American College of Cardiology/Society for Cardiac Angiography and Interventions Clinical Expert Consensus Document on cardiac catheterization laboratory standards. A report of the American College of Cardiology Task Force on Clinical Expert Consensus Documents

In-vivo accuracy of geometrically correct three-dimensional reconstruction of human coronary arteries: is it influenced by certain parameters?

OBJECTIVE

The geometrically correct three-dimensional reconstruction of human coronary arteries by integrating intravascular ultrasound (IVUS) and biplane angiography constitutes a promising imaging method for coronaries with broad clinical potential. The determinants of the accuracy of the method, however, have not been investigated before.

METHODS

In total, 17 arterial segments (right coronary artery, n=7; left anterior descending, n=4; left circumflex, n=6) derived from nine patients were three-dimensionally reconstructed by applying three-dimensional intravascular ultrasound. The degree of matching between the reconstructed lumen back-projected onto each angiographic plane and the actual lumen in each plane was used as a measure of method's accuracy. The investigated factors that could potentially affect the reliability of the method included the type of the artery (left anterior descending, left circumflex, right coronary artery) and several geometrical and morphological characteristics of the reconstructed arteries.

RESULTS

The correlation between the back-projected reconstructed lumens and the actual angiographic ones was found to be high (r=0.78, P<0.001). Neither the category of the reconstructed arteries nor their particular geometrical and morphological characteristics influenced the accuracy of the reconstruction method significantly. Nonetheless, the method exhibited slightly less accuracy in the reconstruction of right coronary arteries, an observation that could be attributed to the more intense pulsatile motion that this artery experiences during the cardiac cycle compared to the left anterior descending and left circumflex artery.

CONCLUSIONS

The in-vivo accuracy of three-dimensional intravascular ultrasound (3D IVUS) is significantly high regardless of the type of the coronary arteries or their particular geometrical and morphological characteristics. This finding further supports the applicability of the method for either diagnostic or investigational purposes.

Detection of transplant coronary artery disease using multidetector computed tomography with adaptative multisegment reconstruction

OBJECTIVES

This study sought to determine whether multidetector computed tomography (MDCT) may be able to detect occlusive coronary disease in transplanted hearts.

BACKGROUND

In heart transplant recipients, asymptomatic coronary disease requiring frequent surveillance commonly develops. Recent advancements in MDCT allow for noninvasive assessment of the coronary vessels.

METHODS

Electrocardiogram-gated contrast-enhanced MDCT scans (16 x 0.75-mm detectors, 420 ms rotation, 100 ml contrast) with multisegment reconstruction were performed on 54 transplant recipients within 6 +/- 11 days of quantitative coronary angiography (QCA). Heart rate at the time of the scan was 90 +/- 11 beats/min. Coronary arterial segments >1.5 mm in diameter were analyzed by independent investigators.

RESULTS

There was a good correlation between MDCT and QCA percent stenosis (r = 0.75, p < 0.01, SEE = 15%). Of the 791 segments identified by QCA, 754 (95%) were analyzable by MDCT. The sensitivity, specificity, and positive and negative predictive values of MDCT compared with QCA for the detection of segments with significant (>50%) stenosis were 86%, 99%, 81%, and 99%, respectively. The MDCT correctly identified 15 of the 16 (94%) transplant patients classified by QCA as having occlusive coronary artery disease and 29 of the 37 patients without significant stenosis (78%). In 1 patient who received intravenous beta-blockers, transient bradycardia requiring temporary pacing developed, but there were no other complications.

CONCLUSIONS

Detection of occlusive coronary disease in heart transplant recipients with elevated resting heart rate by MDCT is feasible using multicycle reconstruction. The need for surveillance invasive coronary angiography in transplant recipients might be mitigated by use of MDCT.

