Left atrial booster-pump function as a predictive parameter for atrial fibrillation in patients with severely dilated left atrium.

Background: Left atrial (LA) dimension ≥50 mm had approximately four times the risk of developing atrial fibrillation (AF). The aim of this study was to investigate whether the application of clinical and echocardiographic parameters could differentiate between the patients having severely dilated left atrium with and without AF. Methods: This retrospective cross-sectional study enrolled consecutive patients with LA dimension ≥50 mm and divided them into three groups: no AF (no-AF), paroxysmal AF (PAF) and non-paroxysmal AF (non-PAF) groups. For PAF and non-PAF groups, all patients underwent radiofrequency ablation, and the echocardiographic parameters were obtained on the next day after ablation. Results: Our study population comprised 160 patients, including 80, 53, and 27 patients in the non-AF, PAF and non-PAF groups, respectively. The no-AF group had a significantly higher body mass index (kg/m2) (29.31±6.27, 27.58±4.12 and 26.57±2.81, P=0.01), and a higher prevalence of diabetes mellitus (DM) [31 (38.80%), 13 (25.00%) and 4 (14.80%), P=0.01] and hypertension [67 (83.80%), 34 (65.40%), and 19 (70.40%), P=0.04], but a lower prevalence of rheumatic heart disease (RHD) [3 (3.80%), 6 (11.50%) and 5 (18.50%), P=0.02] and sick sinus syndrome [0 (0.00%), 6 (11.50%) and 4 (14.80%), P=0.045]. Echocardiographic studies showed that the non-AF group had significantly smaller LA minimal volume index (24.89±9.74, 34.06±19.38 and 42.83±17.44 mL/m2, P<0.01), higher LA emptying fraction (51.99%±13.97%, 38.40%±15.96% and 33.89%±10.73%, P<0.01), longitudinal strain (23.87%±7.72%, 17.11%±8.52% and 12.38%±4.28%, P<0.01) and strain rate than the AF groups. The multivariate analysis showed that the late diastolic component of LA strain rate was the only independent factor associated with the presence of AF (odds ratio, 21.69; 95% CI, 9.77-48.13, P<0.01). Conclusions: LA function plays an important role in the absence of AF in patients with LA dimension ≥50 mm; the late diastolic component of LA strain rate was the only independent variable on multivariate analysis.

P wave duration ≥150 ms predicts poor left atrial function and ablation outcomes in non-paroxysmal atrial fibrillation.

BACKGROUND: It remains unknown whether P wave duration (PWD) ≥ 150 ms measured after extensive radiofrequency catheter ablation (RFCA) can identify non-paroxysmal atrial fibrillation (non-PAF) patients at increased risk of atrial tachyarrhythmia recurrence. We investigated the predicting power of PWD and its association with left atrial (LA) reverse remodeling in patients with non-PAF undergoing pulmonary vein isolation with LA linear ablation. METHODS: We retrospectively evaluated 136 patients who underwent RFCA for drug-refractory non-PAF. Electroanatomic mapping was acquired during AF. Low-voltage area (LVA) was defined as an area with bipolar voltage ≤0.5 mV. Electrocardiography and echocardiography were performed during sinus rhythm 1 day and 3 months after RFCA. PWD was measured using amplified 12­lead electrocardiography. Prolonged PWD was defined as maximum PWD ≥ 150 ms. RESULTS: Over a mean follow-up duration of 48 ± 35 months, 28 patients experienced atrial tachyarrhythmia recurrence. PWD was positively correlated with LVA (r = 0.527, p < 0.001) and inversely correlated with LA emptying fraction (r = -0.399, p < 0.001). PWD was shortened and LA emptying fraction (LAEF) was increased in patients without atrial tachyarrhythmia recurrence during follow-up. Atrial tachyarrhythmia-free survival was significantly more likely in patients without a prolonged PWD (83.5% vs 60.7%, p = 0.002). Multivariate analysis showed that LAEF and PWD were independent predictors of atrial tachyarrhythmia recurrence. CONCLUSIONS: PWD ≥ 150 ms measured after RFCA can identify patients with non-PAF at increased risk of atrial tachyarrhythmia recurrence. PWD is correlated with LVA and LAEF and reflects LA reverse remodeling.

