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To assess the morphologic correlate of the presence and absence of pathologic Q waves in the electrocardiogram, 30 patients with and 17 patients without pathologic Q waves and chronic myocardial infarction (infarct age >4 months) and 15 patients without previous myocardial infarction but significant coronary artery disease (>70% diameter stenoses) were studied by gradient-echo magnetic resonance imaging (MRI). Short-axis MRI tomograms were evaluated on a segmental basis by calculating end-diastolic wall thickness and systolic wall thickening. All segments were graded transmural scar (end-diastolic wall thickness < end-diastolic wall thickness of a healthy control group [n = 21] - 2.5 SD and lack of systolic wall thickening), hypokinetic (end-diastolic wall thickness [greater than or equal to] end-diastolic wall thickness of the control group - 2.5 SD and systolic wall thickening [less than or equal to] 2 mm), or normal (end-diastolic wall thickness [greater than or equal to] end-diastolic wall thickness of the control group - 2.5 SD and systolic wall thickening >2 mm) by MRI criteria. Myocardial infarcts were defined as transmural if at least 1 segment fulfilled the MRI criteria for transmural scar. Of 30 patients with Q-wave infarction, 26 (87%) had a transmural defect, and 6 of 17 patients (35%) with non-Q-wave infarction had a transmural infarct. Segmental evaluation yielded 129 of 480 scar segments (27%) for patients with Q-wave infarction, 20 of 272 scar segments (7%) for patients with non-Q-wave infarction, and no scar segments for patients without previous myocardial infarction. The proportion of segments graded transmural scar was significantly (p

A low primary success and high restenosis rate after recanalization of chronic total occlusions by conventional coronary angloplasty have encouraged the application of new interventional techniques like excimer-laser angloplasty. in 39 patients with a coronary occlusion for 1 to 12 months, recanalization was attempted by laser angloplasty through a multifiber-catheter coupled to a pulsed XeCl excimer laser. After successful passage of the occlusion by a standard guidewire in 27 patients (69%), the laser catheter was advanced over the central guidewire and crossed the occlusion in 2S patients (64%). In 2 patients with unsuccessful passage of the laser catheter, the subsequent attempt with a low prefile balloon catheter also falled. In 19 of the 25 patients with successful laser recanalization, the residual stenosis exceeded 50% and was therefore followed by additional balloon angioplasty. The average residual stenosis after laser was 61 +/17% of the vessel diameter, and after balloon angioplasty 28 +/- 9% (n = 19), whereas after laser angioplasty alone it was 38 +/- 5% (n = 6). No compilcations associated with the laser application were observed. Angiographic control after 24 hours showed a reocclusion of 2 (8%) recanalized vessels. In this pilot study, laser angioplasty proved to be a safe and feasible method for the treatment of chronic total coronary occlusions. Because it was necessary to guide the catheter by a central wire, the primary success was limited by a successful passage of the wire of the occlusion. The rate of stand-alone laser angioplasty has to be increased by future improvements of the technique to enable a comparative evaluation of this method with conventional angioplasty. (Am J Cardiol 1990;66:1445-1450), Coronary artery disease (CAD) is a condition in which the coronary arteries, which supply the heart with blood, become blocked, depriving the heart muscle of blood and oxygen. This is often caused by a buildup of fatty atherosclerotic plaques on the inner surfaces of the coronary arteries. When untreated, this can lead to death. The most common nonsurgical treatment for CAD is percutaneous transluminal coronary angioplasty, in which a balloon-tipped catheter is advanced to the point of occlusion and inflated, thereby opening the blood vessel. Improvements in balloon design have increased the immediate success rate for this procedure, but the high occurrence of restenosis (further blockage of the artery) limits the long-term success rate. One innovation that has the potential to reduce the incidence of restenosis is laser angioplasty, in which the blockage is eliminated by application of laser energy to the atherosclerotic plaque. In 39 patients with total occlusion of at least one coronary artery, recanalization (removal of the stenosis) was attempted by introducing a multifiber catheter connected to a pulsed xenon chloride excimer (gas) laser into the occluded artery. In 25 patients with successful laser recanalization, the degree of arterial occlusion was still greater than 50 percent. Consequently, the laser procedure was followed by standard balloon angioplasty. Fourteen of the patients' occlusions were inaccessible to the laser cannula. The degree of residual stenosis following combined laser and balloon angioplasty was 28 percent of the vessel diameter, while following laser angioplasty it was 61 percent, indicating the greater efficacy of the combined treatments. Angiographic visualization of arterial patency (degree of openness) 24 hours later showed that eight percent of the arteries had undergone restenosis. (Consumer Summary produced by Reliance Medical Information, Inc.)