Quality Management and Volume-Related Outcomes in the Cardiac Catheterization Laboratory

The assessment of quality in the cardiac catheterization laboratory is a complex, ongoing process that requires a comprehensive analysis of the multiple elements of quality. Although clinical outcomes are a reflection of the quality process, they derive from a complex interaction of clinical, technical, and process-of-care components. Procedural volume is associated but not equated with clinical outcomes, although the magnitude of this association depends on numerous covariates, most notably the diminishing rate of adverse outcomes over time.

Predictors of Vascular Complications Post Diagnostic Cardiac Catheterization and Percutaneous Coronary Interventions

Care of patients after cardiac catheterization and/or percutaneous coronary intervention is largely the responsibility of nurses. The identification of risk factors for vascular complications from these procedures is important for the development of protocols to prevent complications. This article describes a retrospective, descriptive, and correlational study of 11,119 patients who underwent cardiac catheterization and/or percutaneous intervention, with femoral artery access, in the years 2001 to 2003. Increased risk for vascular complications was found in patients who were older than 70 years, were female, had renal failure, underwent percutaneous intervention, and had a venous sheath.

Coronary artery imaging with multidetector computed tomography: a call for an evidence-based, multidisciplinary approach

Modern multidetector computed tomography systems are capable of a comprehensive assessment of the cardiovascular system, including noninvasive assessment of coronary anatomy. Multidetector computed tomography is expected to advance the role of noninvasive imaging for coronary artery disease, but clinical experience is still limited. Clinical guidelines are necessary to standardize scanner technology and appropriate clinical applications for coronary computed tomographic angiography. Further evaluation of this evolving technology will benefit from cooperation between different medical specialties, imaging scientists, and manufacturers of multidetector computed tomography systems, supporting multidisciplinary teams focused on the diagnosis and treatment of early and advanced stages of coronary artery disease. This cooperation will provide the necessary education, training, and guidelines for physicians and technologists assuring standard of care for their patients.

CT angiography in highly calcified arteries: 2D manual vs. modified automated 3D approach to identify coronary stenoses

BACKGROUND

Two-dimensional axial and manually-oriented reformatted images are traditionally used to analyze coronary data provided by multidetector-row computed tomography angiography (MDCTA). While apparently more accurate in evaluating calcified vessels, 2D methods are time-consuming compared with automated 3D approaches. The purpose of this study was to evaluate the performance of a modified automated 3D approach (using manual vessel isolation and different window and level settings) in a population with high calcium scores who underwent coronary half-millimeter 16-detector-row CT angiography (16 x 0.5-MDCTA).

METHODS

ECG-gated 16 x 0.5-MDCTA (16 x 0.5 mm cross-sections, 0.35 x 0.35 x 0.35 mm3 isotropic voxels, 400 ms rotation) was performed after injection of iopamidol (120-ml, 300 mg/ml) in 19 consecutive patients (11 male, 62+/-10 years-old). Native arteries were independently evaluated for >or=50%-stenoses using both manual 2D and modified automated 3D approaches. Stents and bypass grafts were excluded. Conventional coronary angiography was visually analyzed by 2 observers.

RESULTS

Median Agatston calcium score was 434. Sensitivities, specificities, positive and negative predictive values for detection of >or=50% coronary stenoses using the 2D and modified 3D approaches were, respectively: 74%/63%, 76%/80%, 45%/34%, and 91%/93% (p=NS for all comparisons). Overall diagnostic accuracies were 75 and 78%, respectively (p=NS). Uninterpretable vessels were, respectively: 37% (77/209) and 35% (73/209) - p=NS. Time to analyze a single study was 160+/-23 and 53+/-11 min, respectively (p<0.01).

CONCLUSIONS

This modified automated 3D approach is equivalent to and significantly less time consuming than the traditional manual 2D method for evaluation of >or=50%-stenoses by 16 x 0.5-MDCTA in native coronary arteries of patients with high calcium scores.

