Assessing coronary stenosis. Quantitative coronary angiography versus visual estimation from cine-film or pharmacological stress perfusion images

Visual judgment of stenosis severity from cine-film or single-photonemission computed tomographic dipyrida-mole perfusion imageswas compared to assessment of stenosis severity as measuredwith digital quantitative coronary angiography. Thirty patientswith angiographically verified single-vessel disease underwentdipyridamole thallium stress testing within 90 days of angiography. RESULTS: A percent diameter stenosis of 50%, a percent area stenosisof 75% and a stenotic flow reserve of <3·75 measuredby quantitative coronary angiography (CMS, version 1·1,Medis Inc.) corresponded to haemodynamically significant stenosisas evaluated by visual estimates from cine-film or perfusionimages. Quantitative coronary angiography percent diameter stenosis(51·2% ± 12·6%) correlated closely (r=0·74)but underestimated significantly visual assessment of stenosisseverity from cine-film (69·3% ±21·2% p=0·0001).However, quantitative coronary angiography percent area stenosis(74·7% ± 11·7%) more closely reflectedvisual estimates from cine-film (P=0·19). Quantitativecoronary angiography stenotic flow reserve showed the highestpositive and negative predictive value regarding visual estimatesfrom cine-film (88%, 86%) or perfusion images (88% 64%) followedby percent diameter stenosis (86% 75% 86% 56%) and percent areastenosis (87% 80% 87% 60%), respectively. CONCLUSION: Evaluation of coronary lesions by quantitative coronary angiographycorresponds closely with visual estimates from cine-film andhaemodynamic significance as evaluated by dipyridamole perfusionimages. (Eur Heart J 1996; 17: 1167–1174)     

Clinical utility of two-dimensional magnetic resonance angiography in detecting coronary artery disease

AIMS: The accuracy of magnetic resonance angiography in detectingproximal coronary artery stenoses is unclear. We postulatedthat fast magnetic resonance angiography is capable of (1) imagingproximal coronary arteries, and (2) detecting stenoses of 50%of their luminal diameter. METHODS AND RESULTS: Thirty-five patients, referred for analysis of angina pectoris,underwent both conventional angiography and magnetic resonanceangiography of coronary arteries. A fast k-space segmented gradient-echotechnique was used during breath-holds. Two observers, blindedto the results of conventional angiography, independently analysedthe magnetic resonance studies for (1) length of visualizedsegments, and (2) presence of signal voids indicative of stenoses.From 140 proximal arteries, 15 (11%) were excluded because ofincomplete imaging or degraded image quality. Mean length ofthe visualized segments was 9±4 mm for the left main,62±16 mm for the left anterior descending, 21±9mm for the left circumflex and 89±32 mm for the rightcoronary artery. Sensitivity for detecting 50% luminal diameterstenoses was 0·00 for the left circumflex, 0·53for the left anterior descending coronary artery, 0·71for the RCA and 1·00 for the left main artery. Specificityvaried from 0·73 for the left anterior descending coronaryartery to 0·96 for the left circumflex. Inter-observeragreement was 0·90. CONCLUSION: Thus, segmented magnetic resonance angiography is capable ofnon-invasive imaging of proximal coronary anatomy. Its goodaccuracy in detecting left main coronary artery disease, intermediateaccuracy in detecting right coronary artery and left anteriordescending coronary artery stenoses, and low accuracy in detectingleft circumflex lesions fit within a range of sensitivitiesand specificities found by others. Further technical advancesare necessary to make the technique clinically robust.     

Angioscopic evaluation of prolonged vs standard balloon inflations during coronary angioplasty: A randomized study

To study the immediate effects of prolonged total balloon inflationduring PTCA, 41 patients (44 lesions) with chronic-stable anginawere randomized for prolonged sequential inflations (three tofive inflations of 3 to 5 min each, for a total duration of 12 min, group 1, n=20 lesions) or ‘standard’ sequentialinflations (three to five inflations of 1 min each, for a totalduration of 3 min, group 2, n-24 lesions). The mean durationof total balloon inflation time was 958 ± 129 s in group1 vs 205 ±46 s in group 2. Results of angioplasty wereassessed on both angiography and percutaneous transluminal coronaryangioscopy performed immediately after the procedure. High qualityimaging of the coronary lumen and lesion morphology was possibleon angioscopy in all patients without any complications. Post-PTCAangiographic percent diameter stenosis was significantly lessin group 1 compared to group 2: 26 ± 10% vs 36 ±8% (P<0.05). On angioscopy, flaps were seen in 16 patientsin group 2, but in only six in group 1 (P<0.02). There wasno difference in the incidence of thrombi on angioscopy betweenthe two groups (group 1: nine cases, group 2: 10 cases). Sensitivityof angiographic detection of flaps and thrombi was poor: 10%and 12% respectively. One patient in each group developed alongitudinal dissection, detected on both angiography and angioscopy. Conclusions: (1) prolonged sequential balloon inflations leadto less residual luminal stenosis after PTCA, with a decreasedincidence of intimal flaps in comparison with standard inflations.(2) Post-PTCA transluminal coronary angioscopy is safe and offersbetter assessment of luminal effects of PTCA than angiography.     