Atrial fibrillation and associated outcomes in patients with peritoneal dialysis and hemodialysis: a 14-year nationwide population-based study.

BACKGROUND: Patients with end-stage renal disease (ESRD) undergoing dialysis have increased risks of atrial fibrillation (AF). OBJECTIVE: To investigate dialysis-related incident AF and associated outcomes. METHODS: Patients with dialysis were retrieved using data from Taiwan National Health Insurance Research Database during 2001-2013. Patients were separated into peritoneal dialysis (PD) and hemodialysis (HD) according to their initial modality. Primary outcome was new-onset AF. Secondary outcomes were AF-associated ischemic stroke (IS)/systemic embolism (SE) and hemorrhagic stroke. RESULTS: A total of 158,910 dialytic patients were retrieved. After exclusion criteria, a total of 117,023 patients with ESRD undergoing dialysis were separated into 12,659 patients on PD and 104,364 patients on HD. There were 458 PD patients with subsequent development of AF, and 6216 HD patients with subsequent development of AF. At end of follow-up, patients on PD and HD had AF incidence densities of 7.8 and 8.8 events per 1000 person-years, the SHR of PD versus HD was 0.83 (95% CI 0.73-0.94). The SHR of PD versus HD was 1.07 (95% CI 0.80-1.44) for IS/SE and the SHR of PD versus HD was 0.34 (95% CI 0.13-0.90) for hemorrhagic stroke. CONCLUSION: In patients with ESRD undergoing dialysis, PD had lowered risks of new onset of AF compared to HD. Subsequently, these AF patients in PD group had comparable incidence of ischemic stroke but decreased incidence of hemorrhagic stroke compared to AF patients in HD group. PD could be the most suitable modality in patients at risk for the onset of AF.

Sport disciplines and cardiac remodeling in elite university athletes competing in 2017 Taipei Summer Universiade.

Cardiac remodeling is common in the athletes. Little data is available regarding the cardiac remodeling on the recently proposed 4 sport disciplines among the elite university athletes.A total of 7639 athletes participated in the 2017 Taipei Summer Universiade. Cardiac evaluation via history, ECG, and echocardiography were performed in 826 athletes who signed up for Check Up Your Heart. Athletes were grouped into one of 4 sport disciplines Skill, Power, Mixed, and Endurance.After excluding 66 participants with missing demographic data, 13 missing echocardiographic data, and 24 inadequate echocardiographic images, a total number of 723 university athletes (mean age 23 ±â€Š3 years, 419 males) from 99 countries engaging in 25 different sporting events were analyzed. Electrocardiograms showed that Endurance group had a slower heart rate and higher percentage of left ventricular (LV) hypertrophy (39%). Echocardiograms showed there were significant differences in LV mass index (P < .001), LV geometry (P < .001), left atrial (LA) dilatation (P = .026), right ventricular (RV) dilatation (P < .001), right atrial (RA) dilatation (P < .0001), and tricuspid annular plane systolic excurse (P = .006). LV ejection fraction, LV strain, RV strain, and LV diastolic function showed no difference in 4 sport disciplines.Eccentric LV hypertrophy was the most common type of cardiac remodeling in the university athletes participated in 2017 Taipei Summer Universiade. Adaptive changes in chamber size were more commonly seen in Endurance sport. RA dilatation was the most sensitive to hemodynamic demand, followed by RV dilatation, LA dilatation, and LV dilatation.

A Novel Approach for Predicting Atrial Fibrillation Recurrence After Ablation Using Deep Convolutional Neural Networks by Assessing Left Atrial Curved M-Mode Speckle-Tracking Images.

