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D S Baim

Publications and source records attributed to D S Baim.

At least 91 records · Page 5Linked to original sources
PubMed1994

Long-term angiographic and clinical outcome after implantation of balloon-expandable stents in aortocoronary saphenous vein grafts.

Balloon angioplasty of aortocoronary saphenous vein graft lesions is associated with high restenosis and clinical event rates. The goal of this multicenter study was to assess long-term angiographic and clinical outcome of patients electively treated with single Palmaz-Schatz stents in aortocoronary saphenous vein grafts. In 198 patients (209 lesions), elective placement of single Palmaz-Schatz stents was attempted. Angiography was performed at baseline, immediately after stent placement, and at 6-month follow-up. Stent placement was successful in 98.5% of patients. One patient (0.5%) had stent thrombosis. Restenosis occurred in 34% (45 of 133) of the restudied lesions. Restenosis was lower in de novo lesions than in restenotic lesions (22% vs 51%, p < 0.001). Ostial lesions had a higher restenosis rate than nonostial lesions (61% vs 28%, p = 0.003). Freedom from death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty was present in 70% of patients. Eighty-two percent of patients with de novo lesions remained event-free at 1 year, whereas only 55% of patients with prior angioplasty were event-free at 1 year (p < 0.001). The use of the Palmaz-Schatz stent for the treatment of focal, de novo, aortocoronary saphenous vein graft lesions is associated with a high procedural success rate, a low angiographic restenosis rate, and low clinical event rates, including the need for repeat revascularization. The results of this study need validation by a prospective randomized trial comparing stent implantation with angioplasty.

Aged↗
PubMed1994

Elevation of the creatine kinase myocardial isoform following otherwise successful directional coronary atherectomy and stenting.

Moderate elevation of creatine kinase (CK) MB isoform is common following otherwise successful percutaneous coronary revascularization, and is frequently interpreted as evidence of a non-Q-wave myocardial infarction. It is not clear, however, whether elevation of CK MB isoform carries sufficient adverse clinical impact to be categorized as a "major" complication. We therefore explored the incidence and clinical consequence of elevation of CK MB isoform in a consecutive series of 565 patients who had otherwise successful directional coronary atherectomy (n = 274) or stenting (n = 291), and were followed for a mean of 2 years. Of this cohort, 11.5% had postprocedure elevation of the CK MB isoform above normal (10 IU/liter). These patients tended to be older and to have undergone atherectomy of a de novo lesion with adverse morphology (thrombus, calcification, eccentricity). Patients with elevation of CK MB isoform following otherwise successful revascularization generally showed no adverse long-term sequelae (death, recurrent myocardial infarction, repeat revascularization) compared with patients without elevation of CK MB isoform. Only 2.3% of the patients who had CK MB isoform release > 50 IU/liter demonstrated a trend (p = 0.08) toward decreased late survival, compared with patients without CK MB isoform elevation. While minor CK MB isoform elevation is common (11.5%) after successful coronary stenting or directional atherectomy, it generally has no adverse clinical consequences, and should not be considered a major complication.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Peripheral vascular complications of directional coronary atherectomy and stenting: predictors, management, and outcome.

The hospital course of 688 patients consecutively treated with directional coronary atherectomy (375 procedures) or Palmaz-Schatz stenting (376 procedures) was evaluated to identify incidence, predictors, and outcome of major vascular complications. Major vascular complications (defined as surgical repair, major hematoma, or bleeding with a > 10-point hematocrit decrease requiring transfusion alone, or nonsurgically managed arteriovenous fistula, pseudoaneurysm, retroperitoneal hematoma or femoral neuropathy) occurred in 11.7% of procedures, and were more common after stenting than after directional coronary atherectomy (16.8% vs 6.7%, p < 0.001). In particular, surgical repair was required after 10.1% of stenting procedures, versus 5.1% of directional coronary atherectomies (p < 0.02). Multivariable analysis identified age > 70 years, coronary stenting, female gender, multiple procedures during the index hospitalization, and a low nadir platelet count as independent predictors of major vascular complications (all p < 0.03). In the stent subgroup, excessive anticoagulation, nadir platelet count, hypertension, and sheath removal protocol (other than a same-day, activated clotting time-guided protocol) were all independent predictors of vascular complications. Thus, the overall risk of vascular complications with new device procedures (stenting, directional atherectomy) is greater than that traditionally seen with balloon angioplasty alone, and is determined by patient-related factors, procedure type, and management parameters.

