Ahmet Duran Demir

Imaging of coronary artery anomalies: the role of multidetector computed tomography.

BackgroundCoronary artery anomalies are evaluated by using catheter-based angiography. Multidetector row-computed tomography (MDCT) is a new noninvasive imaging technique that has excellent spatial resolution for detecting the origin and course of a coronary anomalous vessel. ObjectiveTo determine the sensitivity of multidetector computed tomography in patients who had coronary artery anomaly demonstrated by conventional coronary angiography. Material and methodsA retrospective evaluation to identify 23 patients, who underwent retrospective electrocardiographic (ECG)-gated MDCT, was done and in whom an anomalous coronary vessel was found at a single center. Metoprolol (50–100 mg) was given orally to all patients to reduce heart rate so as to get high-quality MDCT images. After performing MDCT, the CT scans of each patient were analysed and compared with their coronary angiograms by two experienced radiologists and one cardiologist who were unaware about the study, and the sensitivity of MDCT was determined. ResultsTwenty-three patients (age range 28–73) with seven different coronary arteries of the anomalous type were evaluated. Nineteen patients had an anomalous left coronary artery; three patients had an anomalous single coronary artery; and one patient had an anomalous right coronary artery. The most common anomaly type was the left circumflex coronary artery (52%). The origin and course of all anomalous vessels were detected by ECG-gated MDCT (Lightspeed 16, GE Medical Systems, Milwaukee, Wisconsin, USA). The sensitivity of 100% of MDCT was detected in patients who had anomalous coronary vessels. ConclusionWe suggest that MDCT could be a non-invasive alternative imaging technique to conventional coronary angiography for screening the anomalous vessels of coronary arteries because of its excellent spatial resolution, which is very important for detecting the relationship of anomalous vessels with great arteries and cardiac structures.

QT Dispersion in Single Coronary Artery Disease: Is There a Relation Between QT Dispersion and Diseased Coronary Artery or Lesion Localization?

It has been shown that QT dispersion (QTD) increases during episodes of myocardial ischemia or infarction. However, no extensive data on the relation between the diseased coronary artery or the localization of stenosis and the QTD are available. The aim of the study was to examine the relation between QTD and diseased coronary artery and lesion localization during exercise stress test in patients with single coronary artery disease without prior myocardial infarction. One hundred nineteen patients with single coronary artery disease and 53 patients with normal coronary arteries were enrolled in study. All patients underwent exercise stress test with modified Bruce protocol, and QT interval parameters were measured at rest and at minute 2 of the recovery (rec-2) period. QT dispersion at rest was found higher in all single-vessel disease groups compared with that in the control group, and corrected QT dispersion at rec-2 period was also markedly higher in left anterior descending, circumflex, and right coronary artery groups compared with that in the control group. No relation was found between QT dispersion and diseased coronary artery or the lesion localization. In conclusion, no qualitative difference was found between QT dispersion and diseased coronary artery or proximal or distal lesion localization. However, it was observed that patients with single-vessel disease had wider baseline QT dispersion as compared with that in the control group, which further increased significantly with exercise. This finding supports the idea that severity of localized ischemia rather than extent of coronary artery disease would be expected to have a greater effect on inducible QT dispersion.

Topical Treatment of Venous Microangiopathy in Patients with Venous Ulceration with Essaven Gel A Placebo-Controlled, Randomized Study

Carotid artery atherosclerosis is a strong predictor of stroke and represents a potential source of cerebral emboli. The aim of this study was to investigate whether an association exists between mitral annular calcification and carotid atheroma. In addition, the characteristics of carotid atheromas were compared between patients with and without mitral annular calcifica tion. The authors found that there was a significant association between the presence of mitral annular calcification and carotid atheroma. Mitral annular calcification in the elderly may be a form of atherosclerosis.

Imaging of coronary artery fistulas by multidetector computed tomography: is multidetector computed tomography sensitive?

Coronary angiography is the gold standard for diagnosing coronary artery fistulas (CAFs). Multidetector computed tomography (MDCT) is a recently developed imaging technique for detecting coronary artery stenosis, coronary artery anomalies, and coronary artery fistulas and their courses.

Increased dispersion of refractoriness in patients with atrial fibrillation in the early postoperative period after coronary artery bypass grafting.

Preoperative EP Characteristics of Post‐CABG AF. Introduction: Increased atrial effective refractory period (AERP) dispersion is well correlated with vulnerability to atrial fibrillation (AF). However, the preoperative electrophysiologic characteristics of atrial abnormalities that may play an important role in the development of AF postoperatively in patients with coronary artery bypass grafting (CABG) have not been investigated in detail.

