[Evaluation of hospital admissions for angiocardiographic procedures in patients with cardiovascular disease (DRG 124): a retrospective study in four Rome hospitals (Italy)]. / Analisi dei ricoveri ordinari finalizzati all'esecuzione di esami angiocardiografici per patologie cardiovascolari attributi al DRG 124: studio retrospettivo in quattro ospedali di Roma.

The aim of this study was to evaluate hospital admissions assigned to DRG 124 because attributable to the diagnosis and therapy of cardiovascular diseases and the performance of an angiocardiographic exam with contrast and/or cardiac catheterism. As part of the hospital activity evaluations performed by the Lazio Region between 1 January 2002 and 30 June 2005 in four healthcare institutions in the Rome metropolitan area, 136 admissions assigned to DRG 124 were evaluated. An evaluation grid was used to verify information recorded in the hospital discharge forms and hospital medical records for these admissions. Overall 89% (121/136) of medical records were found to be incongruent with the corresponding hospital discharge form and 53% of admissions (72/136) were reassigned a different DRG after evaluation. In most of these cases (n=54; 76%) the selection of a different DRG was required because an incorrect main diagnosis had originally been chosen. The mean relative weight of admissions in which DRG reassignment was required was 1.4189 before recoding and 0.7545 after these were assigned to a new DRG.

Determination of ventricular ejection fraction: a comparison of available imaging methods. The Cardiovascular Imaging Working Group.

Knowledge of left ventricular ejection fraction has been shown to provide diagnostic and prognostic information in patients with known or suspected heart disease. In clinical practice, the ejection fraction can be determined by using one of the five currently available imaging techniques: contrast angiography, echocardiography, radionuclide techniques of blood pool and first pass imaging, electron beam computed tomography, and magnetic resonance imaging. In this review, we discuss the clinical application as well as the advantages and disadvantages of each of these methods as it relates to determination of ventricular ejection fraction.

A comparison of low- with high-osmolality contrast agents in cardiac angiography. Identification of criteria for selective use.

BACKGROUND: Controversy exists as to whether low-osmolality radiographic contrast agents, which have less detrimental pharmacological effects but are considerably more expensive than high-osmolality agents, should be used universally or only for selected high-risk patients. METHODS AND RESULTS: A randomized, double-blind study was used to compare the frequency and severity of adverse events in 2245 consecutive patients undergoing diagnostic cardiac angiography. Two thousand one hundred sixty-six patients were successfully randomized to either iohexol, a low-osmolality contrast agent, or diatrizoate (as Hypaque 76), a high-osmolality agent. The end point event included clinically important adverse events (which jeopardized the patient or required aggressive treatment), contrast agent-related procedure abbreviations, and conversion to open-label contrast agent. Clinically important end point events were associated with increased age, New York Heart Association functional class, left ventricular end-diastolic pressure, arteriovenous oxygen difference, severity of coronary artery disease, and history of a previous reaction to contrast agent. End point events were less frequent in patients receiving iohexol (2.6% versus 4.6%; adjusted odds ratio, 1.59; 95% confidence interval, 0.97-2.60; P = .07). The difference in event frequency between iohexol and diatrizoate was confined to the highest-risk quartile of the patient population. An algorithm was developed to classify patients as being at high or low risk for an event based on patient age, New York Heart Association class, history of a prior contrast reaction, and left ventricular end-diastolic pressure. Application of this algorithm for selective use of low-osmolality agents only for high-risk patients to a theoretical population of 1000 patients reduced contrast agent costs 66% without increasing the frequency of contrast agent-related adverse events. CONCLUSIONS: The advantages of low-osmolality contrast agents are clinically important in patients with severe heart disease but are not in less ill patients. Universal use of low-osmolality agents for cardiac angiography in an unselected population is not necessary. Appropriately guided selective use of low-osmolality contrast agents is feasible and has the potential to reduce cost substantially without compromising safety or effectiveness.

Net costs from three perspectives of using low versus high osmolality contrast medium in diagnostic angiocardiography.