Aged↗
PubMed1994

A randomized comparison of coronary-stent placement and balloon angioplasty in the treatment of coronary artery disease. Stent Restenosis Study Investigators.

BACKGROUND: Coronary-stent placement is a new technique in which a balloon-expandable, stainless-steel, slotted tube is implanted at the site of a coronary stenosis. The purpose of this study was to compare the effects of stent placement and standard balloon angioplasty on angiographically detected restenosis and clinical outcomes. METHODS: We randomly assigned 410 patients with symptomatic coronary disease to elective placement of a Palmaz-Schatz stent or to standard balloon angioplasty. Coronary angiography was performed at base line, immediately after the procedure, and six months later. RESULTS: The patients who underwent stenting had a higher rate of procedural success than those who underwent standard balloon angioplasty (96.1 percent vs. 89.6 percent, P = 0.011), a larger immediate increase in the diameter of the lumen (1.72 +/- 0.46 vs. 1.23 +/- 0.48 mm, P < 0.001), and a larger luminal diameter immediately after the procedure (2.49 +/- 0.43 vs. 1.99 +/- 0.47 mm, P < 0.001). At six months, the patients with stented lesions continued to have a larger luminal diameter (1.74 +/- 0.60 vs. 1.56 +/- 0.65 mm, P = 0.007) and a lower rate of restenosis (31.6 percent vs. 42.1 percent, P = 0.046) than those treated with balloon angioplasty. There were no coronary events (death; myocardial infarction; coronary-artery bypass surgery; vessel closure, including stent thrombosis; or repeated angioplasty) in 80.5 percent of the patients in the stent group and 76.2 percent of those in the angioplasty group (P = 0.16). Revascularization of the original target lesion because of recurrent myocardial ischemia was performed less frequently in the stent group than in the angioplasty group (10.2 percent vs. 15.4 percent, P = 0.06). CONCLUSIONS: In selected patients, placement of an intracoronary stent, as compared with balloon angioplasty, results in an improved rate of procedural success, a lower rate of angiographically detected restenosis, a similar rate of clinical events after six months, and a less frequent need for revascularization of the original coronary lesion.

Angioplasty, Balloon, Coronary↗
PubMed1994

Is 40% to 70% diameter narrowing at the site of previous stenting or directional coronary atherectomy clinically significant?

Traditional binary definitions of coronary restenosis based on 6-month continuous angiographic measurements (e.g., > 50% diameter stenosis) may give confusing results for lesions whose late percent stenosis falls near the arbitrary threshold. To determine the long-term clinical consequences of such lesions, the overall correlation between follow-up percent stenosis and the performance of subsequent ischemia-driven target vessel revascularization (triggered by significant angina or a positive exercise study result, or both) was examined in 443 consecutive lesions treated with directional coronary atherectomy or Palmaz-Schatz coronary stenting. Follow-up angiograms (available in 355 lesions, 82%) were stratified into 3 groups: severe late stenosis (> 70% stenosis, n = 59), moderate late stenosis (40% to 70% stenosis, n = 72), and minimal late stenosis (< 40% stenosis, n = 224). With an average clinical follow-up of 933 +/- 394 days, 92% of lesions in the "severe late stenosis" group were treated with ischemia-driven target vessel revascularization, compared with 0% of the lesions in the "minimal late stenosis" group. Ischemia-driven target vessel revascularization was performed in 38% of patients in the "moderate late stenosis" group. However, patients in this group who did not undergo revascularization (despite the fact that 43% of them had a late stenosis of > 50%) showed a similarly favorable long-term clinical outcome to patients with a minimal late stenosis. These results support a strategy of conservative management for the 20% of patients who have a moderate (40% to 70%) late stenosis after stenting or atherectomy, but do not have evidence of ischemia.

