The impact of different techniques used for coronary angiography and percutaneous coronary intervention on the occurrence of procedure-related ischemic cerebral complications

Abstract: Background Coronary angiography (CA) is the gold standard in diagnosing and determining the treatment of patients with coronary heart disease. Procedure-related neurological complications are rare; 0.1-0.4% for CA and percutaneous coronary intervention (PCI). In contrast, the incidence of procedure-related silent cerebral lesions, shown with diffusion-weighted magnetic resonance tomography, is considerably higher (2-35%). Cerebral microemboli have been observed during different vascular procedures and are related to new silent cerebral lesions but their clinical impact is debated. CA and PCI can be performed with different techniques, i.e. with the radial or the femoral access. As procedure-related stroke is associated with high mortality, considerable morbidity and suffering it is important to study which technique entails the lowest risk for patient injury. Methods and results Study I: Fifty-one patients with stable angina pectoris were randomised to CA with the radial or the femoral access and the number of cerebral microemboli was assessed with bilateral transcranial Doppler technique of the middle cerebral arteries (MCAs). The number of particulate cerebral microemboli was signifiantly higher with the radial compared to the femoral access. The number of cerebral microemboli was higher for both access sites during catheter exchanges compared with other specifi procedural steps during CA, with most cerebral microemboli detected in the right MCA in the radial group. This indicates a causal anatomical link, as the catheter is advanced from the right radial artery through the brachiocephalic trunk before it bends into the ascending aorta to reach the coronary ostia. Study II: Forty-one patients with stable angina pectoris or non-ST-segment-elevation myocardial infarction scheduled for CA were randomised to two different guidewire techniques with the femoral access involving catheter advancement with or without a leading guidewire over the aortic arch. After the CA was completed, including contrast injections, the opposite technique was used on the same patient without further contrast injections. At the same time, the number of cerebral microemboli was registered using bilateral transcranial Doppler technique. The number of cerebral microemboli was higher when the catheter was advanced with, rather than without a leading guidewire over the aortic arch, independent of whether a complete CA was performed or if a catheter was placed in the vicinity of the coronary ostia only. Study III: All CAs and PCIs reported between 2003 and 2011, n= 336,836, to the Swedish Coronary Angiography and Angioplasty Register with information on access site were retrospectively analysed regarding the association between access site and procedure-related stroke or transient ischemic attack (TIA). After cross-checking the reported neurological complications with the corresponding medical records the incidence of procedure-related stroke or TIA was 0.16%. After multivariable adjustment, the radial access was associated with a higher risk for procedure-related stroke or TIA (risk ratio 1.30, 95% confience interval 1.04-1.62) compared with the femoral access. Parallel to the increased use of the radial access over time, the risk for procedure-related stroke or TIA also increased, although there was no signifiant interaction between the different time intervals observed. Study IV: Ninety-three patients with suspected or stable angina pectoris scheduled for CA or PCI were tested with Montreal Cognitive Assessment (MoCA) before and twice after the coronary procedure to study postprocedural cognitive impairment. A subgroup was monitored with bilateral transcranial Doppler technique to explore the relationship between cerebral microemboli and cognitive function. The patients were also randomised to radial or femoral vascular access site to study if the access site used was related to postprocedural cognitive impairment. Cognitive function assessed with the MoCA test was not impaired after the coronary procedure. There was no signifiant correlation between the results of the MoCA test and cerebral microemboli or vascular access site. Conclusions The choice of access site and guidewire technique used for CA and PCI had an impact on the occurrence of cerebral microemboli. There may be an association between the radial access and increased risk for procedure-related stroke or TIA, which should be studied further. Earlier studies have shown that cerebral microemboli are related to new silent cerebral lesions, but we found no cognitive impairment after coronary procedures using the MoCA test. Further studies are needed to explore the clinical impact of cerebral microemboli and to minimise or prevent the occurrence of procedure-related ischemic cerebral lesions in patients undergoing CA and PCI.