Ambient Temperature and Cardiorenal Connection in Elderly Patients with Stable Heart Failure.

Heart failure increases among the elderly; however, the influence of ambient temperature on cardiorenal function has not been well investigated. Patients (n = 110, mean age 82.9 years, 43 males) with stable heart failure and creatinine < 3.0 mg/dl were studied. Medical records, such as ejection fraction, B-type natriuretic peptide (BNP), and estimated glomerular filtration rate (eGFR) at each visit every 1-3 months were collected by the end-point for death, additional prescription to treat heart failure, or heart failure hospitalization. The ambient temperatures at each visit were obtained from the Japan Meteorological Agency. During the follow-up period (median 399 days and 7 visits), follow-up BNP showed a trend toward a positive correlation with the diurnal temperature range. After dividing into two groups by median baseline eGFR, follow-up BNP was positively correlated with minimum temperature (p = 0.039) and the diurnal temperature range (p = 0.007) in the Low-eGFR group but not in the High-eGFR group. Follow-up eGFR was negatively correlated with the ambient day temperature in both groups (p ≤ 0.002). Follow-up BNP was positively correlated with follow-up eGFR (p < 0.0001) only in the Low-eGFR group and not in the High-eGFR group, suggesting that BNP and eGFR increase in winter and BNP and eGFR decrease in summer in the Low-eGFR group. In conclusions, heart failure may be worsened by larger diurnal temperature range or in winter in patients with renal impairment. This population should be carefully managed in the clinic according to the ambient temperature.

Malondialdehyde-modified low-density lipoprotein is a useful marker to identify patients with vulnerable plaque.

BACKGROUND: The association between elevated malondialdehyde-modified low-density lipoprotein (MDA-LDL) and plaque instability in patients with coronary artery disease (CAD) is suspected but not established. The aim of the present study was therefore to investigate the association between serum MDA-LDL and plaque characteristics on angioscopy. METHODS AND RESULTS: A total of 37 consecutive patients with CAD and single-vessel disease who underwent pre-interventional angioscopy, were studied. Using angioscopy at the target lesions, the presence of yellow plaque and complex plaque was examined. Moreover, we evaluated the yellow intensity, which has been shown to have an inverse correlation with the fibrous-cap thickness of the plaques, with quantitative colorimetry to identify a thin-cap atheroma. Serum MDA-LDL in patients with thin-cap atheroma diagnosed on quantitative colorimetry was significantly higher than in patients without thin-cap atheroma (P<0.0009). Univariate logistic regression indicated that serum MDA-LDL was a predictor for thin-cap atheroma (odds ratio [OR], 1.48; 95% confidence interval [CI]: 1.10-1.97; P=0.003) and for complex plaque (OR, 1.22; 95% CI: 1.00-1.48; P=0.046). On multivariate logistic regression serum MDA-LDL was the only independent predictor for thin-cap atheroma (OR, 1.48; 95% CI: 1.10-1.97; P=0.011). CONCLUSIONS: Using angioscopy and quantitative colorimetry, elevated MDA-LDL was confirmed to be associated with thin-cap atheroma in CAD patients.

Disruption of atherosclerotic neointima seven years after bare metal stent deployment.

A 58-year-old male with a history of prior myocardial infarction, hypertension, and dyslipidemia was admitted due to deteriorating exertional angina. A bare metal stent (Multilink plus™, GUIDANT Corporation, Santa Clara, CA, USA) had been implanted into the proximal left anterior descending artery because of ST-elevation myocardial infarction 7 years earlier. Optical coherence tomography (OCT) showed a disruption of the atherosclerotic neointima overlying the stent. Intravascular imaging studies and pathological studies have shown that neointima within a bare-metal stent often transform into atherosclerotic tissue during an extended period of time. In the current report, OCT demonstrated that a disruption of the atherosclerotic neointima has the potential to cause the development of unstable clinical features. OCT examinations therefore help to understand the pathogenesis of acute coronary syndrome after stent implantation.

Successful Leadless Pacemaker Implantation in an Elderly Patient With Dextrocardia and Situs Inversus.

Leadless pacemaker is indicated in patients with symptomatic bradycardia as an alternative therapy when transvenous pacemaker implantation is considered difficult or at high risk. The experience of implanting leadless pacemaker in patients with dextrocardia and situs inversus is limited. A 94-year-old male was transferred to our hospital due to advanced atrio-ventricular block with episode of syncope. Chest radiograph and computed tomography revealed dextrocardia with situs inversus. Emergency cardiac catheterization was performed and a temporary pacemaker was inserted, but the patient removed it due to delirium. So, a leadless pacemaker was implanted to him. Shorter time of bed-rest after the implantation and shorter hospital stay would be beneficial of implanting a leadless pacemaker. Precise anatomical evaluation would be important to perform implantation efficiently and safely.

