Peak Diastolic Flow Velocity Research Articles

Abstract O.57: Coronary Circulation Assessed by Transthoracic Echocardiography during Exercise Test is Impaired in Patients after Kawasaki Disease Even with Regressed Coronary Arterial Lesions

Background: Coronary flow reserve (CFR) has important clinical implications for the evaluation of coronary circulation including Kawasaki disease (KD). Pharmacological vasodilation is generally used to induce hyperemia for the assessment of CFR; however, exercise test provides more physiological stress. Objectives: This study sought to assess CFR during exercise in patients after KD with regressed coronary arterial lesions (CALs) by transthoracic echocardiography (TTE). Methods: Twenty KD patients were studied, comprising 8 patients with regressed CALs in the left anterior descending coronary artery (LAD) and 12 patients without CALs (median ages; 10 and 9 years, respectively). Fourteen age-matched healthy subjects were also studied as controls. We obtained peak diastolic coronary flow velocity (CFV) of the LAD by pulsed-Doppler TTE at rest and at submaximal exercise on supine ergometer. CFR was calculated as the ratio of exercise to rest CFVs. Results: The CFV measurements were obtained in all the subjects. There was no significant difference in the CFVs among the patients with regressed CALs, those without CALs and the controls (30 ± 7 vs. 31 ± 10 vs. 28 ± 8 cm/s, respectively). The CFVs increased during exercise in the patients without CALs and the controls (51 ± 11 and 49 ± 10 cm/s, respectively, both p <0.05). In consequence, the CFR was lower in the patients with regressed CALs compared with those without CALs and the controls (1.3 ± 0.2 vs. 1.7 ± 0.2 and 1.7 ± 0.2, respectively, p <0.05). Conclusions: Exercise test demonstrated impaired CFR in KD patients with regressed CALs. It suggests that these patients have risk of future myocardial ischemic events.

Nicorandil improves myocardial function by regulating plasma nitric oxide and endothelin-1 in coronary slow flow.

BackgroundCoronary slow flow (CSF) is a special coronary microvascular disorder. The pathogenesis and effective therapeutics of CSF remain unclear. This study aimed to evaluate the global and regional functions of the left ventricle (LV) and investigate the efficacy of nicorandil in patients with CSF.Patients and methodsThirty-six patients with CSF in the left anterior descending (LAD) branch and 20 patients with normal coronary arteries were included. Global and regional functions of the LV supplied by LAD were measured using conventional Doppler echocardiography and two-dimensional speckle tracking echocardiography, respectively, within 24 h after coronary angiography. Concentrations of plasma nitric oxide (NO) and endothelin-1 (ET-1) were detected using colorimetry and radioimmunoassay, respectively. The function of the LV and the levels of NO and ET-1 were also investigated before and 90 days after treatment with 15 mg/day of nicorandil.ResultsCompared with the control group, the early diastolic peak velocity (E), E/A ratio, and plasma NO levels were lower, whereas the late diastolic peak flow velocity (A) and plasma ET-1 levels were significantly higher in the CSF group (P<0.05). The longitudinal strain rate peak of the LV was reduced significantly in CSF patients (P<0.001). After treatment, 75% (27/36) of CSF patients were free of chest pain. The values of E peak, E/A ratio, longitudinal strain rate peak, and plasma NO level were increased (P<0.001), whereas the ET-1 level was decreased in CSF patients (P<0.001).ConclusionNicorandil may improve chest pain symptoms and the impaired function of the LV, possibly by increasing plasma NO and reducing ET-1 in CSF.

