Oscar Rosales

Intracoronary adenosine administered during percutaneous intervention in acute myocardial infarction and reduction in the incidence of 'no reflow' phenomenon

Percutaneous intervention in acute myocardial infarction has been associated with a high incidence of “no reflow,” ranging from 11% to 30%, with an increased risk of complications. The role of intracoronary adenosine for the prevention of this phenomenon has not been evaluated fully. We studied the procedural outcomes of 79 patients who underwent percutaneous intervention in the context of acute myocardial infarction. Twenty‐eight patients received no intracoronary adenosine, and 51 received intracoronary adenosine boluses (24–48 μg before and after each balloon inflation). Eight patients who were not given adenosine experienced no reflow (28.6%) and higher rates of in‐hospital death, while only three of 51 patients (5.9%; P =0.014) in the adenosine group experienced no reflow. No untoward complications were noted during adenosine infusion. Intracoronary adenosine bolus administration during percutaneous intervention in the context of acute myocardial infarction is easy and safe and may significantly lessen the incidence of no reflow, which may improve the outcome of this procedure. Cathet. Cardiovasc. Intervent. 51:27–31, 2000.

Adenosine use during aortocoronary vein graft interventions reverses but does not prevent the slow-no reflow phenomenon.

Slow or no reflow (SNR) complicates 10–15% of cases of percutaneous intervention (PI) in saphenous vein bypass graft (SVG). To date there have been limited options for the prevention and treatment of this common and potentially serious complication. We evaluated the procedural outcome of 143 consecutive SVG interventions. We compared patients who received pre‐intervention intra‐graft adenosine boluses with those who did not. In addition we examined the efficacy of adenosine boluses to reverse slow‐no reflow events. Angiograms were reviewed and flow graded (TIMI grade) by film readers blinded to the use of any intraprocedural drug or clinical history. Seventy patients received intragraft adenosine boluses before percutaneous intervention (APPI), 73 received no preintervention adenosine (NoAPPI). There were no significant angiographic differences between the two groups at baseline. A total of 20 patients experienced SNR. The incidence of SNR was similar in the two groups (APPI = 14.2% vs. NoAPPI = 13.6%, P = 0.9). SNR was treated with repeated, rapid boluses (24 μg each) of intra‐graft adenosine. Reversal of SNR was observed in 10 of 11 patients (91%) who received high doses of adenosine (≥5 boluses, mean 7.7 ± 2.6) and in 3 of 9 (33%) of those who received low doses (<5 boluses, mean 1.5 ± 1.2). Final TIMI flow was significantly better in the high dose than in the low dose group (final TIMI 2.7 ± 0.6 vs. 2 ± 0.8, P = 0.04). No significant untoward complications were observed during adenosine infusion. These findings suggest that SNR after PI in SVG is not prevented by pre‐intervention adenosine, but it can be safely and effectively reversed by delivery of multiple, rapid and repeated boluses of 24 μg of intra‐graft adenosine. Cathet. Cardiovasc. Intervent. 51:394–399, 2000.

Outcome of access site in patients treated with platelet glycoprotein IIb/IIIa inhibitors in the era of closure devices

The most consistent procedural predictor of vascular access site complications thus far has been the intensity and duration of anticoagulant therapy during and after percutaneous coronary interventions (PCI). Several devices have been developed to aid in the closure of the femoral arteriotomy. This report describes the clinical outcome of unsuccessful deployment of femoral closure devices in a cohort of 285 consecutive patients who underwent PCI and were treated with platelet glycoprotein (GP) IIb/IIIa inhibitors. Manual femoral artery compression was used in 123 patients, Perclose in 123 patients, and AngioSeal in 39 patients. Successful homeostasis was achieved in 98.4% of patients who received manual compression, in 91.9% of the Perclose‐sealed arteriotomy, and in 84.6% of patients who received the AngioSeal closure device (P = 0.004). The incidence of vascular complications after successful deployment was 9%. Patients not achieving hemostasis with closure device or 1° manual compression developed complications in the majority of cases (> 80%; P < 0.05). By multivariate analysis (with adjustment for baseline differences), the use of AngioSeal closure device was found to be an independent risk factors leading to primary deployment failure and all access site complications (OR 2.97; 95% CI 1.5–6.0; P = 0.006). In summary, failed hemostasis by artery closure devices in patients undergoing PCI who are treated with GP IIb/IIIa inhibitors is associated with significant vascular complications. AngioSeal may be associated with a higher failure rate, while manual compression and Perclose seem to be more effective with a lower complication rate. Cathet Cardiovasc Intervent 2003;58:1–5.

