Optimal medical therapy with or without percutaneous coronary intervention to reduce ischemic burden: results from the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial nuclear substudy

Coronary revascularisation in chronic kidney disease. Part 1: stable coronary artery disease

Chronic kidney disease (CKD) is associated with a high burden of coronary artery disease, myocardial infarction and cardiovascular death. Detection and treatment of coronary artery disease in CKD patients has been hampered by the limitations of screening tests, the lack of direct evidence for therapeutic interventions in this specific population, and concerns about therapy-related adverse effects. However, these patients potentially have much to gain from conventional strategies used in the general population. This review summarises the current evidence regarding the treatment of coronary artery disease in patients with CKD, with the focus on coronary revascularisation by percutaneous coronary intervention or coronary artery bypass grafting.

Effective radiation dose, time, and contrast medium to measure fractional flow reserve

OBJECTIVES

This study sought to define the additional effective radiation dose, procedural time, and contrast medium needed to obtain fractional flow reserve (FFR) measurements after a diagnostic coronary angiogram.

BACKGROUND

The FFR measurements performed at the end of a diagnostic angiogram allow the obtaining of functional information that complements the anatomic findings.

METHODS

In 200 patients (mean age 66 +/- 10 years) undergoing diagnostic coronary angiography, FFR was measured in at least 1 intermediate coronary artery stenosis. Hyperemia was achieved by intracoronary (n = 180) or intravenous (n = 20) adenosine. The radiation dose (mSv), procedural time (min), and contrast medium (ml) needed for diagnostic angiography and FFR were recorded.

RESULTS

A total of 296 stenoses (1.5 +/- 0.7 stenoses per patient) were assessed. The additional mean radiation dose, procedural time, and contrast medium needed to obtain FFR expressed as a percentage of the entire procedure were 30 +/- 16% (median 4 mSv, range 2.4 to 6.7 mSv), 26 +/- 13% (median 9 min, range 7 to 13 min), and 31 +/- 16% (median 50 ml, range 30 to 90 ml), respectively. The radiation dose and contrast medium during FFR were similar after intravenous and intracoronary adenosine, though the procedural time was slightly longer with intravenous adenosine (median 11 min, range 10 to 17 min, p = 0.04) than with intracoronary adenosine (median 9 min, range 7 to 13 min). When FFR was measured in 3 or more lesions, radiation dose, procedural time, and contrast medium increased.

CONCLUSIONS

The additional radiation dose, procedural time, and contrast medium to obtain FFR measurement are low as compared to other cardiovascular imaging modalities. Therefore, the combination of diagnostic angiography and FFR measurements is warranted to provide simultaneously anatomic and functional information in patients with coronary artery disease.

Economic evaluation of fractional flow reserve-guided percutaneous coronary intervention in patients with multivessel disease

BACKGROUND

The Fractional Flow Reserve Versus Angiography for Multivessel Evaluation (FAME) study demonstrated significantly improved health outcomes at 1 year in patients randomized to multivessel percutaneous coronary intervention guided by fractional flow reserve (FFR) compared with percutaneous coronary intervention guided by angiography alone. The economic impact of routine measurement of FFR in this setting is not known.

METHODS AND RESULTS

In this study, 1005 patients were randomly assigned to FFR-guided or angiography-guided percutaneous coronary intervention and followed up for 1 year. A prospective cost-utility analysis comparing costs and quality-adjusted life-years was performed with a time horizon of 1 year. Quality-adjusted life-years were calculated with the use of utilities determined by the EuroQuol 5 dimension health survey with US weights. Direct medical costs included those of the index procedure and hospitalization and costs for major adverse cardiac events during follow-up. Confidence intervals for both quality-adjusted life-years and costs were estimated by the bootstrap percentile method. Major adverse cardiac events at 1 year occurred in 13.2% of those in the FFR-guided arm and 18.3% of those in the angiography-guided arm (P=0.02). Quality-adjusted life-years were slightly greater in the FFR-guided arm (0.853 versus 0.838; P=0.2). Mean overall costs at 1 year were significantly less in the FFR-guided arm ($14 315 versus $16 700; P<0.001). Bootstrap simulation indicated that the FFR-guided strategy was cost-saving in 90.74% and cost-effective at a threshold of US $50 000 per quality-adjusted life-years in 99.96%. Sensitivity analyses demonstrated robust results.

CONCLUSION

Economic evaluation of the FAME study reveals that FFR-guided percutaneous coronary intervention in patients with multivessel coronary disease is one of those rare situations in which a new technology not only improves outcomes but also saves resources. Clinical Trial Registration- URL: http://ClinicalTrials.gov. Unique identifier: NCT00267774.

Multiple testing, cumulative radiation dose, and clinical indications in patients undergoing myocardial perfusion imaging

CONTEXT

Myocardial perfusion imaging (MPI) is the single medical test with the highest radiation burden to the US population. Although many patients undergoing MPI receive repeat MPI testing, or additional procedures involving ionizing radiation, no data are available characterizing their total longitudinal radiation burden and relating radiation burden with reasons for testing.