Coronary Flow Velocity Reserve in Patients with Ascending Aorta Aneurysm

Ascending aorta aneurysms (AAA) are one of the leading causes of morbidity and mortality. Impairment in coronary flow may contribute to cardiovascular consequences in AAA patients. Coronary flow velocity reserve (CFVR) has been considered an important diagnostic index of the functional capacity of coronary arteries noninvasively. The aim of this study was to evaluate, by noninvasive CVFR, whether patients with AAA demonstrate significant coronary microvascular dysfunction in the absence of coronary artery disease (CAD). We prospectively included 44 patients with thoracic AAA in the absence of concomitant CAD (30 men, 14 women; mean age 57.5±8.4years). A total of 36 patients without aortic dilatation (mean age 55.2±9.9years) were selected as the control group. Coronary flow velocities in the distal left anterior descending (LAD) artery were measured using transthoracic echocardiography. CFVR was calculated as the hyperemic to resting coronary diastolic peak velocities ratio. Compared with controls, patients with AAA had higher baseline LAD peak diastolic coronary flow velocities (28.3±5.8 vs. 25.2±4.5cm/sec, P=0.01), lower hyperemic LAD flow velocities (54.0±10.3 vs. 57.2±12.7cm/sec, P=0.220), and consequently lower CFVR (1.9±0.3 vs. 2.3±0.5, P<0.001). Multivariate linear regression analysis showed that CFVR was independently associated only with aortic systolic diameter (AoSD) (β=-0.679, P=<0.001). Our study demonstrates that noninvasive CFVR is significantly reduced in patients with AAA and AoSD is the most important determinant of impaired CFVR.

Use of Xinfeng capsule to treat abarticular pathologic changes in patients with rheumatoid arthritis

ObjectiveTo observe the influence of Xinfeng-capsule (XFC) on abarticular pathologic changes (APCs) and other indices of patients with rheumatoid arthritis (RA) and explore the mechanism of action of XFC in improving such changes. MethodsThree-hundred RA patients were divided randomly into a treatment group (n=150) and control group (n=150). A normal control (NC) group (n=90) was also created. Changes in cardiac function, pulmonary function, anemia indices and platelet parameters of RA patients were measured. Curative effects of the two groups were compared, and comparison carried out with the NC group. ResultsIn 300 RA patients, late diastolic peak flow velocity (A peak) was much higher (P<0.01) and early diastolic peak flow velocity (E peak), E/A, and left ventricular fraction shortening much lower (P<0.01) than those in the NC group. Vital capacity (VC), forced vital capacity in one second, forced vital capacity (FVC), maximal voluntary ventilation (MVV), maximal expiratory flow in 50% of VC (FEF50) and FEF75 were lowered remarkably (P< 0.05 or P<0.01). Platelet count (PLT), plateletcrit (PCT) and mean platelet volume (MPV) increased markedly (P<0.05 or P<0.01), and hemoglobin (Hb) level decreased significantly (P<0.05). After XFC treatment, the A peak and PLT and PCT were much lower (P<0.05), and E/A and the number of red blood cells as well as Hb level were much higher (P< 0.05), as were FVC, MVV and FEF50 (P<0.05 or P< 0.01), in the treatment group than those in the NC group. Total score of pain and swelling in joints, uric-acid level and high-sensitivity C-reactive protein level were much lower, and superoxide dismutase level as well as the number of CD4 + CD25 + regulation T cells (Treg) and CD4 + CD25 + CD127-Treg were much higher (P<0.05 or P<0.01) in the treatment group than those in the NC group. ConclusionRA patients with pathologic changes in joints also suffer from lower cardiac and pulmonary functions and from parameters of anemia and platelet factors. XFC can improve the symptoms of RA patients, ameliorate their cardiac and pulmonary functions and reduce the parameters of anemia and platelet factors. XFC lowers the immune inflammatory reaction to improve APCs in RA patients.

Impaired coronary microvascular and left ventricular diastolic function in patients with inflammatory bowel disease

Background and aimIncreased incidence of coronary vascular events in patients with inflammatory bowel disease (IBD) is known. However, the association between coronary microvascular function and IBD has not been fully defined. We aimed to investigate whether coronary flow reserve (CFR) and left ventricular diastolic function were impaired in IBD patients. MethodsSeventy-two patients with IBD (36 patients with ulcerative colitis [UC] and 36 Crohn's disease [CD]) were registered. Each subject was evaluated after a minimum 15-day attack-free period. For the control group, 36 age- and sex-matched healthy volunteers were included into the study. IBD clinical disease activity in UC was assessed by the Truelove–Witts Index (TWAS) and in CD by the Crohn's Disease Activity Index (CDAI). In each subject, CFR was measured through transthoracic Doppler echocardiography. ResultsCompared to the controls, the CD group and UC group had significantly higher high-sensitivity C-reactive protein (hs-CRP) and erythrocyte sedimentation rate. Baseline diastolic peak flow velocity (DPFV) of the left anterior descending artery (LAD) was significantly higher in the IBD group (24.1±3.9 vs. 22. 4±2.9, p<0.05), and hyperemic DPFV (56.1±12.5 vs. 70.6±15.3, p<0.05) and CFR (2.34±0.44 vs. 3.14±0.54, p<0.05) were significantly lower in the IBD group than in the control group. In stepwise linear regression analysis, hs-CRP and lateral Em/Am ratio were independently correlated with CFR. ConclusionCFR, reflecting coronary microvascular function, is impaired in patients with IBD. CFR and left ventricular diastolic function parameters are well correlated with hs-CRP.