OBJECTIVES: We conducted an economic analysis to assess the extent to which a reduction in adverse drug reactions induced by low osmolality compared with high osmolality contrast media during diagnostic angiocardiography would result in savings to hospitals, society and third-party payers that would offset the substantially higher price of low osmolality contrast medium. BACKGROUND: Substitution of low osmolality for high osmolality contrast media in the approximately 1 million diagnostic angiocardiographic procedures performed each year in the United States could substantially increase health care costs. Cost-effectiveness estimates should include savings that might occur through reduced costs of managing adverse drug reactions. METHODS: In a randomized clinical trial of 505 persons under-going diagnostic angiography with either high osmolality or low osmolality contrast medium, we measured and compared 1) material costs of contrast media, and 2) costs from three perspectives of incremental resources used to manage contrast-related adverse drug reactions. We also performed sensitivity analyses to examine the effect of different assumptions with regard to relative risk, absolute risk and costs of adverse drug reactions on estimates of net cost of use of high osmolality and low osmolality contrast media. RESULTS: One-hundred thirty-seven (54.2%) of 253 patients receiving high osmolality contrast medium and 44 (17.5%) of 252 patients receiving low osmolality contrast medium experienced adverse drug reactions. The average cost (from society's perspective) of resources used to manage adverse drug reactions per patient undergoing angiography was significantly (p = 0.0001) greater for high osmolality (mean $249) versus low osmolality (mean $92) contrast medium. Differential costs (from the hospital's perspective) were $67 greater for high osmolality contrast medium. Charges and professional fees (from the payer's perspective) were $182 greater for high osmolality (mean $312) than for low osmolality (mean $130) contrast medium (p = 0.42, NS). The higher differential and average costs of managing adverse drug reactions with high osmolality contrast medium offset 33% and 75%, respectively, of the $207 difference in mean material costs, but these estimates are sensitive to infrequent high cost cases. CONCLUSIONS: Although low osmolality contrast medium is not cost-saving in diagnostic angiocardiography, its higher price is partially offset by lower management costs of adverse drug reactions. The cost offset for the hospital is lower than that for society and may not be realized by third-party payers. These methods and results may be useful in establishing clinical and payment guidelines for use of alternative contrast media in diagnostic angiocardiography.

Risk stratification in survivors of acute myocardial infarction: routine cardiac catheterization and angiography is a reasonable approach in most patients.

Noninvasive risk assessment in survivors of AMI can effectively subdivide patients into groups with differing risk profiles after hospital discharge, but some patients at risk for late death or recurrent AMI may be incorrectly identified; data from cardiac catheterization and angiography provide complementary and generally more powerful prognostic information. Many patients may derive particular benefit from early cardiac catheterization and angiography, including: (1) patients with AMI complicated by recurrent myocardial ischemia, congestive heart failure, and/or complex ventricular arrhythmias; (2) patients with abnormal or inconclusive results of noninvasive testing or those patients unable to perform an exercise test; (3) patients with abnormal left ventricular global systolic function and those with increased left ventricular end-systolic volume; (4) "young" patients (younger than 50 years of age?); (5) older patients (older than 65 to 70 years of age?); (6) patients with non-Q wave AMI; and (7) patients who are receiving thrombolytic therapy. Performance of early cardiac catheterization and angiography in virtually all survivors of AMI, with selective use of appropriate noninvasive tests, may provide a more efficacious means of risk assessment after AMI; if all tests are performed judiciously, the cost of such an approach need not be excessive. A combination of invasive and selected noninvasive tests probably provides optimal information. The risks to the routine performance of diagnostic cardiac catheterization and angiography in all survivors of AMI are: (1) adequate care and attention may not be paid to proper performance of the procedure(s) and to detailed and proper analyses of the data; (2) the need for additional noninvasive testing in selected patients may be ignored; and most importantly, (3) premature or unnecessary revascularization procedures may be performed subsequently. For optimal patient care, the clinician must obtain all necessary data, avoid unnecessary and repetitive tests, know the accuracy of individual tests at his or her own facility, interpret all data in proper context, and then counsel patients objectively about available management strategies. With this approach, all patients who might appropriately benefit from coronary artery revascularization will be correctly identified, and patients who are truly at very low risk (minimal residual coronary artery disease and preserved left ventricular function particularly if associated with a patent infarct-related artery) may be similarly identified and managed appropriately with elimination of unnecessary additional testing and pharmacologic therapy. Finally, whatever approach to risk stratification one chooses for an individual patient, the importance of and the need to correct and/or ameliorate risk factors for coronary artery disease must be recognized and undertaken.