Randomized study of the safety and clinical utility of rotational vs. standard coronary angiography using a flat-panel detector

The purpose of this study was to test the hypothesis that rotational angiography improves patient safety while maintaining diagnostic accuracy for patients undergoing coronary angiography. Despite advances in angiographic technique, patients remain at risk for complications of coronary angiography, including contrast-induced nephropathy and radiation exposure. Technology has been developed to perform coronary angiography with active rotation of the imaging system that may reduce the quantity of contrast and radiation to which the patient is exposed. Fifty patients undergoing diagnostic cardiac catheterization were randomized to either standard vs. rotational angiography of the coronary arteries using a prespecified protocol with a flat-panel single-plane imaging system. We measured the quantity of radiographic contrast utilized and radiation exposure. Using an intention-to-treat analysis, there was a 40% reduction (24 +/- 5 vs. 40 +/- 10 ml; P < 0.0001) in contrast utilization in the rotational group compared to the standard group. Neither radiation exposure (35 +/- 14 vs. 30 +/- 20 Gycm(2); P = 0.35), fluoroscopic time (44 +/- 33 vs. 44 +/- 40 sec; P = 0.99), nor procedure time (249 +/- 137 vs. 214 +/- 79 sec; P = 0.26) differed, although significant intraoperator variability was noted for both standard and rotational angiography. The radiation exposure using this flat-panel system is significantly lower than prior reports that used an image intensifier system. Rotational coronary angiography has the potential to improve patient safety by markedly reducing radiographic contrast exposure while maintaining comparable diagnostic accuracy, radiation exposure, and procedure time compared to standard coronary angiography.

Non-invasive coronary angiography with 16-slice spiral computed tomography: image quality in patients with high heart rates

The purpose of this study was to assess segment image quality at high heart rates using 16-slice computed tomography and differential reconstruction for major coronary vessels. According to the following protocol, 16-slice CT coronary angiography in 46 patients with a mean heart rate of 86.3+/-11.8 was reconstructed. At three transverse planes, preview series were obtained and motion artifacts evaluated in 5% increments from 0-95% within the cardiac cycle. Relying on image quality in the previews, reconstructions were performed at three z-positions for each patient. Segment image quality was assessed in terms of artifacts and visibility. The effects of heart rate and trigger delay on image quality were analyzed. Optimal image quality was achieved at 25 to 35% of the cardiac cycle for the left circumflex (CX) and right coronary artery (RCA) or 30 to 40% for the left main (LM) and left anterior descending artery (LAD). Sixteen-slice CT and differential reconstruction produced good image quality with a low percentage of motion-degraded proximal and middle segments (8.8%). Grades were 1.5 for the LM, 1.9 for the LAD, 2.0 for the CX and 2.3 for the RCA. At high heart rates, good image quality of the coronary arteries is achieved by 16-slice CT and a sophisticated reconstruction strategy at peak to late systole.

Non-invasive multislice computed tomography coronary angiography for imaging coronary arteries, stents and bypass grafts

Abstract Multislice computed tomography (MSCT) is evolving rapidly and available data suggest that MSCT coronary angiography may be a reliable and accurate non-invasive imaging modality of coronary arteries. Current generations of MSCT scanners have high sensitivity and specificity for diagnosing native coronary artery disease and coronary bypass graft occlusion. The performance of MSCT in the evaluation of stent patency is still being assessed. In comparison with conventional selective coronary angiography (SCA), MSCT is non-invasive, cheaper and it has the advantages of imaging plaque compositions as well as assessment of luminal patency. Nevertheless, the role of MSCT in the management of coronary artery disease is yet to be fully defined.

