| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 1995;92:741-747.)
© 1995 American Heart Association, Inc.
Articles |
In-Hospital Cost of Percutaneous Coronary Revascularization
Critical Determinants and Implications
From the Departments of Cardiology (S.G.E., K.J.B., N.O., G.L.H., J.G., E.J.T.) and Biostatistics (D.P.M., M.K.), The Cleveland Clinic Foundation, Cleveland, Ohio.
Correspondence to Stephen G. Ellis, MD, The Cleveland Clinic Foundation, 9500 Euclid Ave, F-25, Cleveland, OH 44195.
 |
Abstract |
|---|
 Top Abstract IntroductionMethods Results Discussion References |
|---|
Background Hospital charges associated with percutaneous transluminal coronary revascularization (PTCR) in the United States exceeded $6 billion in 1994 and are likely to be constrained in some manner in the near future. Despite this high cost to the public, little is known about the major determinants and sources of variability of PTCR.
Methods and Results From a consecutive series of 1258 procedures
with attempted PTCR at a single tertiary referral center, we
analyzed 65 clinical, angiographic, physician, and outcome
variables as potential correlates of total (hospital and physician)
cost. Direct and indirect costs, both hospital and physician, were
determined on the basis of resource utilization using "top-down"
methodology and were available for 1237 procedures (1086 patients)
(98.3%). Mean (±SD) patient age was 62±11 years, 76% were male,
3%
had acute myocardial infarction, 71% had unstable angina, 58% had
multivessel disease, left ventricular ejection fraction was
54±12%, 26% had use of at least one nonballoon
revascularization device, and median length of stay
was 4.4 days. Procedural success was obtained in 89%, and major
complications (death, bypass surgery, or Q-wave myocardial infarction)
occurred in 3.8%. The median cost was $9176, but it was asymmetrically
distributed, and the interquartile and total ranges were wide ($7333 to
$13 845 and $3422 to $193 474, respectively). Analyses of
independent correlates of cost and loge(cost)
were performed using multivariate linear regression in
training and test populations. Modeling found 15 independent
preprocedural correlates of loge(cost)
(R2=.37) and 23 overall correlates
(R2=.65), excluding length of stay per se.
Addition of length of stay to the model increased the explanatory power
of the model to R2=.82. Preprocedural
variables most predictive of
loge(cost) included presentation with
acute myocardial infarction, decision delay (>48 hours between
admission and diagnostic angiography and/or >24 hours
between angiography and intervention), weekend delay, use of
intra-aortic balloon counterpulsation, intention to stent,
creatinine 
2.0 mg%, and lesion complexity (modified
American College of Cardiology/American Heart
Association score) (all P<.001). In the model that included
postprocedural variables as well, length of stay, noncardiac death,
urgent bypass surgery, use of the Rotablator, Q-wave myocardial
infarction, rise in creatinine 1.0%, and blood
product transfusion were all strong independent correlates of
loge(cost) (P<.001).
Conclusions The range of total hospital costs associated with percutaneous intervention is extraordinarily wide. Baseline patient characteristics account for nearly half of the explained variance, but procedural complications and system delays account for much of the remainder. Quantification of the determinants of cost may promote more economically efficient care in the future.
Key Words: angioplasty • coronary disease • cost analysis
|
Introduction |
|---|
|
TopAbstractIntroductionMethods Results Discussion References |
|---|
Coronary revascularization using balloon angioplasty was introduced in the United States in 1978. Remarkable growth of this procedure has ensued, in part because of its capacity to limit the symptoms of angina,1 and
430 000 related procedures
were predicted to be performed in 1994.2 With an expected
hospital charge of $15 000 per procedure,3 a charge of
more than $6 billion to the already sizable national medical bill will
result. Despite this enormous expense, the variance and determinants of
the true hospital cost of these procedures are poorly understood. With
increasing constraints on spending, we sought to identify and model the
critical determinants of cost of balloon angioplasty and related
procedures. |
Methods |
|---|
|
TopAbstractIntroductionMethods Results Discussion References |
|---|
Patient Population
From November 1, 1992, through June 31, 1993, consecutive patients undergoing attempted treatment with any form of percutaneous mechanical coronary revascularization (balloon angioplasty, directional atherectomy, high-speed rotational atherectomy, extraction atherectomy, laser angioplasty, or stent implantation) at a single tertiary referral center were eligible for study entry. Baseline, treatment, and outcome data for all such patients were recorded prospectively and entered into an interventional database with sophisticated data validation, consistency checks, and other quality control assurance measures. All charts were subjected to an independent audit at or after the time of hospital discharge to ensure accurate coding of variables. System delays were identified and recorded prospectively by a single registered nurse. These patients were treated by 1 or more of 11 staff interventional cardiologists who performed 71 to 446 interventions annually and also performed other clinical and research duties to various degrees. Cost, clinical, and system delay data were available for 1237 of the 1258 eligible procedures (1086 patients; 98.3%).
