Akira Sese

Bidirectional Glenn Procedure Improves the Mechanical Efficiency of a Total Cavopulmonary Connection in High-Risk Fontan Candidates

BackgroundA total cavopulmonary connection (TCPC) is a widely performed surgical procedure for Fontan candidates. High-risk candidates who have undergone the bidirectional Glenn procedure (BDG) before TCPC have shown good results. The exact mechanism of this procedure, however, is still poorly understood. We hypothesized that a volume reduction with BDG improved ventricular contractility, thereby optimizing mechanical efficiency after TCPC. Methods and ResultsWe measured percent normal systemic ventricular end-diastolic volume (%N-EDV), contractility (end-systolic elastance; Ees), afterload (effective arterial elastance; Ea), and mechanical efficiency (ventriculoarterial coupling; Ea/Ees) on the basis of the cardiac catheterization data before and after TCPC. Eighteen patients who underwent staged TCPC after BDG (staged group) were compared with 29 patients who underwent primary TCPC (primary group). Ees and Ea were approximated as follows: Ees=mean arterial pressure/minimal ventricular volume, and Ea=maximal ventricular pressure/(maximal ventricular volume−minimal ventricular volume), and Ea/Ees was then calculated. The ventricular volume was normalized with the body surface area. A canine experimental model with conductance catheter was used to validate the accuracy of this approximation of Ees and Ea. %N-EDV decreased after TCPC in both groups. In the staged group, a smaller ventricular volume resulted in better contractility (Ees). Although afterload (Ea) increased in both groups, the increment of Ea was smaller in the staged group. These changes resulted in an improvement of Ea/Ees in the staged group, whereas Ea/Ees increased in the primary group. ConclusionsThe volume reduction of BDG preceding TCPC allows for any afterload mismatch to be corrected, thereby improving ventricular energetics after TCPC.

New technique in the transfer of an anomalously originated left coronary artery to the aorta

A 21-month-old girl with an anomalous origin of the left coronary artery underwent a transfer of the left coronary artery to the aorta using a new technique of coronary prolongation. Because the anomalous left coronary artery arising from the left anterior aspect of the pulmonary trunk was too short to reach the aorta, a simple transfer of the left coronary artery to the aorta was deemed impossible. Therefore, a transfer was performed with the help of a coronary prolongation technique using the cuff of the pulmonary trunk and an aortic flap. The new route of the left coronary artery was established anterior to the pulmonary trunk. Postoperative angiography showed a patent left coronary artery without any narrowing or kinking, as well as an improved contractility of the left ventricle. Postoperative cardiac scintigraphy showed a decreased ischemic area. This technique is thus considered applicable when the orifice of the anomalous left coronary artery is too distant from the aorta for a direct anastomosis.

Coenzyme Q10: The Prophylactic Effect on Low Cardiac Output Following Cardiac Valve Replacement

A randomized, prospective study of the effectiveness of preoperative administration of coenzyme Q10 on the prophylaxis of postoperative low cardiac output state was performed in 50 patients with acquired valvular diseases necessitating valve replacement. There were 25 patients in the treatment group and 25 in the control group. Patients in the treatment group received 30 to 60 mg of coenzyme Q10 orally for six days before operation. Preoperative clinical variables, operative procedures, total cardiopulmonary bypass time, and aortic cross-clamping time were similar for the two groups. Postoperatively, mild to severe low cardiac output state developed in 28 of 50 patients (56%) and necessitated the administration of considerable amounts of inotropic agent. The treatment group showed a significantly lower incidence of low cardiac output state during the recovery period than the control group (p less than 0.05). These results suggest that preoperative administration of coenzyme Q10 will increase the tolerance of human hearts to ischemia during aortic cross-clamping.

Ventricular mechanics in the bidirectional glenn procedure and total cavopulmonary connection

BACKGROUND The time course of ventricular efficiency in Fontan candidates who underwent both the bidirectional Glenn procedure (BDG) and total cavopulmonary connection (TCPC) were analyzed in this study. We previously reported that volume-load reduction of BDG preceding TCPC allowed for any afterload mismatch to be corrected, thereby improving ventricular efficiency after staged TCPC. METHODS We measured percent normal systemic ventricular end-diastolic volume (%N-EDV), contractility (end-systolic elastance [Ees]), afterload (effective arterial elastance [Ea]), and ventricular efficiency (ventriculoarterial coupling [Ea/Ees]) based on cardiac catheterization data before and after both BDG and staged TCPC in 30 patients. Ees and Ea were approximated as follows: Ees = mean arterial pressure/minimal ventricular volume, and Ea = maximal ventricular pressure/(maximal ventricular volume - minimal ventricular volume), and Ea/Ees was then calculated. Ventricular volume was divided by body surface area. RESULTS The %N-EDV decreased both after BDG and after staged TCPC, thus resulting in an improvement of Ees. Although Ea increased both after BDG and after staged TCPC, Ea decreased during the interval between BDG and staged TCPC. These changes resulted in an improvement in Ea/Ees during the interval period and after staged TCPC, although Ea/Ees worsened after BDG. CONCLUSIONS Correction of afterload mismatch during the interval period between BDG and staged TCPC is considered to be one of the most important factors for obtaining excellent clinical results when selecting a staged strategy to treat high-risk Fontan candidates.

