coronary artery stenosis is thought not to be sufficient for the development of CCVs (<75%) were excluded from the study. A total of 205 patients (mean age, 59+/-8 years) met the criteria for the DM group. For case-control matching, 205 consecutive nondiabetic patients (mean age, 58+/-9 years) who had >/=1 diseased vessel with >75% stenosis were included in the control group. The CCVs were graded according to the Rentrop scoring system, and the collateral score was calculated by summing the Rentrop numbers of every patient. There was no statistical difference between patients with and without DM in clinical baseline characteristics. The mean number of diseased vessels in the DM group (1.58+/-0.68) was higher than that in the nondiabetic group (1.42+/-0.65, P=0.005). The mean collateral score was 2.41+/-2.20 in the DM group and 2.60+/-2.39 in the control group. After confounding variables were controlled for, the collateral score in the diabetic group was significantly different from that in the nondiabetic group (P=0.034). CONCLUSIONS: Our findings suggest that CCV development is poorer in patients with than in patients without DM. Thus, we can speculate that DM is an important factor affecting CCV development.

Pharmacological profile of survivors of acute myocardial infarction at Turkish academic hospitals.

AIM: The purpose of this study was to document treatment profiles in 850 patients surviving acute myocardial infarction at 17 academic hospitals in Turkey. METHODS AND RESULTS: Pharmacological management data of acute myocardial infarction survivors were collected and divided into three categories: drugs which patients received before hospitalization, during the hospitalization, and at hospital discharge. Data regarding medical history, complications during hospitalization, MI extent (Q wave or non-Q wave), infarct location and diagnostic and revascularization procedures were also recorded. This study is based on the 850 patients who met the diagnostic criteria for initial acute MI in the period examined. Among 850 patients with myocardial infarction enrolled 408 (48%) received thrombolytic therapy. The median time interval from symptom onset to initiation of thrombolytic therapy was 196 min. The most commonly used thrombolytic agent was streptokinase (93%). Thrombolytic recipients were younger, and presented sooner after onset of symptoms. Among patients receiving thrombolytic therapy, concomitant pharmacotherapy included aspirin (95%), intravenous heparin (93%), intravenous nitroglycerin (91%), oral beta-blockers (44%), calcium channel antagonists (13%), and angiotensin converting enzyme inhibitors (41%). The lipid lowering therapy was only used in 4% of all patients, and was given to 18% of patients with hyperlipidemia. CONCLUSION: Current usage rates of thrombolytic therapy in Turkey are lower than expected, but when compared with previous reports it increased. Although adjunctive treatment with intravenous heparin and intravenous nitroglycerin is usually used, beta-blockers appear to be underused and calcium channel blockers appear to be overused. The lipid reducing therapies were infrequently prescribed.

Comparison of exercise stress testing with dobutamine stress echocardiography and radionuclide ventriculography for diagnosis of coronary artery disease.

Dobutamine stress echocardiography, Tc-99m radionuclide ventriculography (RNVG), and exercise stress testing were performed prospectively in 63 patients with suspected coronary artery disease to compare the values of exercise testing, dobutamine stress echocardiography and RNVG in the non-invasive diagnosis of coronary artery disease. The sensitivities of dobutamine stress echocardiography and RNVG were found to be higher than that of exercise testing (93-62%, p < 0.001; 83-62%, p < 0.05). The sensitivities of dobutamine stress echocardiography and RNVG were similar (p > 0.05). There were no differences between the sensitivities of the three techniques in multiple vessel disease (p > 0.05). The specificities of dobutamine stress echocardiography and RNVG were higher than that of exercise testing (for both of the tests 86-62%, p < 0.05). The diagnostic accuracy of dobutamine stress echocardiography and RNVG were similar (p > 0.05). The results of dobutamine stress echocardiography RNVG were concordant with each other in 46 patients (76%, kappa = 65%) in sectional analysis. Dobutamine stress echocardiography and RNVG tests were comparable with each other in 85% of the 189 segments (kappa = 64%). The expected 5% decrease at peak doses of dobutamine was not detected in stress echocardiography in 25 patients and in RNVG in 26 of the patients. Dobutamine stress echocardiography and RNVG are superior to exercise testing in the diagnosis of single vessel disease and there is no significant difference between the two techniques. When the ejection fraction is considered in dobutamine stress echocardiography and RNVG, it does not make an additional contribution to the diagnosis of coronary artery disease.

