Optical coherence tomography characterization of degradation kinetics between second- and third-generation resorbable magnesium scaffold.

AIMS: This preclinical study aimed to establish optical coherence tomography (OCT)-derived parameters that could be used in the clinical setting for assessing strut degradation in the third-generation drug-eluting resorbable magnesium scaffold (DREAMS-3G), and characterize the comparative degradation profile against its precursor device (MagmarisTM scaffold). METHODS AND RESULTS: Twelve DREAMS-3G and 10 MagmarisTM scaffolds were implanted in juvenile pigs, and OCT images obtained at baseline and follow-up (6 or 12 months). Strut degradation was assessed by planimetric analysis and compared with OCT-derived indices to validate their diagnostic accuracy. A total of 3327 struts of DREAMS-3G and 2995 struts of the MagmarisTM scaffold were delineated by OCT. DREAMS-3G exhibited a significantly higher number of visible struts per analyzed frame at 6 months than the MagmarisTM scaffold, in the absence of significant differences at 12 months. Attenuation index (AtI) analysis indicated DREAMS-3G degradation was less advanced at 6 months but more advanced at 12 months compared to the MagmarisTM scaffold. These OCT-derived indices significantly correlated with the results of the planimetric analysis. CONCLUSION: The current preclinical study validated OCT indices that may serve as clinical surrogate markers for scaffold degradation. AtI analysis indicated that DREAMS-3G showed less degradation at 6 months but more advanced degradation at 12 months compared to the MagmarisTM scaffold, which corroborates the findings from planimetric analysis.

Determinants of serious in-hospital complications in patients with Killip class 1/2 ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention.

Killip classification has been used to stratify the risk of patients with acute myocardial infarction (AMI). There were many reports that Killip class 3 or 4 is closely associated with poor clinical outcomes. In other words, Killip class 1 or 2 is associated with favorable clinical outcomes in patients with AMI, especially when patients received primary percutaneous coronary intervention (PCI). However, some patients with Killip class 1/2 suffer from serious in-hospital complications. This study aimed to identify factors associated with serious in-hospital complications of ST-segment elevation myocardial infarction (STEMI) in patients with Killip class 1/2. The primary endpoint was serious in-hospital complications defined as the composite of in-hospital death and mechanical complications. We included 809 patients with STEMI, and divided them into the non-complication group (n = 791) and the complication group (n = 18). In-hospital death was observed in 14 patients (1.7%), and mechanical complications were observed in 4 patients (0.5%). Final TIMI flow ≤ 2 was more frequently observed in the complication group (33.3%) than in the non-complication group (5.4%) (p < 0.001). Multivariate logistic regression analysis revealed that serious in-hospital complication was associated with final TIMI flow grade ≤ 2 (Odds ratio 6.040, 95% confidence interval 2.042-17.870, p = 0.001). In conclusion, serious in-hospital complication of STEMI was associated with insufficient final TIMI flow grade in patients with Killip class 1/2. If final TIMI flow grade is suboptimal after primary PCI, we may recognize the potential risk of serious complications even when patients presented as Killip class 1/2.

Creatinine kinase-myocardial band (CK-MB) to creatinine kinase (CK) ratio for ST-segment elevation myocardial infarction in the era of the universal definition.

Although serum troponin level is the gold standard under the universal definition of acute myocardial infarction (AMI), serum creatinine kinase (CK) and creatine kinase-myocardial band (CK-MB) is still measured in clinical practice as the compliment of troponin level. The purpose of this retrospective study is to illustrate the dramatic change of CK-MB/CK ratio by comparing CK-MB/CK ratio in patients with ST-segment elevation myocardial infarction (STEMI) among ≤ 24 h before reaching peak CK, peak CK, ≤ 24 h after reaching peak CK, and 24-48 h after reaching peak CK. We included 502 patients with STEMI. We calculated each average CK-MB/CK ratio at ≤ 24 h before reaching peak CK, peak CK, ≤ 24 h after reaching peak CK, and 24-48 h after reaching peak CK. The average values were compared using Friedman test. The average CK-MB/CK ratio at ≤ 24 h before reaching peak CK, peak CK, ≤ 24 h after reaching peak CK, and 24-48 h after reaching peak CK was 0.096 (9.6% of CK), 0.098 (9.8% of peak CK), 0.076 (7.6% of CK), and 0.028 (2.8% of CK), respectively. The Friedman test suggested that the CK-MB/CK ratio significantly declined after reaching peak CK (p < 0.001). In conclusion, the CK-MB/CK ratio was around 0.1 (10% of CK) until CK-MB and CK reached the peak, but dropped sharply after reaching peak CK. The CK-MB/CK ratio less than 0.1 (10% of CK) cannot be used to rule out the possibility of AMI, when the onset of symptom is unclear or late presentation.

