Long-Term Results of Aortic Valve Replacement Using a 19mm Bileaflet Valve / 日本心臓血管外科学会雑誌

We studied cardiac function and outcome long after aortic valve replacement using a 19mm bileaflet valve. The subjects consisted of 10 of 12 patients living 10 or more years after the operation and 7 of 8 living 5-9 years after the operation. We measured the left ventricular ejection fraction (LVEF), %fraction shortening (%FS), left ventricular diastolic dimension (LVDd), systolic dimension (LVDs), PWT, IVST, and LV-aortic pressure gradient (PG) of in 6 patients each in 10 more years after the operation (Group I) and 5-9 years after the operation (Group II) who underwent ultrasonography, and calculated the left ventricular mass index (LVMI). No statistically significant differences were seen in either parameter in either group. Prognosis was 1 cardiac 2 cancer deaths each in 10 or more years after the operation group. The cumulative survival rate was in 85.7% post operative 5-9 years and 72.7% in 10 years. Although cardiac function was maintained in both groups, more observation is needed from now on because the pressure difference or LVMI may increase.

Argon Beam Coagulator as an Adjunct to Surgery in the Treatment of Drug-Resistant Ventricular Tachycardia. Basic Experiments and Clinical Application / 日本心臓血管外科学会雑誌

Surgery and cryoablation have been the preferred method for treating drug resistant ventricular tachycardia (VT). Cryoablation, the therapeutic usefulness of which has been documented in many reported studies, is nevertheless not free from technical difficulaties. The advent of Bard^® System 6000 Argon beam coagulator (ABC) as a new procedure alternative to cryoablation offered us a hope for solving problems with conventionally used techniques. Preliminary experiments with this device on dog myocardium permitted us to determine therapeutically adequate irradiation time and depth of cauterization and to locate an optimum area of myocardium to be coagulated. Based on these experiences, an attempt was made to use ABC as an adjunct to surgery in the surgical treatment of 4 patients with monofocal non-ischemic VT. In 1 of these 4 patients, VT disappeared postoperatively, making use of antiarrythmia drugs quite unnecessary, while in the remaining 3, a marked diminution of ventricular arrhythmia with a consequent reduction of drug dosage was achieved, use of the device thus being judged to be beneficial. These results led to the conclusion that ABC will provide a valuable adjunct to operation in selected cases of VT and, if the probe and other appliances are further refined, can reasonably be anticipated to be used as frequently as cryoablation.