Impact of area strain by 3D speckle tracking on clinical outcome in patients after acute myocardial infarction.

BACKGROUND: Three-dimensional (3D) speckle tracking echocardiography (STE) has been developed to overcome the limitations of two-dimensional (2D) STE and has been applied in the several clinical settings. However, no data exist about the prognostic value of 3DSTE-based strain on clinical outcome after myocardial infarction (MI). This study was designed to investigate the prognostic value of area strain (AS) by 3D speckle tracking in predicting clinical outcome after acute MI. METHODS: We assessed 96 patients (62±14 years, 72% male) with acute MI and who had undergone a coronary angiography. Clinical parameters and conventional echocardiographic measurements including the left atrial (LA) size and tissue Doppler measurements were evaluated. The global left ventricular (LV) AS was measured using 3D speckle tracking software. The relationship between the AS and clinical outcome of death or hospitalization for heart failure (HF) was assessed. RESULTS: During a median follow-up of 33±10 months, primary endpoint of death or HF occurred in 12 patients (12.5%). AS was predictive of death or HF after adjustment for age, gender, peak CK-MB, LA volume, LV end-systolic volume, LV mass, the ratio of early mitral inflow velocity to early mitral annular velocity, and LV ejection fraction in a multivariate Cox model (HR 1.23, 95% CI 1.02-1.47, P=.03). In addition, AS added incremental value in predicting death or heart failure on a model based on clinical and standard echocardiographic measures (P=.008). CONCLUSION: AS is independently associated with increased risk of death or HF after acute MI, suggesting that it can be a useful prognostic parameter in the patients following MI.

The relationship between J wave on the surface electrocardiography and ventricular fibrillation during acute myocardial infarction.

We investigated whether the presence of J wave on the surface electrocardiography (sECG) could be a potential risk factor for ventricular fibrillation (VF) during acute myocardial infarction (AMI). We performed a retrospective study of 317 patients diagnosed with AMI in a single center from 2009 to 2012. Among the enrolled 296 patients, 22 (13.5%) patients were selected as a VF group. The J wave on the sECG was defined as a J point elevation manifested through QRS notching or slurring at least 1 mm above the baseline in at least two leads. We found that the incidence of J wave on the sECG was significantly higher in the VF group. We also confirmed that several conventional risk factors of VF were significantly related to VF during AMI; time delays from the onset of chest pain, blood concentrations of creatine phosphokinase and incidence of ST-segment elevation. Multiple logistic regression analysis demonstrated that the presence of J wave and the presence of a ST-segment elevation were independent predictors of VF during AMI. This study demonstrated that the presence of J wave on the sECG is significantly related to VF during AMI.

A randomized, open-label, multicenter trial for the safety and efficacy of adult mesenchymal stem cells after acute myocardial infarction.

Recent studies suggest that the intracoronary administration of bone marrow (BM)-derived mesenchymal stem cells (MSCs) may improve left ventricular function in patients with acute myocardial infarction (AMI). However, there is still argumentative for the safety and efficacy of MSCs in the AMI setting. We thus performed a randomized pilot study to investigate the safety and efficacy of MSCs in patients with AMI. Eighty patients with AMI after successful reperfusion therapy were randomly assigned and received an intracoronary administration of autologous BM-derived MSCs into the infarct related artery at 1 month. During follow-up period, 58 patients completed the trial. The primary endpoint was changes in left ventricular ejection fraction (LVEF) by single-photon emission computed tomography (SPECT) at 6 month. We also evaluated treatment-related adverse events. The absolute improvement in the LVEF by SPECT at 6 month was greater in the BM-derived MSCs group than in the control group (5.9% ± 8.5% vs 1.6% ± 7.0%; P=0.037). There was no treatment-related toxicity during intracoronary administration of MSCs. No significant adverse cardiovascular events occurred during follow-up. In conclusion, the intracoronary infusion of human BM-derived MSCs at 1 month is tolerable and safe with modest improvement in LVEF at 6-month follow-up by SPECT. (ClinicalTrials.gov registration number: NCT01392105).

Study design and rationale of "a multicenter, open-labeled, randomized controlled trial comparing three 2nd-generation drug-eluting stents in real-world practice" (CHOICE trial).