Development of a simple prediction model for mechanical complication in ST-segment elevation myocardial infarction patients after primary percutaneous coronary intervention.

Mechanical complication (MC) is a rare but serious complication in patients with ST-segment elevation myocardial infarction (STEMI). Although several risk factors for MC have been reported, a prediction model for MC has not been established. This study aimed to develop a simple prediction model for MC after STEMI. We included 1717 patients with STEMI who underwent primary percutaneous coronary intervention (PCI). Of 1717 patients, 45 MCs occurred after primary PCI. Prespecified predictors were determined to develop a tentative prediction model for MC using multivariable regression analysis. Then, a simple prediction model for MC was generated. Age ≥ 70, Killip class ≥ 2, white blood cell ≥ 10,000/µl, and onset-to-visit time ≥ 8 h were included in a simple prediction model as "point 1" risk score, whereas initial thrombolysis in myocardial infarction (TIMI) flow grade ≤ 1 and final TIMI flow grade ≤ 2 were included as "point 2" risk score. The simple prediction model for MC showed good discrimination with the optimism-corrected area under the receiver-operating characteristic curve of 0.850 (95% CI: 0.798-0.902). The predicted probability for MC was 0-2% in patients with 0-4 points of risk score, whereas that was 6-50% in patients with 5-8 points. In conclusion, we developed a simple prediction model for MC. We may be able to predict the probability for MC by this simple prediction model.

Near-infrared spectroscopy-intravascular ultrasound to improve assessment of coronary artery disease severity in patients referred for transcatheter aortic valve implantation (The IMPACTavi registry): Design and rationale.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) was established as a standard treatment for high-operative risk patients with severe aortic stenosis (AS). Although coronary artery disease (CAD) often coexists with AS, clinical and angiographic evaluations of stenosis severity are unreliable in this specific setting. To provide precise risk stratification of coronary lesions, combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) was developed to integrate morphological and molecular information on plaque composition. However, there is a lack of evidence on the association between NIRS-IVUS derived findings such as maximum 4mm lipid core burden index (maxLCBI4mm) and clinical outcomes in AS patients undergoing TAVI. This registry aims to assess feasibility and safety of NIRS-IVUS imaging in the setting of routine pre-TAVI coronary angiography to improve assessment of CAD severity. METHODS: The registry is designed as a non-randomized, prospective, observational, multicenter cohort registry. Patients referred for TAVI with angiographic evidence of CAD receive NIRS-IVUS imaging and are followed up to 24 months. Enrolled patients are classified as NIRS-IVUS positive and NIRS-IVUS negative, respectively, based on their maxLCBI4mm to compare their clinical outcomes. The primary endpoint of the registry is major adverse cardiovascular events over a 24-month follow-up period. CONCLUSIONS: Identification of patients likely or unlikely to benefit from revascularization prior to TAVI represents an important unmet clinical need. This registry is designed to investigate whether NIRS-IVUS-derived atherosclerotic plaque characteristics can identify patients and lesions at risk for future adverse cardiovascular events after TAVI, in order to refine interventional decision-making in this challenging patient population.

Iliofemoral artery predilation prior to transfemoral transcatheter aortic valve implantation in patients with aortic valve stenosis and advanced peripheral artery disease.

