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Objectives: In hypertrophic cardiomyopathy (HCM), specific ECG abnormalities are observed. Therefore, ECG is a valuable screening tool. Although several studies have reported on estimating the risk of developing fatal arrhythmias from ECG findings, the use of ECG to identify the severity of heart failure (HF) by applying deep learning (DL) methods has not been established., Methods: We assessed whether data-driven machine-learning methods could effectively identify the severity of HF in patients with HCM. A residual neural network-based model was developed using 12-lead ECG data from 218 patients with HCM and 245 patients with non-HCM, categorised them into two (mild-to-moderate and severe) or three (mild, moderate and severe) severities of HF. These severities were defined according to the New York Heart Association functional class and levels of the N-terminal prohormone of brain natriuretic peptide. In addition, the patients were divided into groups according to Kansas City Cardiomyopathy Questionnaire (KCCQ)-12. A transfer learning method was applied to resolve the issue of the low number of target samples. The model was trained in advance using PTB-XL, which is an open ECG dataset., Results: The model trained with our dataset achieved a weighted average F1 score of 0.745 and precision of 0.750 for the mild-to-moderate class samples. Similar results were obtained for grouping based on KCCQ-12. Through data analyses using the Guided Gradient Weighted-Class Activation Map and Integrated Gradients, QRS waves were intensively highlighted among true-positive mild-to-moderate class cases, while the highlighted part was highly variable among true-positive severe class cases., Conclusions: We developed a model for classifying HF severity in patients with HCM using a deep neural network algorithm with 12-lead ECG data. Our findings suggest that applications of this DL algorithm for using 12-lead ECG data may be useful to classify the HF status in patients with HCM., Competing Interests: Competing interests: YM reports receipt of scholarship funds or donations scholarship funds from Abbott Medical Japan and BIOTRONIK JAPAN. The other authors declare no conflicts of interest., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective The cardiac function, blood distribution, and oxygen extraction in the muscles as well as the pulmonary function determine the oxygen uptake (VO 2 ) kinetics at the onset of exercise. This factor is called the VO 2 time constant, and its prolongation is associated with an unfavorable prognosis for heart failure (HF). The mitochondrial function of skeletal muscle is known to reflect exercise tolerance. Morphological changes and dysfunction in cardiac mitochondria are closely related to HF severity and its prognosis. Although mitochondria play an important role in generating energy in cardiomyocytes, the relationship between cardiac mitochondria and the VO 2 time constant has not been elucidated. Methods We calculated the ratio of abnormal cardiac mitochondria in human myocardial biopsy samples using an electron microscope and measured the VO 2 time constant during cardiopulmonary exercise testing. The VO 2 time constant was normalized by the fat-free mass index (FFMI). Patients Fifteen patients with non-ischemic cardiomyopathy (NICM) were included. Patients were divided into two groups according to their median VO 2 time constant/FFMI value. Results Patients with a low VO 2 time constant/FFMI value had a lower abnormal mitochondria ratio than those with a high VO 2 time constant/FFMI value. A multiple linear regression analysis revealed that the ratio of abnormal cardiac mitochondria was independently associated with a high VO 2 time constant/FFMI. Conclusion An increased abnormal cardiac mitochondria ratio might be associated with a high VO 2 time constant/FFMI value in patients with NICM.

A 56-year-old woman was referred to our hospital for the further evaluation of drug-refractory heart failure with a reduced ejection fraction. A family history interview revealed that men in her family had died of Duchenne muscular dystrophy (DMD), whereas she had no skeletal muscle disorder. Myocardial histopathology revealed a reduced dystrophin expression in the cardiomyocyte membrane, and a dystrophin (DMD) gene analysis identified a duplication in exon 8-9 on Xp21, suggesting that she had a cardiac-specific phenotype of dystrophinopathy, i.e. X-linked dilated cardiomyopathy (XLDCM). In conclusion, careful family history interviews and an investigation of dystrophinopathy are required to detect XLDCM in women.

Implantation of a cardiac resynchronization therapy (CRT) device is usually scheduled in the compensated phase of heart failure; however, procedural safety may be sometimes disturbed in the decompensated phase. We report a case of a successful semi-urgent implantation of a CRT device temporary assisted with Impella in a patient with the decompensated phase of severe heart failure dependent on inotropic agents and who cannot maintain the supine position. Impella assistance with left ventricular (LV) unloading and maintenance of end-organ perfusion contributed to early recovery from acute heart failure. Furthermore, an acute effect of mechanical resynchronization by biventricular pacing plays an important role in weaning from the mechanical support or inotropic dependence. These mutual effects of mechanical support and CRT might contribute to a decrease in LV end-diastolic pressure and to a remarkable early recovery from a severely decompensated condition.

Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose.

Although multiple myeloma (MM) had been an incurable hematological malignancy with a poor prognosis, recent advances in novel anti-neoplastic agents, including carfilzomib (a proteasome inhibitor), have improved the prognosis. We herein report two cases of congestive heart failure in patients treated with carfilzomib. Although there are some reports on the cardiotoxicity of carfilzomib, to our knowledge, this is the first report on the cardiac involvement of carfilzomib in Japanese MM patients. We review the critical points from our two cases, with the aim of avoiding carfilzomib-associated heart failure in MM patients.

