Arif Oguzhan Cimen

Effect of intracoronary streptokinase administered immediately after primary percutaneous coronary intervention on long-term left ventricular infarct size, volumes, and function.

OBJECTIVES The purpose of this study was to investigate the reflections of the improvement in microvascular perfusion provided by adjuvant intracoronary streptokinase (ICSK) on late-phase infarct size and left ventricular volumes and functions. BACKGROUND It has been shown that ICSK given immediately after primary percutaneous coronary intervention (PCI) improves myocardial perfusion in the early days of ST-segment elevation acute myocardial infarction. METHODS Ninety-five patients undergoing primary PCI were randomized to ICSK 250 kU (n = 51) or no additional therapy (n = 44). Two days later, coronary hemodynamic indexes were measured to evaluate tissue-level perfusion. After 6 months, angiography, echocardiography, and technetium-99m single-photon emission computed tomography (SPECT) were performed. RESULTS At 2 days, all indexes of microvascular function were significantly better in the ICSK group than in the control group, including coronary flow reserve (2.5 vs. 1.7, p < 0.001) and index of microvascular resistance (20.2 vs. 34.2, p < 0.001). At 6 months, infarct size (22.7% vs. 32.9%; p = 0.003) and left ventricular end-systolic (41.1 ml vs. 60.9 ml; p = 0.009) and end-diastolic volumes (95.5 ml vs. 118.3 ml; p = 0.006) were significantly smaller, and the ejection fraction was significantly higher (57.2% vs. 51.8%; p = 0.018) in the ICSK group compared with the control group. CONCLUSIONS In this study, it has been demonstrated that low-dose ICSK given immediately after primary PCI significantly limits long-term infarct size and preserves left ventricular volumes and functions. (Effect of Complementary Intracoronary Streptokinase Administration Immediately After Primary Percutaneous Coronary Intervention on Microvascular Perfusion and Late Term Infarct Size in Patients With Acute Myocardial Infarction; NCT00302419).

Coronary Flow Velocity Reserve and Carotid Intima Media Thickness in Patients with Autosomal Dominant Polycystic Kidney Disease: From Impaired Tubules to Impaired Carotid and Coronary Arteries

BACKGROUND AND OBJECTIVES Cardiovascular problems are a major cause of morbidity and mortality in patients with autosomal dominant polycystic kidney disease. Endothelial dysfunction, an early and reversible feature in the pathogenesis of atherosclerosis, is associated with increased vascular smooth muscle tone, arterial stiffening, and increased intima-media thickness. Coronary flow velocity reserve is a noninvasive test showing endothelial function of epicardial coronary arteries and coronary microcirculatory function. The aim of the study was to investigate the carotid intima-media thickness and coronary flow velocity reserve in patients with autosomal dominant polycystic kidney disease. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Thirty normotensive patients with autosomal dominant polycystic kidney disease (10 male, 20 female) with well-preserved renal function and 30 healthy subjects (12 male, 18 female) were included in the study. Coronary flow velocity reserve was measured at baseline and after dipyridamole infusion by echocardiography. Coronary flow velocity reserve was calculated as the ratio of hyperemic to baseline diastolic peak velocities. RESULTS Carotid intima-media thickness was significantly higher in patients than in control subjects (0.80 +/- 0.29 versus 0.54 +/- 0.14 mm, respectively; P < 0.001). Moreover, coronary flow velocity reserve was significantly lower in patients than in control subjects (1.84 +/- 0.39 versus 2.65 +/- 0.68, respectively; P < 0.001). CONCLUSIONS Normotensive patients with autosomal dominant polycystic kidney disease with well-preserved renal function have significantly increased carotid intima-media thickness and significantly decreased coronary flow velocity reserve compared with healthy subjects. These findings suggest that atherosclerosis starts at an early stage in the course of their disease in patients with autosomal dominant polycystic kidney disease.

Coronary flow reserve dysfunction in hemodialysis and kidney transplant patients

Abstract: Background:  The assessment of coronary flow reserve (CFR) by trans‐thoracic echocardiography has recently been introduced into clinical studies. Impairment of coronary microvascular functions and decreased CFR detected by trans‐thoracic Doppler harmonic echocardiography (TTDE) has recently been reported in hemodialysis (HD) patients, but there is no comparative study between HD patients and renal transplant recipients.

