Patency When Grafted to Coronary Stenosis More Than 50% in LIMA-RA-Y Grafts.

BACKGROUND: Recent coronary surgery practice is to graft arterial conduits to more severely stenosed coronary targets than in the past. We aimed to investigate postoperative arterial graft patency with native coronary stenosis at the time of surgery, using the left internal mammary artery and radial artery (RA) as a composite Y graft (LIMA-RA-Y). In the study timeframe, it was routine clinical practice to graft coronary arteries with >50% stenosis. METHODS: Of 464 patients previously reported 1996-1999, 346 who underwent LIMA-RA-Y at the Royal Melbourne Hospital, 76 had postoperative angiograms at the same institution. Each anastomosis was considered separately. For arterial grafts a "string sign" was analysed as being occluded. Predictor of patency was performed with a generalised linear mixed model (GLMM). RESULTS: Seventy-six (76) patients had postoperative angiograms at 5.8±5.4 years (range 0.23-19.4; interquartile range 1.7-10.0) years postoperative; with age at operation 62.5±10.7 years and 3.4±0.8 grafts per patient, 82% were male. Of 256 anastomoses, 230 were to coronary targets >50% stenosis. Overall patency was 84.0% (214/256). For coronary stenosis >50%, patency was 88% (201/230) and varied by coronary territory left anterior descending (LAD) 94% (87/93), circumflex 90% (71/79) and right coronary artery (RCA) 74% (43/58). Interaction for coronary territory was significant (p=0.022). Higher preoperative coronary stenosis predicted higher patency; with odds ratio for improved patency of 1.83 (95% CI 1.51, 2.22), p<0.001 for each 10% increase in stenosis. CONCLUSIONS: Late patency of composite arterial grafts is acceptable when grafted to coronary arteries of greater than 50% stenosis.

RARAY Operation: Operative Description and Early Results for Achieving Total Arterial Coronary Revascularisation.

BACKGROUND: Total arterial revascularisation may prolong postoperative survival following coronary surgery due to avoidance of late saphenous vein graft (SVG) failure leading to ischaemic cardiac events. The left internal mammary artery (LIMA) is routinely used for CABG but harvest may adversely affect lung function and reduce sternal vascular supply. Early experience of a novel reconstruction with exclusive reliance on two radial arteries (RA) joined as a Y graft (RARAY) is presented. METHODS: One RA is anastomosed to the ascending aorta and used to revascularise the left anterior descending artery coronary territory; and a second RA is joined to the first 4-6 cm from the origin, approximating the lateral border of the pulmonary artery and used to revascularise the circumflex and right coronary territories. No LIMA is used. The radial artery was harvested open with diathermy and metal clips and since 2008, all patients received intravenous vasoconstrictors from the commencement of the anaesthetic. RESULTS: From 2002 to 2019, 28 patients underwent RARAY for specific indications of prior use or reasons to avoid LIMA harvest, preservation of lung function, minimisation of bleeding risk from antiplatelet agents and extra length of RA to graft distal coronary targets beyond usual reach for LIMA. There was no RA spasm, no in-hospital death and no patient returned with symptoms of angina. CONCLUSIONS: The early experience of the RARAY operation for three coronary territory revascularisations are satisfactory.

Results of flowmetric assessment of composite Y-grafts and autovenous coronary artery bypass grafts. / Rezul'taty floumetricheskoi otsenki kombinirovannykh I-graftov i autovenoznykh aortokoronarnykh shuntov.