Aims: Curved M-mode images of global strain (GS) and strain rate (GSR) provide sufficiently detailed spatiotemporal information of deformation mechanics. This study investigated whether a deep convolutional neural network (CNN) could accurately classify these images in patients with atrial fibrillation (AF) who underwent radiofrequency catheter ablation (RFCA) with different outcomes. Methods and Results: We retrospectively evaluated 606 consecutive patients who underwent RFCA for drug-refractory AF. Patients were divided into AF-free (n = 443) and AF-recurrent (n = 163) groups. Transthoracic echocardiography was performed within 24 h after RFCA. Left atrial curved M-mode speckle-tracking images were acquired from randomly selected 163 patients in AF-free group and 163 patients in AF-recurrent group as the dataset for deep CNN modeling. We used the ReLu activation function and repeatedly performed CNN model for 32 times to evaluate the stability of hyperparameters. Logistic regression models with the left atrial dimension, emptying fraction, and peak systolic GS as predictor variables were used for comparisons. Images from the apical 2-chamber (2-C) and 4-chamber (4-C) views had distinct features, leading to different CNN performance between settings; of them, the "4-C GS+4-C GSR" setting provided the highest performance index values. All four predictor variables used for logistic regression modeling were significant; however, none of them, individually or in any combined form, could outperform the optimal CNN model. Conclusion: The novel approach using deep CNNs for learning features of left atrial curved M-mode speckle-tracking images seems to be optimal for classifying outcome status after AF ablation.

Outcomes of patients with hypertrophic cardiomyopathy and acute myocardial infarction: a propensity score-matched, 15-year nationwide population-based study in Asia.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) entails thickening of the myocardium and an increased risk of ischaemia. However, the prognosis of patients with HCM with acute myocardial infarction (AMI) is incompletely understood. METHODS: Medical information was retrieved from the Taiwan National Health Insurance Research Database in 1997-2011. The exclusion criteria were patients <18 years old, and history of AMI, coronary intervention, aortic valve disease, disease of the pericardium, heart surgery, device implantation, venous thromboembolism, cardiac transplant, congenital heart disease and end-stage renal disease on dialysis. Patients with HCM with AMI were compared with propensity score (PS)-matched patients with AMI without HCM. The primary endpoints were in-hospital and 1-year cardiovascular events. RESULTS: In total, 201 166 patients were admitted for AMI. There were 177 058 patients with new-onset AMI, 257 with HCM and 176 801 without HCM after exclusion criteria. Using 1:4 PS matching, the study population consisted of patients with AMI, 257 with HCM and 1028 without HCM. Patients with AMI with HCM received significantly less coronary intervention (OR=0.46; 95% CI 0.32 to 0.65; p<0.001), coronary intervention with stenting (OR=0.33; 95% CI 0.20 to 0.57; p<0.001) and coronary artery bypass graft surgery (OR=0.22; 95% CI 0.05 to 0.90; p=0.036), and fewer episodes of shock (OR=0.64; 95% CI 0.48 to 0.86; p=0.003) and in-hospital death (OR=0.46; 95% CI 0.30 to 0.70; p<0.001), compared with patients with AMI without HCM. Specifically, for patients with HCM with AMI, AMI occurred predominantly (82.5%) in the form of ischaemia without requiring coronary stenting. Patients with AMI with HCM had significantly better survival than patients without HCM (HR=0.66; 95% CI 0.51 to 0.85; p=0.001) during the 1-year follow-up. CONCLUSIONS: This is the first PS-matched study to compare the prognosis of patients with AMI with and without HCM. Compared with patients with AMI without HCM, patients with HCM had significantly better in-hospital and within 1-year outcomes.

Prognostic value of area of calcified aortic valve by 2-dimensional echocardiography in asymptomatic severe aortic stenosis patients with preserved left ventricular ejection fraction.

