Takahiro Nakashima

Prognostic impact of spontaneous coronary artery dissection in young female patients with acute myocardial infarction: A report from the Angina Pectoris–Myocardial Infarction Multicenter Investigators in Japan

BACKGROUND We sought to compare the prognosis of patients with spontaneous coronary artery dissection (SCAD) and atherosclerosis as the cause of acute myocardial infarction (AMI), especially in young females. METHODS AND RESULTS A total of 20,195 patients with AMI at 20 institutions between 2000 and 2013 were retrospectively studied. Major adverse cardiac event (MACE: cardiac death, AMI or urgent revascularization) was the endpoint. The overall prevalence of SCAD was 0.31% (n=63; female, 94%). SCAD developed following emotional stress in 29% of patients. Revascularization was performed in 56% (35 of 63 patients), and SCAD recurrence developed in the originally involved vessel in 6 of 35 patients with revascularization, compared to none among 28 patients after conservative therapy (p=0.002). We compared the clinical characteristics of young female AMI patients aged ≤50years in the SCAD (n=45) and no-SCAD groups (atherosclerotic AMI, n=55). During a median follow-up of 50months, SCAD recurred in 27% of patients, of which 42% was in the first 30days. Kaplan-Meier analysis showed a significantly higher incidence of MACE in the SCAD group compared to the no-SCAD group (hazard ratio, 6.91; 95% confidence interval, 2.5 to 24.3; p<0.001), although the rate of successful percutaneous coronary intervention for SCAD was as high as 92%. CONCLUSIONS Young female patients with SCAD represent a high-risk subgroup of patients with AMI and require close follow-up.

Coronary Artery Ectasia Predicts Future Cardiac Events in Patients With Acute Myocardial InfarctionHighlights

Objective— Coronary artery ectasia (CAE) is an infrequently observed vascular phenotype characterized by abnormal vessel dilatation and disturbed coronary flow, which potentially promote thrombogenicity and inflammatory reactions. However, whether or not CAE influences cardiovascular outcomes remains unknown. Approach and Results— We investigated major adverse cardiac events (MACE; defined as cardiac death and nonfatal myocardial infarction [MI]) in 1698 patients with acute MI. The occurrence of MACE was compared in patients with and without CAE. CAE was identified in 3.0% of study subjects. During the 49-month observation period, CAE was associated with 3.25-, 2.71-, and 4.92-fold greater likelihoods of experiencing MACE (95% confidence interval [CI], 1.88–5.66; P<0.001), cardiac death (95% CI, 1.37–5.37; P=0.004), and nonfatal MI (95% CI, 2.20–11.0; P<0.001), respectively. These cardiac risks of CAE were consistently observed in a multivariate Cox proportional hazards model (MACE: hazard ratio, 4.94; 95% CI, 2.36–10.4; P<0.001) and in a propensity score–matched cohort (MACE: hazard ratio, 8.98; 95% CI, 1.14–71.0; P=0.03). Despite having a higher risk of CAE-related cardiac events, patients with CAE receiving anticoagulation therapy who achieved an optimal percent time in target therapeutic range, defined as ≥60%, did not experience the occurrence of MACE (P=0.03 versus patients with percent time in target therapeutic range <60% or without anticoagulation therapy). Conclusions— The presence of CAE predicted future cardiac events in patients with acute MI. Our findings suggest that acute MI patients with CAE are a high-risk subset who might benefit from a pharmacological approach to controlling the coagulation cascade.

Validation of the Coronary Artery Bypass Graft SYNTAX Score (Synergy Between Percutaneous Coronary Intervention With Taxus) as a Prognostic Marker for Patients With Previous Coronary Artery Bypass Graft Surgery After Percutaneous Coronary Intervention

