Randomized evaluation of four versus five French catheters for transfemoral coronary angiography

A serious complication of a power injector for coronary angiography

Recently several contrast delivery systems for coronary angiography have been introduced to provide adequate artery opacification through small catheters, which are thought to facilitate patient comfort and reduce hemorrhagic/vascular complications. However, the safety profile of a specific system has not been fully examined. In this case report, we present patients who underwent angiography using a contrast delivery system and suffered from massive air embolism necessitating mechanical support. We discuss the potential mechanism and the prevention of this complication.

Measuring pressure-derived fractional flow reserve through four French diagnostic catheters

Measurement of fractional flow reserve (FFR) with a pressure wire is used to discriminate between patients with and without functionally significant lesions. FFR can be assessed through a conventional 4Fr diagnostic catheter, which is a more convenient method of assessment. The aim of this study was to assess the feasibility, safety, repeatability, and reliability of routine FFR measurements through 4Fr diagnostic catheters. From a single-center prospective registry, results of FFR assessment through a 4Fr catheter were used to determine: (1) feasibility and safety, by the procedural success rate and immediate and 30-day clinical outcome; (2) repeatability, by the intraclass correlation coefficient and comparison of the difference (means +/- 2 SDs); and (3) reliability, by comparison of results obtained using 4Fr versus 7Fr guiding catheters. During the study period, FFR was measured in 190 patients, in 122 using a diagnostic 4Fr catheter (study population) and in 68 using a 7Fr guiding catheter. Measurement of FFR wa successful in 115 of 122 patients (94%). No complications related to the use of the 4Fr catheter occurred. Repeatability was determined from 108 repeated measurements: the intraclass correlation coefficient was 0.942 and the mean difference between repeated FFR measurements was -0.001 +/- 0.038. Reliability was determined from 15 unselected patients; there was no systematic error and only 1 value was out of the range of 2 SDs of the mean difference. Using a threshold value of 0.75, the Kappa coefficient for the qualitative agreement was 0.84. Thus, pressure-derived FFR assessment can safely be performed through 4Fr diagnostic catheters, with similar repeatability and reliability as 7Fr guiding catheters, resulting in a simplification of the measurement procedure.

Procedural complications following diagnostic coronary angiography are related to the operator's experience and the catheter size

Cardiac catheterization is performed routinely in hospitals all around the world. Extensive analysis of complications has been performed in the 1980s and early 1990s. However, because of the new therapeutic innovations based on advanced catheter technologies, these data may not apply to the present situation. Still, there are few data about procedural complications of diagnostic cardiac catheterization over the last 10 years. A total of 7,412 consecutive diagnostic cardiac catheterizations were performed between January 1990 and December 2000 and prospectively assessed in a registry. There were a total of 63 complications, of which 40 were minor and 23 major. Thus, the overall complication rate was 0.8%, with a mortality rate of 0%. Univariate analysis showed lower overall complication rate of senior physicians (> 500 coronary angiographies performed; OR = 0.58; 95% CI = 0.34-0.98; P = 0.04), smaller catheter size (< 6, 6, > 6 Fr: OR = 2.6; 95% CI = 1.53-4.41; P = 0.0004), and a higher rate in patients having left and right heart catheterization (OR = 2.62; 95% CI = 1.46-4.7; P = 0.003). Major complications were associated with larger catheters (< 6, 6, > 6 Fr: OR = 2.35; 95% CI = 1.0-5.51; P = 0.05), whereas vascular complications occurred more often with higher body weight (per 10 kg: OR = 1.4; 95% CI = 1.01-1.95; P = 0.04). Overall complication rate in diagnostic coronary angiography is very low and related to the experience of the performing cardiologist and catheter size. The only predicting risk factors for major complications in coronary angiography were catheter size and body weight.

Four French catheters for diagnostic coronary angiography

A randomized study was conducted to assess the feasibility of 4 Fr catheters for diagnostic coronary angiograms. A total of 1,114 consecutive patients were randomized to 4 or 5 Fr catheters. Ease of use of catheters was subjectively assessed by the primary operator and the picture quality was assessed by two independent observers with a good interobserver variability (r = 0.94; P < 0.001). Predischarge local complications were recorded by the attending physician. No statistically significant difference was observed in the picture quality for the left coronary artery, right coronary artery, aorta, left ventricle, venous grafts, or renal arteries between the two groups. Fluoroscopy time (7.1 +/- 5.6 for 4 Fr vs. 6.7 +/- 5.7 min for 5 Fr) and contrast quantity (140 +/- 58 vs. 144 +/- 57 ml) were comparable between the two groups. There was a statistically significant difference in favor of the 5 Fr group as regards maneuverability of catheters (93% vs. 79%; P < 0.001), and 5 Fr pigtail catheters crossed the aortic valve easier than the 4 Fr pigtail catheters (91% vs. 81%; P < 0.001). Crossover to the other catheter size or a larger sheath was more frequent with 4 Fr catheters (33/522 vs. 3/592; P < 0.001). Median time to hemostasis was 9 min for 4 Fr and 14 min for 5 Fr (P < 0.001). Of the 4 Fr patients, 84% could be mobilized at 1 hr and 86% of 5 Fr patients at 2 hr. Significant hematomas were observed in 2% with 4 Fr or 5 Fr and small hematomas in 10% and 16%, respectively (P = NS). Time to discharge was comparable in both groups (4.0 +/- 3.2 with 4 Fr vs. 4.3 +/- 3.7 hr with 5 Fr). The 4 Fr catheters are a good alternative for diagnostic coronary angiograms. The increased difficulty in maneuverability and a need for catheter changes in 70% are compensated for in part by easier hemostasis. With increasing use and finesse of these catheters, the difficulty in maneuverability are likely to be overcome.