Association between sleep quality and cardiovascular damage in pre-dialysis patients with chronic kidney disease.

BackgroundPoor sleep quality, a novel risk factor of cardiovascular diseases (CVD), is highly prevalent in patients with chronic kidney disease (CKD). The association between poor sleep quality and cardiovascular damage in patients with CKD is unclear. This study is aimed to assess the prevalence and related risk factors of sleep disturbance and determine the relationship between sleep quality and cardiovascular damage in Chinese patients with pre-dialysis CKD.MethodsA total of 427 pre-dialysis CKD patients (mean age = 39 ± 15 years, 260 male/167 female) were recruited in this study. The demographics and clinical correlates were collected. The sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI), whereas the cardiovascular damage indicators (the Early/late diastolic peak flow velocity (E/A) ratio and left ventricular mass index (LVMI)) were determined by an echocardiographic examination.ResultsOf the CKD patients, 77.8% were poor sleepers as defined by a PSQI score > 5. Median estimated glomerular filtration rate (eGFR) was 69.4(15.8-110.9) ml/min/1.73 m2. Logistic regression analysis revealed that left ventricular hypertrophy (LVH) was independently associated with the PSQI score (OR = 1.092, 95% CI = 1.011-1.179, p = 0.025), after adjustment for age, sex and clinical systolic blood pressure, diastolic blood pressure, Phosphate, Intact parathyroid hormone (iPTH), Hemoglobin and eGFR. The linear regression analysis showed that the E/A ratios were independently associated with the PSQI score (β = -0.115, P = 0.028) after adjustment for a series of potential confounding factors.ConclusionsPoor sleep quality, which is commonly found in pre-dialysis CKD patients, is an independent factor associated with cardiovascular damage in CKD patients. Our finding implies that the association between poor sleep and CVD might be mediated by cardiac remodeling.

Use of fetal echocardiography for characterization of fetal cardiac structure in women with normal pregnancies and gestational diabetes mellitus.

To assess fetal cardiac structure and function and to evaluate the efficacy of routine fetal echocardiography for detection of fetal cardiac abnormalities in women with normal pregnancies and those with gestational diabetes mellitus. In this prospective study, we studied fetal cardiac structure and function in 294 uncomplicated singleton pregnancies and 302 pregnancies complicated by gestational diabetes. Fetal echocardiography (2-dimensional sonography and pulsed wave Doppler imaging) was used to assess functional parameters and to detect any cardiac structural abnormality. Data from clinical and echocardiographic evaluations of neonates at birth and 3 months were obtained to confirm the antenatal findings. The mean maternal age ± SD was 28.9 ± 5.0 years in the diabetes group and was comparable to that of women with normal pregnancies. The mean hemoglobin A1c value was 6.3%, and the mean body mass index was 28.0 kg/m(2). The systolic function as assessed by the ejection fraction increased significantly in the diabetes group compared to the normal pregnancy group independent of glycemic control (P < .001). The pulsed wave parameters (early diastolic peak flow velocity and early-to-late diastolic peak flow velocity ratio) were significantly different between the groups (P < .001). The interventricular septum and fetal ventricular wall thicknesses were significantly increased in the presence of gestational diabetes (P < .001). No major fetal cardiac structural anomaly was detected in either group. On follow-up after delivery, all neonates were assessed clinically and by transthoracic echocardiography to rule out congenital defects. In our study, significant increases in the interventricular septum and ventricular wall thicknesses were detected in the presence of gestational diabetes mellitus. Interestingly, none of the neonates of pregnant women with gestational diabetes were found to have echocardiographic evidence of congenital heart disease.

