The influence of age on the clinical results after rescue angioplasty (percutaneous coronary intervention [PCI]) has been poorly investigated. In the present study, we evaluated the outcome of 514 consecutive patients undergoing rescue PCI who were divided into 2 groups according to age: <75 years (n = 469) and ≥75 years (n = 45). The primary end point of the study was the incidence of death at 1 year of follow-up. The secondary end point was the 1-year incidence of major cardiac adverse events (MACE) defined as a composite of death, recurrent acute myocardial infarction, and target vessel revascularization. The predictors of death and MACE at 1 year were also investigated. At 1 year of follow-up, the <75-year-old group had a significantly lower incidence of death (7% vs 24%, p = 0.0001) and MACE (14% vs 28%, p = 0.01) compared to the ≥75-year-old group. The Cox proportional hazards model identified age (adjusted hazard ratio 0.2665, 95% confidence interval 0.1285 to 0.5524, p = 0.0004), cardiogenic shock (hazard ratio 0.1057, 95% confidence interval 0.0528 to 0.2117, p <0.000001), Thrombolysis In Myocardial Infarction flow grade 2 to 3 after PCI versus 0 to 1 (hazard ratio 3.8380, 95% confidence interval 1.7781 to 8.2843, p = 0.0006), multi- versus single-vessel disease (hazard ratio 0.3716, 95% confidence interval 0.1896 to 0.7284, p = 0.0039) as independent predictors of survival at 1 year of follow-up. In conclusion, at 1 year of follow-up after rescue PCI, the patients aged ≥75 years had a greater incidence of death and MACE compared to patients aged <75 years. Age, cardiogenic shock, Thrombolysis In Myocardial Infarction flow grade 0-1 after PCI, and multivessel coronary disease were predictors of survival and freedom from MACE at 1 year of follow-up.
The treatment of acute myocardial infarction (AMI) in older patients is an important challenge, because the elderly are at an increased risk of death and major adverse cardiac events (MACE). Despite its potential benefits, primary percutaneous coronary intervention angioplasty (PCI) is not always feasible, and fibrinolysis remains the most common initial therapy. Pharmacologic reperfusion can improve survival, but it is unable to restore normal Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow of the infarct-related artery in 40% to 50% of cases, mostly in the elderly. These patients have a greater mortality rate than those with successful reperfusion, but PCI is a useful rescue strategy. However, only limited data are available regarding the clinical outcome of older patients undergoing rescue PCI. The aim of the present study was to evaluate the clinical characteristics, angiographic patterns, procedural details, and 1-year clinical outcomes of patients ≥75 years old compared to patients <75 years old undergoing rescue PCI and to identify the predictors of 1-year adverse outcomes.
Methods
From July 1997 to October 2009, 514 consecutive patients with AMI underwent rescue PCI at our institution for failed fibrinolysis performed within the previous 12 hours. The patients were divided into 2 groups according to age (<75 years [average 56 ± 9, range 29 to 74] and ≥75 years [average 79 ± 4, range 75 to 90]), which included 469 and 45 patients, respectively. The diagnosis of AMI was established on the basis of typical chest pain lasting >30 minutes, unrelieved by sublingual nitrates, associated with ST-segment elevation (≥1 mV in ≥2 limb leads or ≥0.2 mV in ≥2 contiguous precordial leads) or left bundle branch block of new onset on a surface electrocardiogram. Failed thrombolysis was defined by a second 12-lead electrocardiogram obtained 60 minutes after the onset of fibrinolytic therapy, showing failure of the ST-segment elevation in the worst lead to have resolved by 50% compared to the baseline electrocardiogram, as well as the absence of chest pain relief. Patients undergoing “facilitated” rescue PCI without rescue criteria were not included. All patients had received intravenous aspirin 300 to 500 mg and unfractionated heparin 60 UI/kg body weight at the admitting hospital. At arrival at our department, the patients were pretreated with 500 mg ticlopidine (until July 2002) or 300 mg clopidogrel (from August 2002). Abciximab was administrated at the discretion of the operator: an intravenous preprocedural bolus of 0.25 mg/kg body weight followed by a continuous infusion of 0.125 μg kg −1 /min −1 for 12 hours (up to a maximum dose of 10 μg/min). During PCI, an intravenous bolus of unfractionated heparin was given to maintain an activated clotting time of ≥200 seconds. All patients were discharged with aspirin (100 mg) indefinitely and ticlopidine (500 mg) or clopidogrel (75 mg) daily for 6 to 12 months. The follow-up protocol included an evaluation at hospital discharge and a clinical visit thereafter at 1, 6, and 12 months. A stress test was scheduled at 6 to 11 months. Only patients with spontaneous or inducible ischemia underwent repeat coronary angiography.
