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In recent years follow-up trials on coronary artery disease with angiographic end points analyzed quantitatively have gained increasing relevance and popularity. There is no consensus, however, on the method of calculation of progression or regression from multiple angiographic projections. Therefore the influence of the selection of angiographic projections on the outcomes of such trials was investigated with the data of the International Nifedipine Trial on Antiatherosclerotic Therapy. In 348 patients with coronary artery disease, repeated coronary angiograms were compared in multiple identical angiographic projections. Changes in angiographic parameters were averaged over the 1063 stenoses analyzed. Five methods of evaluation of multiple projections in the individual stenoses were applied, resulting in different extents of overall progression, or even regression of coronary artery disease (p0.01). It is concluded that in quantitative coronary angiographic follow-up trials changes should be averaged over all angiographic projections available for a stenosis to avoid overestimation of progression or regression.

Intracoronary stenting was designed to handle acute vessel closure after balloon angioplasty and to reduce the rate of restenosis. In three cardiology centers the implantation of 200 balloon-expandable Palmaz-Schatz stents was attempted in 179 patients. The implantation was successful in 170 patients (95%). During bail-out implantation for acute vessel closure or symptomatic dissections after balloon angioplasty, implantation succeeded in 60 (91%) of 66 attempted patients, who recovered immediately from ischemia. Three patients received emergency bypass surgery and three patients were kept on medical therapy. Restenosis after 4 to 6 months, defined as50% diameter reduction, was documented angiographically in 18 (15.3%) of 118 presently controlled patients. Patients with single stent implantation (n = 106) presented a late restenosis rate of 10.4% in contrast to patients with multiple stent implantation (n = 12), who presented a restenosis rate of 58.4%. Similar results on restenosis were found for patients with elective and bail-out stent implantation. Acute thrombotic stent occlusion occurred in three patients (1.8%) during the first 24 h after stenting. Three to 9 days after implantation subacute stent thrombosis occurred in 15 (8.8%) of 170 patients. Despite adequate therapy including thrombolysis, balloon angioplasty or emergency bypass surgery in 14 of 15 patients Q-wave myocardial infarction was documented in six patients and non Q-wave myocardial infarction in five patients. The following parameters were identified as risk factors for the development of subacute stent thrombosis: bail-out indication, unstable angina, type C lesion, stenosis length1.5 cm, plaque area3.5 mm2, symptomatic dissection after balloon angioplasty, incomplete wrapping of the dissection after stenting and residual distal vessel irregularities after stenting. Bleeding complications occurred in 12.4% of the patients and were related to the anticoagulation and antiaggregation therapy. In conclusion, the implantation of Palmaz-Schatz stents is an excellent bail-out device to treat acute vessel closure or symptomatic dissections after angioplasty. Elective and bail-out single stent implantation is associated with a reduced rate of restenosis when compared to conventional balloon angioplasty. At present, subacute stent thrombosis and bleeding complications are the major limitations with a combined rate of 15.9%.

In 41 consecutive patients with 49 stenoses of aorto-coronary venous bypass (ACVB) grafts percutaneous transluminal angioplasty (PTA) was attempted. PTA was successful, i.e., the percent area stenosis was reduced by greater than 20% to less than 70% (quantitative measurement with a precision magnifying lens from two orthogonal angiographic views) in 46 stenoses (94%) of 38 patients (93%). In 35 patients (92%) with 42 stenoses control coronary angiography was performed after a mean interval of 189 +/- 186 days. Recurrence, defined as an increase of percent area stenosis to greater than or equal to 70%, was found in nine stenoses (21%) of nine patients (26%). Recurrence correlated with a stenosis length greater than 10 mm before PTA (5/8 vs 4/32 stenoses: p less than 0.01). In recurrent stenoses, the average diameter of the grafted native coronary artery was significantly smaller than in recurrence-free stenoses (1.92 +/- 0.52 mm vs 2.45 +/- 0.50 mm; p less than 0.01). Clinical data were collected from all 38 patients with successful PTA after an average of 30 +/- 17 months following PTA. In this interval, 11 patients had undergone re-angioplasty and eight patients were re-operated; in addition, there were three cardiac deaths. In the 27 surviving patients without re-operation (71%), angina pectoris had improved from a mean of 3.0 +/- 0.7 before PTA to 1.8 +/- 1.0 (CCS-classification) (p less than 0.001). In 19 of the 27 patients (70%) the exercise stress test was negative, in contrast to only three patients (11%) before PTA. Thus, in the majority of patients PTA of ACVB-graft stenoses improves quality of life.(ABSTRACT TRUNCATED AT 250 WORDS)