OBJECTIVES

To characterize procedure counts, cumulative estimated effective doses of radiation, and clinical indications for patients undergoing MPI.

DESIGN, SETTING, AND PATIENTS

A retrospective cohort study of 1097 consecutive patients undergoing index MPI during the first 100 days of 2006 (January 1-April 10) at Columbia University Medical Center, New York, New York, that evaluated all preceding medical imaging procedures involving ionizing radiation undergone beginning October 1988, and all subsequent procedures through June 2008, at the center.

MAIN OUTCOME MEASURES

Cumulative estimated effective dose of radiation, number of procedures involving radiation, and indications for testing.

RESULTS

Patients underwent a median of 15 (interquartile range [IQR], 6-32; mean, 23.9) procedures involving radiation exposure; of which 4 (IQR, 2-8; mean, 6.5) were high-dose procedures (≥3 mSv; ie, 1 year's background radiation), including 1 (IQR, 1-2; mean, 1.8) MPI study per patient. A total of 344 patients (31.4%) received cumulative estimated effective dose from all medical sources of more than 100 mSv. Multiple MPIs were performed in 424 patients (38.6%), for whom cumulative estimated effective dose was 121 mSv (IQR, 81-189; mean, 149 mSv). Men and white patients had higher cumulative estimated effective doses. More than 80% of initial and 90% of repeat MPI examinations were performed in patients with known cardiac disease or symptoms consistent with it.

CONCLUSION

In this institution, multiple testing with MPI was common and in many patients associated with high cumulative estimated doses of radiation.

Impact of completeness of revascularization on the five-year outcome in percutaneous coronary intervention and coronary artery bypass graft patients (from the ARTS-II study)

The aim of this study was to compare clinical outcome at 5 years in patients with complete and incomplete revascularization treated with coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with drug-eluting stents. Baseline and procedural angiograms and surgical case-record forms were centrally assessed for completeness of revascularization. Patients treated with PCI for incomplete revascularization were stratified according to Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score tertiles. Complete revascularization was achieved in 360 of 588 patients (61.2%) in the PCI with sirolimus-eluting stent group and 477 of 567 patients (84.1%) in the CABG group (p <0.05). There was no significant difference in 5-year survival without major adverse cardiac and cerebrovascular events (MACCEs; death, cerebrovascular accident, myocardial infarction, and any revascularization) between patients with complete and incomplete revascularization treated with PCI or CABG. Survival free from MACCEs in patients with incomplete revascularization treated with PCI was significantly lower than those with complete revascularization treated with CABG (hazard ratio 1.66, 0.96 to 1.80, log-rank p = 0.001). The 5-year MACCE-free survival in patients with incomplete revascularization treated with PCI stratified according to SYNTAX score tertiles showed a significantly lower MACCE survival in the higher SYNTAX tertile compared to the low (hazard ratio 0.56, 0.32 to 0.96, log-rank p = 0.04) and intermediate (hazard ratio 0.50, 0.28 to 0.91, log-rank p = 0.02) tertiles, whereas survival between the low and intermediate SYNTAX tertiles was not significantly different (hazard ratio 1.13, 0.60 to 2.13, log-rank p = 0.71). In conclusion, this study suggests that patients with complex coronary disease, in whom complete revascularization cannot be achieved with PCI, should be offered surgical revascularization. However, in those patients with less complex disease, PCI is a valid alternative even if complete revascularization cannot be achieved.

Myocardial perfusion imaging using a technetium-99m sestamibi in asymptomatic and low risk for coronary artery disease patients with diagnosed systemic lupus erythematosus

INTRODUCTION

The aim of the present study was to evaluate technetium-99m sestamibi single photon emission tomography (SPECT) myocardial perfusion imaging (MPI) and its association with some clinical and laboratory parameters in an asymptomatic systemic lupus erythematosus (SLE) population.

MATERIALS AND METHODS

Twenty-one subjects with SLE and no suspected or documented coronary artery disease (CAD) accomplished myocardial perfusion imaging. Some SLE and CAD parameters were also evaluated in association with myocardial SPECT.

RESULTS

Twenty-one women with a diagnosis of SLE (mean age 36.9 ± 12.8) entered the study. All patients were in the low-risk category for CAD pretest; however, abnormal myocardial perfusion results were found in eight (38%) patients. Amongst the traditional CAD risk factors, there was a significant association between the presence of dyslipidemia and myocardial perfusion abnormalities (P= 0.047). However, we found no significant association between other traditional and SLE-specific risk factors.

CONCLUSION

This study's significant finding was that asymptomatic CAD is common in SLE patients, even in those thought to be low risk for CAD and in the absence of cardiac symptoms.