Plasma leukocyte elastase concentration and coronary artery disease.

It has previously been shown that leukocyte elastase is involved in the pathogenesis of atherosclerosis. Few studies have addressed the relation between leukocyte elastase concentrations and coronary artery disease (CAD). The authors investigated (1) the clinical significance of leukocyte elastase determination in the diagnosis of CAD and (2) the relation between plasma leukocyte elastase concentration and lesion morphology. The study included 185 subjects (140 men, 45 women) who underwent coronary angiography during investigation of chest pain; 135 had coronary stenosis (Group I) and 50 had nonstenotic coronaries (Group II). Among Group I patients, those with simple atheromatous plaques were distinguished from those with complex plaques. Elastase concentrations in Group I were greater than in Group II (57.1 +/- 1.16 micrograms I[-1] vs 27.6 +/- 1.0 microgram, I[-1], P<0.001), and greater in complex plaque patients than in those with simple plaques (64.5 +/- 1.24 micrograms I[-1] vs 45.9 +/- 1.01 micrograms I[-1], P<0.001). Logistic regression analysis showed (1) that elastase concentration, age, and sex had independent value for prediction of CAD and (2) that among Group I patients, the risk of complex plaques was greatest for those with high elastase concentration. These results suggest that plasma leukocyte elastase concentration is a sensitive diagnostic marker of CAD and that high values of elastase may indicate the presence of complex atheromatous plaques.

Comparison of exercise stress testing with dobutamine stress echocardiography and exercise technetium-99m isonitrile single photon emission computerized tomography for diagnosis of coronary artery disease.

To compare the value of exercise electrocardiography with dobutamine stress echocardiography and exercise technetium-99m isonitrile single-photon emission computed tomography for coronary artery disease, 70 patients with either suspected or proven coronary artery disease underwent dobutamine stress echocardiography, exercise technetium-99m isonitrile single-photon emission computed tomography (mibi-SPECT) and treadmill exercise electrocardiography (ECG). Dobutamine echocardiography and exercise mibi-SPECT revealed a higher overall sensitivity than exercise testing (90 vs 57%, p < 0.001; 96 vs 57%, p < 0.001, respectively). Dobutamine stress echocardiography showed a higher specificity than both exercise mibi-SPECT and treadmill exercise electrocardiography (90 vs 71%, p > 0.05; 90 and 62% p < 0.05, respectively) but the difference between dobutamine stress echocardiography and exercise mibi-SPECT was not statistically significant. Diagnostic accuracy of dobutamine stress echocardiography and exercise mibi-SPECT was higher than that of exercise testing (90 vs 59%, p < 0.001; 89 vs 59%, p < 0.001, respectively). Dobutamine stress echocardiography and exercise mibi-SPECT have superiority over exercise testing in the diagnosis of coronary artery disease and dobutamine stress echocardiography is an alternative for exercise mibi-SPECT.

Comparison of exercise stress testing with simultaneous dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computerized tomography for diagnosis of coronary artery disease.

The object of our study was to compare the value of exercise stress testing with simultaneous dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography for the diagnosis of coronary artery disease. Sixty-nine patients with either suspected or proven coronary artery disease underwent simultaneous dobutamine technetium-99m isonitrile single-photon emission computed tomography and stress echocardiography, and treadmill exercise electrocardiography. Dobutamine echocardiography and technetium-99m isonitrile single-photon emission computed tomography revealed a higher overall sensitivity than exercise testing (94 vs 60%, P < 0.001), but dobutamine stress echocardiography showed a higher specificity than both technetium-99m isonitrile single-photon emission computed tomography and exercise testing (86 vs 64%, P < 0.05, for both tests). In addition, the diagnostic accuracy of dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography was higher than that of exercise testing (91 vs 61%, P < 0.001; 86 vs 61%, P < 0.001, respectively). Dobutamine stress echocardiography and technetium-99m isonitrile single-photon emission computed tomography are superior to exercise testing in the diagnosis of coronary artery disease, and dobutamine stress echocardiography can act as an alternative to technetium-99m isonitrile single-photon emission computed tomography.