Concurrent Microvascular and Infarct Remodeling After Successful Reperfusion of ST-Elevation Acute Myocardial Infarction

Background—Connection between the course of microvascular and infarct remodeling processes over time after reperfused ST-elevation acute myocardial infarction has not been fully elucidated. The aim of this study is to investigate the association of temporal changes in hemodynamics of microcirculation in the infarcted territory and infarct size (IS) after primary percutaneous coronary intervention in patients with ST-elevation acute myocardial infarction. Methods and Results—Thirty-five patients admitted with ST-elevation acute myocardial infarction undergoing primary percutaneous coronary intervention were enrolled in the study. Coronary flow reserve (CFR), index of microvascular resistance (IMR), and IS were assessed 2 days after primary percutaneous coronary intervention and at the 5-month follow-up. The predictors of the 5-month IS were the baseline values of IS (&bgr;=0.6, P<0.001), IMR (&bgr;=0.280, P=0.013), and CFR (&bgr;=−0.276, P=0.017). There were significant correlations between relative change in IS and relative change in measures of microvascular function (IS and CFR [r=−0.51, P=0.002]); IS and IMR ([r=0.55, P=0.001]). In multivariate model, relative changes in IMR (&bgr;=0.552, P=0.001) and CFR (&bgr;=−0.511, P=0.002) were the only predictors of relative change in IS. In patients with an improvement in IMR >33%, the mean IS decreased from 32.3±16.9% to 19.3±14% (P=0.001) in the follow-up. Similarly, in patients with an improvement in CFR >41%, the mean IS significantly decreased from 29.9±20% to 15.8±12.4% (P=0.003). But in patients with an improvement in IMR and CFR, which were below than the mean values, IS did not significantly decrease during the follow-up. Conclusions—Improvement in microvascular function in the infarcted territory is associated with reduction in IS after reperfused ST-elevation acute myocardial infarction. This link suggests that further investigations are warranted to determine whether therapeutic protection of microvascular integrity results in augmentation of infarct healing.

Effect of Cigarette Smoking on Platelet Aggregation

Background: Cigarette smoking may increase platelet aggregation and cause atherothrombotic cardiovascular events. We aimed to investigate the impact of cigarette smoking on platelet function in patients with ischemic coronary heart disease (CHD).Methods: Twenty patients with ischemic stable CHD under aspirin therapy (300 mg/d), who continue to smoking despite all warnings, and 20 nonsmokers with CHD are enrolled in the study. Platelet function is studied at the morning, before and 15 minutes after the first cigarette, by the Platelet Function Analyzer (PFA)-100, with collagen and epinephrine and collagen and adenosine diphosphate cartridges. Post aspirin platelet hyperactivity is defined as having a closure time (CT) shorter than 186 seconds despite regular aspirin intake. Serial CT measurements are analyzed by paired samples t test.Results: Persistent platelet activity was present in 4 smoker (20%) and 3 nonsmoker (15%) patients at the beginning. Platelet activity measured by the PFA-100 is been increased significantly after cigarette smoking (P = .004). Shorter CTs were determined after smoking in all patients with and without baseline persistent platelet activity, and 4 more participants became aspirin nonresponder (P = .004). No significant differences in demographic, hematological, and biochemical parameters were determined between aspirin responders and nonresponders.Conclusions: We determined that cigarette smoking may increase platelet aggregation in patients with ischemic CHD in an aspirin nonresponsive manner. Our results emphasize the importance of quitting cigarette smoking in patients with CHD.

Association between chronic hepatitis C infection and coronary flow reserve in dialysis patients with failed renal allografts.

BACKGROUND Hepatitis C infection occurs frequently among patients with end-stage renal disease and increases the risk of atherosclerotic cardiovascular diseases. Endothelial dysfunction (ED) is an early event in the pathogenesis of atherosclerosis. It has been reported among patients treated with hemodialysis (HD), peritoneal dialysis (PD), or renal transplantation. The aim of the present study was to evaluate effects of chronic hepatitis C infection on ED in patients with failed renal transplants. METHODS Twenty-six nondiabetic, anti-hepatitis C virus (HCV)-positive (15 females, mean age: 38 +/- 8 years) and 26 anti-HCV-negative patients (15 females, mean age: 36 +/- 5 years), all of whom had returned to PD or HD after renal transplant failure were studied to assess coronary flow reserve (CFR) by transthoracic Doppler echocardiography. Serum high-sensitivity C-reactive protein (hs-CRP) levels were measured as markers of chronic inflammation. CFR recordings and intima-media thickness measurements were performed using the Vivid 7 echocardiography device. RESULTS Demographic and clinical characteristics of patients were similar between the two groups. Serum hs-CRP levels were significantly higher among HCV-positive patients versus HCV-negative counterparts. HCV-positive patients showed lower CFR measurement than HCV-negative ones. Also, a negative correlation was observed between serum hs-CRP levels and CFR values. CONCLUSION CFR values are worse among anti-HCV-positive patients with failed renal transplants compared with anti-HCV-negative subjects. Graft dysfunction per se may aggravate a proinflammatory states thereby inducing ED. Furthermore, the presence of HCV is a greater trigger of ED among patients with renal failed grafts.

