Munehito Arimoto

Safety and efficacy of landiolol hydrochloride for prevention of atrial fibrillation after cardiac surgery in patients with left ventricular dysfunction: Prevention of Atrial Fibrillation After Cardiac Surgery With Landiolol Hydrochloride for Left Ventricular Dysfunction (PLATON) trial.

OBJECTIVES We previously conducted a prospective study of landiolol hydrochloride (INN landiolol), an ultrashort-acting β-blocker, and reported that it could prevent atrial fibrillation after cardiac surgery. This trial was performed to investigate the safety and efficacy of landiolol hydrochloride in patients with left ventricular dysfunction undergoing cardiac surgery. METHODS Sixty patients with a preoperative left ventricular ejection fraction of less than 35% were randomly assigned to 2 groups before cardiac surgery and then received intravenous infusion with landiolol hydrochloride (landiolol group) or without landiolol (control group). The primary end point was occurrence of atrial fibrillation as much as 1 week postoperatively. The secondary end points were blood pressure, heart rate, intensive care unit and hospital stays, ventilation time, ejection fraction, biomarkers of ischemia, and brain natriuretic peptide. RESULTS Atrial fibrillation occurred in 3 patients (10%) in the landiolol group versus 12 (40%) in the control group, and its frequency was significantly lower in the landiolol group (P = .002). During the early postoperative period, levels of brain natriuretic peptide and ischemic biomarkers were significantly lower in the landiolol group than the control group. The landiolol group also had a significantly shorter hospital stay (P = .019). Intravenous infusion was not discontinued for hypotension or bradycardia in either group. CONCLUSIONS Low-dose infusion of landiolol hydrochloride prevented atrial fibrillation after cardiac surgery in patients with cardiac dysfunction and was safe, with no effect on blood pressure. This intravenous β-blocker seems useful for perioperative management of cardiac surgical patients with left ventricular dysfunction.

Changeover Trial of Azilsartan and Olmesartan Comparing Effects on the Renin-Angiotensin-Aldosterone System in Patients with Essential Hypertension after Cardiac Surgery (CHAOS Study).

BACKGROUND Angiotensin II receptor blockers (ARBs) have been widely used to treat hypertension and large-scale clinical studies have shown various benefits. In this study, we compared olmesartan with azilsartan, the newest ARB. METHODS The subjects were outpatients who were clinically stable after cardiac surgery. Sixty patients were randomized to receive either azilsartan or olmesartan for 1 year and were switched to the other drug for the following 1 year. The primary endpoints were the levels of plasma renin activity, angiotensin II, and aldosterone. RESULTS Home blood pressure exceeded 140/90 mmHg and additional antihypertensive medication was administered to 12 patients (20 episodes) in the azilsartan group versus 4 patients (4 episodes) in the olmesartan group, with the number being significantly higher in the azilsartan group. After 1 year of treatment, both angiotensin II and aldosterone levels were significantly lower in the olmesartan group than the azilsartan group. Left ventricular mass index was also significantly lower in the olmesartan group than the azilsartan group. CONCLUSION This study showed that olmesartan reduces angiotensin II and aldosterone levels more effectively than azilsartan. Accordingly, it may be effective in patients with increased renin-angiotensin-aldosterone system activity after cardiac surgery or patients with severe cardiac hypertrophy.

Giant Thrombus Formation Immediately After Mitral Valvuloplasty.

Patients with atrial fibrillation (AF) are at risk of cardioembolism.(1,2)) Atrial thrombus formation associated with AF typically occurs in the left atrial appendage (LAA);(3)) therefore, transesophageal echocardiography (TEE) is important for detection of such a thrombus and measurement of LAA flow velocity.(4,5)) LAA closure is routinely performed during mitral valve surgery in patients with AF to prevent cardiogenic stroke.(6)) We report the case of a 65-year-old woman with severe mitral regurgitation (MR) and AF in whom a giant thrombus formed almost immediately after mitral and tricuspid valvuloplasty and concurrent LAA resection. No atrial thrombus or spontaneous echo contrast (SEC) was detected by TEE before the surgery. However, a giant intramural thrombus was detected in the left atrium 7 days after surgery. It was thought that the atrial dysfunction as well as the change in morphology of the left atrium resulting from the severe MR complicated by AF and congestive heart failure produced a thrombotic substrate. This case suggests that careful surveillance for thrombus formation and careful maintenance of anticoagulation therapy are needed throughout the perioperative period even if no SEC or thrombus is detected before surgery.