Nocturnal angina in patients with fixed coronary stenosis. Increased coronary vasoconstrictive sensitivity with independence of pacing ischaemic threshold

Atrial pacing and ergonovine tests were performed in 18 consecutivepatients with unstable angina at rest and significant coronaryartery stenosis ( 90% in one vessel in 16 patients). 13 ofthem also had exertional angina. 14 patients presented at leastone positive response (1.0 mm ST-segment shift) to pacing, witha heart rate (144±11 vs 75±13 beats min^–1,P<0.001) and double product (195±26 vs 108±32x 10^–2 P<0.001) significantly higher than during anginaat rest. In the ten patients who presented nocturnal angina,the incidence of positive response to pacing and the pacingischaemic threshold, tested on three different days, were similarto those seen in the remaining patients. In contrast, the ergonovinetest was positive in all patients with nocturnal angina (100%),who required a low dose (0.28±0.2 mg), but it was positivein only four (50%) of those without nocturnal angina, who neededa higher dose (0.55±0.12 mg, P<0.005). Therefore, in patients with severe coronary stenosis and exertionalangina, spontaneous episodes, including nocturnal angina, arenot related to increases in heart rate. The increased coronaryvasoconstrictive sensitivity found in these patients, particularlythose with nocturnal angina, was not dependent on the statusof the coronary reserve, which strongly suggests that changesin coronary tone, focal or diffuse, are involved in the mechanismsof these ischaemic events.     

Effects of amlodipine on transient myocardial ischaemia in patients with a severe coronary condition treated with a beta-blocker

The purpose of this trial was to study the additional anti-ischaemiceffects of amlodipine in coronary patients with ambulant ischaemiadespite beta-blocker therapy. Beta-blockers are the most effectivedrug therapy for reducing the frequency and duration of ambulatoryischaemic episodes. However, the therapeutic advantage of combinedcalcium antagonist-beta-blocker treatment remains questionable. Three hundred and thirteen patients with documented coronaryartery disease, a positive exercise test within 6 months beforeentry and background beta-blocker therapy, were screened. Inclusioncriteria (4 episodes of transient ST segment depression of 1·0 mm and/or 20 min of ischaemia) were demonstratedin a 48 h ECG during the placebo run-in period in 84 (25%) ofthe patients. Eighty-nine percent of the ischaemic episodeswere silent. The eligible patients were then randomized in a2-week, double-blind, parallel group study comparing placeboto amlodipune 10 mg daily added to the beta-blocker. The anti-ischaemicefficacy of the combination therapy was assessed by 48 h ECGmonitoring and exercise tests. Compared to placebo, amlodipine did not significantly reduceeither the frequency (3·7±4·3 vs 4±4·8episodes in the amlodipune group) or the duration of ambulatoryischaemia (mean duration: 43·9±57·1 vs39·6±65·7 min, total duration 3·1±6·7vs 2·8±6·1 h). Exercise-induced ST segmentdepression tended to decrease with amlodipine (58% vs 73% inthe placebo group) and the ischaemia-free workload capacitywas increased (+1·7 stage vs 0·7 stage in theplacebo group, P=0·08). These results suggest that 2 weeks treatment with amlodipinemay not provide any additional anti-ischaemic benefit in patientswith ambulant ischaemia resistant to a beta-blocker therapy.     

Comparison between regional myocardial perfusion reserve and coronary flow reserve in the canine heart

Diameter stenosis and flow reserve are indices of morphologicaland functional severity of coronary artery stenosis. Flow reservecan be determined at coronary arterial or at myocardial level.In the presence of functional collateral circulation, coronaryflow reserve and myocardial perfusion reserve may differ. We studied coronary flow, coronary flow reserve and myocardialperfusion reserve in an open chest dog model with intact collateralcirculation, before and after induction of coronary artery stenosis.Coronary flow was determined with perivascular ultrasonic flowprobes and myocardial perfusion reserve from digital angiographicimages, in the stenotic as well as the adjacent non-stenoticcoronary arteries. Before induction of a stenosis, a significant correlation existedbetween coronary flow reserve and myocardial perfusion reserveof the left anterior descending (r=0·59; P<0·005)and the left circumflex arteries (r=0·84, P<0·005).In stenotic arteries, coronary flow reserve and myocardial perfusionreserve decreased significantly (P<0·005), but inthe adjacent non-stenotic arteries coronary flow reserve wasnot affected Myocardial perfusion reserve in the non-stenoticadjacent left anterior descending artery decreased significantly(P<0·05) and no correlation was found between coronaryflow reserve and myocardial perfusion reserve, whereas in theadjacent non-stenotic left circumflex artery there was no statisticallysignificant decrease (4·1 ± 1·6 3·5± 1·4) but there was a good correlation betweencoronary flow reserve and myocardial perfusion reserve (r=0·85;P<0·005). This study demonstrates that, in the presence of a stenosisand functioning collateral circulation, coronary flow reserveis not a reliable predictor of myocardial perfusion reserve;both parameters provide mutually complementary information.     