We hypothesized that area of calcified aortic valve (ACAV) measured by 2D echocardiography (2DE) can predict future cardiovascular events in asymptomatic severe aortic stenosis (AS).Multidetector computed tomography determined aortic valve calcification load is strongly associated with AS severity but has risks for radiation exposure. Quantification of ACAV by transthoracic 2DE is simple and convenient but its clinical utility has not been extensively studied.We measured ACAV in 124 asymptomatic severe AS patients (80 ±â€Š9 years, 45 males) with preserved left ventricular ejection fraction. ACAV was measured by planimetry from 2D zoomed long axis view of the AV at end-diastole. Patients were followed to record cardiac death (CD) and major adverse cardiovascular events (MACEs).During a median follow-up of 232 days, 17 patients had MACE, including 8 CD. ACAV was significantly larger in patients with event compared to those without (1.14 ±â€Š0.35 cm vs 0.87 ±â€Š0.34 cm, P=.0032). Using receiver operating characteristics derived ACAV of 0.79 cm as cutoff value, Kaplan-Meyer analysis showed it could discriminate high-risk group from low-risk group for future CD (P=.0223, χ = 5.22) and MACE (P = .0054, χ = 7.74).2DE determined ACAV is straightforward and has potential to predict future cardiac events in asymptomatic severe AS patients.

Left atrial emptying fraction predicts recurrence of atrial fibrillation after radiofrequency catheter ablation.

BACKGROUND: Compared with left atrial (LA) dimension, LA emptying fraction (LAEF) has received less emphasis as a predictor of atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA). In addition, patients experiencing post-RFCA AF recurrence may respond to previously ineffective antiarrhythmic drugs (AADs). Classifying these patients into a third RFCA outcome category is recommended. OBJECTIVE: To identify predictors of RFCA outcome classified into three categories, and to build proportional odds logistic regression models for clinical applicability to predict AF recurrence. METHODS: Data were retrospectively collected from 483 consecutive patients with drug-refractory AF undergoing RFCA (328 men; age 58.4 ± 11.5 years; 383 paroxysmal). Patients were classified into 3 groups based on the last RFCA outcome: group 1, free from AF without AADs; group 2, free from AF with AADs; and group 3, recurrence of AADs-refractory atrial tachyarrhythmia. RESULTS: After a mean follow-up duration of 64.5 ± 43.2 months and mean ablation procedure number of 1.37 ± 0.68, the RFCA outcome showed 76.0%, 9.5% and 14.5% of patients in groups 1, 2, and 3, respectively. In multivariate analysis, LAEF was the most stable and important predictor of AF recurrence, followed by body mass index, stroke, AF duration, mitral regurgitation, and LA linear ablation. For patients undergoing repeat RFCA, LAEF was the only independent predictor (cutoffs: 43% and 35% for groups 1 and 3, respectively). CONCLUSION: LAEF provides optimal prognostic information regarding the risk stratification of AF patients undergoing RFCA.

Comparison of cardiovascular outcomes and all-cause mortality in patients with chronic hepatitis B and C: A 13-year nationwide population-based study in Asia.

BACKGROUND AND AIMS: Viral hepatitis infection has been linked to increased atherosclerosis. We therefore investigated cardiovascular outcomes in patients with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. METHODS: Electronic medical records during 2000-2012 were retrieved from the Taiwan National Health Insurance Research Database. Exclusion criteria were age <18, history of coexisting HBV and HCV infection, acute coronary syndrome, coronary intervention, venous thromboembolism, peripheral artery disease, stroke, major or gastrointestinal bleeding, malignancy, and a follow-up period <180 days. Patients with HBV and HCV infection were propensity-matched then compared for outcomes. Primary outcomes were cardiovascular events at the 1-year follow-up, 3-year follow-up, 5-year follow-up, and at the end of follow-up. RESULTS: 41,554 patients with diagnosis of HBV or HCV were retrieved from 2000 to 2012. After exclusion criteria, 31,943 patients were eligible for analysis and propensity score matched. The study population consisted of 6030 patients with HBV infection and 6030 patients with HCV infection. Risk of composite arterial events (acute coronary syndrome, peripheral artery disease, and acute ischemic stroke) was significantly higher in patients with HCV infection compared with patients with HBV infection (p = 0.012 at 5-year follow-up and p = 0.003 at the end of follow-up). All-cause mortality was significantly higher in patients with HCV infection compared with patients with HBV infection (p < 0.001 at 3-year follow-up, 5-year follow-up, and at the end of follow-up). CONCLUSIONS: In patients with chronic viral hepatitis, subjects with HCV infection had a significantly higher risk of composite arterial events and all-cause mortality compared with those with HBV infection.