Method of Determining Costs
Cost data were downloaded from
the hospital cost accounting
system (Transition System, Inc), a commercially available system that
calculates total (hospital and physician) cost on a per-patient
basis.4
Hospital costs may include disposable supplies, nonphysician labor, and indirect costs such as major capital depreciation and overhead. Disposable supply costs are based on actual acquisition costs. Nonphysician labor (nursing, fellows, secretaries, etc), including benefits, are obtained directly from actual salaries and apportioned as 55% variable (on the basis of duration of time spent in the catheterization laboratory, in intensive care, and on regular nursing floors) and 45% fixed per procedure. Indirect hospital costs (ie, major capital depreciation, overhead) are allocated on the basis of factors such as patient volume or square footage.
Direct physician costs are based on actual salaries and benefits of staff physicians as well as some nonprofessional staff. These costs are assigned on the basis of average labor time estimates for CPT codes. Indirect physician costs (ie, overhead, insurance) are also allocated on the basis of patient volume or square footage. Adjustment for the medical component of the Consumer Price Index was not applied because of the short time period studied and the minor contribution of inflationary change relative to other costs.
Statistical Methodology
Data are described by mean±SD,
median and interquartile ranges,
or percent, as appropriate.
Regression models of both cost and loge(cost) were built with a randomly selected training set of 60% of procedures. Forward and backward stepwise techniques were used to determine which variables made a significant additional contribution to the models. A type I error rate of 0.01 was used to protect against overfitting. Two-way interactions and some nonlinear terms were also considered after the significant main effects were determined.
Three distinct models of cost were developed: a predictive model using only data available at the beginning of the procedure and two explanatory models using all variables (one using length of stay as an independent variable and the other model excluding this parameter). After the models were validated at each step of the modeling process with the remaining 40% of the data, they were refit with the full data set.
Because of the nongaussian distribution of cost and the skewed residual from a linear model of untransformed cost data, modeling of loge(cost) was considered to be the preferred analysis. Only selected data regarding simple cost are presented. The independent contribution of each variable in the models was calculated and was also expressed as the percent cost effect (% mean increase in cost for a patient with a given characteristic compared with that of another otherwise identical patient).
The 1237 procedures were performed on 1086 patients. For those patients with two procedures, the residual loge(cost) of the first procedure was not at all predictive of the residual loge(cost) of the second procedure (r=-.01, P=.92). Therefore, the use of multiple procedures from the same individual was allowed for the multiple regression models, and the standard errors and probability values from these models do not require adjustment.
All modeling was performed with SAS software.
Definitions
Most variables analyzed have been defined
previously5 or need no definition. Those that are new to
the interventional cardiology literature or
particularly germane to this study are listed below.
Delayed decision was defined as a delay >48 hours between the time of hospitalization and the decision whether or not the patient should undergo diagnostic angiography and/or delay of >24 hours between the time of diagnostic angiography and intervention due to uncertainty as to whether or not the patient should be treated with percutaneous revascularization.
Lesion morphology was defined as the most complex (modified American College of Cardiology/American Heart Association lesion classification6 ) lesion with attempted treatment. For numerical analysis, type C lesions were given 3 points, type B2 lesions were given 2 points, and types B1 and A lesions were coded with 1 point.
Number of diseased vessels was defined as the number of major
epicardial vessels or bypassable branches thereof (left anterior
descending, left circumflex, and right coronary arteries;
maximum of three) with 50% diameter stenosis (measured with
calipers).
Scheduling delay was defined as a delay of >24 hours between the time a patient already in the hospital was referred for treatment and the time the treatment was performed (due to specific physician unavailability or the laboratory schedule being full).
Weekend delay was defined as a scheduling delay solely because the catheterization laboratory is not routinely open for elective procedures on weekends and major holidays.
The following variables not shown in the accompanying tables were also analyzed but did not correlate with cost: age, arteriovenous fistula, evaluation as nonbypassable, heart rate, hematoma >15 cm, New York Heart Association heart failure class, physician provider, prior infarction, pseudoaneurysm, retroperitoneal hemorrhage, sex, stroke, systolic blood pressure, and unstable angina.
|
Results |
|---|
|
TopAbstractIntroductionMethods Results Discussion References |
|---|
Patient Characteristics
Selected characteristics of the patients studied are enumerated in Table 1
. Patients were in many ways typical of other
groups undergoing coronary intervention,7 8
although the high incidence of unstable angina and use of nonballoon
technologies are notable. The training and test samples were not
significantly different for any variable tested. In-hospital
clinical outcomes are described in Table 2 and are
typical of those currently reported.7 8
|
|
Costs
The total hospital and physician costs had a
nongaussian
distribution with a median of $9176, mean of $13 071±12 667,
interquartile range of $7333 to $13 845, and total range of $3422 to
$193 474. The low-end costs result from unsuccessful, uncomplicated,
and therefore outpatient procedures, wherein a minimum of resources was
used. A breakdown of costs by resource center is provided in Table
3.