Cardiac imaging techniques in systemic autoimmune diseases

Systemic autoimmune disorders are frequently associated to cardiac involvement and to a high prevalence of ischemic coronary events, often occurring at a younger age than in the normal population. Large increase in mortality is related to premature atherosclerosis with coronary artery disease and stroke in patients with connective tissue diseases. Coronary heart disease is responsible for 40-50% of the deaths of patients with rheumatoid arthritis. Transesophageal or transthoracic echocardiography are the most useful and noninvasive techniques able to detect not only valvular abnormalities, embolic sources or pulmonary hypertension, but also left ventricular systolic or diastolic dysfunction. Furthermore, the introduction of new indexes, contrast agents and software increased the accuracy of this technique. It is possible now to evaluate coronary flow reserve by transthoracic echocardiography in patients with systemic autoimmune disease in order to detect microvasculature disorder. However, an ischemic response in a symptomatic patient requires, in most cases, further evaluation with cardiac catheterization. Coronary artery imaging allows confirmation of the presence, extent and position of atheromatous lesions. More recently, other imaging modalities including magnetic resonance and computerized tomography angiography have been developed to allow imaging of the coronary arteries.

Complications of diagnostic cardiac catheterisation: results from a confidential inquiry into cardiac catheter complications

OBJECTIVES

To estimate the frequency and nature of complications in patients undergoing diagnostic cardiac catheterisation and to assess time trends in complications since the introduction of a voluntary cooperative audit.

METHODS

Cardiac centres undertaking diagnostic cardiac catheterisation in England and Wales during the 10 years 1990-9 were invited to join the study. Each participating centre reported numbers of patients catheterised each month and details of complications and deaths as they occurred. Complication rates were calculated for the main diagnostic procedures and for each participating hospital and time trends in complications were examined.

RESULTS

41 cardiac centres contributed. 211 645 diagnostic procedures in adults and 7582 paediatric procedures were registered. The majority (87%) of diagnostic catheter studies in adults were left heart studies with coronary arteriography. The overall complication rate for adult procedures was 7.4/1000, with mortality at 0.7/1000; for paediatric procedures the complication rate was similar but mortality rather higher. Complication rates varied between centres but there was little association with caseload. Time trends across the decade showed both complication and mortality decreasing; from 9.5 to 5.8/1000 and from 1.4 to 0.4/1000, respectively.

CONCLUSION

Complication rates of diagnostic catheterisation are low but neither negligible nor irreducible. While voluntary audit of cardiac catheter complications is useful and inexpensive, there is a clear need to establish a formal reporting system in all cardiac catheter laboratories, with clear definitions of reportable complications.

Computed tomographic coronary angiography: experience at Baylor University Medical Center/Baylor Jack and Jane Hamilton Heart and Vascular Hospital

Noninvasive cardiac computed tomographic imaging using multislice or electron beam technology has been shown to be highly specific and sensitive in diagnosing coronary heart disease. It is about a fifth of the cost of coronary angiography and is particularly well suited for evaluating patients with a low or low to moderate probability of having obstructive coronary atherosclerosis. In addition, it offers more information than calcium scoring: because of the intravenous contrast used, it temporarily increases the density of the lumen and allows differentiation of soft plaque from calcified plaque. The Baylor Hamilton Heart and Vascular Hospital now uses this modality to define coronary atherosclerosis in patients who would otherwise have needed invasive coronary angiography; several research protocols with the technique are also under way. Baylor has recently upgraded to the 64-slice scanner. It is expected that computed tomographic coronary angiography will replace a significant percentage of invasive cardiac catheterizations.

The response to inhaled nitric oxide in patients with pulmonary artery hypertension is not masked by baseline vasodilator use

BACKGROUND

Assessment of pulmonary vasodilator responsiveness is important in determining the prognosis and management of patients with pulmonary hypertension. Many patients, however, are already on vasodilators at the time of testing. It is unclear if these agents should be temporarily discontinued to improve the sensitivity of testing.

METHODS

We examined the hemodynamic effects of nitric oxide (NO) inhalation in 60 patients with pulmonary arterial hypertension. Thirty-one of these patients were receiving medications with vasodilating properties. Vasodilator testing was performed with invasive measurement of pressure of the right side of the heart at baseline and during inhalation of 40 ppm NO.

