Complication rate of coronary arteriography. A review of 5250 cases studied by a percutaneous femoral technique

Intra-procedural arrhythmia during cardiac catheterization: A systematic review of literature

BACKGROUND

Cardiac catheterization is among the most performed medical procedures in the modern era. There were sporadic reports indicating that cardiac arrhythmias are common during cardiac catheterization, and there are risks of developing serious and potentially life-threatening arrhythmias, such as sustained ventricular tachycardia (VT), ventricular fibrillation (VF) and high-grade conduction disturbances such as complete heart block (CHB), requiring immediate interventions. However, there is lack of systematic overview of these conditions.

AIM

To systematically review existing literature and gain better understanding of the incidence of cardiac arrhythmias during cardiac catheterization, and their impact on outcomes, as well as potential approaches to minimize this risk.

METHODS

We applied a combination of terms potentially used in reports describing various cardiac arrhythmias during common cardiac catheterization procedures to systematically search PubMed, EMBASE and Cochrane databases, as well as references of full-length articles.

RESULTS

During right heart catheterization (RHC), the incidence of atrial arrhythmias (premature atrial complexes, atrial fibrillation and flutter) was low (< 1%); these arrhythmias were usually transient and self-limited. RHC associated with the development of a new RBBB at a rate of 0.1%-0.3% in individuals with normal conduction system but up to 6.3% in individuals with pre-existing left bundle branch block. These patients may require temporary pacing due to transient CHB. Isolated premature ventricular complexes or non-sustained VT are common during RHC (up to 20% of cases). Sustained ventricular arrhythmias (VT and/or VF) requiring either withdrawal of catheter or cardioversion occurred infrequently (1%-1.3%). During left heart catheterizations (LHC), the incidence of ventricular arrhythmias has declined significantly over the last few decades, from 1.1% historically to 0.1% currently. The overall reported rate of VT/VF in diagnostic LHC and coronary angiography is 0.8%. The risk of VT/VF was higher during percutaneous coronary interventions for stable coronary artery disease (1.1%) and even higher for patients with acute myocardial infarctions (4.1%-4.3%). Intravenous adenosine and papaverine bolus for fractional flow reserve measurement, as well as intracoronary imaging using optical coherence tomography have been reported to induce VF. Although uncommon, LHC and coronary angiography were also reported to induce conduction disturbances including CHB.

CONCLUSION

Cardiac arrhythmias are common and potentially serious complications of cardiac catheterization procedures, and it demands constant vigilance and readiness to intervene during procedures.

Pseudoaneurysm

Pseudoaneurysms (PSAs) are commonly known as complications associated with invasive interventions. Because of the pulsatile in- and outflow of blood through the neck of PSAs, they tend to grow and, in the worse cases, can rupture. Therapeutic options are compression therapy, using a compression bandage and ultrasound-guided compression, and thrombin injection. Manual ultrasound-guided compression is widely performed and is successful in most cases. In general, it is combined with a subsequently applied compression bandage. Thrombin injection is a more difficult technique, but it has a higher success rate. This article gives an overview of the characteristics of PSAs, their diagnostic characteristics and the therapeutic methods used to treat them. Complications associated with compression or thrombin injection are also explained in detail.

Prospective Study on the Incidence of Cerebrovascular Disease After Coronary Angiography

AIM

Previous studies have reported a 10.2%-22% rate of silent cerebral infarction and a 0.1%-1% rate of symptomatic cerebral infarction after coronary angiography (CAG). However, the risk factors of cerebral infarction after CAG have not been fully elucidated. For this reason, we investigated the incidence and risk factors of CVD complications within 48 h after CAG using magnetic resonance imaging (MRI) (Diffusion-weighted MRI) at Kagoshima University Hospital.

METHODS

From September 2013 to April 2015, we examined the incidence and risk factors, including procedural data and patients characteristics, of cerebrovascular disease after CAG in consecutive 61 patients who underwent CAG and MRI in our hospital.

RESULTS

Silent cerebral infarction after CAG was observed in 6 cases (9.8%), and they should not show any neurological symptoms of cerebral infarction. Only prior coronary artery bypass grafting (CABG) was more frequently found in the stroke group (n=6) than that in the non-stroke group (n=55); however, no significant difference was observed (P=0.07). After adjusting for confounders, prior CABG was a significant independent risk factor for the incidence of stroke after CAG (odds ratio: 11.7, 95% confidence interval: 1.14-129.8, P=0.04).

CONCLUSIONS

We suggested that the incidence of cerebral infarction after CAG was not related to the catheterization procedure per se but may be caused by atherosclerosis with CABG.

Iatrogenic Cardiovascular Disease Secondary to Diagnostic and Therapeutic Procedures

The number of diagnostic and therapeutic procedures performed in cardiology continues to grow. These pro cedures are generally considered safe or of minimal risk to the patient. However, it is important to remember that significant complications may occur, and in each patient the risk: benefit ratio must be carefully weighed. In this review, the complications documented in the medical literature resulting from the use of cardiologic interventions and procedures are discussed. A thorough knowledge of these complications and their precipitat ing factors can help minimize the risk to the patient.

Closure of a Popliteal Arteriovenous Fistula Using an Autologous Vein-Covered Palmaz Stent

Purpose:

To report the use of autologous vein to cover a stainless steel stent designated for repair of a traumatic popliteal arteriovenous (AV) fistula.

Methods and Results:

Autologous cephalic vein was harvested to cover a Palmaz biliary stent selected to close a traumatic popliteal AV fistula that persisted despite reparative attempts with balloon occlusion and coil embolization. The vein-covered stent was delivered percutaneously and deployed, successfully obliterating the vascular communication. Patency of the popliteal artery was documented arteriographically at 5 months, and symptomatic improvement continues at 10 months.

Conclusion:

The simplicity of this percutaneous approach and the use of autologous vein to cover endovascular prostheses create the possibility for evaluating this technique in myriad anatomical situations.

Efficacy of a single dose intravenous heparin in reducing sheath-thrombus formation during diagnostic angiography: A randomized controlled trial

BACKGROUND

Femoral arterial sheath thrombosis and distal embolization are well-recognized complications of cardiac catheterization but the occlusion is extremely rare. Heparinized saline flushes are used during diagnostic coronary angiography to prevent thrombus formation within the sheath lumen. However, the use of prophylactic intravenous heparin following the femoral arterial sheath insertion is controversial. The aim of this study is to evaluate the effectiveness of 2000 units of intravenous heparin bolus in comparison to a saline placebo on the thrombus formation within the arterial sheath during the diagnostic coronary angiography.