Angioscopic study of silent plaque disruption in nonischemic related coronary artery in patients with stable ischemic heart disease.

Plaque disruption, which may be associated with some coronary risk factors, plays a key role in the development of acute coronary syndromes and progression of atherosclerosis. However, the clinical profile of asymptomatic plaque disruption in stable ischemic heart disease has not been well evaluated. The aim of the present study was to investigate the frequency and determinants of silent plaque disruption (SPD) in patients with stable ischemic heart disease using coronary angioscopy. Forty-one patients with stable angina or old myocardial infarction (OMI) without any complaints within 3 months were included in the present study. Angioscopy was successfully performed through 49 nonischemic related coronary arteries. The presence of SPD and coronary risk factors were recorded. Silent plaque disruption was found in 12 patients with stable ischemic heart disease (12/41, 29.3%), and the frequency of SPD in nonischemic related coronary arteries was 26.5% (13/49). A significantly higher frequency of SPD was noted in yellow plaques than in white plaques (35.3% versus 6.7%, P = 0.043). Overall, the independent clinical risk factors of SPD in nonischemic related coronary arteries were diabetes mellitus (P = 0.018; OR, 18.8209; 95% CI, 1.6525 to 214.3523) and hypertension (P = 0.0313; OR, 6.6485; 95% CI, 1.1850 to 37.3019). These results suggest silent plaque disruption was commonly observed in nonischemic related coronary arteries in patients with stable ischemic heart disease and its determinants were diabetes mellitus and hypertension.

Relationship between neointimal coverage of sirolimus-eluting stents and lesion characteristics: a study with serial coronary angioscopy.

BACKGROUND: Delayed neointimal coverage after the implantation of a drug-eluting stent (DES) is thought to be related to their potential for developing late-stent thrombosis. However, few studies have shown which factor affects the neointimal coverage after DES implantation. We hypothesized that the extent of neointimal coverage after DES implantation is affected by the underlying lesion characteristics because arterial wall components are reported to determine the transport and distribution of the drugs. METHODS: Thirty-seven coronary artery lesions treated with a single sirolimus-eluting stent (SES) were evaluated in 37 patients with stable coronary artery disease. Angioscopy was performed before, immediately after, and 6 months after stenting to examine the existence of yellow plaque, thrombus, complex plaque, and intramural hemorrhage and the degree of neointimal coverage at 6-month follow-up. This was classified either as a noncoverage group (stent struts were predominantly exposed or visible through a thin neointima) or as a coverage group (stent struts were predominantly covered by neointimal hyperplasia and thus invisible). RESULTS: Twenty-one lesions were classified into the noncoverage group, and 16 lesions the coverage group. The frequency of preexistent yellow plaques was significantly higher in the noncoverage group than that in the coverage group (67% vs 19%, P = .007). A multivariate logistic regression analysis showed the preexistence of yellow plaque was the only independent factor behind less neointimal coverage at 6 months after SES implantation (odds ratio 19.5, 95% confidence interval 1.58-240.50, P = .020). CONCLUSIONS: The preexistence of yellow plaque may be associated with decreased neointimal coverage of SES.

Advanced neointimal growth is not associated with a low risk of in-stent thrombus. Optical coherence tomographic findings after first-generation drug-eluting stent implantation.

BACKGROUND: There is a hypothesis that advanced neointimal stent coverage may protect against stent thrombosis. In the present study, differences in neointimal growth and prevalence of in-stent thrombus between paclitaxel- and sirolimus-eluting stent (PES and SES) were evaluated by optical coherence tomography (OCT). METHODS AND RESULTS: Follow-up angiographic and OCT examinations at approximately 6 months were performed for 40 patients (20 PES, 20 SES). Late loss was measured by quantitative coronary angiography. Neointimal hyperplasia (NIH) thickness on stent struts was measured by cross-sectional OCT images at 1 mm intervals. After measuring the NIH area in each cross-section, NIH volume was calculated as integral of NIH area within the stent. Late loss, NIH thickness, and NIH volume were greater for PES than for SES (0.42 +/-0.44 vs 0.13 +/-0.12 mm, 118 +/-141 vs 31 +/-39 mum, 53.2 +/-30.5 vs 24.3 +/-14.0 mm(3); P<0.05, respectively). In-stent thrombus was found more frequently in PES than in SES (50 vs 15%; P=0.02). CONCLUSIONS: Although the degree of neointimal growth in PES was generally greater, in-stent thrombus was more common compared with SES. Presence of thrombus in first-generation drug-eluting stents was not related to advanced neointimal growth.