|
Correlates and Models of Cost
Preprocedural Correlates
of Loge(cost)
The independent preprocedural
correlates of
loge(cost) are enumerated in Table 4. This
model accounted (R2) for
37% of the total variation in cost. Of this, 31% was described by
clinical (notably treatment for acute myocardial infarction,
intra-aortic balloon counterpulsation, and creatinine 2.0
mg%) or angiographic (lesion complexity) variables, an additional
6% by hospitalization or decision delays, and 5% by the device
approach chosen (stenting, Rotablator, or transluminal extraction
catheter or directional atherectomy). No physicians5 were
identified with significantly higher or lower costs.
|
Overall Correlates of
Loge(cost)
The independent correlates of
loge(cost) in
the two explanatory models of cost are shown in Tables 5 and
6. Inclusion of postprocedural variables such as
complications increased the explanatory power of the model considerably
(to R2=.82 if length of stay is included and to
R2=.65 if length of stay is not included).
Postprocedural variables that made substantial contributions to
these models included length of stay per se, noncardiac death, rise in
creatinine, urgent bypass surgery, blood product
transfusion, and resultant Q-wave myocardial infarction.
|
|
Many variables
were, by themselves, also correlated with
loge(cost) but were dropped from the models
because they were highly correlated with other variables that were
more closely correlated with loge(cost). An
example of this problem of multicollinearity can be seen with the
variable of unstable angina. As a single variable, unstable
angina was highly correlated with loge(cost)
(P<.001). However, unstable angina was correlated also with
heparin use before treatment (perhaps reflecting particularly unstable
symptoms) (r=.16, P<.001) and recent myocardial
infarction (r=.15, P<.001), each of which was
more strongly correlated with increased
loge-(cost). In multivariate
testing, the variable of unstable angina was therefore not a
significant correlate of cost (Table 4
). In a somewhat
analogous
manner, in the full explanatory model wherein the variable length
of stay was included (Table 6), many variables correlated with
length of stay and with loge(cost) that appeared
in the model when length of stay was not tested (Table 5) were
dropped
when length of stay was included in the model (Table 6).
Examples of
these dropped variables include postprocedural non–Q-wave
myocardial infarction, large hematoma, and weekend delay. Data in
Tables 5 and 6 therefore define variables most
helpful in
explaining the causes of increased cost, whereas data in Table
4 define
variables useful in predicting cost. All three of these
analyses are important in understanding the determinants of
cost for these procedures.
|
Discussion |
|---|
|
TopAbstractIntroductionMethods Results Discussion References |
|---|
The need to restrain the rate of increase of medical costs in the United States is well recognized, and high-volume, high-cost procedures such as coronary angioplasty and related techniques are obvious targets for scrutiny. Unfortunately, the determinants of cost with these procedures are poorly understood.
Most studies of this problem to date have dealt with hospital charges and charge ratios, not cost,9 10 11 12 13 14 largely because the charges are much more readily available and true costs not easily derived. However, internal cost shifting and cross-subsidization, such as "marking up" the charges for laboratory tests to compensate for lower reimbursement of other items,15 are common and may obfuscate the true determinants of cost. In such a study of 2392 patients from a single institution, Weintraub et al16 found that while postprocedural outcomes such as death, infarction, emergency surgery, and length of stay together were quite well correlated with charges, the variables available before the procedure explained <5% of the charge variance. One would infer from these data that the best way (and the only way from these data) to reduce resource utilization would be to decrease the ischemic complications of angioplasty and related techniques. In this study, detailed clinical characteristics, system inefficiencies (eg, delays in decision making, weekend admissions), and nonischemic complications were not examined. Topol et al3 described considerable geographic and institution type (training program versus community hospital) differences in charges from a large insurance database beyond what might be expected from differences in major procedural complications, but the data set was limited in the potential covariates available, and the determinants of charges could not be fully explored. Dick and colleagues13 specifically examined the added charges of new device therapies and found significant increments over balloon angioplasty with both new modalities examined (elective stent placement, +$6354, P<.001, and directional atherectomy, +$2368, P<.01). The incremental costs with directional atherectomy were substantiated in the randomized multicenter CAVEAT I trial14 but were challenged by Cohen et al17 in an observational series from a single institution. Cohen et al did note, however, a substantial increase in cost with stent implantation compared with balloon angioplasty alone.