Effects of clopidogrel pretreatment before percutaneous coronary intervention in patients treated with glycoprotein IIb/IIIa inhibitors (abciximab or tirofiban)

T clinical efficacy and safety of clopidogrel pretreatment in addition to glycoprotein (GP) IIb/IIIa antagonists during percutaneous coronary intervention (PCI) is unknown. This study compares the in-hospital clinical outcome of patients who received clopidogrel pretreatment before PCI with that in patients who did not receive it as adjunctive antiplatelet therapy to GP IIb/IIIa antagonists. • • • Data were collected from the Memorial Hermann Heart Center Interventional Cardiology database. We examined a consecutive series of 299 patients undergoing PCI. All patients received GP IIb/IIIa inhibitor therapy in the form of abciximab or tirofiban. Use and type of GP IIb/IIIb antagonists was at the discretion of the operator. Abciximab was given as a bolus dose of 0.25 mg/kg body weight followed by continuous infusion of 10 g/min for 12 hours. Tirofiban was given as a loading dose of 0.4 g/kg/min for 30 minutes followed by a maintenance dose of 0.1 g/kg/min for 12 to 24 hours after the procedure. All patients were taking aspirin and received a heparin bolus to achieve an activated clotting time between 250 and 300 seconds. Patients presenting to the catheterization laboratory with a developing myocardial infarction (MI) for a primary or rescue angioplasty were excluded. Patients were divided into 2 groups: those who received clopidogrel pretreatment before PCI (starting within 5 days before PCI or a loading dose of 300 mg the morning of the day of the procedure at the discretion of the primary operator, group I), and those who received aspirin alone (group II) with clopidogrel (300 mg loading dose and 75 mg/day for 1 month) given after stent deployment. Therapy with clopidogrel (75 mg/day) was continued for 1 month in both groups if the stent was deployed during the procedure. Coronary angioplasty and intracoronary stent implantation were performed using standard percutaneous techniques. Balloon size was selected to match the reference vessel diameter obtained from on-line angiographic analysis (1.1:1 balloon/artery ratio). Different types of stents were used (excluding open coil type). After stent implantation, high-pressure balloon dilatation was performed for angiographic optimization. Intravascular ultrasonography–guided coronary stenting was not performed in most patients. Each operator relied on his own judgment or on other objective measurements, such as online quantitative coronary angiography, to assess PCI results. On completion of the procedure, patients were moved to a monitored unit and the arterial sheath was removed. Successful PCI was defined as final residual stenosis within the treated lesion of 20%, with achievement of Thrombolysis In Myocardial Infarction grade 3 flow, without in-lab occurrence of death, MI, or a complication requiring immediate coronary revascularization. A major adverse cardiac event was defined as any 1 of the following: (1) Q-wave or non–Q-wave MI, (2) need for urgent repeat target vessel revascularization, or (3) cardiovascular death that occurred during the period of hospitalization after the index coronary procedure. Postprocedural MI was defined as the occurrence of typical ischemic chest pain of 30 minutes duration with a creatine kinase elevation of 3 times the upper limit of normal with an associated increase in the MB fraction. There was no routine protocol for acquisition of postprocedure creatine kinase. All postprocedural cardiac enzymes were obtained for suspected recurrent myocardial ischemia, manifested by recurrent postprocedural chest pain, hemodynamic instability, or new electrocardiographic changes of ischemia. Urgent target vessel revascularization was defined as a repeat PCI or coronary artery bypass grafting of the index artery due to presumed recurrent ischemia manifested by recurrent angina, arrhythmias, or hemodynamic compromise. Adverse effects of therapy were recorded and compared between the 2 groups. These consist of major bleeding and thrombocytopenia. Major bleeding was defined as bleeding requiring transfusion of blood products or precipitating hemodynamic compromise. Intracerebral hemorrhage of any extent was considered a major adverse effect of therapy. Thrombocytopenia was defined as platelet count 100,000/mm. Chi-square and Fischer exact tests were used for analysis of categorical variables when appropriate, and Student t testing was used for analysis of continuous variables. Multivariate logistic regression analysis was performed to determine significance of variables related to an in-hospital major adverse cardiac From the Cardiology Division, University of Texas Medical School and Hermann Heart Center, Memorial Hermann Hospital, Houston, Texas. Dr. Rosales’ address is: Division of Cardiology, University of Texas Health Science Center-Houston, PO Box 20708, Houston, Texas 77225-0708. Manuscript received March 29, 2001; revised manuscript received and accepted May 30, 2001.

Estrogen replacement therapy and outcome of coronary balloon angioplasty in postmenopausal women