In vivo comparison of optical coherence tomography and angioscopy for the evaluation of coronary plaque characteristics.

Atherosclerotic yellow plaques identified by coronary angioscopy are considered as vulnerable plaques. However, characteristics of yellow plaques are not well understood. Optical coherence tomography (OCT) provides accurate tissue characterization in vivo and has the capability to measure fibrous cap thickness covering a lipid plaque. Characteristics of yellow plaques identified by angioscopy were evaluated by OCT. We examined 205 plaques of 41 coronary arteries in 26 patients. In OCT analysis, plaques were classified as fibrous or lipid. Minimal lumen area of the plaque, arch of the lipid, and fibrous cap thickness on the lipid plaque were measured. Yellow grade of the plaque was defined as 0 (white), 1 (light yellow), 2 (medium yellow), or 3 (dark yellow) based on the angioscopy. A total of 149 plaques were diagnosed as lipid plaques. Neither the minimal lumen area nor the arch of the lipid was related to the yellow grade. There was an inverse relationship between color grade and the fibrous cap thickness (grade 0 [n = 45] 218 +/- 89 microm, grade 1 [n = 40] 101 +/- 8 microm, grade 2 [n = 46] 72 +/- 10 microm, and grade 3 [n = 18] 40 +/- 14 microm; p <0.05). Sensitivity and specificity of the angioscopy-identified yellow plaque for having a thin fibrous cap (thickness

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.

Evaluation by optical coherence tomography of neointimal coverage of sirolimus-eluting stent three months after implantation.

Confirming complete neointimal coverage after implantation of a drug-eluting stent is clinically important because incomplete stent coverage is responsible for late thrombosis and sudden cardiac death. Optical coherence tomography is a high-resolution (approximately 10 microm) imaging technique capable of detecting a thin layer of neointimal hyperplasia (NIH) inside a sirolimus-eluting stent (SES) and stent malapposition. This investigation evaluated stent exposure and malapposition 3 months after SES implantation using optical coherence tomography in a different clinical presentations, such as acute coronary syndrome (ACS) and non-ACS. Motorized optical coherence tomographic pullback (1 mm/s) was performed at 3-month follow-up to examine consecutive implanted 31 SESs in 21 lesions in 21 patients (9 with ACS and 12 with non-ACS). NIH thickness inside each strut and percent NIH area in each cross section were measured. In total, 4,516 struts in 567-mm single-stented segments were analyzed. Overall, NIH thickness and percent NIH area were 29 +/- 41 microm and 10 +/- 4%, respectively. Rates of exposed struts and exposed struts with malapposition were 15% and 6%, respectively. These were more frequent in patients with ACS than in those with non-ACS (18% vs 13%, p <0.0001; 8% vs 5%, p <0.005, respectively). In conclusion, neointimal coverage over a SES at 3-month follow-up is incomplete in ACS and non-ACS. Our study suggests that dual antiplatelet therapy might be continued >3 months after SES implantation.

Angioscopic follow-up study of coronary ruptured plaques in nonculprit lesions.

OBJECTIVES: Changes of ruptured plaques in nonculprit lesions were evaluated using coronary angioscopy. BACKGROUND: The concept of multiple coronary plaque ruptures has been established. However, no detailed follow-up studies of ruptured plaques in nonculprit lesions have yet been reported. METHODS: Forty-eight thrombi in 50 ruptured coronary plaques in nonculprit lesions in 30 patients were identified by angioscopy. The percent diameter stenosis (%DS) at the target plaques on quantitative coronary angiographic analysis and the serum C-reactive protein (CRP) level were measured. RESULTS: The mean angioscopic follow-up period was 13 +/- 9 months. Thirty-five superimposed thrombi still remained at follow-up, and the predominant thrombus color changed from red (56%) at baseline to pinkish-white (83%) at follow-up. The healing rate increased according to the angioscopic follow-up period (23% at 12 months, p = 0.044). The %DS at the healed plaque increased from baseline to follow-up (12.3 +/- 5.8% vs. 22.7 +/- 11.6%, respectively; p = 0.0004). The serum CRP level in patients with healed plaques (n = 10) was lower than that in those without healed plaques (n = 19; 0.07 +/- 0.03 mg/dl vs. 0.15 +/- 0.11 mg/dl, respectively; p = 0.007). CONCLUSIONS: The present study demonstrated that: 1) ruptured plaques in nonculprit lesions tend to heal slowly with a progression of angiographic stenosis; and 2) the serum CRP level might reflect the disease activity of the plaque ruptures.