OBJECTIVES: To investigate the feasibility and safety of percutaneous transluminal angioplasty (PTA) of the iliofemoral arteries (IFA) before transfemoral transcatheter aortic valve implantation (Tf-TAVI) in patients with advanced peripheral artery disease (PAD). BACKGROUND: Although Tf-TAVI represents the access of choice, alternative vascular access routes are preferred for patients displaying advanced PAD. PTA of the IFA represents a less invasive option, broadening the spectrum of patients eligible for Tf-TAVI. METHODS: All patients requiring PTA of the IFA before Tf-TAVI, between 2012 and 2021, were included. Primary efficacy endpoint was the rate of successful transcatheter heart valve (THV) delivery and implantation. Primary safety endpoint was the rate of PTA and access-site-related vascular complications, procedural- and in-hospital complications. RESULTS: Among 2726 Tf-TAVI procedures, 59 patients required IFA predilation. Successful THV delivery and implantation was achieved in 57 (96.6%) patients, respectively. Sheath placement was achieved in 59 (100%) patients with only one minor dissection and no major vascular complications following iliofemoral PTA. Regarding access site complications, two (3.4%) vessel perforations and one (1.7%) vessel rupture were observed, with eight (13.5%) patients requiring unplanned endovascular interventions. There was one intraprocedural death due to THV-induced vessel laceration, while in-hospital all-cause mortality was 8.5% in the present high-risk patient cohort. CONCLUSIONS: Predilation of IFA is safe and effective in patients with advanced PAD. Careful preprocedural planning is paramount in improving procedural safety and efficacy. This strategy has the potential to broaden the spectrum of patients eligible for Tf-TAVI.

Comparison of in-hospital outcomes of acute myocardial infarction between patients with cardiogenic shock and with cardiac arrest.

In-hospital mortality of acute myocardial infarction (AMI) complicated with cardiogenic shock (CS) remains high. Also, in-hospital mortality of AMI complicated with cardiac arrest (CA) has been reported to be highest among any AMI. However, there were few reports that compared in-hospital mortality directly between AMI complicated with CS and complicated with CA. The purpose of this study was to compare in-hospital outcomes between AMI complicated with CS and complicated with CA. We retrospectively included 195 AMI patients complicated by CS or CA, and divided those into the CA group (n = 109) and the CS group (n = 86). We also subdivided the CA group into CA with persistent CS (n = 83) and CA without persistent CS (n = 26). One-third of the study population died during the index admission. In-hospital death was more frequently observed in the CA group (45.0%) than in the CS group (20.9%) (p < 0.001). In-hospital mortality was highest in the CA with persistent CS group (68.7%), followed by the CS group (20.9%), and least in the CA without persistent CS group (11.5%) (p < 0.001). Favorable neurological function was more frequently observed in the CA without persistent CS group (76.9%) and the CS group (74.4%) than in the CA with persistent CS group (27.7%) (p < 0.001). In conclusion, in-hospital mortality was higher in AMI patients with CA than in those with CS. However, when we divided AMI patients with CA into those with and without persistent CS, in-hospital mortality was lowest in CA without persistent CS, followed by CS, and highest in CA with persistent CS.

Association of peak C-reactive protein with long-term clinical outcomes in patients with ST-segment elevation myocardial infarction.

Peak C-reactive protein (CRP) levels following ST-segment elevation myocardial infarction (STEMI) are associated with left ventricular thrombus formation or cardiac rupture. However, the impact of peak CRP on long-term outcomes in patients with STEMI is not completely understood. The purpose of this retrospective study was to compare the long-term all-cause death after STEMI between patients with and without high peak CRP levels. We included 594 patients with STEMI, and divided them into the high CRP group (n = 119) and the low-moderate CRP group (n = 475) according to the quintile of peak CRP levels. The primary endpoint was all-cause death after the discharge of the index admission. The mean peak CRP level was 19.66 ± 5.14 mg/dL in the high CRP group, whereas that was 6.43 ± 3.86 mg/dL in the low-moderate CRP group (p < 0.001). During the median follow-up duration of 1045 days (Q1 284 days, Q3 1603 days), a total of 45 all-cause deaths were observed. The Kaplan-Meier curves showed that all-cause death was more frequently observed in the high CRP group than in the low-moderate CRP group (p = 0.002). The multivariate Cox hazard analysis revealed that high CRP was significantly associated with all-cause death (hazard ratio 2.325, 95% confidence interval 1.246-4.341, p = 0.008) after controlling for confounding factors. In conclusion, high peak CRP was significantly associated with all-cause death in patients with STEMI. Our results suggest that peak CRP may be useful to stratify patients with STEMI for the risk of future death.