Clinical outcomes of peripartum cardiomyopathy: a 15-year nationwide population-based study in Asia.

Peripartum cardiomyopathy (PPCM) is the development of heart failure during late pregnancy to months postpartum with potential fatal outcome. However, the disease is not well-studied in Asia.We aimed to investigate the epidemiology and clinical outcomes of PPCM in Taiwan.Electronic medical records were retrieved from Taiwan National Health Insurance Research Database from 1997 to 2011. Patients with PPCM were separated into 3 groups based on the timing of diagnosis. Early: PPCM diagnosed first to ninth month of pregnancy. Traditional: PPCM diagnosed last month of pregnancy till fifth month post-delivery. Late: PPCM diagnosed sixth to twelfth month post-delivery. Primary outcomes defined as cardiac death, all-cause mortality, and major adverse cardiovascular events (MACE) within 1 year.A total of 3,506,081 deliveries during 1997 to 2011 were retrieved and 925 patients with PPCM were identified. Overall incidence of PPCM was 1:3,790 during the 15 years. Early, Traditional, and Late group each had 88, 742, and 95 patients. Cardiac death occurred in 31 patients, all-cause mortality in 72 patients, and MACE in 65 patients. Late group had 2- to 3-fold event rates in cardiac death, all-cause mortality, and MACE compared with Early and Traditional groups. Cumulative incidence showed significant differences for cardiac death (P = .0011), all-cause mortality (P = .0031), and MACE (P = .0014) among 3 groups. Multivariate Cox model showed Late group had significantly worse outcomes after adjusted for clinical variables compared with 2 other groups.Our study is the largest national cohort among Asian countries that showed timing of diagnosis of PPCM had different outcomes. Late diagnosis portended significantly increased morbidity and mortality, even after adjusted for clinical variables.

Prognostic Value of Right Ventricular Ejection Fraction Assessed by Transthoracic 3D Echocardiography.

BACKGROUND: Cardiac magnetic resonance is the gold standard for the evaluation of right ventricular (RV) volumes, but it is impractical to perform in every patient. Although reference values of RV volumes and RV ejection fraction by 3D transthoracic echocardiography (3DTTE) have been established, their prognostic values have not been elucidated yet. We hypothesized that RV ejection fraction measured by 3DTTE (3DRVEF) predicts future cardiovascular events. METHODS AND RESULTS: In protocol 1, we determined the accuracy of RV volumes and RV ejection fraction measurements by 3DTTE against cardiac magnetic resonance in 60 subjects. In protocol 2, 3DRVEF was measured in 446 patients with various cardiovascular diseases. Study subjects were followed up to record cardiac death and major adverse cardiovascular events. In protocol 1, 3DTTE-determined RV end-diastolic volume, end-systolic volume, and RV ejection fraction had good correlations to those by cardiac magnetic resonance (r=0.74-0.90). In protocol 2, 38 cardiac deaths and 88 major adverse cardiovascular events occurred during a median follow-up of 4.1 years. Univariable Cox proportional analysis revealed that 3DRVEF was associated with both cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001). 3DRVEF remained as an independent predictor for cardiac death (P<0.0001) and major adverse cardiovascular event (P<0.0001) even in a stepwise multivariable Cox proportional hazard analysis. Classification and regression-tree analysis demonstrated that 3DRVEF played an important role for risk stratification. CONCLUSIONS: 3DTTE-determined RV ejection fraction was independently associated with cardiac outcomes in patients with diverse backgrounds. 3DRVEF offered incremental value over clinical risk factors and the other echocardiographic parameters including left ventricular systolic and diastolic function for predicting future adverse outcome.

Early Detection of Left Ventricular Diverticulum by Transthoracic Echocardiography.

Left ventricular diverticulum is a very rare entity to be found in adults. Noninvasive echocardiography can offer useful information prior to contrast-enhanced computer tomography or invasive angiography. We evaluated a patient with left ventricular apical diverticulum but complained no symptoms. Transthoracic echocardiography demonstrated a outpouching at left ventricle apex. A 640-slice computed tomography later confirmed the left ventricular diverticulum.