[Coronary angiography with 4 f catheters by the radial: minimally invasive catheterization]

INTRODUCTION AND OBJECTIVES

Experience with 4 F catheters in cardiac catheterization is limited. These devices appear to be more suitable for the radial artery approach than conventional 6 F catheters.

METHODS

We analyze our preliminary experience with diagnostic catheterization of the radial artery with 4 F catheters. Angiographic images were evaluated using a predefined scale (1. poor; 2. acceptable; 3. optimal). In a subgroup of patients who underwent coronary angioplasty, the quantitative angiographic data obtained with the 4 F catheter were compared to those obtained with the 6 F guide catheter. In all cases the patients were clinically followed-up at 24 h and 7 days.

RESULTS

Two hundred and six studies performed over a 12-month period were reviewed. In 6 cases (2.9%) the femoral vein had to be used instead and in 4 cases (1.9%) the 4 F catheters were replaced by 6 F catheters. The left coronary angiography was graded as optimal in 83% and as acceptable in 15%. Right coronary artery images were considered optimal in 93% and acceptable in 7%. There was an excellent correlation between the reference diameter obtained by quantitative angiography with the 4 F catheter and values obtained with a 6 F guide catheter (r = 0.92; p < 0.01). No major vascular complications occurred.

CONCLUSION

4 F catheters are appropriate for systematic use in diagnostic procedures using the radial access.

Pseudoaneurysms

Vascular complications that are the result of invasive diagnostic or therapeutic procedures requiring arterial access occur frequently. A common complication, pseudoaneurysm, has significant risk of expansion, extrinsic compression on native arteries, rupture, embolization, and infection. A pseudoaneurysm represents a persistent defect in the walls of the artery, resulting in extravasation of blood outside of the artery. This extravascular blood is confined to the surrounding soft tissues. Clinical suspicion and duplex ultrasonography are the primary diagnostic modalities. There are several options for treatment of pseudoaneurysms, including surgical repair and ultrasound-guided compression. However, a new therapeutic option, ultrasound-guided thrombin injection, has become the treatment of choice for pseudoaneurysms. This procedure is highly effective, rapid, and very safe. Using direct, real-time visualization of the pseudoaneurysm, a needle is inserted percutaneously into the pseudoaneurysm sac, and a small amount of dilute bovine thrombin is injected. Thrombosis of the sac is rapidly evident. Rare complications include thromboembolism into the native artery and hypersensitivity reaction to bovine thrombin.

Multicentre, prospective, randomized trial of 4 vs. 6 French catheters in 410 patients undergoing coronary angiography

The aim of this study was to assess the quality of angiograms obtained using 4 Fr catheters compared with 6 Fr catheters, the ease of use of the 4 Fr catheters, and the safety of patient mobilization 1 hr following 4 Fr angiography. Details of catheter performance and procedural details were recorded at the time of the angiogram. The angiographic images were scored on the quality and completeness of vessel opacification throughout systole and diastole. A total of 410 patients were recruited. There was no difference between 4 and 6 Fr for procedural variables. All angiograms were considered to be of diagnostic quality. The angiographic scores for the right coronary artery and left ventricular injections were no different between 4 and 6 Fr. However, the angiographic scores for the left anterior descending and circumflex arteries were lower with 4 than with 6 Fr (both P < 0.05). Patients who had 4 Fr angiography mobilized safely at 1 hr and reported significantly less discomfort and bruising than 6 Fr patients. Good-quality diagnostic coronary angiograms can be achieved using 4 Fr catheters with the advantage of earlier postprocedural mobilization and reduced discomfort and bruising for the patient.