Atherectomy, Coronary↗
PubMed1994

Effect of prior coronary restenosis on the risk of subsequent restenosis after stent placement or directional atherectomy.

Lesions that have developed restenosis after a prior intervention may be more likely to develop restenosis after subsequent percutaneous interventions. To determine if this is an independent effect, the clinical characteristics and immediate angiographic outcomes of 179 prior restenosis lesions were compared with those of 254 primary lesions after stenting or directional atherectomy. Six-month angiographic follow-up was obtained for 79% of successfully treated lesions. Univariable and multivariable logistic regression was used to determine how binary restenosis (defined as > or = 50% diameter stenosis at follow-up) was influenced by postprocedure luminal diameter, left anterior descending artery location, diabetes mellitus, as well as prior restenosis. At 6-month follow-up, prior restenosis lesions had a significantly smaller late diameter (1.77 vs 2.18 mm, p < 0.001), more absolute late loss (1.35 vs 1.14 mm, p = 0.051), a higher loss index (0.58 vs 0.45, p < 0.02), and a higher binary restenosis rate (37.3% vs 24.4%, p = 0.01). Whereas univariable analysis revealed that left anterior descending artery location, diabetes mellitus, postprocedure luminal diameter < 3.1 mm, and prior restenosis were each strong predictors of binary restenosis (all p < 0.02), multivariable analysis showed that after adjustment for left anterior descending artery location, diabetes, and postprocedure luminal diameter, prior restenosis was no longer an independent predictor of restenosis (odds ratio 1.57, 95% confidence interval 0.95-2.60, p = 0.073). In conclusion, although prior restenosis lesions do show more restenosis than primary lesions, much of this effect is due to preselection of a population enriched in other known factors that predispose to restenosis.

Angioplasty, Balloon, Coronary↗
PubMed1994

Inter-series differences in the restenosis rate of Palmaz-Schatz coronary stent placement: differences in demographics and post-procedure lumen diameter.

Restenosis rates following Palmaz-Schatz stenting vary between 13 and 36%. To determine whether the nearly three-fold interseries difference in restenosis rates reflects systematic factors (demographic and procedural variables such as post-treatment lumen diameter) rather than random variation, we pooled 486 lesions treated with the Palmaz-Schatz coronary stent in the U.S. Multicenter Registry (n = 259) with the single-center Beth Israel Hospital experience (n = 227) and analyzed the combined series using a continuous geometric model of restenosis. A greater proportion of lesions (66 vs. 50%; P < 0.001) in the Multicenter cohort represented restenosis after a prior intervention. The Multicenter experience also showed a smaller minimum lumen diameter following stent placement (2.61 vs. 3.43 mm; P < 0.001), higher post-stent percent stenosis (16 vs. -2%; P < 0.001), and less acute gain (1.79 vs. 2.67 mm; P < 0.001) than lesions treated in the Beth Israel cohort. At 6-month follow-up, the angiographic restenosis rate (> or = 50% diameter stenosis) was significantly higher in the Multicenter group (35 vs. 27%; P = 0.05), despite the development of less absolute late loss (0.96 vs. 1.32 mm; P < 0.001). Multivariable modeling, however, showed that the only independent predictors of restenosis were a post-procedure lumen diameter < 2.80 mm (odds ratio = 1.57; P = 0.04), diabetes mellitus (odds ratio = 3.55; P < 0.001), and prior restenosis (odds ratio = 1.84; P = 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)

Cohort Studies↗
PubMed1994

Myocardial perforation in the cardiac catheterization laboratory: incidence, presentation, diagnosis, and management.

