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Since the introduction of coronary CT angiography (CCTA) there has been an enormous growth in the quantity of evidence to support the role of CCTA in the diagnosis of patients with suspected coronary artery disease (CAD). But what is the level of diagnostic accuracy of CCTA today? Have we attained sufficient reliable evidence to fully appreciate the role of CCTA in cardiologic practice? The technical details and potential clinical applications of CCTA have been reported in two recent reviews in ‘Education in Heart ’.1 ,2 In this current state-of-the-art exposition of CCTA for patients with suspected CAD it appears useful to arrange the available evidence according to a hierarchical model of efficacy of diagnostic imaging first described by Fryback and Thornburg in 1991.3 Efficacy is defined as: “the probability of benefit to individuals in a defined population from medical technology (CCTA) applied for a given medical problem under ideal conditions”.3 The model consists of six levels of efficacy: level 1 —technical efficacy; level 2 —diagnostic accuracy efficacy; level 3 —diagnostic thinking accuracy; level 4 —therapeutic efficacy; level 5 —patient outcome efficacy; level 6 —societal efficacy. The goal of the model not only involves the traditional view of the assessment of diagnostic imaging to generate optimal quality images and hence optimal diagnosis, but rather is a comprehensive assessment of patient and societal benefits of CCTA.3 This review is an update of the current position of CCTA in the diagnosis of patients with suspected CAD. The spatial resolution of 64-slice (or more) CCTA in the laboratory setting is 0.3–0.4 mm³ (isotropic spatial resolution allowing undistorted reconstruction of images in any plane), but in the clinical setting this is 0.5–0.6 mm³. The spatial resolution of CCTA is still limited compared to the 0.1–0.2 mm of invasive coronary angiography (ICA). The temporal resolution …

Objective: To evaluate the performance of dual source CT coronary angiography (DSCT-CA) in the detection of in-stent restenosis (>= 50% luminal narrowing) in symptomatic patients referred for conventional angiography (CA). Design/patients: 100 patients (78 males, age 62 (SD 10)) with chest pain were prospectively evaluated after coronary stenting. DSCT-CA was performed before CA. Setting: Many patients undergo coronary artery stenting; availability of a non-invasive modality to detect in-stent restenosis would be desirable. Results: Average heart rate (HR) was 67 (SD 12) (range 46-106) bpm. There were 178 stented lesions. The interval between stenting and inclusion in the study was 35 (SD 41) (range 3-140) months. 39/100 (39%) patients had angiographically proven restenosis. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of DSCT-CA, calculated in all stents, were 94%, 92%, 77% and 98%, respectively. Diagnostic performance at HR,70 bpm (n = 69; mean 58 bpm) was similar to that at HR >= 70 bpm (n = 31; mean 78 bpm); diagnostic performance in single stents (n = 95) was similar to that in overlapping stents and bifurcations (n = 83). In stents >= 3.5 mm (n = 78), sensitivity, specificity, PPV, NPV were 100%; in 3 mm stents (n = 59), sensitivity and NPV were 100%, specificity 97%, PPV 91%; in stents (2.75 mm (n = 41), sensitivity was 84%, specificity 64%, PPV 52%, NPV 90%. Nine stents (2.75 mm were uninterpretable. Specificity of DSCT-CA in stents >= 3.5 mm was significantly higher than in stents (2.75 mm (OR = 6.14; 99%CI: 1.52 to 9.79). Conclusion: DSCT-CA performs well in the detection of in-stent restenosis. Although DSCT-CA leads to frequent false positive findings in smaller stents ((2.75 mm), it reliably rules out in-stent restenosis irrespective of stent size.

Objective: To compare clinical outcome of paclitaxel eluting stents (PES) versus sirolimus eluting stents (SES) for the treatment of acute ST elevation myocardial infarction. Design and patients: The first 136 consecutive patients treated exclusively with PES in the setting of primary percutaneous coronary intervention for acute myocardial infarction in this single centre registry were prospectively clinically assessed at 30 days and one year. They were compared with 186 consecutive patients treated exclusively with SES in the preceding period. Setting: Academic tertiary referral centre. Results: At 30 days, the rate of all cause mortality and reinfarction was similar between groups (6.5% v 6.6% for SES and PES, respectively, p = 1.0). A significant difference in target vessel revascularisation (TVR) was seen in favour of SES (1.1% v 5.1% for PES, p = 0.04). This was driven by stent thrombosis (n = 4), especially in the bifurcation stenting (n = 2). At one year, no significant differences were seen between groups, with no late thrombosis and 1.5% in-stent restenosis (needing TVR) in PES versus no reinterventions in SES (p = 0.2). One year survival free of major adverse cardiac events (MACE) was 90.2% for SES and 85% for PES (p = 0.16). Conclusions: No significant differences were seen in MACE-free survival at one year between SES and PES for the treatment of acute myocardial infarction with very low rates of reintervention for restenosis. Bifurcation stenting in acute myocardial infarction should, if possible, be avoided because of the increased risk of stent thrombosis.