Lifestyle and risk factor management and use of drug therapies in coronary patients from 15 countries. Principal results from EUROASPIRE II Euro Heart Survey Programme

Aims The principal aim of the second EUROASPIRE survey was todetermine in patients with established coronary heart diseasewhether the Joint European Societies' recommendations on coronaryprevention are being followed in clinical practice. Methods This survey was undertaken in 1999–2000 in 15European countries: Belgium, Czech Republic, Finland, France,Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Poland,Slovenia, Sweden, Spain and the U.K., in selected geographicalareas and 47 centres. Consecutive patients, men and women 70years were identified retrospectively with the following diagnoses:coronary artery bypass graft, percutaneous transluminal coronaryangioplasty, acute myocardial infarction and myocardial ischaemia.Data collection was based on a review of medical records andinterview and risk assessment at least 6 months after hospitaladmission. Results 8181 medical records (25% women) were reviewed and 5556patients (adjusted participation rate 76%) interviewed. Recordingof risk factor history and risk factor measurement in hospitalnotes was incomplete, particularly for discharge documents.At interview (median time 1·4 years after hospital discharge),21% of patients smoked cigarettes, 31% were obese, 50% had raisedblood pressure (systolic blood pressure 140mmHg and/or diastolicblood pressure 90mmHg), 58% had elevated serum total cholesterol(total cholesterol 5mmol.l^–1) and 20% reported a medicalhistory of diabetes. Glucose control in these diabetic patientswas poor with 87% having plasma glucose >6·0mmol.l^–1and72% 7·0mmol.l^–1. Among the patients interviewedthe use of prophylactic drug therapies on admission, at dischargeand at interview was as follows: aspirin or other antiplateletsdrugs 47%, 90% and 86%; beta-blockers 44%, 66% and 63%; ACEinhibitors 24%, 38% and 38%; and lipid-lowering drugs 26%, 43%and 61%, respectively. With the exception of antiplatelet drugs,wide variations in the use of prophylactic drug therapies existbetween countries. Conclusions This European survey of coronary patients showsa high prevalence of unhealthy lifestyles, modifiable risk factorsand inadequate use of drug therapies to achieve blood pressureand lipid goals. There is considerable potential throughoutEurope to raise the standard of preventive cardiology throughmore effective lifestyle intervention, control of other riskfactors and optimal use of prophylactic drug therapies in orderto reduce coronary morbidity and mortality.     

Evolution of coronary atherosclerosis in patients with mild coronary artery disease studied by serial quantitative coronary angiography at 2 and 4 years follow-up

AIMS: Angiographic studies on the natural course of both focal anddiffuse coronary atherosclerosis have not been performed before,but can both be assessed by quantitative coronary angiography.The objective of this study was to describe the natural courseof focal and diffuse coronary atherosclerosis over time. METHODS AND RESULTS: In 129 patients with mild coronary artery disease, but not onlipid-lowering medication, three coronary angiograms were madeeach 2 years apart. Nine hundred and sixty five angiographicallydiseased and non-diseased segments were analysed by quantitativecoronary angiography. Mean lumen diameter and minimal lumendiameter were used as measures of diffuse and focal coronaryatherosclerosis. Mean lumen diameter and minimum lumen diameter decreased by0·02 and 0·03 mm per year. The rate of progresssionwas similar in the angiographically non-diseased, as in themildly and moderately diseased segments. Progression of diffusecoronary atherosclerosis was largest in severely stenosed lesions(percentage diameter stenosis 50%) and in the right coronaryartery with a loss of 0·19 mm and 0·16 mm in meanlumen diameter. Progression of focal disease was most prominentin new and mild lesions and the right coronary artery, witha decrease in minimum lumen diameter of 0·34 mm and 0·22mm. In most subgroups, progression occurred gradually over time.On a per segment level, progression and the occurrence of newlesions occurred in 4·4% and 4·2%. Regressionand disappearance of a lesions was found in 2·3% and1·9%. On a per patient level, 36% were progressors, 12%had a mixed response, 36% were stable, and 16% were regressors. CONCLUSION: Diffuse and focal coronary atherosclerosis progressed at thesame rate in the first and second 2 years in stenosed and non-stenosedsegments. The rate of coronary atherosclerosis progression wassmall, but was higher for focal than for diffuse disease. Aminority of lesions progressed and spontaneous regression wasrare.     