The introduction of balloon valvuloplasty and new devices for coronary intervention has increased the incidence and changed the site and clinical presentation of cardiac perforation. We reviewed all cases of cardiac perforation that occurred during 11,845 consecutive catheterization procedures during a 6-yr period (1986-91). Fourteen cardiac perforations (overall incidence 0.12%) occurred as a result of the following procedures: mitral valvuloplasty 7 of 150 (4.7%), aortic valvuloplasty 4 of 260 (1.5%), pericardiocentesis 1 of 90 (1.1%), temporary pacer 1 of 1,660 (0.06%), and diagnostic left heart catheterization 1 of 6,965 (0.01%). Perforation was recognized in the catheterization laboratory in 11 patients, within 1 hr of leaving the laboratory in two patients, and 15 hr later in one patient. Hemodynamic evidence of tamponade developed in 13 patients and was confirmed by fluoroscopy (immobile heart borders) or echocardiography. Pericardiocentesis is definitive therapy in nearly half of the cases; the remaining patients require pericardiocentesis plus surgical repair of the perforation.

Aged↗
PubMed1994

Endoluminal stenting of a subclavian artery stenosis to treat ischemia in the distribution of a patent left internal mammary graft.

Subclavian artery stenosis is a rare cause of recurrent myocardial ischemia in patients who have undergone left internal mammary-coronary artery bypass grafting. A patient with this syndrome was successfully treated by placement of Palmaz biliary stents in the left subclavian artery. Angiographic and hemodynamic evidence of restricted subclavian flow resolved following stenting, as did the patient's unstable angina syndrome. Endoluminal stenting of the proximal subclavian artery for the treatment of coronary-subclavian steal can be performed safely and provides an alternative to other forms of surgical or percutaneous (PTCA, directional atherectomy) revascularization for treatment of this disorder.

Aged↗
PubMed1994

Complications and long-term outcome after percutaneous coronary angioplasty in chronic hemodialysis patients.

The objective of this investigation was to assess the acute and long-term outcome after coronary angioplasty in patients undergoing chronic hemodialysis. Previous studies have suggested a high incidence of restenosis after coronary angioplasty performed in patients with renal failure. Medical discharge abstracts for 8342 patients undergoing angioplasty during a 5-year period were searched to identify all coronary angioplasty procedures performed in patients undergoing chronic hemodialysis. Procedural and follow-up coronary angiograms were reviewed in a core angiographic laboratory. Hospital records and office visit notes were obtained to assess acute and long-term outcome. Twenty-one patients undergoing chronic hemodialysis had been treated by coronary angioplasty. The 9 men and 12 women had a mean age of 59 +/- 10 years (range 37 to 78 years) and had been undergoing hemodialysis for 6.2 +/- 6.4 years (range 1 to 19 years). Procedural success was achieved in 12 (57%) of 21 patients. Three (14%) patients died; 4 suffered nonfatal myocardial infarctions (19%); 1 (5%) required emergency bypass surgery; and 1 (5%) had abrupt vessel closure without complications. Of the 15 (71%) patients who were discharged with a patent angioplasty vessel, 4 (27%) died and 9 (60%) had recurrence of angina within 1 year. Of 9 patients with recurrent angina, 7 underwent a second angiography, and all showed evidence of restenosis at the previous angioplasty site. The results of coronary angioplasty in these 21 hemodialysis patients suggest a high rate of acute complications and poor long-term prognosis in this subgroup. Other strategies for revascularization should be considered for these patients.

Adult↗
PubMed1994

Palmaz-Schatz stenting for treatment of focal vein graft stenosis: immediate results and long-term outcome.