BACKGROUND: The second-generation drug-eluting stents (DES) have shown superiority in many studies relating to safety and efficacy when compared with the first-generation DES. However, it is unclear whether there are differences in efficacy and safety among the second-generation DES after long-term follow-up. METHODS: This multicenter, prospective, randomized, open-labeled trial will directly compare the efficacy and safety among the patients treated with either everolimus-eluting stent (EES), zotarolimus-eluting stent with biolinx polymer (ZES-R), or biolimus-eluting stent (BES) with minimal exclusion criteria. The primary end point is a patient-oriented composite consisted of cardiac death, myocardial infarction not clearly attributable to a nontarget vessel and clinically indicated target lesion revascularization at 24-month clinical follow-up post-index procedure. With the hypothesis that "BES is non-inferior to EES" or "BES is non-inferior to ZES-R" in primary end point, approximately 2,600 patients will be assigned to one of the types of stents using a web-based randomization system. CONCLUSIONS: The CHOICE trial will directly compare the efficacy and safety of EES, ZES-R, and BES in everyday clinical practice for long-term follow-up.

Randomized trial comparing the efficacy between different types of paclitaxel-eluting stents: the comparison of efficacy between COroflex PLEASe ANd Taxus stent (ECO-PLEASANT) randomized controlled trial.

AIMS: Paclitaxel-eluting stents (PESs) have been shown to inhibit neointimal hyperplasia after percutaneous coronary intervention. Coroflex Please (B Braun, Melsungen, Germany) is a newly developed PES. We compared the clinical and angiographic efficacy of Coroflex Please with Taxus Liberte (Boston Scientific, Natick, MA) in a real-world practice. METHODS AND RESULTS: We performed a prospective, open-label, randomized, controlled study that enrolled 945 patients undergoing percutaneous coronary interventions in 18 centers in Korea. The primary end point was clinically driven target vessel revascularization at 9 months. The baseline characteristics were mostly similar and comparable between 2 groups. At 9 months, the incidence of clinically driven target vessel revascularization was 14.6% for Coroflex and 6.4% for Taxus, which was significantly different (hazard ratio 2.43, 95% CI 1.50-3.94, noninferiority P value = 1.000). This is well corroborated by the difference of in-stent late loss between 2 stents (0.71 ± 0.64 mm vs 0.52 ± 0.50 mm, P < .001) by 9-month follow-up angiography (n = 415 vs 215). Among secondary clinical end points, stent thrombosis (definite and probable) for 1 year was 2.2% in Coroflex and 1.3% in Taxus (P = .317). Also, myocardial infarction for 9 months was higher in Coroflex group than that in Taxus (4.9% vs 1.6%, P = .012), which was partly contributed by the higher incidence of periprocedural myocardial infarction in Coroflex arm (2.2% vs 0.3%, P = .028). CONCLUSIONS: Coroflex Please was inferior to Taxus Liberte with regard to clinical and angiographic efficacy.

The impact of vascular access for in-hospital major bleeding in patients with acute coronary syndrome at moderate- to very high-bleeding risk.

The aim of our study was to determine the impact of vascular access on in-hospital major bleeding (IHMB) in acute coronary syndrome (ACS). We analyzed 995 patients with non-ST elevation myocardial infarction and unstable angina at the Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA guidelines (CRUSADE) moderate- to very high-bleeding risk scores in trans-radial intervention (TRI) retrospective registry from 16 centers in Korea. A total of 402 patients received TRI and 593 patients did trans-femoral intervention (TFI). The primary end-point was IHMB as defined in the CRUSADE. There were no significant differences in in-hospital and 1-yr mortality rates between two groups. However, TRI had lower incidences of IHMB and blood transfusion than TFI (6.0% vs 9.4%, P = 0.048; 4.5% vs 9.4%, P = 0.003). The patients suffered from IHMB had higher incidences of in-hospital and 1-yr mortality than those free from IHMB (3.1% vs 15.0%, P < 0.001; 7.2% vs 30.0%, P < 0.001). TRI was an independent negative predictor of IHMB (odds ratio, 0.305; 95% confidence interval, 0.109-0.851; P = 0.003). In conclusions, IHMB is still significantly correlated with in-hospital and 1-yr mortality. Our study suggests that compared to TFI, TRI could reduce IHMB in patients with ACS at moderate- to very high-bleeding risk.

Randomized Comparison of Everolimus- and Zotarolimus-Eluting Coronary Stents With Biolimus-Eluting Stents in All-Comer Patients.