Lipoprotein(a) as a risk predictor for cardiac mortality in patients with acute coronary syndromes

Aims Raised lipoprotein(a) concentrations are considered to be arisk factor for atherothrombotic diseases. We examined whetherbaseline concentrations were a risk factor for an adverse outcomein patients admitted with acute coronary syndromes. Methods and Results Five hundred and nineteen patients admitted with suspected acutecoronary syndromes were studied and followed prospectively fora median of 3 years. The prognostic significance of a baselinelipoprotein(a) concentration of 30mg.dl^–1or lower forsubsequent cardiac death was assessed in patients with myocardialinfarction (266) and unstable angina (197) and compared withother variables in regression models. In patients with myocardialinfarction, a baseline lipoprotein(a) concentration of 30mg.dl^–1wasassociated with a 62% increase in subsequent cardiac death comparedto the lower concentration group (29·8% vs 18·6%,Log rankP=0·04). In a multivariate regression model abaseline lipoprotein(a) concentration of 30mg.dl^–1retainedits significance as an independent predictor of cardiac death(P=0·037). In patients with unstable angina, baselineconcentrations of 7·9mg.dl^–1were found to be significantpredictors of cardiac death in univariate (P=0·021) andmultivariate (P=0·035) regression models. Conclusion Baseline lipoprotein(a) concentrations in patients admittedwith acute coronary syndromes are associated with an increasedrisk of cardiac death. For patients with myocardial infarctiona concentration of 30mg.dl^–1appears appropriate as a riskdiscriminator; for patients admitted with unstable angina, however,much lower concentrations of lipoprotein(a) appear to be prognosticallyimportant.     

Time domain analysis of the signal averaged electrocardiogram in patients with a conduction defect or a bundle branch block

Doubts have been expressed about the clinical usefulness oftime domain analysis of the signal averaged electrocardiogramin patients with prolonged QRS complex duration. We studied147 patients using a signal averaged ECG (40–250 Hz) whoseQRS complex was longer than 100 ms. A baseline electrophysiologystudy was also performed in 128 of these patients. Seventy-sevenpatients had a minor (QRS <120 and >100 ms) conductiondefect. Thirty-seven of these 77 had either induced or spontaneoussustained ventricular tachycardia (group I) and 40 had no sustainedventricular tachycardia (group II). Seventy patients had a major(QRS120 and >100 ms) conduction defect, 44 of whom had sustainedventricular tachycardia (group A). The remaining 26 withoutthis condition formed Group B. Group I compared to group IIpatients had a longer filtered QRS duration (120·8 ±14 vs 104·5 ± 9·5 ms, P<0·001),a longer low amplitude signal duration (41 ± 12·1vs 31 ± 12·6 ms, P<0·0001) and a lowerroot mean square of the last 40 ms of the filtered QRS complex(27 ± 29·8 vs 35 ± 25·3 µV,P=ns). Group A compared to group B had a longer filtered QRSduration (157·7±20·2 vs 140·7±15·7 ms, P<0·001), a longer low amplitude signalduration (57·3 ±24·9 vs 37·8 ±20·3 ms P<0·001) and a lower root mean squareof the last 40 ms of the filtered QRS complex (14·3 ±11·2 vs 22·0 ± 10·5 1 P<0·01).Using conventional late potential criteria, the sensitivityand specificity of the signal averaged ECG for the detectionof sustained ventricular tachycardia patients with a minor conductiondefect were 89% and 75%, respectively. The same criteria appliedto patients with a major conduction defect were sensitive (sensitivity:87%) but non-specific (specificity: 50%). However, by usingmodified late potential criteria, such as the presence of twoof any of the following three signal averaged parameters: filteredQRS duration 145 ms, low amplitude signal duration 50 ms,root mean square of the last 40 ms of the filtered QRS complex17·5µV, we derived a non-optimal but still acceptablecombination of sensitivity (68%) and specificity (73%). We concludethat traditional late potential criteria can be applied in patientswith a minor conduction defect, but modification of these criteriais necessary to derive useful clinical information for riskstratification of patients with a QRS complex duration 120ms.     