OBJECTIVES: This study aimed to evaluate the effectiveness of Palmaz-Schatz stenting for the treatment of saphenous vein graft stenoses. BACKGROUND: Failure of saphenous vein grafts is a common cause of recurrent ischemia after coronary bypass surgery. A second bypass surgery carries more risk than the initial procedure, and balloon angioplasty of vein grafts has yielded disappointing results. It has been hoped that stenting might offer a better treatment option. METHODS: We examined the results of stent placement in 200 saphenous bypass graft lesions consecutively treated with either coronary (n = 146) or biliary (n = 54) Palmaz-Schatz stents. Immediate outcome and clinical follow-up (median 15.5 months) were examined in all patients. To document angiographic outcome, a second angiography was performed at 3 to 6 months for the first 120 consecutively stented lesions and was successfully obtained for 94 (78%). RESULTS: The mean graft age (+/- SD) was 8.7 +/- 4 years. Stent placement was successful in 197 (98.5%) of 200 lesions, reducing the mean diameter stenosis from 74 +/- 14% to 1 +/- 15%. In 164 procedures, there was one in-hospital death (0.6%), no emergency bypass operations and no Q wave myocardial infarctions. There was one acute stent thrombosis (0.6%) but no subacute thromboses. Vascular repair was required after 14 procedures (8.5%), with transfusion in 23 additional cases (14%). Angiographic restenosis (diameter stenosis > or = 50%) at 3- to 6-month follow-up was 17% (95% confidence interval 9% to 25%). By Kaplan-Meier estimates, however, the 2-year second revascularization rate was 49%, reflecting the predominant revascularization performed to treat progressive disease at other sites because failure at the stented site occurred in only 22% of lesions. CONCLUSIONS: Stenting resulted in excellent immediate and long-term angiographic results in this group of focally diseased, older saphenous vein grafts. Despite the high immediate success and very low (17%) angiographic restenosis rate at 6 months, approximately one half of these patients required further revascularization in the following 2 years, mainly because of disease progression at other sites.

Aged↗
PubMed1994

Analysis of late lumen narrowing after excimer laser-facilitated coronary angioplasty.

OBJECTIVES: The purpose of this study was to analyze the quantitative angiographic factors affecting restenosis after excimer laser-facilitated coronary angioplasty. BACKGROUND: Restenosis after balloon angioplasty, directional atherectomy and coronary stenting has been analyzed using both dichotomous (> or = 50% diameter stenosis) and continuous (late lumen narrowing) end points, leading to the conclusion that achieving a large lumen diameter at the time of the procedure is associated with a lower risk of angiographic restenosis. METHODS: Quantitative angiographic measurements were made before treatment, after laser angioplasty, after adjunctive balloon angioplasty and at 6-month angiographic follow-up in 168 patients with 179 treated lesions. RESULTS: The immediate increase in lumen diameter (total acute gain 1.45 +/- 0.71 mm [mean +/- SD]) was due to the combination of laser treatment (0.79 +/- 0.61 mm) and subsequent adjunctive balloon angioplasty (0.66 +/- 0.55 mm). At follow-up, the minimal lumen diameter had decreased (late loss 0.71 +/- 0.84 mm), yielding an overall restenosis rate of 50% (defined dichotomously by > or = 50% diameter stenosis). Multivariable regression analyses showed that restenosis was related to vessel diameter, as well as minimal lumen diameter, achieved immediately after the procedure. CONCLUSIONS: Although the restenosis rates for the small vessels typically treated with excimer laser angioplasty were high, the lowest restenosis rates were seen in large vessels with the largest postprocedural minimal lumen diameters. The goal of this procedure should be to safely achieve the largest lumen possible with the combination of laser treatment and adjunctive balloon dilation.

Aged↗
PubMed1994

Cardiogenic shock induced by cocaine in swine with normal coronary arteries.

OBJECTIVE: The aim was to test the hypothesis that acute intravenous cocaine administration can cause coronary microvascular constriction culminating in myocardial ischaemia and cardiogenic shock. METHODS: Systemic haemodynamic variables and coronary blood flow were measured in 14 Yorkshire swine at baseline and following intravenous administration of 1, 3, and 10 mg.kg-1 of cocaine. Epicardial coronary artery diameter was measured from coronary arteriograms and coronary flow velocity was recorded with a Doppler flow wire. RESULTS: Cocaine produced a decrease in mean arterial pressure (65%), cardiac output (80%), and stroke volume (80%), and an increase in pulmonary artery diastolic pressure (60%). Although coronary blood flow decreased by 70%, epicardial coronary cross sectional area decreased by only 37-45%. Pretreatment with prazosin did not abolish the decrease in coronary blood flow. After administration of 10 mg.kg-1 of cocaine, five of 14 animals developed myocardial ischaemia and cardiogenic shock, culminating in ventricular fibrillation and death. CONCLUSIONS: In anaesthetised Yorkshire swine, cumulative intravenous doses of cocaine caused a significant reduction in coronary blood flow resulting in myocardial ischaemia, which cannot be attributed to epicardial vasoconstriction alone. This suggest that cocaine-induced coronary ischaemia may result from microvascular constriction, which is only partially prevented by alpha 1 blockade. In addition, direct toxic effects of cocaine on the myocardium may also contribute to the development of cardiogenic shock.