Significance of plaque disruption sites in acute coronary syndrome.

Coronary plaque disruption and subsequent thrombosis occur in both unstable angina (UA) and acute myocardial infarction (AMI). However, it is unclear why UA and AMI have different clinical courses. The purpose of this angiographic study was to examine whether the longitudinal plaque disruption site is a factor that can be used to distinguish these two conditions. Seventy-two patients with AMI or UA in whom ischemia- or infarct-related arteries and plaque disruption sites could be determined were enrolled. The plaque disruption sites were classified as upstream type or downstream type. The upstream type and downstream type were defined as plaque rupture site located proximal and distal, respectively, to the maximum stenosis on angiography. The frequency of the upstream type was significantly higher in patients with AMI (60.0%) than in patients with UA (18.5%). On the other hand, the frequency of the downstream type was higher in patients with UA (81.5%) in patients with AMI (40.0%; p<0.01). The longitudinal plaque disruption site may thus be a factor that can be used to distinguish these two diseases.

Extreme late-phase observation using coronary angioscopy until 7 years after sirolimus-eluting stent implantation.

BACKGROUND: Little is known about the very late-phase morphological vessel characteristics within the sirolimus-eluting stent (SES). METHODS AND RESULTS: We assessed a total of 12 patients with 15 SES implantations who underwent repeat angiographic and angioscopic procedures after 5 and 7 years. The degree of neointimal stent coverage (NSC) was classified as follows: grade 0, uncovered struts; grade 1, visible struts through a thin neointima; or grade 2, invisible struts with complete neointimal coverage. The maximum and minimum NSC grades were evaluated and the existence of in-stent thrombus was also recorded for all patients. The prevalence of a maximum NSC grade of 2 increased and that of a minimum NSC grade of 0 decreased, although there was no significant difference in prevalence between 5 and 7 years. One of four in-stent thrombus identified at 5 years had disappeared from 5 to 7 years and a new thrombus was found in another patient at 7 years. Thus, the incidence of in-stent thrombus did not change from 5 to 7 years. In one case, a thrombus was observed inside the angiographic aneurysmal change, but none of the thrombi were related to adverse events. CONCLUSION: This angioscopic study reported gradual arterial repair and continuous delayed healing associated with subclinical thrombus formation 7 years after SES deployment.

Coronary atherosclerosis and risk of acute coronary syndromes in chronic kidney disease using angioscopy and the kidney disease: Improving Global Outcomes (KDIGO) classification.

OBJECTIVE: This 8-year follow-up cohort study evaluated and compared the degree of coronary atherosclerosis in chronic kidney disease (CKD) according to the Kidney Disease: Improving Global Outcomes (KDIGO) classification using multivessel angioscopy and investigated the impact of the vulnerability of coronary arteries on the relationship between the classification and risk of acute coronary syndromes (ACS). METHODS: We studied 89 coronary artery disease patients who underwent angioscopic observation of multiple coronary arteries. The patients were divided into 3 groups: Risk 0, 1, and 2 were equivalent to low risk, moderately high risk, and high and severely high risk, respectively. We examined the frequencies of complex and yellow plaques. Furthermore, we followed all patients for de novo ACS, dividing into two groups according to the existence of vulnerable coronary atherosclerosis (VCA) based on angioscopic findings. RESULTS: The number of yellow plaques per vessel, maximum yellow grade, number of complex plaques per vessel, and cumulative incidence of ACS in all patients were significantly associated with Risk grade progression (p < 0.05 for trend). Among the patients with VCA, Risk 2 had a higher incidence of ACS than Risk0 (p < 0.014) and Risk 1 (p < 0.007), whereas Risk 0 and Risk 1 had similar outcomes. Among the patients without VCA, no de novo ACS events were seen regardless of the Risk group. CONCLUSIONS: Coronary atherosclerosis progressed in the early stages of CKD, and once it reached to a vulnerable stage, advanced CKD patients had a synergistically increased risk of ACS.

Relationship between cholesterol crystals and culprit lesion characteristics in patients with stable coronary artery disease: an optical coherence tomography study.