Long-term (10 years) prognostic value of a normal thallium-201 myocardial exercise scintigraphy in patients with coronary artery disease documented by angiography

In order to assess the prognostic significance of normal exercisethallium-210 myocardial scintigraphy in patients with documentedcoronary artery disease, we studied the incidence of cardiacdeath and non-fatal myocardial infarction in 69 symptomaticpatients without prior Q wave myocardial infarction, who demonstratedone or more significant coronary lesions (stenosis 70%) on anangiogram performed within 3 months of scintigraphy (Group 1).These patients were compared to a second group of 136 patientswith an abnormal exercise scintigram, defined by the presenceof reversible defect(s) and angiographically proven coronaryartery disease (Group 2), and to a third group of 102 patientswith normal exercise scintigraphy without significant coronarylesions (stenosis 30%) or with normal coronary angiography (Group3). In contrast to coronary lesions observed in Group 2, patientsin Group I presented more frequently with single- vessel disease(83% vs 35%, P>0·0001) and with more distal lesions(55% vs 23%, P>0·0001). Over a mean follow-up periodof 8·6 years, one fatal and eight non-fatal cases ofmyocardial infarction were observed in Group 1. The majorityof patients in Group 1 were treated medically: only 24 (35%)underwent myocardial revascularization, usually by coronaryangioplasty. There was no significant difference in the incidenceof combined major cardiac events (cardiac death, non-fatal myocardialinfarction) in patients with normal exercise scintigraphy, withor without documented coronary artery disease (Groups 1 and3), while the incidence was higher in Group 2. However, whilethe mortality remained very low in Group 1, the incidence ofnon-fatal myocardial infraction was not different from thatof Group 2, where most patients underwent revascularizationprocedures. In conclusion, patients with coronary artery disease and a normalexercise thallium-201 myocardial scintigram usually have mildcoronary lesions (single-vessel disease, distal location) andgood long-term prognosis, with a low incidence of cardiac death.     

Gradient-echo magnetic resonance imaging during incremental dobutamine infusion for the localization of coronary artery stenoses

Dobutamine pharmacological stress testing in conjunction withgradient-echo magnetic resonance imaging (MRI) may be a usefultool for the assessment of haemodynamically significant coronaryartery stenoses. Therefore, 28 patients without previous myocardialinfarction but significant proximal stenoses (70% diameter stenosis)of one or more coronary arteries were selected for dobutamine-MRI.Each patient underwent MRJ at rest and during incremental dobutamineinfusion (5, 10, 15 and 20 µg. kg^–1. min^–1).Additionally, all patients were submitted to exercise stresselectrocardiography (EST). A total of 72 segments per patient obtained from identical shortaxis and transverse tomograms at rest and during dobutamineinfusion were evaluated by two observers. Each segment was gradedas normal, hypokinetic, akinetic or dyskinetic. Dobutamine-MRIwas considered pathological if segmental wall motion deterioratedby at least one grade after dobutamine infusion. For comparisonwith coronary angiography, segmental wall motion gradings wererelated to the respective coronary artery territories. Peakrate-pressure product during steady-state dobutamine infusion(18·493 ± 4·315 mmHg. min^–1) wassignificantly lower (P<0·01) than during EST (21·316± 4·937 mmHg. min^–1). Dobutanine-inducedwall motion abnormalities were observed in 22/26 (85%) MR studiesand 20/26 (77%) patients had a pathological EST. Regional asynergyinduced by dobutamine-MRI occurred in 11/15 (73%) patients withsingle and 11/11 (100%) with multi-vessel disease. Sensitivityand specificity for the detection of a stenosed coronary arterywere 87% and 100% for the left anterior descending, 62% and93% for the left circumflex and 78% and 88% for the right coronaryartery respectively. In conclusion, dobutamine-MRI is a well tolerated, non-exercisedependent test for the detection and localization of hzaemodynamicallysignificant coronary artery stenoses with a diagnostic accuracysimilar to that previously reported for high-dose dipyridamoleMRI but with a better control of stress intensity and duration.     

Effects of percutaneous balloon mitral valvuloplasty and exercise training on the kinetics of recovery oxygen consumption after exercise in patients with mitral stenosis

Aims Kinetics of recovery oxygen consumption after exercise playsan important role in determining exer-cise capacity. This studywas performed to assess the kinetics of recovery oxygen consumptionin mitral stenosis and evaluate the effects of percutaneousballoon mitral valvuloplasty and exercise training on the kinetics. Methods and Results Thirty patients with mitral stenosis (valve area 1·0cm²)and same sized age- and size-matched healthy volunteers wereincluded for this study. All subjects performed maximal uprightgraded bicycle exercise. Thirty consecutive patients who underwentsuccessful percutaneous balloon mitral valvuloplasty (valvearea 1·5cm²and mitral regurgitation grade 2), were randomizedto an exercise training group or non-training group. The exercisegroup performed daily exercise training for 3 months. Half-recoverytime of peak oxygen consumption was significantly delayed inmitral stenosis as compared to normal subjects (120±42svs 59±5,P<0·01). Peak oxygen consumption (ml.min^–1.kg^–1)was significantly increased in both the training (16·8±4·9to 25·3±6·9) and non-training groups (16·3±5·1to 19·6±6·0) 3 months after percutaneousballoon mitral valvuloplasty. Half-recovery time of peak oxygenconsumption was significantly shortened in the training group(124±39 to 76±13,P<0·01), but not inthe non-training group (114±46 to 109±44s,P=0·12)at 3 months follow-up. The degrees of symptomatic improvementafter percutaneous balloon mitral valvuloplasty were more closelycorrelated with the changes of the half-recovery time of peakoxygen consumption than those of peak oxygen consumption. Conclusion Kinetics of recovery oxygen consumption was markedly delayedin mitral stenosis, which was improved after exercise trainingbut not after percutaneous balloon mitral valvuloplasty alone.These results suggest that adjunctive exercise training maybe useful for improvement of recovery kinetics and subjectivesymptoms after percutaneous balloon mitral valvuloplasty.     