The number of critically narrowed coronary arteries was evaluated. Angiographic analysis was performed on end-diastolic frames demonstrating the stenosis on its more severe view. The view with the least foreshortening was selected for the analysis. The initial and final flow in the infarct-related artery was graded according to the TIMI classification.
The primary end point of the study was the 1-year incidence of death. The secondary end point was the 1-year incidence of MACE, defined as a composite of death resulting from any cause, recurrent myocardial infarction, and target vessel revascularization. Recurrent myocardial infarction was diagnosed in the presence of new pathologic Q waves on the electrocardiogram or an increase in creatine kinase of more than twice the upper limit of normal. Target vessel revascularization consisted of repeat PCI or coronary artery bypass surgery for restenosis or reocclusion of the target vessel in the presence of objective evidence of ischemia. The in-hospital incidence of MACE, major bleeding, and vascular complications at 30 days were also recorded. Major bleeding was defined as an intracranial or a clinically significant (decrease in hemoglobin >5 g/dl). Vascular complications were defined as the need of surgical repair for hematoma (diameter >10 cm), pseudoaneurysm, or arteriovenous fistula at the access site.
A retrospective analysis of the data prospectively collected according to our internal protocol was performed. The data are presented as the mean ± SD or percentages. The comparisons between groups were performed using the t test for continuous data and the chi-square test or Fisher exact test for categorical data. The Cox proportional hazards model was used to determine the independent correlates of the composite primary end point at 1 year. Survival and freedom from MACE curves were developed using the Kaplan-Meier method. The analyses were performed using the Statistical Package for Social Sciences (Insightful, Seattle, Washington). Statistical significance was accepted at p <0.05.
Results
The baseline characteristics are listed in Table 1 . The angiographic and procedural variables are listed in Table 2 . Data regarding clinical follow-up were available for all patients at 30 days and for 479 patients (93%) at 1 year (34 and 3 patients were lost in the <75-year group and ≥75-year group, respectively, p = 0.88). The adverse events at 30 days and 1 year of follow-up are detailed in Table 3 . The adverse events at 30 days and 1 year of follow-up are detailed in Table 3 . During rescue PCI, 6 patients in the <75-year group and no patients in the ≥75-year group died (p = 0.44). A total of 4 major bleeding events (1 fatal intracranial bleeding event and 1 requiring transfusion in each group; p = 0.04) and 2 major vascular complications (1 pseudoaneurysm requiring surgery in each group; p = 0.16). The 1-year overall survival and free from MACE survival rate was 95.6% and 83.6% (p = 0.001) and 88.3% versus 76.7% (p = 0.001) in the <75-year and ≥75-year group, respectively. The adjusted Cox model estimates for cumulative survival and freedom from MACE rates are detailed in Figures 1 and 2 , respectively.
| Variable | Age <75 y (n = 469) | Age ≥75 y (n = 45) | p Value |
|---|---|---|---|
| Women | 58 (12%) | 13 (29%) | 0.002 |
| Previous myocardial infarction | 22 (5%) | 3 (7%) | 0.26 |
| Diabetes mellitus | 81 (17%) | 8 (18%) | 0.93 |
| Arterial hypertension ⁎ | 227 (48%) | 25 (55%) | 0.36 |
| Hypercholesterolemia † | 166 (35%) | 14 (31%) | 0.56 |
| Current smoker | 222 (47%) | 10 (22%) | 0.001 |
| Ejection fraction (%) | 47 ± 10 | 48 ± 11 | 0.54 |
| Myocardial infarct localization | 0.46 | ||
| Anterior | 283 (60%) | 25 (55%) | |
| Inferior | 139 (30%) | 17 (38%) | |
| Inferolateral | 47 (10%) | 3 (7%) | |
| Cardiogenic shock ‡ | 28 (6%) | 4 (9%) | 0.43 |
| Thrombolytic drug | 0.16 | ||
| Streptokinase | 5 (1%) | 2 (4%) | |
| Alteplase | 234 (50%) | 23 (51%) | |
| Reteplase | 230 (49%) | 20 (44%) | |
| Interval from pain to percutaneous coronary intervention (hours) | 8 ± 5 | 8 ± 5 | 0.77 |
| Interval from pain to thrombolysis (hours) | 4 ± 3 | 4 ± 3 | 0.73 |
⁎ Defined as systolic blood pressure >140 mm Hg, diastolic blood pressure >90 mm Hg, or use of blood pressure-lowering agents.