BACKGROUND: There is limited data comparing the Xience everolimus-eluting stent (EES) and the Resolute zotarolimus-eluting stent (ZES) with the BioMatrix biolimus-eluting stent (BES). METHODS: This open-label, randomized, noninferiority trial enrolled all-comer patients to be randomly treated with either BES, EES, or ZES in a 1:1:1 ratio in 15 centers across South Korea. The primary end point was a device-oriented composite outcome consisting of cardiac death, target-vessel myocardial infarction, and clinically indicated target lesion revascularization at 24 months. The BES was compared with the EES and the ZES by intention-to-treat analyses with a noninferiority margin of 3.8%, respectively. RESULTS: Because of slow recruitment and low event rates, this trial was prematurely terminated after enrollment of 1935 (75%) of the intended 2580 patients. Of the 1911 patients randomized to either EES (n=638), BES (n=634), or ZES (n =639), the rate of device-oriented composite outcome was 3.6%, 2.2%, and 3.9%, respectively, at 24 months (BES versus EES: absolute risk difference -1.4% [upper limit of 1-sided 95% CI: -3.2%]; Pfor noninferiority <0.001; BES versus ZES: absolute risk difference -1.7% [upper limit of 1-sided 95% CI: -3.6%]; Pfor noninferiority <0.001). CONCLUSIONS: The BES was noninferior to either the EES or the ZES in all-comer patients for device-oriented composite outcome at the 24-month follow-up. However, caution is advised regarding interpretation of these results due to the premature termination of this study. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01397175.

Does the mitral annulus shrink or enlarge during systole? A real-time 3D echocardiography study.

This study was conducted to explore the geometrical changes of the mitral annulus during systole. The 3D shape of the mitral annulus was reconstructed in 13 normal subjects who had normal structure of the mitral apparatus using real-time 3D echocardiography (RT3DE) and 3D computer software. The two orthogonal (antero-posterior and commissure-commissure) dimensions, the areas (2D projected and 3D surface) and the non-planarity of the mitral annulus were estimated during early, mid and late systole. We demonstrated that the MA had a "saddle shape" appearance and it consistently enlarged mainly in the antero-posterior direction from early to late systole with lessening of its non-planarity, as was determined by 3D reconstruction using RT3DE and 3D computer software.

Effects of early losartan therapy on ventricular late potentials in acute myocardial infarction.

BACKGROUND: Ventricular late potentials (LPs) obtained by the signal-averaged electrocardiogram (SAECG) have prognostic significance as independent predictors of arrhythmic events after an acute myocardial infarction (AMI). Angiotensin receptor blockers reduce the overall mortality and risk of sudden cardiac death in postinfarction patients. The aim of this study was to investigate the effect of early losartan therapy on ventricular LPs, a noninvasive method for the evaluation of arrhythmogenic substrates in AMI patients. METHODS: The study included 97 patients with their first AMI. Forty-eight patients (39 men and 9 women, aged 58.8 +/- 13.19 years), received early losartan therapy. The control group consisted of 49 patients (38 men and 11 women, aged 59.55 +/- 11.0 years), did not received early losartan therapy. The SAECG was performed at admission and day 14. RESULTS: The baseline clinical, angiographic characteristics, and reperfusion methods were similar in both groups. The baseline SAECG findings were also similar in the two groups. There was a significant decrease in the rate of LP, between the first and last SAECG recordings, after reperfusion therapy in the losartan group. All of the parameters of LPs were significantly improved in the losartan group on the last SAECG recordings. CONCLUSION: The results of this study showed that losartan treatment, early after an AMI, reduced the incidence of LP and may thus favorably affect arrhythmia substrates.

Assessment of left ventricular asynchrony using volume-time curves of 16 segments by real-time 3 dimensional echocardiography: comparison with tissue Doppler imaging.

