Goksel Guz

Cardiac Biomarkers and Noninvasive Predictors of Atherosclerosis in Chronic Peritoneal Dialysis Patients

Background: We investigated the relationship among serum cardiac biomarkers including N-terminal pro-brain natriuretic peptide (NT-pro-BNP), cardiac troponin T (cTnT), uric acid and high-sensitive C-reactive protein (hs-CRP) and noninvasive predictors of atherosclerosis including carotid intima-media thickness (IMT), aortic stiffness (pulse wave velocity (PWV)) and transthoracic coronary flow reserve (CFR) in peritoneal dialysis (PD) patients. Methods: 37 PD patients were included in the study. We measured (1) carotid IMT, (2) PWV and augmentation index (AIx), and (3) CFR. Simultaneous measurements of serum NT-pro-BNP, cTnT, uric acid and hs-CRP were also performed. Associations among these variables were analyzed. Results: cTnT was significantly associated with carotid IMT (r = 0.747, p < 0.001), PWV (r = 0.431, p = 0.035) and CFR (r = –0.439, p = 0.007). In multivariate analysis, cTnT was a significant independent predictor of carotid IMT (β = 4.446, p < 0.001) and CFR (β = –2.272, p = 0.013). Patients with high cTnT levels (≥0.01 ng/ml) significantly hadhigher carotid IMT and PWV values. Only the aortic PWV significantly correlated with residual renal function (r = –0.574, p = 0.004). Conclusions: Serum cTnT appeared to be a useful clinical biomarker for evaluating noninvasive predictors of atherosclerosis in chronic PD patients. Arterial stiffness as determined by PWV is also correlated with residual renal function.

The preoperative cardiology consultation: goal settings and great expectations

Background Despite the availablity of guidelines for preoperative cardiology consultations, their effi cacy in real clinical practice remains unknown. Furthermore, there are concerns that overused cardiology consultations can lead to unnecessary investigations, prolonged hospital stays, and even cancellation of necessary surgery. In this retrospective study, we investigated: (i) the potential impact of the American Heart Association/American College of Cardiology algorithm and (ii) the potential of this algorithm for preventing unnecessary evaluation. Methods We examined the cardiology consultation requests for 712 patients scheduled for elective surgery. Our analysis included: (i) patient characteristics, (ii) abnormalities revealed by the consultant, (iii) impact of these abnormalities on clinical decision making and therapy modifi cation. Results The most common reason for consultation was ‘pre-operative evaluation’ (80.9%). Although our cardiologists revealed an abnormality in 67.8% and recommended further work up in 58.7% of our patients, they contributed to the clinical course in only 36.9%. Moreover, when the algorithm was applied to ‘routine pre-operative evaluation’ requests lacking a specifi c question, only 7.6% of these consultation requests required further investigation. Conclusion Preoperative cardiology consultation seems to be overused. Although the fear of missing important issues leads surgeons to use a decreased threshold for pre-operative consultation requests, such a non-specifi c manner of pre-operative consultation request causes unnecessary investigations and decreased cost-eff ectiveness. Furthermore, the detection of any clinical abnormality by cardiologists surprisingly adds little to clinical decision making.

Percutaneous coronary intervention increases microvascular resistance in patients with non-ST-elevation acute coronary syndrome.

AIMS In the acute coronary syndrome setting, the interaction between epicardial coronary artery stenosis and microcirculation subtended by the culprit vessel is poorly understood. The purpose of the present study was to assess the immediate impact of percutaneous coronary intervention (PCI) on microvascular resistance (MR) in patients with non-ST-elevation myocardial infarction (NSTEMI). METHODS AND RESULTS Thirty-eight patients undergoing PCI for NSTEMI were recruited consecutively. Culprit lesions were stented over a Doppler and pressure-sensor-equipped guidewire. In the presence of epicardial stenosis, MR was calculated by taking collateral flow, as measured by the coronary wedge pressure, into consideration. After removal of epicardial stenosis, MR was calculated simply as distal coronary pressure divided by average peak velocity. When collateral flow was incorporated into the calculation, MR increased significantly from 1.70 ± 0.76 to 2.05 ± 0.72 (p=0.001) after PCI in the whole population. Periprocedural changes (Δ) in absolute values of MR and troponin T correlated significantly (r=0.629, p=0.0001). In patients who developed periprocedural myocardial infarction, MR increased significantly after PCI (1.48 ± 0.73 versus 2.28 ± 0.71, p<0.001). Nevertheless, removal of the epicardial lesion did not change MR in patients without periprocedural MI (1.91±0.73 versus 1.81±0.67, p=0.1). CONCLUSIONS When collateral flow is accounted for, removal of epicardial stenosis increases MR in patients with NSTEMI undergoing PCI.

There is an increased risk of atherosclerosis in hereditary angioedema.