Off-pump coronary artery bypass vs percutaneous coronary intervention. Therapeutic strategies for 3-vessel coronary artery disease: OPCAB vs PCI(PCI-Side)

Coronary artery bypass graft (CABG) surgery is still the best therapy for patients with multivessel and left main coronary artery disease. Recently, the introduction of percutaneous coronary intervention (PCI) with drug-eluting stents (DES) in these patients has improved the restenosis rate compared with bare metal stents. Furthermore, according to the results of the SYNTAX trial, no differences were found in the frequencies of mortality or myocardial infarction between CABG and PCI patients. PCI with DES is being increasingly performed for the treatment of patients with either left main trunk, diffuse, or multivessel lesions. In Japan, to avoid any side effects from cardiopulmonary bypass, off-pump coronary artery bypass (OPCAB) was performed in 66% of the total isolated CABG procedures in 2009, and is markedly different from the procedures performed in North America and Europe. However, the comparative effectiveness of PCI and OPCAB remains uncertain. In the present study, the current evidence from randomized trials, a meta-analysis and several observation studies are reviewed.

Is angioplasty able to become the gold standard of treatment beyond bypass surgery for patients with multivessel coronary artery disease? Therapeutic strategies for 3-vessel coronary artery disease: OPCAB vs PCI(PCI-Side)

This article reviews the treatment of patients with multivessel coronary artery disease (CAD). Percutaneous coronary intervention (PCI) has been challenging coronary artery bypass grafting (CABG) as the gold standard of care for patients with multivessel disease; however, the application of PCI to these patients has been mainly limited by restenosis. Up to the beginning of the 2000s, many large-scale, randomized trials addressed this issue by comparing CABG to PCI with balloon angioplasty or bare metal stents in not only Western countries but also in Asian countries. These studies demonstrated similar rates of all-cause death and myocardial infarction in both groups, although the need for revascularization remained significantly lower in the CABG group. PCI with drug-eluting stents (DES) is safe and may represent a viable alternative to CABG for selected patients with diabetes and multivessel CAD. Moreover, DES implantation under intravascular ultrasound guidance and with fractional flow reserve might have the potential to influence treatment strategy and reduce both DES thrombosis and repeat revascularization. The evolution of DES and advanced vascular imaging would mean that PCI continues to challenge CABG as treatment of choice for patients who need revascularization for a better prognosis.

Prognostic value of high-dose dobutamine stress magnetic resonance imaging in 1,493 consecutive patients: assessment of myocardial wall motion and perfusion

OBJECTIVES

This study sought to determine the prognostic value of wall motion and perfusion assessment during high-dose dobutamine stress (DS) cardiac magnetic resonance imaging (MRI) in a large patient cohort.

BACKGROUND

DS-MRI offers the possibility to integrate myocardial perfusion and wall motion analysis in a single examination for the detection of coronary artery disease (CAD).

METHODS

A total of 1,493 consecutive patients with suspected or known CAD underwent DS-MRI, using a standard protocol in a 1.5-T magnetic resonance scanner. Wall motion and perfusion were assessed at baseline and during stress, and outcome data including cardiac death, nonfatal myocardial infarction ("hard events"), and "late" revascularization performed >90 days after the MR scans were collected during a 2 ± 1 year follow-up period.

RESULTS

Fifty-three hard events, including 14 cardiac deaths and 39 nonfatal infarctions, occurred during the follow-up period, whereas 85 patients underwent "late" revascularization. Using multivariable regression analysis, an abnormal result for wall motion or perfusion during stress yielded the strongest independent prognostic value for both hard events and late revascularization, clearly surpassing that of clinical and baseline magnetic resonance parameters (for wall motion: adjusted hazard ratio [HR] of 5.9 [95% confidence interval (CI): 2.5 to 13.6] for hard events and of 3.1 [95% CI: 1.7 to 5.6] for late revascularization, and for perfusion: adjusted HR of 5.4 [95% CI: 2.3 to 12.9] for hard events and of 6.2 [95% CI: 3.3 to 11.3] for late revascularization, p < 0.001 for all).

CONCLUSIONS

DS-MRI can accurately identify patients who are at increased risk for cardiac death and myocardial infarction, separating them from those with normal findings, who have very low risk for future cardiac events. (Prognostic Value of High Dose Dobutamine Stress Magnetic Resonance Imaging; NCT00837005).

Quantitative upright-supine high-speed SPECT myocardial perfusion imaging for detection of coronary artery disease: correlation with invasive coronary angiography

A recently developed camera system for high-speed SPECT (HS-SPECT) myocardial perfusion imaging shows excellent correlation with conventional SPECT. Our goal was to test the diagnostic accuracy of an automated quantification of combined upright and supine myocardial SPECT for detection of coronary artery disease (CAD) (≥ 70% luminal diameter stenosis or, in left main coronary artery, ≥ 50% luminal diameter stenosis) in comparison to invasive coronary angiography (ICA).