Effect of Rosuvastatin on Coronary Flow Reserve in Patients With Systemic Hypertension

Although statins reduce cardiac events in hypertensive patients with cardiovascular risk factors, the effect of statins on coronary flow reserve (CFR) has not been examined. We tried to examine the effect of rosuvastatin on CFR in hypertensive patients at cardiovascular risk. CFR was studied in 56 hypertensive patients (40 men, 61 ± 9 years) with cardiovascular risk factors and without coronary artery disease in a prospective clinical trial. Using Doppler echocardiography, coronary flow velocity in the distal left anterior descending artery was recorded at baseline and during intravenous adenosine infusion, and CFR was defined as the ratio of hyperemic to basal average peak diastolic flow velocity. The primary efficacy measure was defined as the change in CFR after rosuvastatin therapy for 12 months. CFR was measured successfully in 55 of 56 enrolled patients (98%). CFR was 3.16 ± 0.44 at baseline and negatively correlated with age (R = -0.30, p = 0.025). All patients continued rosuvastatin 10 mg/day without any serious adverse events. After rosuvastatin therapy, serum total cholesterol, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein significantly decreased from 222 ± 18 to 142 ± 20 mg/dl, 148 ± 21 to 85 ± 18 mg/dl, and 1.7 ± 2.9 to 1.2 ± 3.1 mg/L, respectively (all p <0.01). CFR significantly increased from 3.16 ± 0.44 to 3.31 ± 0.42 (p <0.001). The change in CFR correlated with the change in low-density lipoprotein cholesterol (R = -0.28, p = 0.040) but not with the change in high-sensitivity C-reactive protein. In conclusion, CFR was significantly improved after 12 months of rosuvastatin therapy in hypertensive patients at cardiovascular risk and average levels of serum cholesterol.

Effects of Paclitaxel and Carboplatin combination on mechanical myocardial and microvascular functions: a transthoracic Doppler echocardiography and two-dimensional strain imaging study.

Paclitaxel and carboplatin are frequently used chemotherapy drugs in the treatment of gynecologic malignancies. Little is known about their effects on left ventricular mechanical and coronary microvascular functions. Thirty consecutive patients were prospectively enrolled. Patients underwent transthoracic echocardiography (TTE) before and after chemotherapy, to evaluate left ventricular mechanical functions and coronary flow reserve (CFR). A comprehensive TTE, tissue Doppler and two-dimensional (2D) strain imaging were performed and coronary flow velocity was measured at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak flow velocities. Mitral annular velocities by tissue Doppler, peak strain, and systolic strain rate by velocity vector imaging (VVI) were measured. Baseline measurements were compared with healthy controls (n = 26). No patient developed heart failure (HF) symptoms, no significant change occurred in left ventricular ejection fraction or cardiac output and no significant difference was observed in CFR after chemotherapy. Baseline mean longitudinal peak strain and systolic stain rate were similar between patients and controls: -17.5 ± 2.6% versus -17.6 ± 2.2% (P = NS) and -1.04 ± 0.14/sec versus -1.05 ± 0.12/sec (P = NS). Peak strain and systolic strain rate decreased significantly after chemotherapy (from -17.5 ± 2.6% to -16.2 ± 2.5%, P < 0.02; and from -1.05 ± 0.12/sec to -0.96 ± 0.11/sec, P = 0.01, respectively). However, mean longitudinal velocity did not change significantly. Paclitaxel and carboplatin combination did not impair CFR; however, this chemotherapy combination could induce subtle impairment in myocardial mechanical function which can be detected by advanced deformation imaging techniques rather than by tissue Doppler imaging or conventional 2D and Doppler echocardiography.