The data reported here extend prior observations by noting, in
particular, (1) the predictive information contained in variables
available before the procedure, which explains nearly one third of the
variance of cost (Table 4); (2) the importance of
system-related
problems, such as delays in therapy due to lack of availability of some
hospital services on weekends or protracted decision-making (Table
4);
and (3) the high cost of noncardiac complications such as progressive
renal dysfunction, blood transfusion, and peripheral
vascular complications (Table 5). The lesser correlation with
preprocedural data found in prior reports may derive from the
relatively weak correlation between cost and common variables such
as unstable angina and left ventricular ejection fraction.
Variables such as baseline creatinine and the need for
balloon counterpulsation or heparin therapy appear to be better markers
for resource consumption. In addition, other variables found to be
important in this analysis, such as weekend delays, blood
product usage, and need for vascular surgical repair of access
site–related complications, may not have been considered in previous
studies.
Implications for Cost Containment
The message from this
analysis, and to a certain extent
from others,16 is that a reduction in in-hospital
complications should lead to a corresponding reduction in
hospitalization cost. A substantial literature describes the
complications of balloon
angioplasty18 19 20 and newer
devices,21 22 23 24 25 26
yet it is not at all certain whether use of
new nonballoon technologies will decrease complications for most
patients.16 Paradoxically, higher-than-standard doses of
heparin27 and also use of more potent antiplatelet
agents28 have recently been reported to reduce the
ischemic complications of angioplasty, yet they also appear to
be associated with increased bleeding,28 29 so their
net
effect on cost is uncertain.
A recent analysis from the EPIC investigators suggests that, discounting the cost of 7E3 itself, the cost effects from the reduction in ischemic events and increase from bleeding complications with this agent largely cancel each other out.30
Vascular "plugs" may have a role in reducing bleeding complications, but most reports suggest only a reduction in time to ambulation.31 Finally, the use of nonionic contrast has been touted as a means to reduce postprocedure renal insufficiency, but this remains highly controversial,32 33 and nonionic contrast itself is not inexpensive.
One simple way to reduce costs would be to refrain from treating high-risk patients (acute myocardial infarction, poor renal function, multivessel disease, diabetes). Few substantive data are available to determine whether or not percutaneous revascularization is of clinical benefit for many of these patients, but it has generally been shown that revascularization tends to be most beneficial for those patients with poor prognosis,34 35 36 37 and this is supported by nonrandomized data comparing percutaneous transluminal coronary angioplasty and medical therapy.38 If revascularization is thought to be needed and percutaneous and surgical options are considered likely to be equally efficacious, costs may well be similar over a follow-up of several years.39 In the current medical-economic climate, if clinical benefit is likely, cost reduction by avoiding patients likely to have high hospital costs would not be palatable to most patients and physicians.
New devices (eg, stents, lasers) and also standard balloon technologies (including guide catheters, wires, etc) themselves directly contribute about 18% of total hospital cost of the procedure (Cleveland Clinic Foundation, unpublished data), and some (eg, lasers) add substantially to indirect cost. The present analysis suggests that per se, the use of the transluminal extraction coronary atherectomy device, stents, the Rotablator, and to a lesser extent, directional atherectomy all add to cost, whether or not procedural complications are considered. Hence, newer and more expensive devices should be used only in situations in which clinical superiority over balloon catheters is expected or if a long-term reduction in cost might be expected (eg, stents40 41 ). Even balloon catheters, however, are expensive ($300 to $750 each). In many countries, this cost is divided among several patients because the device is sterilized and reused, but such use is not approved in the United States. Although this practice is untested, it remains to be seen whether or not reuse of angioplasty equipment would dramatically reduce cost. Preliminary data suggest a longer procedure time and perhaps more complications with reused balloons.42
Finally, this analysis suggests that system delays also contribute greatly to increased costs. It would be prudent to perform a formal cost analysis at individual hospitals to ascertain whether or not a reduction in patient cost could be achieved by opening the catheterization laboratory for routine weekend use. Whether such an approach would outweigh the associated increase in overtime costs and possible reduction in staff morale would need to be established. In addition, incentives or "care paths" to encourage timely decision-making regarding the need for cardiac catheterization and/or intervention might well reduce costs.
Limitations
This study should be viewed in the context of
several limitations.
First, the number of patients studied is somewhat limited and is
derived from the experience of a single institution. These findings
should be compared with those from other institutions, with perhaps
other practice and resource consumption patterns, as they become
available. Second, the study makes no attempt to compare the costs of
percutaneous revascularization with
other forms of therapy or to compare in a randomized fashion one
percutaneous therapy against the next; thus, it is not
a cost-benefit analysis but is rather a cost-minimization
analysis that we hope will provide insight into how costs might
be reduced in a single resource utilization area. Third, the long-term
cost of patient care is not considered, and the possibility that a high
initial expenditure might lead to reduction in subsequent costs should
not be ignored.