METHODS

We studied 142 patients undergoing upright and supine HS-SPECT, including 56 consecutive patients (63% men; mean age ± SD, 64 ± 13 y; 45% exercise stress) without known CAD who underwent diagnostic ICA within 6 mo of HS-SPECT and 86 consecutive patients with a low likelihood of CAD. Reference limits for upright and supine HS-SPECT were created from studies of patients with a low likelihood of CAD. Automated software adopted from supine-prone analysis was used to quantify the severity and extent of perfusion abnormality and was expressed as total perfusion deficit (TPD). TPD was obtained for upright (U-TPD), supine (S-TPD), and combined upright-supine acquisitions (C-TPD). Stress U-TPD ≥ 5%, S-TPD ≥ 5%, and C-TPD ≥ 3% myocardium were considered abnormal for per-patient analysis, and U-TPD, S-TPD, and C-TPD ≥ 2% in each coronary artery territory were considered abnormal for per-vessel analysis.

RESULTS

On a per-patient basis, the sensitivity was 91%, 88%, and 94% for U-TPD, S-TPD, and C-TPD, respectively, and specificity was 59%, 73%, and 86% for U-TPD, S-TPD, and C-TPD, respectively. C-TPD had a larger area under the receiver-operating-characteristic curve than U-TPD or S-TPD for identification of stenosis ≥ 70% (0.94 vs. 0.88 and 0.89, P < 0.05 and not significant, respectively). On a per-vessel basis, the sensitivity was 67%, 66%, and 69% for U-TPD, S-TPD, and C-TPD, respectively, and specificity was 91%, 94%, and 97% for U-TPD, S-TPD, and C-TPD, respectively (P = 0.02 for specificity U-TPD vs. C-TPD).

CONCLUSION

In this first comparison of HS-SPECT with ICA, new automated quantification of combined upright and supine HS-SPECT shows high diagnostic accuracy for detecting clinically significant CAD, with findings comparable to those reported using conventional SPECT.

Clinical Role of Hybrid Imaging

Recent technological advances have fueled the growth in hybrid radionuclide and CT imaging of the heart. Noninvasive imaging studies are reliable means to diagnose coronary artery disease (CAD), stratify risk, and guide clinical management. Myocardial perfusion scintigraphy is a robust, widely available noninvasive modality for the evaluation of ischemia from known or suspected CAD. Cardiac CT (coronary artery calcium score and coronary CT angiography) has emerged as a clinically robust noninvasive anatomic imaging test, capable of rapidly diagnosing or excluding obstructive CAD. Both anatomic and functional modalities have strengths and weaknesses, and can complement each other by offering integrated structural and physiologic information. As we discuss below, in selected patients, hybrid imaging may facilitate more accurate diagnosis, risk stratification, and management in a "one-stop shop" setting.

Assessment of the relationship between stenosis severity and distribution of coronary artery stenoses on multislice computed tomographic angiography and myocardial ischemia detected by single photon emission computed tomography

BACKGROUND

The relationship between luminal stenosis measured by coronary CT angiography (CCTA) and severity of stress-induced ischemia seen on single photon emission computed tomographic myocardial perfusion imaging (SPECT-MPI) is not clearly defined. We sought to evaluate the relationship between stenosis severity assessed by CCTA and ischemia on SPECT-MPI.

METHODS AND RESULTS

ECG-gated CCTA (64 slice dual source CT) and SPECT-MPI were performed within 6 months in 292 patients (ages 26-91, 73% male) with no prior history of coronary artery disease. Maximal coronary luminal narrowing, graded as 0, ≥25%, 50%, 70%, or 90% visual diameter reduction, was consensually assessed by two expert readers. Perfusion defect on SPECT-MPI was assessed by computer-assisted visual interpretation by an expert reader using the standard 17 segment, 5 point-scoring model (stress perfusion defect of ≥5% = abnormal). By SPECT-MPI, abnormal perfusion was seen in 46/292 patients. With increasing stenosis severity, positive predictive value (PPV) increased (42%, 51%, and 74%, P = .01) and negative predictive value was relatively unchanged (97%, 95%, and 91%) in detecting perfusion abnormalities on SPECT-MPI. In a receiver operator curve analysis, stenosis of 50% and 70% were equally effective in differentiating between the presence and absence of ischemia. In a multivariate analysis that included stenosis severity, multivessel disease, plaque composition, and presence of serial stenoses in a coronary artery, the strongest predictors of ischemia were stenosis of 50-89%, odds ratio (OR) 7.31, P = .001, stenosis ≥90%, OR 34.05, P = .0001, and serial stenosis ≥50% OR of 3.55, P = .006.

CONCLUSIONS

The PPV of CCTA for ischemia by SPECT-MPI rises as stenosis severity increases. Luminal stenosis ≥90% on CCTA strongly predicts ischemia, while <50% stenosis strongly predicts the absence of ischemia. Serial stenosis of ≥50% in a vessel may offer incremental value in addition to stenosis severity in predicting ischemia.

