神野 真司

OBJECTIVES: This study aimed to measure right atrial (RA) strain in the reservoir, conduit, and contraction phases and examine its clinical utility in detecting pulmonary hypertension (PH). METHODS: One hundred and thirteen patients hospitalized in the intensive or coronary care units of our institution who underwent echocardiography and measurements of RA/right ventricular (RV) strain were retrospectively examined. RA strain was measured in the reservoir, conduit, and contraction phases of one cardiac cycle. PH was defined as peak tricuspid regurgitation velocity >2.8 m/s. Patients were grouped according to PH status (PH, no PH) and statistically compared. Logistic regression and receiver operating characteristic analyses were also performed. RESULTS: Mean age was 71.1±15.4 years and 72 were men (63.7%). The PH and no PH groups comprised 40 and 73 patients, respectively. Among the RA strain parameters, RA strain in the conduit phase was significantly lower in the PH group (-8.1±4.2% vs. -17.4±7.7%; p<0.001). In the receiver operating characteristic analysis for PH, RA strain in the conduit phase had the highest area under the curve among the RA/RV strain parameters (area under the curve, 0.88; sensitivity, 92.5%; specificity, 71.2%; p<0.001). CONCLUSIONS: RA strain is an echocardiographic parameter that can detect PH and should be considered when RV strain parameters are not measurable.

INTRODUCTION: Coronary computed tomography angiography (CCTA) is known to have a high negative predictive value (NPV) in identifying coronary artery disease (CAD). This study aimed to examine whether resting echocardiographic parameters could exclude significant CAD on CCTA. METHODS: We recruited 142 patients who had undergone both CCTA and echocardiography within a 3-month window. Based on the CCTA findings, patients were divided into two groups: Group A (non-significant CAD, defined as all coronary segments having <50% stenosis) and Group B (significant CAD). Resting echocardiographic parameters were compared between the two groups to identify predictors of non-significant CAD on CCTA. RESULTS: A total 92 patients (mean age, 68 ± 13 years; males, 62%) were eligible for this study; 50 in Group A and 42 in Group B. Among the various echo parameters, left atrial volume index (LAVI) and left ventricular (LV) global longitudinal strain (GLS) were significantly lower in Group A (23.5 ± 7.6 vs. 33.6 ± 7.4 mL/m2 , p < .001; -20.2 ± 1.8% vs. -16.8 ± 2.0%, p < .001, respectively). Analysis of the receiver operating characteristic curve revealed that the cutoff value to exclude significant CAD on CCTA was 29.0 mL/m2 for LAVI (NPV 80.8%) and -18.1% for GLS (NPV 80.7%). The NPV increased to 95.0% when these parameters were combined (LAVI < 29.0 mL/m2 and GLS < -18.1%). CONCLUSION: The combination of resting LAVI and GLS was clinically useful in excluding significant CAD via CCTA.

OBJECTIVES: We aimed to identify which resting echocardiographic parameters can detect asymptomatic or mildly symptomatic patients with primary mitral regurgitation (MR) who require exercise stress echocardiography (ESE) to determine their suitability for surgery. METHODS: We examined 56 consecutive patients with primary moderate/severe MR who underwent ergometer-based ESE. Patients who met the surgical indications at rest were excluded. Eligible patients were divided into Group I (pulmonary artery systolic pressure [PASP] during exercise >60 mmHg; n=11) and Group II (PASP during exercise ≤60 mmHg; n=30). RESULTS: Forty-one patients were included. Group I was significantly older (65±12 vs. 54±14 years, P=0.042) and had significantly higher serum N-terminal pro-B-type natriuretic peptide concentrations than Group II (351±278 vs. 125±163 pg/mL, P=0.002). The univariate analysis demonstrated that peak E wave velocity (Group I vs. Group II: 125±45 vs. 101±24 cm/sec, P=0.050), left ventricular (LV) end-diastolic diameter index (32±4 vs. 30±3 mm/m2, P=0.035), and left atrial volume index (LAVI; 45±14 vs. 30±11 mL/m2, P=0.008) were predictors of increased PASP during exercise. In the multivariate analysis, resting LAVI best predicted exercise-induced pulmonary hypertension (hazard ratio 1.081 [95% confidence interval 1.009-1.158], P=0.028), with a cutoff value of 37 mL/m2. CONCLUSIONS: In asymptomatic or mildly symptomatic patients with primary moderate/severe MR, increased resting LAVI indicates the requirement for ESE, even without LV dilatation.

当院では，循環器内科医師と臨床検査技師で構成される心エコーチームによる，スキルアップを目的とした心エコーカンファレンスを毎週開催している。しかし，2020年4月よりCOVID-19感染対策の観点から開催の自粛を余儀なくされている。そこで我々は，インフォメーションテクノロジー（information technology; IT）を用いた，ワールド・ワイド・ウェブ（World Wide Web; Web）上での関連病院合同教育プログラムを代替実施し，今回その有用性を検証した。心エコーチーム計23人（当院19人，関連病院4人）を対象に，オンラインサービスを用いて症例問題を作成し，解答を募った。従来の心エコーカンファレンスの参加者は平均8.2人であったが，Webによる開催は参加可能な対象者が拡大し平均13.7人と増加した。正答者率の数値化により，各疾患に対する理解度を明らかにすることができた。最も正答者率が低かった問題に関しては，教育プログラムを提示することで正答者率の有意な改善が認められた。また，フリーコメントの記載により問題点が明確になり，的確な改善策が講じられたことも利点であった。Webを用いた教育環境は，時間や場所を選ばずに自由な参加形式を取れることから，多くの利点がある。さらに，本教育プログラムは症例問題を案出することにより地域医療施設間の精度管理に応用でき，大学と連携することで医学教育にも貢献できる可能性が示唆された。