Yoshihiko Seino

Appearance of Lipid-Laden Intima and Neovascularization After Implantation of Bare-Metal Stents: Extended Late-Phase Observation by Intracoronary Optical Coherence Tomography

OBJECTIVES We examined the neointimal characteristics of bare-metal stents (BMS) in extended late phase by the use of optical coherence tomography (OCT). BACKGROUND The long-term neointimal features after BMS implantation have not yet been fully characterized. METHODS Intracoronary OCT observation of BMS segments was performed during the early phase (<6 months, n = 20) and late phase (>or=5 years, n = 21) after implantation. Internal tissue of the BMS was categorized into normal neointima, characterized by a signal-rich band without signal attenuation, or lipid-leaden intima, with marked signal attenuation and a diffuse border. In addition, the presence of disrupted intima and thrombus was evaluated. Neovascularization was defined as small vesicular or tubular structures, and the location of the microvessels was classified into peristent or intraintima. RESULTS Normal neointima proliferated homogeneously, and lipid-laden intima was not observed in the early phase. In the late phase, lipid-laden intima, intimal disruption, and thrombus frequently were found in comparison with the early phase (67% vs. 0%, 38% vs. 0%, and 52% vs. 5%, respectively; p < 0.05). Persistent neovascularization demonstrated a similar incidence between the 2 phases. The appearance of intraintima neovascularization was more prevalent in the late phase than the early phase (62% vs. 0%, respectively; p < 0.01) and in segments with lipid-laden intima than in nonlipidic segments (79% vs. 29%, respectively; p = 0.026). CONCLUSIONS This OCT study suggests that neointima within the BMS often transforms into lipid-laden tissue during an extended period of time and that expansion of neovascularization from peristent to intraintima contributes to atherosclerotic progression of neointima.

Clinical significance of elevated levels of cardiac troponin T in patients with chronic heart failure

Cardiac troponin T, measured by second-generation assay, is a highly sensitive and specific marker of minor myocardial damage. Cardiac troponin T was elevated in patients with severe chronic heart failure; it identifies those with latent and progressive myocardial damage and those who are at increased risk of cardiac events.

Use of cytosolic and myofibril markers in the detection of ongoing myocardial damage in patients with chronic heart failure.

PURPOSE Measurement of serum levels of cytosolic and myofibril components of cardiac tissue could indicate ongoing myocardial damage in patients with chronic heart failure. METHODS We correlated serum levels of a cytosolic marker (heart-type fatty acid-binding protein) and a myofibril marker (troponin T) with the severity of symptoms (based on the New York Heart Association [NYHA] class), neurohumoral derangement, and subsequent cardiac events in 56 patients with chronic heart failure. RESULTS Mean (+/- SD) levels of heart-type fatty acid-binding protein were greater in patients with NYHA class III or IV heart failure (9.9 +/- 5.2 ng/mL) than in those with NYHA class II (4.9 +/- 1.9 ng/mL, P <0.0001). Detection of troponin T (> or =0.02 ng/mL) was also more common in patients with worse heart failure (81% [13/16] in class III or IV vs. 43% [17/40] in class II, P = 0.02). Significant correlations were found between heart-type fatty acid-binding protein levels and plasma levels of A-type natriuretic peptide (r = 0.45, P = 0.0004), B-type natriuretic peptide (r = 0.66, P <0.0001), and norepinephrine (r = 0.36, P = 0.006). Male sex (hazard ratio [HR] = 5.0; 95% confidence interval [CI]: 1.3 to 19), detectable troponin T levels (HR = 7.0; 95% CI: 1.1 to 44), heart-type fatty acid-binding protein (HR = 2.6 per 3.9-ng/mL increase; 95% CI: 1.1 to 6.5), and left ventricular ejection fraction (HR = 3.6 per 15% decrease; 95% CI: 1.2 to 11) were independently associated with subsequent cardiac events (8 deaths or 10 readmissions because of worsening heart failure). CONCLUSION Heart-type fatty acid-binding protein and troponin T are markers of ongoing myocardial damage, and are associated with subsequent cardiac events in patients with chronic heart failure.

Use of a whole blood rapid panel test for heart-type fatty acid-binding protein in patients with acute chest pain: comparison with rapid troponin T and myoglobin tests.