Cardiac PET imaging for the detection and monitoring of coronary artery disease and microvascular health

Positron emission tomography (PET) myocardial perfusion imaging in concert with tracer-kinetic modeling affords the assessment of regional myocardial blood flow (MBF) of the left ventricle in absolute terms (milliliters per gram per minute). Assessment of MBF both at rest and during various forms of vasomotor stress provides insight into early and subclinical abnormalities in coronary arterial vascular function and/or structure, noninvasively. The noninvasive evaluation and quantification of MBF and myocardial flow reserve (MFR) extend the scope of conventional myocardial perfusion imaging from detection of end-stage, advanced, and flow-limiting, epicardial coronary artery disease (CAD) to early stages of atherosclerosis or microvascular dysfunction. Recent studies have shown that impaired hyperemic MBF or MFR with PET, with or without accompanying CAD, is predictive of increased relative risk of death or progression of heart failure. Quantitative approaches that measure MBF with PET identify multivessel CAD and offer the opportunity to monitor responses to lifestyle and/or risk factor modification and to therapeutic interventions. Whether improvement or normalization of hyperemic MBF and/or the MFR will translate to improvement in long-term cardiovascular outcome remains clinically untested. In the meantime, absolute measures of MBF with PET can be used as a surrogate marker for coronary vascular health, and to monitor therapeutic interventions. Although the assessment of myocardial perfusion with PET has become an indispensable tool in cardiac research, it remains underutilized in clinical practice. Individualized, image-guided cardiovascular therapy may likely change this paradigm in the near future.

Recent advances in the management of chronic stable angina II. Anti-ischemic therapy, options for refractory angina, risk factor reduction, and revascularization

The objectives in treating angina are relief of pain and prevention of disease progression through risk reduction. Mechanisms, indications, clinical forms, doses, and side effects of the traditional antianginal agents - nitrates, β-blockers, and calcium channel blockers - are reviewed. A number of patients have contraindications or remain unrelieved from anginal discomfort with these drugs. Among newer alternatives, ranolazine, recently approved in the United States, indirectly prevents the intracellular calcium overload involved in cardiac ischemia and is a welcome addition to available treatments. None, however, are disease-modifying agents. Two options for refractory angina, enhanced external counterpulsation and spinal cord stimulation (SCS), are presented in detail. They are both well-studied and are effective means of treating at least some patients with this perplexing form of angina. Traditional modifiable risk factors for coronary artery disease (CAD) - smoking, hypertension, dyslipidemia, diabetes, and obesity - account for most of the population-attributable risk. Individual therapy of high-risk patients differs from population-wide efforts to prevent risk factors from appearing or reducing their severity, in order to lower the national burden of disease. Current American College of Cardiology/American Heart Association guidelines to lower risk in patients with chronic angina are reviewed. The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial showed that in patients with stable angina, optimal medical therapy alone and percutaneous coronary intervention (PCI) with medical therapy were equal in preventing myocardial infarction and death. The integration of COURAGE results into current practice is discussed. For patients who are unstable, with very high risk, with left main coronary artery lesions, in whom medical therapy fails, and in those with acute coronary syndromes, PCI is indicated. Asymptomatic patients with CAD and those with stable angina may defer intervention without additional risk to see if they will improve on optimum medical therapy. For many patients, coronary artery bypass surgery offers the best opportunity for relieving angina, reducing the need for additional revascularization procedures and improving survival. Optimal medical therapy, percutaneous coronary intervention, and surgery are not competing therapies, but are complementary and form a continuum, each filling an important evidence-based need in modern comprehensive management.

Cardiac computed tomography and magnetic resonance imaging: the clinical use from a cardiologist's perspective

The introduction and continued evolution of cardiac computed tomography and magnetic resonance imaging have added considerable noninvasive diagnostic insight into a wide range of frequently encountered clinical cardiology scenarios. With an increasing range of imaging modalities, and multiple methods of image acquisition in each, a detailed understanding of the clinical question at hand is often necessary to select the proper study and make optimal use of imaging data. We review common cardiac issues from a clinician's perspective, along with the unique role to be played by computed tomography and magnetic resonance imaging in each condition. This review will hopefully facilitate a strong dialogue between imagers and managing clinicians, creating a shared knowledge of both the capabilities of imaging and the management challenges that treating clinicians face.

Antegrade, retrograde, and combination strategies for chronic total occlusions

Chronic total occlusion (CTO) represents one of the most challenging lesion subsets faced by the interventional cardiologist. CTO is a common problem, being present in more than 30% of patients undergoing coronary angiography. Over the past 10 years, the success rate of recanalization has increased from approximately 50-85%. Developments in guidewire technology, imaging technique, and coronary devices have contributed to the improved prognosis of patients affected by a CTO lesion. Enhancement in antegrade and retrograde techniques of recanalization also result in improved outcomes. Benefits of CTO recanalization may include symptom relief, decreased need for coronary artery bypass graft surgery, improved left ventricular ejection fraction, and in some cases an improved survival.

Angiographic versus functional severity of coronary artery stenoses in the FAME study fractional flow reserve versus angiography in multivessel evaluation

OBJECTIVES

The purpose of this study was to investigate the relationship between angiographic and functional severity of coronary artery stenoses in the FAME (Fractional Flow Reserve Versus Angiography in Multivessel Evaluation) study.

BACKGROUND

It can be difficult to determine on the coronary angiogram which lesions cause ischemia. Revascularization of coronary stenoses that induce ischemia improves a patient's functional status and outcome. For stenoses that do not induce ischemia, however, the benefit of revascularization is less clear.

