Validity of Diagnostic Algorithms for Cardiovascular Diseases in Japanese Health Insurance Claims.

BACKGROUND: We aimed to validate a claims-based diagnostic algorithm to identify hospitalized patients with acute major cardiovascular diseases (CVDs) from health insurance claims in Japan.Methods and Results: This retrospective multicenter validation study was conducted at 4 institutes, including Japanese Circulation Society-certified and uncertified hospitals in Japan. Data on patients with CVDs in departmental lists or with International Classification of Diseases, 10th Revision (ICD-10) codes for CVDs hospitalized between April 2018 and March 2019 were extracted. We examined the sensitivity and positive predictive value of a diagnostic algorithm using ICD-10 codes, medical examinations, and treatments for acute coronary syndrome (ACS), acute heart failure (HF), and acute aortic disease (AAD). We identified 409 patients with ACS (mean age 70.6 years; 24.7% female), 615 patients with acute HF (mean age 77.3 years; 46.2% female), and 122 patients with AAD (mean age 73.4 years; 36.1% female). The respective sensitivity and positive predictive value for the algorithm were 0.86 (95% confidence interval [CI] 0.82-0.89) and 0.95 (95% CI 0.92-0.97) for ACS; 0.74 (95% CI 0.70-0.77) and 0.79 (95% CI 0.76-0.83) for acute HF; and 0.86 (95% CI 0.79-0.92) and 0.83 (95% CI 0.76-0.89) for AAD. CONCLUSIONS: The validity of the diagnostic algorithm for Japanese claims data was acceptable. Our results serve as a foundation for future studies on CVDs using nationwide administrative data.

New Classification for the Combined Assessment of the Fractional Excretion of Urea Nitrogen and Estimated Plasma Volume Status in Acute Heart Failure.

Background The fractional excretion of urea nitrogen (FEUN) has been used as a renal blood flow index related to cardiac output, and the estimated plasma volume status (ePVS) as a body fluid volume index. However, the usefulness of their combination in acute decompensated heart failure (HF) management is unclear. We investigated the effect of 4 hemodynamic categories according to the high and low FEUN and ePVS values at discharge on the long-term prognosis of patients with acute decompensated HF. Methods and Results Between April 2011 and December 2018, we retrospectively identified 466 patients with acute decompensated HF with FEUN and ePVS values at discharge. Primary end point was postdischarge all-cause death. Secondary end points were (1) the composite of all-cause death and HF readmission, and (2) HF readmission in a time-to-event analysis. The patients were divided into 4 groups according to the high/low FEUN (≥35%, <35%) and ePVS (>5.5%, ≤5.5%) values at discharge: high-FEUN/low-ePVS, high-FEUN/high-ePVS, low-FEUN/low-ePVS, and low-FEUN/high-ePVS groups. During a median follow-up period of 28.1 months, there were 173 all-cause deaths (37.1%), 83 cardiovascular deaths (17.8%), and 121 HF readmissions (26.0%). The Kaplan-Meier curve analysis showed that the high-FEUN/low-ePVS group had a better prognosis than the other groups (log-rank test, P<0.001). In the multivariable Cox regression analysis, the low-FEUN/high-ePVS group had a higher mortality than the high-FEUN/low-ePVS group (hazard ratio, 2.92 [95% CIs, 1.73-4.92; P<0.001]). Conclusions The new classification of the 4 hemodynamic profiles using the FEUN and ePVS values may play an important role in improving outcomes in patients with stable acute decompensated HF.

Functional assessment of intermediate coronary artery stenosis with 4-Fr catheters.

The 4-Fr catheter system is not recommended for invasive functional assessment of coronary artery stenosis, because it tends to distort the aortic waveform. This study aimed to identify the incidence of aortic waveform distortion and a feasible method for correct diagnosis of coronary artery stenosis with a 4-Fr catheter. We retrospectively investigated 178 lesions with intermediate coronary artery stenosis. Non-hyperemic distal coronary artery pressure (Pd) and aortic pressure (Pa) were measured with a 4-Fr diagnostic or 6-Fr guiding catheter before and after saline flush. The mean Pd/mean Pa (Pd/Pa) and instantaneous wave-free ratio (iFR) were calculated before and after flushing. We compared the effect of flushing on the changes in Pd/Pa and iFR between the 4-Fr diagnostic and 6-Fr guiding catheters. Using the 4-Fr diagnostic catheter, there was a significant decrease in incidence of aortic waveform distortion from 42.0% (47 lesions) before flushing to 1.8% (2 lesions) after flushing (p < 0.001); the incidence was only 3.0% before saline flush and decreased to 0% after saline flush when using the 6-Fr guiding catheter. The presence of aortic waveform distortion influenced the iFR when the 4-Fr system was used. Functional measurements with the 4-Fr diagnostic catheter require adequate saline flush to remove the influence of aortic waveform distortion.