BACKGROUND: Recent technical developments with high-resolution real-time 3 dimensional echocardiography (RT3DE) facilitate the acquisition of high quality images and the analysis of segmental volume-time curves (VTCs). AIMS: To assess left ventricular (LV) asynchrony using the VTCs of 16 segments by RT3DE, and to evaluate accuracy compared to tissue Doppler imaging (TDI). METHODS: Twenty-three heart failure (HF) patients (LVEF: 25+/-6%, age: 60+/-13 years) and 16 normal controls underwent TDI and RT3DE. The standard deviation (SD3) of the end systolic time reaching minimal systolic volume for the 16 segments on VTCs was obtained by RT3DE. The standard deviation (SD2) of the electromechanical coupling time for the 8 segments was measured using TDI. RESULTS: SD3 was markedly higher in HF patients than in controls (7.7+/-2.5 vs 1.5+/-1.0%, P<0.01) and increased as LVEF decreased (r=-0.85, P<0.01). SD2 was also significantly higher in HF patients (27.0+/-8.6 vs 12.6+/-5.0 ms, P<0.01) and had a good negative correlation with LVEF (r=-0.72, P<0.01). SD3 was well correlated to SD2 (r=0.66, P<0.01). CONCLUSIONS: We suggest that analysis of VTCs in 16 segments using RT3DE may be a useful alternative to TDI for the evaluation of LV asynchrony.

The relationship between the left atrial volume and the maximum P-wave and P-wave dispersion in patients with congestive heart failure.

PURPOSE: A maximum P-wave duration (Pmax) of > or = 110 msec and a P-wave dispersion (PWD) > or = 40 msec are accepted indicators of a disturbance in interatrial conduction and an inhomogeneous propagation of the sinus impulse, respectively. The left atrial (LA) volume has been reported to be strongly associated with a systolic and diastolic dysfunction and is considered to be an index of atrial remodeling. We aimed to investigate the relationship between LA volume and Pmax or PWD in patients with congestive heart failure (CHF). PATIENTS AND METHODS: Sixty-one patients with CHF were enrolled in this study. The study population was classified into four groups: two groups were divided according to the Pmax (> or = 110 msec or < 110 ms), and the other two groups were formed based on the PWD (> or = 40 msec or < 40 msec). The left atrial volume index (LAVi) was measured by three-dimensional (3-D) transthoracic echocardiography. The Pmax and PWD were measured from a 12-lead electrocardiogram. RESULTS: There were significant differences in the ejection fraction (EF), diastolic function, and LAVi between patients with a Pmax > or = 110 ms or a PWD > or = 40 ms and those with a Pmax < 110 ms or a PWD < 40 ms. The LAVi was independently associated with a disturbance in interatrial conduction and an inhomogeneous propagation of the sinus impulse. The LAVi can be used to identify patients with a disturbance in interatrial conduction and an inhomogeneous propagation of the sinus impulse with reasonably good accuracy. CONCLUSION: We concluded that a disturbance in interatrial conduction and an inhomogeneous propagation of the sinus impulse in patients with CHF is associated with an increase in the LA volume and a deleterious systolic and diastolic dysfunction.

Beneficial Effects of Bariatric Surgery on Cardiac Structure and Function in Obesity.

BACKGROUND: Bariatric surgery is being considered as a therapeutic option for morbidly obese patients. Data are accumulating showing that this surgical intervention may improve in major cardiovascular morbidity and mortality. We evaluated the effects of bariatric surgery on left ventricular (LV) structure and function including LV mechanics in obese patients. METHODS: Thirty-seven patients (age = 36 ± 10 years; male:female = 11:26) undergoing bariatric surgery were enrolled. Echocardiography was performed before and after at least 1 year of bariatric surgery. Conventional echocardiographic parameters, including tissue Doppler measurements, were measured. LV global longitudinal, circumferential, and radial deformations were assessed utilizing 2D speckle tracking software. RESULTS: Patients decreased body mass index by 11.8 ± 4.7 over 15.6 ± 5.5 months. Bariatric surgery led to significant decreases in left ventricular (LV) size and mass (51.0 ± 3.3 to 49.1 ± 3.4 mm, p < 0.001 for LV end-diastolic dimension; 192.6 ± 33.5 to 146.2 ± 29.1 g, p < 0.001 for LV mass), and increases were noted in the ratio of early-to-late diastolic mitral inflow (E/A), early diastolic tissue Doppler velocity (Em), and LV longitudinal strain (1.42 ± 0.52 to 1.59 ± 0.56, p = 0.04 for E/A ratio; 9.7 ± 2.0 to 11.0 ± 2.4 cm/s, p < 0.001 for Em; 14.1 ± 1.9 to 16.2 ± 1.4 %, p < 0.001 for longitudinal strain). Changes of LV longitudinal strain were related to LV mass reduction (p = 0.04). However, LV ejection fraction, LV circumferential, and radial strains were all comparable at follow-up. CONCLUSION: Significant weight loss by bariatric surgery was associated with improved LV structure and function in obese patients, suggesting potential favorable effects of bariatric surgery to prevent future cardiovascular events.

