Hiroki Ikenaga

Assessment of outcomes and differences between in- and out-of-hospital cardiac arrest patients treated with cardiopulmonary resuscitation using extracorporeal life support☆

AIM Cardiopulmonary resuscitation (CPR) using extracorporeal life support (ECLS) for in-hospital cardiac arrest (IHCA) patients has been assigned a low-grade recommendation in current resuscitation guidelines. This study compared the outcomes of IHCA and out-of-hospital cardiac arrest (OHCA) patients treated with ECLS. METHODS A total of 77 patients were treated with ECLS. Baselines characteristics and outcomes were compared for 38 IHCA and 39 OCHA patients. RESULTS The time interval between collapse and starting ECLS was significantly shorter after IHCA than after OHCA (25 (21-43)min versus 59 (45-65)min, p<0.001). The weaning rate from ECLS (61% versus 36%, p=0.03) and 30-day survival (34% versus 13%, p=0.03) were higher for IHCA compared with OHCA patients. IHCA patients had a higher rate of favourable neurological outcome compared to OHCA patients, but the difference was not statistically significant (26% versus 10%, p=0.07). Kaplan-Meier analysis showed improved 30-day and 1-year survival for IHCA patients treated with ECLS compared to OHCA patients who had ECLS. However, multivariate stepwise Cox regression model analysis indicated no difference in 30-day (odds ratio 0.94 (95% confidence interval 0.68-1.27), p=0.67) and 1-year survival (0.99 (0.73-1.33), p=0.95). CONCLUSION CPR with ECLS led to more favourable patient outcomes after IHCA compared with OHCA in our patient group. The difference in outcomes for ECLS after IHCA and OHCA disappeared after adjusting for patient factors and the time delay in starting ECLS.

Prevalence of incidental coronary artery disease in tako-tsubo cardiomyopathy.

ObjectiveEarlier studies have often required the absence of obstructive coronary artery disease (CAD) as the criteria. However, it is probable that patients with tako-tsubo cardiomyopathy have an incidental CAD because most patients are elderly. We assessed the prevalence of incidental CAD. MethodsWe reviewed coronary angiograms of 97 Japanese patients with tako-tsubo cardiomyopathy. A wrapped left anterior descending artery (LAD) was defined as a LAD that perfused at least one-quarter of the inferior wall of the left ventricle in the 30° right anterior oblique projection. ResultsTen patients (10%) had definitively incidental CAD defined as greater than 75% reduction in the luminal diameter of the major epicardial coronary artery. All patients had ST-segment elevation, and five patients had T-wave inversion on admission. Nine patients had single vessel disease, and one patient had double vessel disease. Six patients had CAD in the nonwrapped LAD, and they were judged to be definitively incidental. Three patients had CAD in the left circumflex artery, and two patients had CAD in the right coronary artery. ConclusionThis study showed that incidental CAD was found in 10% of Japanese patients with tako-tsubo cardiomyopathy. In patients with CAD in the LAD, it should be carefully judged whether the CAD causes left ventricular apical ballooning to avoid performing coronary revascularization unnecessarily.

Presentation of Tako-tsubo Cardiomyopathy in Men and Women

Recent studies have demonstrated that stress‐induced Tako‐tsubo cardiomyopathy is likely to occur in elderly female patients.

Who benefits most from mild therapeutic hypothermia in coronary intervention era? A retrospective and propensity-matched study

IntroductionThe aim of the present study was to investigate the impact of the time interval from collapse to return of spontaneous circulation (CPA-ROSC) in cardiac arrest patients and the types of patients who will benefit from therapeutic hypothermia.MethodsFour hundred witnessed adult comatose survivors of out-of-hospital cardiac arrest of cardiac etiology were enrolled in the study. The favorable neurological outcome was defined as category 1 or 2 on the five-point Pittsburgh cerebral performance scale at the time of hospital discharge. A matching process based on the propensity score was performed to equalize potential prognostic factors in the hypothermia and normothermia groups, and to formulate a balanced 1:1 matched cohort study.ResultsThe rate of favorable neurological outcome was higher (P < 0.05) in the hypothermia group (n = 110) than in the normothermia group in patients with CPA-ROSC of 15 to 20 minutes (64% vs. 17%), 20 to 25 minutes (70% vs. 8%), 25 to 30 minutes (50% vs. 7%), 35 to 40 minutes (27% vs. 0%) and 40 to 45 minutes (29% vs. 2%). A similar association was observed in a propensity-matched cohort, but the differences were not significant. There was no significant difference in the rate of favorable neurological outcome between the hypothermia-matched group and the normothermia-matched group. In the patients whose CPA-ROSC was greater than 15 minutes, however, the rate of favorable neurological outcome was higher in the hypothermia-matched group than in the normothermia-matched group (27% vs. 4%, P < 0.001). In multivariate analysis, the CPA-ROSC was an independent predictor of favorable neurological outcome (every 1 minute: odds ratio = 0.89, 95% confidence interval = 0.85 to 0.92, P < 0.001).ConclusionsThe CPA-ROSC is an independent predictor of neurological outcome. Therapeutic hypothermia is more beneficial in comatose survivors of cardiac arrest with CPA-ROSC greater than 15 minutes.