METHODS

Eligible patients were randomized to receive either a study drug or placebo at the time of femoral sheath insertion. The sheath was aspirated and flushed for any presence of thrombus after each catheter exchange and at the end of the procedure. Five milliliters of blood were extracted and visualized on clean gauze followed by a saline flush. The primary end-point was the effectiveness of the study drug on reducing the incidence of sheath-thrombus formation.

RESULTS

Three hundred and twenty patients were randomized into two arms. Three hundred and four patients were analyzed: 147 patients in heparin arm and 157 patients in placebo arm after exclusion of 13 patients in heparin arm and three in placebo arm because of incomplete reports. The baseline characteristics were similar and sheath-thrombi formation was observed in 20% of the total cohort. Of the heparin arm, 12% (19 patients) developed sheath-thrombus formation, whereas 26% (42 patients) in the placebo arm, p-value = 0.002. An adjusted logistic regression model showed that the only predictor for the sheath-thrombus formation was the study drug (i.e. heparin). The odds ratio of developing a thrombus in the control arm was 2.5 (95% CI: 1.4-4.5, p = 0.003). There were no bleeding events observed.

CONCLUSION

The risk of thrombus formation is significant and intravenous heparin significantly reduced thrombus formation during diagnostic coronary angiography, with no excess bleeding events.

Arterial prehabilitation: can exercise induce changes in artery size and function that decrease complications of catheterization?

Coronary angiography and angioplasty are common invasive procedures in cardiovascular medicine, which involve placement of a sheath inside peripheral conduit arteries. Sheath placement and catheterization can be associated with arterial thrombosis, spasm and occlusion. In this paper we review the literature pertaining to the possible benefits of arterial 'prehabilitation'--the concept that interventions aimed at enhancing arterial function and size (i.e. remodelling) should be undertaken prior to cardiac catheterization or artery harvest during bypass graft surgery. The incidence of artery spasm, occlusion and damage is lower in larger arteries with preserved endothelial function. We conclude that the beneficial effects of exercise training on both artery size and function, which are particularly evident in individuals who possess cardiovascular diseases or risk factors, infer that exercise training may reduce complication rates following catheterization and enhance the success of arteries harvested as bypass grafts. Future research efforts should focus directly on examination of the 'prehabilitation' hypothesis and the efficacy of different interventions aimed at reducing clinical complications of common interventional procedures.

Contemporary analysis of predictors and etiology of ventricular fibrillation during diagnostic coronary angiography

OBJECTIVES

To assess the incidence, investigate the predictors and analyze the causes of ventricular fibrillation (VF) during coronary angiography (CA) on the condition of current techniques.

METHODS

From April 2004 to January 2007, a total 22,254 patients (27,798 procedures) received CA procedures in our center; 27 patients developed VF during CA. This report was to retrospectively analyze the clinical basic characteristics, coronary angiographic characteristics and CA procedure records of these patients.

RESULTS

The incidence of VF during CA was 0.097%. The incidence of VF in radial approaches and femoral approaches was 0.076% and 0.147% (p = 0.085). The VF patients had higher coronary artery bypass grafting (CABG) rates (11.1% vs 2.3%, p = 0.024) and were more likely to have a three-vessel disease (59.3% vs 31.2%, p = 0.002) and a total occlusion lesion (25.9% vs 11.1%, p = 0.014) than non-VF patients. On logistic regression analysis, three-vessel disease (OR: 2.582, 95% CI: 1.165-5.720, p = 0.019) and the history of CABG (OR: 3.959, 95% CI: 1.160-13.513, p = 0.028) were the two independent predictors of VF occurrences. Among 27 episodes of VF, 13 were ischemia-related; 11 were manipulation-related; two were contrast-related; one was hypokalemia-related; and the causes remain unclear in five episodes.

CONCLUSIONS

The incidence of VF during CA is low on the condition of current techniques. The severity of coronary artery disease (CAD) is an independent predictor of VF occurrence during CA. Acute ischemia and inappropriate manipulation may be the two main causes in VF development.

An unusual femoral arteriovenous fistula following cardiac catheterization

The development of an arteriovenous fistula (AVF) is a rare complication of cardiac catheterization. We report a rare case with a femoral AVF following cardiac catheterization, originating from the right deep femoral artery and eventually draining into the right superficial femoral vein through the subcutaneous vein.

Efficacy and safety of percutaneous treatment of iatrogenic femoral artery pseudoaneurysm by biodegradable collagen injection

OBJECTIVES; The goal of this study was to assess the safety and efficacy of femoral artery pseudoaneurysm (FAP) closure by collagen injection. BACKGROUND; The FAP is an infrequent but troublesome complication after percutaneous transfemoral catheter procedures. If ultrasound-guided compression repair (UGCR) fails, vascular surgery is indicated. We have developed a less invasive method to close FAPs percutaneously by injecting collagen and, thus, inducing clotting within the aneurysm.

METHODS

Via a 9F needle or 11F sheath, a biodegradable adhesive bovine collagen is injected percutaneously into the FAP, guided by angiography from the contralateral site.

RESULTS

From 1993 to 2000, compression and UGCR had failed to obliterate 110 FAPs. These patients have been treated by collagen injection. Mean age of the patients was 65.6 +/- 10.2 years (range: 32 to 85 years), and 50% were women. Immediate closure of the FAP was achieved in 107/110 patients (97.3%) without any complication or adverse effect. In one patient the collagen could not be applied due to unfavorable anatomy. One patient needed a second session of collagen injection. In one patient too much collagen was inserted, which resulted in external compression of the artery, and surgical intervention was required. The overall success rate was 108/110 (98%, 95% confidence interval: 93.5% to 99.8%). Among the patients with successful procedures, there were no recurrences during six months follow-up.

CONCLUSIONS

The percutaneous treatment of iatrogenic FAP, by injection with collagen, is an effective and safe strategy. This method provides an excellent therapeutic alternative to the traditional surgical management.

Noncoronary transradial angioplasty with coronary equipment: a less invasive technique

As the safety and feasibility of the transradial approach for percutaneous coronary interventions have already been established by many series, we evaluate the safety and feasibility of this approach in noncoronary interventions such as renal, celiac, mesenteric, and subclavian angioplasty procedures. We present here our preliminary experience of noncoronary interventions via the transradial approach using coronary equipment with 100% technical and clinical success. Nine noncoronary interventions were performed in seven patients (five renal, two celiac, one mesenteric and subclavian angioplasty each). The advantage of this approach is that it limits arterial wall damage as well as potential distal embolization by the use of small guiding catheters and 0.014" guidewires. The only limitation of this approach for noncoronary interventions is the guiding catheter length in tall patients and the unavailability of large coronary balloons for subclavian, celiac, and renal interventions. With the miniaturization of equipment and improvements in technique, this approach will also become an excellent alternative for noncoronary interventions.