Conclusions
The in-hospital costs associated with caring for
patients
undergoing percutaneous
revascularization vary widely and have multiple
correlates. Markers of the severity of cardiac illness, noncardiac
comorbidities, and system delays account for 37% of the total cost
variance, and another 28% results from induced complications. Only
18% of the variance remains unexplained by the models derived from
this analysis. Characterization of the major determinants and
variability of hospital cost for percutaneous
coronary revascularization may translate
into strategies for meaningful reductions in resource utilization.
|
.05,
**PReceived October 25, 1994; revision received February 1, 1995; accepted February 19, 1995.
|
References |
|---|
|
TopAbstractIntroductionMethods Results Discussion References |
|---|
-
Parisi AF, Folland ED, Hartigan P, and Veterans
Affairs ACME Investigators. A comparison of angioplasty with
medical therapy in the treatment of single-vessel coronary
artery disease. N Engl J Med. 1992;326:10-16. [Abstract]
-
Biomedical Business International (4215), 1994.
-
Topol EJ, Ellis SG, Cosgrove DM, Bates ER, Muller DWM,
Schork NJ, Schork MA, Loop FD. Analysis of
coronary angioplasty practice in the United States with an
insurance-claims data base. Circulation. 1993;87:1489-1497.
[Abstract/Free Full Text]
-
Boston, Mass: Transition Systems Inc; 1989.
-
Ellis SG, Vandormael MG, Cowley MJ, DiSciascio G,
Deligonul U, Topol EJ, Bulle TM. Coronary morphologic
and clinical determinants of procedural outcome with angioplasty for
multivessel coronary disease: implications for patient
selection. Circulation. 1990;82:1193-1202.
[Abstract/Free Full Text]
-
American College of
Cardiology/American Heart Association Task Force.
Guidelines for percutaneous transluminal
coronary angioplasty. J Am Coll
Cardiol. 1988;12:529-545. [Medline]
[Order article via Infotrieve]
-
Detre K, Holubkov R, Kelsey S, Cowley M, Kent K,
Williams D, Myler R, Faxon D, Holmes D, Bourassa M, Block P, Gosselin
A, Bentivoglio L, Leatherman L, Dorros G, King S, Galichia J, Al-Bassam
M, Leon M, Robertson T, Passamani E.
Percutaneous transluminal coronary
angioplasty in 1985-1986 and 1977-1981. N Engl
J Med. 1988;318:265-270. [Abstract]
-
Ritchie JL, Phillips KA, Luft HS.
Coronary angioplasty: statewide experience in
California. Circulation. 1993;88:2735-2743.
[Abstract/Free Full Text]
-
van den Brand M, van Halem C, van den Brink F, de
Feyter P, Serruys P, Suryapranata H, Meeter K, Box E, van Dalen FJ.
Comparison of costs of percutaneous transluminal
coronary angioplasty and coronary bypass surgery for
patients with angina pectoris. Eur Heart J. 1990;11:765-771.
[Abstract/Free Full Text]
-
O'Keefe JH Jr, Gernon C, McCallister BD, Ligon RW,
Hartzler GO. Safety and cost effectiveness of combined
coronary angiography and angioplasty. Am Heart
J. 1991;122:50-54. [Medline]
[Order article via Infotrieve]
-
Bell MR, Berger PB, Menke KK, Holmes DR Jr.
Balloon angioplasty of chronic total coronary artery
occlusions: what does it cost in radiation exposure, time and
materials? Cathet Cardiovasc Diagn. 1992;25:10-15. [Medline]
[Order article via Infotrieve]
-
van den Brand M. Utilization of coronary
angioplasty and cost of angioplasty disposables in 14 western European
countries: European Angioplasty Survey Group. Eur Heart
J. 1993;14:391-397.
[Abstract/Free Full Text]
-
Dick RJ, Popma JJ, Muller DW, Burek KA, Topol EJ.
In-hospital costs associated with new
percutaneous coronary devices. Am
J Cardiol. 1991;68:879-885. [Medline]
[Order article via Infotrieve]
-
Topol EJ, Leya F, Pinkerton CA, Whitlow PL, Hofling B,
Simonton CA, Masden RR, Serruys PW, Leon MB, Williams DO, King SB, Mark
DB, Isner JM, Holmes DR, Ellis SG, Lee KL, Keeler G, Berdan LG,
Hinohara T, Califf RM, on behalf of the CAVEAT Study Group. A
comparison of coronary angioplasty with directional atherectomy
in patients with coronary artery disease. N
Engl J Med. 1993;329:221-227.