Assessment of medications in patients with tako-tsubo cardiomyopathy

BACKGROUND Tako-tsubo cardiomyopathy has been gradually recognized worldwide. However, medications for the prevention remain not to be investigated in part because the precise mechanism is unclear. We sought to examine medications before the onset of tako-tsubo cardiomyopathy, and to prove the limitation of these medications for the prevention. METHODS AND RESULTS This study consisted of 21 patients with tako-tsubo cardiomyopathy who received one or more medications for hypertension or suspected angina pectoris. Each patient was assessed with history, medications, coronary angiography and left ventriculography. All patients but 1 were female, and age ranged 41 to 87 years (73+/-11 years). Twelve patients received calcium channel blockers, 7 patients received nitrates, and one patient received beta blocker. Three patients received angiotensin coverting enzyme inhibitors, and 4 patients received angiotensin II receptor blockers. One patient died of serious pneumonia, but there was no patient who died of tako-tsubo cardiomyopathy itself. During the 3 year follow-up, one patient receiving angiotensin receptor blocker had the recurrence of tako-tsubo cardiomyopathy due to recurrent epileptic seizure. CONCLUSIONS Tako-tsubo cardiomyopathy can occur despite treatment with calcium channel blockers, nitrates or beta-blockers, suggesting limitation of these medications to prevent tako-tsubo cardiomyopathy.

Longitudinal extent of lipid pool assessed by optical coherence tomography predicts microvascular no-reflow after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

BACKGROUND Distal embolization during percutaneous coronary intervention (PCI) may deteriorate microvascular reperfusion in patients with ST-elevation myocardial infarction (STEMI). Reperfusion at the coronary microvascular level is important for STEMI and culprit plaque is associated with distal embolization and microvascular reperfusion. ST-segment resolution (ST-R) in the electrocardiogram reflects microvascular reperfusion after primary PCI. Longitudinal extent of lipid pool assessed by optical coherence tomography (OCT) may predict the risk of failure of microvascular reperfusion after primary PCI. METHODS AND RESULTS This study consisted of 39 patients with STEMI who underwent primary PCI within 24h after the onset of chest pain. Immediately after thrombectomy, OCT was performed and length of lipid pool was measured. Microvascular reperfusion after primary PCI was assessed by ST-R, which was defined as >50% decrease in ST elevation at 1h after primary PCI. There were 23 patients with ST-R and 16 patients without ST-R, with no significant difference in baseline clinical and angiographical variables between the 2 groups. Final thrombolysis in myocardial infarction 3 flow was obtained in all of the patients. Peak creatine kinase was significantly higher in the ST-R (-) group than in the ST-R (+) group (p=0.01). Length of lipid pool was 10.1 ± 2.8mm in the ST-R (-) group and 7.8 ± 3.2mm in the ST-R (+) group (p=0.02). In receiver operating characteristics curve assessing the ability of length of lipid pool to predict ST-R, area under the curve was 0.74 (p=0.02). Length of lipid pool >9.0mm best predicted the absence of ST-R with sensitivity 88% and specificity 78%. CONCLUSIONS These findings suggest that length of lipid pool estimated by OCT may predict microvascular no-reflow after primary PCI.

History of diabetes mellitus as a neurologic predictor in comatose survivors of cardiac arrest of cardiac origin treated with mild hypothermia.

AIM To investigate the impact of a history of diabetes mellitus on the neurologic outcome in comatose survivors of cardiac arrest of cardiac origin treated with mild hypothermia. METHODS A prospective observational study was performed between September 2003 and July 2008. Eighty comatose survivors of cardiac arrest of cardiac origin were treated with mild hypothermia. Neurologic outcome at the time of hospital discharge, 30-day survival, and complications were assessed. RESULTS Twenty-four of the 80 patients (30%) had a history of diabetes. The rate of favorable neurologic outcome was significantly lower in diabetic (17%) than in nondiabetic patients (46%) (p=0.01). The rate of 30-day survival was lower in diabetic (33%) than in nondiabetic patients (54%), but the difference was not significant (p=0.10). Multivariate analysis suggested that a history of diabetes was an independent predictor of unfavorable neurologic outcome (odds ratio 7.00, 95% confidence interval 1.42-46.19, p=0.03), but not for 30-day survival. There was no significant difference in the prevalence of complications. CONCLUSION A history of diabetes is associated with poor neurologic outcome in comatose survivors of cardiac arrest treated with mild hypothermia.