PURPOSE We sought to determine the clinical utility of a newly developed qualitative test to measure heart-type fatty acid-binding protein levels in blood for the early identification of myocardial infarction. METHODS We measured heart-type fatty acid-binding protein levels in 371 consecutive patients with acute chest pain and suspected myocardial infarction, and compared the performance of this test with those of troponin T and myoglobin tests. Levels of heart-type fatty acid-binding protein >or=6.2 ng/mL were considered as positive results. RESULTS A final diagnosis of acute myocardial infarction was made in 181 patients (49%). Of the 68 patients who presented within 2 hours of the onset of symptoms, 37 (54%) had a final diagnosis of myocardial infarction. The sensitivity of the rapid heart-type fatty acid-binding protein test was 89% (33/37), significantly higher than for troponin T (22% [8/37]; P<0.001) and myoglobin (38% [14/37]; P<0.001). However, the specificity of troponin T (94% [29/31]) was significantly better than for heart-type fatty acid-binding protein (52% [16/31]; P= 0.002) within 2 hours. The area under the receiver operating characteristic curve for heart-type fatty acid-binding protein levels was greater than that for myoglobin (0.72 vs. 0.61, P = 0.01) among patients who presented within 2 hours. CONCLUSION A novel whole blood rapid heart-type fatty acid-binding protein test can be useful in the early evaluation of patients who present with acute chest pain.

Association between high-sensitivity cardiac troponin T levels and the predicted cardiovascular risk in middle-aged men without overt cardiovascular disease

BACKGROUND A slight elevation of cardiac troponin T (TnT) levels in the circulating blood can be detected by the recently developed, high-sensitivity TnT (hsTnT) assay. However, it remains unclear whether a slight elevation of hsTnT is associated with an increased cardiovascular risk in subjects without overt cardiovascular disease (CVD). METHODS The serum hsTnT levels were measured in a work site-based population of 1,072 middle-aged males (mean age 44 years) without any history or presence of CVD. The lower detection limit of the hsTnT assay used in the present study was 0.002 ng/mL. The association of the hsTnT levels with cardiovascular risk factors and the predicted CVD risk, as determined by the Framingham CVD risk prediction score, were examined. RESULTS Detectable hsTnT levels were seen in 867 subjects (80.9%). The highest value of the hsTnT was 0.020 ng/mL. Among various cardiovascular risk factors, age, blood pressure, estimated glomerular filtration rate, current smoking, and left ventricular hypertrophy were independent determinants of hsTnT levels. The odds ratio for a high predicted CVD risk (10-year risk > or =20%) in the highest tertile of hsTnT (> or =0.005 ng/mL) in comparison to the lowest tertile (< or =0.002 ng/mL) was 3.98 (95% CI 1.72-9.24, P = .001) after adjusting for multiple potential confounders. CONCLUSIONS The present study showed the hsTnT levels to be significantly associated with several cardiovascular risk factors and the predicted CVD risk in middle-aged men without overt CVD, thus suggesting the usefulness of measuring hsTnT to identify high-risk subjects in the primary prevention of CVD.

Long-Term Follow-Up Evaluation After Sirolimus-Eluting Stent Implantation by Optical Coherence Tomography: Do Uncovered Struts Persist?

To the Editor: Presently, occurrence of late stent thrombosis (LST) after drug-eluting stent implantation is a major clinical concern. Although LST is an infrequent complication, LST can lead to serious results. A long-term follow-up study revealed recently that LST occurs at a constant rate of 0.6

Comparison of neointimal coverage by optical coherence tomography of a sirolimus-eluting stent versus a bare-metal stent three months after implantation.

No detailed data regarding neointimal coverage of bare-metal stents (BMSs) at 3 months after implantation was reported to date. This investigation was designed to evaluate the neointimal coverage of BMSs compared with sirolimus-eluting stents (SESs) using optical coherence tomography. A prospective optical coherence tomographic follow-up examination was performed 3 months after stent implantation for patients who underwent BMS (n = 16) or SES implantation (n = 24). Neointimal hyperplasia (NIH) thickness on each stent strut and percentage of NIH area in each cross section were measured. Malapposition of stent struts to the vessel wall and the existence of in-stent thrombi were also evaluated. There were 5,076 struts of SESs and 2,875 struts of BMSs identified. NIH thickness and percentage of NIH area in the BMS group were higher than in the SES group (351 +/- 248 vs 31 +/- 39 mum; p <0.0001; 45.0 +/- 14% vs 10.0 +/- 4%; p <0.0001, respectively). The frequency of uncovered struts was higher in the SES group than the BMS group (15% vs 0.1%; p <0.0001). Malapposed struts were observed more frequently in the SES group than the BMS group (15% vs 1.1%; p <0.0001). In conclusion, there was no difference in incidence of in-stent thrombus between the 2 groups (14% vs 0%; p = 0.23). The present study showed almost all BMS struts to be well covered at a 3-month follow-up, suggesting that patients receiving BMS stents may not require dual-antiplatelet therapy >3 months after implantation.