[Abstract/Free Full Text]
-
Hlatky MA, Lipscomb J, Nelson C, Califf RM, Pryor D,
Wallace AG, Mark DB. Resource use and cost of initial
coronary revascularization:
coronary angioplasty versus coronary bypass
surgery. Circulation. 1990;82(suppl
IV):IV-208-IV-213.
-
Weintraub WS, Mauldin P, Gilbert S, Hicks F, Canup D.
Pre and post procedure correlates of in-hospital costs of
PTCA. J Am Coll Cardiol. 1994:283A.
Abstract.
-
Cohen DJ, Breall JA, Ho KKL, Weintraub RM, Kuntz RE,
Weinstein MC, Baim DS. Economics of elective coronary
revascularization: comparison of costs and charges
for conventional angioplasty, directional atherectomy, stenting and
bypass surgery. J Am Coll Cardiol. 1993;22:1052-1059. [Abstract]
-
Detre KM, Holmes DR, Holubkov R, Cowley MJ, Bourassa
MG, Faxon DP, Dorros GR, Bentivoglio LG, Kent KM, Myler RK.
Incidence and consequences of periprocedural occlusion: the
1985-1986 National Heart, Lung, and Blood Institute
Percutaneous Transluminal Coronary Angioplasty
Registry. Circulation. 1990;82:739-750.
[Abstract/Free Full Text]
-
Ellis SG, Roubin GS, King SB, Douglas JS Jr, Weintraub
WS, Thomas RG, Cox WR. Angiographic and clinical predictors
of acute closure after native vessel coronary
angioplasty. Circulation. 1988;77:372-379.
[Abstract/Free Full Text]
-
Myler RK, Shaw RE, Stertzer SH, Hecht HS, Ryan C,
Rosenblum J, Cumberland DC, Murphy MC, Hansell HN, Hidalgo B.
Lesion morphology and coronary angioplasty: current
experience and analysis. J Am Coll
Cardiol. 1992;19:1641-1652. [Abstract]
-
Schatz RA, Baim DS, Leon M, Ellis SG, Goldberg S,
Hirshfeld JW, Cleman MW, Cabin HS, Walker C, Staff J, Buchbinder M,
Teirstein PS, Topol EJ, Savage M, Perez JA, Curry RC, Whitworth H,
Sousa JE, Tio F, Almagor Y, Ponder LR, Penn IM, Leonard B, Levine SL,
Fish D, Palmaz JC. Clinical experience with the Palmaz-Schatz
coronary stent: initial results of a multicenter study.
Circulation. 1991;83:148-161.
[Abstract/Free Full Text]
-
George BS, Voorhees WD, Roubin GS, Fearnot NE,
Pinkerton CA, Raizner AE, King SB, Holmes DR, Topol EJ, Kereiakes DJ,
Hartzler GO. Multicenter investigation of coronary
stenting to treat acute or threatened closure after
percutaneous transluminal coronary angioplasty:
clinical and angiographic outcomes. J Am Coll
Cardiol. 1993;22:135-143. [Abstract]
-
Popma JJ, Topol EJ, Hinohara T, Pinkerton CA, Baim DS,
King SB III, Holmes DR Jr, Whitlow PL, Kereiakes DJ, Hartzler GO, Kent
KM, Ellis SG, Simpson JB. Abrupt vessel closure after
directional coronary atherectomy. J Am
Coll Cardiol. 1992;19:1372-1379. [Abstract]
-
Ellis SG, Popma JJ, Buchbinder M, Franco I, Leon MB,
Kent KM, Pichard AD, Satler LF, Topol EJ, Whitlow PL. Relation
of clinical presentation, stenosis morphology, and
operator technique to the procedural results of rotational atherectomy
and rotational atherectomy–facilitated angioplasty.
Circulation. 1994;89:882-892.
[Abstract/Free Full Text]
-
Litvack F, Eigler N, Margolis J, Rothbaum D, Bresnahan
JF, Holmes D, Untereker W, Leon M, Ghazzal Z, Cummins F, Krauthamer D,
Palacios I, Block P, Hartzler GO, O'Neill W, Cowley M, Roubin G, Klein
LW, Frankel PS, Adams C, Goldenberg T, Laudenslager J, Grundfest WS,
Forrester JS, and the ELCA Investigators.
Percutaneous excimer laser coronary
angioplasty: results in the first consecutive 3,000 patients.
J Am Coll Cardiol. 1994;23:323-329. [Abstract]
-
Safian RD, Grines CL, May MA, Lichtenberg A, Juran N,
Schreiber TL, Pavlides G, Meany TB, Savas V, O'Neill WW.
Clinical and angiographic results of transluminal extraction
coronary atherectomy in saphenous vein bypass grafts.
Circulation. 1994;89:302-312.