Therapeutic hypothermia after out-of-hospital cardiac arrest due to Brugada syndrome

A 56-year-old man was admitted to our hospital after successful resuscitation for out-of-hospital cardiac arrest. Electrocardiogram on admission showed right bundle branch block and ST segment elevation in leads V1-3. Subsequent intravenous infusion of isoproterenol rapidly resolved ST segment elevation, suggesting Brugada syndrome. Therapeutic hypothermia, that was performed with a target temperature of 34.0 degrees C did not induce ST segment elevation in leads V1-3. The J-ST segment elevation rather became much more normal, suggesting a beneficial effect of mild therapeutic hypothermia. Serial ECG showed the temporal variation of ST segment elevation, and pilsicainide challenge test showed the occurrence of ST segment elevation, confirming the diagnosis of Brugada syndrome. Clinical observation suggested that mild therapeutic hypothermia reversed the Brugada phenotype through the prevention of fever as well as being indicated for cerebral protection after cardiac arrest. In conclusion, therapeutic hypothermia with a temperature of 34.0 degrees C can be used safely in Brugada syndrome.

Coronary angioscopic findings 9 months after everolimus-eluting stent implantation compared with sirolimus-eluting stents

OBJECTIVES We assessed angioscopic findings after everolimus-eluting stents (EES) implantation, compared with sirolimus-eluting stents (SES). BACKGROUND Coronary angioscopy (CAS) provides an opportunity to assess neointimal coverage over stent struts, thrombus, and plaque color by direct visualization. CAS is a useful tool for evaluating stent struts after drug-eluting stent implantation. Angioscopic findings after EES implantation have not been reported before. METHODS We performed CAS in 23 patients who were treated with EES and 41 patients with SES. CAS was performed 8.5 months after stent implantation. We assessed neointimal coverage, thrombus, and plaque color. We classified neointimal coverage in 4 grades: grade 0=struts were completely exposed; grade 1=struts were visible with dull light reflexion; grade 2=there was no light reflexion from slightly visible struts; grade 3=struts were completely covered. RESULTS There was no significant difference in minimum, maximum, dominant grade of neointimal coverage, and heterogeneity index between EES and SES. Thrombus was less frequently observed in EES than SES (4% vs 29%, p=0.02). When we divided study patients into acute coronary syndrome (ACS) or stable angina pectoris (SAP), there was a tendency toward less thrombus in EES than SES, in both ACS and SAP. Maximum color grade of the plaques was less advanced in EES than SES (p<0.01). Yellow plaques of grade 2 or 3 were less frequent in EES than SES (35% vs 76%, p<0.01). CONCLUSIONS This study suggested that EES were associated with lower risk of thrombus formation than SES.

Influence of left ventricular geometry on thallium-201 gated single-photon emission tomographic findings in patients with known or suspected coronary artery disease.

BackgroundRecent studies have shown good correlations between echocardiography and Tl-201 gated single-photon emission computed tomography (SPECT) for the assessment of left ventricular volumes and ejection fraction. We assessed how left ventricular geometry affected correlations between these values measured by the 2 methods in patients with known or suspected coronary artery disease.Methods and resultsThere were 109 patients with normal left ventricular geometry, 20 patients with concentric remodeling, 32 patients with eccentric hypertrophy and 28 patients with concentric hypertrophy. In all 4 groups, there were good correlations between end-diastolic volume (EDV) and end-systolic volume (ESV) values measured by echocardiography and quantitative gated SPECT (QGS). EDV and ESV values measured by QGS were significantly underestimated than those measured by echocardiography except for ESV in eccentric hypertrophy. In all 4 groups, ejection fraction (EF) value measured by echocardiography significantly correlated with that measured by QGS, but Bland–Altman plot showed a proportional error. EF value measured by QGS was likely to be overestimated when EF value increased from the median value, and to be underestimated when EF value decreased from the median value especially in concentric remodeling.ConclusionsTl-201 gated SPECT is a useful tool for the assessment of left ventricular volumes and function, but it requires methodological considerations according to left ventricular geometry.