To evaluate the impact of heart rate on the diagnostic accuracy of coronary angiography by multislice spiral computed tomography (MSCT).Prospective observational study.78 patients who underwent both conventional and MSCT coronary angiography for suspicion of de novo coronary artery disease (n=53) or recurrent coronary artery disease after percutaneous intervention (n=25).Tertiary referral centre.Intravenously contrast enhanced MSCT coronary angiography was done during a single breath hold, and ECG synchronised images were reconstructed retrospectively. All coronary segments ofor = 2.0 mm without stents were evaluated by two investigators and compared with quantitative coronary angiography. Patients were classified according to the average heart rate (mean (SD)) into three equally sized groups: group 1, 55.8 (4.1) beats/min; group 2, 66.6 (2.8) beats/min; group 3, 81.7 (8.8) beats/min.Image quality was sufficient for analysis in 78% of the coronary segments in patients in group 1, 73% in group 2, and 54% in group 3 (p0.01). The sensitivity and specificity for detecting significant stenoses (or = 50% lumen reduction) in these assessable segments were: 97% (95% confidence interval (CI) 84% to 100%) and 96% in group 1; 74% (52% to 89%) and 94% in group 2; and 67% (33% to 90%) and 94% in group 3 (p0.05). Accounting for all segments ofor = 2.0 mm, including lesions in non-assessable segments as false negatives, the sensitivity decreased to 82% (28/34 lesions, 95% CI 69% to 91%), 61% (14/23 lesions, 42% to 77%), and 32% (6/19 lesions, 15% to 50%), respectively (p0.01).MSCT allows reliable coronary angiography in patients with low heart rates.

OBJECTIVE: To describe the long term clinical outcome (up to 11 years) after coronary stenting. DESIGN: A single centre observational study encompassing 1000 consecutive patients with a first stent implantation (1560 stents) between 1986 and 1996, who were followed for at least one year with a median follow up of 29 months (range 12-132 months). RESULTS: Up to July 1997 the cumulative incidence of the major adverse cardiac events (MACE) of death, non-fatal acute myocardial infarction, coronary artery bypass grafting, and repeat percutaneous transluminal coronary angioplasty was 8.2%, 12.8%, 13.1%, and 22.4%, respectively. Survival at one, three, and five years was 95%, 91%, and 86%, respectively. Comparison of MACE incidence during the "anticoagulant era" and the "ticlopidine era" revealed significantly improved event free survival with ticlopidine (27% v 13%; p < 0.005). Multivariable analyses showed that ejection fraction < 50% (relative risk (RR) 4. 1), multivessel disease (RR 3.0), diabetes (RR 2.9), implantation in saphenous vein graft (RR 2.1), indication for unstable angina (RR 1. 9), and female sex (RR 1.7) were independent predictors of increased mortality after stenting. Independent predictors of any MACE were multivessel stenting (RR 2.0), implantation in saphenous bypass graft (RR 1.6), diabetes (RR 1.5), anticoagulant treatment (versus ticlopidine and aspirin) (RR 1.5), bailout stenting (RR 1.5), multivessel disease (RR 1.4), and multiple stent implantation (RR 1. 5). CONCLUSIONS: Long term survival and infarct free survival was good, particularly in non-diabetic men with single vessel disease and good ventricular function, who had a single stent implanted in a native coronary artery. A dramatic improvement was observed in event free survival, both early and late, with the replacement of anticoagulation by ticlopidine. This, of course, cannot be separated from improved stent implantation techniques between 1986 and 1995. Ultimately, almost 40% of the patients experienced an adverse cardiac event (mainly repeat intervention) in the long term. New advances in restenosis treatments and in secondary prevention must be directed at this aspect of patient management after stenting.

Coronary imaging is the ultimate challenge. During the last decade there have been great advances in this imaging technique, partly as a result of improved scanner hardware, but more because of advances in microprocessor technology Coronary imaging is the ultimate challenge for any imaging technique. This is because the coronary arteries are small (2–4 mm in diameter) and have a tortuous, complex, three dimensional course and are continuously in motion, except for a short period during mid diastole. During the last decade we have witnessed great advances in cardiac imaging. This was partly as a result of improved scanner hardware, but more because of advances in microprocessor technology, which allow for rapid processing of extremely large quantities of data necessary for the acquisition, post-processing, and construction of hitherto unimaginable, non-invasively obtained images of the coronary lumen and plaque. This raises two important questions. Firstly, has progress in non-invasive coronary imaging techniques gone so far that conventional invasive diagnostic coronary angiography has become redundant? Secondly, are these new imaging techniques capable of detecting which coronary plaque is stable, unstable or vulnerable? Magnetic resonance coronary angiography (MR-CA), electron beam computed tomography (EBCT), and multi-slice computed tomography (MS-CT) have recently emerged as new non-invasive diagnostic techniques that possess the potential to replace conventional diagnostic angiography.1–4 The diagnostic accuracy to detect a significant coronary stenosis is presented in table 1. However, it should be noted that: firstly, the diagnostic value only concerns the detection of stenoses in the proximal and mid segment of the coronary tree, because the smaller distal segments cannot be adequately visualised; and secondly, only in 70–80 % of these proximal and mid segments is image quality sufficient to allow a semiquantitative assessment. View this table: Table 1 Approximate diagnostic value of non-invasive coronary imaging techniques to detect significant coronary stenosis (> 50 % …

