Application of a rapid exchange extension catheter technique in type B2/C nonocclusive coronary intervention via a transradial approach

Table 1 Patients’ clinical characteristics

Clinical characteristic	n	%
Mean age (yr)	62.8 ± 9.5
Male	104	77.0
Female	31	23.0
BMI (m/kg2)	26.2 ± 2.9
Creatinine/(μmol/L)
Previous	77.5 ± 27.2
Postoperation	82.8 ± 30.1
Risk factors
Hypertension	102	75.6
Diabetes mellitus	59	43.7
Hypercholesterolemia	14	10.4
Angiography indication
Unstable angina	94	69.6
STEMI	25	18.5
NSETMI	16	11.9

BMI: Body mass index; STEMI: ST-segment elevation myocardial infarction; NSETMI: Non-ST-segment elevation myocardial infarction.

Table 2 Lesion position and selection of guide catheter

Target vessel	n (%)	Type of GC	n (%)
RCA	58 (43.0)	JR	52 (38.5)
		SAL	6 (4.4)
LAD	45 (33.3)	JL	9 (6.7)
		EBU	36 (26.7)
LCX	32 (23.7)	JL	5 (3.7)
		EBU	27 (20.0)

GC: Guide catheter; RCA: Right coronary artery; LAD: Left anterior descending artery; LCX: Left circumflex artery.

Table 3 Summary of procedural characteristics

Procedural characteristic	n (%) or mean ± SD
Procedural results
Technique success	128 (94.8)
PCI success	125 (92.6)
Stent implantation	124 (91.9)
DCB therapy	1 (0.7)
Artery path
Right radial artery	128 (94.8)
Left radial artery	5 (3.7)
Distal radial artery	2 (1.5)
Indication for using a rapid exchange extension catheter
Difficult balloon delivery	35 (25.9)
Difficult stent delivery	96 (71.1)
Difficult posterior expansion balloon	4 (3.0)
Preprocess lesion before delivering the rapid exchange catheter
Multiple predilatation	77 (57.0)
Buddy wire technique	45 (33.4)
Balloon anchoring technique	8 (5.9)
Cutting balloon modification	5 (3.7)
Depth of extension catheter intubation (mm)	25.3 ± 15.4
Rapid exchange catheter service time1 (min)	18.9 ± 9.7
PCI operation time2 (min)	35.8 ± 16.6
Mean length of stents (mm)	33.5 ± 14.4
Mean diameter of stents (mm)	2.75 ± 0.45
Length of DCB (mm)	30.0
Diameter of DCB (mm)	3.0
Contrast dose (mL)	162.2 ± 38.3
Perioperative dual antiplatelet
Aspirin + clopidogrel	77 (57.0)
Aspirin + ticagrelor	58 (43.0)
Perioperative anticoagulant
Unfractionated heparin	98 (72.6)
Bivalirudin	37 (27.4)

¹The time from rapid exchange extension catheter entering the coronary artery to returning to the guide catheter after stent implantation. ²The time from the guide catheter entering the coronary artery opening to the end of the operation. PCI: Percutaneous coronary intervention; DCB: Drug-coated balloon.

Table 4 Adverse events and major adverse cardiovascular events

Adverse event	n (%)
Intraoperative complication
Perforation	0
Dissection	9 (6.7)
Thrombosis	0
Air embolism	0
Pressure damping	27 (20.0)
Stent deformation or stripping	6 (4.4)
Extension catheter fracture	0
Perioperative complication
Bleeding	5 (3.7)
Major bleeding	0
Stent thrombosis	0
MACEs during hospitalization
Recurrence of myocardial infarction	0
Repeated revascularization	0
All-cause death	0
MACEs in the one-month follow-up
Recurrence of myocardial infarction	0
Repeated revascularization	0
All-cause death	0

MACEs: Major adverse cardiovascular events.