Prognostic Implications of Newly Developed T-Wave Inversion After Primary Percutaneous Coronary Intervention in Patients With ST-Segment Elevation Myocardial Infarction.

We investigated the prognostic value of newly developed T-wave inversion after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction. New T-wave inversion was defined as new onset of T-wave inversion after the primary PCI, without negative T waves on the presenting electrocardiogram. The primary end point was the occurrence of major adverse cardiac events (MACE), which consisted of cardiovascular mortality, nonfatal myocardial infarction, and rehospitalization for heart failure. A total of 271 patients were analyzed and followed up for 24 months in this study. New T-wave inversion was observed in 194 patients (72%), whereas the remaining 77 patients (28%) did not show T-wave inversion after the index PCI. Post-PCI Thrombolysis In Myocardial Infarction flow grade 2 or 3 was observed more frequently in patients with new T-wave inversion (97% vs 90%; p = 0.011). The cumulative MACE rate was significantly lower in patients with new T-wave inversion than in those without new T-wave inversion (8% vs 30%; odds ratio 0.197, 95% confidential interval 0.096 to 0.403; p <0.001). In multivariate Cox regression analysis, new T-wave inversion was an independent prognostic factor for MACE (hazard ratio 0.297, 95% confidential interval 0.144 to 0.611; p = 0.001). In conclusion, newly developed T-wave inversion after primary PCI was associated with favorable long-term outcome.

Epicardial Artery Stenosis with a High Index of Microcirculatory Resistance Is Frequently Functionally Insignificant as Estimated by Fractional Flow Reserve (FFR).

Objective Differences in microvascular integrity can diversely influence the functional assessment of epicardial coronary artery disease in each patient. We investigated the relevance of the index of microcirculatory resistance (IMR) and fractional flow reserve (FFR) of intermediate coronary lesions. Methods The IMR and FFR were measured in 67 intermediate coronary lesions of the left anterior descending artery of 67 patients, by using a pressure sensor/thermistor-tipped guidewire. Results To assess the differences in FFR in relationship to the IMR value, patients were divided into tertile IMR groups as follows: Low-IMR (n=22, IMR 14±3), Mid-IMR (n=23, IMR 21±2), and High-IMR (n=22, IMR 36±10). An analysis of variance showed that the High-IMR group had significantly higher FFR values (0.87±0.07) than the Low-IMR group (0.81±0.08) (p=0.03). Functionally significant lesions with FFR ≤0.8 accounted for 9% of lesions in the High-IMR group, 36% in the Low-IMR group and 22% in the Mid-IMR group (p=0.02). In the multivariate logistic analysis, the IMR value was an independent determinant of FFR ≤0.8 (p=0.03). Conclusion In patients with a high IMR, intermediate lesions as identified with visual estimation were more frequently functionally insignificant. The IMR can provide additional information in understanding the mismatch between the anatomical and functional severity of intermediate coronary stenosis.

Comprehensive assessment of microcirculation after primary percutaneous intervention in ST-segment elevation myocardial infarction: insight from thermodilution-derived index of microcirculatory resistance and coronary flow reserve.

OBJECTIVES: A pathophysiological mechanism of microvascular dysfunction in ST-segment elevation myocardial infarction (STEMI) is multifactorial; thus, multiple modalities were needed to precisely evaluate a microcirculation. METHODS: We complementarily assessed microcirculation in STEMI by the index of microcirculatory resistance (IMR) and coronary flow reserve (CFR) immediately after a primary percutaneous intervention in 89 STEMI patients. Cardiovascular and cerebrovascular events (MACCE) including cardiovascular death, target vessel failure, heart failure, and stroke were assessed during a mean follow-up period of 3.0 years. RESULTS: The microcirculation of enrolled patients was classified into four groups using cutoff CFR and IMR values (CFR>2 and mean IMR): group-1 (n=23, CFR>2 and IMR ≤ 27); group-2 (n=31, CFR ≤ 2 and IMR ≤ 27); group-3 (n=9, CFR>2 and IMR>27); and group-4 (n=26, CFR<2 and IMR>27). On echocardiography 3 months later, improvement in the wall motion score index was shown in group-1 (P<0.01), group-2 (P<0.01), and group-3 (P=0.04), whereas group-4 did not show improvement in wall motion score index (P=0.06). During clinical follow-up, there were no MACCE in group-1 and the patients in group-2 and group-3 showed significantly lower MACCE compared with group-4 (group-1=0%, group-2, and group-3=10%, group-4=23.1%, P=0.04). CONCLUSION: Complimentary assessment of microcirculation by the IMR and CFR may be useful to evaluate myocardial viability and the long-term prognosis of STEMI patients.

