Impact of abciximab and coronary stenting on outcomes and costs of percutaneous coronary interventions in a community hospital.

OBJECTIVE: To assess costs and outcomes of coronary stenting and balloon angioplasty with and without adjunctive treatment with abciximab for 3758 consecutive elective percutaneous coronary interventions at a single community center over the 2.5-year period between 1 January 1995 and 30 June 1997. RESULTS: Abciximab was more common among patients who had recently suffered myocardial infarction, patients with unstable angina, and patients with more complex coronary lesions. Use of abciximab in conjunction with balloon angioplasty or stenting and stenting alone was associated with significant reductions in incidence of major adverse cardiovascular events in hospital. Multivariate analysis indicated that use of abciximab and stenting were associated with significant independent effects on risk of an event. Hospital costs were increased for patients administered abciximab, treated with stenting, or both. Total costs and costs inclusive of those incurred in catheterization laboratory and pharmacy increased significantly with increasing complexity of lesions. Multivariate regression analysis (baseline cost US$5621) identified death (US$16098), emergency revascularization (US$13678), usage of multiple stents (US$1423 for each stent), and use of abciximab (US$1269) as independent predictors of a greater cost. One-year follow-up revealed significant differences among treatment strategies in terms of risk of need for subsequent revascularization procedures. Lack of stenting but not use of abciximab was identified as a significant predictor of need for repeat revascularization procedures. CONCLUSIONS: Our findings are in general agreement with cost analyses of use of abciximab for populations in clinical trials and suggest that improvements of early clinical outcome with abciximab treatment and stenting justify the incremental cost of treatment in a community hospital setting.

Ad hoc coronary intervention.

Ad hoc coronary intervention is a percutaneous revascularization procedure performed at the same sitting as diagnostic cardiac catheterization. While this appears to be an efficient strategy, the safety and cost of ad hoc coronary intervention compared with delayed coronary intervention have not been clearly documented. Special preparation and precautions are necessary for patients in whom ad hoc coronary intervention is anticipated. Ad hoc coronary intervention is not appropriate if informed consent has not been previously obtained or if it would pose greater risks than delayed intervention. While ad hoc coronary intervention is often efficient and effective, its use should be individualized. Cathet. Cardiovasc. Intervent. 49:130-134, 2000.

Clopidogrel as adjunctive antiplatelet therapy during coronary stenting.

OBJECTIVES: We examined the procedural and 30-day clinical outcomes among patients receiving aspirin and either ticlopidine or clopidogrel during coronary stenting. BACKGROUND: Ticlopidine-plus-aspirin has become standard antiplatelet therapy for the prevention of thrombotic complications after coronary stenting. Clopidogrel has a similar mechanism of action as ticlopidine, but both its efficacy and its safety as a pharmacologic adjunct to coronary stenting have not been well described. METHODS: This single-center, prospective analysis examined the in-hospital procedural and 30-day clinical outcomes among 875 consecutive patients undergoing coronary stenting who received adjunctive aspirin and either clopidogrel (n = 514; 58.7%) or ticlopidine (n = 361; 41.3%) therapy. RESULTS: Procedural success rates were similar among the clopidogrel- (99.6%) and ticlopidine-treated patients (99.4%). Subacute stent thrombosis (i.e., >24 h < or =30 days) occurred in one clopidogrel-treated (0.2%) and in one ticlopidine-treated (0.3%) patient (p = 0.99). By 30 days following the index procedure, the combined rates of death, nonfatal myocardial infarction and need for target vessel revascularization were similar among patients who received either clopidogrel (2.1%) or ticlopidine (1.4%; p = 0.57) therapy. CONCLUSIONS: In this analysis the antiplatelet combination therapy of aspirin-plus-clopidogrel was an effective regimen for preventing thrombotic complications and major adverse cardiovascular events among a broad spectrum of patients undergoing coronary artery stenting.

Clinical predictors of improved long-term blood pressure control after successful stenting of hypertensive patients with obstructive renal artery atherosclerosis.