Animals↗
PubMed1994

Evaluating new devices. Acute (in-hospital) results from the New Approaches to Coronary Intervention Registry.

BACKGROUND: To be used optimally, new interventional devices (stent, lasers, atherectomy catheters) must be carefully evaluated in terms of optimal patient and lesion selection, technique of use, expected acute success and complications, and long-term results. Sources for that information include single-center and multicenter (single-device) reports, although randomized trials may then be performed to provide a more definitive picture of any clinical benefits. One interim option, however, consists of carefully collected registry data. The purpose of this article is to review data collected in the National Heart, Lung, and Blood Institute-funded New Approaches to Coronary Intervention (NACI) Registry and to compare them with existing reports. METHODS AND RESULTS: NACI is an independent, investigator-driven effort that seeks to collect uniform data on patients undergoing treatment with one of several investigational devices and thereby provide an unbiased report of procedure outcome. Between November 1990 and November 1992, 36 participating centers treated a total of 3201 lesions in 2835 patients, using one of seven study devices: directional atherectomy (1084 lesions), transluminal extraction atherectomy (240 lesions), rotational atherectomy (349 lesions), Palmaz-Schatz stent (674 lesions), Gianturco-Roubin stent (213 lesions), and the Advanced Interventional Systems (474 lesions) or Spectranetics (167 lesions) excimer lasers. Data on each procedure were recorded on a unique modular database that captured the reason for (and interim result after) each device use. Device success (defined here as stenosis improvement by > or = 20% and a residual stenosis < 50% after new device use) was 66.5% overall. Adjunctive angioplasty was used in 75.5% of lesions, either before (25.9%) or after (43.5%) new device use, yielding an overall lesion success (> or = 20% stenosis improvement with a final residual stenosis < 50% after all devices) of 92.2%. Adjunctive angioplasty after new device use produced further enlargement in minimal lumen diameter (from 2.2 to 2.7 mm) and further reduction in residual stenosis (26.4% to 16.1%) compared with the results present after use of the new devices themselves. Major complications consisting of death (1.6%), Q-wave myocardial infarction (1.3%), or emergency bypass surgery (1.7%) occurred in 4.0% of patients (range, 2.6% to 8.7% across devices). Procedural success, defined as lesion success in all new device-treated lesions without a major complication, was achieved in 90.8% of patients, with a median length of hospital stay of 4 days. CONCLUSIONS: NACI illustrates the type of information that can be obtained in a registry format that examines the acute angiographic and clinical results of new devices according to uniform definitions. Although no registry can substitute for formal interdevice trials, registries such as this can supplement earlier single-center and multicenter reports. In doing so, they can help focus subsequent randomized interdevice comparisons on lesion types for which two or more devices have promising acute results. Given the substantial interdevice differences in baseline patient and lesion characteristics found in NACI, simple "head-to-head" comparison of the results of different devices might give misleading impressions and should be avoided unless such comparisons are restricted to carefully matched patient and lesion subgroups.

Angioplasty, Laser↗
PubMed1994

Evaluating the potential cost-effectiveness of stenting as a treatment for symptomatic single-vessel coronary disease. Use of a decision-analytic model.