Assessment of coronary artery stenosis during PTCA by measurement of the trans-stenotic pressure gradient: Comparison with quantitative coronary angiography

A fibreoptic pressure sensor mounted on an 0 018 inch guidewire(Pressure Guide®, RadiMedical Systems, Uppsala, Sweden)was used to measure the trans-stenotic pressure gradient in20 patients admitted for percutaneous transluminal coronaryangioplasty (PTCA) of a single, discrete stenosis. Pressuremeasurements were made both at rest and during maximal vasodilatationinduced by intracoronary injection of papaverine. From the ratioof distal coronary pressure divided by the proximal pressure,the relative coronary flow reserve was calculated. The aim ofthe study was to compare the different pressure-derived parametersby correlating them to stenosis geometry estimated by quantitativecoronary angiography. There was a moderate correlation betweenbaseline pressure gradient and percent area stenosi r= 0.64,P<0.001 and minimal cross-sectional area; r= 0.45, P<0005.A higher correlation was found between hyperaemic pressure gradientand area stenosis (r= 080, P<0001) and minimal cross-sectionalareas, respectively (r= 0.55, P<0 005). The best correlationwas found between relative coronary flow reserve and area stenosis(r= 0.86, P<0.001) and minimal cross-sectional area (r= 0.70,P<0001). In conclusion, pressure measurement using a pressure guidewireis useful as a complement to angiography in evaluation of coronarystenoses during PTCA. Pressures should be measured during maximalvasodilatation. Relative coronary flow reserve calculated fromthe pressure measurements provides additional information aboutthe fraction of normal maximal flow possible in the presenceof a stenosis.     

EUROASPIRE: A European Society of Cardiology survey of secondary prevention of coronary heart disease: Principal results

BACKGROUND: The three major European scientific societies in cardiovascularmedicine—the European Society of Cardiology (ESC), theEuropean Atherosclerosis Society and the European Society ofHypertension—published in October 1994 joint recommendationson prevention of coronary heart disease in clinical practice.Patients with established coronary heart disease, or other majoratherosclerotic disease, were deemed to be the top priorityfor prevention. A European survey (EUROASPIRE) was thereforeconducted under the auspices of the ESC to describe currentclinical practice in relation to secondary prevention of coronaryheart disease. AIMS: The aims of EUROASPIRE were (i) to determine whether the majorrisk factors for coronary heart disease are recorded in patientsmedical records; (ii) to measure the modifiable risk factorsand describe their current management following hospitalization,and (ii) to determine whether first degree blood relatives havebeen screened. MEHTODS: The survey was conducted in selected geographical areas andhospitals in nine European countries. Consecutive patients (70 years) were identified retrospectively with the followingdiagnoses: coronary artery bypass grafting, percutaneous transluminalcoronary angioplasty, acute myocardial infarction and acutemyocardial ischaemia without infarction. Data collection wasbased on a retrospective review of hospital medical recordsand a prospective interview and examination of the patients. RESULTS: 4863 medical records were reviewed of whom 25% were women, and3569 patients were interviewed (adjusted response rate 85%)with an average age of 61 years. Nineteen percent of patientssmoked cigarettes, 25% were overweight (BMI 30 kg. m^–2),53% had raised blood pressure (systolic BP 140 and/or diastolicBP 90 mmHg), 44% had raised total plasma cholesterol (totalcholesterol 5·5 mmol . l^–1) and 18% were diabetic.Reported medication at interview was: antiplatelet drugs 81%,beta-blockers, 54% (58% in post-infarction patients). ACE inhibitors30% (38% in post infarction patients) and lipid lowering drugs32%. Of the patients receiving blood pressure lowering drugs(not always prescribed for the treatment of hypertension) 50%had a systolic BP <140 mmHg and 21% <160 mmHg, and ofthose receiving lipid lowering drugs, 49% had plasma total cholesterol<5·5 mmol. l^–1 and 13% <6·5 mmol.l^–1. Thirty-seven percent of patients had a family historyof premature coronary heart disease in a first-degree bloodrelative, but only 21% of patients reported being advised tohave their relatives screened for coronary risk factors. CONCLUSIONS: This European survey has demonstrated a high prevalence of modifiablerisk factors in coronary heart disease patients. There is considerablepotential for cardiologists and physicians to further reducecoronary heart disease morbidity and mortality and improve patientschances of survival     

