Tugrul Norgaz

The effect of acetylsalicylic acid resistance on prognosis of patients who have developed acute coronary syndrome during acetylsalicylic acid therapy

AIM The relationships between clinical events and acetylsalicylic acid resistance (AR), as well as its frequency, have been established in stable patients with coronary artery disease (CAD). Although acute coronary syndrome (ACS) patients taking acetylsalicylic acid have been accepted as a high-risk population, the role of AR has not been investigated in these patient groups. Thus, in the present study, the impact of AR was investigated in patients with ACS who were taking acetylsalicylic acid. METHODS Between January 2001 and February 2003, 140 ACS patients were included in the present prospective study. All patients had ACS while taking acetylsalicylic acid. Coronary angiographic scores for severity and extent of CAD were determined for all patients. The effect of acetylsalicylic acid on platelet function was assessed by the platelet function analyzer PFA-100 (Dade Behring, USA). The primary end point was the composite of death, myocardial infarction, cerebrovascular accident and revascularization. The mean follow-up period was 20 months. RESULTS Patients with AR were older than patients without AR (63.8+/-10.8 years versus 58.3+/-11.2 years; P=0.005). Moreover, myocardial damage was higher in patients with AR according to cardiac troponin T values (1.11+/-1.3 mug/L versus 0.41+/-0.5 mug/L; P=0.01). The composite end point of death, myocardial infarction, cerebrovascular accident or revascularization was present in 16 of 45 patients (35%) with AR and in 13 of 79 patients (16%) without AR (hazard ratio 2.46, 95% CI 1.18 to 5.13; P=0.016). After adjustment for age, platelet count, cardiac troponin T value and CAD severity score, AR remained an independent predictor for long-term adverse events (hazard ratio 3.03, 95% CI 1.06 to 8.62; P=0.038). CONCLUSIONS The clinical event rate was found to be higher in ACS patients with AR than in those without AR. Thus, it may be concluded that there is a strong correlation between a worse prognosis and AR in these patients.

Congenital coronary anomalies in adults: Comparison of anatomic course visualization by catheter angiography and electron beam CT

The objective of this study was to compare the anatomic course of anomalous coronary arteries by axial and three‐dimensional volume‐rendered electron beam computed tomography (EBCT) angiography and X‐ray catheter angiography (CAG). We performed a blinded study where patients who previously underwent CAG with (n = 14) and without (n = 14; age‐ and gender‐matched controls) anomalous coronary anatomy were studied with EBCT coronary angiography. Forty to 50 EKG‐triggered 3 mm overlapping axial slices were acquired with 2 mm table movement within one breath hold during the i.v. injection of 140 cc of nonionic iodinated contrast (4 ml/sec). The axial source images and volume‐rendered three‐dimensional reconstructions were evaluated for the presence, type, and course of coronary anomalies and the results were compared to those of CAG. All normal and anomalous coronary arteries were identified by both modalities in all subjects. Identified anomalies include single coronary artery (n = 3), left‐sided right coronary artery (n = 3), right‐sided left main coronary artery (n = 3), anterior descending coronary artery (n = 2), circumflex coronary artery (n = 2), and separate left‐sided ostia for left anterior descending and circumflex coronary arteries (n = 1). In five cases, there was discrepancy in the course of the anomalous vessels between the two modalities. Consensus reading among cardiologist and radiologists favored the interpretation of EBCT over catheter angiography. Noninvasive EBCT coronary angiography compares well with CAG in identifying anomalous coronary arteries and may provide confirmatory evaluation of their precise anatomic relationships to the heart and great vessels.

A randomized study comparing the effectiveness of right and left radial approach for coronary angiography

Our aim was to compare the effectiveness between right radial approach (RRA) and left radial approach (LRA) by means of a randomized study in a large unselected patient population undergoing diagnostic coronary angiography.

The outcome of primary percutaneous coronary intervention for stent thrombosis causing ST-elevation myocardial infarction.

BACKGROUND There are very few scientific data about the effectiveness of primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) due to stent thrombosis (ST). The purpose of the present study is to investigate the efficacy and outcome of primary PCI for STEMI due to ST in the largest consecutive patient population with ST reported to date. METHODS A total of 2,644 consecutive STEMI patients undergoing primary PCI were retrospectively enrolled into the present study. The primary end point of this study was successful angiographic reperfusion defined as postprocedural Thrombolysis In Myocardial Infarction grade III flow. The secondary end points were cardiovascular death and reinfarction. RESULTS Stent thrombosis was the cause of STEMI in 118 patients (4.4%). In patients with ST, angiographic success (postprocedural Thrombolysis In Myocardial Infarction grade III flow) was worse than in patients with de novo STEMI (76.3% vs 84.8%, P = .01). Patients with ST had significantly higher incidence of in-hospital cardiovascular mortality than patients with de novo STEMI (10.2% vs 5.3%, P = .02). In-hospital reinfarction rate was similar in both groups. In addition, long-term (mean 22 months) cardiovascular mortality and reinfarction rates were significantly higher in patients with ST compared with those without (17.4% vs 10.5%, P = .02 and 15.6% vs 9.5%, P = .03, respectively). CONCLUSIONS Primary PCI for treatment of ST is less effective, and these patients are at increased risk for in-hospital and long-term mortality compared with patients undergoing primary PCI due to de novo STEMI.