Coronary revascularization in Japan. Part 3: percutaneous coronary intervention during 1997

A survey by the Japanese Coronary Intervention Study (JCIS) group revealed that 109,788 percutaneous coronary intervention (PCI) procedures were performed at 1,023 laboratories during 1997. The present study aimed to describe the demographic and clinical characteristics, treatment strategies, in-hospital outcomes, and long-term outcomes of these patients. A total of 10,642 PCIs performed in 8,814 patients, which corresponded to approximately 10% of the overall PCIs, were selected at random. The mean patient age was 65 years, and 75% were males. The patients often had extensive coronary risk factors. The most prevalent clinical diagnosis was stable angina (36%), followed by myocardial infarction (MI) excluding acute myocardial infarction (AMI; 28%) and AMI (25%). Plain old balloon angioplasty was used as the sole procedure in 58% of lesions for which an attempt to heal was made, and coronary stent placement in 38%. Angiographic success was achieved in 92% of attempted lesions. Mortality, MI and emergency coronary artery bypass grafting (CABG) rates during the hospitalization were 2.6%, 2.0% and 0.7%, respectively. In-hospital mortality rate for AMI was 7.6%, whereas that for elective PCI in cases without AMI was 0.6%. The overall mortality for 1.8 years was 8%. Repeat PCI was performed for 35% and CABG for 6% during the follow-up period. In Japan, PCI was performed in patients with coronary artery disease and extensive risk factors, but a high rate of angiographic success was achieved. The rates of in-hospital mortality and emergency CABG were low in non-AMI patients, but the 1-year rate of repeat PCI was as high as 32%.

Characterization of ultrasound-detected cerebral microemboli in patients undergoing cardiac catheterization using an in vitro middle cerebral artery model

Cerebral embolization has been documented as one of the complications of diagnostic heart catheterization by transcranial Doppler (TCD). This study aimed to evaluate our hypothesis that the nature of embolic signals involved in different stages of catheter manipulation may be distinct. TCD-detected cerebral emboli occurring at different phases of cardiac catheterization were registered and differentiated by comparing their acoustic signatures with the Doppler signals generated from clinically frequently encountered embolic materials in an in vitro middle cerebral artery model. We found that there was a significant difference in embolic signal intensity and duration between different phases of cardiac catheterization. Our data suggest that different types of emboli may be involved in different phases of the catheterization. Cathet Cardiovasc Intervent 2001;53:323-330.

Use of a new diagnostic catheter for transradial internal mammary artery angiography early after minimally invasive coronary bypass

We describe a new diagnostic catheter specifically designed for selective catheterization of the left internal mammary artery via the ipsilateral radial approach. We used this catheter to assess the patency of the distal mammary-left anterior descending coronary artery anastomosis in 30 consecutive patients early after minimally invasive direct coronary artery bypass grafting. The new catheter design allowed easy and fast engagement of the left internal mammary artery leading to optimal vessel opacification in all cases. Angiography revealed graft problems in seven (23.3%) patients, two of whom required anastomosis revision, surgical in one case and with PTCA in the other. No LIMA injury occurred as a result of selective catheterization. Patients with functionally normal anastomosis were discharged on the same day of the diagnostic procedure.

Postcatheterization pseudoaneurysms and arteriovenous fistulas: repair with percutaneous implantation of endovascular covered stents

PURPOSE

To assess the effectiveness and safety of endovascular covered stents in the management of pseudoaneurysms and arteriovenous fistulas after cardiac and vascular catheterization.

MATERIALS AND METHODS

Twenty-six endovascular covered stents were used to repair 16 pseudoaneurysms, nine arteriovenous fistulas, and one combined lesion after femoral arterial puncture for diagnostic coronary angiography and/or angioplasty. Fistulas and aneurysms were in the superficial femoral artery in 16 cases, in the deep femoral artery in six cases, and in the common femoral artery in four cases. Implantation was performed from the opposite femoral artery in most cases. It was not possible to treat three additional cases transcutaneously for technical reasons (three of 29 cases).

RESULTS

Percutaneous closure of the lesions with an endovascular covered stent was successful in 26 of 29 cases. Initial follow-up showed good stent patency. Two major complications were observed after stent implantation. During follow-up (about 1 year in 23 of 26 patients [88%]), stent thromboses were detected in four of 23 patients (17%) with follow-up color duplex flow imaging.

CONCLUSION

Implantation of endovascular covered stents is an effective and safe method for the percutaneous closure of pseudoaneurysms and arteriovenous fistulas. Thus, endoluminal vascular repair with covered stents offers an alternative therapeutic approach to vascular surgery in selected patients.

[Spontaneous dissection of the coronary arteries: a rare cardiologic diagnosis]

A 55-year-old woman who was admitted to hospital with acute chest pain as a case of emergency suffered from an acute anteroseptal myocardial infarction. Four weeks later coronary angiography revealed a long dissection of the left anterior descending artery (LAD) as well as a significant stenosis of the left main and the proximal circumflex. Cardiovascular surgery was done subsequently. In addition to myocardial revascularization using coronary artery bypass grafts a readaptation of the dissecting artery walls and a proximal ligation of the LAD before anastomosis were performed. Clinical data, pathogenesis, and indications for medical and surgical treatment of spontaneous artery dissection are presented.

A prospective, randomized evaluation of nonsurgical closure of femoral pseudoaneurysm by compression device with or without ultrasound guidance

Femoral artery pseudoaneurysm (PA) is a significant complication following diagnostic or therapeutic catheterization. The treatment of choice for femoral artery PA is freehand ultrasound-guided compression repair (UGCR). An alternative method is compression by mechanical devices. The study evaluated the mechanical compression device (FemoStop) with (G1) or without (G2) ultrasound guidance for initial placement in a randomized fashion. Thirty-eight patients (20 women, 18 men) age 40 to 85 (mean 54) years with clinical signs of PA underwent diagnostic color Doppler ultrasound. Randomization yielded 19 patients each for G1 and G2. PA occurred after 12 diagnostic cardiac catheterizations, 18 coronary stent implantations or balloon angioplasties, 2 electrophysiology procedures, and 6 peripheral percutaneous transluminal angioplasties. The G1 protocol was successful in 15 of 19 patients (79%), with a mean compression time of 28 min. The three other patients were treated successfully with UGCR. Only one patient needed vascular surgery. The G2 protocol was successful in 14 of 19 patients (74%) with a mean compression time of 33 min. The failed patients were treated successfully: three with UGCR and two with the same mechanical compression device now positioned under ultrasound control. Compression therapy with the compression device (FemoStop) for iatrogenic femoral pseudoaneurysm does not require ultrasound guidance for positioning. Cathet. Cardiovasc. Intervent. 47:304-309, 1999.