Randomized comparison of the cost and effectiveness of iopamidol and diatrizoate as contrast agents for cardiac angiography.

To evaluate the effectiveness and cost of low osmolarity, nonionic contrast agents for cardiac angiography, 443 patients were randomized to receive either iopamidol or diatrizoate. All adverse events that occurred within 24 h of the procedure were recorded prospectively by study personnel and classified according to previously determined criteria. Major events were defined as life threatening or requiring a procedure to treat, or both. Costs of the catheterization procedure, pharmacy, hospital laboratory and treatment of adverse events were determined on the basis of actual resource use. A total of 20 patients (8.5%) had major and 143 (61%) had minor adverse events with diatrizoate use; 10 patients (4.8%) had major and 53 (25%) had minor adverse events with iopamidol (p = 0.12 for major events; p less than 0.001 for total events). Most adverse events were treated fairly easily and inexpensively. The median overall cost was $186 higher for patients after iopamidol use compared with diatrizoate (p less than 0.0001), but all costs except the cost of the contrast agent were not significantly different between the two groups. Thus, patients who received iopamidol for cardiac angiography had a significantly lower rate of adverse events than those who received diatrizoate, but this difference was achieved at a considerably high overall cost.

[Cost-effectiveness analysis of two-dimensional/Doppler echocardiography, cardiac catheterization and angiography in the diagnosis of congenital heart disease].

To compare the costs and effectivenesses of 2-dimensional/Doppler echocardiography (2D/DE), cardiac catheterization (CC) and angiography (CA) in the evaluation of cardiac anatomy in patients with congenital heart disease, these three kinds of examinations were performed in 100 patients before operation. The 100 patients had 120 separate cardiovascular abnormalities, of which 100 (83.3%) were prospectively identified by 2D/DE. The sensitivity and specificity of 2D/DE were: ASD, 87.9% and 100%; VSD, 97.9% and 96.1%; PDA, 86.7% and 98.2%, Tetralogy of Fallot, 6 of 6 patients; the overall sensitivity and specificity of the less common defects, 31.6% and 95.8%. Ninety-seven (80.8%) were prospectively identified by catheterization. The sensitivity and specificity of catheterization were: ASD, 87.9% and 100.0%; VSD, 80.9% and 94.6%; PDA 93.3% and 96.6%; Tetralogy of Fallot, 6 of 6 patients, the less common defects, 52.6% and 95.5%. Forty-five (81.8%) were prospectively identified by angiography in 55 patients. The sensitivity and specificity of angiography: ASD, 5 of 7 patients, VSD, 88.0% and 94.3%; PDA, 2 of 2 patients; Tetralogy of Fallot, 5 of 5 patients; the less common defects, 68.8% and 100.0%. The economic evaluations were performed. The costs of the depreciation (including equipments and houses), hospital bed, water and electricity, management and staffs' wage were: 2D/DE, RMB 46.09 per patient; catheterization, RMB 314.17 per patient; angiography, RMB 314.17. The ratios of cost to outcome (cost per correct diagnosis) of 2D/DE, CC and CA were: 55.33, 388.82 and 384.07 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

A measure of 2 x 2 association with stable variance and approximately normal small-sample distribution: planning cost-effective studies.

A measure of 2 x 2 association, Z, is developed having the property that n(Z - Z) has approximately a standard normal distribution, even for quite small sample size. Examples of the use of this variance-stabilizing and normalizing transformation in planning studies of 2 x 2 association are presented. Studies of the association between coronary artery disease and exercise stress test results are used to illustrate these methods.