RESULTS

No significant demographic differences were seen between patients receiving and not receiving vasodilators. Similar reductions in mean pulmonary artery pressure (19 +/- 12% vs 20 +/- 12%, P = .734) and pulmonary vascular resistance (31 +/- 18 vs 32 +/- 16, P = .967) were seen in patients receiving and not receiving vasodilators. Using the definition of positive vasodilator response (> or = 20% drop in mean pulmonary artery pressure), 55% (17/31) of patients in the baseline vasodilator group had a positive response compared with 62% (18/29) of the patients not on vasodilators (P = .570).

CONCLUSIONS

Concurrent use of oral vasodilators does not appear to mask a significant response to inhaled NO on the pulmonary vasculature. Therefore, routine discontinuation of pulmonary vasodilators is likely unnecessary before vasodilator testing in patients with pulmonary arterial hypertension.

Incidence and predictors of target vessel revascularization and clinical event rates of the sirolimus-eluting coronary stent (results from the prospective multicenter German Cypher Stent Registry)

Randomized trials have demonstrated the ability of drug-eluting stents to decrease the risk of restenosis after coronary stent implantation. However, the incidences of major cardiovascular/cerebral adverse events (MACCEs) and target vessel revascularization (TVR) during follow-up in a routine clinical setting remain to be determined. We analyzed data of the multicenter German Cypher Stent Registry. From April 2002 to March 2003, 1,726 patients at 93 hospitals who received >/=1 sirolimus-eluting coronary stent were included. Median follow-up was 6.7 months. During follow-up, death occurred in 1.2% of patients (20 of 1,726), nonfatal myocardial infarction in 2.5% (43 of 1,706), and nonfatal stroke in 0.5% (7 of 1,469). TVR was performed in 8.6% of patients, with percutaneous coronary intervention in 7.3% and coronary artery bypass grafting in 1.5%. The overall rate of MACCEs or TVR was 10.8% (186 of 1,726). Independent predictors of TVR were the target vessel being a bypass graft (odds ratio [OR] 2.43, 95% confidence interval [CI] 1.41 to 4.18, p = 0.001), management of >1 lesion during the same intervention (OR 1.75, 95% CI 1.04 to 2.96, p = 0.035), 2- or 3-vessel disease (OR 1.69, 95% CI 1.05 to 2.72, p = 0.030), and age (per decade; OR 0.82, 95% CI 0.69 to 0.98, p = 0.025). These data confirm the safety and effectiveness of using the sirolimus-eluting stent in daily clinical practice. The management of bypass grafts and multiple lesions in 1 session and the presence of multivessel disease were predictors of MACCEs or TVR.

Catheter interventions for congenital heart disease in third world countries

The term "Third World" loosely encompasses a group of middle- and low-income countries. Considerable differences exist in health care delivery and health indices among these countries. The vast majority of children in the Third World do not have health insurance for congential heart disease (CHD). Catheter interventions for CHD are expensive because of installation costs of expensive biplane equipment, the requirement of dedicated personnel, and the need to stock a large inventory of expensive hardware. As a result, many catheter intervention procedures are beyond the reach of the average patient in the developing world. The following cost-effective strategies have evolved in selected institutions that have attempted to perform catheter interventions for CHD at an affordable cost: sharing of space, equipment, and support personnel with a busy adult cardiology program; use of single plane equipment; the development of sedation protocols to reduce the need for anesthesiologists; strategies to reduce procedure time; reuse of hardware through ethylene oxide sterilization; improvisations to use adult hardware items for CHD interventions; judicious case selection; and improvised alternatives to occlusive devices. These strategies may help reduce costs and allow a larger proportion of patients in developing countries with CHD to undergo interventions. However, the safety of these strategies and the cost savings need to be carefully evaluated prospectively.