Relation Between Neutrophil-to-Lymphocyte Ratio and Index of Microcirculatory Resistance in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention.

The neutrophil-to-lymphocyte ratio (NLR) has been proved as a reliable inflammatory marker for the atherosclerotic process and as a predictor for clinical outcomes in patients with various cardiovascular diseases. A recent study reported that elevated NLR is associated with impaired myocardial perfusion in patients with ST-segment elevation myocardial infarction (STEMI). We investigated whether NLR is associated with coronary microcirculation as assessed by the index of microcirculatory resistance (IMR) in patients with STEMI who had undergone primary percutaneous coronary intervention (PCI). A total of 123 patients with STEMI who underwent successful primary PCI were enrolled in this study. NLR was obtained on admission, and patients were divided into 3 groups by NLR tertile. IMR was measured using an intracoronary thermodilution-derived method immediately after index PCI. Symptom onset-to-balloon time was significantly longer (p = 0.005), and IMR was significantly higher in the high NLR group than that in the low and intermediate groups (21.94 ± 12.87 vs 23.22 ± 12.73 vs 32.95 ± 20.60, p = 0.003). Furthermore, in multiple linear regression analysis, NLR showed an independent positive correlation with IMR (r = 0.205, p = 0.009). In conclusion, NLR has shown positive correlation with IMR, whereas negative association with infarct-related artery patency in patients with STEMI who underwent primary PCI. Therefore, NLR at admission could reflect myocardial damage and the status of coronary microcirculation in patients with STEMI (ClinicalTrials.gov number, NCT02828137).

Randomised trial to compare a protective effect of Clopidogrel Versus TIcagrelor on coronary Microvascular injury in ST-segment Elevation myocardial infarction (CV-TIME trial).

AIMS: Ticagrelor has shown greater, more rapid and more consistent platelet inhibition than clopidogrel. However, the superiority of ticagrelor for preventing ischaemic damage in STEMI patients has not been proven. The aim of this trial was to assess whether ticagrelor is superior to clopidogrel in preventing microvascular injury in ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: Patients with STEMI underwent prospective random assignment to receive a loading dose (LD) of clopidogrel 600 mg or ticagrelor 180 mg (1:1 ratio) before primary percutaneous coronary intervention (PCI). As the primary endpoint, the index of microcirculatory resistance (IMR) was measured immediately after primary PCI. The secondary endpoint was the infarct size estimated from the wall motion score index (WMSI). A total of 76 patients were enrolled (clopidogrel group=38, ticagrelor group=38). The IMR in the ticagrelor group was significantly lower than that in the clopidogrel group (22.2±18.0 vs. 34.4±18.8 U, p=0.005). Cardiac enzymes were less elevated in the ticagrelor group than in the clopidogrel group (CK peak; 2,651±1,710 vs. 3,139±2,698 ng/ml, p=0.06). Infarct size, estimated by WMSI, was not different between the ticagrelor and clopidogrel groups at baseline (1.55±0.30 vs. 1.61±0.29, p=0.41) or after three months (1.42±0.33 vs. 1.47±0.33, p=0.57). CONCLUSIONS: In patients with STEMI treated by primary PCI, a 180 mg LD of ticagrelor might be more effective in reducing microvascular injury than a 600 mg LD of clopidogrel, as demonstrated by IMR immediately after primary PCI.

Comparison of Transradial and Transfemoral Approaches for Percutaneous Coronary Intervention in Patients With Acute Coronary Syndrome and Anemia.