METHODS

In the FAME study, routine measurement of the fractional flow reserve (FFR) was compared with angiography for guiding percutaneous coronary intervention in patients with multivessel coronary artery disease. The use of the FFR in addition to angiography significantly reduced the rate of all major adverse cardiac events at 1 year. Of the 1,414 lesions (509 patients) in the FFR-guided arm of the FAME study, 1,329 were successfully assessed by the FFR and are included in this analysis.

RESULTS

Before FFR measurement, these lesions were categorized into 50% to 70% (47% of all lesions), 71% to 90% (39% of all lesions), and 91% to 99% (15% of all lesions) diameter stenosis by visual assessment. In the category 50% to 70% stenosis, 35% were functionally significant (FFR <or=0.80) and 65% were not (FFR >0.80). In the category 71% to 90% stenosis, 80% were functionally significant and 20% were not. In the category of subtotal stenoses, 96% were functionally significant. Of all 509 patients with angiographically defined multivessel disease, only 235 (46%) had functional multivessel disease (>or=2 coronary arteries with an FFR <or=0.80).

CONCLUSIONS

Angiography is inaccurate in assessing the functional significance of a coronary stenosis when compared with the FFR, not only in the 50% to 70% category but also in the 70% to 90% angiographic severity category.

The clinical impact of routine angiographic follow-up in randomized trials of drug-eluting stents: a critical assessment of "oculostenotic" reintervention in patients with intermediate lesions

OBJECTIVES

The aim of this study was to study the long-term clinical effects of routine angiographic follow-up and related reintervention after drug-eluting stenting.

BACKGROUND

Prior stent trials have shown that protocol-mandated angiographic follow-up increases repeat interventions compared with clinical follow-up alone. The long-term clinical impact of this practice is unknown.

METHODS

Long-term outcomes of patients assigned to routine angiographic follow-up in 3 large-scale TAXUS (Boston Scientific, Natick, Massachusetts) trials were compared with patients assigned to clinical follow-up alone, in a propensity score-adjusted patient-level meta-analysis. Outcomes were also compared in patients with treated versus untreated nonischemic intermediate lesions (quantitative angiographic stenosis between >or=40% and <70%) detected at angiographic follow-up.

RESULTS

Target lesion revascularization (TLR) rates at 5 years were significantly higher in the angiographic compared with clinical follow-up cohort (18.3% vs. 11.1%, p < 0.001). This was due to more frequent treatment of intermediate lesions, but there was no associated reduction in rates of cardiac death or myocardial infarction (8.9% vs. 8.8%, p = 0.93). Of patients with nonischemic intermediate lesions, 17% who were not revascularized at the time of angiographic follow-up had a subsequent TLR, whereas 7% of patients who had TLR at this follow-up angiogram required additional revascularization during long-term follow-up.

CONCLUSIONS

A strategy of routine angiographic follow-up increases oculostenotic revascularization of nonischemic intermediate lesions without affecting subsequent rates of cardiac death or myocardial infarction, and TLR was not required in 83% of those lesions. A conservative approach, in which repeat angiography is limited to patients with recurrent ischemia or progressive symptoms, minimizes repeat revascularization of nonischemic intermediate lesions and optimizes long-term event-free survival after drug-eluting stent implantation.

Effectiveness of recanalization of chronic total occlusions: a systematic review and meta-analysis

BACKGROUND

Chronic total occlusion (CTO) recanalizations remain extremely challenging procedures. With improvements in technology and techniques, success rates for recanalization of CTO continue to improve. However, the clinical benefits of this practice remain unclear. The aim of the study was to determine the effectiveness of CTO recanalization on clinical outcomes.

METHODS

We performed a systematic review and meta-analysis of published studies comparing CTO recanalization to medical management. Data were extracted in duplicate and analyzed by a random effects model.

RESULTS

We did not identify any randomized controlled trials or observational studies comparing CTO recanalization to a planned medical management. We did identify 13 observational studies comparing outcomes after successful vs failed CTO recanalization attempt. These studies encompassed 7,288 patients observed over a weighted average follow-up of 6 years. There were 721 (14.3%) deaths of 5,056 patients after successful CTO recanalization compared to 390 deaths (17.5%) of 2,232 patients after failed CTO recanalization (odds ratio [OR] 0.56, 95% CI 0.43-0.72). Successful recanalization was associated with a significant reduction in subsequent coronary artery bypass graft surgery (CABG) (OR 0.22, 95% CI 0.17-0.27) but not in myocardial infarction (OR 0.74, 95% CI 0.44-1.25) or major adverse cardiac events (OR 0.81, 95% CI 0.55-1.21). In the 6 studies that reported angina status, successful recanalization was associated with a significant reduction in residual/recurrent angina (OR 0.45, 95% CI 0.30-0.67).

CONCLUSIONS

In highly selected patients considered for CTO recanalization, successful attempts appear to be associated with an improvement in mortality and with a reduction for the need for CABG as compared to failed recanalization. However, given the observational nature of the reviewed evidence, randomized clinical trials are needed to confirm these findings.

