Amiodarone-Induced Hyponatremia Masked by Tolvaptan in a Patient with an Implantable Left Ventricular Assist Device.

A 43-year-old man was referred to our hospital in June 2014 because of severe heart failure. He was diagnosed with familial dilated cardiomyopathy and was administered oral tolvaptan and amiodarone for atrial and ventricular tachycardia. Since up-titration of carvedilol had failed and he was dependent on dobutamine, a left ventricular assist device (LVAD) was implanted. Tolvaptan and furosemide were both discontinued after LVAD implantation and he was discharged from the hospital. Thirteen months later, he was hospitalized for lethargy and hyponatremia of 108 mEq/L, with an antidiuretic hormone level of 2.5 pg/mL, which suggested syndrome of inappropriate antidiuretic hormone secretion (SIADH). We discontinued amiodarone and administered fludrocortisones. However, hyponatremia persisted for a few more days, eventually resulting in delirium and damage to the LVAD driveline. He received an urgent pump exchange and hyponatremia was gradually improved. We considered the possibility that amiodarone-induced SIADH was masked by tolvaptan therapy before LVAD implantation.

[Concomitant Surgery for Symptomatic Severe Carotid Artery Stenosis and Aortic Valve Stenosis with Contralateral Internal Carotid Artery Occlusion:A Case Report].

We report a case of concomitant carotid endarterectomy(CEA)and aortic valve replacement(AVR)for symptomatic severe carotid artery and aortic valve stenosis(AS). A 77-year-old man, presented to our hospital with AS complicated by right internal carotid artery(ICA)stenosis and left ICA occlusion, seeking treatment for AS. He suffered from left hemiparesis, and diffusion-weighted magnetic resonance imaging(MRI)showed multiple ischemic lesions in the right cerebral hemisphere. He was admitted to our neurosurgical department and received treatment for acute cerebral infarction caused by severe right ICA stenosis. The symptomatic severe right ICA stenosis was an indication for surgical treatment, but simple carotid revascularization of the stenosed ICA was considered to be deteriorated the cardiac function due to untreated AS. Thus, we decided to perform concomitant carotid and valvular surgery. The patient underwent a combined CEA and AVR procedure with the introduction of an intraoperative intra-aortic balloon pump. His postoperative course was uneventful even 12 months after the surgery. Management and surgical strategies for patients with concomitant ICA stenosis and AS continue to be controversial subjects. Combined carotid and cardiac valve surgery is considered to be effective in such cases, and we discuss its implications and review of literature.

[L-shaped Partial Upper Sternotomy Approach for Aortic Valve Replacement].

Transcatheter aortic valve implantation is a recent innovation in the treatment of severe aortic stenosis. On the other hand, several reports suggested that minimally invasive aortic valve replacement (MICS-AVR) is likely to be associated with reduced postoperative discomfort and faster recovery. Of note, an upper partial sternotomy for isolated aortic valve replacement( L-shaped MICS-AVR) has been accepted as the most common approach to the MICS-AVR. Since October 2013, we have preformed L-shaped MICS-AVR at our hospital. In L-shaped MICS-AVR group(16 patients, 74.4±8.7 years),there was no operative mortality and any other complication including reexploration for postoperative bleeding, wound infection, peri-valvular leakage, pulmonary complication like re-intubation or minitracheostomy. To demonstrate the benefits of this approach, over-octogenarian subgroup( n=7)was analyzed and compared with the isolated AVR using a conventional sternotomy (C-AVR, n=10)in the same period. A trend was seen toward better postoperative course in the L-shaped MICS-AVR group than in the C-AVR group;however, this difference was not statistically significant. The mean duration of cardiopulmonary bypass(120±29 min vs 93±24 min, p=0.005)and cross clamp time(151±36 min vs 124±32 min, p=0.038)were significantly longer than C-AVR. We believe that more clinical experience is required to clarify the benefits of this approach and we must more consider the preoperative images for the attainment of the excellent exposure. Moreover, the concomitant use of this new device and L-shaped MICS-AVR may enable a big improvement in the future.

Successful surgical treatment of traumatic sternal fracture with extensive mediastinal abscess and concomitant mitral valve endocarditis: a case report.

BACKGROUND: A traumatic sternal fracture with extensive mediastinal abscess and concomitant native valve endocarditis is an extremely rare but catastrophic situation. CASE PRESENTATION: For 2 weeks, the co-infected patient was treated with aggressive debridement for the mediastinitis, change of vacuum-assisted closure therapy dressings, vegetectomy and valve repair through lower partial sternotomy, and delayed primary wound closure. CONCLUSIONS: To the best of our knowledge, this successful staged strategy has not been previously reported. We believe that our quick decision about repeated surgical interventions and preservation of the manubrium led to a favorable result.

Rescue balloon pulmonary angioplasty under veno-arterial extracorporeal membrane oxygenation in a patient with acute exacerbation of chronic thromboembolic pulmonary hypertension.

