Karla Mulder

Plaque Instability Frequently Occurs Days or Weeks Before Occlusive Coronary Thrombosis A Pathological Thrombectomy Study in Primary Percutaneous Coronary Intervention

Background—Acute ST-elevation myocardial infarction (STEMI) is caused by sudden occlusive coronary thrombosis, after plaque disruption; however, a considerable time interval between plaque disturbance and the onset of symptoms has been suggested. We therefore studied the age of intracoronary thrombi, aspirated during angioplasty in patients with acute STEMI. Methods and Results—Percutaneous intracoronary thrombectomy during angioplasty was performed in 211 consecutive STEMI patients within 6 hours after onset of anginal symptoms. The aspirated material was histologically screened on thrombus and plaque components, and thrombus age was classified as fresh (<1 day), lytic thrombus (1 to 5 days), and organized thrombus (>5 days). In all patients, intracoronary-derived material was retrieved in the filter of the collection bottle. Thrombus was identified in 199 (95%) of 211 patients. In 12 patients (5%), only plaque components were identified, and in 85 patients (41%), both thrombus and plaque material were aspirated. In 18 (9%) of 199 patients, the thrombus was organized, and in 70 patients (35%), the thrombus showed lytic changes, whereas in 98 (49%), a completely fresh thrombus was found. In 14 (7%) of 199 patients, the thrombus showed combined features of both fresh thrombus and organized thrombus. Conclusions—In at least 50% of patients with acute STEMI, coronary thrombi were days or weeks old. This indicates that sudden coronary occlusion is often preceded by a variable period of plaque instability and thrombus formation, initiated days or weeks before onset of symptoms.

Safety of low dose heparin in elective coronary angioplasty.

OBJECTIVES: To evaluate the safety of a low dose of heparin in consecutive stable patients undergoing elective percutaneous transluminal coronary angioplasty (PTCA). DESIGN: Open prospective study in a single centre. PATIENTS: 1375 consecutive patients had elective PTCA (1952 lesions: type A 11%, B1 34%, B2 36%, and C 19%). There were no angiographic exclusion criteria. INTERVENTIONS: A bolus of 5000 IU heparin was used as the standard anticoagulation regimen during PTCA. The sheaths were removed immediately after successful completion of the procedure. Prolongation of heparin treatment was left to the operators discretion. MAIN OUTCOME MEASURES: Procedural success was defined as < 50% residual stenosis without death from any cause, acute myocardial infarction, urgent coronary bypass surgery, or repeat angioplasty within 48 hours for acute recurrent ischaemia; the need for prolonged heparinisation; and the occurrence of puncture site complications. RESULTS: Procedural success without clinical events was achieved in 90% of patients. Mortality was 0.3%; coronary bypass surgery was performed in 1.7% of the procedures. The rate of myocardial infarction was 3.3%; repeat angioplasty within 48 hours was carried out in 0.7% of patients. A total of 89.1% of the patients were treated according to the protocol. Prolonged treatment with heparin was considered necessary in 123 patients (8.9%). Repeat angioplasty for abrupt closure was performed in two patients shortly after sheath removal and in two during prolonged heparinisation. Puncture site complications occurred in 2.1% of patients (low dose heparin 1.9% and prolonged heparinisation 4.9%). CONCLUSION: Elective PTCA can be safely performed using a low dose of heparin, with a negligible risk for subacute closure. Low dose heparin may reduce the incidence of puncture site complications, shorten hospitalisation, and enable out-patient angioplasty.

C-reactive protein and coronary events following percutaneous coronary angioplasty

Abstract Purpose We investigated the associations between baseline C-reactive protein levels in patients undergoing percutaneous coronary angioplasty and death, nonfatal myocardial infarction, and repeat revascularization during 14 months of follow-up. Methods In a single-center, prospective, cohort study, plasma levels of C-reactive protein were measured in 1458 consecutive patients undergoing elective or urgent coronary angioplasty. Patients were followed at 12 to 14 months for the occurrence of death, nonfatal myocardial infarction, and repeat revascularization. Results The incidence of death or myocardial infarction was 6.1% (44/716) in patients with an increased C-reactive protein level (>3 mg/L) and 1.5% (11/742) in patients with a normal level (relative risk [RR] = 4.4; 95% confidence interval [CI]: 2.2 to 8.5; P P = 0.0001). The incidence of repeat revascularization was similar in patients with or without an increased C-reactive protein level (23% [168/716] vs. 22% [163/742], P = 0.54). Statin therapy at the time of the procedure was associated with a lower mean (± SD) C-reactive protein level (5.8 ± 9.7 mg/L vs. 7.2 ± 12.1 mg/L, P = 0.02), but was not associated with the risk of death, nonfatal myocardial infarction, and repeat revascularization during follow-up. Conclusion An increased C-reactive protein level is an independent prognostic indicator for the occurrence of death or nonfatal myocardial infarction following coronary angioplasty, but is not associated with the need for repeat revascularization.

Early ambulation after coronary angioplasty and stenting with six French guiding catheters and low-dose heparin

The safety and feasibility of early ambulation was evaluated prospectively in 907 patients undergoing elective coronary angioplasty and stenting with the use of 6Fr guiding catheters, low-dose heparin (5,000 IU), and immediate postprocedural sheath removal by comparing ambulation after 4 hours with immobilization for at least 12 hours. Because no excess in puncture site complications (2.3% vs 2.2%) could be demonstrated after 4-hour ambulation, it is concluded that early ambulation after 6Fr guiding catheter angioplasty by the femoral route with low-dose heparin is feasible, safe, and may facilitate a shorter hospital stay.