Percutaneous coronary intervention in chronic stable angina

Although the therapeutic advantage of percutaneous coronary intervention in acute coronary syndromes have been proved in numerous studies, its position in the treatment of stable angina remains a controversial issue. The results of the recent studies did not lead into definite answers for the proper treatment of chronic coronary artery disease. The identification of the patients that will benefit from the interventional approach is necessary and is probably based on the proper screening for myocardial ischemia with noninvasive diagnostic techniques. In this review article, we mention the most recent studies for the treatment of chronic stable angina with respect to clinical outcome and economical consequences.

Cost-effectiveness of percutaneous coronary intervention in optimally treated stable coronary patients

BACKGROUND

The COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive druG Evaluations) trial compared the effect of percutaneous coronary intervention (PCI) plus optimal medical therapy with optimal medical therapy alone on cardiovascular events in 2287 patients with stable coronary disease. After 4.6 years, there was no difference in the primary end point of death or myocardial infarction, although PCI improved quality of life. The present study evaluated the relative cost and cost-effectiveness of PCI in the COURAGE trial.

METHODS AND RESULTS

Resource use was assessed by diagnosis-related group for hospitalizations and by current procedural terminology code for outpatient visits and tests and then converted to costs by use of 2004 Medicare payments. Medication costs were assessed with the Red Book average wholesale price. Life expectancy beyond the trial was estimated from Framingham survival data. Utilities were assessed by the standard gamble method. The incremental cost-effectiveness ratio was expressed as cost per life-year and cost per quality-adjusted life-year gained. The added cost of PCI was approximately $10,000, without significant gain in life-years or quality-adjusted life-years. The incremental cost-effectiveness ratio varied from just over $168,000 to just under $300,000 per life-year or quality-adjusted life-year gained with PCI. A large minority of the distributions found that medical therapy alone offered better outcome at lower cost. The costs per patient for a significant improvement in angina frequency, physical limitation, and quality of life were $154,580, $112,876, and $124,233, respectively.

CONCLUSIONS

The COURAGE trial did not find the addition of PCI to optimal medical therapy to be a cost-effective initial management strategy for symptomatic, chronic coronary artery disease.

Biomarkers of vulnerable plaque: the missing link with ischemia

The initial evaluation of chest pain in the emergency department is based on the patient’s clinical history, changes in the ECG and necrosis biomarkers. Although management of patients with ST-elevation myocardial infarction or non-ST-elevation myocardial infarction with positive markers of myocardial damage is well defined, exclusion of coronary artery disease or myocardial ischemia in the remaining patients is more challenging. This group represents the majority of patients admitted for chest pain syndromes and that have a substantial risk of an adverse outcome. Given that troponin, as a marker of myocardial damage, detects terminal events in the cascade of acute coronary syndrome, there is a need to search for biomarkers that are able to identify patients at high risk, allowing rapid, bedside stratification. Data suggest that clinical events are prone to occur more frequently in patients with coronary artery stenosis associated with myocardial ischemia. Accordingly, identification of systemic biomarkers of ischemia could facilitate identification of high-risk patients with a high burden of coronary atherosclerosis and plaque rupture. We describe six biomarkers that have been linked to myocardial ischemia. Until now, these biomarkers of ischemia are relevant in order to exclude ischemic heart disease (high negative predictive value) but still lack specificity. Future prospective studies should be performed in larger and more diverse sets of patients presenting with ischemia, and in a complementary fashion in order to provide valuable tools for clinical decision making.

Fractional flow reserve versus angiography for guiding percutaneous coronary intervention in patients with multivessel coronary artery disease: 2-year follow-up of the FAME (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation) study

OBJECTIVES

The purpose of this study was to investigate the 2-year outcome of percutaneous coronary intervention (PCI) guided by fractional flow reserve (FFR) in patients with multivessel coronary artery disease (CAD).

BACKGROUND

In patients with multivessel CAD undergoing PCI, coronary angiography is the standard method for guiding stent placement. The FAME (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation) study showed that routine FFR in addition to angiography improves outcomes of PCI at 1 year. It is unknown if these favorable results are maintained at 2 years of follow-up.

METHODS

At 20 U.S. and European medical centers, 1,005 patients with multivessel CAD were randomly assigned to PCI with drug-eluting stents guided by angiography alone or guided by FFR measurements. Before randomization, lesions requiring PCI were identified based on their angiographic appearance. Patients randomized to angiography-guided PCI underwent stenting of all indicated lesions, whereas those randomized to FFR-guided PCI underwent stenting of indicated lesions only if the FFR was <or=0.80.