Outcomes of cardiac surgery in trisomy 18 patients.

OBJECTIVE The objective was to clarify the outcomes of cardiac surgery in trisomy 18 patients. PATIENTS AND METHODS We analysed 34 consecutive trisomy 18 patients, of whom 21 were males, with cardiac complications. They were divided into patients who underwent cardiac surgery and those who were conservatively treated. We compared rates of survival and discharge alive between two groups. RESULTS The surgery group included nine patients, with six males, who underwent cardiac surgery - intracardiac repair in three patients, pulmonary arterial banding in five patients, and ligation of the ductus in one patient - at median age of 2.2 months, ranging from 0.5 to 9.8, and with median weight of 2.6 kilograms, ranging from 1.5 to 3.2. Cardiac surgery and pre-operative assisted ventilation were hazardous factors leading to death. In the surgery group, cumulative survival rates at 1 month, 6 months, 12 months, and 24 months were 63%, 38%, 25%, and 22%, respectively, compared with 51%, 26%, 9%, and 9% in the conservative group. There was a significant difference (p = 0.002). The cumulative rates of discharge alive at 1 month, 3 months, and 6 months were 0%, 12%, and 65% in the surgery group, which did not differ from the conservative group (p = 0.80). CONCLUSIONS Cardiac surgery contributed to increased survival rate but not the rate of discharge alive in trisomy 18 patients. Cardiac surgery could not prevent all the trisomy 18 patients from death. The indication of cardiac surgery should be carefully individualised to improve the quality of life in trisomy 18 patients and concerned surrounding people.

Mid-term follow-up of the status of Gore-Tex graft after extracardiac conduit Fontan procedure

OBJECTIVE Extracardiac conduit Fontan procedure (ECFP) using Gore-Tex graft has been performed with increasing frequency for the patients with functional single ventricle. However, lack of growth potential and longevity of the conduit are consistent concerns and main points of criticism of the ECFP. In this study, we investigated the mid-term status of the Gore-Tex graft used in the ECFP by comparing the internal diameter of the graft with the inferior vena cava (IVC) diameter at 1 month and 5.2 years after the ECFP. METHODS Of 79 patients who underwent ECFP using Gore-Tex graft between November 1997 and December 2007, 33 patients who had completed cardiac catheterization at 1 month (21-73 days) and 5.2 years (3.3-9.6 years) after the ECFP were included in this study. We measured the internal diameter of the Gore-Tex graft and IVC at both catheterizations retrospectively. RESULTS The size of the Gore-Tex graft used in the ECFP was 16 mm in 17 patients, 18 mm in 9 patients, and 20mm in 7 patients. Laminar flow through the conduits was maintained without any stenosis or kinking of the graft in these 33 patients. No intervention or reoperation related to the extracardiac conduit has been required. There were no significant differences in mean cross-sectional area (CSA) of the conduits at 1 month versus 5.2 years after the ECFP for each conduit size, and no significant changes in the conduit-to-IVC CSA ratio (0.98+/-0.40 vs 0.82+/-0.21 for 16 mm, 1.09+/-0.30 vs 0.92+/-0.33 for 18 mm, and 1.16+/-0.55 vs 0.94+/-0.44 for 20mm conduit). CONCLUSIONS The conduit CSA and conduit-to-IVC CSA ratio remained unchanged in small caliber grafts down to 16 mm at 5.2 years after the ECFP. However, further investigation is necessary to evaluate the fate of the Gore-Tex graft and late hemodynamics in the patients with small conduits after they achieve full somatic growth.

Surgical Results of Anomalous Origin of the Right Pulmonary Artery From the Ascending Aorta Including Reoperation for Infrequent Complications

BACKGROUND We evaluated the results of surgery for an anomalous origin of the right pulmonary artery from the ascending aorta. METHODS From August 1986 to December 2005, 8 children (6 neonates) aged 7 to 180 days (mean, 35 +/- 59 days) with anomalous origin of the right pulmonary artery from the ascending aorta underwent surgical repair at our institute. All except one child, who had the distal form, had the proximal form. Cardiac catheterization showed that the left pulmonary artery to systemic pressure ratio was 1.0 or more. Surgery was performed by direct anastomosis in 7 patients and by graft interposition in 1. RESULTS There were no operative or late deaths. All patients postoperatively underwent cardiac catheterization that showed decreased left pulmonary artery to systemic pressure ratio ranging from 0.2 to 0.6. Follow-up periods ranged from 2 months to 13 years. We undertook reoperations for two infrequent postoperative causes. One patient exhibited significant supravalvar aortic stenosis and required patch enlargement of the ascending aorta 3 years after operation. The other patient (with the distal form) needed a reoperation after 1 month because of progressive stenosis at the anatomic site. Graft interposition was performed, and histopathologic examination showed that the tissue from the stenotic region looked like that of a ductus. CONCLUSIONS We undertook surgical repair for anomalous origin of the right pulmonary artery from the ascending aorta. Pulmonary hypertension was improved in all patients. Careful follow-up was necessary to detect supravalvar aortic and anastomotic stenosis early and late after operation.