Diagnostic cardiac catheterisation in a hospital without on-site cardiac surgery

OBJECTIVE

To assess the feasibility, safety, and clinical impact of diagnostic cardiac catheterisation in a multipurpose laboratory in a district general hospital without cardiac surgery.

METHODS

A prospective audit of the first 2000 consecutive cases between September 1992 and March 1997. Unstable patients were referred to a surgical centre for investigation, in line with subsequently published British Cardiac Society (BCS) guidelines, but all other patients requiring cardiac catheterisation were investigated locally and are included in this report. The function of the laboratory was also compatible with the BCS guidelines regarding staffing, operators, equipment, number of cases, and locally available vascular surgery.

RESULTS

Of the 2000 cases, 1988 studies were completed (99%), 1985 (99%) included coronary angiography, and 1798 (90%) were performed as day cases. Left main stem disease was present in 157 (8%), three vessel disease in 683 (34%), two vessel disease in 387 (19%), single vessel disease in 424 (21%), and normal coronary arteries in 494 (25%). Of the latter, 284 (14% of the total) had another cardiac diagnosis for which they were investigated (for example, valvar heart disease). Referral for cardiac intervention following catheterisation was made in 1172 of the 2000 cases (intervention rate 59%; catheter:intervention ratio 1. 7:1). The interventions performed were coronary artery bypass grafting (CABG) in 736 of the 1172 cases (63%), other types of cardiac surgery in 122 (10%), combined CABG and other cardiac surgery in 71 (6%), and percutaneous transluminal coronary angioplasty in 243 (21%). There were two catheter related deaths (0. 1%), both of which occurred within 24 hours of the procedure, and a further nine major cardiovascular complications with residual morbidity (0.45%). These were myocardial infarction in two (0.1%), cerebrovascular events in two (0.1%), and surgical vascular complications in five (0.25%). In addition, there were eight successfully treated, life threatening arrhythmias (0.4%).

CONCLUSIONS

Diagnostic cardiac catheterisation can be performed safely and successfully in a local hospital. When BCS guidelines are followed, the mortality is similar to published pooled data from regional centres (0.1% v 0.12%). The high intervention rate indicates a persistent unmet demand in the districts, which will continue to affect surgical and interventional services.

Cerebral microemboli during left heart catheterization

BACKGROUND

The aim of this study was to describe the rate of microemboli signals (MES) during left heart catheterization (LHC).

METHODS

A monitoring of both middle cerebral arteries using transcranial Doppler ultrasonography was performed to investigate cerebral microemboli during LHC. Seventy-two patients undergoing LHC and 29 patients with LHC followed by coronary intervention were studied.

RESULTS

During a standardized LHC (n = 52), 95 +/- 45 MES were detected of which 67.5% occurred during injection of contrast media or saline solution, 30% during movements of wire and catheter, and 2% during catheter manipulation. During coronary interventions only, rotablation (n = 2) was followed by a massive increase in MES. The use of injection fluids prepared with minor gas content reduced the MES rate by 67% (P <.05). All MES were clinically silent.

CONCLUSIONS

Cerebral microembolism is a current finding during LHC. The dependence of the MES rate during diagnostic LHC on the gas content of the injection fluids provides evidence that most of the MES are caused by microbubbles and not by solid emboli. The high rate of MES during coronary rotablation may be explained by the formation of cavitation bubbles. The clinical results of the MES during LHC appear to be benign.

A randomized trial of vascular hemostasis techniques to reduce femoral vascular complications after coronary intervention

This report details a prospectively randomized clinical trial comparing mechanical clamp compression to hand applied pressure for attaining vascular hemostasis after coronary intervention. Effectiveness was determined by comparing the incidence of femoral vascular complications resulting from each of the 2 techniques. Eligible participants included 778 consecutive patients scheduled for percutaneous coronary intervention over an 8-month period. An unselected cohort of the eligible patients (n = 592), determined by the availability of cross-trained clinicians, underwent follow-up serial physical examinations by blinded observers for the duration of their hospital stay. A second, similarly determined cohort (n = 390), underwent color-duplex ultrasonography within 24 hours of sheath removal. Baseline demographic and clinical characteristics, sheath removal parameters, and subsequent outcomes were collected prospectively. The primary end point was a composite of ultrasound-defined femoral vascular complications: femoral artery thrombosis, echogenic hematoma, pseudoaneurysm, or arteriovenous fistulae formation. Complications diagnosed by physical examination constituted the second fundamental end point and included: persistent oozing, ecchymosis, hematoma, bruit, and pulsatile mass. Compared to manual compression, mechanical clamp hemostasis reduced the primary adverse end point by 63% (p = 0.041). Physical examination detected ecchymosis, oozing, and hematomas at equally high frequencies in the two cohorts. Although 65% of the patients in both treatment groups encountered at least one of these cosmetic complications, the diagnoses made by physical examination did not correlate with ultrasound-defined pathology. Multivariable stepwise logistic regression analysis identified a relationship of advanced age and lower body weight to vascular complications. Utilization of a mechanical clamp rather than conventional hand pressure to attain vascular hemostasis significantly reduces ultrasound-defined femoral vascular pathology. Discrepancies between physical examination and ultrasound diagnoses challenge the utility of clinical assessment alone and establish ultrasound as the diagnostic modality of choice.