[Abstract/Free Full Text]
-
Narins CR, Hillegass WB, Nelson CL, Harrington RA,
Phillips HR, Stack RS, Califf RM. Activated clotting
time predicts abrupt closure risk during angioplasty.
J Am Coll Cardiol. 1994;470A. Abstract.
-
The EPIC Investigators. Use of a monoclonal
antibody directed against the platelet glycoprotein
IIb/IIIa receptor in high-risk coronary angioplasty.
N Engl J Med. 1994;330:956-961.
[Abstract/Free Full Text]
-
Popma JJ, Satler LF, Pichard AD, Kent KM, Campbell A,
Chuang YC, Clark C, Merritt AJ, Bucher TA, Leon MB. Vascular
complications after balloon and new device angioplasty.
Circulation. 1993;88:1569-1578.
[Abstract/Free Full Text]
-
Mark DB, Talley JD, Lam LC, Davidson-Ray L, Bowman L.
Reduced restenosis from aggressive platelet
inhibition reduces costs of high risk angioplasty: results from the
EPIC randomized trial. Circulation.
1994;90(suppl I):I-44. Abstract.
-
Sanborn TA, Gibbs HH, Brinker JA, Knopf WD, Kosinski
EJ, Roubin GS. A multicenter randomized trial comparing a
percutaneous collagen hemostasis device with
conventional manual compression after diagnostic
angiography and angioplasty. J Am Coll
Cardiol. 1993;22:1273-1279. [Abstract]
-
Ritchie JL, Nissen SE, Douglas JS Jr, Dreifus LS,
Gibbons RJ, Higgins CB, Schelbert HR, Seward JB, Zaret BL. Use
of nonionic or low osmolar contrast agents in
cardiovascular procedures: American College of
Cardiology Cardiovascular Imaging
Committee. J Am Coll Cardiol. 1993;21:269-273. [Abstract]
-
Deray G, Bellin MF, Boulechfar H, Baumelou B, Koskas F,
Baumelou A, Grellet J, Jacobs C. Nephrotoxicity of contrast
media in high-risk patients with renal insufficiency: comparison of
low- and high-osmolar contrast agents. Am J Nephrol. 1991;11:309-312. [Medline]
[Order article via Infotrieve]
-
Coronary Artery Surgery Study Group.
Coronary Artery Surgery Study (CASS): a randomized trial
of coronary artery bypass surgery: survival data.
Circulation. 1983;68:939-950.
[Abstract/Free Full Text]
-
Alderman EL, Fisher LD, Litwin P, Kaiser GC, Myers WO,
Maynard C, Levine F, Schloss M. Results of coronary
artery surgery in patients with poor left ventricular
function (CASS). Circulation. 1983;68:785-795.
[Abstract/Free Full Text]
-
Lee L, Bates ER, Pitt B, Walton JA, Laufer N, O'Neill
WW. Percutaneous transluminal coronary
angioplasty improves survival in acute myocardial infarction
complicated by cardiogenic shock.
Circulation. 1988;78:1345-1351.
[Abstract/Free Full Text]
-
Grines CL, Browne KF, Marco J, Rothbaum D, Stone GW,
O'Keefe J, Overlie P, Donohue B, Chelliah N, Timmis GC, Vlietstra
RE, Strzelecki M, Puchrowicz-Ochocki S, O'Neill WW, for the Primary
Angioplasty in Myocardial Infarction Study Group. A comparison
of immediate angioplasty with thrombolytic therapy for
acute myocardial infarction. N Engl J Med. 1993;328:673-679.
[Abstract/Free Full Text]
-
Mark DB, Nelson CL, Califf RM, Harrell FE, Lee KL,
Jones RH, Fortin DF, Stack RS, Glower DD, Smith LR, DeLong ER, Smith
PK, Reves JG, Jollis JG, Tcheng JE, Muhlbaier LH, Lowe JE, Phillips HR,
Pryor DB. Continuing evolution of therapy for coronary
artery disease: initial results from the era of coronary
angioplasty. Circulation. 1994;89:2015-2025.
[Abstract/Free Full Text]
-
King SB III, Lembo NJ, Weintraub WS, and the EAST
Investigators. Results from the Emory Angioplasty vs. Surgery
Trial (EAST) compared to the eligible, nonrandomized registry.
J Am Coll Cardiol. 1994:469A. Abstract.
-
Serruys PW, de Jaegere P, Kiemeneij F, Macaya C, Rutsch
W, Heyndrickx G, Emanuelsson H, Marco J, Legrand V, Materne P, Belardi
J, Sigwart U, Colombo A, Goy JJ, van den Heuvel P, Delcan J, Morel M-A,
for the BENESTENT Study Group. A comparison of
balloon-expandable-stent implantation with balloon angioplasty in
patients with coronary artery disease. N
Engl J Med. 1994;331:489-495.