Despite a high procedural success rate, long-term blood pressure control after successful renal artery stenting of hypertensive patients has been inconsistent. This most likely reflects the absence of clinical guidelines for the selection of patients likely to benefit from renal revascularization. A cohort of 150 consecutive hypertensive patients (mean age, 66.7 years; 86 women) with 180 renal artery lesions (> or =75%) underwent primary Palmaz stent deployment. Mean arterial blood pressure (MAP), serum creatinine, and antihypertensive medication requirements were monitored prospectively. Specific definitions of blood pressure cure, improvement, or treatment failure were followed. Renal artery duplex Doppler or angiography was performed to assess stent patency at a mean 13 months (range, 7-15 months). Multivariate logistic regression analysis was used to select clinical variables that best related to a beneficial blood pressure control at follow-up. The procedural success rate was 97.3% (146 patients) and major in-laboratory complications were infrequent (1.3%). Late MAP values in 127 patients (91%) fell from 110 +/- 13.7 to 97.6 +/- 10.6 mm Hg (P < 0.001); antihypertensive medication requirements decreased from 2.9 +/- 1.2 to 1.9 +/- 1.1 (P < 0.01). The 13-month stent restenosis rate defined by duplex Doppler or angiography was 12%. Multivariate logistic regression analysis identified a preprocedure MAP of >110 mm Hg (odds ratio, 2.9; P = 0.003) and bilateral renal stenoses (odds ratio, 4.6; P = 0.009) as predictors of a beneficial blood pressure response at follow-up. This study provides general preprocedure guidelines for the selection of hypertensive patients with atherosclerotic renal lesions likely to benefit from primary Palmaz stenting and confirms a high procedural success and low stent restenosis rate.

Outpatient coronary stenting: femoral approach with vascular sealing.

Miniaturized devices and pressures for increased patient convenience and lowered cost have shortened length of stay for coronary interventions. A cohort of 60 patients was recruited to assess the feasibility of outpatient stenting with vascular sealing. Patients with stable and unstable angina or myocardial infarction > 24 hours were considered for this strategy. Mean time to hemostasis, ambulation and discharge were 6.1, 256 and 296 minutes, respectively, for the 6F group, and 11.0, 351 and 489 minutes for the 7 to 8F group. No acute procedural complications occurred, and there were no ischemic complications at 24 hours or 1 month. There was 1 pseudoaneurysm requiring surgical correction, but no other access site requiring treatment. The cost saved using the 6F approach is estimated at $478 and using the 8F approach, $437. Outpatient stenting using vascular sealing is feasible and safe, and may lead to significant nationwide cost reductions in the range of $40,000,000 yearly.

Economic implications of coronary stenting with adjunctive IIb/IIIa receptor antagonists in a community hospital.

To assess the implications of coronary stenting with several IIb/IIIa receptor antagonists, total hospital cost and adverse events were reviewed for 674 elective stent procedures from June 1998 through December 1998. The use of IIb/IIIa receptor antagonism and the agent selected were at the discretion of the interventional cardiologist. In-hospital, 30-day and 6-month adverse cardiac events were similar among the treatment strategies. Target vessel revascularization at six months was similar among the treatment strategies. Patients who received a IIb/IIIa receptor blocker with their stent procedure were less likely to be rehospitalized within 30 days. Multivariate regression analysis identified specific factors responsible for prolongation of hospital stay including adverse cardiac events, physician practice pattern and age greater than 70 years (all p < 0.002). Overall hospital cost for patients receiving tirofiban as an adjunct to coronary stenting was approximately $1,000 less than patients receiving abciximab. Total cath lab expenditures were similar for these groups and the savings in hospital cost was directly attributable to a lower pharmacy cost in the tirofiban group. Multivariate regression analysis identified adverse cardiac events, left ventricular systolic dysfunction, multiple stent placement, physician practice and abciximab as significant contributors to increased hospital cost (all p < 0.002). Tirofiban as an adjunct to coronary stenting was not identified by multivariate analysis as a significant contributor to hospital cost. Bleeding rates were similar among the treatment strategies. Thus, coronary stenting in our community hospital is associated with acceptable outcomes regardless of treatment strategy and hospital cost is significantly influenced by the use of IIb/IIIa blockade with stenting and the type of agent selected.

Outpatient coronary stenting using the femoral approach with vascular sealing.

