Evolution of a Large Language Model for Preoperative Assessment Based on the Japanese Circulation Society 2022 Guideline on Perioperative Cardiovascular Assessment and Management for Non-Cardiac Surgery.

Background: The Japanese Circulation Society 2022 Guideline on Perioperative Cardiovascular Assessment and Management for Non-Cardiac Surgery standardizes preoperative cardiovascular assessments. The present study investigated the efficacy of a large language model (LLM) in providing accurate responses meeting the JCS 2022 Guideline. Methods and Results: Data on consultation requests, physicians' cardiovascular records, and patients' response content were analyzed. Virtual scenarios were created using real-world clinical data, and a LLM was then consulted for such scenarios. Conclusions: Google BARD could accurately provide responses in accordance with the JCS 2022 Guideline in low-risk cases. Google Gemini has significantly improved its accuracy in intermediate- and high-risk cases.

Usefulness of scoring right ventricular function for assessment of prognostic factors in patients with chronic thromboembolic pulmonary hypertension.

Right ventricular (RV) function is associated with prognosis in chronic thromboembolic pulmonary hypertension (CTEPH). This study aimed to establish an RV dysfunction score using RV echocardiographic parameters to clarify the clinical characteristics in patients with CTEPH and to compare RV dysfunction score with parameters such as World Health Organization (WHO) functional class, hemodynamics, exercise capacity, and plasma BNP level. We enrolled 35 inpatients with CTEPH (mean age, 62 ± 15 years, 15 males). We constructed 'an RV dysfunction score' calculated as the summation of each point awarded for the presence of four parameters: tricuspid annular plane systolic excursion (TAPSE) < 16 mm, 1 point; tissue Doppler-derived tricuspid lateral annular systolic velocity (S') < 10 cm/s, 1 point; right ventricular fractional area change (RVFAC) < 35%, 1 point; and right ventricular myocardial performance index (RV-MPI) > 0.4, 1 point. TAPSE, S', RVFAC, and RV-MPI was 18.7 ± 4.8 mm, 11.9 ± 3.1 cm/s, 33.5 ± 13.9%, and 0.39 ± 0.2, respectively. The RV dysfunction score was associated with symptom [WHO functional class (p = 0.026)], hemodynamics [mean PAP (p = 0.01), cardiac index (p = 0.009), pulmonary vascular resistance (p = 0.001), and SvO2 (p = 0.039)], exercise capacity [6-min walk distance (p = 0.046), peakVO2 (p = 0.016), and VE/VCO2 slope (p = 0.031)], and plasma BNP level (p = 0.005). This RV dysfunction score using the four RV echocardiographic parameters could be a simple and useful scoring system to evaluate prognostic factors in patients with CTEPH.

Assessment of respiratory disturbance index determined with a non-restrictive monitor and of autonomic nervous system parameters in heart failure patients: A pilot study.

BACKGROUND: There is a link between sympathetic overactivity and sleep-disordered breathing (SDB), and both of which are important indicators of the development of heart failure. To manage the increasing numbers of heart failure patients, any method used to check for them needs to be as non-invasive, simple, and cost-effective as possible. The purpose of this study is to assess screening of SDB with a non-restrictive monitor and the autonomic nervous system in heart failure patients. METHODS: The subjects were 49 patients (mean age: 67 years; male: 78%) hospitalized for worsening heart failure. After stabilization with appropriate medical therapy, each patient simultaneously underwent sleep apnea syndrome (SAS) screening with the SD-101 (Kenzmedico Co. Ltd., Saitama, Japan), which is a novel, non-restrictive, sheet-like monitor for SAS screening, and assessment of heart rate variability (HRV) with a Holter monitor. In addition, we assessed daytime sleepiness by using the Epworth Sleepiness Scale. RESULTS: The mean respiratory disturbance index (RDI) was 21.9 events/h. Males had significantly greater RDI values than females (24.5±11.2 events/h vs. 13.0±6.2 events/h, p<0.001). RDI on SD-101 testing was closely correlated with cyclic variation of heart rate index obtained with a Holter electrocardiogram scanner (r=0.843). Although plasma brain natriuretic peptide level was not correlated with HRV, plasma norepinephrine level was moderately well correlated with the total low- to high-frequency ratio of HRV (r=0.529). CONCLUSIONS: SAS screening is important for heart failure patients, because absence of subjective sleepiness is not reliable in ruling out SDB. The SAS screening with SD-101 might apply for managing heart failure.