Background: Following heart transplantation (Tx), recipients are closely monitored using endomyocardial biopsy, which is limited by cost and invasiveness, and echocardiography, which is limited regarding detailed structural and functional evaluation., Purpose: To test the feasibility of comprehensive structure-function cardiac MRI as a noninvasive modality to assess changes in myocardial structure and function., Study Type: Prospective., Subjects: MR was performed in 61 heart transplant recipients (age 47.9 ± 16.3 years, 39% female) and 14 age-matched healthy controls (age 47.7 ± 16.7 years, 36% female)., Field Strength/sequence: 1.5T; 2D CINE steady state free precession (SSF)P imaging, T 2 -mapping, pre- and postgadolinium contrast T 1 -mapping, and tissue-phase mapping (TPM)., Assessment: Quantification of myocardial T 2 (as a measure of edema), pre- and post-Gd T 1 (allowing calculation of extracellular volume (ECV) to estimate interstitial expansion), and TPM-based assessment of peak regional left ventricular (LV) velocities, dyssynchrony, and twist., Statistical Tests: Comparisons between transplant recipients and controls were performed using independent samples t-tests. Relationships between structural (T 2 , T 1 , ECV) and functional measures (myocardial velocities, dyssynchrony, twist) were assessed using Pearson correlation analysis., Results: T 2 and T 1 were significantly elevated in transplant recipients compared to controls (global T 2 : 50.5 ± 3.4 msec vs. 45.2 ± 2.3 msec, P < 0.01; global T 1 : 1037.8 ± 48.0 msec vs. 993.8 ± 34.1 msec, P < 0.01). Systolic longitudinal function was impaired in transplant recipients compared to controls (reduced peak systolic longitudinal velocities, 2.9 ± 1.1 cm/s vs. 5.1 ± 1.2 cm/s, P < 0.01; elevated systolic longitudinal dyssynchrony, 60.2 ± 30.2 msec vs. 32.1 ± 25.1 msec, P < 0.01). Correlation analysis revealed a significant positive relationship between T 2 and ECV (r = 0.45,P < 0.01). In addition, peak systolic longitudinal velocities demonstrated a significant inverse relationship with T 2 (global r = -0.29, P = 0.02), and systolic radial dyssynchrony was positively associated with peak T 2 and peak T 1 (r = 0.26,P = 0.04; r = 0.27,P = 0.03)., Data Conclusion: MR techniques are sensitive to structural and functional differences in transplant recipients compared to controls. Structural (T 2 , T 1 ) and functional (peak myocardial velocities, dyssynchrony) measures were significantly associated, suggesting a structure-function relationship of cardiac abnormalities following heart transplant., Level of Evidence: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:678-687., (© 2018 International Society for Magnetic Resonance in Medicine.)

Purpose: To evaluate the local specific absorption rate (SAR) and heating around retained cardiac leads during MRI at 64 MHz (1.5T) and 127 MHz (3T) as a function of RF coil type and imaging landmark., Methods: Numerical models of retained cardiac leads were built from CT and X-ray images of 6 patients with retained cardiac leads. Electromagnetic simulations and bio-heat modeling were performed with MRI RF body and head coils tuned to 64 MHz and 127 MHz and positioned at 9 different imaging landmarks covering an area from the head to the lower limbs., Results: For all patients and at both 1.5T and 3T, local transmit head coils produced negligible temperature rise ( Δ T < 0.1 ° C ) for ‖ ‖ B 1 + ‖ ‖ ≤ 3   μ T . For body imaging with quadrature-driven coils at 1.5T, Δ T during a 10-min scan remained < 3°C at all imaging landmarks for ‖ ‖ B 1 + ‖ ‖ ≤ 3   μ T and <6°C for ‖ ‖ B 1 + ‖ ‖ ≤ 4   μ T . For body imaging at 3T, Δ T during a 10-min scan remained < 6°C at all imaging landmarks for ‖ ‖ B 1 + ‖ ‖ ≤ 2   μ T . For shorter pulse sequences up to 2 min, Δ T remained < 6°C for ‖ ‖ B 1 + ‖ ‖ ≤ 3   μ T ., Conclusion: For the models based on 6 patients studied, simulations suggest that MRI could be performed safely using a local head coil at both 1.5T and 3T, and with a body coil at 1.5T with pulses that produced ‖ ‖ B 1 + ‖ ‖ ≤ 4   μ T . MRI at 3T could be performed safely in these patients using pulses with ‖ ‖ B 1 + ‖ ‖ ≤ 2   μ T ., (© 2018 International Society for Magnetic Resonance in Medicine.)

Background Hypertrophic obstructive cardiomyopathy (HOCM) is sometimes concomitant with atrial fibrillation (AF) and exacerbates heart failure symptoms. Although optimal medication for the reduction of left ventricular outflow tract (LVOT) obstruction and the maintenance of sinus rhythm should be considered, it is difficult to control the symptoms permanently. Case summary A 45-year-old man, diagnosed with HOCM, presented with progressive dyspnoea on exertion, which significantly deteriorated during episodes of paroxysmal AF, despite optimal medical therapy. On echocardiography, we found LVOT obstruction with a peak pressure gradient of 98 mmHg, concomitant with redundant mitral valve leaflets, which caused significant systolic anterior motion (SAM). Since he declined open surgery, we selected a combination of catheter interventions, AF ablation, and alcohol septal ablation (ASA). After the AF ablation, the occurrence of AF significantly decreased, and there was no recurrence after the ASA. By 6 months, the plasma N-terminal pro-B-type natriuretic peptide level had decreased from 1022 to 124 pg/mL, the peak pressure gradient of LVOT decreased from 98 to 12 mmHg, and the left atrium volume decreased from 203 to 178.4 mL. The improvement in the SAM was visualized on echocardiography and was haemodynamically corroborated by the four-dimensional (4D)-flow cardiac magnetic resonance (CMR). Discussion The treatment of drug-refractory HOCM concomitant with paroxysmal AF needs both septal reduction and the maintenance of sinus rhythm, which can be accomplished through transcatheter interventions. Moreover, the detailed intra-ventricular haemodynamic assessment in HOCM patients can be explored using the 4D-flow CMR. [ABSTRACT FROM AUTHOR]