AIMS: Some recent studies have reported the role of cholesterol crystals (ChCs) in plaque rupture in patients with coronary artery disease. We used optical coherence tomography (OCT) to investigate the characteristics of coronary plaques that were associated with derived ChCs. METHODS: We evaluated 101 subjects with stable coronary artery disease who underwent OCT. We compared the OCT findings of the culprit lesions with ChCs to those without ChCs and investigated the background characteristics. RESULTS: ChCs were observed in culprit lesions of 39 patients. The frequencies of spotty calcification, microchannel structure, and lipid-rich plaque were significantly higher in patients with ChCs than those without ChCs (64.1 vs. 27.4%, p < 0.001; 69.2 vs. 38.7%, p = 0.003; 53.8 vs. 29.0%, p = 0.01, respectively). On the other hand, the frequencies of thrombus, disruption, and thin-cap fibroatheroma did not differ significantly between patients with and without ChCs (15.3 vs. 24.1%, p = 0.3; 33.3 vs. 17.7%, p = 0.07; and 33.3 vs. 24.1 %, p = 0.3, respectively). Among the possible clinical factors, multivariate analysis showed an elevated level of glycated hemoglobin as the sole significant factor associated with ChCs. CONCLUSION: ChCs are frequently associated with the major findings of vulnerable plaque, and are often seen in poorly controlled diabetic patients. Thus, ChCs might be one of the features of vulnerable plaque.

Usefulness of rosuvastatin to prevent periprocedural myocardial injury in patients undergoing elective coronary intervention.

The aim of the present study was to investigate whether percutaneous coronary intervention-related periprocedural myocardial infarction (MI) can be suppressed more significantly with high- compared with low-dose rosuvastatin. A total of 232 patients scheduled to undergo elective percutaneous coronary intervention within 5 to 7 days were assigned to groups that would receive either 2.5 or 20 mg/day of rosuvastatin (n = 116 each). The incidence of periprocedural MI did not significantly differ between the high and low-dose groups (8.7% vs 18.7%, p = 0.052). In patients who were not taking statins at the time of enrollment, high-dose rosuvastatin significantly suppressed periprocedural MI compared with the low dose (10.5% vs 30.0%, p = 0.037). The difference was not significant in patients who were already taking statins (high vs low dose 7.6% vs 10.6%, p = 0.582). In conclusion, the incidence of percutaneous coronary intervention-related periprocedural MI was reduced more effectively by high-dose than by low-dose rosuvastatin in statin-naive patients. However, low-dose rosuvastatin is sufficient for patients who are already taking statins.

Impact of prediabetic status on coronary atherosclerosis: a multivessel angioscopic study.

OBJECTIVE: To determine if prediabetes is associated with atherosclerosis of coronary arteries, we evaluated the degree of coronary atherosclerosis in nondiabetic, prediabetic, and diabetic patients by using coronary angioscopy to identify plaque vulnerability based on yellow color intensity. RESEARCH DESIGN AND METHODS: Sixty-seven patients with coronary artery disease (CAD) underwent angioscopic observation of multiple main-trunk coronary arteries. According to the American Diabetes Association guidelines, patients were divided into nondiabetic (n = 16), prediabetic (n = 28), and diabetic (n = 23) groups. Plaque color grade was defined as 1 (light yellow), 2 (yellow), or 3 (intense yellow) based on angioscopic findings. The number of yellow plaques (NYPs) per vessel and maximum yellow grade (MYG) were compared among the groups. RESULTS: Mean NYP and MYG differed significantly between the groups (P = 0.01 and P = 0.047, respectively). These indexes were higher in prediabetic than in nondiabetic patients (P = 0.02 and P = 0.04, respectively), but similar in prediabetic and diabetic patients (P = 0.44 and P = 0.21, respectively). Diabetes and prediabetes were independent predictors of multiple yellow plaques (NYPs ≥2) in multivariate logistic regression analysis (odds ratio [OR] 10.8 [95% CI 2.09-55.6], P = 0.005; and OR 4.13 [95% CI 1.01-17.0], P = 0.049, respectively). CONCLUSIONS: Coronary atherosclerosis and plaque vulnerability were more advanced in prediabetic than in nondiabetic patients and comparable between prediabetic and diabetic patients. Slight or mild disorders in glucose metabolism, such as prediabetes, could be a risk factor for CAD, as is diabetes itself.

Current status of optical coherence tomography.

Optical coherence tomography (OCT) is a novel imaging technology based on low-coherence interferometry that use near-infrared light in real-time, and allows cross-sectional in-situ visualization of the vessel wall at the microscopic level. OCT provides 10-fold higher resolution than intravascular ultrasound which is currently the most used modality for intra-coronary imaging. OCT offers the obvious advantages when characterizing precise plaque microstructure and distinguishing various type of plaques. OCT is also being assessed for its potential role in the understanding of neointimal coverage, vascular healing and the progression of atherosclerosis in coronary vasculature after stenting on the micron scale. These unique capabilities could be helpful in guiding coronary management and interventions. Recent improvement in next generation OCT technology, such as frequency-domain OCT, will allow for a simple imaging procedure, providing more useful information and complementing other modalities on both clinical and research applications for the cardiologists.