† Defined as total cholesterol >230 mg/dl or use of a lipid-lowering agent.
‡ Defined as blood pressure <90 mm Hg, heart rate >100 beats/min, and the patient cool, clammy, or requiring inotropes, intra-aortic balloon pump, or cardiopulmonary support to assist the circulation.
| Variable | Age <75 y (n = 469) | Age ≥75 y (n = 45) | p Value |
|---|---|---|---|
| Target coronary artery | 0.57 | ||
| Left main | 7 (1%) | 0 | |
| Left anterior descending | 276 (59%) | 25 (55%) | |
| Left circumflex | 46 (10%) | 3 (6%) | |
| Right | 140 (30%) | 17 (37%) | |
| Treated coronary segment | 0.64 | ||
| Ostial | 22 (5%) | 4 (9%) | |
| Proximal | 182 (39%) | 18 (40%) | |
| Middle | 207 (44%) | 18 (40%) | |
| Distal | 58 (12%) | 5 (11%) | |
| Number of narrowed coronary arteries | 0.13 | ||
| 1 | 317 (67%) | 26 (58%) | |
| 2 | 111 (24%) | 11 (24%) | |
| 3 | 41 (9%) | 8 (18%) | |
| Number of treated coronary arteries | 0.32 | ||
| 1 | 424 (90%) | 40 (89%) | |
| 2 | 43 (9%) | 4 (9%) | |
| 3 | 2 (0.4%) | 1 (2%) | |
| Thrombolysis In Myocardial Infarction flow grade before intervention | 0.39 | ||
| 0 | 219 (47%) | 18 (40%) | |
| 1 | 46 (10%) | 6 (13%) | |
| 2 | 69 (15%) | 4 (9%) | |
| 3 | 135 (28%) | 17 (38%) | |
| Thrombolysis In Myocardial Infarction flow grade after intervention | 0.29 | ||
| 0 | 14 (3%) | 3 (7%) | |
| 1 | 8 (2%) | 0 | |
| 2 | 16 (3%) | 3 (7%) | |
| 3 | 431 (92%) | 39 (87%) | |
| Intervention | 0.88 | ||
| Bare metal stent | 285 (61%) | 29 (64%) | |
| Drug-eluting stent | 139 (30%) | 12 (27%) | |
| Percutaneous-only balloon angioplasty | 45 (9%) | 4 (9%) | |
| Thrombus aspiration | 57 (12%) | 6 (13%) | 0.81 |
| Abciximab | 242 (51%) | 26 (58%) | 0.42 |
| Clopidogrel | 365 (78%) | 41 (91%) | 0.03 |
| Intra-aortic balloon pump | 18 (4%) | 4 (9%) | 0.12 |
| Temporary pacemaker | 13 (3%) | 3 (2%) | 0.15 |
| Orotracheal intubation | 13 (3%) | 3 (2%) | 0.15 |
| Variable | Age <75 y (n = 469) | Age ≥75 y (n = 45) | p Value |
|---|---|---|---|
| Major adverse cardiac events at 30-days of follow-up (all) | 32 (7%) | 8 (18%) | 0.009 |
| Death | 20 (4%) | 8 (18%) | 0.0001 |
| Recurrent myocardial infarction | 11 (2%) | 0 | 0.61 |
| Target vessel revascularization | 1 (0.2%) | 0 | 1.0 |
| Percutaneous coronary intervention | 0 | 0 | |
| Coronary artery bypass surgery | 1 (0.2%) | 0 | |
| (n = 435) | (n = 42) | ||
| Major adverse cardiac events at 1-year of follow-up (all) | 61 (14%) | 12 (28%) | 0.01 |
| Death | 30 (7%) | 10 (24%) | 0.0001 |
| Recurrent myocardial infarction | 11 (2%) | 0 | 0.61 |
| Target vessel revascularization | 20 (4%) | 2 (5%) | 0.70 |
| Percutaneous coronary intervention | 11 (2%) | 2 (5%) | |
| Coronary artery bypass surgery | 9 (2%) | 0 |
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