Outpatient coronary angiography: indications, safety, and complication rates

In the years since the introduction of outpatient cardiac catheterization and coronary angiography, the indications for the use of these procedures have expanded rapidly with advancements in surgical and endovascular procedures. The safety of outpatient coronary angiography has been well established, comparing very favorably with that of inpatient procedures. At present, a variety of different outpatient facilities exist. Catheterization laboratories may adjoin a hospital or be free-standing; the safety and success of procedures performed in mobile cardiac catheterization laboratories has also been described. There are a variety of access techniques for cardiac catheterization in use today, and there are many types and sizes of catheters available. Miniaturization of equipment has reduced complications and allowed early ambulation and discharge from outpatient laboratories. In addition, the development and refinement of catheters and techniques for achieving hemostasis may allow further reductions in patient stay and complications. The complication rates of outpatient cardiac catheterization and coronary angiography are, in fact, quite low--in some cases, lower complication rates are seen in the outpatient population than in the inpatient population. Although this is certainly related in part to the fact that outpatients generally have more stable disease, it is clear that careful equipment choices, proper technique, and adequate monitoring have contributed to the success of these important outpatient procedures.

Transient left bundle branch block induced by left-sided cardiac catheterization in patients without pre-existing conduction abnormalities

A traumatic left bundle branch block (LBBB) is uncommon in a patient with intact atrioventricular conduction. Three of our patients developed LBBB during a left-sided catheterization. Two patients suffered from angina pectoris and the other had an abdominal aneurysm. Two of them had a history of hypertension. None of the patients had ever shown any conduction abnormalities before the catheterization. The electrocardiogram just before the examination was normal in all 3 patients. LBBB was observed when a catheter was introduced into the left ventricle, and lasted 2--4 min without significant change in heart rates. Examination revealed no significant stenosis proximal to the first septal perforator and normal left ventricular contraction in all patients. One patient developed permanent LBBB 14 months later. Catheter-induced LBBB may occur easily with certain anatomical characteristics of the left bundle branch or the distal His bundle, with or without some concealed damage to the conduction system. It is important to keep this complication in mind and to pay adequate attention to patients' electrocardiograms as well as their angiographical findings, especially in those with pre-existing right bundle branch block.

[Peripheral arterial complications after heart catheterization]

After diagnostic and interventional cardiac catheterization, local vascular complications at the arterial entry site must be expected. With respect to the method applied for catheterization and the puncture site, the type of complications may vary. With transfemoral approach a large variety of vascular complications have to be feared, mostly in the form of bleeding complications and hematomas, arterial dissections or occlusions, pseudoaneurysms and AV-fistulas. Each of these complications may have the potential for serious morbidity. When cardiac catheterization is performed via the arteries of the arm (either in the classical Sones technique by arterial cutdown to the brachial artery or by direct puncture of the brachial or radial artery) vascular occlusions will mostly occur as local vascular complications. These occlusions can often be managed conservatively or by a surgical procedure. The incidence of a vascular complication is mainly dependent on patient-related (sex, age, height, weight, arterial hypertension, diabetes, presence of peripheral vascular disease and compliance of the patient after withdrawal of the sheath) and procedure-related (arterial access site, diagnostic or interventional study, sheath size, periprocedural anticoagulation, duration of intra-arterial sheath placement, faulty puncture technique, operator skill) factors. In addition, the definition of a complication, the publication year of a certain study and the technique used for identification of complications seem to play a role for the reported incidence of peripheral vascular complications after cardiac catheterization. Currently, incidences of 0.1 to 2% for significant local vascular complications after diagnostic transfemoral catheterization are reported, after interventional transfemoral treatment 0.5 to 5% and after complex procedures using large sheath sizes with periprocedural anticoagulation (directional atherectomy, IABP, left-heart assist, valvuloplasty) up to 14%. Following transbrachial and transradial catheterization, local vascular complications at the entry site amount to 1 to 3% after diagnostic and 1 to 5% after interventional procedures. Local vascular complications may be diminished by a cautious and sensitive puncture technique with additional care in patients at higher risk for vascular complications (females, prediagnosed peripheral vascular disease, mandatory anticoagulation, necessity for large sheaths). By using smaller sized catheters and an adequate, defensive anticoagulation regimen, the rate of arterial access site complications may be reduced. Proper methods for achievement of hemostasis as well as a close and careful observation after sheath withdrawal are required.

Rapid hemostasis of arterial puncture sites with collagen in patients undergoing diagnostic and interventional cardiac catheterization

Despite the continuous reduction of sheath sizes in diagnostic and interventional cardiac catheterizations and the discontinuation of coumadin use after coronary stent implantation, a challenging role remains for hemostatic devices in the sealing femoral puncture sites. Since the introduction of the vascular hemostatic device (VHD) in 1991 and the hemostatic puncture closing device (HPCD) in 1992, numerous studies investigating these devices have been published. The deployment success rates reported in 2,292 patients for VHD is 97%, ranging from 88 to 100%. For HPCD, the mean deployment success rate resulting from 622 published patients leads to an identical result of 97%, ranging between 91 and 100%. For time to hemostasis, data have been analyzed according to the four different clinical situations, depending on level of anticoagulation (none or full) and the time of sheath removal (immediate or delayed). In randomized studies, when compared with the manual control groups, both devices revealed a statistically significant reduction in time to hemostasis: 12 to 16 minutes less for diagnostic catheterization and 14 to 30 minutes less for PTCA. As for minor local complications, no clinically relevant differences seem to exist. None of these devices has been proven to reduce major local complications. Prospective trials addressing early mobilization after percutaneous transluminal coronary angioplasty and the cost effectiveness of arterial closure devices in defined subgroups are warranted.

Treatment of iatrogenic femoral artery pseudoaneurysm with percutaneous thrombin injection

PURPOSE

Local compression has been advocated for the treatment of femoral artery pseudoaneurysms. Although it is effective and has a high success rate, this method bears some limitations; among them are prolonged procedure time, discomfort for patients, and recurrence. As a potent thrombosis-inducing agent, thrombin has been used topically, and occasionally intravascularly, for hemostasis. Pseudoaneurysms with a narrow connecting tract to the native artery may be suitable for treatment with thrombin injection to induce intracavitary coagulation.

METHODS

Patients with pseudoaneurysms of the femoral artery were evaluated by ultrasonography. Under ultrasound guidance, an intravenous catheter was introduced percutaneously into the pseudoaneurysm, with the catheter position confirmed by contrast ultrasonography. One thousand units of thrombin dissolved in normal saline solution was then injected slowly into the pseudoaneurysm through the catheter to induce thrombosis. The patients were monitored closely for any adverse effects after thrombin injection.

RESULTS

A total of five patients with femoral artery pseudoaneurysms were treated with direct percutaneous thrombin injection under ultrasound guidance. Within seconds of thrombin injection thrombus formation was evident, and blood flow in the pseudoaneurysm soon ceased when the thrombosis extended to the connecting tract. All procedures were uneventful and successful. No recurrence was noted during follow-up periods of 1 to 28 months.