The relationship between preprocedural platelet size and subsequent in-stent restenosis.

Objective — Elevated mean platelet volume predicts restenosis after percutaneous transluminal coronary angioplasty but its effect on the development of in-stent restenosis is not known. We assessed the effect of mean platelet volume measured before coronary stent implantation for stable angina pectoris on subsequent development of in-stent restenosis. Methods and results — We retrospectively analysed the data of 60 patients who had stent implantation on one native coronary artery for stable angina pectoris and control angiographies for clinically suspected restenosis within 6 months. Mean platelet volume was measured by auto analyzer one day before stent implantation. Clinical and demographic data and laboratory results were obtained from the hospital charts of the patients. In-stent restenosis was evaluated visually from control angiograms.Angiographic in-stent restenosis was present in 35 (58%) of 60 patients and 25 (42%) patients had no restenosis. Mean platelet volume in the in-stent restenosis group was 8.28 ± 0.71 fl compared to 7.63 ± 0.74 fl in the no-restenosis group (p = 0.001).There was a positive correlation between preprocedural mean platelet volume and development of in-stent restenosis (r = 0.44; p < 0.001). A mean platelet volume value of ≥ 8.4 fl was associated with an odds ratio of 16.0 for development of in-stent restenosis, with high specificity and positive predictivity but poor sensitivity and negative predictivity (96%, 93%, 40% and 53%, respectively). Conclusions — Mean platelet volume measured before stent implantation is correlated with subsequent development of in-stent restenosis. If preprocedural mean platelet volume is greater than 8.4 fl, in-stent restenosis is more probable to occur.

Comparison of outcomes in young versus nonyoung patients with ST elevation myocardial infarction treated by primary angioplasty.

ObjectivesWe sought to determine in-hospital and intermediate-term outcomes of primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI) in young adults. MethodsWe reviewed 2424 consecutive patients treated with primary angioplasty for acute MI; 465 were aged 45 or less (young group) and 1959 were 46–74 years of age (nonyoung group). Clinical characteristics, in-hospital and intermediate-term outcomes of primary PCI were analyzed. ResultsCompared with nonyoung patients, the young patients had significantly lower in-hospital and intermediate-term mortality (for in-hospital mortaliy: 5.4 vs. 1.2%, P<0.001; for intermediate-term mortality: 5 vs. 1.3%, P<0.001). By multivariate Cox regression analysis in all 2424 patients; cardiogenic shock, diabetes mellitus, anterior MI and unsuccessful procedure were independent predictors of both in-hospital and intermediate-term mortality whereas age [odds ratio (OR): 1.07, P<0.001], female sex (OR: 1.88, P = 0.04), MI history (OR: 3.05, P = 0.001) and multivessel disease (OR: 2.15, P = 0.01) were independent predictors of only intermediate-term mortality. The young group had lower unsuccessful procedure rates of primary PCI for STEMI (4.9 vs. 10.1%, P = 0.001). ConclusionThese results suggest that young adults who underwent primary PCI have favorable in-hospital and intermediate-term outcomes. Moreover, primary PCI for young adults with STEMI is safer, more feasible and effective than for a relatively older population.

Significance of mean platelet volume on prognosis of patients with and without aspirin resistance in settings of non-ST-segment elevated acute coronary syndromes

Platelet volume is a marker of platelet function and activation. An elevated mean platelet volume (MPV) is associated with acute coronary syndromes (ACS). Recurrent cardiovascular events were found to be higher in patients with aspirin resistance. In this study, we investigated the effect of MPV on prognosis of patients with and without aspirin resistance by PFA-100 in settings of non-ST-segment elevated ACS. Two hundred and twenty patients with ACS were followed for an average of 14.86 ± 5.93 months for the occurrence of death, myocardial infarction (MI) and revascularization. Aspirin effect on platelet function was assessed by PFA-100. According to MPV value and aspirin resistance status, patients were divided into four groups. Group 4 (with an elevated MPV and aspirin resistance) was significantly associated with worse prognosis for composite endpoint (death, MI and revascularization), death and MI (for all, log–rank P < 0.0001). Multivariate analysis showed that presence of an elevated MPV and aspirin resistance was an independent predictor of composite endpoint [hazard ratio 8.21, 95% confidence interval (CI) 3.48–19.35, P < 0.0001], death (hazard ratio 5.48, 95% CI 1.62–18.53, P = 0.006) and MI (hazard ratio 4.44, 95% CI 1.57–12.58, P = 0.005). Presence of an elevated MPV and aspirin resistance was significantly associated with death, MI and the composite endpoint, due to the lack of beneficial effect of aspirin on activated platelets. Patients with ACS, especially in the presence of an elevated MPV may benefit from the evaluation of aspirin resistance for risk stratification.

