A Case of Refractory Sustained Ventricular Tachycardia with Dilated-Phase Hypertrophic Cardiomyopathy Treated by Left Ventriculotomy / 日本心臓血管外科学会雑誌

A 63-year-old man had been receiving medical treatment for hypertrophic cardiomyopathy (HCM) for 20 years. Sustained ventricular tachycardia (VT) had often occurred over the previous 2 years in spite of the administration of antiarrhythmic drugs. He therefore received an implantable cardioverter defibrillator (ICD). However, his symptoms did not improve thus dilated-phase HCM was diagnosed. Because sustained VT often occurred subsequently, the ICD had to be frequently used. An electrophysiological study (EPS) using the CARTO electroanatomical mapping system revealed the earliest activation site to be in the posterolateral wall of the left ventricle (LV). VT did not stop despite 2 endocardial catheter ablation procedures. Therefore, the VT foci was thought to be a reentry circuit on the epicardial side of the posterolateral LV wall. A part of the posterolateral LV wall that involved the reentry circuit was therefore resected. Since undergoing this surgical procedure, the patient has experienced no recurrence of VT during a follow-up period of 14 months.

Less Invasive Aortic Valve Replacement Following Coronary Artery Bypass Grafting Using the Internal Thoracic Artery: Usefulness of Balloon Occlusion of the Internal Thoracic Artery Graft / 日本心臓血管外科学会雑誌

When performing aortic valve replacement (AVR) in patients with a past history of coronary artery bypass grafting (CABG) using the internal thoracic artery (ITA), the patent ITA graft needs to be detached from the surrounding tissue and occluded to properly protect the myocardium. However, detaching the ITA graft from the surrounding tissue takes time, and caution must be exercised to avoid damaging the graft. Two patients with a past history of CABG using the ITA were scheduled to undergo AVR. To simplify AVR, a balloon was placed preoperatively, and was inflated during aortic occlusion to occlude the ITA graft. The myocardium was adequately protected in this manner. Furthermore, since adhesion detachment was limited to around the ascending aorta, operative duration was short and bleeding volume was low. Balloon occlusion of the ITA graft appears to be useful in reducing the invasiveness of AVR in patients with a past history of CABG.

Aortic Valve Re-Replacement with Aortic Root Enlargement for Aortic Valvular Stenosis after Aortic Valve Implantation with a Freestyle Stentless Porcine Valve / 日本心臓血管外科学会雑誌

We present a successfully treated case of re-operation for aortic valvular stenosis caused by implantation of a stentless prosthesis using oversizing sub-coronary insertion in a young woman. The 17-year-old Japanese woman received aortic valve replacement (AVR) with a 21mm Freestyle stentless porcine valve (Medtronic Inc.), using the oversizing modified sub-coronary insertion because of infectious endocarditis 12 years previously at another hospital. Just after the operation, she suffered severe heart failure. At 16 years old, since a cardiac murmur and dyspnea on effort appeared, and she presented severe heart failure due to significant aortic valvular stenosis with a mean aortic valve gradient 115mmHg, we performed aortic valve re-replacement (ATS AP 18mm) with an aortic root enlargement procedure. Intraoperative findings suggested that the oversizing technique was related to aortic valvular stenosis. The postoperative course has been uneventful.