Background—The efficacy and prognosis of percutaneous coronary intervention (PCI) as secondary revascularization in patients with previous coronary artery bypass graft surgery remain uncertain. Methods and Results—We retrospectively evaluated 434 consecutive patients with previous coronary artery bypass graft surgery hospitalized for PCI between 2004 and 2011 (men 84%, age 71 (interquartile range, 66–76) years) and calculated the coronary artery bypass graft Synergy Between Percutaneous Coronary Intervention With Taxus score (CSS) before (baseline CSS) and after PCI (post-PCI CSS). Patients were divided into 2 groups based on median post-PCI CSS: low-score (⩽23; n=217) and high-score groups (>23; n=217). Major adverse cardiovascular events (MACE) were defined as the composite of cardiovascular death, myocardial infarction, and unplanned repeat revascularization for myocardial ischemia. The median baseline and post-PCI CSS were 30 (interquartile range, 21–40) and 23 (interquartile range, 14.5–33.5), respectively. During a median follow-up of 69 months, the prevalence of MACE and cardiac death differed significantly between the 2 post-PCI CSS groups (MACE: low, 13.8%; high, 28.6%; P<0.001; cardiac death: low, 6.2%; high, 16.7%; P=0.002). In multivariable analysis, the high post-PCI CSS divided by the median was associated with substantially greater cumulative MACE (hazard ratio, 2.09; 95% confidence interval, 1.31–3.34; P=0.002) and cardiac death (hazard ratio, 2.02; 95% confidence interval, 1.03–3.98; P=0.042) compared with the low post-PCI CSS. Net reclassification improvement analysis revealed that post-PCI CSS resulted in significantly improved prediction of MACE and cardiac death compared with baseline CSS. Conclusions—In this external validation study, the CSS was a potential prognostic factor after subsequent PCI, even for previous coronary artery bypass graft surgery patients.

Utility of High-Resolution Magnetocardiography to Predict Later Cardiac Events in Nonischemic Cardiomyopathy Patients With Normal QRS Duration

BACKGROUND Nonischemic dilated cardiomyopathy (NIDCM) patients, even those with a narrow QRS, are at increased risk for major adverse cardiac events (MACE). We hypothesized that 64-channel magnetocardiography (MCG) would be useful to detect prognostic left intraventricular disorganized conduction (LiDC) by overcoming the limitations of fragmented QRS (fQRS, qualitative definitions, low specificity) and late potential (abnormality undetectable in earlier QRS).Methods and Results:We evaluated LiDC on MCG, defined as significant deviation from a global clockwise left ventricular (LV) activation pattern, and conventional noninvasive predictors of MACE, including fQRS and late potential, in 51 NIDCM patients with narrow QRS (LV ejection fraction, 22±7%; QRS duration, 99±11 ms). MACE was defined as cardiac death, lethal ventricular arrhythmias, or LV assist device (LVAD) implantation. LiDC was present in 22 patients. Baseline characteristics were comparable between patients with and without LiDC, except for the ratio of positive late potential. During a mean follow-up of 2.9 years, MACE developed in 16 NIDCM patients (3 cardiac deaths, 9 lethal ventricular arrhythmias, and 4 LVAD). MACE was more incident in patients with LiDC (13/22) than in those without (3/29, P<0.001). Multivariate analysis revealed LiDC, but not fQRS or late potential, as the strongest independent predictor of MACE (hazard ratio 4.28, 95% confidence interval 1.30-19.39, P=0.015). CONCLUSIONS MCG accurately depicts LiDC, a promising noninvasive predictor of MACE in patients with NIDCM and normal QRS.

Achieving the earliest possible reperfusion in patients with acute coronary syndrome: a current overview

Acute coronary syndrome (ACS) remains one of the leading causes of mortality worldwide. Appropriate management of ACS will lead to a lower incidence of cardiac arrest. Percutaneous coronary intervention (PCI) is the first-line treatment for patients with ACS. PCI techniques have become established. Thus, the establishment of a system of health care in the prehospital and emergency department settings is needed to reduce mortality in patients with ACS. In this review, evidence on how to achieve earlier diagnosis, therapeutic intervention, and decision to reperfuse with a focus on the prehospital and emergency department settings is systematically summarized.The purpose of this review is to generate current, evidence-based consensus on scientific and treatment recommendations for health care providers who are the initial points of contact for patients with signs and symptoms suggestive of ACS.

Suboptimal Post-Procedural TIMI Flow in NSTEMI

T he goal of primary percutaneous coronary intervention (PCI) for patients with ST-segment elevation myocardial infarction (STEMI) is final Thrombolysis in Myocardial Infarction (TIMI) grade 3 in the infarct-related artery, which means improved tissue perfusion. However, it is not always possible to obtain final TIMI3 after adequate PCI for a culprit coronary artery in patients with acute myocardial infarction (AMI). It is well known that post-PCI TIMI flow is related to longterm prognosis in patients with STEMI. On the other hand, the impact of suboptimal post-PCI coronary flow defined as TIMI 2 on long-term prognosis in patients with non (N)-STEMI has not been fully investigated.