Serial long-term evaluation of neointimal stent coverage and thrombus after sirolimus-eluting stent implantation by use of coronary angioscopy

Objective: Progression of neointimal stent coverage (NSC) and changes in thrombus were evaluated serially by coronary angioscopy for up to 2 years after sirolimus-eluting stent (SES) implantation. Methods: Serial angioscopic observations were performed in 20 segments of 20 patients at baseline, at 6 months and at 2 years after SES implantation. NSC was classified as follows: 0, uncovered struts; 1, visible struts through thin neointima; or 2, no visible struts. In each patient, maximum and minimum NSC was evaluated. Existence of thrombus was also examined. Results: The maximum NSC increased from 6 months to 2 years (mean (SD) 1.2 (0.4) vs 1.8 (0.4), respectively, p = 0.005), while the minimum NSC did not change (0.7 (0.5) vs 0.8 (0.4), respectively, p = 0.25). The prevalence of patients with uncovered struts did not decrease from 6 months to 2 years (35% vs 20%, respectively, p = 0.29). Although there were no thrombus-related adverse events, new thrombus formation was found in 5% of 6-month, and in 20% of 2-year follow-up evaluations. The prevalence of thrombus inside the SES at baseline, 6 months and 2 years was similar (40%, 40% and 30%, respectively; p = NS). Conclusions: Neointimal growth inside the SES progressed heterogeneously. Uncovered struts persisted in 20% of the patients for up to 2 years and subclinical thrombus formation was not uncommon.

Chest Compression-Only Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest With Public-Access Defibrillation A Nationwide Cohort Study

Background—It remains unclear which is more effective to increase survival after out-of-hospital cardiac arrest in those with public-access defibrillation, bystander-initiated chest compression–only cardiopulmonary resuscitation (CPR) or conventional CPR with rescue breathing. Methods and Results—A nationwide, prospective, population-based observational study covering the whole population of Japan and involving consecutive out-of-hospital cardiac arrest patients with resuscitation attempts has been conducted since 2005. We enrolled all out-of-hospital cardiac arrests of presumed cardiac origin that were witnessed and received shocks with public-access automated external defibrillation (AEDs) by bystanders from January 1, 2005, to December 31, 2009. The main outcome measure was neurologically favorable 1-month survival. We compared outcomes by type of bystander-initiated CPR (chest compression–only CPR and conventional CPR with compressions and rescue breathing). Multivariable logistic regression was used to assess the relationship between the type of CPR and a better neurological outcome. During the 5 years, 1376 bystander-witnessed out-of-hospital cardiac arrests of cardiac origin in individuals who received CPR and shocks with public-access AEDs by bystanders were registered. Among them, 506 (36.8%) received chest compression–only CPR and 870 (63.2%) received conventional CPR. The chest compression–only CPR group (40.7%, 206 of 506) had a significantly higher rate of 1-month survival with favorable neurological outcome than the conventional CPR group (32.9%, 286 of 870; adjusted odds ratio, 1.33; 95% confidence interval, 1.03–1.70). Conclusions—Compression-only CPR is more effective than conventional CPR for patients in whom out-of-hospital cardiac arrest is witnessed and shocked with public-access defibrillation. Compression-only CPR is the most likely scenario in which lay rescuers can witness a sudden collapse and use public-access AEDs.

Adaptive Servo-Ventilation Therapy for Patients With Chronic Heart Failure in a Confirmatory, Multicenter, Randomized, Controlled Study

BACKGROUND Adaptive servo-ventilation (ASV) therapy is expected to be novel nonpharmacotherapy with hemodynamic effects on patients with chronic heart failure (CHF), but sufficient evidence has not been obtained. METHODS AND RESULTS A 24-week, open-label, randomized, controlled study was performed to confirm the cardiac function-improving effect of ASV therapy on CHF patients. At 39 institutions, 213 outpatients with CHF, whose left ventricular ejection fraction (LVEF) was <40% and who had mild to severe symptoms [New York Heart Association (NYHA) class: ≥II], were enrolled. After excluding 8 patients, 102 and 103 underwent ASV plus guideline-directed medical therapy (GDMT) [ASV group] and GDMT only [control group], respectively. The primary endpoint was LVEF, and the secondary endpoints were HF deterioration, B-type natriuretic peptide (BNP), and clinical composite response (CCR: NYHA class+HF deterioration). LVEF and BNP improved significantly at completion against the baseline values in the 2 groups. However, no significant difference was found between these groups. HF deterioration tended to be suppressed. The ASV group showed a significant improvement in CCR corroborated by significant improvements in NYHA class and ADL against the control group. CONCLUSIONS Under the present studys conditions, ASV therapy was not superior to GDMT in the cardiac function-improving effect but showed a clinical status-improving effect, thus indicating a given level of clinical benefit.