Assessment of atrial electromechanical interval and P wave dispersion in patients with polycystic ovary syndrome.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is associated with increased cardiovascular risk, including ischemic stroke. Prolonged atrial electromechanical interval (EMI) is related to increased atrial fibrillation (AF) risk. The aim of the study is to evaluate atrial EMI and electrocardiographic P-wave indices related to increased AF risk in patients with PCOS. METHODS: Forty PCOS patients diagnosed on the basis of the Rotterdam criteria and 20 age-matched controls were prospectively included. patients with atrioventricular or intraventricular conduction abnormalities, dysrhythmia or taking antiarrhythmic drugs, atherosclerotic heart disease, cardiomyopathies, valvular lesions, pericardial disease, a history of pulmonary emboli or pulmonary hypertension, and abnormal thyroid function were excluded. Intra and interatrial EMI were measured by tissue Doppler imaging and P-wave dispersion (Pd) was calculated on 12-lead electrocardiography (ECG). The Isovolumetric relaxation time was the interval between the aortic valve closure artifact at the end of the LV outflow envelope and the mitral valve opening artifact at the beginning of the mitral E wave. RESULTS: Patients with PCOS had significantly higher interatrial [38 (24-65) ms vs. 16 (9-19) ms p<0.001], left-sided intra-atrial (14.8±6.1 vs. 7±1.7 ms, p<0.001), and right-sided intra-atrial (22.3±8.1 vs. 8.6±3.6 ms, p<0.001) EMI compared with the control group. Pd was significantly greater in the PCOS group compared with control group [45 (27-60) ms vs. 30 (26-38) ms, p<0.001]. Echocardiographic parameters of atrial EMI were significantly correlated with body mass index, Pd, and isovolumetric relaxation time in patients with PCOS. CONCLUSION: PCOS is associated with prolonged inter- and intra-atrial conduction times, which are related to increased AF risk.

A new risk scoring model for prediction of poor coronary collateral circulation in acute non-ST-elevation myocardial infarction.

BACKGROUND: We aimed to investigate the clinical features associated with development of coronary collateral circulation (CCC) in patients with acute non-ST-elevation myocardial infarction (NSTEMI) and to develop a scoring model for predicting poor collateralization at hospital admission. METHODS: The study enrolled 224 consecutive patients with NSTEMI admitted to our coronary care unit. Patients were divided into poor (grade 0 and 1) and good (grade 2 and 3) CCC groups. RESULTS: In logistic regression analysis, presence of diabetes mellitus, total white blood cell (WBC) and neutrophil counts and neutrophil to lymphocyte ratio (NLR) were found as independent positive predictors of poor CCC, whereas older age (≥ 70 years) emerged as a negative indicator. The final scoring model was based on 5 variables which were significant at p < 0.05 level following multivariate analysis. Presence of diabetes mellitus, and elevated total WBC (≥ 7.85 × 103/µL) and neutrophil counts (≥ 6.25 × 103/µL) were assigned with 2 points; high NLR (≥ 4.5) with 1 point and older age (≥ 70 years old) with -1 point. Among 30 patients with risk score ≤ 1, 29 had good CCC (with a 97% negative predictive value). On the other hand, 139 patients had risk score ≥ 4; out of whom, 130 (with a 93.5% positive predictive value) had poor collateralization. Sensitivity and specificity of the model in predicting poor collateralization in patients with scores ≤ 1 and ≥ 4 were 99.2% (130/131) and +76.3 (29/38), respectively. CONCLUSIONS: This study represents the first prediction model for degree of coronary collateralization in patients with acute NSTEMI.

Increased mean platelet volume in patients with infective endocarditis and embolic events.

BACKGROUND: Platelet activation appears to play an important role in thromboembolic complications of infective endocarditis (IE). Mean platelet volume (MPV) is a potentially useful marker of platelet activity and a quick and easy determinant of thrombotic risk. Hence the aim of this study was to investigate the baseline platelet volume indices (MPV and platelet distribution width [PDW]) in IE patients who developed embolic events in the follow-up period and who did not. METHODS: The study group consisted of 76 consecutive patients (female: 55, male: 21, mean age: 26 years old, ranged: 8-64 years) with definite IE according to Duke Criteria. Thirty four healthy subjects, who were age and gender adjusted, served as the control group. The mean duration of hospital stay was 44 days. RESULTS: Among the IE patients, 13 (13/76, 17.1%) had major embolic events. Significantly larger vegetations were observed in patients with embolic events as compared to non-embolic group (1.4 vs. 1.0 cm, p = 0.03). MPV at hospital admission was higher in patients who had embolic events in the follow-up period compared to both those who did not and the control subjects (10.62 ± 1.13 vs. 9.25 ± 0.97 and 8.93 ± 0.82 fL, p < 0.001, respectively). Similarly, the patients with embolic events had increased PDW compared to the non-embolic ones and the control group (16.31 ± 2.42 vs. 14.35 ± 1.97 and 14.04 ± 1.82%, p < 0.001, respectively). CONCLUSIONS: The present study demonstrated that IE patients with embolic events had increased MPV and PDW values, compared to non-embolics. Future prospective studies with standardized measurements may clarify the clinical role of platelet volume indices in thrombo-embolic complications of IE.

Impact of Aortic Stiffness Evaluated by Aortic Pulsatility on Fractional Flow Reserve.

