[Clinical evaluation of intraoperative cardiac output measurement by a new arterial pressure waveform analysis method( FloTrac/Vigileo) in open heart surgery].

We retrospectively evaluated the initial clinical experience of intraoperative cardiac output measurement by a new arterial pressure-based cardiac output (APCO:FloTrac/Vigileo) analysis in patients undergoing open heart surgery. Thirty-two patients (mean age 76.4, range 59 to 90)who underwent cardiac surgery under cardiopulmonary bypass( CPB) from July 2008 to September 2009 in our institute were enrolled in this study. There were 14 women and 18 men. The cardiac operations included 28 valve surgeries and 4 coronary artery bypass grafting. The APCO was introduced initially, then a continuous cardiac output (CCO:Swan-Ganz catheter) analysis system was established following the induction of anesthesia. The correlation of both cardiac output measurements was evaluated at 5 time points, T1:induction of anesthesia, T2:sternotomy, T3:after weaning from CPB, T4:closure of the chest, and T5:arrival at intensive care unit. There were no serious complications related to APCO and CCO. The correlation between APCO and CCO was evaluated by Bland-Altman plot analysis. The percentages of correlation between both groups were T1:81.2%, T2:78.1%, T3:59.4%, T4:62.5%, and T5:65.6%. A good correlation was shown in all 6 patients with atrial fibrillation at T1 and T2. No correlation was shown in the 3 patients with left ventricular( LV) dysfunction below LVEF 40%, 1 case at T3, all 3 cases at T4, and 2 cases at T5. Before the institution of CPB, 3 of the 6 at T1 and 3 of the 7 at T2 in whom no correlation was shown, had severe aortic valve insufficiency (AVI).From these results, APCO appears to be an acceptable device to evaluate the intraoperative cardiac output measurement compared with CCO, except in patients with LV dysfunction or AVI at some time points. Further studies will be necessary to elucidate the precise clinical evidence to assess the efficacy of this new analysis device.

[Open heart surgery in a patient with a history of Takotsubo cardiomyopathy].

An 81-year-old man had a history of Takotsubo cardiomyopathy induced by general fatigue after travel and acute gastritis 2 years previously. Recently, dyspnea on effort had been worsening. Since preoperative echocardiography showed severe aortic valve regurgitation (AR) with left ventricular (LV) dilatation, aortic valve replacement (AVR) by the standard procedure was indicated. Since the safety of the perioperative clinical course including recurrence of Takotsubo syndrome and hemodynamic compromise was unclear, a thorough examination was performed before surgical intervention. AVR with a 21 mm Mosaic bioprosthesis was performed. Transesophageal echocardiography (TEE) during operation did not demonstrate any sign of Takotsubo syndrome and good LV function was maintained. The patient was discharged on postoperative day 18 without any cardiac events including arrhythmia or clinical symptoms such as chest pain. Based on these results, open heart surgery under cardiopulmonary bypass (CPB) and cardiac arrest could be safely performed in patients with a history of Takotsubo cardiomyopathy with minimum use of cardiac agents including cathecholamine and sufficient perioperative removal of emotional and physical stress.