36 patients with 68 aorto-coronary venous bypass grafts (45 of which were angiographically patent) were examined via DSA (DV12V, serial mode, Philips) and angiography. Imaging was triggered via R waves, and effected in RAO 30 degrees, LAO 60 degrees, and AP projection. 63 of the 68 grafts were correctly detected (92.7%). Two anterior interventricular branch grafts (RIVA = ramus interventricularis anterior) were not visualised via DSA (95.6% sensitivity). One graft each to the RIVA, to the right coronary artery (RCA), and to the posterior branch of the lateral cutaneous branches of intercostal arteries (PLA), were falsely found to be patent (87% specificity). Grafts were visualised in full length. In some cases morphological changes of the walls were also visible.

In 173 women less than 50 years of age with myocardial infarction, angiographic evidence of coronary sclerosis was observed in only 108 (62%). Completely normal coronary arteries were found in 15 patients (9%) and in 50 patients (29%) an isolated poorly delineated stenosis was found in the presence of otherwise completely normal coronary arteries. Of the 65 patients with myocardial infarction but without typical coronary sclerosis, 47 (72%) were taking oral contraceptives at the time of infarction. In 60% of the oral contraceptive users with infarction, angiographically, there was no evidence of typical coronary sclerosis. With the exception of cigarette smoking, the number of atherogenic risk factors in these patients was low such that myocardial infarction during treatment with oral contraceptives may possibly represent a separate disease entity distinguishable from coronary sclerosis. In support of this, in some cases, repeat angiography demonstrated spontaneous regression of the isolated stenosis. Etiologically, possible thromboembolic vascular occlusion has been assumed. In women in the premenopausal years, coronary sclerosis is uncommon and usually associated with a substantial number of atherogenic risk factors. In this case, 29% of the women had used oral contraceptives, the causal role of which remains uncertain. Even though oral contraceptive use is associated with a higher risk of myocardial infarction, apparently, it cannot be regarded as a typical atherogenic risk factor.

The incidence of ectopic coronary ostia location was investigated in coronary angiograms of 5350 adult patients without associated congenital heart disease. Ectopic coronary origin from the right coronary sinus was observed more than twice as frequently than ectopias from the left coronary sinus. The most common variation (0.7% of all patients) was the origin of the left circumflex branch from the right coronary sinus. Praeoperative knowledge and angiographic demonstration of ectopic coronary arteries is essential in order to avoid damage of these vessels during prosthetic valvular surgery or by aortotomy, to achieve complete revascularization in bypass surgery, and to prevent complications during intraoperative coronary perfusion.

In 48 patients undergoing diagnostic coronary angiography changes of mean diameters of angiographically "normal" coronary segments after intracoronary injections of diatrizoate 76% or iopromide 370 performed in different intervals, were analyzed with a computer-assisted contour detection system (CAAS). Four study protocols were applied, differing in respect to the type of contrast medium administered and/or to the timing of the reference- and control-angiograms in the course of diagnostic coronary angiography. Coronary angiograms in identical projections were performed before (= reference) and directly after (1. control = C1) diagnostic angiography of the left coronary artery by injection of either diatrizoate 76% (group 1, 10 patients) or iopromide 370 (group II, 11 patients). Additional coronary angiograms were performed 1, 3, 6, and 10 min after C1. During diagnostic angiography in either group about eight dye injections were performed in about seven min. With diatrizoate 76% a significant coronary dilation averaging 18.9 +/- 6.7% (p less than 0.001) was observed at C1, depending on the number of diagnostic dye injections performed per min (mean 1.2 +/- 0.3) and on the interval between the last diagnostic injection and C1 (mean 73 +/- 35 s). Coronary dilation persisted up to the sixth minute (6.2 +/- 4.6%, p less than 0.01). With iopromide 370 a small but significant coronary dilation was observed merely at C1 (5.8 +/- 4.3%, p less than 0.05). In two other studies coronary angiograms were performed in identical projections immediately following complete diagnostic coronary angiography (reference) and in addition after 3, 4, 5, 6, 10, and 20 min (group III, 18 patients) and after 10, 20, and 30 min, respectively (group IV, 9 patients) by administration of diatrizoate 76% as the only contrast medium. Short injection intervals (1 min) resulted in a mild coronary dilation (mean up to 2.4 +/- 4.1% compared to reference; p less than 0.05), longer intervals (3-10 min) resulted in a marked diameter reduction (averaging up to -9.7 +/- 9%; p less than 0.05), probably a consequence of the return of coronary vasomotor tone to baseline levels. These results suggest that in quantitative coronary angiographic studies (e.g., testing coronary vasomotility) non-ionic contrast media should preferably be applied, and adequate injection intervals (greater than 2 min) are mandatory. In intervention- and follow-up studies based on repeated coronary angiograms dye-induced changes of coronary vasomotor tone can be avoided by premedication with vasodilating drugs, e.g. nitrates, and/or calcium antagonists.