In an attempt to detect occult or intermittent rhinorrhea, 10 patients without and 9 cases with rhinorrhea were investigated after a lumbal injection of 1.3 mCi 111In-DTPA. Significant count rates were detectable in the nasal pledgets of all individuals, so that it was not possible to distinguish those with and those without rhinorrhea. Therefore, the ratio of activity in nasal pledgets and blood normalized for weight recommended by McKusick et al. was used. In the patients without evidence of rhinorrhea, the ratio did not exceed 2.0, whereas in 8 of the 9 cases with rhinorrhea, it was considerably increased. The detectability of rhinorrhea was increased by using more than one measurement and by provocation manoeuvres.

Magnetic resonance imaging (MRI) has been used in conjunction with dipyridamole induced wall motion abnormalities for the noninvasive detection of coronary artery disease (CAD). To assess the clinical usefulness of dipyridamole-MRI for the localization of CAD and to evaluate the relation between dipyridamole induced wall motion abnormalities and myocardial perfusion 33 patients with severe CAD (>70% diameter reduction) underwent MRI at rest and after dipyridamole infusion (0.75 mg dipyridamole/kg over a period of 10 minutes). All patients performed exercise stress testing and 20 patients of the study group additionally had rest and exercise stress99mTc-methoxyisobutyl-isonitrile-SPECT (MIBI-SPECT). Two patients (6%) could not be evaluated due to severe motion artifacts during dipyridamole MRI.

Dobutamine pharmacological stress testing in conjunction with technetium-99m methoxyisobutylisonitrile single-photon emission tomography (MIBI SPET) may be a useful alternative to convential exercise stress MIBI SPET for the detection and localisation of coronary artery stenoses. Therefore, 35 patients with stenoses (= 50% diameter reduction) of one or more coronary arteries were selected for dobutamine MIBI SPET. Each patient underwent MIBI injection at rest and during dobutamine infusion with incremental doses (5, 10, 15 and 20 µg kg-1 min-1). A conventional exercise stress test (EST) was performed in all patients. Peak double product during steady-state dobutamine infusion (18 200 ± 4200 mmHg min-1) was lower (P = 0.0001) than during EST (21 700 ± 4900 mmHg min-1). Image quality was good in all but one patient, who had to be excluded from data analysis due to excessive hepatobiliary MIBI activity. Dobutamine-induced perfusion abnormalities were observed in 30/34 MIBI SPET studies, resulting in an overall detection rate for coronary artery disease of 88%. A pathological EST was observed in 23/34 patients (68%). The detection rate of individual coronary artery stenoses was 85% (28/33) for stenosess with a severe diameter reduction (>70%) and 50% (12/24) for stenoses with a moderate diameter reduction (= 50–70%). In particular, sensitivity and specificity for the detection of moderate and severe stenoses (= 50%) were 75%/100% for left anterior descending, 67%/95% for left circumflex and 67%/69% for right coronary artery stenoses. Dobutamine MIBI SPET is a well-tolerated, non-exercise-dependent test for detection and localisation of haemodynamically significant coronary artery stenoses. The use of dobutamine allows a stepwise increase in pharmacological stress similar to EST and is especially useful in patients who are unable to exercise.

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