RESULTS

The number of indicated lesions was 2.7+/-0.9 in the angiography-guided group and 2.8+/-1.0 in the FFR-guided group (p=0.34). The number of stents used was 2.7+/-1.2 and 1.9+/-1.3, respectively (p<0.001). The 2-year rates of mortality or myocardial infarction were 12.9% in the angiography-guided group and 8.4% in the FFR-guided group (p=0.02). Rates of PCI or coronary artery bypass surgery were 12.7% and 10.6%, respectively (p=0.30). Combined rates of death, nonfatal myocardial infarction, and revascularization were 22.4% and 17.9%, respectively (p=0.08). For lesions deferred on the basis of FFR>0.80, the rate of myocardial infarction was 0.2% and the rate of revascularization was 3.2 % after 2 years.

CONCLUSIONS

Routine measurement of FFR in patients with multivessel CAD undergoing PCI with drug-eluting stents significantly reduces mortality and myocardial infarction at 2 years when compared with standard angiography-guided PCI. (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation [FAME]; NCT00267774).

Current status of cardiovascular magnetic resonance imaging in the assessment of coronary vasculature

The present review describes the contributions of cardiovascular magnetic resonance (CMR) imaging to the assessment of coronary vasculature. It briefly describes various approaches and highlights the value of comprehensive CMR protocols. The limitations of coronary angiography for clinical decision-making and the additional value of plaque imaging and tissues characterization, as well as future directions of CMR and hybrid techniques for assessing microvascular function and myocardial oxygenation, are discussed.

Potent anti-ischaemic effects of statins in chronic stable angina: incremental benefit beyond lipid lowering?

Aims

The DoUble-blind Atorvastatin AmLodipine (DUAAL) trial investigated whether atorvastatin decreases ischaemia by a vascular benefit, independent of low-density lipoprotein cholesterol lowering, in patients with coronary artery disease (CAD), both alone and in combination with the traditional anti-anginal therapy, amlodipine.

Methods and results

Randomized, double-blind, parallel-group, multicountry trial (2 weeks run-in and 24 weeks active therapy) comparing three treatments: amlodipine, atorvastatin, and amlodipine + atorvastatin; in 311 patients (78% male; mean age 62 years) with stable angina (≥2 attacks/week), CAD history, ≥3 transient myocardial ischaemia (TMI) episodes, and/or ≥15 min ischaemia on 48 h ambulatory electrocardiographic (AECG) monitoring. Efficacy variables were change in TMI by AECG, exercise ischaemia, angina diary data, and inflammatory biomarkers at Week 26. There was a comparable, highly significant decrease in TMI with amlodipine and atorvastatin, but no additional benefit for the combination. More than 50% of patients became TMI-free in all three groups and this was accompanied by a comparable, marked reduction in angina and nitroglycerin consumption. High-sensitivity C-reactive protein fell by 40% in patients receiving atorvastatin but there was no change with amlodipine. Adverse events were comparable among groups.

Conclusion

Atorvastatin was as potent an anti-ischaemic agent as amlodipine. Future studies of combination therapies will be instructive.

Clinical trial registration information: National clinical trial number: NCT00159718, protocol number A0531031 listed on http://clinicaltrials.gov/.

Multicenter trial of high-speed versus conventional single-photon emission computed tomography imaging: quantitative results of myocardial perfusion and left ventricular function

OBJECTIVES

This prospective, multicenter trial compared quantitative results of myocardial perfusion imaging and function using a high-speed single-photon emission computed tomography (SPECT) system with those obtained with conventional SPECT.

BACKGROUND

A novel SPECT camera was shown in a pilot study to detect a similar amount of myocardial perfusion abnormality compared with conventional SPECT in one-seventh of the acquisition time.

METHODS

A total of 238 patients underwent myocardial perfusion imaging with conventional and high-speed SPECT at 4 U.S. centers. An additional 63 patients with a low pre-test likelihood of coronary artery disease underwent myocardial perfusion imaging with both technologies to develop method- and sex-specific normal limits. Rest/stress acquisition times were, respectively, 20/15 min and 4/2 min for conventional and high-speed SPECT. Stress and rest quantitative total perfusion deficit, post-stress left ventricular end-diastolic volume, and ejection fraction were derived for the 238 patients by the 2 methods.

RESULTS

High-speed stress and rest total perfusion deficit correlated linearly with conventional SPECT total perfusion deficit (r = 0.95 and 0.97, respectively, p < 0.0001), with good concordance in the 3 vascular territories (kappa statistics for the left anterior descending coronary artery, left circumflex coronary artery, and right coronary artery were 0.73, 0.73, and 0.70, respectively; >90% agreement). The percentage of ischemic myocardium by both imaging modalities was significantly larger in patients with a high coronary artery disease likelihood than in those with a low and intermediate likelihood (p < 0.001). The average amount of ischemia was slightly but significantly larger by high-speed SPECT compared with conventional SPECT in high-likelihood patients (4.6 +/- 4.6% vs. 3.9 +/- 4.0%, respectively; p < 0.05). Post-stress ejection fraction and end-diastolic volume by the 2 methods were linearly correlated (r = 0.89 and 0.97, respectively).

CONCLUSIONS

The high-speed SPECT technology provides quantitative measures of myocardial perfusion and function comparable to those with conventional SPECT in one-seventh of the acquisition time.