Primary Percutaneous Coronary Intervention in Elderly Patients With Acute Myocardial Infarction　- An Analysis From a Japanese Nationwide Claim-Based Database.

BACKGROUND: Primary percutaneous coronary intervention (pPCI) is strongly recommended by guidelines for patients presenting with acute myocardial infarction (AMI), but its applications in elderly patients are less clear.Methods and Results:The JROAD-DPC is a Japanese nationwide registry for patients with cardiovascular diseases combined with an administrative claim-based database. Among 2,369,165 records from 2012 to 2015, data for 115,407 AMI patients were extracted for this study. Elderly patients (≥75 years) comprised 45,645 subjects (39.6%), and received pPCI less frequently (62.2%) than younger patients (79.2%, P<0.001). Clinical variables such as higher age, female sex, higher Killip class, and renal dysfunction, but not functional status on admission, were predictors of non-application of pPCI. Endpoint 30-day mortality increased with aging, and was significantly higher in elderly patients (10.7%) than in younger patients (3.8%, P<0.001). Indeed, pPCI was independently associated with lower 30-day mortality only in subgroups of patients aged ≥60 years. Propensity score-matching analysis confirmed a similar reduction in endpoint 30-day mortality with pPCI in elderly patients. Duration of hospitalization was significantly shorter and functional ability on discharge was significantly better in elderly patients who underwent pPCI. CONCLUSIONS: Elderly patients with AMI underwent pPCI less frequently, but it was consistently associated with better clinical outcome in these patients. Our findings support the proactive application of pPCI for elderly AMI patients when they are eligible for an invasive strategy.

Hospitalization Costs for Patients With Acute Congestive Heart Failure in Japan.

BACKGROUND: With aging of the population, the economic burden associated with heart failure (HF) is expected to increase. However, little is known about the hospitalization costs associated with HF in Japan. Methods and Results: In this cross-sectional study, using data from The Japanese Registry of All Cardiac and Vascular Diseases (JROAD) and JROAD-Diagnosis Procedure Combination databases between 2012 and 2014, we evaluated hospitalization costs for acute cardiovascular diseases (CVDs), including HF. A total of $1,187 million/year (44% of the hospitalization costs for acute CVDs) was spent on patients with HF. We identified 273,865 patients with HF and the median cost per patient was $8,089 ($5,362-12,787) per episode. The top 1% of spenders accounted for 8% ($80 million/year), and the top 5% of spenders accounted for 22% ($229 million/year) of the entire cost associated with HF. The costs associated with HF for patients over 75 years of age accounted for 68% of the total cost. CONCLUSIONS: The costs associated with HF were higher than the hospitalization cost for any other acute CVD in Japan. Understanding how the total hospitalization cost is distributed may allow health providers to utilize limited resources more effectively for patients with HF.

The Current Status of Cardiovascular Medicine in Japan　- Analysis of a Large Number of Health Records From a Nationwide Claim-Based Database, JROAD-DPC.

BACKGROUND: Since cardiovascular disease accounts for one-quarter of deaths in the Japanese population, we developed a nationwide database using the administrative case-mix Diagnostic Procedure Combination (DPC) system (ie, theJapaneseRegistryOfAll cardiac and vascularDiseases (JROAD)-DPC) to reveal the current status of cardiovascular medicine in Japan.Methods and Results:The JROAD-DPC database included 704,593 health records' data of 2012 from 610 certificated hospitals of the Japanese Circulation Society. The 35,824 patients with acute myocardial infarction (AMI) and 108,665 patients with heart failure (HF) were admitted to hospitals. Increased hospital case volume was associated with reduced in-hospital mortality rates for both AMI and HF (P for trend <0.001). Although there was little variation among AMI patients in terms of aspirin use at discharge (median prescription rate, 83.0%; interquartile range [IQR], 76.9-88.0%), there were wide variations in the proportions of patients prescribed ß-blockers (BB) and angiotensin-converting enzyme inhibitors (ACEI)/angiotensin-receptor blockers (ARB) at discharge (BB, 41.4%, IQR 27.6-55.7%; ACEI/ARB, 52.0%, IQR 40.3-62.3%). In patients with HF, there were between-hospital variations in medications at discharge (BB, 38.1%, IQR, 27.8-47.6%; ACEI/ARB, 41.0%, IQR 31.7-49.1%). CONCLUSIONS: A nationwide administrative database of patients with cardiovascular diseases (JROAD-DPC) provided useful information that will contribute to improved quality of medical care, especially in the aging society of Japan, where HF has become an important health problem. (Circ J 2016; 80: 2327-2335).