Prognostic Significance of Neutrophil Gelatinase–Associated Lipocalin in ST-Segment Elevation Myocardial Infarction

Objectives This study investigated the prognostic value of neutrophil gelatinase–associated lipocalin (NGAL) in patients with ST-segment elevation myocardial infarction (STEMI). Background Neutrophil gelatinase–associated lipocalin is a promising biomarker for acute kidney injury. Recently, it was concluded that NGAL may be used beyond the boundaries of renal physiopathology. It was found to be an important factor indirectly contributing to the inflammatory processes. Little is known regarding its predictive role in STEMI. Methods One hundred six consecutive patients who underwent percutaneous coronary intervention (PCI) for STEMI and control group consisted of age- and sex-matched 60 consecutive patients with chest pain admitted to the hospital for elective PCI. According to median NGAL level, patients were classified into high- and low-NGAL groups. Results Neutrophil gelatinase–associated lipocalin levels were higher in patients with STEMI compared to the elective PCI group subjects. Inhospital and 1-year mortality rates were found to be significantly greater in patients with high NGAL. In addition, inhospital and 1-year major adverse cardiovascular event rates were significantly greater in the high-NGAL group, compared to the low NGAL group. High NGAL level on admission was a significant predictor for long-term mortality and major adverse cardiovascular events. The receiver operating characteristics curve analysis further illustrated that NGAL level on admission is a strong indicator of mortality, with an area under the curve of 0.76 (95% confidence interval, 0.62–0.89). Conclusions High NGAL levels may be associated with poor prognosis after PCI in patients with STEMI. However, further studies with larger numbers of patients and longer follow-up are required to evaluate the usefulness of plasma NGAL level for predicting prognosis of STEMI.

Elevated plasma asymmetric dimethylarginine level in acute myocardial infarction patients as a predictor of poor prognosis and angiographic impaired reperfusion

OBJECTIVES We aimed to investigate the effects of admission asymmetric dimethylarginine (ADMA) levels on myocardial perfusion and prognosis in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). BACKGROUND ADMA, an endogenous inhibitor of endothelial nitric oxide synthase, was found to be elevated in plasma of patients with cardiovascular risk factors. METHODS 168 consecutive patients undergoing primary PCI for STEMI <12 h after symptom onset and 75 healthy age and sex matched volunteer controls were enrolled in the study. Patients with STEMI were grouped into tertiles according to their admission plasma ADMA levels. Major adverse cardiac events during hospitalization or at one-year clinical follow-up were evaluated. Also angiographic impaired reperfusion was assessed by 3 different methods after PCI: angiographic thrombolysis in myocardial infarction (TIMI) flow, TIMI frame count and TIMI myocardial perfusion grade (TMPG). RESULTS Plasma level of L-arginine were lower in patients with STEMI than in the control group subjects, whereas plasma ADMA levels were increased in the STEMI patient group. The rate of impaired angiographic reperfusion increased across the tertile groups. Also one-year mortality rates showed a significant increase across the tertile groups (4% vs. 10% vs. 20%, p<0.01). Using multiple Cox regression analysis, only TIMI risk score, left ventricle ejection fraction (LVEF), abnormal TMPG, and increased ADMA values on admission emerged as independent predictors of one-year mortality. The ROC analysis indicated an optimal cut-point of ≥1.37 μmol/L, which detects one-year mortality with a negative predictive value of 96%. CONCLUSIONS In STEMI patients undergoing primary PCI, high admission ADMA levels were found to be associated with impaired myocardial perfusion and increased one-year mortality. Therefore admission ADMA level detection may be helpful in identifying the patients at a greater risk of impaired myocardial perfusion and poor prognosis.

Coagulation, fibrinolytic system activation and endothelial dysfunction in patients with mitral stenosis and sinus rhythm

Anticoagulation treatment can prevent systemic embolism in patients with mitral stenosis (MS) and atrial fibrillation (AF), but this treatment is under debate if patients are in sinus rhythm. The authors aimed to determine the hemostatic changes in patients with MS and sinus rhythm. Forty-six patients (28 in sinus rhythm and 18 in AF) with mitral stenosis were enrolled in this study. They studied systemic venous fibrinogen, D-dimer, antithrombin-III, tissue plasminogen activator (tPA), plasminogen activator inhibitor-I (PAI-I), von Willebrand factor (vWF), and platelet factor 4 (PF 4) in these patients. The patients were first classified according to their rhythm as sinusal and AF, and then according to the presence of left atrial spontaneous echo contrast (LASEC). Fibrinogen, D-dimer, antithrombin-III, vWF, and PF 4 levels were significantly greater in patients with MS and sinus rhythm or atrial fibrillation compared to the control group (p<0.05). Whether the rhythm was sinus or AF, fibrinogen, D-dimer, antithrombin-III, vWF, and PF 4 levels were significantly higher in patients with LASEC than in the control group (p<0.05). Only PF 4 was higher in the AF group than in those with sinus rhythm (p<0.05). As to plasminogen activator and PAI-I levels, only tissue plasminogen activator levels were found to be higher in the AF group than in those with sinus rhythm and the control group (p<0.05). In patients with mitral stenosis and sinus rhythm, if LASEC is present, coagulation activation, platelet activation, and endothelial dysfunction are similar in patients with AF, and anticoagulation should be considered in these patients.