The characteristics of progressive coronary artery disease as judged from sequential angiography were quantitatively analysed in 19 patients with stable angina in whom coronary angiograms were repeated after 64-104 months (average 76.5 months). The diameters of at most 15 corresponding segments were measured with a vernier caliper (accuracy: 0.05 mm) at identical sites and in the same projections. Considering the error in measurement (less than 10%) and spontaneous changes in smooth muscle tone only a diameter decrease of greater than 20% and/or every transition to an occlusion were recorded as progression. The progression over a 6-year interval was predominately characterized by: A large amount of total occlusions (61% of all progressive stenoses), relatively independent of the initial degree of stenosis. A large amount of newly developed obstructions which are more severe in coronary arteries already segmentally diseased at the onset, indicating a diffuse intramural disease of the entire vessel. A different pattern of progression in the 3 main coronary arteries. No influence of risk factors on natural history.

A dual channel long-term-Ecg monitoring system was used to investigate arrhythmias in 90 patients undergoing diagnostic coronary arteriography. There was no significant difference of ventricular arrhythmias during an observation period of 10 hours before and after cardiac catheterization. The incidence of ventricular premature beats (VPB) was significantly higher in coronary patients than in normal controls (normal coronary arteries and normal ventriculograms) or in a group of 24 healthy soldiers. In patients with coronary artery disease (CAD) the incidence of VPB's was 82 %. There was, however, no significant correlation between the severity of CAD and the number of VPB's although patients with 3-vessel disease showed a tendency to produce more extopic beats. In contrast, patients with generalized or regional left ventricular akinesis (systolic shortening less than 15 %) showed a significantly higher number of VPB's than patients with normal or hypokinetic ventricles. In addition the analysis of qualitative criteria of ventricular arrhythmias with regard to their prognostic significance following Lown's definition showed the same close correlation with ventricular dysfunction. In the group of patients with VPB's of high incidence and prognostic importance cardiac index and ejection fraction was significantly decreased and left ventricular enddiastolic pressure significantly elevated. In conclusion, coronary patients with left ventricular akinesis are prone not only to produce congestive heart failure, but also life-threatening ventricular arrhythmias.

32 patients in an early state of coronary sclerosis were investigated in connection with diagnostic angiography. 8 patients received 2 mg gallopamil (G) and for every 12 patients 0.1 mg/kg propranolol (P), respectively, 0.12 mg/kg Atenolol (A). All medications were injected intravenously over 4 min. The angiograms were repeated in identical projections before (control) as well as 5, 10, 15, and 20 min after G and 2, 4, 6...up to 20 min after P and A. All angiograms were analyzed using a quantitative computerized contour detection system. 10 min after infusion of G 34 measured coronary segments showed a significant (p less than 0.05) medium dilation of 21 +/- 4.3% and after a further 10 min an insignificant increase in coronary diameter was observed up to 25 +/- 4%. After infusion of P and A a distinct vasoconstriction could be seen. Especially P showed a decrease in diameter of almost 25% in small coronary segments (less than 2.0 mm diameter). The dilatative effect of G i.v. seems to be important in the therapy of acute ischemic situations, for instance, for unstable angina, acute myocardial infarction, or during PTCA. The acute coronary vasoconstriction after infusion of P and A should be considered when used in acute ischemic events.