Factors associated with intensive care unit delirium in patients with acute myocardial infarction.

Some patients admitted to intensive care units (ICU) would develop delirium, which is associated with poor prognosis. The purpose of this retrospective study was to identify factors associated with ICU delirium in patients with acute myocardial infarction (AMI). We included 753 AMI and divided those into the ICU-delirium group (n = 110) and the non-ICU-delirium group (n = 643) according to the presence of ICU delirium. The ICU delirium was evaluated by confusion assessment method for the intensive care unit. Patient characteristics and clinical outcomes were compared between the 2 groups, and factors associated with ICU delirium were sought by multivariate analysis. The prevalence of female sex was significantly higher in the ICU-delirium group (43.6%) than in the non-ICU-delirium group (20.2%) (p < 0.001). The incidence of in-hospital death was significantly higher in the ICU-delirium group (17.3%) than in the non-ICU-delirium group (0.5%) (p < 0.001). The multivariate logistic regression analysis revealed that age [every 10 years increase: odds ratio (OR) 1.439, 95% confidence interval (CI) 1.127-1.837, p = 0.004], female sex (OR 2.237, 95%CI 1.300-3.849, p = 0.004), triple vessel disease (OR 2.317, 95%CI 1.365-3.932, p = 0.002), body mass index < 18.5 kg/m2 (OR 2.910, 95%CI 1.410-6.008, p = 0.004), use of mechanical support (OR 2.812, 95%CI 1.500-5.270, p = 0.001), respiratory failure (OR 5.342, 95%CI 3.080-9.265, p < 0.001), and use of continuous renal replacement therapy (OR 5.901, 95%CI 2.520-13.819, p < 0.001) were significantly associated with ICU delirium. In conclusion, ICU delirium was associated with in-hospital death. Older age, female sex, triple vessel disease, leanness, use of mechanical support, respiratory failure, and continuous renal replacement therapy were significantly associated with the occurrence of ICU delirium.

Impact of intravascular ultrasound-incomplete stent apposition on stent failure.

OBJECTIVES: This study aimed to investigate the relationship between immediate incomplete stent apposition (ISA) detected by intravascular ultrasound (IVUS) and midterm stent failure. BACKGROUND: Stent failure is one of serious clinical events related to percutaneous coronary intervention (PCI). The previous studies using optical coherence tomography showed that ISA could be associated with stent thrombosis. However, the association between immediate ISA detected by IVUS and stent failure has not been fully investigated. METHODS: We included 396 lesions that underwent elective PCI, and divided those into the appropriate stent apposition (ASA) group (n = 290) and the ISA group (n = 106). The primary endpoint was stent failure, which was defined as a composite of ischemia-driven target lesion revascularization and stent thrombosis. We compared clinical and lesion characteristics between the two groups, and performed a multivariate COX hazard analysis to investigate the association between immediate ISA and stent failure. RESULTS: The median follow-up duration was 1296 days. The Kaplan-Meier curves revealed the higher incidence of stent failure in the ISA group than in the ASA group (p < 0.001). The multivariate stepwise COX hazard analysis showed that immediate ISA (hazard ratio 4.97, 95% confidence interval 1.31-18.82, p = 0.018) was significantly associated with stent failure. When we set the cut-off value of the immediate ISA distance as 0.25 mm, the distance ≥ 0.25 mm had 68.8% sensitivity and 85.0% specificity to predict stent failure. CONCLUSIONS: Immediate ISA detected by IVUS was associated with midterm stent failure. We should pay attention to reduce immediate ISA for improving the midterm outcomes.