Coronary artery occlusions diagnosed by transthoracic Doppler

BackgroundOur aim was to assess whether anterograde flow velocities in septal perforating branches could identify an occluded contralateral coronary artery, and to assess the feasibility and accuracy of diagnosing occlusions in the three main coronary arteries by the combined use of several noninvasive parameters indicating collateral flow.MethodsA total of 108 patients scheduled for coronary angiography because of chest pain or acute coronary syndromes were studied using transthoracic Doppler echocardiography.ResultsAnterograde peak diastolic flow velocities (pDV) in septal perforating branches were higher in patients with angiographic occluded contralateral artery compared with corresponding velocities in patients without significant disease in the contralateral artery (0.80 ± 0.31 m/sec versus 0.37 ± 0.13 m/sec, p < 0.001). Receiver operating characteristic curve showed pDV ≥ 0.57 m/sec to be the optimal cutoff value to identify occluded contralateral artery, with a sensitivity of 79% and a specificity of 69%. Demonstration of at least one positive parameter (retrograde flow in main coronary arteries, reversed flow in septal perforating and left circumflex marginal branches, pDV ≥ 0.57 m/sec, or demonstration of other epicardial or intramyocardial collaterals) indicating collateral flow to an occluded main coronary artery had sensitivity, specificity, positive and negative predictive value of 89%, 94%, 63%, and 99%, respectively, for detection of a coronary occlusion. With this combined use of several parameters, 25 of 28 coronary occlusions were identified.ConclusionsBy investigating several parameters indicating collateral flow, we were able to identify most of the main coronary occlusions in the patient cohort. Furthermore, our study demonstrated that coronary artery occlusions may result in complex and diverging coronary pathophysiology depending on which coronary artery segment is occluded and the extent of accompanying coronary artery disease.Trial registrationClinicalTrials.gov number NTC00281346.

The Correlation between Peripheral Leukocyte Telomere Length and Indicators of Cardiovascular Aging

To investigate the relationship between telomere length in peripheral blood white cells and cardiovascular function in a healthy, aging Han Chinese population. In 2012, peripheral blood leukocytes were obtained from 139 healthy individuals in Beijing, China, and telomere restriction fragment (TRF) length was assayed using a digoxigenin-labeled hybridization probe in Southern blot assays. Indicators of cardiovascular function were also evaluated, including electrocardiograms (ECG), (RR, P, PR, QRS, ST and T intervals); blood pressure (BP), (SBP, DBP, PP, PPI); cardiovascular ultrasound (left ventricular ejection fraction, LVEF); mitral early and late diastolic peak flow velocity (MVE and MVA); and lipid indices (TC, TG, HDL, LDL, LCI). The relationships of these cardiovascular indictors to telomere length were evaluated. No correlations were found between telomere length and ECG, BP or lipid indices even after adjustment for age. Correlations were found between TFR length and some cardiovascular ultrasound indictors (D, MVEA, MVEDT, MVES, MVEL, MVEI, IMT), but these were not seen after adjusting for age. We did not find that leukocyte TFR length was associated with cardiovascular ultrasound indictors, ECG, BP, or lipid indices in this population of healthy Han Chinese individuals. Telomere length may serve as a genetic factor in biological aging.

Coronary flow dynamics in children after repair of Tetralogy of Fallot

ObjectivesTo assess the possible effect of a stiff right ventricle on the coronary flow (CF) in patients with post-operative Tetralogy of Fallot (TOF). BackgroundRight ventricular restrictive physiology i.e. forward flow during atrial contraction (RVRP), is characteristic to many patients with post-operative TOF. MethodsA total of 34 patients with TOF anatomically corrected through transatrial repair were included. Coronary flow parameters were registered with transthoracic Doppler echocardiography from posterior descending (PDCA) and left anterior descending (LAD) coronary arteries in the same patient in 24/34 (71%) patients. Twenty age-matched healthy children were used as controls. Cardiac magnetic resonance (CMR) imaging was used to detect myocardial fibrosis, RV volume, and RVRP. ResultsThe mean age at investigation was 10.2±2.8years. RV end diastolic and end systolic volumes indexed for BSA were larger in patients with RVRP (p=0.002 and 0.008 respectively). Peak flow velocity in diastole and flow velocity time integral was increased in patients compared to controls. They were increased in the LAD in patients with fibrosis of RV (n=11) compared to patients without fibrosis (n=9) (p=0.01 and 0.047 respectively). LAD coronary flow was especially increased in patients with RVRP (n=9) as compared with those without (n=11), (p=0.006). ConclusionsPatients at mid-term followup after correction of TOF show increase of coronary flow. This increase is more pronounced in patients with fibrosis and RVRP of the RV.

Circulating N-terminal brain natriuretic peptide and cardiac function in response to acute systemic hypoxia in healthy humans.