Comparisons of the underlying mechanisms of left atrial remodeling after repeat circumferential pulmonary vein isolation with or without additional left atrial linear ablation in patients with recurrent atrial fibrillation.

BACKGROUND: Radiofrequency catheter ablation (RFCA) is a potentially curative treatment for atrial fibrillation (AF), however, whether or not additional left atrial (LA) linear ablation for recurrent AF adversely affects LA remodeling is unknown. METHODS: Thirty-eight patients experiencing AF recurrence after the 1st circumferential pulmonary vein isolation (CPVI) underwent a repeat RFCA, including 20 and 18 patients receiving a repeat CPVI (group I) or CPVI plus LA linear ablation (group II), respectively. 2-D echocardiography was performed during sinus rhythm within 24h, at 1-m and 6-m after RFCA. Longitudinal strains and strain rate were measured with speckle-tracking echocardiography. The standard deviation of contraction duration was defined as LA mechanical dispersion. RESULTS: One and two patients experienced AF recurrence after the 2nd RFCA in group I and II, respectively (P=NS). The 1st CPVI with AF recurrence did not reduce LA size significantly in two groups. After a repeat CPVI, LA diameter but not LA maximal and minimal volume was significantly reduced in group I; additional LA linear ablation significantly decreased LA diameter, maximal and minimal volume in group II. However, there was no significant difference in LA emptying function, global and segmental LA strain and strain rate among the baseline, 1-m and 6-m follow-up in two groups. RFCA did not significantly increase LA mechanical dispersion regardless of the AF ablation strategies. CONCLUSIONS: In patients with recurrent AF, a successful repeat CPVI with or without additional LA linear ablation reduced LA size without significant deleterious effects on LA function and mechanical dispersion.

Optimized Collection Protocol for Plasma MicroRNA Measurement in Patients with Cardiovascular Disease.

Background. Various microRNAs (miRNAs) are used as markers of acute coronary syndrome, in which heparinization is considered mandatory therapy. Nevertheless, a standard method of handling plasma samples has not been proposed, and the effects of heparin treatment on miRNA detection are rarely discussed. Materials and Method. This study used quantitative polymerase chain reaction (qPCR) analysis to investigate how storage temperature, standby time, hemolysis, and heparin treatment affect miRNA measurement in plasma samples from 25 patients undergoing cardiac catheterization. Results. For most miRNAs, the qPCR results remained consistent during the first 2 hours. The miRNA signals did not significantly differ between samples stored at 4°C before processing and samples stored at room temperature (RT) before processing. miR-451a/miR-23a ratio < 60 indicated < 0.12% hemolysis with 100% sensitivity and 100% specificity. Pretreatment with 0.25 U heparinase I recovered qPCR signals that were reduced by in vivo heparinization. Conclusions. For miRNA measurement, blood samples stored at RT should be processed into plasma within 2 hours after withdrawal and should be pretreated with 0.25 U heparinase I to overcome heparin-attenuated miRNA signals. The miR-451a/miR-23a ratio is a reliable indicator of significant hemolysis.

Cardioprotective Actions of TGFßRI Inhibition Through Stimulating Autocrine/Paracrine of Survivin and Inhibiting Wnt in Cardiac Progenitors.