Comparison of Long-Term Clinical Outcomes in Patients Stratified by a Novel Acute Myocardial Infarction Risk Stratification (nARS) System.

BACKGROUND: As severity of acute myocardial infarction (AMI) varies widely, several risk stratifications for AMI have been reported. We have introduced a novel AMI risk stratification system linked to a rehabilitation program (novel AMI risk stratification; nARS), which stratified AMI patients into low (L)-, intermediate (I)-, and high (H)-risk groups. The purpose of this retrospective study was to compare the long-term clinical outcomes in patients with AMI among L-, I-, H-risk groups.Methods and Results: This study included 773 AMI patients, and assigned them into the L-risk group (n=332), the I-risk group (n=164), and the H-risk group (n=277). The primary endpoint was major cardiovascular events (MACE), defined as the composite of all-cause death, readmission for heart failure, non-fatal myocardial infarction, and target vessel revascularization after the discharge of index admission. The median follow-up duration was 686 days. MACE was most frequently observed in the H-risk group (39.4%), followed by the I-risk group (23.2%), and least in the L-risk group (19.9%) (P<0.001). The multivariate Cox hazard analysis revealed that the H-risk was significantly associated with MACE (HR 2.166, 95% CI 1.543-3.041, P<0.001) after controlling for multiple confounding factors. CONCLUSIONS: H-risk according to nARS was significantly associated with long-term adverse events after hospital discharge for patients with AMI. These results support the validity of nARS as a risk marker for long-term outcomes.

Association of collateral flow with clinical outcomes in patients with acute myocardial infarction.

Coronary collateral flow is an important prognostic marker in percutaneous coronary intervention (PCI) for chronic total occlusion. However, the role of collateral flow to the culprit lesion of acute myocardial infarction (AMI) has not been fully established yet. The purpose of this retrospective study was to examine the association between collateral flow and long-term clinical outcomes in patients with AMI. We included 937 patients with AMI, and divided those into the no-collateral group (n = 704) and the collateral group (n = 233) according to the presence or absence of collateral flow to the culprit lesion of AMI. The primary endpoint was the incidence of major adverse cardiac events (MACE), which was defined as a composite of all-cause death, non-fatal MI, re-admission for heart failure, and ischemia driven target vessel revascularization. The median follow-up duration was 473 days (Q1: 184 days- Q3: 1027 days), and a total of 263 MACE was observed during the study period. The incidence of MACE was significantly greater in the no-collateral group than in the collateral group (29.8% vs. 22.3%, p = 0.027). In the multivariate COX hazard model, the presence of collateral flow was inversely associated with MACE (HR 0.636, 95% CI 0.461-0.878, p = 0.006) after controlling multiple confounding factors. In conclusion, the presence of collateral flow to the culprit lesion of AMI was inversely associated with long-term adverse outcomes. Careful observation of collateral flow may be important in emergent coronary angiography to stratify a high-risk group among various patients with AMI.

Association of Increased Pulse Wave Velocity With Long-Term Clinical Outcomes in Patients With Preserved Ankle-Brachial Index After Acute Myocardial Infarction.

BACKGROUND: Low ankle-brachial index (ABI) is an established risk factor for long-term cardiovascular outcomes in patients with acute myocardial infarction (AMI), and brachial-ankle pulse wave velocity (ba-PWV) may also be a risk factor. However, there is a significant overlap between low ABI and high ba-PWV. The purpose of this retrospective study was to examine whether increased ba-PWV was associated with long-term clinical outcomes in AMI patients with normal ABI. METHODS: We included 932 AMI patients with normal ABI and divided them into the high PWV group (≥1,400 cm/s; n=646) and the low PWV group (<1400 cm/s; n=286) according to the ba-PWV values measured during the AMI hospitalisation. The primary endpoint was the major adverse cardiovascular events (MACE) defined as the composite of all-cause death, nonfatal myocardial infarction, and hospitalisation for heart failure. RESULTS: During the median follow-up duration of 541 days (Q1: 215 days-Q3: 1,022 days), a total of 154 MACE were observed. The Kaplan-Meier curves showed that MACE was more frequently observed in the high PWV group than in the low PWV group (p<0.001). The multivariate Cox hazard analysis revealed that high ba-PWV was significantly associated with MACE (hazard ratio [HR] 1.587; 95% CI 1.002-2.513; p=0.049) after controlling multiple confounding factors. CONCLUSIONS: High ba-PWV was significantly associated with long-term adverse events in AMI patients with normal ABI. Our results suggest the usefulness of PWV as a prognostic marker in AMI with normal ABI.