Review of Subacute Stent Thrombosis Following Percutaneous Coronary Intervention at a Low‐Volume Catheterization Laboratory

BACKGROUND

The frequency of coronary stent subacute thrombosis (SAT) following percutaneous coronary intervention (PCI) with uncoated stents in recent studies is 0.5%-0.9%. Prior studies have indicated that complication rates are significantly higher when performed in low-volume centers. We sought to determine the incidence and outcomes of SAT following PCI with stent placement at a low-volume catheterization laboratory.

METHODS

We reviewed the Brooke Army Medical Center Interventional Database for all consecutive PCIs with stent implantation performed from January 1998 to December 2002. Clinical outcomes were obtained primarily through hospitalization records and clinic follow-up visits.

RESULTS

There were 789 interventions with stenting on 750 patients over the specified time period, for an average of 158 procedures on 150 patients per year. There were seven cases of SAT, representing a rate of 0.89%. There was no difference in the clinical characteristics, procedural technique, or postprocedural antithrombotic therapy of the subjects with and without SAT. Of those with SAT, there were no subjects requiring surgical revascularization during index hospitalization, and all survived to index hospital discharge. Six of these seven subjects with SAT (85.7%) were alive at one year, with the single death noncardiovascular related.

CONCLUSIONS

The incidence of thrombosis occurring within 30 days of intracoronary stent implantation is similar in low- and high-volume catheterization laboratories. In our low-volume laboratory experience, these events were not associated with significantly increased adverse outcomes.

Noninvasive coronary angiography with 16-detector row CT: effect of heart rate

PURPOSE

To evaluate the effect of heart rate on the quality of coronary angiograms obtained with 16-detector row computed tomography (CT) by using temporally enhanced three-dimensional (3D) approaches.

MATERIALS AND METHODS

The local ethics committee approved the study, and informed consent was obtained from all patients. Fifty patients underwent coronary CT angiography (heart rate range, 45-103 beats per minute). Raw data from helical CT and electrocardiography (ECG) were saved in a combined data set. Retrospectively ECG-gated images were reconstructed at preselected phases (50% and 80%) of the cardiac cycle. A 3D voxel-based approach with cardiac phase weighting was used for reconstruction. Testing for correlation between heart rate, cardiac phase reconstruction window, and image quality was performed with Kruskal-Wallis analysis. Image quality (freedom from cardiac motion-related artifacts) was referenced against findings at conventional angiography in a secondary evaluation step. Regression analysis was performed to calculate heart rate thresholds for future beta-blocker application.

RESULTS

A significant negative correlation was observed between heart rate and image quality (r = 0.80, P < .001). Motion artifact-free images were available for 44 (88%) patients and were achieved consistently at a heart rate of 80 or fewer beats per minute (n = 39). Best image quality was achieved at 75 or fewer beats per minute. Segmental analysis revealed that 97% of arterial segments (diameter > or = 1.5 mm according to conventional angiography) were assessable at 80 or fewer beats per minute. Premature ventricular contractions and rate-contained arrhythmia did not impede diagnostic assessment of the coronary arteries in 10 (83%) of the 12 patients affected.

CONCLUSION

Motion-free coronary angiograms can be obtained consistently with 16-detector row CT scanners and adaptive multicyclic reconstruction algorithms in patients with heart rates of less than 80 beats per minute.

[Evaluating multislice computed tomography for imaging coronary atherosclerosis]

PURPOSE

The purpose of this study was the evaluation of multidetector-row computed tomography (MDCT) for the assessment of atherosclerotic coronary artery vessel wall changes.

METHODS

In an ex vivo study, 17 human hearts were scanned with MDCT and results were compared to histopathology. Morphologic imaging criteria of MDCT for various plaque-types were developed. In a following in vivo study, 94 coronary MDCT angiograms (MDCTA) of patients with suspected coronary artery disease (CAD) were reviewed retrospectively, assessing the diagnostic value of the coronary MDCTA, and determining the number and correlations of the various plaques types as described in the ex vivo study. Additionally, volumetry of calcified and noncalcified plaque components was performed.