Quantitative in vivo analysis of the vasomotility of epicardial coronary arteries is based on the measurement of changes of the vessel diameters. Vessel contours can be determined with the help of a precision caliper by the investigator or with computer-assisted geometrical analysis systems applying a contour detection algorithm; the variability of the results from repeated coronary diameter measurements in the identical film frame is comparably low with all systems (less than or equal to 0.12 mm standard deviation). When investigating the influence of an intervention on coronary vasomotility the variability of the measurements can only be kept low by careful standardization of the entire method. Repeated coronary angiograms are performed in identical angiographic projections (mono- or biplane) with standardization of the inspiratory status of the patient and of the rate of contrast material injection (automatic injection pump). For quantitative analysis all coronary segments with a diameter greater than 1 mm which are clearly outlined, free from overlaps, and mainly run parallel to the image plane, are selected by the investigator in preferably end-diastolic cineframes. Whereas with a caliper and with most of the semi-automatic edge detection systems the segment diameter can only be measured at particular sites defined by the investigator, few systems are able to analyze and average the diameter over the entire segment length. The variability of measurements of the minimal diameters of coronary stenoses in different cine frames is particularly high; therefore, only distinct changes of this parameter (e.g. with the CAAS-system greater than 0.24 mm) may be considered significant.(ABSTRACT TRUNCATED AT 250 WORDS)

The natural history of coronary artery disease has to be studied by comparing coronary angiograms of the same patient taken at different times. However, conclusions from repeated angiographic studies are fraught with substantial errors mainly because of: 1. patients selection, 2. variable time interval and 3. technical pitfalls. Despite this bias published interval studies demonstrate that coronary atherosclerosis predominantly is a progressive disease: after 2-3 years 50% to 60%, after 3-4 years 60% to 70% and after 5 years more than 80% of patients demonstrate progressive coronary artery disease at angiography. In addition, quantitative evaluation of coronary angiograms reveals that progression of coronary artery disease: 1. has a variable pattern and pace in each coronary artery and 2. predominantly involves initially normal coronary artery segments. From all clinical and angiographic parameters under scrutiny progressive coronary artery disease is significantly correlated to: abnormal lipid levels at the time of the first angiogram, a period of unstable angina pectoris, interval myocardial infarction and initial severity of coronary artery obstruction. It has to be emphasized, however, that in the individual patient the speed of progression is highly variably supporting the concept of different underlying pathophysiological mechanisms (primary/secondary progression). Regression or coronary stenosis is a rare phenomenon which may occur spontaneously and is anecdotally reported in patients after vigorous treatment of severe hyperlipoproteinemia.

A normal coronary arteriogram after transmural myocardial infarction is a well-recognised phenomenon, but the pathophysiology remains unclear in most cases. A possible aetiological role of oral contraceptives is suggested by the occurrence of unequivocal myocardial infarction with normal or near normal coronary arteries in 4 young women who had been taking oral contraceptives. While the cause-effect relation of coronary thrombosis and myocardial infarction remains controversial in patients with coronary atherosclerosis, a primary occlusion of macroscopically normal coronary arteries by cellular elements of blood appears possible in these cases. The action of contraceptives, the, would be analogous to their thrombogenic effect in peripheral veins and cerebral arteries. Absence of atherosclerotic lesions in these patients favours spontaneous thrombolysis and restoration of normal vessel patency in many of these cases. Myocardial blood flow in the region of the damaged left ventricular wall remains low in spite of normal coronary arteries. Reduced perfusion in infarcted areas is assumed to be the consequence of structural and functional alterations at precapillary and capillary level rather than an effect of obstructive coronary disease.

This report concerns a special aspect of coronary angioplasty and contains the combined Frankfurt and Hannover experience in follow-up coronary angiography performed on average 3 months after PTCA. It is based on 71 patients, of whom 54 were studied in Frankfurt by Prof. Kaltenbach and Prof. Kober and 17 in Hannover.

Coronary and left ventricular angiography repeated after an interval of 19 months in 84 patients showed progression of coronary sclerosis in 42 and of ventricular lesions in 7. No relation between the morphology and seriousness of the initial coronary lesions and their progression was noted. No significant differences were observed between patients with and without progression as far as the clinical data and risk factors (angina pectoris, prior myocardial infarct, cholesterol, arterial hypertension, and diabetes) were concerned, though there was a significantly higher percentage in obese subjects.