Anemia is an independent predictor of bleeding complications and poor clinical outcomes after percutaneous coronary intervention. Percutaneous coronary transradial intervention (TRI) is better than percutaneous coronary transfemoral intervention (TFI) in terms of reducing bleeding complications that can affect the prognosis. This study aims to investigate the clinical outcomes between TRI and TFI for patients with anemia. We analyzed periprocedure complications, in-hospital mortality, and major adverse cardiac events for one year in the Korean TRI registry from January 2013 to April 2014. Patients with chronic kidney disease for whom TFI is preferred were excluded. Anemia was defined as hemoglobin <13 g/dl for men and <12 g/dl for women. A total of 1,279 patients were finally enrolled. Of these, 348 patients had anemia. Among them, 253 patients (72.7%) underwent TRI and 95 patients (27.3%) underwent TFI. There were no significant differences of baseline demographic characteristics between the TRI and TFI groups, except for the incidence of dyslipidemia (TRI 23.7% vs TFI 12.6%, p = 0.023). Multivariate logistic regression analysis revealed lower incidence of composite severe bleeding complications (hazard ratio 0.34, 95% CI 0.12 to 0.99, p = 0.049) and lower incidence of in-hospital mortality than TFI group (hazard ratio 0.74, 95% CI 0.62 to 0.88, p = 0.042). In conclusion, this study suggests that the TRI for patients with anemia may be translated into better prognosis in terms of lower rates of bleeding complications and in-hospital mortality.

Clinical and Angiographic Predictors of Microvascular Dysfunction in ST-Segment Elevation Myocardial Infarction.

PURPOSE: We aimed to discover clinical and angiographic predictors of microvascular dysfunction using the index of microcirculatory resistance (IMR) in patients with ST-segment elevation myocardial infarction (STEMI). MATERIALS AND METHODS: We enrolled 113 patients with STEMI (age, 56±11 years; 95 men) who underwent primary percutaneous coronary intervention (PCI). The IMR was measured with a pressure sensor/thermistor-tipped guidewire after primary PCI. The patients were divided into three groups based on IMR values: Low IMR [<18 U (12.9±2.6 U), n=38], Mid IMR [18-31 U (23.9±4.0 U), n=38], and High IMR [>31 U (48.1±17.1 U), n=37]. RESULTS: The age of the Low IMR group was significantly lower than that of the Mid and High IMR groups. The door-to-balloon time was <90 minutes in all patients, and it was not significantly different between groups. Meanwhile, the symptom-onset-to-balloon time was significantly longer in the High IMR group, compared to the Mid and Low IMR groups (p<0.001). In the high IMR group, the culprit lesion was found in a proximal location significantly more often than in a non-proximal location (p=0.008). In multivariate regression analysis, age and symptom-onset-to-balloon time were independent determinants of a high IMR (p=0.013 and p=0.003, respectively). CONCLUSION: Our data suggest that age and symptom-onset-to-balloon time might be the major predictors of microvascular dysfunction in STEMI patients with a door-to-balloon time of <90 minutes.

Clinical and Echocardiographic Factors Affecting Tricuspid Regurgitation Severity in the Patients with Lone Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) can be a risk factor for development of significant tricuspid regurgitation (TR). We investigated which clinical and echocardiographic parameters were related to severity of functional TR in patients with lone AF. METHODS: A total of 89 patients with lone AF were enrolled (75 ± 11 years; 48% male): 13 patients with severe TR, 36 patients with moderate TR, and 40 consecutive patients with less than mild TR. Clinical parameters and echocardiographic measurements including right ventricular (RV) remodeling and function were evaluated. RESULTS: Patients with more severe TR were older and had more frequently persistent AF (each p < 0.001). TR severity was related to right atrial area and tricuspid annular systolic diameter (all p < 0.001). The patients with moderate or severe TR had larger left atrial (LA) volume and increased systolic pulmonary artery pressure (SPAP) than the patients with mild TR (p = 0.04 for LA volume; p < 0.001 for SPAP). RV remodeling represented by enlarged RV area and increased tenting height was more prominent in severe TR than mild or moderate TR (all p < 0.001). Multivariate analysis showed type of AF, LA volume, tricuspid annular diameter and tenting height remained as a significant determinants of severe TR. In addition, tenting height was independently associated with the presence of severe TR (p = 0.04). CONCLUSION: In patients with lone AF, TR was related to type of AF, LA volume, tricuspid annular diameter and RV remodeling. Especially, tricuspid valvular tethering seemed to be independently associated with development of severe functional TR.