BACKGROUND: Fractional flow reserve (FFR) is a highly reproducible, accurate and lesion-specific index to indicate inducible ischemia for a particular coronary artery lesion. Invasively measured aortic pulsatility (AP) is an indicator of aortic stiffness. In this study we aimed to evaluate the possible impact of AP in terms of aortic stiffness on FFR measurement. METHODS: In this study, we reviewed the FFR evaluation of 90 patients who had intermediate lesions (40-70% stenosis measured with quantitative coronary analysis) at the left anterior descending artery (LAD). AP was calculated as the ratio of aortic pulse pressure (systolic-diastolic pressure) to mean pressure. RESULTS: Aortic systolic pressure, aortic diastolic pressure, aortic pulse pressure and also aortic pulsatility did not differ significantly between patients with FFR ≤ 0.80 and FFR > 0.80 (p = 0.44, p = 0.28, p = 0.93 and p = 0.41, respectively). In subgroups arranged according to the degree of luminal narrowing (40-50%, 51-60%, and 61-70%), we did not observe significant correlation between AP and FFR value in subgroups with 40-50% and 51-60% lesions (r = 0.03, p = 0.95 and r = 0.07, p = 0.69, respectively). However, a statistically significant negative correlation between FFR value and AP in the subgroup of patients with 61-70% lesions was detected (r = -0.54, p = 0.04). CONCLUSIONS: These findings suggested that aortic stiffness might have a possible impact on FFR measurement in coronary lesions of 61-70% stenosis evaluated quantitatively. KEY WORDS: Aortic pulsatility; Fractional flow reserve; Stiffness.

Increased mean platelet volume in rheumatic mitral stenosis: assessment of clinical and echocardiographic determinants.

BACKGROUND AND AIM: The aim of this study was to investigate mean platelet volume (MPV) in patients with rheumatic mitral stenosis (RMS) and to define the determinants of a possible platelet activation reflected as platelet volume enlargement. METHODS: Peripheral venous plasma value of MPV was measured in 84 consecutive patients (16 men, 68 women; mean age ± SD = 44 ± 13 years) with RMS who had no left atrial thrombus by transoesophageal echocardiography. The control group consisted of 32 healthy subjects (nine men, 23 women; mean age ± SD = 38 ± 7 years). RESULTS: The patients had significantly higher MPV values (mean ± SD = 10.07 ± 0.58 fL) compared to the healthy subjects (mean ± SD = 8.15 ± 0.60 fL, p < 0.001). Among many clinical and echocardiographic variables, left atrial spontaneous echo contrast-positivity (beta = 0.426, p < 0.001) and severe mitral regurgitation (beta = 0.577, p < 0.001) appeared as significant predictors of platelet enlargement in RMS in multiple linear regression analysis. CONCLUSIONS: Patients with RMS have increased platelet activity reflected as elevated MPV; and the coexistence of severe mitral regurgitation and presence of left atrial spontaneous echo contrast are determinants of this increment.

Impact of continuous positive airway pressure therapy on atrial electromechanical delay and P-wave dispersion in patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea (OSA) has been shown to be associated with atrial fibrillation (AF). Prolongation of inter- and intraatrial conduction times during sinus rhythm has also been shown to be related to AF generation. Nasal continuous positive airway pressure (CPAP) is an effective treatment modality of OSA. METHODS: Twenty-four OSA patients diagnosed through polysomnography and 18 controls were included in the study. The basal inter- and intraatrial electromechanic delays prior to onset of the therapy were measured using tissue Doppler imaging. P-wave dispersion (Pd) was calculated on the basis of 12-lead electrocardiography. Same measurements were performed in OSA patients 6 months after the initiation of the therapy. RESULTS: Interatrial (39.2 ± 8 vs. 21.1 ± 2.8 ms, P < 0.001), left intraatrial (20.5 ± 7.2 vs. 11.1 ± 2 ms, P = 0.003), and right intraatrial electromechanical delays (20.7 ± 11 vs. 10 ± 2.6 ms, P < 0.001) prior to CPAP therapy were found to be significantly greater in OSA group as compared with the controls. Pd was also greater in the OSA group as compared with the controls (44 ± 7 vs. 28.5 ± 4 ms, P < 0.001). However, significant improvement has been noted after 6 months of CPAP therapy in interatrial (P < 0.0001), left intraatrial (P = 0.002), and right intraatrial electromechanical delays (P < 0.0001) as well as in Pd (P < 0.0001) as compared to baseline values in patients with OSA. CONCLUSION: Our findings suggested that CPAP therapy provides more homogenous conduction through atria in patients with OSA. This effect may translate into decreased risk for AF associated with OSA.

Impact of metabolic syndrome on fractional flow reserve.

OBJECTIVE: Fractional flow reserve (FFR) assessment is widely used to determine significance of intermediate coronary lesions. Previously, components of the metabolic syndrome (MS) which may affect FFR validity were not tested cumulatively. In this study, we investigate the possible effect of MS on FFR assessment. METHODS AND RESULTS: We retrospectively evaluated 178 consecutive patients who had undergone FFR assessment. Thirty-two patients were excluded. All of the coronary lesions were in the left anterior descending artery. They were evaluated with quantitative coronary angiography (QCA). In 105 patients the MS was present and 41 patients were without the MS. According to the severity of the coronary lesions in QCA, patients were divided into three groups: 40-50%, 51-60% and 61-70% lesions. FFR measurements were compared in each group with respect to MS presence. Coronary artery lesions were accepted as haemodynamically significant if FFR < or = 0.80. Age of the population, lesion length, lesion diameter and adenosine dosage performed during FFR assessment were not different between patients with MS or without MS. When the lesions were divided into three categories according to the severity of the luminal narrowing expressed in stenosis percentages as 40-50, 51-60, and more than 61%, the observed FFR values decreased with advancing lesion category (P = 0.04). However, observed FFR values did not differ between the patients with MS and without MS in each category (P = 0.88). After exclusion of the diabetic patients, FFR values still did not differ between the patients with MS and without MS in each category (P = 0.78). CONCLUSIONS: Presence of the metabolic syndrome has no significant effect on FFR assessment. This study provides additional data for the reliability of FFR in patients with MS.