[Assessment of cardiac contractile reserve].

Left ventricular (LV) function is usually measured by imaging modalities such as echocardiography under static conditions in patients with dilated cardiomyopathy (DCM). However, some studies have reported that LV contractile function at rest is not reliable for assessment of the reversibility of LV contraction. Therefore, it is important to evaluate LV functional response under dynamic conditions by use of pharmacological as well as exercise stress (contractile reserve). In our studies, LVdP/dtmax was measured at rest and under dobutamine stress using a pigtail catheter with a high-fidelity micromanometer placed into the left ventricle in DCM patients. deltaVdP/dtmax as an index of myocardial contractile reserve was defined as the percentage increase in LVdP/dtmax induced by dobutamine infusion. Firstly, deltaLVdP/dtmax was correlated with peak oxygen consumption by cardiopulmonary exercise testing. In addition, impaired deltaLVdP/dtmax was associated with unfavorable prognosis. Secondly, reduced deltaLVdP/dtmax was associated with an increased washout rate evaluated by myocardial 123I-MIBG and 99mTc-MIBI scintigraphy. Finally, this residual contractile reserve was related to molecular remodeling caused by overactivation of the sympathetic nerve system in DCM patients. This review focused on the current status of contractile reserve with our findings, including procedures for evaluating contractile reserve, clinical implications, and molecular biological significance.

Association of cardiorespiratory fitness with characteristics of coronary plaque: assessment using integrated backscatter intravascular ultrasound and optical coherence tomography.

BACKGROUND: Cardiorespiratory fitness (CRF) can predict future cardiovascular disease. Rupture of vulnerable plaque which often has a large lipid core with a thin fibrous cap causes acute coronary syndrome including sudden cardiac death. We tested our hypothesis that preserved CRF is associated with low lipid composition and thick fibrous cap thickness of coronary lesions. METHODS: We prospectively performed both integrated backscatter intravascular ultrasound (IB-IVUS) and optical coherence tomography (OCT) for 77 non-culprit coronary lesions in 77 consecutive angina pectoris patients who underwent percutaneous coronary intervention (PCI). Percentage of achieved of predicted peak oxygen consumption (%PPeak Vo(2)) calculated based on measured peak Vo(2) using a cardiopulmonary exercise test performed post PCI was adapted as an indicator of patient CRF. RESULTS: Patients were divided into two groups [those with preserved CRF (%PPeak Vo(2) >82%) (Group I) or others (Group II)]. Coronary plaques of Group I patients had significantly smaller lipid volume, greater fibrous volume, and thicker fibrous cap thickness than those of Group II (32 ± 14% vs. 45 ± 13%, p<0.001; 57 ± 11% vs. 49 ± 11%, p<0.001; and 177.7 ± 20.9 µm vs. 143.7 ± 36.9 µm, p<0.001). In multivariate linear regression analysis, %PPeak Vo(2) showed a significantly negative correlation with lipid volume and a positive correlation with fibrous volume and fibrous cap thickness (ß=-0.418, p=0.001; ß=0.361, p=0.006; and ß=0.339, p=0.008). CONCLUSIONS: High %PPeak Vo(2) was associated with low lipid volume, high fibrous volume and thick fibrous cap thickness in coronary lesions. These results may well suggest an attenuated risk of cardiovascular events in patients with preserved CRF.