Estrogen replacement therapy (ERT) in women after menopause is associated with prevention of clinical coronary artery disease. However, few studies have investigated possible benefits from ERT in postmenopausal women undergoing treatment for established coronary disease. We therefore retrospectively reviewed the clinical outcomes of 428 postmenopausal women undergoing percutaneous transluminal coronary balloon angioplasty (PTCA) to test the hypothesis that ERT has a beneficial effect in this setting. The women were divided into 2 groups based on ERT status at the time of the procedure. Estrogen users were younger (60 +/- 10 vs 68 +/- 9 years, p <0.001), more commonly had family histories of coronary heart disease (54% vs 41%, p = 0.04), had less incidence of hypertension (63% vs 76%, p = 0.02), and had slightly fewer diseased vessels per patient (1.3 +/- 0.5 vs 1.5 +/- 0.7, p = 0.03) compared with nonusers. No in-hospital deaths occurred in estrogen users compared with 5% hospital mortality in nonusers (p = 0.01). The combined outcome of death or myocardial infarction (MI) also was lower in estrogen users (4% vs 12%, p = 0.04). Of 348 women discharged after successful PTCA, 336 (97%) were able to be contacted at an average follow-up interval of 22 +/- 17 months (range 5 to 82). Estrogen users had superior event-free survival both for death as well as for death or nonfatal MI. Repeat revascularizations were similar in both groups (32% vs 24%, p = 0.15). In a Cox proportional-hazards model, nonusers had 4 times the likelihood of death after angioplasty compared with estrogen users (OR = 4.025, 95% CI = 1.3 to 13.4, p = 0.02). We conclude that estrogen replacement may offer protection against clinical coronary events in postmenopausal women who already have established coronary disease and are undergoing balloon angioplasty. The benefit was independent of age, smoking, presence of diabetes mellitus, or the number of diseased coronary vessels. However, it did not include a reduction in repeat revascularization procedures, suggesting no reduction in restenosis.

Combined cutting balloon angioplasty and intracoronary beta radiation for treatment of in‐stent restenosis: Clinical outcomes and effect of pullback radiation for long lesions

Intracoronary beta (β) radiation decreases the incidence of target lesion revascularization after percutaneous intervention (PCI) for in‐stent restenosis (ISR). Cutting balloon (CB) angioplasty may also be superior to other percutaneous techniques for the treatment of ISR. We sought to study the outcomes of patients with ISR who underwent both CB angioplasty and intracoronay β radiation and compare them to patients with ISR who underwent other PCI techniques without concomitant radiation. We also sought to evaluate the safety and efficacy of pullback intracoronary β radiation for the treatment of long ISR lesions. Between January 2001 and November 2001, 102 patients (mean age = 55 ± 13 years) with ISR underwent both CB angioplasty and intracoronay β radiation. β radiation was delivered using the Beta Cath (Novoste) 30 mm system, and pullback radiation was performed in 41 patients. A comparison group included a total of 393 patients with ISR who underwent other PCI techniques without concomitant intracoronary radiation therapy. Follow‐up was obtained in 99 patients (97%) in the CB angioplasty with intracoronary radiation group and 377 patients (96%) in the comparison group. At follow‐up, both target vessel revascularization (TVR) and major adverse cardiovascular events (MACE) occurred significantly less in the CB angioplasty with intracoronary radiation group than in the comparison group (7% vs. 18% for TVR, and 14% vs. 24% for MACE; P < 0.05 for both). In the pullback radiation group, TVR was performed in five patients (12%), and MACE occurred in eight patients (20%). A combination of CB angioplasty and intracoronay β radiation for ISR seems to yield low rates of subsequent target vessel revascularization and adverse cardiac events. In addition, pullback β radiation using the Beta Cath (Novoste) 30 mm system is safe and can be used to treat long ISR lesions effectively. Further randomized trials are needed to confirm these findings. Cathet Cardiovasc Intervent 2002;57:325–329.

Causes of early reintervention after successful coronary artery stenting.

Acute reintervention was performed in 26 of 1,620 patients after coronary stenting (1.6%). Half of the patients had stent thrombosis and the other half residual anatomic problems. The mean time for reintervention was shorter in patients with stent thrombosis. All patients with stent thrombosis had a sudden recurrence of chest pain. Electrocardiographic changes were more common with stent thrombosis. Composite end point occurred in 10 patients (77%) with stent thrombosis versus 5 (39%) in the other group (p = 0.04).

Abciximab administration and clinical outcomes after percutaneous intervention for in-stent restenosis

Abciximab therapy improves clinical outcomes after percutaneous interventions for de novo coronary artery disease. We sought to determine whether clinical outcomes after percutaneous intervention for in‐stent restenosis are affected by abciximab administration. Between January 1996 and July 1999, 322 consecutive patients underwent percutaneous intervention for in‐stent restenosis; 157 patients received abciximab and 165 patients were treated without abciximab based on operator discretion. Baseline clinical and angiographic variables and type of percutaneous intervention were recorded. Follow‐up information was obtained and clinical endpoints were recorded. A multivariate analysis was performed to determine the independent variables associated with adverse clinical outcomes. Baseline clinical and angiographic variables were similar in both groups. Patients who received abciximab were more likely to be treated with rotational atherectomy and less likely to have only balloon angioplasty or repeat stenting. Mean follow‐up duration was 19 ± 12 months. There were no significant differences in the incidence of angina/myocardial infarction (29% vs. 30%; P = 0.9), target vessel revascularization (18% vs. 21%; P = 0.5), death (8% vs. 7%; P = 0.4), or major adverse cardiovascular events (38% vs. 39%; P = 0.9) in both groups. Abciximab administration was not an independent variable associated with adverse outcomes. In this observational study, clinical outcomes after percutaneous intervention for in‐stent restenosis did not seem to be affected by abciximab administration. Randomized trials are needed to identify the role of platelet glycoprotein IIb/IIIa inhibitors in the management of in‐stent restenosis. Cathet Cardiovasc Intervent 2002;56:184–187.