CONCLUSION

Our initial experience with the small number of patients demonstrates the simplicity, lack of morbidity, and high success rate for ultrasound-guided percutaneous thrombin injection for the treatment of femoral artery pseudoaneurysms.

Pseudoaneurysm after cardiac catheterization: therapeutic interventions and their sequelae: experience in 86 patients

After diagnostic cardiac catheterization in 8,715 patients, a pseudoaneurysm was diagnosed in 86 (1%) patients. Primary conservative management by repeated compression bandages (CB) or ultrasound guided compression (UGC) was attempted in all patients. Occlusion of the pseudoaneurysm was achieved significantly more often by UGC (41/47; 87%) than by CB (22/39; 56%; P = 0.016). Of 86 patients, 23 (27%) required surgical treatment. Major clinical acute complications occurred after surgery in 8/23 cases (35%) versus 4/63 (6%; P = 0.0004) following successful CB or UGC. However, intention-to-treat analysis showed no difference in the rate of acute complications in the CB or UGC group (15.4% versus 12.8%, P = 0.7272), because of a trend towards a higher complication rate following secondary surgery in the UGC (4/6 = 66.7%), as compared to the CB group (4/17 = 23.5%, P = 0.1589). During follow up, 22/64 (34%) patients reported persistent inguinal complaints, 9/15 (60%) after surgery and 13/49 (27%) after successful CB or UGC (P = 0.0169). However, according to the intention-to-treat analysis, there was no significant difference between the initial groups (CB: 26.1% versus UGC: 39.0%, P = 0.2958). Despite a higher effectiveness of UGC to achieve occlusion of a pseudoaneurysm compared to CB (87% vs. 56%), UGC is not superior to CB because of a higher rate of acute complications as well as long-term complaints in those patients requiring secondary surgery in the UCG group as compared to the CB group.

Local venous thrombosis after cardiac catheterization

Pulmonary embolism is a rare but life-threatening complication of cardiac catheterization. Underlying deep venous thrombosis (DVT) is often not detectable clinically. To determine the true incidence of DVT the authors prospectively studied 450 consecutive patients (29% women, 71% men, mean age: fifty-eight years) undergoing a diagnostic cardiac catheterization. Patients were examined clinically and by duplex sonography with a high-resolution (5 or 7.5 MHz) transducer before and twenty-four hours after catheterization before mobilization. Duplex sonography excluded complete proximal DVT in all patients. Only partial occluding thrombi (pDVT) were detected in 11 (2.4%) patients. The thrombi were always localized at the puncture site. In 2 patients a difference was found in the circumferences of the legs, but no other clinical signs of DVT were seen. With use of continuous wave (cw) Doppler sonography, only 3 of these 11 patients (27%) showed a spontaneous (s) sound. Phlebography was performed in 4/11 patients (36%). In 2 patients the diagnosis was confirmed; in 1 patient extravenous compression was assumed, and the other demonstrated a normal-appearing phlebography at the time of investigation. Logistic regression analysis yielded a 3.5 times higher risk for developing a pDVT if a venous puncture was performed in addition to arterial puncture. Furthermore a 9.8 times higher risk was found if more than one venous puncture was necessary. During the follow-up no patient developed clinical signs of pulmonary embolism. The results of this study demonstrate that DVT is a rare complication of cardiac catheterization (0/450 patients), but pDVT occurred in 2.4%. Risk factors for pDVT are the venous puncture itself and multiple puncture attempts. Clinical relevance of pDVT remains to be determined.

Ultrasound-guided compression repair for treatment of femoral artery pseudoaneurysm: acute and follow-up results

Femoral artery pseudoaneurysm is a significant problem in patients undergoing arterial diagnostic or therapeutic catheterization. The aim of this investigation was to report the incidence of pseudoaneurysm after arterial catheterization and the success rate of ultra-sound-guided compression repair. During a 3-year period (11/91-11/94) 9,051 patients underwent 7,312 cardiac catheterizations and 1,739 peripheral percutaneous transluminal coronary angioplasty procedures. Patients suspect of pseudoaneurysm were referred for a color Doppler ultrasound examination. All patients with pseudoaneurysm were considered for ultrasound-guided compression repair. Pseudoaneurysm occurred more frequently after interventional procedures with new devices (valvuloplasty 2.3%, stent 3.2%) than after conventional catheterization diagnostic cardiac catheterization 0.2%, electrophysiology 1.3%, percutaneous transluminal coronary angioplasty 0.2%). The incidence of pseudoaneurysm after peripheral percutaneous coronary transluminal angioplasty, including intra-arterial lysis and stent, was 1%. Ultrasound-guided compression repair was successfully performed in 37 of 41 cases with pseudoaneurysm (90%). Ultrasound-guided compression repair was successfully performed in 30 of 31 patients (97%) without anticoagulation and in 7 of 10 patients (70%) receiving anticoagulants (P < 0.05). There was no correlation between mean diameter of the pseudoaneurysm, age of the lesion, or antiplatelet therapy. Color Doppler ultrasound re-examination at up to 3 months indicated successful treatment in all patients. The use of complex interventional catheterization procedures leads to an increased frequency of pseudoaneurysms compared with conventional angiography and percutaneous transluminal coronary angioplasty. Ultrasound-guided compression repair is a non-invasive, efficient, safe and cost-effective therapy for post-catheterization pseudoaneurysm.

Is a baseline electrophysiologic study mandatory for the management of patients with spontaneous, sustained, ventricular tachyarrhythmias?

Should the patient being treated for spontaneous, sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) routinely undergo a baseline, diagnostic, catheter electrophysiologic (EP) study? The potential patient advantages of such a policy include identification of the tachyarrhythmia-initiating episodes of presumed VT or VF, prediction of the subsequent risk of VT/VF recurrences, identification of VT mechanisms amenable to cure by catheter ablation, assessment of the response of a patient's VT to attempts at pace termination, evaluation of the patient's candidacy for some of the approaches to VT/VF therapy selection, and enhancement of our understanding of the mechanisms and therapeutics of VT/VF. Disadvantages of such a policy include patient discomfort, patient risks, and cost. Recognizing that the decision to perform a baseline catheter EP study in a patient with VT/VF must be based on an individualized, patient-based, risk-benefit analysis; this review details each of the advantages and disadvantages of doing so to identify patient populations for whom a baseline catheter EP study is or is not usually indicated.