[Abstract/Free Full Text]
-
Fischman DL, Leon MB, Baim DS, Schatz RA, Savage MP,
Penn I, Detre K, Veltri L, Ricci D, Nobuyoshi M, Cleman M, Heuser R,
Almond D, Teirstein PS, Fish RD, Colombo A, Brinker J, Moses J,
Shaknovich A, Hirshfeld J, Bailey S, Ellis S, Rake R, Goldberg S, for
the STRESS Investigators. A randomized comparison of
coronary-stent placement and balloon angioplasty in the
treatment of coronary artery disease. N
Engl J Med. 1994;331:496-501.
[Abstract/Free Full Text]
-
Plante S, Strauss BH, Goulet G, Watson RK, Chisholm RJ.
Reuse of balloon catheters for coronary angioplasty: a
potential cost-saving strategy. J Am Coll
Cardiol. 1994;24:1475-1481.[Abstract]
This article has been cited by other articles:
 |
|
 |
|
  W. J. Kostis, K. Demissie, S. W. Marcella, Y.-H. Shao, A. C. Wilson, A. E. Moreyra, and the Myocardial Infarction Data Acquisition System Weekend versus Weekday Admission and Mortality from Myocardial Infarction N. Engl. J. Med., March 15, 2007; 356(11): 1099 - 1109. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. C. Angus, W. T. Linde-Zwirble, S. W. Tam, J. K. Ghali, M. L. Sabolinski, V. G. Villagra, W. C. Winkelmayer, M. Worcel, and for the African-American Heart Failure Trial (A-He Cost-Effectiveness of Fixed-Dose Combination of Isosorbide Dinitrate and Hydralazine Therapy for Blacks With Heart Failure Circulation, December 13, 2005; 112(24): 3745 - 3753. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. J. Cohen, A. M. Lincoff, T. A. Lavelle, H.-L. Chen, A. Bakhai, R. H. Berezin, D. Jackman, I. J. Sarembock, and E. J. Topol Economic evaluation of bivalirudin with provisional glycoprotein IIB/IIIA inhibition versus heparin with routine glycoprotein IIB/IIIA inhibition for percutaneous coronary intervention: Results from the REPLACE-2 trial J. Am. Coll. Cardiol., November 2, 2004; 44(9): 1792 - 1800. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Cowper, E. D. Peterson, E. R. DeLong, M. B. Wightman, R. P. Wawrzynski, L. H. Muhlbaier, and M. H. Sketch Jr The impact of statistical adjustment on economic profiles of interventional cardiologists J. Am. Coll. Cardiol., November 1, 2001; 38(5): 1416 - 1423. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K T Koch, J J Piek, M H Prins, R J de Winter, K Mulder, K I Lie, and J G P Tijssen Triage of patients for short term observation after elective coronary angioplasty Heart, May 1, 2000; 83(5): 557 - 563. [Abstract] [Full Text]
|
|
|
|
|
|
A. Kastrati, A. Schomig, S. Elezi, J. Dirschinger, J. Mehilli, H. Schuhlen, R. Blasini, and F.-J. Neumann Prognostic Value of the Modified American College of Cardiology/American Heart Association Stenosis Morphology Classification for Long-Term Angiographic and Clinical Outcome After Coronary Stent Placement Circulation, September 21, 1999; 100(12): 1285 - 1290. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. D. Peterson, P. A. Cowper, E. R. DeLong, J. P. Zidar, R. S. Stack, and D. B. Mark Acute and long-term cost implications of coronary stenting J. Am. Coll. Cardiol., May 1, 1999; 33(6): 1610 - 1618. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. G. Ellis, D. Miller, T. F. Keys, K. Brown, R. Ellert, G. Howell, A. M. Lincoff, and E. J. Topol Comparing physician-specific two-year patient outcomes after coronary angiography: Methodologic issues and results J. Am. Coll. Cardiol., April 1, 1999; 33(5): 1278 - 1285. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K T Koch, J J Piek, R J de Winter, K Mulder, C E Schotborgh, J G P Tijssen, and K I Lie Two hour ambulation after coronary angioplasty and stenting with 6 F guiding catheters and low dose heparin Heart, January 1, 1999; 81(1): 53 - 56. [Abstract] [Full Text]
|
|
|
|
|
|
T. Mann, G. Cubeddu, J. Bowen, J. E. Schneider, M. Arrowood, W. N. Newman, M. J. Zellinger, and G. C. Rose Stenting in acute coronary syndromes: a comparison of radial versus femoral access sites J. Am. Coll. Cardiol., September 1, 1998; 32(3): 572 - 576. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 DETERMINANTS OF COST OF PTCA Journal Watch (General), September 1, 1995; 1995(901): 7 - 7. [Full Text]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||