Randomized comparison of coronary angiography using 4F catheters: 4F manual versus "Acisted" power injection technique

Compared with 6F catheters, diagnostic coronary angiographic and ventriculographic images with 4F catheters can be obtained with equivalent results using less radiographic contrast volume. Whether 4F coronary angiography would be superior using a power-assisted, operator-controlled technique compared with manual technique is unknown. To determine whether 4F coronary angiography using operator-controlled power injection (Acist, Minneapolis, MN) was equivalent or superior to the 4F manual technique, 96 unselected patients undergoing transfemoral coronary angiography were randomized to 4F catheter using a power injection or manual technique. Procedural characteristics and angiographic quality scores were analyzed. Comparing the 4F manual with the 4F power-injection technique, coronary angiographic quality scores were equivalent (left coronary artery 4.7 +/- 0.5 vs. 4.7 +/- 0.6, P = 0.99; right coronary artery 4.94 +/- 0.2 vs. 4.88 +/- 0.1, P = 0.21). Left ventriculography scores were lower in 4F Acist with similar contrast volumes. The total study contrast volume was significantly less in the 4F Acist group (119 +/- 35 vs. 149 +/- 49 ml, P = 0.001). Compared with the 4F manual contrast injection technique, diagnostic angiography through 4F catheters with power contrast injection resulted in equivalent coronary angiographic image quality with significantly less radiographic contrast volume.

Coronary angiography using 4 Fr catheters with acisted power injection: A randomized comparison to 6 Fr manual technique and early ambulation

Coronary angiography using 4 Fr catheters may reduce access site complications, promote better utilization of outpatient facilities, but at a cost of suboptimal image quality. To determine whether 4 Fr diagnostic angiography with power injection (Acist, Minneapolis, MN) was equivalent to 6 Fr manual technique, 101 unselected patients were randomized to transfemoral coronary angiography with 4 or 6 Fr catheters. Procedural characteristics, angiographic quality scores, and results of 90 min ambulation were analyzed. Coronary angiographic quality scores using 4 Fr and 6 Fr catheters were equivalent (left coronary artery 4.73 +/- 0.6 vs. 4.80 +/- 0.65, P = 0.28; right coronary artery 4.98 +/- 90.13 vs. 4.97 +/- 0.16, P = 0.48). However, 4 Fr left ventriculographic image score was lower (4.53 +/- 0.68 vs. 4.83 +/- 0.42, P = 0.0002), attributed, in part, to a smaller injected contrast volume (32 +/- 11 vs. 37 +/- 4 mL, P = 0.001). The total study contrast volume was significantly less in the 4 Fr group (119 +/- 35 vs. 159 +/- 52 mL, P = 0.001). Complications related to early ambulation at 90 min were similar and minimal in both groups. Compared to 6 Fr manual contrast injection technique, diagnostic angiography through 4 Fr catheters with power contrast injection resulted in equivalent coronary angiographic image quality, slightly reduced but diagnostic left ventricular image quality, and significantly less contrast volume. Four Fr angiography facilitates early ambulation without compromising safety and image quality.

Five French (5 Fr) guiding catheters for percutaneous coronary angioplasty and stent placement: An initial feasibility study

Thirty patients were treated with percutaneous coronary intervention (PCI) using a 5 Fr guiding catheter. A recently developed, mechanically advantaged hand injector was used to deliver contrast and achieved excellent visualization through the 5 Fr system. Stent sizes ranged from 2.25 to 4.00 mm in diameter and from 8 to 24 mm in length. All primary lesions were successfully treated. The average contrast use was 70 cc per case. There were no major complications and only one minor femoral hematoma. In selected patients, a balloon angioplasty and stent placement can be performed safely and successfully with 5 Fr guiding catheters using currently available products. This technique creates a smaller arterial puncture site, which may obviate the need for a closure device and allow early and safe ambulation. With 5 Fr systems, it appears that contrast usage is reduced, thereby potentially decreasing cost and morbidity. Cathet. Cardiovasc. Intervent. 51:352-357, 2000.

Experience with Four French Catheters for Outpatient Coronary Angiography

Previous studies have demonstrated the efficacy and safety of outpatient cardiac catheterization on stable patients at low risk. We present our experience with four French catheters in 104 patients (72 male, 32 female, mean age 51 years old) with coronary angiography done as an outpatient procedure. No heparin was given during the procedure. After initial hemostasis had been attained, the patients returned to day center with vital signs monitored regularly. Patients were allowed ambulation after 4 hours' bed rest and were discharged the same afternoon. Normal coronary angiogram study was found in 76% of the study population. Single-vessel disease, double-vessel disease, triple-vessel disease, and left-main disease were found in 12%, 9.6%, 2%, and 1%, respectively. Nearly all of the patients demonstrated normal ventricular contraction (99%). Average procedural time was 20.2 +/- 4.4 minutes. Average hemostatic time was 8.4 +/- 3.1 minutes. No mortality directly attributed to the catheterization occurred in our study population. Moreover, there were no myocardial infarction, acute pulmonary edema, severe allergic reaction, and cerebrovascular accident. Femoral puncture site complication was only limited to superficial skin bruise. Quality of the cineangiogram was good in majority of the patients. Therefore, this study demonstrates that outpatient cardiac catheterization using four French Judkins catheter is a safe and cost-effective procedure.