PURPOSE: We report here the use of vascular sealing devices in conjunction with the use of small transfemoral guiding catheters to decrease time to ambulation, decrease cost associated with hospitalization and achieve early discharge. METHODS: Fifty patients were enrolled in this pilot project from two busy interventional practices between May 1997 and February 1999. Patients with stable or unstable angina or positive ETT and with recent myocardial infarction greater than 24 hours from the time of the procedure were included. Excluded patients included those who had received glycoprotein IIb/IIIa platelet inhibitors and those with intra-procedure access site complications. RESULTS: Of the 50 patients originally recruited, 49 underwent vascular sealing for hemostasis and 45 were discharged on the same day, as planned. Early home telephone follow-up was available on 41 of the 45 same-day discharge patients, of whom 30 noted no complaints. One patient, who had been re-accessed in the right femoral artery after a previous intervention, developed a pseudoaneurysm requiring surgical repair. One-month follow-up was available on all patients. No patient suffered a late ischemic event or access site complication requiring treatment. There were no instances of stent loss, acute closure or subacute thrombosis. CONCLUSION: Though limited by small numbers, this pilot study shows that selected patients undergoing coronary stenting via the femoral approach can be safely treated on an outpatient basis using vascular sealing devices. Cost savings may be significant using this strategy.

Nephrotoxicity from contrast media: attenuation with theophylline.

PURPOSE: To determine if depression of creatinine clearance after administration of contrast medium may be prevented with theophylline. MATERIALS AND METHODS: A nonionic, low-osmolality contrast medium (iopamidol) or an ionic, high-osmolality contrast medium (sodium diatrizoate) was administered to 93 patients. Before the examination, these patients were given theophylline or a placebo orally. There were also 30 patients who received an adenosine-uptake inhibitor (dipyridamole). Creatinine clearance and urinary adenosine levels were measured before and after angiography. RESULTS: Creatinine clearance decreased 18% +/- 4 in the placebo-iopamidol group but did not decrease in the theophylline group; urinary adenosine increased 67% +/- 7. Creatinine clearance decreased 42% +/- 5 in the placebo-sodium diatrizoate group and decreased 24% +/- 3 in the theophylline group; urinary adenosine increased 119% +/- 8. In the dipyridamole group in which iopamidol was given, urinary adenosine increased 96% +/- 7 and creatinine clearance decreased 37% +/- 5. CONCLUSION: Intrarenal adenosine can be implicated in the pathogenesis of hypertonic contrast medium nephrotoxicity.

Combined PTCA and microcoil embolization of a left internal mammary artery graft.

Internal mammary arteries are increasingly common conduits for coronary revascularization. Although infrequent, cardiologists are faced with a number of technical failures. We describe a case of combined PTCA to a LIMA insertion stenosis, along with coil embolization of a large unligated intercostal side branch. A complication of embolization is described along with angiographic follow-up.

Production and reversibility of right ventricular hypertrophy and right heart failure in dogs.

Combined heart-lung transplantation has been used for end-stage primary pulmonary hypertension. Experience with single-lung transplantation for other conditions suggested that associated severe right ventricular dysfunction resulting from increased afterload would recover after placement of a satisfactory lung allograft. Early experience with the application of single-lung transplantation for pulmonary hypertension supports this contention. We devised a reversible canine model of chronic progressive pressure-overloaded right heart failure by pulmonary artery banding to study the echocardiographic, hemodynamic, and pathological reversibility of the failing right heart. Clinical right heart failure was defined as the development of ascites and pleural effusions. Right heart failure developed in 23 dogs 67 to 348 days after banding, and they were divided into two groups to determine its early and long-term effects. Group 1 dogs (n = 11) were either sacrificed immediately after the onset of right heart failure (n = 5) or unbanded (n = 6); group 2 dogs (n = 12) were maintained in right heart failure for 3 months and then either sacrificed (n = 6) or unbanded. Unbanded dogs in both groups were observed for 4 additional months before sacrifice. A control group of 6 normal dogs was sacrificed for pathological comparisons. After unbanding, the right ventricular systolic pressure fell from 97 +/- 17 mm Hg (group 1) and 88 +/- 31 mm Hg (group 2) to 44 +/- 11 mm Hg and 47 +/- 13 mm Hg, respectively. Despite this persistent gradient across the pulmonary artery, echocardiographic and hemodynamic measures of right ventricular function returned to normal, albeit more slowly in the group 2 dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Total occlusion of the circumflex artery with collateral supply from the conus artery.

The conus artery has long been recognized as an important source of collateral blood supply to a significantly diseased left anterior descending artery. This artery which arises 50% of the time from a separate orifice in the right sinus of Valsalva may also provide collateral circulation to a diseased right coronary artery. To date, there have been no reported instances of the conus artery supplying collateral flow to a totally occluded circumflex artery. In this report we describe such a case in a patient with severe three vessel disease. The implications of such a finding in patient management are also discussed.

Recovery of elevated atrial natriuretic peptide in pressure-overload right heart failure.