BACKGROUND: Coronary stenting appears to provide more predictable immediate results and lower rates of restenosis than conventional balloon angioplasty for selected lesion types, but its hospital costs are significantly higher. This study was designed to evaluate the potential cost-effectiveness of Palmaz-Schatz coronary stenting relative to conventional balloon angioplasty for the treatment of patients with symptomatic, single-vessel coronary disease. METHODS AND RESULTS: We developed a decision-analytic model to predict quality-adjusted life expectancy and lifetime treatment costs for patients with symptomatic, single-vessel coronary disease treated by either Palmaz-Schatz stenting (PSS) or conventional angioplasty (PTCA). Estimates of the probabilities of overall procedural success (PTCA, 97%; PSS, 98%), abrupt closure requiring emergency bypass surgery (PTCA, 1.0%; PSS, 0.6%), and angiographic restenosis (PTCA, 37%; PSS, 20%) were derived from review of the literature published as of September 1993. Procedural costs were based on the true economic (ie, variable) costs of each procedure at Boston's Beth Israel Hospital. On the basis of these data, coronary stenting was estimated to result in a higher quality-adjusted life expectancy than conventional angioplasty but to incur additional costs as well. Compared with conventional angioplasty, stenting had an estimated incremental cost-effectiveness ratio of $23,600 per quality-adjusted life year gained. Although the cost-effectiveness ratio for stenting changed with variations in assumptions about the relative costs and restenosis rates, it remained less than $40,000 per quality-adjusted year of life gained--and thus was similar to many other accepted medical treatments--unless the stent angiographic restenosis rate was > 23%, the angioplasty restenosis rate was < 34%, or the cost of stenting (including vascular complications) exceeded that of conventional angioplasty by more than $3000. The alternative strategy of secondary stenting (initial angioplasty followed by stenting only for symptomatic restenosis) was estimated to be both less effective and less cost-effective than primary stenting over a wide range of plausible assumptions and thus does not appear to be cost-effective when primary stenting is also an option. CONCLUSIONS: Decision-analytic modeling can be used to evaluate the potential cost-effectiveness of new coronary interventions. Our analysis suggests that despite its higher cost, elective coronary stenting may be a reasonably cost-effective treatment for selected patients with single-vessel coronary disease. Primary stenting is unlikely to be cost-effective for lesions with a low probability of restenosis (eg, < 30%) or for patients for whom the cost of stenting is expected to be much higher than usual (eg, because of a high risk of vascular complications). Given the sensitivity of the cost-effectiveness ratios to even modest variations in the relative restenosis rates and cost estimates, future studies will be necessary to determine more precisely the cost-effectiveness of coronary stenting for specific patient and lesion subsets.

Angioplasty, Balloon, Coronary↗
PubMed1994

Incidence and treatment of 'no-reflow' after percutaneous coronary intervention.

BACKGROUND: Profound reduction in antegrade epicardial coronary flow with concomitant ischemia is seen occasionally during percutaneous coronary intervention despite the absence of evident vessel dissection, obstruction, or distal vessel embolic cutoff. In a prior small series of cases, this "no-reflow" phenomenon appeared to be promptly reversed by the intra-coronary administration of verapamil. METHODS AND RESULTS: To further understand the prevalence of this syndrome and its responsiveness to the proposed therapy, we reviewed 1919 percutaneous interventions performed between January 1991 and April 1993. During the study period, 39 patients (2.0%) met our criteria for no reflow, 37 of whom were treated with intracoronary nitroglycerin followed by intracoronary verapamil and 2 of whom received intracoronary nitroglycerin alone. An additional 16 patients (0.8%) were given verapamil as part of the management of a flow-limiting dissection or distal embolus (mechanical obstruction). Intracoronary verapamil (50 to 900 micrograms, total dose) improved TIMI flow grade in 89% of no-reflow patients and markedly reduced the number of cineframes between contrast injection and opacification of a selected distal landmark (from 91 +/- 56 to 38 +/- 21 frames, P < .001). By contrast, only 19% of patients with epicardial mechanical obstruction showed improvement in TIMI flow grade after verapamil, with minimal reduction in frames to opacification (from 107 +/- 42 to 101 +/- 69, P = .73). CONCLUSIONS: The no-reflow phenomenon--reduction in distal flow without apparent dissection or distal embolization--occurs in 2% of coronary interventions. It generally responds promptly to intracoronary verapamil administration, suggesting that distal microvascular spasm may be its etiology.

Angioplasty, Balloon, Coronary↗