Coronary flow reserve is impaired in patients with adult growth hormone (GH) deficiency

Objective  Relationship between adult growth hormone deficiency (AGHD) and increased cardiovascular disease risk is very well known in hypopituitary patients treated with conventional hormone replacement therapy other than growth hormone (GH) administration. Endothelial dysfunction, an early and reversible event in pathogenesis of atherosclerosis, is associated with increased vascular smooth muscle tone, arterial stiffening and intima‐media thickness (IMT). Coronary flow reserve (CFR) measurement by transthoracic Doppler echocardiography (TTDE) reflects coronary microvascular and endothelial functions, as a cheaper and an easy screening test. We have used TTDE to evaluate endothelial function and coronary microvascular function in AGHD.

Endothelial dysfunction in hemodialysis patients with failed renal transplants

Gorgulu N, Yelken B, Caliskan Y, Elitok A, Cimen AO, Yazici H, Oflaz H, Golcuk E, Ekmekci A, Turkmen A, Yildiz A, Sever MS. Endothelial dysfunction in hemodialysis patients with failed renal transplants.
Clin Transplant 2009 DOI: 10.1111/j.1399‐0012.2009.01160.x
© 2009 John Wiley & Sons A/S.

The accuracy of deceleration time of diastolic coronary flow measured by transthoracic echocardiography in predicting long-term left ventricular infarct size and function after reperfused myocardial infarction

AIMS Assessment of microvascular function after reperfused acute myocardial infarction (AMI) provides important insights for myocardial reperfusion and facilitates prediction of long-term left ventricular (LV) function and clinical outcome. In this study, we examined microvascular integrity 48 h after successful primary percutaneous coronary intervention (PCI) and compared predictive accuracy of the intracoronary pressure-wire- and transthoracic Doppler echocardiography-based parameters in the estimation of long-term LV infarct size and function. METHODS AND RESULTS The study group consisted of 30 anterior AMI patients who were treated successfully with primary PCI. Two days after primary PCI, microvascular integrity was evaluated. Coronary flow reserve (CFR), collateral flow index (CFIp), coronary wedge pressure (CWP), and index of microvascular resistance (IMR) were determined using intracoronary pressure wire. Deceleration time of coronary diastolic flow (DDT) was measured using transthoracic echocardiography. At 6 months, coronary angiography, echocardiography, and infarct size measurement were performed. Area under the curve, sensitivity, and specificity of the indices of microvascular perfusion in the prediction of late-term infarct size were as follows: IMR (0.68 ± 0.15, 69%, 60%), CFR (0.67 ± 0.10, 66%, 59%), CWP (0.69 ± 0.12, 70%, 72%), CFIp (0.64 ± 0.10, 65%, 78%), and DDT (0.68 ± 0.16, 69%, 79%). All of the microvascular perfusion indices, which have been used in this study, had comparable sensitivity and specificity in the prediction of long-term ejection fraction. There were no significant differences between areas under the curve of microvascular perfusion indices in the prediction of long-term infarct size and ejection fraction. CONCLUSION As a non-invasive parameter, DDT was found to be as accurate as the invasive parameters of microvascular function in estimating long-term infarct size and LV function. Thus, simply measuring DDT in the reperfused infarct-related artery might provide useful and reliable estimate for early risk stratification.

Reduced Coronary Flow Reserve and Early Diastolic Filling Abnormalities in Patients with Nephrotic Syndrome

Background. Increased cardiovascular disease risk is very well known in nephrotic syndrome. Coronary flow reserve measurement by trans-thoracic echocardiography reflects coronary microvascular and endothelial function. However, diastolic filling abnormalities by echocardiography may indicate diastolic dysfunction. Our aim was to evaluate endothelial and diastolic functions by trans-thoracic echocardiography in nephrotic syndrome. Methods. Eighteen patients with nephrotic syndrome (five females, 34 ± 17 years) and 30 controls (10 females, 35 ± 10 years) were evaluated in this cross-sectional observational study. Age, weight, lipid profile, glucose, blood urea nitrogen, creatinine, serum albumin, total protein, C-reactive protein, erythrocyte sedimentation rate, blood pressures, 24-hour urine volume, and protein were recorded. Glomerular filtration rate was estimated by Cockcroft-Gault Formula. Doppler flow and other echocardiographic parameters were measured by Vivid 7 echocardiography. Results. Coronary flow reserve was significantly lower in patients than controls (p < 0.001) and was negatively correlated with proteinuria (p < 0. 001), creatinine levels (p = 0.03), total cholesterol (p = 0.02), C-reactive protein (p = 0.02), and erythrocyte sedimentation rate (p = 0.005). E/A ratio was significantly lower in patients than in controls (p = 0.005). DT was significantly higher in patients than in controls (p = 0.01) and isovolumic relaxation time was similar in both groups. Conclusion. Coronary flow reserve and left ventricular diastolic filling are significantly impaired in nephrotic syndrome. Proteinuria, serum creatinine, total cholesterol and inflammation may have all contributory effects on endothelial dysfunction. Early evaluation of patients with nephrotic syndrome should include coronary flow and diastolic function by echocardiography.