Hiroto Takamatsu

Infective Endocarditis Complicated by Mycotic Aneurysm of a Coronary Artery With a Perforated Mitral Valvular Aneurysm

Mycotic aneurysms are well-documented complications of infective endocarditis and occur frequently in the intracranial arteries. However, mycotic aneurysms of the coronary arteries are very rare, and there are few reports of the management of these lesions. The authors report the case of a 72-year-old woman with coagulase-negative staphylococcal endocarditis involving a perforated aortic valve, a perforated mitral valve aneurysm, and a large mycotic coronary artery aneurysm. After antimicrobial therapy, the patient underwent open-heart surgery with mitral and aortic valve replacement, coronary artery bypass, and resection of the mycotic coronary aneurysm. The authors present detailed serial echocardiograms of the mycotic coronary artery aneurysm, which was subsequently confirmed intraoperatively and pathologically.

Early increase in serum fatty acid binding protein 4 levels in patients with acute myocardial infarction

Background: Acute myocardial infarction (AMI) induces marked activation of the sympathetic nervous system. Fatty acid binding protein 4 (FABP4) is not only an intracellular protein, but also a secreted adipokine that contributes to obesity-related metabolic complications. Here, we examined the role of serum FABP4 as a pathophysiological marker in patients with AMI. Methods and results: We studied 106 patients presenting to the emergency unit with a final diagnosis of AMI, including 12 patients resuscitated from out-of-hospital cardiac arrest (OHCA) caused by ventricular fibrillation. FABP4 levels peaked on admission or just after percutaneous coronary intervention and declined thereafter. Regression analysis revealed no significant correlation between peak FABP4 and peak cardiac troponin T determined by Roche high-sensitive assays (hs-TnT). Notably, FABP4 levels were particularly elevated in AMI patients who were resuscitated from OHCA (median 130.2 ng/mL, interquartile range (IQR) 51.8–243.9 ng/mL) compared with those without OHCA (median 26.1 ng/ml, IQR 17.1–43.4 ng/mL), while hs-TnT levels on admission were not associated with OHCA. Immunohistochemistry of the human heart revealed that FABP4 is abundantly present in adipocytes within myocardial tissue and epicardial adipose tissue. An in vitro study using cultured adipocytes showed that FABP4 is released through a β3-adrenergic receptor (AR)-mediated mechanism. Conclusions: FABP4 levels were significantly elevated during the early hours after the onset of AMI and were robustly increased in OHCA survivors. Together with the finding that FABP4 is released from adipocytes via β3-AR-mediated lipolysis, our data provide a novel hypothesis that serum FABP4 may represent the adrenergic overdrive that accompanies acute cardiovascular disease, including AMI.

Clinical effect of long-term administration of tolvaptan in patients with heart failure and chronic kidney disease

The effectiveness of long-term administration of tolvaptan in heart failure (HF) patients with chronic kidney disease (CKD) has not been fully studied. Hence, in this study, we investigated the effects of chronic administration of tolvaptan on patients with HF and CKD. We consecutively enrolled 31 patients with acute HF syndrome (AHFS) who were administrated tolvaptan as a long-term medication (TLV group). All patients had a history of prior HF admission and CKD. We also consecutively enrolled 27 patients with AHFS, a prior history of HF and CKD (conventional group). We compared renal function and outcomes between the two groups at discharge for AHFS and after 6 months of follow-up. The estimate glomerular filtration rate (eGFR) was maintained at approximately the same level in the TLV group exhibited approximately the same eGFR (-1.1 ± 8.3 mL/min/1.73 m2) but decreased in the conventional group (-7.4 ± 10.4 mL/min/1.73 m2). There was a significant difference in the changes observed in eGFR between the conventional and TLV groups (p = 0.01). There were no significant differences in the frequencies of rehospitalization and death. Long-term administration of tolvaptan may prevent increased renal dysfunction in HF patients with CKD. This conclusion should be confirmed in a large-scale prospective study.