Heart failure due to myocardial infarction (MI) is a major cause of morbidity and mortality in the world. We found previously that A83-01, a TGFßRI inhibitor, could facilitate cardiac repair in post-MI mice and induce the expansion of a Nkx2.5 + cardiomyoblast population. This study aimed to investigate the key autocrine/paracrine factors regulated by A83-01 in the injured heart and the mechanism of cardioprotection by this molecule. Using a previously described transgenic Nkx2.5 enhancer-green fluorescent protein (GFP) reporter mice, we isolated cardiac progenitor cells (CPC) including Nkx2.5-GFP + (Nkx2.5+), sca1+, and Nkx2.5+/sca1 + cells. A83-01 was found to induce proliferation of these three subpopulations mainly through increasing Birc5 expression in the MEK/ERK-dependent pathway. Survivin, encoded by Birc5, could also directly proliferate Nkx2.5 + cells and enhance cultured cardiomyocytes viability. A83-01 could also reverse the downregulation of Birc5 in postinjured mice hearts (n = 6) to expand CPCs. Moreover, the increased Wnt3a in postinjured hearts could decrease CPCs, which could be reversed by A83-01 via inhibiting Fzd6 and Wnt1-induced signaling protein 1 expressions in CPCs. Next, we used inducible αMHC-cre/mTmG mice to label cardiomyocytes with GFP and nonmyocytes with RFP. We found A83-01 preserved more GFP + myocytes (68.6% ± 3.1% vs. 80.9% ± 3.0%; p < .05, n = 6) and fewer renewed RFP + myocytes (0.026% ± 0.005% vs. 0.062% ± 0.008%; p < .05, n = 6) in parallel with less cardiac fibrosis in isoprenaline-injected mice treated with A83-01. TGFßRI inhibition in an injured adult heart could both stimulate the autocrine/paracrine activity of survivin and inhibit Wnt in CPCs to mediate cardioprotection and improve cardiac function.

Intervendor variability of two-dimensional strain using vendor-specific and vendor-independent software.

BACKGROUND: Although two-dimensional (2D) strain is widely used to assess left ventricular mechanics, the strain values derived from vendor-specific 2D speckle-tracking software are different even for the same subjects and are therefore not interchangeable. The aim of this study was to test the hypothesis that vendor-independent software would produce lower intervendor variability between 2D strain measurements and overcome this limitation. METHODS: Two sets of three apical images were acquired using two of three types of ultrasound machines (GE, Philips, and Toshiba) in 81 healthy volunteers (GE vs Philips in 26 subjects, Philips vs Toshiba in 31 subjects, and GE vs Toshiba in 24 subjects). Two-dimensional global longitudinal strain (GLS) was measured using vendor-specific software and two vendor-independent software packages (TomTec and Epsilon) in each set of apical images, and GLS values were directly compared with one another. RESULTS: The upgrades of vendor-specific software yielded different values of GLS compared with the previous versions of the software. The correlations between the GLS values determined using vendor-specific software exhibited a wide range of r values (r = 0.23, r = 0.42, and r = 0.72), with significant bias, with the exception of one comparison. The vendor-independent software provided modest degrees of correlation (TomTec: r = 0.65, r = 0.65, and r = 0.77; Epsilon: r = 0.65, r = 0.74, and r = 0.77), with limits of agreement (range, ±3% to ±4.5%) that were not negligible. CONCLUSIONS: Although the vendor-independent 2D strain software provided moderate correlations between the GLS values of the ultrasound images obtained from the same subjects using different vendors, relatively large limits of agreement remain a relevant problem. These results suggest that the same ultrasound machine and the same 2D speckle-tracking software should be used for longitudinal analysis of strain values in the same subjects and for cross-sectional studies.

Clinical and angiographic outcomes after intracoronary bare-metal stenting.

BACKGROUND: Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8-17 years) clinical and long-term (3-5 years) angiographic outcomes after intracoronary bare-metal stenting (BMS). METHODS AND RESULTS: From the Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN) registry, a total of 2391 patients with 2966 lesions treated with 3190 BMSs between November 1995 and May 2004 were evaluated. In total, 1898 patients with 2364 lesions, and 699 patients with 861 lesions underwent 6-month and 3- to 5- year angiographic follow-up, respectively. During a mean follow-up period of 149 ± 51 months, 18.6% of the patients died (including 10.8% due to cardiac death), 6.1% developed reinfarction, 16.2% had target lesion revascularization (including 81% of the patients within the first year), 14.5% underwent new lesion stenting (including 72% of the patients after 3 years), 2.4% underwent coronary bypass surgery, and 1.6% had definite stent thrombosis. The overall cardiovascular event-free survival rate was 58.5%. The 6-month angiographic study indicated a 20% restenosis rate. The minimal luminal diameter increased from 0.65 ± 0.44 mm to 3.02 ± 0.46 mm immediately after stenting, decreased to 2.06 ± 0.77 mm at the 6-month follow-up, and increased to 2.27 ± 0.68 mm at the 3- to 5-year follow-up. CONCLUSIONS: This study provides clinical and angiographic results from a large population of patients who underwent BMS implantations after a long-term follow-up period (149 ± 51 months). The progression of coronary atherosclerosis developed over time, and presented with new lesion required stent implantation. The follow-up angiographic findings reconfirmed the late and sustained improvement in luminal diameter between 6 months and 3-5 years.