We describe a case of a 41-year-old woman with acute exacerbation of chronic thromboembolic pulmonary hypertension (CTEPH) complicated by rapidly progressive respiratory failure and right heart failure with cardiogenic shock. A computed tomography (CT) showed thrombi in the right main pulmonary artery and bilateral peripheral pulmonary arteries, and echocardiography showed right ventricular dilatation and tricuspid regurgitation, with an estimated pressure gradient of 80 mmHg. The patient was initially diagnosed with acute pulmonary thromboembolism, and thrombolytic therapy was administered. Her condition subsequently deteriorated, however, necessitating mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We performed emergency catheter-directed thrombectomy and thrombus aspiration. Pulmonary hypertension (PH) temporarily improved, but subsequently worsened, and the patient was diagnosed with CTEPH. Pulmonary endarterectomy (PEA) was performed. After PEA, we were unable to wean the patient off VA-ECMO, and rescue balloon pulmonary angioplasty (BPA) to the middle and inferior lobe branches of the right lung was performed. Five days after BPA, the patient was removed from VA-ECMO and on the 57th day of hospitalization, she was weaned off the ventilator. The patient was discharged after 139 days of hospitalization. Rescue BPA represents a useful intervention for improving PH and weaning off VA-ECMO in a patient with acute exacerbation of CTEPH.

[Aortic root replacement with the freestyle stentless bioprosthesis for infective endocarditis associated with aortic annular destruction].

Treatment of infective endocarditis (IE) associated with aortic annular destruction remains a formidable surgical challenge. Discussions about the optimum modality for reconstruction are still continuing. In such severe endocarditis, we have performed aortic root replacement using the Freestyle stentless bioprosthesis with the full root technique. From 2005 through 2012, 11 patients who had aortic valve endocarditis with annular destruction underwent aortic root replacement at our institute. All of them were treated with the Freestyle stentless bioprosthesis. Their mean age was 69.9 years, and 8 patients were men. Two patients had native valve endocarditis and 9 patients had prosthetic valve endocarditis. Despite appropriate antibiotic therapy, 3 patients required emergency surgery because of hemodynamic deterioration. In-hospital death occurred in 1 patient due to progressive hemodynamic failure. The 10 hospital survivors were followed up for a mean of 27.7±23.1 months (range 5 to 82). Although late death occurred in 2 patients, recurrent IE was not observed in any patients during the follow-up. The results of our study suggest that the Freestyle stentless bioprosthesis could be an excellent alternative to a homograft in the treatment of infective endocarditis associated with aortic annular destruction.

[Primary cardiac angiosarcoma in the right atrium with cardiac tamponade].

Primary cardiac angiosarcoma is very rare with an incidence of 0.0017∼0.19% in collected autopsy series, and its prognosis has been reported as being extremely poor( average survival of 6∼9 months). A 56-year-old man was referred to our hospital with cardiac tamponade caused by right atrial angiosarcoma, after initially being misdiagnosed as acute type A dissection. Echocardiography and chest computed tomography (CT) revealed a pedunculated tumor with a broad base which was originating from the right atrial wall and extended into atrio-ventricular (AV) groove. The tumor was completely resected, and a bovine pericardium patch was used for cardiac reconstruction. Histological examination showed angiosarcoma and a sign of radical excision. The patient, who made an uneventful recovery,was given postoperative radiotherapy and chemotherapy. He died of multiple systemic metastases 14 months postoperatively despite of multidisciplinary treatment. We discuss the therapeutic strategies available for this highly malignant cardiac tumor.

[Completion bentall procedure after aortic valve replacement].

A 51-year-old man, who had undergone aortic valve replacement with a mechanical valve 30 years ago, was referred to our hospital due to acute type A aortic dissection. Pre- and intra-operative echocardiographic evaluation showed no evidence of valve dysfunction or paravalvular leak. Intraoperative inspection revealed a thin pannus covering the leaflet housing of the mechanical valve, which we easily removed. We performed aortic root replacement while leaving the valve in situ, and total aortic arch replacement using elephant trunk technique under hypothermic circulatory arrest. He was discharged from the hospital 31 days after operation and retains normal valve function. For patients with aneurysms and acute type A aortic dissection having aortic valve prosthesis that does not require replacement, the completion Bentall procedure is a more secure and safer repair than complete aortic root reconstruction.

[Bentall operation for a 90-year-old man with root aneurysm; report of a case].

Open heart surgery in nonagenarians is not common. We reported a successful Bentall operation in a 90-year-old man with aortic root aneurysm and aortic regurgitation. He has lived healthfully and independently without a big problem. He was referred to our hospital for acute heart failure. The aortic root enlarged as a diameter of 60 mm and moderate aortic regurgitation were recognized by echocardiography and aortogram. We excised the aneurysm, implanted a composite graft, directly attached the coronary arteries to the aortic graft (Carrel patch technique), and made the distal anastomosis to the divided aorta. Postoperative course was uneventful. To our knowledge, this is the first successful case of Bentall operation for nonagenarians in Japan. If selective criteria identifying risks and benefits for individual patients is applied, the nonagenarian can safely undergo cardiac surgery.