Comparison of the Incidence of Periprocedural Myocardial Infarction in Bifurcation Lesions Between Medina (1,1,1) and (0,1,1) in Elective Percutaneous Coronary Intervention.

Periprocedural myocardial infarction (PMI) following percutaneous coronary intervention (PCI) is more frequently observed in true bifurcation lesions such as Medina (1,1,1) and (0,1,1). The aim of this study is to compare the incidence of PMI in elective PCI between Medina (1,1,1) and (0,1,1) bifurcation lesions. This was a retrospective, single-center study. We included 162 true bifurcation lesions, which were divided into the (1,1,1) group (n = 85) and the (0,1,1) group (n = 77). We compared the incidence of PMI between the two groups and performed multivariate logistic regression analysis using PMI as a dependent variable. The incidence of PMI was similar in the (1,1,1) group and the (0,1,1) group (12.9% versus 15.6%, P = 0.658). The final TIMI flow grade of the side branches and that of the main branches were also similar in the two groups. In multivariate logistic regression analysis, Medina classification (1,1,1) was not associated with PMI (odds ratio (OR), 0.996; 95% confidence interval (CI), 0.379-2.621; P = 0.994), but the angle of the side branch < 45° (OR, 3.569; 95% CI, 1.320-9.654; P = 0.012), lesion length in a main vessel (per 10-mm increase) (OR, 1.508; 95% CI, 1.104-2.060; P = 0.010), and absence of side branch protection (OR, 3.034; 95% CI, 1.095-8.409; P = 0.033) were significantly associated with PMI. In conclusion, the Medina (1,1,1) bifurcation lesions did not increase the incidence of PMI as compared to Medina (0,1,1). However, the narrow side branch angle, diffuse long lesion, and absence of side branch protection were significantly associated with PMI. We should pay attention to these high-risk features in the treatment of true bifurcation lesions.

Comparison of clinical outcomes and left ventricular remodeling after ST-elevation myocardial infarction between patients with and without diabetes mellitus.

Left ventricular remodeling (LVR) after ST-elevation myocardial infarction (STEMI) is generally thought to be an adaptive but compromising phenomenon particularly in patients with diabetes mellitus (DM). However, whether the extent of LVR is associated with poor prognostic outcome with or without DM after STEMI in the modern era of reperfusion therapy has not been elucidated. This was a single-center retrospective observational study. Altogether, 243 patients who were diagnosed as having STEMI between January 2016 and March 2019, and examined with echocardiography at baseline (at the time of index admission) and mid-term (from 6 to 11 months after index admission) follow-up were included and divided into the DM (n = 98) and non-DM groups (n = 145). The primary outcome was major adverse cardiovascular events (MACEs) defined as the composite of all-cause death, heart failure (HF) hospitalization, and non-fatal myocardial infarction. The median follow-up duration was 621 days (interquartile range: 304-963 days). The DM group was significantly increased the rate of MACEs (P = 0.020) and HF hospitalization (P = 0.037) compared with the non-DM group, despite of less LVR. Multivariate Cox regression analyses revealed that the patients with DM after STEMI were significantly associated with MACEs (Hazard ratio [HR] 2.79, 95% confidence interval [CI] 1.20-6.47, P = 0.017) and HF hospitalization (HR 3.62, 95% CI 1.19-11.02, P = 0.023) after controlling known clinical risk factors. LVR were also significantly associated with MACEs (HR 2.44, 95% CI 1.03-5.78, P = 0.044) and HF hospitalization (HR 3.76, 95% CI 1.15-12.32, P = 0.029). The patients with both DM and LVR had worse clinical outcomes including MACEs and HF hospitalization, suggesting that it is particularly critical to minimize LVR after STEMI in patients with DM.