Outpatient cardiac catheterisation

Cardiac catheterisation is increasingly performed in an outpatient setting. The majority of series of outpatient cardiac catheterisation are in laboratories with immediate access to cardiovascular surgery. However, some units may be sited more distantly, although still generally close to a hospital. Compared to an inpatient procedure, outpatient cardiac catheterisation increases bed availability and there are considerable financial rewards with suggested savings of 11-54% of inpatient costs. Most patients are satisfied with an outpatient procedure and, although a quarter may have unanswered questions afterwards, this level may not differ from that found with inpatients. No study has been large enough to detect differences in the major complication rate which occur infrequently in whichever setting, and there is considerable variation between studies in the incidence of minor complications after outpatient procedures. In the only study which randomised all eligible patients to an inpatient (189 patients) or outpatient (192 patients) procedure, seven outpatients (3.6%) suffered bleeding or developed haematomas at the site of percutaneous femoral artery puncture towards the end of the mobilisation period and one patient was syncopal. These events were thought to be a direct result of the procedure being carried out in the outpatient setting. The proportion of patients considered eligible for outpatient cardiac catheterisation varies widely between different series from 20% to more than 80%. Whereas some of this variation may result from the implementation of different exclusion criteria for patients with potentially severe disease, the differences are so large that it is likely that different populations were studied. Unplanned admission rates varied from less than 1% to nearly 19%. With the currently available data no absolute guidelines can be derived to exclude all patients at risk of complications, but the American College of Cardiology/American Heart Association (ACC/AHA) task force recently published guidelines which identified low risk patients suitable for outpatient procedures. These guidelines have been used to select patients for investigation in two mobile units in the USA, and only 0.9% required urgent transfer for clinical instability, and 0.6% developed major complications. However, most patients did not need referral to a tertiary centre for additional procedures and there may be less scope for selecting patients within the ACC/AHA guidelines in the UK compared with the USA.

Effects of modified positioning and mobilization of back pain and delayed bleeding in patients who had received heparin and undergone angiography: a pilot study

OBJECTIVE

To examine the effects that a modified positioning and mobilization routine had no back pain and delayed bleeding in patients who had received heparin and undergone cardiac angiography.

DESIGN

An experimental research design was used. Each patient was assigned randomly to either the control group, which required 6 hours of bed rest after cardiac angiography, or the experimental group. The experimental group had modified positioning, in which the head of the bed was elevated to a maximum of 45 degrees, and modified mobilization, in which they were ambulated briefly at the bedside 4 hours after angiography.

SETTING

Two cardiology units of a 700-bed urban teaching hospital in western Canada.

SAMPLE

All patients admitted for nonemergent cardiac angiography were approached for consent, to attain a sample of 29 patients, and were randomly assigned to the experimental or the control group.

METHOD

Each patient was randomly assigned before cardiac angiography. The assignment was confidential until the patient was admitted to the cardiac unit after angiography. A demographic tool and the McGill Present Pain Intensity Scale were used to collect data. Perception of pain was evaluated over four observation periods. A research assistant monitored sanguineous drainage on the dressing and hematoma to evaluate the presence of delayed bleeding.

DATA ANALYSIS

Demographic information was analyzed primarily through descriptive statistics. Results were analyzed to compare back pain and delayed bleeding between the two groups. Wilcoxon scores and t tests both were used for analysis and correlated well with each other.

RESULTS

The group with the modified positioning and mobilization routine experienced significantly less pain overall (p = 0.02), less pain at each interval, and significantly less pain intensity (p < 0.05). There was no difference in bleeding. One person in each group had an estimated blood loss of more than 100 ml through the pressure dressing.

CONCLUSION

This pilot study supports our hypothesis that modifying the immobilization of patients after cardiac angiography is associated with a reduction in back pain and with no increase of delayed bleeding at the femoral access site. The results support the need for further investigation of ambulation interventions after cardiac angiography.

Ultrasound-guided compression closure of postcatheterization pseudoaneurysms during concurrent anticoagulation: a review of seventy-seven patients

PURPOSE

Data from our institution and elsewhere have demonstrated that ultrasound-guided compression closure (UGCC) is an effective method of treating postcatheterization pseudoaneurysms. Whereas patients receiving anticoagulation do not have as high a success rate as those not receiving anticoagulants, there have been no large series evaluating the factors associated with success or failure in patients receiving anticoagulation. The purpose of this study is to determine whether uninterrupted anticoagulation interferes with successful UGCC of pseudoaneurysms and to identify factors associated with success or failure.

METHODS

From May 1991 to September 1994, 238 cases of attempted UGCC of pseudoaneurysms were performed in our vascular laboratory. Only patients who received uninterrupted heparin, warfarin, or both at the time of pseudoaneurysm compression were eligible for inclusion into the study. Seventy-seven patients were identified who met the study criteria.

RESULTS

Successful pseudoaneurysm compression was obtained in 56 (73%) patients, whereas 21 (27%) patients had a failed UGCC. In the successfully treated group, seven (12.5%) required between two to three compression attempts to induce sustained thrombosis. There was no statistical difference in age, sex, sheath size, days after procedure, location of pseudoaneurysm, or number of chambers in the pseudoaneurysm between those patients who had a successful repair and those who did not. If the pseudoaneurysm was less than 4 cm in diameter, 51 of 65 patients (78%) had a successful repair compared with 5 of 12 patients (42%) with a pseudoaneurysm of 4 cm or greater (p = 0.013). There was no statistical difference between success and failure in patients receiving warfarin alone (3.73 mean international normalized ratio, 72% success rate), heparin alone (mean activated partial thromboplastin time of 63 seconds, 92% success rate), or heparin and warfarin (mean activated partial thromboplastin time of 70 seconds, mean international normalized ratio of 4, success rate of 67%). No arterial or venous thrombosis occurred during pseudoaneurysm compression.

CONCLUSION

Successful UGCC of pseudoaneurysms occurred in a large percentage of patients receiving full-dose, uninterrupted anticoagulation. The only factor influencing success was the size of the pseudoaneurysm.

Closure of a popliteal arteriovenous fistula using an autologous vein-covered Palmaz stent

PURPOSE

To report the use of autologous vein to cover a stainless steel stent designated for repair of a traumatic popliteal arteriovenous (AV) fistula.

METHODS AND RESULTS

Autologous cephalic vein was harvested to cover a Palmaz biliary stent selected to close a traumatic popliteal AV fistula that persisted despite reparative attempts with balloon occlusion and coil embolization. The vein-covered stent was delivered percutaneously and deployed, successfully obliterating the vascular communication. Patency of the popliteal artery was documented arteriographically at 5 months, and symptomatic improvement continues at 10 months.