Elevation of the plasma concentrations of immunoreactive atrial natriuretic peptide (ANP) was observed in canine chronic right heart failure (RHF) secondary to right ventricular (RV) pressure overload. Pressure overload on the right heart was gradually increased using an inflatable cuff. The interval between banding and the onset of RHF was 152 +/- 52 days. Seventeen RHF dogs were produced and divided into Group I (n = 11) and Group II (n = 6). At the onset of RHF, Group I dogs were either sacrificed for study of the heart, or unbanded to allow recovery from RHF. The dogs in Group II were maintained in RHF for 3 additional months before being either sacrificed or unbanded. Following unbanding, the ANP level of Group I recovered from 108 +/- 36 (n = 11) to 20 +/- 6 pg/ml (n = 6) at 1 month and was maintained at 27 +/- 7 pg/ml (baseline, 21 +/- 5 pg/ml, n = 11) at 4 months. ANP levels of Group II declined from 165 +/- 55 (n = 6) to 87 +/- 2 pg/ml (n = 3) at 1 month and further decreased to 42 +/- 14 pg/ml (n = 3) 4 months after unbanding. Thus, compared to Group I, Group II had a high ANP level before unbanding and a delay in recovery of the ANP levels despite normalization of the right atrial pressure (RAP). Four months after release of pressure overload, the right atrial hypertrophy persisted in the unbanded dogs; however, Group I unbanded dogs showed a better reversal of the right atrial hypertrophy than Group II unbanded dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Restenosis and accelerated left main coronary artery disease presenting six months after successful percutaneous transluminal coronary angioplasty.

Percutaneous transluminal coronary angioplasty (PTCA) is widely used to achieve myocardial revascularization because of its high success rate and low rate of complications. A 30% rate of restenosis remains the most serious hurdle to overcome. This phenomenon results from endothelial injury caused by balloon inflation. However, not widely appreciated is that other components of PTCA equipment can cause endothelial injury and lead to new stenoses proximal to the dilated lesion. This phenomenon has serious implications when it involves the left main artery. Described here is a case of restenosis involving the left anterior descending artery as well as accelerated left main disease.

A simplified concept for a bileaflet atrioventricular valve that maintains annular-papillary muscle continuity.

We have developed a simplified concept for a bileaflet atrioventricular prosthesis that can be constructed from a simple sheet of glutaraldehyde preserved pericardium. The valve has no rigid ring or stent and no cloth sewing ring. Insertion of the valve reestablishes normal continuity between the annulus and the papillary muscles. We have replaced the mitral valve in nine dogs using this prosthesis. All valves have been competent with excellent valve opening areas as confirmed by echo-Doppler assessment. Studies up to 4 1/2 months have confirmed excellent hemodynamics and there has been no evidence of early tissue failure. Possible advantages of this simple valve design are improved hemodynamics, ease of construction and insertion, and low cost.

Comparison of high-dose with low-dose subcutaneous heparin to prevent left ventricular mural thrombosis in patients with acute transmural anterior myocardial infarction.

We performed a double-blind randomized trial comparing high doses of subcutaneous heparin (12,500 units every 12 hours) with low doses (5000 units every 12 hours) for 10 days in the prevention of left ventricular mural thrombosis in 221 patients with acute anterior myocardial infarction. Left ventricular mural thrombosis was observed by two-dimensional echocardiography on the 10th day after infarction in 10 of 95 patients (11 percent) in the high-dose group and in 28 of 88 patients (32 percent) in the low-dose group (P = 0.0004). One patient in the high-dose group and four in the low-dose group had nonhemorrhagic strokes (P = 0.17). One patient in the low-dose group had a fatal pulmonary embolism. There was no difference in the frequency of hemorrhagic complications, which occurred in six patients in the high-dose group and four in the low-dose group. The mean (+/- SEM) plasma heparin concentration was 0.18 +/- 0.017 U per milliliter in the high-dose group and 0.01 +/- 0.005 U per milliliter in the low-dose group (P less than 0.0001). In the high-dose group, the mean plasma heparin concentration was 0.10 +/- 0.029 U per milliliter among patients with abnormal two-dimensional echocardiograms, as compared with 0.19 +/- 0.019 U per milliliter among patients with normal echocardiograms (P = 0.01). We conclude that heparin administered subcutaneously in a dosage of 12,500 units every 12 hours to patients with acute anterior transmural myocardial infarction is more effective than a lower dosage (5000 units every 12 hours) in preventing left ventricular mural thrombosis.