Usefulness of 500-m walk electrocardiogram test on clinical outcomes in patients with ST-segment elevation myocardial infarction.

The current Japanese guideline for ST-segment elevation myocardial infarction (STEMI) recommends 500-m walk electrocardiogram (ECG) test for patients with STEMI during hospitalization. However, little is known regarding the association between acute phase 500-m walk ECG test and clinical outcomes. The purpose of this study was to investigate the association between 500-m walk ECG test and mid-term clinical outcomes in patients with STEMI. A total of 313 STEMI patients who underwent primary percutaneous coronary interventions were included, and were divided into the successful 500-m group (n = 263) and the unsuccessful 500-m group (n = 50). The primary endpoint was the major adverse cardiovascular events (MACE), which were defined as the composite of all cause death, acute myocardial infarction, readmission for heart failure, and ischemia-driven target vessel revascularization (TVR). During the follow-up period (median 223 days), a total of 55 MACE were observed. The log-rank test revealed that MACE, all cause death, readmission for heart failure, and ischemia-driven TVR were more frequently observed in the unsuccessful 500-m group than the successful 500-m group. In the multivariate Cox proportional hazard model, the unsuccessful 500-m walk ECG test was significantly associated with MACE (OR 5.62, 95% CI 3.08-10.08, P < 0.01) after controlling confounding factors such as age, and serum creatinine levels. In conclusion, the unsuccessful 500-m walk ECG test was significantly associated with poor mid-term outcomes in patients with STEMI. Our results suggest the usefulness of 500-m walk ECG test to stratify the high-risk group from patients with STEMI.

Association of Baseline Anemia with Mid-Term Clinical Outcomes in Patients Who Underwent Trans-Radial Primary Percutaneous Coronary Intervention.

Radial access is recommended for primary percutaneous coronary intervention (PCI), because it has fewer bleeding complications than trans-femoral PCI. However, even if trans-radial PCI is chosen, patients with ST-elevation myocardial infarction (STEMI) presenting with anemia on admission might have poor clinical outcomes. The aim of this retrospective study was to investigate whether anemia on admission was associated with mid-term clinical outcomes in patients who underwent trans-radial primary PCI. The primary endpoint was a composite of all-cause death, recurrent acute myocardial infarction, and readmission for heart failure. A total of 288 consecutive patients with STEMI who underwent trans-radial primary PCI were divided into an anemia group (n = 79) and a non-anemia group (n = 209). The median follow-up duration was 301 days. The anemia group was significantly older than the non-anemia group (77.3 ± 11.9 versus 64.4 ± 12.7 years, respectively; P < 0.001). There were significantly more females in the anemia group than in the non-anemia group (36.7% versus 14.4%, respectively; P < 0.001). Kaplan-Meier analysis revealed that the composite outcome-free survival was significantly worse in the anemia group than in the non-anemia group (P < 0.001). Multivariate Cox hazard model analysis revealed that hemoglobin levels on admission were significantly associated with the composite outcome (per 1 g/dL increase: hazard ratio 0.76, 95% confidence interval 0.66-0.88, P < 0.001) after controlling for confounding factors. In conclusion, baseline anemia was significantly associated with poor clinical outcomes. Patients with STEMI presenting with anemia should be managed carefully, even if trans-radial primary PCI is chosen.

Comparison of Clinical Characteristics of Acute Myocardial Infarction Between Young (< 55 Years) and Older (55 to < 70 Years) Patients.