OBJECTIVE--To study the immediate and long term clinical success of percutaneous transluminal coronary balloon angioplasty in patients over 70 years old. DESIGN--Patients undergoing percutaneous transluminal angioplasty were prospectively entered in a specially designed database. The clinical and angiographic data of all patients over 70 were reviewed. Follow up data were collected by interview, during outpatient visits, by questionnaire, or through the referring physician. SETTING--A tertiary referral cardiac centre. PATIENTS--166 patients over 70 (median 73, range 70-84) underwent coronary angioplasty because of unstable angina (81 patients), stable angina (76 patients), or acute myocardial infarction (nine patients). RESULTS--The initial clinical success rate was 86% (142 of 166 patients). A major procedural complication occurred in 10 patients (6%): four patients (2%) died, six patients (4%) underwent emergency bypass surgery, and five patients (3%) sustained an acute myocardial infarction. In 14 patients (8%) coronary angioplasty did not significantly reduce the diameter stenosis but there were no associated complications. A total of 226 lesions were attempted. The initial angiographic success rate was 192 out of 226 lesions (85%). The median follow up was 21 (range 0.5-66) months. Sixteen patients (10%) died during follow up, eight patients (5%) sustained a non-fatal myocardial infarction, 21 patients (13%) underwent a second or third balloon dilatation, and 17 patients (10%) underwent elective bypass surgery. Of the 146 survivors, 99 patients (68%) had sustained clinical improvement. The estimated survival at four years (Kaplan-Meier method) was 89 (SD 4)%. The event free survival at four years for the total study population was 61 (8)%. Multivariate logistic regression analysis showed that the extent of vessel disease was the only independent predictive factor for event free survival: the event free survival rate was 81 (10)% at four years for patients with single vessel disease, compared with 45 (12)% for patients with multivessel disease. CONCLUSIONS--Coronary angioplasty in patients over 70 was a safe and effective treatment for obstructive coronary artery disease. The extent of vessel disease, and not the completeness of revascularisation, was the only independent predictive factor for event free survival.

A 47 year old man with corrected tetralogy of Fallot was admitted with clinical heart failure. After prior left sided Blalock anastomosis at the age of 4 years, complete correction was performed at 9 years of age. Before pulmonary homograft insertion at 40, a fistula between the right coronary artery (RCA) …

We have examined the relation between electrocardiographic ST elevation during treadmill exercise (greater than or equal to 1 mm, using the conventional 12 leads), the severity of coronary artery disease, and left ventricular wall motion abnormalities in 680 patients. They were divided into three groups: (1) 218 patients with clinically significant coronary artery disease, (2) 178 patients with clinically significant coronary artery disease, and (3) 284 patients with clinically significant coronary artery disease and previous myocardial infarction. ST elevation during exercise (predominantly in lead V2) was seen in two patients (1%) in group 1, three patients (2%) in group 2, and 147 patients (52%) in group 3. Coronary artery disease (number of vessels involved and severity of stenoses) was comparable in groups 2 and 3. All the patients in group 1 showed a normal left ventricular contraction pattern; 64% of the patients in group 2 showed wall motion abnormalities (predominantly hypokinesia) and 95% of group 3 (mainly akinesia, dyskinesia, or aneurysm). A strongly positive correlation was seen between the ST elevation and left ventricular dysfunction in patients belonging to group 3. The overall sensitivity and the specificity of the stress test in detecting wall motion abnormalities was 55% and 100% respectively. The sensitivity increased with deterioration in left ventricular function, reaching 81% and 90% in patients with dyskinesia and aneurysm, respectively. Maximal ST elevation (greater than or equal to 3 mm) was confined to the patients with dyskinesia or aneurysm. The incidence of ST elevation during exercise was also related to the location of previous infarction, showing a positive response in 85% of patients with anterior myocardial infarction and in only 33% with inferior myocardial infarction. We conclude that ST segment elevation during exercise in patients with previous myocardial infarction is a sensitive and a specific indicator of advanced left ventricular asynergy. The ST segment response during exercise in patients with previous infarction and with angiographically demonstrated myocardial asynergy appears to be a continuous spectrum. A normal ST segment response or elevation alone usually signifies involvement of only one vessel supplying the infarcted myocardium, ST elevation with concomitant ST depression indicates additional coronary artery disease, and ST depression alone indicates overwhelming myocardial ischaemia resulting from multiple vessel disease. The employment of multiple leads is essential to obtain this information.