BackgroundAs it remains unclear whether hypoxia of cardiomyocytes could trigger the release of brain natriuretic peptide (BNP) in humans, we investigated whether breathing normobaric hypoxic gas mixture increases the circulating NT-proBNP in healthy male subjects.MethodsTen healthy young men (age 29 ± 5 yrs, BMI 24.7 ± 2.8 kg/m2) breathed normobaric hypoxic gas mixture (11% O2/89% N2) for one hour. Venous blood samples were obtained immediately before, during, and 2 and 24 hours after hypoxic exposure. Cardiac function and flow velocity profile in the middle left anterior descending coronary artery (LAD) were measured by Doppler echocardiography.ResultsArterial oxygen saturation decreased steadily from baseline value of 99 ± 1% after the initiation hypoxia challenge and reached steady-state level of 73 ± 6% within 20–30 minutes. Cardiac output increased from 6.0 ± 1.2 to 8.1 ± 1.6 L/min and ejection fraction from 67 ± 4% to 75 ± 6% (both p < 0.001). Peak diastolic flow velocity in the LAD increased from 0.16 ± 0.04 to 0.28 ± 0.07 m/s, while its diameter remained unchanged. In the whole study group, NT-proBNP was similar to baseline (60 ± 32 pmol/ml) at all time points. However, at 24 h, concentration of NT-proBNP was higher (34 ± 18%) in five subjects and lower (17 ± 17%), p = 0.002 between the groups) in five subjects than at baseline.ConclusionIn conclusion, there is no consistent increase in circulating NT-proBNP in response to breathing severely hypoxic normobaric gas mixture in healthy humans, a possible reason being that the oxygen flux to cardiac myocytes does not decrease because of increased coronary blood flow. However, the divergent individual responses as well as responses in different cardiac diseases warrant further investigations.

Influence of Comorbid Cardiovascular Risk Factors on Left Atrial-Left Ventricular Interaction in Asymptomatic Patients

Previous studies have examined the negative impacts of individual cardiovascular risk (CVR) factors on left atrial (LA)-left ventricular (LV) interaction, whereas the combined effects of these risk factors are insufficiently elucidated. We studied 176 asymptomatic patients with CVR factors and age-matched 50 healthy individuals by conventional and 2-dimensional speckle-tracking echocardiography. The patients were classified into 2 groups according to the number of CVR factors: one risk factor (single) group (n = 79) and 2 or more risk factors (comorbid) group (n = 97). The peak early diastolic transmitral flow velocity (E)/peak early diastolic mitral annular motion velocity (e')/peak systolic LA strain (S-LAs) was used as a surrogate for LA stiffness during ventricular systole. The E/e'/S-LAs was greatest in the comorbid group. The peak systolic LV circumferential and radial strains, peak early diastolic LV radial strain rate, and peak early diastolic LA strain and strain rate were lower in the comorbid group than in the single group. Multivariate regression analysis identified age, body mass index, systolic blood pressure, end-systolic LV diameter, peak systolic mitral annular motion velocity (s'), and peak systolic LV radial strain in the comorbid group, and peak atrial systolic transmitral fl ow velocity and s' in the single group, as independent predictors of E/e'/S-LAs. Subtle LA and LV dysfunction with individual CVR factors were more aggravated with the comorbid conditions in asymptomatic patients.

Early changes in myocardial repolarization and coronary perfusion after cardiopulmonary bypass surgery for ASD repair in children

BackgroundIn adults, impaired myocardial repolarization and increased risk of arrhythmia are known consequences of open heart surgery. Little is known, however, about post-operative consequences of cardiopulmonary bypass surgery in children. The aim of this study was to assess ventricular repolarization and coronary perfusion after bypass surgery for atrial septal defect (ASD) repair in children.MethodsTwelve patients with ASD were assessed one day before and 5–6 days after ASD repair. Myocardial repolarization (corrected QT interval, QTc, QT dispersion, QTd, and PQ interval) was determined on 12-lead electrocardiograms. Coronary flow in proximal left anterior descending artery (peak flow velocity in diastole, PFVd) was assessed by transthoracic Doppler echocardiography.ResultsTen of the 12 (83%) children had normal myocardial repolarization before and after surgery. After surgery, QTc increased 1-9% in 5 (42%) patients, decreased 2-11% in 5 (42%) patients and did not change in 2 (16%) patients. Post-op QTc positively correlated with bypass time (R=0.686, p=0.014) and changes in PFVd (R=0.741, p=0.006). After surgery, QTd increased 33-67% in 4 (33%) patients, decreased 25-50% in 6 patients (50%) and did not change in 2 (16%) patients. After surgery, PQ interval increased 5-30% in 4 (33%) patients, decreased 4-29% in 6 (50%) patients and did not change in 1 (8%) patient. Post-op PQ positively correlated with bypass time (R=0.636, p=0.027). As previously reported, PFVd significantly increased after surgery (p<0.001).ConclusionsChanges in QTc, PQ and PFVd are common in young children undergoing surgery for ASD repair. Post-op QTc significantly correlates with bypass time, suggesting prolonged cardiopulmonary bypass may impair ventricular repolarization. Post-op QTc significantly correlates with PFVd changes, suggesting increased coronary flow may also impair ventricular repolarization. The clinical significance and reversibility of these alternations require further investigations.