Assessment of Coronary Plaque Vulnerability with Optical Coherence Tomography.

UNLABELLED: Several catheter-based imaging modalities have been developed over the past 2 decades for visualizing the morphological features of coronary atherosclerotic plaques that are susceptible to future development of serious cardiovascular events. Optical coherence tomography (OCT) is a new high-resolution intracoronary imaging modality based on near-infrared interferometry, and it has been shown to be able to identify various components of atheromatous plaques. In this review, we examine the histopathology of vulnerable plaques as a target for imaging technology, and discuss the evidence of OCT in identifying vulnerable atherosclerotic lesions in patients with coronary artery disease. KEY WORDS: Coronary artery disease; Optical coherence tomography; Vulnerable plaque.

OCT compared with IVUS in a coronary lesion assessment: the OPUS-CLASS study.

OBJECTIVES: The aim of this study was to investigate the reliability of frequency domain optical coherence tomography (FD-OCT) for coronary measurements compared with quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). BACKGROUND: Accurate luminal measurement is expected in FD-OCT because this technology offers high resolution and excellent contrast between lumen and vessel wall. METHODS: In 5 medical centers, 100 patients with coronary artery disease were prospectively studied by using angiography, FD-OCT, and IVUS. In addition, 5 phantom models of known lumen dimensions (lumen diameter 3.08 mm; lumen area 7.45 mm(2)) were examined using FD-OCT and IVUS. Quantitative image analyses of the coronary arteries and phantom models were performed by an independent core laboratory. RESULTS: In the clinical study, the mean minimum lumen diameter measured by QCA was significantly smaller than that measured by FD-OCT (1.81 ± 0.72 mm vs. 1.91 ± 0.69 mm; p < 0.001) and the minimum lumen diameter measured by IVUS was significantly greater than that measured by FD-OCT (2.09 ± 0.60 mm vs. 1.91 ± 0.69 mm; p < 0.001). The minimum lumen area measured by IVUS was significantly greater than that by FD-OCT (3.68 ± 2.06 mm(2) vs. 3.27 ± 2.22 mm(2); p < 0.001), although a significant correlation was observed between the 2 imaging techniques (r = 0.95, p < 0.001; mean difference 0.41 mm(2)). Both FD-OCT and IVUS exhibited good interobserver reproducibility, but the root-mean-squared deviation between measurements was approximately twice as high for the IVUS measurements compared with the FD-OCT measurements (0.32 mm(2) vs. 0.16 mm(2)). In a phantom model, the mean lumen area according to FD-OCT was equal to the actual lumen area of the phantom model, with low SD; IVUS overestimated the lumen area and was less reproducible than FD-OCT (8.03 ± 0.58 mm(2) vs. 7.45 ± 0.17 mm(2); p < 0.001). CONCLUSIONS: The results of this prospective multicenter study demonstrate that FD-OCT provides accurate and reproducible quantitative measurements of coronary dimensions in the clinical setting.

Morphological features of coronary arteries in patients with coronary spastic angina: assessment with intracoronary optical coherence tomography.

BACKGROUND: Coronary spasm (CS) plays an important role in the pathogenesis of many types of ischemic heart disease, but morphological appearance of non-stenotic coronary segments with CS is not fully understood. We evaluate the morphological characteristics of coronary arteries in patients with coronary spastic angina (CSA) using intravascular optical coherence tomography (OCT). METHODS: We evaluated 37 patients with resting chest pain whose coronary angiograms did not reveal significant stenosis. These patients underwent an acetylcholine (ACh) provocation test. OCT was performed after complete dilatation of coronary arteries, and additionally during ACh-induced CS in four patients. RESULTS: Based on the ACh test, 23 patients were diagnosed as having CSA, and the remaining 14 patients without CS were referred to as CS-negative. OCT study revealed that coronary segments with ACh-induced CS had homogeneous intimal thickening, and quantitative analysis showed that CS-positive segments had a significantly greater intima area as compared with corresponding CS-negative segments without lipid or calcium content. By contrast, CS-positive segments had a significantly smaller intima area as compared with CS-negative segments with lipid or calcium deposit. During ACh-induced CS, lumen and total vascular areas were significantly decreased, whereas intima area did not change in comparison with complete vasodilatation. The luminal surface of the intima formed a markedly wavy configuration during CS. CONCLUSIONS: Coronary artery segments involved in CS are characterized by diffuse intimal thickening without lipid or calcium content. High-resolution coronary OCT imaging could make it possible to analyze the vascular pathophysiology in patients with CS.