The long-term incidence and predictors of radial artery occlusion following a transradial coronary procedure.

BACKGROUND Radial artery occlusion (RAO) is an infrequent complication of transradial coronary procedures (TRA). To our knowledge, there is no satisfactory data regarding the late term incidence and predictors of RAO in the literature. Our aim was to establish the long-term incidence of radial artery occlusion and investigate its predictors. METHODS This was a single center prospective study. A total number of 409 consecutive patients undergoing their first TRA were recruited. Clinical and procedural data were all recorded. Doppler ultrasound examination was performed at 6-15 months following the intervention. RESULTS RAO was detected in 67 patients and 342 patients maintained radial artery patency. The overall RAO incidence was 16.4% at late term. Patients with RAO were younger than the patients with patent radial arteries (55.9 ± 9.7 vs. 59.1 ± 9.4 years, p = 0.014). The incidence of RAO in hypertensive patients (9.8%) was lower (p < 0.001) than the observed incidence (23%) in non-hypertensive patients. RAO group had higher rate (28%, p = 0.027) of post--procedural access site pain. Regression analysis revealed that hypertension was negative while post-procedural access site pain was positive independent predictors for RAO. In addition, the relative risk for RAO also increased significantly (p < 0.001) when the ratio of sheath/artery diameter (S/A) was > 1. CONCLUSIONS The present study reveals that the long-term incidence of RAO is 16.4%. Hypertension, post-procedural access site pain and S/A ratio > 1 are independent predictors of RAO at late term.

Comparison of Effects of Low- versus High-Dose Heparin on Access-Site Complications during Transradial Coronary Angiography: A Double-Blind Randomized Study

Objectives: Although heparin is highly effective in reducing the rate of radial artery occlusion after transradial catheterization, the optimal heparin dose is still controversial. The aim of this study was to evaluate the efficacy and safety of two different heparin doses during transradial coronary angiography. Methods: 490 consecutive patients undergoing transradial coronary angiography were prospectively enrolled into this double-blind randomized trial. A total of 202 patients enrolled in the low-dose (LD; 2,500 U of heparin) group and 202 patients enrolled in the high-dose (HD; 5,000 U of heparin) group were included in the final analysis. The primary endpoint of the study was radial artery occlusion. Bleeding and hematomas were the secondary outcome measures. Results: At day 7, radial artery occlusion occurred in 5.9% of the patients in the LD group and in 5.4% of the patients in the HD group (p = 0.83). Bleeding during deflation of the transradial band occurred in 6.4% of the patients in the LD group and in 18.3% of the patients in the HD group; the difference was statistically significant (p < 0.001). Higher-dose heparin was found to be an independent predictor of bleeding (p = 0.007). Conclusion: A lower dose of heparin (i.e. 2,500 U) decreases bleeding during transradial band deflation without an increase in radial artery occlusion.

Incidence and Predictors of Radial Artery Spasm at the Beginning of a Transradial Coronary Procedure

OBJECTIVES Our aim was to establish the frequency of radial artery spasm (RAS) and its predictors at the beginning of a transradial approach (TRA). METHODS This was a single-center prospective study. A total of 1,722 consecutive patients undergoing their first transradial coronary procedure were recruited. After radial artery puncture, a hydrophilic sheath was used to complete arterial puncture, then 500 μg glycerol trinitrate and 2.5 mg verapamil were injected into radial artery along the sheath. After retrograde radial arteriography spasm was defined angiographically as a stenosis greater than 25%. Patient demographics, procedural data such as total procedural duration, the number of catheters and guidewires used, the amount of contrast media usage, dose area product (DAP) and fluoroscopy time, and vascular complications were recorded. RESULTS The overall spasm incidence was 10.3%. The procedural success rate was lower in patients with spasm than in patients without spasm (80% vs. 95.7%, P < 0.001). The patients with spasm were older (mean age 63.9 ± 9.4 years vs. 60.0 ± 11.2 years, P < 0.001) and more commonly female (51.3% vs. 34.4%, P < 0.001). Spasm was more common in hypertensive patients (66% vs. 56%, P < 0.009). Surprisingly, smoking was less common in patients with spasm (17% vs. 29%, P < 0.001). Multiple logistic regression analysis showed that female gender (OR = 1,524, 95% CI: 1.033-2.248, P = 0.034) was the only independent predictor of RAS at the beginning of the procedure. CONCLUSIONS The incidence of RAS was 10,3%, and female gender was the sole independent predictor of RAS at the very beginning of the procedure in patients undergoing a TRA.