Evaluation of coronary microvascular function and nitric oxide synthase intron 4a/b polymorphism in patients with coronary slow flow

Slow coronary flow (SCF) is reported to be associated with increased risk of cardiovascular disease. We have used coronary flow reserve measurement by transthoracic Doppler echocardiography to determine coronary microvascular function in patients with SCF and to determine whether the intron 4a/b polymorphism of the eNOS gene influences coronary endothelial function. Overall, 96 patients with SCF and 79 controls were enrolled in the study. Coronary flow was quantified according to the thrombolysis in myocardial infarction (TIMI) frame count (TFC) on angiogram. Coronary diastolic peak flow velocities (DPFV) were measured with color Doppler flow mapping at baseline and after dipyridamole infusion. Coronary flow reserve was calculated as the ratio of hyperemic to baseline DPFV. The eNOS 4a/b polymorphism was detected by PCR. Patients with diabetes were excluded from the study. The SCF group was comparable to the control group in terms of demographic and clinical characteristics, except for hemoglobin and HDL-cholesterol levels, TFC of the left anterior descending artery, the circumflex artery, and the right coronary artery; the mean TFC was higher in the SCF group. Hyperemic DPFV and the hyperemic/baseline DPFV ratio were significantly lower in the SCF group when compared with the control group. However, baseline DPFV were similar in both groups. The number of patients with eNOS4 a/a and eNOS4 a/b phenotypes was statistically higher in SCF groups. The frequency of allele 'a' of the eNOS4 gene was also statistically higher in the SCF group. When patients were grouped according to the presence or absence of allele 'a' of the eNOS4 gene, statistically significant differences were found in the TFC of the left anterior descending artery, the circumflex artery; mean TFC; baseline DPFV; and hyperemic/baseline DPFV. Univariate analysis in which eNOS4 b/b was used as the referent group showed that the presence of allele 'a' of the eNOS4 gene significantly predicted SCF (odds ratio: 2.79, 95% confidence interval: 1.32-5.89; P=0.007). In multivariate analysis using a model adjusted for variables with a P value lower than 0.10 in univariate analyses, the presence of allele 'a' of the eNOS4 gene was found to be an independent predictor of SCF (odds ratio: 3.22, 95% confidence interval: 1.28-8.82; P=0.013). The presence of allele 'a' may be a risk factor for microvascular endothelial dysfunction and higher TFCs in SCF patients.

Flow in the Left Anterior Descending Coronary Artery in Patients With Migraine Headache

Migraine is a common neurovascular disorder characterized by attacks of severe headache, autonomic and neurologic symptoms. Migraine can affect many systems in the body, yet its effects on cardiovascular system are unclear. We hypothesized that migraine and coronary microvascular angina may be manifestations of a common systemic microvascular dysfunction and clinically associated. Forty patients with migraine and 35 healthy volunteers were included into the study. Using transthoracic Doppler echocardiography, coronary flow was visualized in the middle or distal part of the left anterior descending artery. Coronary diastolic peak flow velocities were measured with pulse wave Doppler at baseline and after dipyridamole infusion (0.56 mg/kg/4 min). Coronary flow reserve of <2 was considered normal. In addition, thorough 2-dimensional and Doppler echocardiographic examinations were also performed. Fifty-two women and 23 men were included. Coronary flow reserve was significantly lesser in the migraine group than in the control group (1.99 ± 0.3 vs 2.90 ± 0.5, p <0.05). In addition, mitral annular velocities were lower and the ratio of early mitral inflow velocity to early mitral annular velocity (E/E' lateral and E/E' septal) was higher in migraineurs than in the control group (p <0.05 for all), indicating diastolic function abnormalities in the migraine group. In conclusion, these findings suggest that there is an association between coronary microvascular dysfunction and migraine independently of the metabolic state of the patients. A common pathophysiologic pathway of impaired endothelial vasodilatation, vasomotor dysfunction, and increased systemic inflammatory factors may play a role in these 2 clinical conditions and could be the underlying cause of subclinical systolic and diastolic left ventricular dysfunction in migraineurs.