Two hour ambulation after coronary angioplasty and stenting with 6 F guiding catheters and low dose heparin

Objective To evaluate the feasibility and safety of ambulation of patients two hours after elective coronary angioplasty or stenting, or both. Methods Coronary angioplasty and stenting were performed using 6 F guiding catheters by the femoral approach and a standard dose of heparin 5000 IU. There were no angiographic exclusion criteria except for planned atherectomy. Patients given oral anticoagulants or heparin were not eligible. All patients were given aspirin. Patients who underwent stent implantation also received ticlopidine 250 mg daily. The arterial sheath was removed immediately after the procedure. Haemostasis was achieved by manual compression and maintained with an inguinal compression bandage. Early ambulation was attempted after two hours of supine bed rest following removal of the bandage. Main outcome measures The incidence of bleeding at or during ambulation requiring compression and additional bed rest, and puncture site complications documented 48 hours after the procedure. Results 300 of 359 consecutive eligible patients were included for two hour ambulation. Stent implantation was performed in 32% of the procedures. The mean (SD) time to haemostasis was 9.6 (3.2) minutes. Bleeding at ambulation occurred in five patients (1.7%), and nine patients (3.0%) reached the secondary end point of haematoma > 5 × 5 cm at 48 hour follow up. All were treated conservatively without further sequelae. There was no late bleeding or vascular complications. Conclusion Ambulation two hours after elective balloon angioplasty or stent implantation with 6 F guiding catheters by the femoral route and low dose heparin is feasible and safe, with a low incidence of puncture site complications. This early ambulation protocol facilitates a short hospital stay.

Short-Term (4 Hours) Observation After Elective Coronary Angioplasty

In a prospective evaluation of the safety of short-term observation after elective percutaneous transluminal coronary angioplasty (PTCA) in 1,900 consecutive patients, 1 of 1,680 patients triaged to discharge after 4 hours of observation reached the primary end point of acute recurrent ischemia, 7 patients underwent repeat PTCA during 4 hours of observation, and 66 of 187 patients selected for prolonged observation had a complicated course. It is concluded that short-term observation after elective coronary angioplasty is safe, with a negligible risk of vessel closure after this period; triage for prolonged observation can be based appropriately on the immediate procedural result.

Does a waiting time for elective coronary angioplasty affect the primary success rate

OBJECTIVE: To evaluate the effect of the waiting time for elective percutaneous transluminal coronary angioplasty (PTCA) on the primary success rate. SETTING: University hospital in The Netherlands. PATIENTS: A cohort of 817 consecutive patients awaiting elective PTCA. Scheduled PTCA was performed in all 817 patients, involving 1237 coronary lesions. MAIN OUTCOME MEASURES: The relation between procedural success and the duration of the waiting time was evaluated. Major cardiac events, that is, death and myocardial infarction while awaiting PTCA, were documented. Alterations in lesion characteristics during the waiting time were assessed in unsuccessful procedures. RESULTS: Elective PTCA was performed within one to six weeks after acceptance in 388 patients (587 lesions; 47.5%), between six and 12 weeks in 203 patients (308 lesions; 25%), and after more than 12 weeks in 226 patients (342 lesions; 27.5%). The procedural success rates in the defined time intervals were 97%, 99%, and 97% in ACC/AHA type A lesions, 93%, 87% and 90% in type B lesions, and 63%, 55% and 38% in type C lesions respectively; 96% of type C lesions were total coronary occlusions. There was a significant decrease in primary success rate in type C lesions after a waiting time beyond 12 weeks. A reasonable explanation for an unsuccessful angioplasty related to alterations in lesion characteristics during the waiting time was documented in only four of 115 procedures. CONCLUSIONS: The primary success in type A and B lesions is unaffected by the duration of a waiting period for elective PTCA. A waiting time of more than 12 weeks is associated with a lower success rate in patients with total coronary occlusions.

Angioplasty of Chronic Total Coronary Occlusions With the Use of Six French Guiding Catheters

The efficacy of 6 French guiding catheters for angioplasty of chronic total coronary occlusions was evaluated in 61 consecutive patients. The duration of the occlusion was determined angiographically, or estimated from an index clinical event. Endpoints were procedural success, defined as recanalization with less than 50% residual stenosis without major complications; and the need to change to larger-sized guiding catheters. Recanalization was attempted in 62 chronic total occlusions; 35 were located in the left anterior descending coronary artery, 18 in the right coronary artery, and 9 in the left circumflex coronary artery. The mean duration of the occlusion was 6.0 +/- 6.6 months; the range was 2-39 months. Lesion morphology included abrupt or diffuse occlusion (55%), a side branch originating at the occlusion (47%), and bridging collaterals (23%). Death, urgent coronary bypass surgery, or myocardial infarction did not occur. Recanalization was successful in 51 of the 62 total occlusions (82%); 49 were completed successfully with a 6 French guiding catheter, and 2 were successful after changing to a larger-sized guiding catheter (which was required for peripheral vessel tortuosity in one patient, and to obtain better back-up support in another). Three other attempts remained unsuccessful after a changing. A total of 12 Palmaz-Schatz stents were implanted in 11 patients for an unsatisfactory result or type C dissection, using the same 6 French guiding catheters. These preliminary findings indicate that 6 French guiding catheters are both effective and safe for angioplasty of chronic total occlusions.