Association between plasma asymmetrical dimethylarginine activity and severity of aortic valve stenosis

Objectives Aortic valve stenosis is the most common valvular heart disease in the Western world. The most common cause of aortic valve stenosis in adults is calcification of a normal trileaflet or congenital bicuspid valve. Calcific aortic valve stenosis is an active disease process characterized by mechanical stress, endothelial damage, lipid accumulation, inflammation, synthesis of extracellular matrix proteins, and calcification, reminiscent of atherosclerosis in many aspects. Asymmetrical dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase which reduces the bioavailability of nitric oxide and begets endothelial dysfunction. The goal of this study was to examine the association between ADMA activity and severity of aortic valve stenosis. Methods One hundred and nine patients were included in this study. Patients were grouped as those with mild aortic stenosis (42 patients, group 1), moderate aortic stenosis (36 patients, group 2), and severe aortic stenosis (31 patients, group 3). ADMA activity was measured by ELISA kit. Results Mean ADMA activity in group 3 was significantly higher than that in groups 1 and 2 (1.94 ± 0.45 vs. 0.87 ± 0.37 μmol/l, P < 0.001 and 1.94 ± 0.45 vs. 1.34 ± 0.52 μmol/l, P < 0.001, respectively). Serum ADMA activity was positively correlated with mean aortic gradient and maximum aortic gradient and negatively correlated with aortic valve area. Conclusion Our results showed that serum ADMA activity is higher in patients with severe aortic valve stenosis. ADMA activity is positively correlated with aortic valve stenosis severity. Serum ADMA level may be used as a precious marker to evaluate and follow up the severity of aortic valve stenosis.

Ambulatory blood pressure variability is associated with restenosis after percutaneous coronary intervention in normotensive patients

BACKGROUND Previous studies have showed that BP variability is associated with cardiovascular events. However, no data were available regarding binary restenosis as an end-point after percutenous coronary intervention (PCI). METHODS AND RESULTS This multicenter study included 100 consecutive normotensive patients with stable coronary artery disease who were planned for PCI. Before the index procedure, office BP and 24-h ambulatory BP measurements were performed. BP variability indices including systolic and diastolic 24-h average, the day and the night values of standard deviation (SD) and variation coefficient (VC) were measured and calculated. All patients underwent repeat coronary angiography at 6-month. According to angiographic results, 2 groups were formed; a restenosis group (n=30) with binary restenosis of the stented segment and a control group (n=70) with a stenosis diameter of <50% in stented segment. Systolic SD and VC values for 24-h average (14.0±2.8mmHg vs. 9.5±1.6mmHg, p<0.001 and 16%±3 vs. 11%±2, p<0.001, respectively), the day (15.2±3.9mmHg vs. 10.6±1.7mmHg, p<0.001 and 17%±4 vs. 12%±2, p<0.001, respectively), and the night (12.8±4.1mmHg vs. 8.4±2.4mmHg, p<0.001 and 14%±5 vs. 11%±3, p=0.004, respectively) values were significantly higher in restenosis group compared to control group. Similarly, diastolic SD and VC values for 24-h average (10.6±2.5mmHg vs. 8.1±1.5mmHg, p<0.001 and 12%±3 vs. 9%±2, p=0.001, respectively), the day (11.1±2.9mmHg vs. 9.0±1.8mmHg, p=0.003 and 12%±3 vs. 10%±2, p=0.006, respectively), and the night (10.0±3.6mmHg vs. 7.2±2.0mmHg, p=0.001 and 11%±5 vs. 9%±3, p=0.059, respectively) values were significantly higher in restenosis group compared to no restenosis group except for diastolic VC night. All systolic and diastolic BP variability indices except diastolic VC night were found to be independent predictors of risk of restenosis in multivariate analysis. In addition, the cut-off values of 11.4mmHg and 13% for 24-h systolic SD and VC, respectively, were found to be highly sensitive (93% for both) and specific (94% and 91%, respectively) for predicting binary restenosis at 6-month after PCI. CONCLUSIONS BP variability indices are significantly and independently associated with binary restenosis and higher values can predict restenosis after PCI sensitively and specifically.