Effects of amlodipine on transient myocardial ischaemia in patients with a severe coronary condition treated with a beta-blocker

The purpose of this trial was to study the additional anti-ischaemiceffects of amlodipine in coronary patients with ambulant ischaemiadespite beta-blocker therapy. Beta-blockers are the most effectivedrug therapy for reducing the frequency and duration of ambulatoryischaemic episodes. However, the therapeutic advantage of combinedcalcium antagonist-beta-blocker treatment remains questionable. Three hundred and thirteen patients with documented coronaryartery disease, a positive exercise test within 6 months beforeentry and background beta-blocker therapy, were screened. Inclusioncriteria (4 episodes of transient ST segment depression of 1.0 mm and/or 20 min of ischaemia) were demonstrated in a 48h ECG during the placebo run-in period in 84 (25%) of the patients.Eighty-nine percent of the ischaemic episodes were silent. Theeligible patients were then randomized in a 2-week, double-blind,parallel group study comparing placebo to amlodipune 10 mg dailyadded to the beta-blocker. The anti-ischaemic efficacy of thecombination therapy was assessed by 48 h ECG monitoring andexercise tests. Compared to placebo, amlodipine did not significantly reduceeither the frequency (3.7±4.3 vs 4±4.8 episodesin the amlodipune group) or the duration of ambulatory ischaemia(mean duration: 43.9±57.1 vs 39.6±65.7 min, totalduration 3.1±6.7 vs 2.8±6.1 h). Exercise-inducedST segment depression tended to decrease with amlodipine (58%vs 73% in the placebo group) and the ischaemia-free workloadcapacity was increased (+1.7 stage vs 0.7 stage in the placebogroup, P=0.08). These results suggest that 2 weeks treatment with amlodipinemay not provide any additional anti-ischaemic benefit in patientswith ambulant ischaemia resistant to a beta-blocker therapy.     

Normal coronary flow reserve in patients with mitral valve prolapse, a positive exercise test and normal coronary arteries

We studied 12 patients (eight females and four males), ages30–46 years, with echocardiographically documented mitralvalve prolapse and clinical suspicion of coronary artery disease,based on a history of chest pain (five patients), angina-likepain (three patients), a positive exercise stress electrocardiogram(12 patients) and a focally positive thallium-201 stress perfusionscan (three patients), who were referred for cardiac catheterizationand found to have normal coronary arteries. Ten patients withoutevidence of heart disease served as controls. In all mitralvalve prolapse patients, coronary flow velocity reserve wasdetermined successively in the left anterior descending, leftcircumflex and right coronary arteries as the ratio of the maximun(after intracoronary papaverine) to the resting mean coronaryflow velocity. Coronary flow reserve values were fairly similarin the mitral valve prolapse and control patients; all 12 mitralvalve prolapse patients had normal coronary flow reserve (3·5)in all three coronary arteries with no significant differencesamong the arteries tested Mean values ± 1 standard deviationof the coronary flow reserve (mitral valve prolapse vs controlpatients) were 4·7 ± 0·5 vs 4·6± 0·6 for the left anterior descending, 4·6± 0·4 vs 4·6 ± 0·3 for theleft circumflex and 4· ± 0·4 vs 4·4± 0·5 for the right coronary artery (all P=non-significant).The subsets of mitral valve prolapse patients with differentclinical ‘ischaemic’ manifestations were similarin terms of the calculated coronary flow reserve in all threemajor epicardial coronary arteries. In conclusion, this study demonstrated that an inadequate regionalcoronary flow reserve does not account for the clinical manifestationsof myocardial ischaemia and positive exercise tests in patientswith mitral valve prolapse and normal coronary arteries.     