RESULTS

In the ex vivo study, MDCT showed a high sensitivity for calcified and non-calcified plaques. Comparing the results with histopathology, characteristic image criteria could be determined for lipid-rich, fibrous and calcified plaque components. Reviewing the contrastenhanced in-vivo MDCT coronary angiographies, presence of noncalcified plaques was proven in 38% of the patients. In 5 patients with a calcium score of 0, presence of coronary atherosclerosis was proven in the contrastenhanced scan.

CONCLUSIONS

MDCT is able to differentiate various plaque components in an ex vivo setting as well as invivo. Contrastenhanced MDCT of the coronary arteries allows for the detection of noncalcified plaques. In vivo volumetry of noncalcified plaques is feasible.

Ethical issues for invasive cardiologists: Society for cardiovascular angiography and interventions

In view of the major impact of medical economic forces, rapidly changing technology, and other pressures on invasive cardiologists, the Society for Cardiovascular Angiography and Interventions determined that a statement of the ethical issues confronting the modern invasive cardiologist was needed. The various conflicts presented to the cardiologist in his or her roles as practicing clinician, administrator of the catheterization laboratory, educator, or clinical researcher were reviewed. In all instances, the major concern was determined to be the welfare of the patient no matter how forceful the pressures from various outside force or concerns for personal advancement might be.

Complementary results of computed tomography and magnetic resonance imaging of the heart and coronary arteries: a review and future outlook

MR and CT imaging are emerging as promising complementary imaging modalities in the primary diagnosis of CAD and for the detection of subclinical atherosclerotic disease. For the detection or exclusion of significant CAD, both cardiac CT (including coronary calcium screening and non-invasive coronary angiography), and cardiac MRI (using stress function and stress perfusion imaging) are becoming widely available for routine clinical evaluation. Their high negative predictive value, especially when combining two or more of these modalities, allows the exclusion of significant CAD with high certainty, provided that patients are selected appropriately. The primary goal of current investigations using this combined imaging approach is to reduce the number of unnecessary diagnostic coronary catheterizations, and not to replace cardiac catheterization altogether. For the diagnosis of obstructive coronary atherosclerosis and for screening for subclinical disease, CT and MRI have shown potential to directly image the atherosclerotic lesion, measure atherosclerotic burden, and characterize the plaque components. The information obtained may be used to assess progression and regression of atherosclerosis and may open new areas for diagnosis, prevention, and treatment of coronary atherosclerosis. Further clinical investigation is needed to define the technical requirements for optimal imaging, develop accurate quantitative image analysis techniques, outline criteria for image interpretation, and define the clinical indications for both MR or CT imaging. Additional studies are also needed to address the cost effectiveness of such a combined approach versus other currently available imaging modalities.

Effectiveness and safety of manual hemostasis facilitated by the SyvekPatch with one hour of bedrest after coronary angiography using six-French catheters

Manual hemostasis facilitated by a SyvekPatch with 1 hour of bedrest after coronary angiography using 6Fr catheters was evaluated in a study of 200 patients. There were no major adverse events and 2% minor adverse events, all of which were managed successfully with additional bedrest of 1 to 2 hours. The findings suggest that the 1-hour bedrest protocol using the SyvekPatch is safe and effective in low-risk patients.

Rotational X-ray coronary angiography

We designed and implemented a digital flat-panel-based rotational X-ray coronary angiography technique hypothesizing that luminal disease could be identified with less radiation exposure and contrast usage compared to conventional angiography. Individuals scheduled for diagnostic coronary angiography were prospectively enrolled. In addition to conventional acquisitions in standard planes, subjects underwent one additional left coronary artery (LCA) or right coronary artery (RCA) rotational (spin) acquisition using a predefined trajectory. Radiation exposure and contrast volume were recorded for each run. Seventy-five subjects were enrolled. When compared with standard five-view cine acquisition, LCA spin angiography with one cranial and one caudal run resulted in 34.38% +/- 13.65% less radiation, 18.98% +/- 4.97% less contrast, and comparable assessment of stenosis severity. One spin acquisition compared with three standard cine acquisitions for RCA angiography resulted in 59.31% +/- 29.07% lower radiation, no significant change in contrast, and comparable assessment of stenosis severity. Rotational X-ray coronary angiography provides comparable visualization of coronary anatomy compared with traditional nonrotational coronary angiography with significantly less radiation exposure and contrast volume.

