Magnesium sulphate during transradial cardiac catheterization: a new use for an old drug?

OBJECTIVE: To assess the effect of intra-arterial magnesium on the radial artery during transradial cardiac catheterization. BACKGROUND: Transradial coronary angiography has become popular in the last decade and offers several advantages over transfemoral angiography. Radial artery spasm is a major limitation of this approach, and a vasodilatory cocktail is usually given. The aim of this study was to examine the effect of magnesium sulphate on the radial artery during cardiac catheterization. METHODS: This was a prospective, double-blind, randomized trial of 86 patients undergoing radial catheterization. Patients were randomized to receive magnesium sulphate (150 mg) or verapamil (1 mg) into the radial sheath. Radial dimensions were assessed using Doppler ultrasound. The primary endpoint of the study was a change in radial artery diameter following administration. Secondary endpoints included operator-defined radial artery spasm and patient pain. RESULTS: Following administration of the study drug, there was an increase in radial artery diameter in both groups (p < 0.01), although the increase seen was greater in the group receiving magnesium (magnesium 0.36 +/- 0.03 mm; verapamil 0.27 +/- 0.03 mm; p < 0.05). Administration of verapamil resulted in a fall in mean arterial pressure (MAP) (change in MAP -6.6 +/- 1.4 mmHg; p < 0.01), whereas magnesium did not have a hemodynamic effect. Severe arm pain (pain score > 5) was observed in 14 (30%) patients receiving verapamil and 9 (27%) receiving magnesium (p = NS). CONCLUSION: This study demonstrates that magnesium is a more effective vasodilator when compared to verapamil, with a reduced hemodynamic effect, and is equally effective at preventing radial artery spasm. As such, the use of this agent offers distinct advantages over verapamil during radial catheterization.

Safety of same day discharge radial PCI in patients under and over 75 years of age.

To check the safety of same day discharge radial PCI in patients under or over 75 years of age. A total of 943 patients who had same day discharge radial PCI between April 1998 and March 2001 were contacted. Patient health status, entry site complications, and repeat interventions during the first month after the procedure were compared in patients under 75 years of age (< 75) with those 75 or over (> or = 75). Responses were received from 811 patients (694 aged < 75 and 117 aged > or = 75 years). Two hundred and thirty-eight patients (34.3%) aged < 75 years and 36 patients (30.7%) aged > or = 75years reported one or more access site complications during the first 24 hours postdischarge, and 105 (15.1%) and 12 patients (10.3%), respectively, during the first month, (P > 0.05). However, all complications in both groups were minor and none of the patients required admission to the hospital. During the first 24 hours postdischarge only one patient (0.1%) aged < 75 years had a repeat angiogram showing a normal patent vessel, while during the first month 4 patients (0.6%) aged < 75 years and none aged > or = 75 years had target vessel closure. Out of the 132 patients who did not respond to our questionnaire, 1 patient aged < 75 and 1 patient aged > or = 75 years had subacute stent thrombosis within a month and died. There were no major entry site complications, and target vessel closure (0.6% versus 0.7%) was similar in patients aged < 75 and > or = 75 years. Thus, same day discharge radial PCI is safe in patients 75 years old or over.

Day procedure intervention is safe and complication free in higher risk patients undergoing transradial angioplasty and stenting. The discharge study.

OBJECTIVES: To assess the timeframe of postprocedural complications following transradial percutaneous intervention in selected nonlow-risk risk patients as a feasibility study for same day discharge. BACKGROUND: Percutaneous coronary intervention (PCI) is traditionally performed as an inpatient procedure. Transradial access with its lower complication rate facilitates safe and same day discharge. We hypothesize that with current standards of pharmacotherapy and intervention, complications post transradial percutaneous coronary angioplasty even in a nonlow-risk patient cohort will be evident within 6 hr or occur more than 24 hr post procedure. Under these circumstances, overnight stay results in no improvement in patient safety. METHODS: 2,189 patients underwent transradial PCI at our institution between January 2005 and June 2006. Of these 1,174 were assessed as intermediate or high risk and admitted postprocedure. The remaining 1,015 were assessed as low risk and discharged the day of procedure. All 1,174 inpatients were entered into our study database. Information was collected on patient demographics, angiographic characteristics, post procedural complications, and timing of post procedural events. RESULTS: 1,543 ACC type B2 or C lesions were treated in 1,174 patients. All post-procedural complications were identified within 6 hr of the intervention or occurred more than 24 hr later when patients would have been discharged according to overnight admission protocols. CONCLUSIONS: Day case transradial percutaneous intervention with a 6-hr period of post procedure observation is a safe and feasible practice. The presence of higher-risk features should not be considered an absolute indication for overnight admission in patients considered clinically appropriate for discharge.