Antihypertensive treatment with felodipine but not with a diuretic reduces episodes of myocardial ischaemia in elderly patients with hypertension

Episodes of transient myocardial ischaemia can frequently beobserved in hypertensive patients. To assess the effects ofantihypertensive treatment with the calcium antagonist felodipineor the diuretic combination hydrochlorothiazidel triamtereneon episodes of ischaemic-type ST-segment depression (ST-D),simultaneous ambulatory electrocardio-graphic and blood pressure(BP) monitoring was performed in 42 elderly hypertensives withoutmanifest coronary artery disease. All patients (mean age 79± 6 years, office BP 160/95 mmHg) were evaluated offany antihypertensive or anti-ischaemic therapy and after 3 monthstreatment with either felodipine or the diuretic (randomized,double-blind study) for episodes of significant ST-D (0.1 mV,duration 1 min, interval 1 min). The reduction in office BPand daytime ambulatory BP was similar for both agents, as wasa significant reduction in the heart rate x systolic BP product(DP) over 24 h (felodipine: 12 441 ±2076 vs 11 643 ±1953 mmHg. min^–1; P=0.048; diuretic: 12 366 ± 2782vs 11 062 ± 2012 mmHg. min^–1; P=0.003). While felodipinesignificantly decreased the total number of ST-D (from 40 tosix episodes; P=0.03), the total number of ST-D remained unchangedwith the diuretic (non-significant increase from 31 to 45 episodes;P=0.24). The same trend was observed for the number of patientswith ST-D. The ischaemic threshold, defined as DP at the onsetof the episodes of ST-D, increased with felodipine (12 171 ±340vs 13 770 ± 138 mmHg. min^–1) and decreased withthe diuretic (16 210 ±312 vs 14 092 ± 319 mmHg.min^–1). In conclusion, antihypertensive treatment withfelodipine reduces blood pressure and episodes of transientmyocardial ischaemia in elderly hypertensive patients, whilehydrochlorothiazidel triamterene increases these episodes despitea similar BP reduction. Felodipine may influence structuraland functional factors at the coronary micro circulation level.These mechanisms improve coronary blood flow and increase theischaemic threshold.     

Significant coronary restenosis limits the recovery of regional left myocardial dysfunction achieved after successful coronary angioplasty

Impaired regional left ventricular function has been shown toimprove after successful transluminal coronary angioplasty,but there are no data concerning the effect of coronary restenosison this recovery. Therefore, the short- (1 month) and midterm(5.5 months) evolution of systolic regional left ventricularfunction was prospectively investigated in 41 patients undergoingsuccessful coronary angioplasty. In patients with resting hypokineticareas before angioplasty and no restenosis (n=8), regional functionimproved from –6.0±2.9 to –2.9±2.4SD/segment (P<0.01) in the short-term, without further significantchanges at mid-term. Patients with hypokinetic areas and coronaryrestenosis 70% (n = 15) also showed early functional recoveryfrom –5.1 ± 2.2 to –1.4 ± 2.5 SD/segment(P <0.0001) but, in contrast with the other subset of patients,a significant reduction to –3.9±2.3 SD/segment(P<0.0001) was observed at mid-term. In spite of this, regionalfunction was still better than before angioplasty (P <0.01).No significant changes were observed in patients without eitherasynergy or restenosis (n = 16). The small number of cases withoutpreliminary hypokinesis and development of restenosis 70% (n= 2) precluded an analysis of this situation, but a new andsevere hypokinetic defect was recognized in one patient in alater study. We conclude that the improvement in regional myocardialfunction observed early after successful dilation of the culpritvessel is partially lost when significant restenosis develops.     

Angiographic findings and catheterization laboratory events in patients with primary coronary angioplasty or streptokinase therapy for acute myocardial infarction

Background: The purpose of this study was to evaluate catheterizationlaboratory events and angiographic findings in patients randomlyassigned to undergo primary coronary angioplasty or to receiveintravenous streptokinase for acute myocardial infarction. Methods: We analysed angiographic data in 301 patients withacute myocardial infarction, randomly assigned to undergo primarycoronary angioplasty without antecedent thrombolytic therapyor to receive intravenous streptokinase therapy. Follow-up coronaryangiography was preferably performed after 3 months. AII angiogramswere analysed with a quantitative coronary analysis system. Results: Of the 152 patients assigned to angioplasty treatment,140 underwent this procedure with a success rate of 97%. Theresidual diameter stenosis of the infarct-related vessel immediatelyafter angioplasty was 27 ± 15% and there were major eventsin 14% of the patients in the catheterization laboratory. Atfollow-up angiography after a mean interval of 92 days in theangioplasty assigned patients, a diameter stenosis of 35 ±22% was observed in this group. The restenosis rate was 28%and the reocclusion rate 5%. A Thrombolysis in Myocardial Infarction(TIMI) grade 2 flow immediately after angioplasty was predictivefor reocclusion at follow-up (P= 0.001). In the streptokinaseassigned patients (149) the infarct-related vessel was patentat follow-up angiography after a mean of 22 days in 66% of thepatients with a mean residual diameter stenosis of 77 ±20%. Conclusion: Primary coronary angioplasty is a highly effectiveand safe reperfusion modality for patients with acute myocardialinfarction. However, TIMI grade 2 flow through the infarct-relatedvessel immediately after angioplasty is a predictor of reocclusion.