Dual protection therapy with staged coronary artery bypass surgery and stenting in patients with left main coronary artery stenosis: long-term results from a single center.

OBJECTIVE: We evaluated the efficacy and safety of dual protection therapy with staged coronary artery bypass grafting (CABG) and bare-metal stenting (BMS) in patients with left main coronary artery (LMCA) disease. BACKGROUND: CABG is currently the preferred therapy for complex LMCA disease; however, the long-term patency rates of these grafts are unsatisfactory, and stenting alone for LMCA may be associated with the potentially fatal consequences of stent thrombosis or restenosis. METHODS: Between January 1997 and October 2005, 42 patients underwent staged bypass surgery and BMS, with the latter procedure performed 2 weeks after the initial CABG. Of these patients, 40 received left internal mammary artery (LIMA) grafts, 34 saphenous vein grafts, 6 radial artery grafts, and 3 right IMA (RIMA) grafts. Minimally invasive bypass surgery was performed in 10 patients. RESULTS: There were no operative complications. Forty-two stents were implanted in 42 lesions without complications. During the follow-up period of 135 ± 55 months, 1 patient died of cancer, 2 of cardiac causes, and 5 patients (12%) experienced target lesion revascularization. The target vessel failure rate was 24%. Forty patients (95%) underwent a 6-month angiographic follow-up. Restenosis was noted in 7 patients (18%). Reocclusion was also noted in 5 LIMA grafts, 5 saphenous vein grafts, 1 radial artery graft, and 1 RIMA graft. Only 1 patient experienced both restenosis of LM stenting and total occlusion of the 2 bypass grafts. CONCLUSIONS: Dual protection therapy with staged CABG and stenting is not an appropriate therapeutic strategy because of unacceptable graft patency rate. A higher occlusive rate of the bypass grafts may result from decreased blood flow because of competing blood flow between the bypass graft and the native coronary vessel.

Local sustained delivery of acetylsalicylic acid via hybrid stent with biodegradable nanofibers reduces adhesion of blood cells and promotes reendothelialization of the denuded artery.

Incomplete endothelialization, blood cell adhesion to vascular stents, and inflammation of arteries can result in acute stent thromboses. The systemic administration of acetylsalicylic acid decreases endothelial dysfunction, potentially reducing thrombus, enhancing vasodilatation, and inhibiting the progression of atherosclerosis; but, this is weakened by upper gastrointestinal bleeding. This study proposes a hybrid stent with biodegradable nanofibers, for the local, sustained delivery of acetylsalicylic acid to injured artery walls. Biodegradable nanofibers are prepared by first dissolving poly(D,L)-lactide-co-glycolide and acetylsalicylic acid in 1,1,1,3,3,3-hexafluoro-2-propanol. The solution is then electrospun into nanofibrous tubes, which are then mounted onto commercially available bare-metal stents. In vitro release rates of pharmaceuticals from nanofibers are characterized using an elution method, and a highperformance liquid chromatography assay. The experimental results suggest that biodegradable nanofibers release high concentrations of acetylsalicylic acid for three weeks. The in vivo efficacy of local delivery of acetylsalicylic acid in reducing platelet and monocyte adhesion, and the minimum tissue inflammatory reaction caused by the hybrid stents in treating denuded rabbit arteries, are documented. The proposed hybrid stent, with biodegradable acetylsalicylic acid-loaded nanofibers, substantially contributed to local, sustained delivery of drugs to promote re-endothelialization and reduce thrombogenicity in the injured artery. The stents may have potential applications in the local delivery of cardiovascular drugs. Furthermore, the use of hybrid stents with acetylsalicylic acid-loaded nanofibers that have high drug loadings may provide insight into the treatment of patients with high risk of acute stent thromboses.