Fluoroscopic image quality in the film and filmless eras: a standardized comparison performed in coronary interventional facilities

One hundred and one coronary interventional systems (45 primarily film-based predigital systems, labeled group 1; and 56 filmless digital systems, labeled group 2) were examined over a 5-year period using a standardized imaging phantom. Fluoroscopic image intensifier input dose, high-contrast spatial resolution, low-contrast sensitivity, and static and dynamic low-contrast resolution were assessed under several conditions simulating patient body habitus. The distribution of spatial resolutions in group 2 facilities favored higher line pair resolution over group 1 (P = 0.01). Contrast sensitivity (smallest-diameter hole visualized) was consistently and significantly enhanced with the use of digital imaging under both medium (P = 0.001) and large (P = 0.002) patient habitus simulations. Low-contrast video resolution (number of wires seen) under static (P = 0.007) and dynamic (P = 0.002) conditions was also improved in the digital facilities. However, image intensifer input dose was similar in both groups (group 1 median dose, 23 mR/min; group 2 median dose, 26 mR/min; P = NS). Fluoroscopic spatial resolution in digital filmless laboratories was significantly improved when compared to predigital, film-based laboratories. Low-contrast sensitivity and low- contrast video resolution under both static and dynamic conditions were also significantly improved in the digital laboratories. Notably, the input dose of radiation required to produce these improved fluoroscopic images was similar between groups.

Assessing quality in the cardiac catheterization laboratory

Quality assurance and improvement have increasingly been the focus of health care providers, third-party payers, and patients. Because cardiovascular procedures are common, easily identifiable with claims data, and account for a relatively large proportion of health care expenditures, particular attention has been paid to quality assurance in the setting of the diagnostic and interventional cardiac catheterization laboratory. The structure, process, and outcomes domains of quality measurement in the interventional laboratory involve the maintenance of volume standards, the availability of surgical backup, consistent tracking of procedural outcomes and complications so they can be compared with national standards, and the application of evidence-based therapy. Quality assurance i the diagnostic laboratory revolves around the clinical proficiency of the operators, the maintenance and management of catheterization laboratory equipment, and the presence of a continuous quality improvement program. The evolution of interventional equipment and techniques along with the establishment of national registries has led to a gradual improvement in the quality of percutaneous coronary intervention. Given the dynamic nature of cardiology, adaptable quality assurance and quality improvement programs will remain the foundation of successful catheterization labs.

Reduction in vascular access site bleeding in sequential abciximab coronary intervention trials

We analyzed vascular access site bleeding from the EPIC, EPILOG, and EPISTENT trials to quantify the decrease in vascular bleeding complications in these three trials, especially those attributable to abciximab. The incidence of combined major and minor vascular access site bleeding in nonabciximab (heparin plus placebo) patients progressively decreased from EPIC (8.2%) to EPILOG (2.9%) to EPISTENT (1.7%; P < 0.001). Combined major and minor vascular access site bleeding in abciximab (heparin plus abciximab) patients decreased from EPIC (20%) to EPILOG (5.8%) to EPISTENT (2.2%; P < 0.001). There were more major vascular access site bleeds with abciximab compared to placebo in EPIC (odds ration 3.2; P < 0.001) but not in EPILOG or EPISTENT. Modified abciximab and heparin dosing and improved vascular access site management strategies have decreased the risk of vascular access bleeding during coronary intervention and have essentially eliminated the excess access site bleeding associated with abciximab.