Decrease in coronary flow after consecutive injections of contrast media during coronary angiography.

BACKGROUND: TIMI frame count (TIMIfc) is widely used to assess coronary flow during angiography and there are studies showing the effects of contrast media on blood cells. In this study, we investigate changes in coronary flow and in red blood cells following contrast injections. METHODS AND RESULTS: Coronary flow was assessed by TIMIfc in the left anterior descending and circumflex coronary arteries of patients undergoing elective angiography. Changes in the morphology of red blood cells and in the mean corpuscular volume (MCV) were evaluated by optical microscopy. We enrolled 24 patients with a mean age of 61.9 ± 12 years. In 45 coronary arteries, the mean baseline-corrected TIMIfc was 19.4 ± 3.46 frames and the final one was 24.3 ± 3.2 frames (P=.001) with a mean increase of 4.92 ± 0.25 frames (frame range, 0-10), indicating significant impairment of coronary flow. There was an increase in the number of crenated red cells per camp (4.3 ± 3.4%; P=.001). The MCV changed from 86.6 ± 4.7 fL to 86.8 ± 4.6 fL (P=.011). There was no association of the TIMIfc increase with changes in either crenated red cells (P=NS) or MCV (P=NS). CONCLUSION: There was significant impairment of coronary artery flow following contrast injections during angiography. These findings indicate that the TIMIfc is affected by the timing of assessment during angiography, with implications for clinical trial design and for the use of TIMIfc as a surrogate endpoint. In addition, this impairment of coronary flow may have implications for slow flow observed during coronary interventions.

Impact of chronic kidney disease on the efficacy of drug-eluting stents: long-term follow-up study.

BACKGROUND: Patients with chronic kidney disease (CKD) submitted to coronary angioplasty have higher rates of target lesion revascularization (TLR) and mortality. Drug-eluting stents (DES) are associated with a lower rate of restenosis, compared to bare metal stents (BMS), although data on DES efficacy and safety is limited in patients with CKD. OBJECTIVE: We sought to evaluate the safety and efficacy of DES in patients with significant CKD as compared to patients without normal renal function in a real world registry. METHODS: 504 patients who underwent percutaneous coronary intervention with DES in two centers were included. Outcomes were stratified based on the presence of CKD, defined as a baseline glomerular filtration rate (GFR) < 60 ml/min/1.73 m². RESULTS: The mean follow-up was 22.7 months. CKD was present in 165 patients (32.7%). Patients with CKD were older, had a higher incidence of hypertension and diabetes. CKD patients presented an increased incidence of death (12.3% vs 2.4%, p < 0.001) and myocardial infarction (MI) (7.4% vs 3.3%, p = 0.04) compared to patients without CKD. TLR rates were similar between groups (4.8% vs 5.6%, p = 0.7, CKD and no CKD patients, respectively). Independent predictors of death were CKD (HR 6.93; 2.4 - 19.5, p < 0.001), current smoking (HR 3.66; 1.20 - 11.10, p = 0.02) and diabetes (HR 2.66; 1.03 - 6.60, p = 0.045). CONCLUSION: In this registry, coronary intervention with DES in patients with CKD was associated with similar TLR compared to patients without CKD, demonstrating the efficacy of DES in preventing in-stent restenosis in this patient population. CKD was related to significantly increased MI and mortality rates.