Redirection of the Hepatic Venous Flow for the Treatment of Pulmonary Arteriovenous Malformations after Fontan Operation

A 45-month-old boy who had complex cardiac anomalies with interrupted inferior vena cava and polysplenia underwent extracardiac Fontan operation. He redeveloped deep cyanosis postoperatively. Cardiac catheterization showed a preferential flow of the hepatic venous blood to the right lung and arteriovenous malformations (PAVMs) in the left lung. He underwent revision of the conduit to attain balanced hepatic venous drainage with subsequent regression of the PAVMs and disappearance of cyanosis. Our experience shows that deficiency of hepatic venous flow played a crucial role in the development of PAVMs and that redistribution of the flow retained potential to ameliorate the pathological condition.

Longitudinal growth of the autologous vessels above and below the Gore-Tex graft after the extracardiac conduit Fontan procedure

OBJECTIVE Reflecting excellent mid-term outcomes, extracardiac conduit Fontan procedure (ECFP) using Gore-Tex tube graft has been performed with increasing frequency in patients with functional single ventricle. Nevertheless, due to the lack of growth potential of the artificial conduit, the status of the venous pathway along with somatic growth is a continuing concern. In this study, we evaluated the longitudinal growth of the autologous vessels above and below the Gore-Tex graft used in the ECFP. METHODS This study included 34 patients who had completed cardiac catheterisations at 1 month and 5.1 years after the ECFP. The average age, weight and height at the ECFP were 3.8+/-2.5 years (1.8-12.7 years), 12.7+/-4.6 kg (7.4-33.0 kg) and 92.9+/-16.1cm (72.5-153.5 cm), respectively. We measured the vertical lengths of three different parts angiographically: the length between the confluence point of the innominate vein and the anastomotic site of the conduit to the pulmonary artery (SVC-C), the conduit vertical length (C) and the length between the confluence point of the hepatic vein and the conduits anastomotic site to the inferior vena cava (IVC-C). RESULTS We have not observed stenosis or thrombus formation in the conduit or distortion of the conduit or pulmonary artery in any of the cases. No intervention or re-operation related to the extracardiac conduit was required, and laminar flow through the conduit was maintained with efficient Fontan haemodynamics. At 5.1 years after the ECFP, the average weight and height gain were 10.3+/-4.4 kg and 28.5+/-1.9 cm, respectively. The length of SVC-C, C and IVC-C were significantly increased as 124+/-15%, 106+/-7% and 132+/-24%, respectively, compared to the lengths at 1 month after the ECFP. The degree of increase in SVC-C and IVC-C was significantly larger than that in C. CONCLUSIONS Along with the patients somatic growth, longitudinal growth of the autologous vessels above and below the Gore-Tex graft was demonstrated to compensate for the lack of growth potential of the artificial graft.

Haemostatic profile of small children during and following cardiopulmonary bypass

OBJECTIVE We evaluated changes of the haemostatic system during pediatric cardiac surgery during and after cardiopulmonary bypass (CPB). METHOD Twenty-five children under 15 kg of body weight undergoing open-heart surgery were divided into three groups; 9 patients (Group A), no bank blood was used throughout the surgery; 8 patients (Group B), packed red cells were used in the priming of CPB circuit; 8 patients (Group C) in cyanotic condition, for whom surgery was performed without bank blood. CPB caused a significant decrease of platelet counts in all three groups, the levels of which remained similar next morning. RESULTS Platelet counts decreased more significantly in Group C (59+/-27 k/mm3) than in Group A (119+/-42 k/mm3) and B (104+/-27 k/mm3). Platelet function-platelet activating factor test (HemoSTATUS) did not significantly decrease throughout the perioperative period in Group A. HemoSTATUS value decreased during CPB and recovered after CPB in Group B and C. Prothrombin time international ratio (PT-INR) and activated partial thromboplastin time were significantly prolonged just after CPB and recovered until next morning in all three groups. PT-INR was more prolonged in Group C (2.92+/-0.62) than in Group A (2.08+/-0.27) and B (2.42+/-0.42). There was no significant difference in postoperative bleeding for the first 12 hours among the three groups. CONCLUSION Although extreme hemodilution during CPB significantly impairs the coagulation and platelet system, these changes are usually transient and tolerable with minimal postoperative hemorrhage. However, a prolonged CPB and preoperative cyanotic condition may induce a critical decrease of platelet counts and increase postoperative bleeding.