Novel application of black-blood echo-planar imaging to the assessment of myocardial infarction.

The purpose of this study was to clarify the characteristics of black-blood echo-planar imaging (BB-EPI) in the assessment of infarct-related myocardial edema (IRME), compared with T2-weighted imaging (T2WI). Thirteen acute myocardial infarction (MI) patients after reperfusion and 11 old MI patients underwent BB-EPI and T2WI, excluding those with posterior MI. In acute MI patients, signal intensity ratio (SI ratio) of edema to normal myocardium was measured. Black-blood echo-planar imaging revealed hyperintensity in the same region identified as IRME on T2WI in all acute MI patients, and SI ratio was significantly higher in BB-EPI (2.66 +/- 1.58) than in T2WI (1.44 +/- 0.22) (P < 0.05). However, BB-EPI showed hyperintensity in posterior wall, where there is no clinical evidence of acute MI, in 2 out of 13 acute MI patients. Both T2WI and BB-EPI detected no IRME in known old infarct area of all old MI patients, but BB-EPI showed hyperintensity in the posterior wall of 4 out of 11 old MI patients. Black-blood echo-planar imaging can depict IRME with sufficient suppression of background and blood flow signals, and with excellent edema-to-normal myocardium contrast resolution. However, BB-EPI sometimes shows an inconsistent signal area with T2WI specifically in posterior wall. The wide practical use of BB-EPI requires the solution to this serious problem.

Homeostasis model assessment of insulin resistance, quantitative insulin sensitivity check index, and oral glucose insulin sensitivity index in nonobese, nondiabetic subjects with high-normal blood pressure.

To investigate the relationships between high-normal blood pressure (BP) and insulin resistance, we examined insulin sensitivity in 306 nonobese and nondiabetic Japanese subjects with various BP categories (optimal BP, normal BP, high-normal BP, and hypertension). Insulin sensitivity was measured from fasting plasma glucose and insulin values and those during a 75-g oral glucose tolerance test by five formulas: the homeostasis model assessment of insulin resistance (HOMA-R), the quantitative insulin sensitivity check index (QUICKI), the oral glucose insulin sensitivity (OGIS) index, and two insulin sensitivity indexes (ISI-composite and ISI-stumvoll). The HOMA-R was significantly higher, and the QUICKI was significantly lower in subjects with hypertension than in subjects with optimal BP. Both HOMA-R and QUICKI values showed that high-normal BP patients had a higher (but not significant) degree of insulin resistance than optimal BP patients. The OGIS index was significantly lower in subjects with high-normal BP or hypertension than in subjects with optimal BP. The ISI-composite was significantly lower in subjects with high-normal BP or hypertension than in subjects with optimal BP, and it was also significantly lower in subjects with hypertension than in subjects with normal BP. The ISI-stumvoll was significantly lower in subjects with high-normal BP or hypertension than in subjects with optimal BP. The OGIS index, ISI-composite, and ISI-stumvoll significantly decreased with increasing severity of BP status among the normotensive groups (optimal BP, normal BP, and high-normal BP). These findings indicate that insulin resistance is present even in the high-normal BP categories of nonobese and nondiabetic Japanese individuals.

[Assessment of coronary artery by four-detector multislice computed tomography: diagnostic accuracy and limitations for coronary artery lesions].

OBJECTIVES: The applicability of four-detector multislice computed tomography (MSCT) was investigated for evaluating coronary arteries. METHODS: MSCT (Somatom Volume Zoom, Siemens) was used to evaluate the coronary arteries in 94 patients. The reconstructed images were analyzed using retrospective electrocardiographic gating to determine the image quality of the coronary arteries. In addition, the ability of MSCT to detect coronary artery lesions of > or = 70% (> or = 50% in the left main trunk) diameter stenoses documented by standard coronary angiography was assessed in 67 patients who underwent coronary angiography within the same period. RESULTS: Good image quality was displayed in 488 (58%) and fair in 184 (22%) of a total of 846 coronary segments, but non-assessable in 174 (21%) due to degraded image quality. MDCT detected 33 stenotic lesions correctly in 494 assessable segments, comparable to coronary angiography. The sensitivity and specificity of MSCT were 0.79 and 0.95, respectively. However, an additional 15 lesions were detected by coronary angiography among the non-assessable segments. In total, 24 lesions were missed by MSCT. Accordingly, coronary segments were completely assessable and correctly detected by MSCT in only 20 patients (30%), or 35 (52%) if the distal coronary segments were excluded from analysis. CONCLUSIONS: Four-detector MSCT for detection of coronary artery lesions was applicable to assessable segments. However, clinical use may presently be limited because of the insufficient overall accuracy. Further technical improvement is expected in the near future.