CONCLUSION

The simplicity of this percutaneous approach and the use of autologous vein to cover endovascular prostheses create the possibility for evaluating this technique in myriad anatomical situations.

Maintenance fluids in prehospital care: crystalloid versus dextrose solutions--is there a difference?

D5W is the maintenance fluid often used in prehospital care when transporting patients with cardiac or central nervous system processes. However, there is evidence that dextrose solutions are potentially harmful, and that suggests isotonic crystalloid solutions are the preferred maintenance fluid in treating emergent patients regardless of their underlying disease. Dextrose solutions may exacerbate cellular ischemic damage and they cannot be used to resuscitate hypotensive patients. Crystalloids do not cause fluid overload when used at maintenance rates and are effective resuscitative agents in managing hypotension. The use of a single crystalloid solution in the prehospital environment would simplify equipment stocking and management protocols, minimize cost, and would not have an adverse impact on patient care.

Postarteriographic femoral pseudoaneurysms: treatment with ultrasound-guided compression

Pseudoaneurysms following femoral arterial catheterization are increasingly common and are related to factors such as catheter size, periprocedural anticoagulation, hypertension, and improper technique. Ultrasound-guided compression as a noninvasive technique for repair of these lesions was prospectively evaluated in 16 patients whose mean age was 61 years. Nine patients were on anticoagulants and six had hypertension. All patients presented with an enlarging groin hematoma, a pulsatile mass, and/or a bruit following femoral catheterization. Seventeen femoral artery pseudoaneurysms, including one with an associated arteriovenous fistula, were detected using color-flow Doppler imaging. Three pseudoaneurysms thrombosed spontaneously. The remaining 14 were managed with compressive therapy lasting from 20 to 100 minutes. No complications were encountered during the compressions and 10 false aneurysms (71%) responded completely (mean time to thrombosis of 38 minutes). Two lesions responded partially to compression and there were two failures, the latter associated with excessive anticoagulation in one patient and a well-established pseudoaneurysm in the second patient. Only one pseudoaneurysm (6%) in the series required surgical correction. Ultrasound-guided compression of acute pseudoaneurysms in the groin is a safe, inexpensive, and effective method of treatment.

Mobile cardiac catheterization registry: report of the first 1,001 patients

The purpose of this study was to evaluate prospectively the efficacy and safety of mobile cardiac catheterization. Mobile cardiac catheterization was introduced into clinical practice in 1989, but there has been no systematic study of its performance and safety. A registry was established in 1989 to monitor outcomes with mobile cardiac catheterization and is reported here. Patients were screened for eligibility for mobile cardiac catheterization using the joint AHA/ACC criteria for outpatient angiography. Eligible patients underwent mobile catheterization at eight hospitals within 120 miles of the base tertiary center. Helicopter evacuation services were available at each mobile site. The indications, findings, dispositions, and complications of mobile cardiac catheterization were recorded by means of a checklist, telephone follow-up and chart review. A total of 1,001 consecutive patients were entered into the registry in the first 20 months of operation, including 436 females and 565 males aged 22 to 84 years. Angina (Canadian Classes II-IV) was the most frequent primary indication for catheterization (46.4%), followed by atypical chest pain (36.9%), or a positive exercise stress test (25.6%). Infrequent indications for catheterization included a history of myocardial infarction (5.6%), congestive heart failure (7.1%), arrhythmias (4.1%), and valvular heart disease (0.7%). Catheterization was accomplished in 99.9% of patients. Angiographically normal studies were observed in 22.8%, and mild (< or = 50%) coronary artery disease in 13.6% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinically guided closure of femoral arterial pseudoaneurysms complicating cardiac catheterization and coronary angioplasty

Femoral artery pseudoaneurysm formation is a significant problem in patients undergoing cardiac catheterization and interventional cardiac procedures. It is especially more common with the use of anticoagulant and antiplatelet therapy and the use of intracoronary stents. We describe our initial experience with clinically guided bedside compression of femoral pseudoaneurysms in such patients. Eleven patients, 10 undergoing coronary angioplasty (including 3 with intracoronary stents) and 1 undergoing diagnostic cardiac catheterization, developed a femoral pseudoaneurysm. All patients had a femoral bruit and 9 had an expansile groin hematoma. The diagnosis was confirmed in each case by Doppler ultrasound. Seven patients were receiving heparin while 4 were on oral anticoagulants at the time of detection of the pseudoaneurysm. These patients underwent clinically guided graded external compression to close the pseudoaneurysm neck while maintaining femoral arterial flow. External compression for 104.1 +/- 63 min resulted in successful clinical resolution of pseudoaneurysm in all patients without complications. The results were confirmed by Doppler ultrasound at least 12 hr later. Bedside compression of femoral pseudoaneurysms guided by clinical clues is simple and appears to be an effective and safe technique to manage this iatrogenic problem.

A new hemostatic puncture closure device for the immediate sealing of arterial puncture sites

After angiography, 6 to 24 hours of bedrest is indicated to assure that adequate hemostasis of the femoral artery has been achieved. Recently, a new hemostatic puncture closure device (HPCD) has been developed, which consists of a resorbable polymer anchor, a resorbable suture, a small collagen plug and an 8Fr delivery device. The device is delivered into the femoral artery through the introducer sheath, the anchor is secured against the intraluminal artery wall, and the collagen plug is deployed on the arterial wall. The prototype of the HPCD was used in 20 patients administered heparin. After insertion of the HPCD, hemostasis was achieved in 1.2 +/- 2.1 minutes; in 2 patients a light pressure dressing was applied for 4 hours to stop oozing. No late bleeding occurred. In 1 patient the positioning suture broke, requiring the application of a pressure bandage. Patients were uneventfully mobilized after 6.7 +/- 3.5 hours. In all patients serial duplex scanning of the femoral artery was performed before and after 1, 7, 30 and 90 days after HPCD placement. In 5 patients a small subcutaneous hematoma close to the site of introduction could be detected by ultrasound 1 day after catheterization. All but 1 patient had normalization of the flow patterns in the femoral artery. It is concluded that: (1) the HPCD is an effective device to achieve immediate hemostasis after arterial catheterization despite antithrombotic therapy, (2) early mobilization was uneventful, (3) duplex ultrasound studies demonstrated only transient changes in the punctured femoral artery, and (4) further investigations are needed to establish the efficacy and safety of the device.