Vascular communications of the hand in patients being considered for transradial coronary angiography: is the Allen's test accurate?

OBJECTIVES: The purpose of this study was to assess the accuracy of the Allen's test (AT) in predicting hand ischemia in patients undergoing transradial coronary angiography. BACKGROUND: Patients with poor vascular communications between the radial artery (RA) and ulnar artery (UA), as indicated by an abnormal AT, are usually excluded from transradial coronary angiography to avoid ischemic hand complications. METHODS: Over a four-month period, patients undergoing coronary angiography were screened for AT time. Circulation in the RA, UA, principal artery of the thumb (PAT), and thumb capillary lactate were measured before and after 30 min of RA occlusion. RESULTS: Fifty-five patients were studied (20 normal, 15 intermediate, 20 abnormal). Three patients with an abnormal AT were excluded, owing to absence of detectible flow in the distal UA. Patients with an abnormal AT were all men, had a larger RA (3.4 vs. 2.8 mm; p <0.001), and smaller UA (1.9 vs. 2.5 mm; p <0.001), compared with patients with a normal AT. After 30 min of RA occlusion in patients with abnormal AT, blood flow to the PAT improved (3.2 to 7.7 cm/s; p <0.001) yet remained reduced relative to patients with normal AT (7.7 vs. 21.4 cm/s; p <0.001. Thumb capillary lactate was elevated in patients with an abnormal AT (2.0 vs. 1.5 mmol/l; p = 0.019). CONCLUSIONS: After 30 min of RA occlusion, patients with an abnormal AT showed significantly reduced blood flow to the thumb and increased thumb capillary lactate (compared with patients with a normal AT) suggestive of ischemia. Transradial cardiac catheterization should not be performed in patients with an abnormal AT.

A comparison of the radial and the femoral approach in vein graft PCI. A retrospective study.

BACKGROUND: Transradial PCI is a safe and effective method of percutaneous revascularization. However, there is limited data on the efficacy of the transradial approach for saphenous vein graft (SVG) PCI. METHODS: We studied 334 patients who underwent SVG PCI between January 2000 and December 2003, and compared the radial (132 patients) and the femoral (202 patients) approach. RESULTS: Mean EF (55.6+/-18.6% radial versus 58.1+/-16.8% femoral), lesion location (proximal, mid, distal: 22.6/50.6/26.7% versus 22.6/44.5/32.9% respectively) and lesion type (B1/B2/C: 3.4/4.1/92.5% versus 0.4/3.1/96.5%) were similar in both groups (P>0.05). Five patients had a failed radial attempt (3.8%) and were switched to the femoral approach. Mean fluoroscopy time (20.4+/-12.2 versus 18.4+/-10.2 min), procedural time (60.0+/-27.2 versus 61.6+/-24.9 min) and the use of contrast (223+/-91 versus 234+/-91 ml) IIB/IIIA inhibitors (27.2 versus 33.2%), and stenting (81.5 versus 81.3%) were similar in both groups, whereas 5 or 6 French sheaths were used more often in the radial group (83.4 versus 64.9%, P<0.01). Angiographic success (93.9 versus 92.9%), in hospital MACE (radial:5 MI (3.8%) versus femoral: 1 death (0.5%) and 7 MI (3.5%) and major vascular complications (0.7 versus 0.5%) were also similar. CONCLUSIONS: The radial approach in SVG PCI is as fast and successful as the femoral.