Although the incidence of acute myocardial infarction (AMI) has been decreasing in the elderly, it has been increasing in the young, especially in Japan. A social impact of AMI would be greater in the young, because loss of the young directly influences social activities such as business, child-raising, and tax payment. The aim of this study was to identify the specific characteristics of young AMI patients. We retrospectively included 408 consecutive AMI patients < 70 years of age, divided into a young group (< 55 years: n = 136) and an older group (55 to < 70 years: n = 272). The prevalence of overweight was greater in the young group (58.5%) than in the older group (40.7%) (P = 0.001). The frequency of current smokers was higher in the young group (67.6%) than in the older group (44.9%) (P < 0.001). Although the prevalence of hypertension was lower in the young group (66.7%) than in the older group (77.2%) (P = 0.017), that of untreated hypertension was greater in the young group (40.4%) than in the older group (27.2%) (P = 0.007). Furthermore, the prevalence of untreated dyslipidemia was greater in the young group (45.0%) than in the older group (26.6%) (P < 0.001). In conclusion, the young AMI patients had more modifiable risk factors such as obesity, smoking, untreated hypertension, and untreated dyslipidemia than the older patients. There is an unmet medical need for the prevention of AMI in the young generation.

Factors Associated with In-Hospital Death in Patients with Killip Class 3 Acute Myocardial Infarction.

The clinical outcomes in acute myocardial infarction (AMI) patients with Killip class 3 are often inconsistent with those in the literature, and the factors associated with poor outcomes have not been sufficiently investigated. The purpose of this study was to identify factors associated with in-hospital death in AMI patients with Killip class 3. We included 205 AMI patients with Killip class 3, and divided them into a survived group (n = 189) and in-hospital death group (n = 16). The primary objective was to identify factors associated with in-hospital death using multivariate analysis. Age was significantly younger in the survived group than in the in-hospital death group (73.1 ± 11.2 versus 83.2 ± 6.2 years, P < 0.001). Systolic blood pressure (SBP) was significantly higher in the survived group than in the in-hospital death group (150.0 ± 31.2 versus 124.8 ± 25.3 mmHg, P = 0.002). The prevalence of TIMI thrombus grade ≥ 2 was significantly greater in the in-hospital death group than in the survived group (56.3 versus 22.2%, P = 0.005). In multivariate logistic regression analysis, in-hospital death was significantly associated with age [odds ratio (OR) 1.168, 95% confidence interval (CI) 1.061-1.287, P = 0.002] and TIMI thrombus grade ≥ 2 (versus ≤ 1: OR 5.743, 95% CI 1.717-19.214, P = 0.005), and inversely associated with SBP on admission (per 10 mmHg increase: OR 0.764, 95% CI 0.613-0.953, P = 0.017). In conclusion, in-hospital death was associated with age and coronary thrombus burden, and was inversely associated with SBP on admission in patients with Killip class 3. It may be important to recognize these high risk features to improve the clinical outcomes of patients with Killip class 3.

Comparison of Clinical Outcomes of Acute Myocardial Infarction Between Prasugrel and Clopidogrel.

The rapid introduction of dual antiplatelet therapy (DAPT) is important for patients with acute myocardial infarction (AMI). The risks and benefits of reduced-dose prasugrel (20 mg loading and 3.75 mg maintenance) over clopidogrel have not been fully discussed. The purpose of this study was to compare the 90-days clinical outcomes of AMI between prasugrel-based DAPT and clopidogrel-based DAPT. We included 534 AMI patients and divided them into the clopidogrel group (n = 330) and the prasugrel group (n = 204). The primary endpoint was the total ischemic events and total bleeding events. In all, 52 ischemic events and 35 bleeding events were observed during the study period. The total ischemic events were similar between the clopidogrel and the prasugrel groups (P = 0.385). The total bleeding events were similar between the clopidogrel and the prasugrel groups (P = 0.125). The multivariate Cox hazard analysis showed that prasugrel was not associated with the total ischemic events (hazard ratio (HR) 0.955, 95% confidence interval (CI) 0.499-1.829, P = 0.890) and was not associated with the total bleeding events after controlling confounding factors (HR 0.972, 95% CI 0.528-1.790, P = 0.927). In conclusion, as compared to clopidogrel, the reduced dose of prasugrel was not associated with the excess risk of bleeding or the excess risk of ischemic events. Our real-world data support the current regimen of prasugrel for AMI patients who underwent primary percutaneous coronary intervention.