Early and Long-Term Outcomes in Japanese Patients Aged 80 Years or Older Undergoing Conventional Aortic Valve Replacement.

UNLABELLED In this study, we investigated the early and long-term results of conventional aortic valve replacement (AVR) in very old patients. METHODS Seventy-five patients with aortic stenosis underwent conventional AVR for patients aged 80 years.We examined early death and major adverse cardiovascular and cerebrovascular event (MACCE). RESULTS The operative mortality was 0% for isolated AVR and 19.2% for concomitant surgery. The postoperative survival rate and MACCE free-rate were no significant differences between the isolated AVR and the concomitant surgery. Univariate analysis confirmed that cardiac dysfunction, severe chronic kidney disease (CKD), hemodialysis, + coronary artery bypass grafting, and norepinephrine use were risk factor of early death. Univariate analysis confirmed that severe CKD, BNP >1000 pg/ml, aortic cross clamping time (ACCT) >180 min, and non-use carperitide and multivariate analysis confirmed that ACCT >180 min, and non-use carperitide were risk factor of MACCE. CONCLUSIONS This study showed that the results of conventional AVR in very old patients were not satisfactory. However, the results obtained with isolated AVR were favorable with no operative deaths. The present study demonstrated that preoperative cardiac function, preoperative renal function, and operative factors have an important impact on early mortality and MACCE.

Safety of The Direct Oral Anticoagulant Edoxaban for Atrial Fibrillation After Cardiac Surgery: Pilot Study

Direct oral anticoagulants have recently been recommended for non-valvular atrial fibrillation, but have rarely been studied in the field of cardiac surgery. We prospectively investigated the safety of edoxaban, a novel oral anticoagulant, for use in cardiac surgery patients with postoperative atrial fibrillation (POAF), which is the most common complication of cardiac surgery and can lead to stroke. The subjects were adult cardiac surgery patients with POAF who received oral edoxaban for 2 months in an open-label pilot study. The primary endpoint was cerebrovascular/bleeding events up to 2 months, while the secondary endpoints were hemoglobin, prothrombin time, and activated partial thromboplastin time. There were no cerebrovascular or bleeding events during edoxaban treatment and the test drug was not discontinued by any patient. There was no macroscopic hematuria and hemoglobin did not decrease, being significantly higher than the baseline level after 2 months. The prothrombin time was significantly prolonged from 1 week to 2 months and the activated partial thromboplastin time was significantly prolonged from 1 day to 2 months. Echocardiography detected pericardial effusion in 1 patient, but hemoglobin did not decrease and the effusion improved with diuretic therapy. In conclusion, despite the limited sample size of this pilot study, it was demonstrated that edoxaban does not induce bleeding in patients with POAF after cardiac surgery, suggesting that it is safe to perform a large-scale efficacy study of edoxaban as anticoagulant therapy for POAF.

Sleep disordered breathing in cardiac surgery patients: The NU-SLEEP trial

BACKGROUND Sleep disordered breathing (SDB) is associated with lifestyle-related diseases and its treatment influence the prognosis of cardiac disease, but little investigation of SDB has been conducted in cardiac surgery patients. METHODS AND RESULTS A prospective study was performed in 1005 patients undergoing cardiac surgery. The primary endpoint was the severity of SDB determined from the apnea/hypopnea index. The secondary endpoints were patient background factors, cardiovascular risk factors, ejection fraction, atrial and brain natriuretic peptides, oxidative stress and inflammatory markers, and postoperative atrial fibrillation. While 227 patients (22.6%) did not have SDB, there were 361 patients (35.9%) with mild SDB, 260 patients (25.9%) with moderate SDB, and 157 patients (15.6%) with severe SDB. Patients with severe SDB had a lower ejection fraction and higher levels of atrial and brain natriuretic peptides than the other groups. Postoperative atrial fibrillation occurred in 28 patients without SDB (13.6%), 43 patients with mild SDB (13.5%), 74 patients with moderate SDB (31.9%), and 73 patients with severe SDB (52.5%), being significantly more frequent in the severe group than the other groups. CONCLUSIONS SDB was frequent in cardiac surgery patients. Activation of the renin-angiotensin-aldosterone system, postoperative atrial fibrillation atrial, and cardiac dysfunction were associated with severe SDB. Markers of inflammation and oxidative stress also increased as SDB became more severe.