GW24-e2951 Gender-Specific Relationship between Carotid Intema-media Thickness and Cardiac Diastolic function in a Healthy Chinese Population

ObjectivesTo identify gender difference in the associations between carotid intema-media thicknesss (CIMT) and cardiac diastolic function in healthy Chinese individuals.MethodsWe examined 852 healthy participants (aged 30-98 years, 46% men) in...

Coronary Microvascular function, Peripheral Endothelial Function and Carotid IMT in beta-thalassemia minor

Higher prevalence of cardiovascular disease in Thalassemia patients have been known. Potential mechanisms are enhanced platelet activation, LDL oxidation, macrophage activation, and increased nitric oxide destruction. We have investigated coronary flow reserve (CFR), brachial artery flow mediated dilation (FMD) and Carotid intima-media thickness (IMT) in patients with Beta thalessemia minor (BTM). MethodsForty patients with BTM and 35 healthy control subjects were included. In all subjects CFR, brachial artery FMD, carotid artery IMT were measured. ResultsCFR measurements: Coronary baseline diastolic peak flow velocity (DPFV) of left anterior descending coronary artery (LAD) was significantly higher in the BTM group (23.8±3.9 vs. 22.1±3.0, P=0.04). However, hyperemic DPFV was significantly lower (61.1±13.0 vs. 68.2±14.2, P=0.02), and CFR was significantly lower (2.57±0.46 vs. 3.07±0.48, P<0.0001) in the BTM group than that in the control group.Brachial artery FMD and carotid IMT measurements: Percent FMD measurements were significantly lower in the BTM group than that in the controls (6.22±4.29 vs. 8.10±4.00, P=0.01). Carotid IMT measurements were significantly but slightly higher in the BTM group than that in the controls (0.57±0.07 vs. 0.54±0.04, P=0.04). ConclusionCFR reflecting coronary microvascular function and brachial artery FMD are decreased, and carotid IMT is increased in patients with BTM.

Impaired coronary flow reserve is associated with increased echocardiographic epicardial fat thickness in metabolic syndrome patients

Metabolic syndrome (MetS) is a strong predictor of cardiovascular events and coronary flow reserve (CFR), an indicator of microvascular function, has been found to be impaired in MetS. Epicardial fat thickness (EFT) reflects visceral adiposity and is considered an important cardiometabolic marker. In this study, we aimed to examine the presence of an association between CFR and EFT in MetS patients. Forty-six MetS patients (25 men, mean age 47.3±6.6 years) and 44 age-matched and sex-matched controls (24 men, mean age 46.0±6.1 years) were prospectively studied. Both CFR and EFT were measured by transthoracic echocardiography. Peak diastolic coronary flow velocities were measured in the left anterior descending artery by pulsed wave Doppler at the baseline and after adenosine infusion, and CFR was calculated as the ratio of hyperemic to baseline velocities. The waist circumference, total and low-density lipoprotein-cholesterol, fasting glucose, triglycerides, systolic and diastolic blood pressures, and high sensitive C-reactive protein were significantly higher in MetS patients. The mean EFT was significantly higher in MetS patients compared with the controls (8.7±0.2 vs. 4.8±0.1 mm, P<0.001); however, CFR was significantly lower in MetS patients (2.3±0.2 vs. 2.7±0.2, P<0.001). CFR was correlated significantly with BMI, waist circumference, high-density lipoprotein-cholesterol, triglycerides, fasting glucose, high sensitive C-reactive protein, and EFT. In regression analysis, MetS itself and EFT were found to be independent predictors of impaired CFR. CFR is impaired in MetS patients. MetS itself and increased EFT are associated independently with coronary microvascular dysfunction and EFT is a predictor of worse CFR even after accounting for the presence or absence of the MetS.