Comparison of 4 and 6 French catheters for coronary angiography: real-world modeling

Femoral artery vascular complications are the most common adverse events following cardiac catheterization. Smaller diameter introducer sheaths and catheters are likely to lower the puncture site complication rate but may hinder visualization.

To evaluate the safety and angiographic quality of 4 French catheters.

The study was designed to simulate real-life operator-based experience. Diagnostic angiography was performed with either 4F or 6F diagnostic catheters; the size of the catheter used in each patient was predetermined by the day of the month. Patients undergoing 4F and 6F diagnostic angiography were ambulated after 4 and 6 hours, respectively. The following technical parameters were recorded by the operator: ease of introducer sheath insertion, ease of coronary intubation, ease of injection, coronary opacification, collateral flow demonstration, and overall assessment. Adverse events were recorded in all patients and included minor bleeding, major bleeding (necessitating blood transfusion), minor hematoma, major hematoma, pseudo-aneurysm formation and arteriovenous fistula.

The study group included 177 patients, of whom 91 were in the 4F arm and 86 in the 6F arm. Demographic and procedural data were similar in both groups. Seventy-seven percent of 6F and 50% of 4F procedures were evaluated as excellent (P < 0.05). This difference was attributed to easier intubation of the coronary ostium and contrast material injection, increased opacification of the coronary arteries, and demonstration of collateral flow with 6F catheters. Complications occurred in 22% of patients treated with 6F catheters and in 10% of those treated with 4F catheters (P = 0.11). Of the 50 patients who switched from 4F to 6F 12% had complications. In patients undergoing diagnostic angiography, the complication rate was 10% vs. 27% (most of them minor) in the 4F and 6F groups, respectively (P < 0.05).

Patients catheterized with 4F have fewer complications compared with 6F diagnostic catheters even when ambulated earlier. Although 4F had a reduced quality compared to 6F angiographies, they were evaluated as satisfactory or excellent in quality 85% of the time. 4F catheters have a potential for reduced hospitalization stay and are a good option for primary catheterization in patients not anticipated to undergo coronary intervention.