New Treatment for Infection of the NIPRO LVAD Cannula Site: Nihon University Crystal Violet Method

Driveline and cannula site infections are still a frequent adverse event in patients with a ventricular assist device (VAD), and it is important to treat and prevent them because the spread of local infection may cause sepsis in some cases. We report our experience with a patient in whom infection of the NIPRO LVAD cannula site after implantation of an extracorporeal VAD was controlled by treatment with crystal violet Solbase (Nihon University crystal violet method).

New Treatment for Percutaneous Sites in Patients with a Ventricular Assist Device: Nihon University Crystal Violet Method.

BACKGROUND Infection of the percutaneous site of a ventricular assist device (VAD) is a challenging complication. We report our experience with crystal violet Solbase (Nihon University crystal violet method) for prevention of driveline or cannula infections in VAD patients. PATIENTS AND METHODS The crystal violet method was used in 10 patients (prophylaxis in nine and treatment in one). Eight patients had an extracorporeal VAD (Nipro) and two had an implantable VAD (Heart Mate II). RESULTS The infection-free period was 4-623 days (mean: 144.2 ± 222.9 days). All eight patients with an extracorporeal VAD died, while the two patients with an implantable VAD (Heart Mate II) survived. Infection was improved in a patient with MRSA, and the results of bacteriological examination were always negative in the patients receiving prophylaxis. The two patients with an implantable VAD had no infection for 2 and 20 months after implantation. CONCLUSION These findings suggest that the Nihon University crystal violet method is effective for prevention and treatment of driveline or cannula infections in patients with a VAD.

Long-Term Outcome of Prosthetic Valve Replacement in Japanese Patients Aged 65 Years or Older: Are Guidelines for Prosthetic Valve Selection Based on Overseas Data Appropriate for Japanese Patients?

BACKGROUND Based on the revised AHA/ACC guidelines, it might be necessary to take into consideration the average life expectancy of Japanese people and revise the Japanese guidelines accordingly. Accordingly, we performed the present study to compare the long-term outcome in patients aged 65 years or older who underwent prosthetic valve replacement at our hospital using mechanical valves or biological valves. METHODS We have performed valve replacement in 416 patients aged 65 years or older (mechanical: 157; biological: 244). RESULTS There was no significant difference between the mechanical and biological valve for the actuarial survival rate. As for the valve-related complication free rate, in the mechanical valve group, the rates were significantly higher for all patients, aortic valve replacement (AVR) patients, and mitral valve replacement (MVR) patients. CONCLUSIONS Following revision of the AHA/ACC guidelines for selection of prosthetic valves, it is necessary to investigate whether patients aged 60-70 represent the gray zone for selecting valves as in US and European guidelines, or whether a higher age is more appropriate in view of the longer average life expectancy in Japan. Accordingly, further evaluation of the long-term outcome for mechanical and biological valves in Japanese patients is needed to obtain evidence for preparation of original Japanese guidelines on prosthetic valve selection.

Calcified Amorphous Tumor-Induced Acute Cerebral Infarction: A Case Report and Histopathologic Comparison of Calcified Amorphous Tumor and Mitral Annular Calcification

We report the case of a 38-year-old woman who was admitted for acute cerebral infarction linked to a cardiac calcified amorphous tumor (CAT) and related mitral annular calcification (MAC). The cardiac mass was removed, and mitral valve replacement surgery was performed. Pathological examination revealed an amorphous accumulation of degenerating material within both lesions, indicating that build-up of calcium along the mitral annulus and subsequent rupture of the fibrotic tissue may be involved in the initiation and progression of CAT.