BACKGROUND Hereditary angioedema is associated either with a deficiency in the amount or in the function of the C1 inhibitor (C1 INH). OBJECTIVE In this study the endothelial function of HAE patients was investigated to evaluate the impact of hereditary C1-INH deficiency on atherosclerosis, which has not yet been established before. METHODS A total of 26 patients (14 female, 12 male. Mean age: 38±13) diagnosed with HAE and 30 healthy controls were enrolled in the study. Measurement of coronary flow reserve (CFR) in the left anterior descending coronary artery was performed using transthoracic doppler harmonic echocardiography at baseline and following dipyridamol infusion. The intima-media thickness (IMT) in the carotid artery was measured using an echocardiographic system equipped with 10 MHz linear transducer (Vingmed System Five). RESULTS The mean CFR value for the HAE patient group was significantly lower than that of the control group (p<0.001). The mean IMT was not found to be significantly different between the two groups, although it was slightly higher in the HAE patient group. No correlation was found between the CFR and the disease severity scores, nor was it shown between the CFR values and the duration of danazol treatment. CONCLUSION Our results indicate that there is a microvascular endothelial dysfunction in HAE patients. Although carotid intima media thickness of these patients was not significantly increased, the presence of microvascular endothelial dysfunction might be regarded as an early indicator of a premature atherosclerosis.

Role of C-reactive protein in determining microvascular function in patients with non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention.

The extent of coronary microvascular dysfunction might be related, not only to patient characteristics and procedural factors, but also to the inflammatory status. The aim of the present study was to examine a possible association between inflammation, as reflected by the serum C-reactive protein (CRP) levels, and the extent of baseline and post-percutaneous coronary intervention (PCI) coronary microvascular dysfunction in patients with non-ST-segment elevation acute coronary syndrome undergoing PCI. A total of 42 patients undergoing PCI for non-ST-segment elevation acute coronary syndrome were enrolled. Coronary microvascular resistance (MR) was determined in the territory of culprit artery using a Doppler probe- and a pressure sensor-equipped guidewire both before (taking the collateral blood into account) and after PCI. The periprocedural changes in MR were calculated. The CRP levels at admission were correlated with the pre-PCI MR (r = 0.498, p = 0.001), post-PCI MR (r = 0.429, p = 0.005), and periprocedural changes in MR (r = 0.785, p <0.001). On multivariate regression analysis, the only predictor of the pre-PCI (β = 0.531, p = 0.002) and post-PCI (β = 0.471, p = 0.012) MR was the serum CRP concentration. Likewise, the periprocedural changes in MR was predicted by the serum CRP levels (β = 0.677, p = 0.001) and the presence of angiographic thrombus (β = -0.275, p = 0.02). In conclusion, these results have shown that the CRP level is related to increased coronary MR in the territory of the culprit lesion. This suggests that inflammatory processes might play a role in microvascular impairment in patients with non-ST-segment elevation acute coronary syndrome.

Cardiotrophin-1: A new predictor of atrial fibrillation relapses after successful cardioversion

We aimed to investigate whether or not cardiotrophin-1 (CT-1) can be used as a predictor of sinus rhythm constancy in patients with atrial fibrillation (AF) converted to sinus rhythm. Thirty two patients with AF (48-78 years), without any structural heart disease were enrolled for the study. The control group consisted of 32, age and gender matched healthy persons. Measurements of CT-1 were made after transthoracic and transesophageal echocardiography prior to cardioversion (CV). Relapses of AF were investigated by monthly electrocardiograms (ECGs) and ambulatory ECGs at 1st, 3rd, and 6th month. At the end of 6th month, measurements of CT-1 were repeated. At the beginning patients with AF had increased CT-1 levels when compared to controls (0.94 ± 0.32 pg/mL vs. 0.30 ± 0.12 pg/mL, [p < 0.001]). At the end of follow-up of the 32 patients, 17 (53%) had AF relapse. Age, initial duration of AF, left ventricle diameters, ejection fraction, left atrium appendix flow rates were similar among patients with and without AF relapse. However, basal left atrium diameter (4.24 ± 0.14 cm vs. 4.04 ± 0.22 cm, p = 0.005), pulmonary artery pressure (32.82 ± 5 vs. 28.60 ± 6.23 mmHg, p = 0.004) and CT-1 values (1.08 ± 0.37 vs. 0.82 ± 0.16 pg/mL, p = 0.02) were significantly increased in patients with AF relapse. Furthermore, patients with relapsed AF had higher CT-1 levels at 6th month when compared to those in sinus rhythm (1.00 ± 0.40 vs. 0.71 ± 0.23 pg/mL). We conclude that post-CV, AF relapses are more frequent among patients with increased baseline CT-1 levels, and CT-1 may be a potential predictor of AF relapse.

An aortic dissection treated with left main coronary artery stent implantation

Retrograde coronary aortic dissection is a rare but dangerous complication of coronary angioplasty. Mostly seen in right coronary artery procedures, especially in chronic total oclussion lesions, and rarely seen in left side procedures. This is a case report of an aortic dissection complicated by coronary angioplasty of the left circumflex artery. Immediate stenting of the left main coronary artery successfully sealed the entry point of dissection and stabilized the patient.