AIM: The purpose of the study was to perform intraoperative assessment of blood flow in coronary bypass grafts of the 'first' and 'third' order according to Calafiore A.M. with the help of the TTFM technique and to compare the obtained results. PATIENTS AND METHODS: This retrospective, single-centre study enrolled a total of 222 patients subjected to coronary artery bypass grafting (CABG) from January to November 2017. Depending on the type of bypass grafting of the posterior interventricular artery (PIVA), the patients were divided into 2 groups. Group One consisted of 108 patients undergoing bypass grafting of the PIVA with the help of combined Y-grafts from the right internal thoracic artery (RTIA). Group Two was composed of 114 patients subjected to autovenous coronary artery bypass grafting of the PIVA. Blood flow was assessed with the help of the VeriQ MediStim® flowmeter after termination of extracorporeal circulation (ECC), at systolic pressure of 100-110 mm Hg. The parameters of blood flow were assessed using the 1.5- and 2-mm probes. In a specially designed protocol we registered the type of the shunt, the bypassed artery, and values of flowmetry parameters. We also evaluated the pattern of the flowmetric curve according to Takemi Handa et al. RESULTS: The obtained findings revealed a statistically significant difference in the values of Qmean (p=0.001), with the PI values in the groups not statistically differing (p=0.14). Thus, in patients with similar parameters influencing the volumetric velocity of blood flow (the degree of proximal stenosis, diameter of the bypassed artery, mean systolic AP and HR) the value of Qmean was higher in the group with coronary artery bypass grafting (CABG), i. e., in the group of the 'first-order' conduits. Therefore, an autovein directly anastomosed to the aorta experiences grater haemodynamic overload, which completely confirms the theory of Calafiore A.M. CONCLUSION: First-order conduits (CABG) appear to experience greater wall strain because of greater haemodynamic overload as compared with third-order conduits (Y-grafts). A composite Y-graft may be an alternative technique of bypass grafting of the basin of the right coronary artery (RCA). A composite Y-graft has greater resistance to wall shear stress than an autovein anastomosed to the aorta.

Suspected Symptomatic Infected Native Aortic Aneurysm Turns Out To Be Aortic Tumour Originating From Metastatic Cancer of Unknown Primary: A Case Report and Review of Literature.

Introduction: The non-specific clinical presentation of a primary aortic tumour may mimic infectious processes. Together with its rarity, this resemblance can complicate timely identification and pose diagnostic challenges. Report: The case of a 77 year old male patient complaining of abdominal pain radiating to the back, fatigue, and loss of appetite for a month, is presented. Contrast enhanced computed tomography showed a 47 mm infrarenal aortic aneurysm with peripheral enhancement. With suspicion of an infected native aortic aneurysm, open aortic repair was performed using a bovine pericardial Y prosthesis. The intra-operative biopsy revealed a malignant undifferentiated neoplasm, which later turned out to originate from metastatic cancer of unknown primary. The patient died six months later following comprehensive and extensive oncological treatment, which included radiotherapy and chemotherapy. Discussion: Given the scarcity of literature and challenges in classification, treatment recommendations rely on a multidisciplinary approach, involving surgery, radiotherapy, and chemotherapy. Despite the lack of established guidelines, early intervention, even in metastatic cases, may improve clinical outcomes. Surgical resection, whenever appropriate, is advocated, as it not only alleviates symptoms, but intra-operative histological sampling also aids in obtaining a definitive diagnosis.

Thrombectomized autologous portal Y-graft inflow construction can be an option in living-donor liver transplantation: a case report.

BACKGROUND: In living-donor liver transplantation (LDLT), portal Y-graft interposition using the recipient's portal vein (PV) bifurcation has been used for right lobe grafts with double PV orifices. We herein report the use of thrombectomized autologous portal Y-graft interposition for a recipient with preoperative portal vein thrombosis (PVT) in a right lobe LDLT with double PV orifices. CASE PRESENTATION: The recipient was a 54-year-old male with end-stage liver disease due to alcoholic liver cirrhosis. There was PV thrombus in the recipient's PV. The living liver donor was his 53-year-old spouse, and a right lobe graft was planned for the transplantation. Since the donor's liver had a type III PV anomaly, autologous portal Y-graft interposition after thrombectomy was planned for PV reconstruction in the LDLT. The portal Y-graft was resected from the recipient and a thrombus extending from the main PV to the right PV branch was removed on the back table. The portal Y-graft was anastomosed to the anterior and posterior portal branches of the right lobe graft. Followed by venous reconstruction, the Y-graft was anastomosed to the recipient's main PV. The operation time was 545 min and the intraoperative blood loss was 1355 ml. The recipient was discharged on postoperative day 13 without any complications. The recipient remains well with the patency of the portal Y-graft one year after the liver transplantation. CONCLUSION: We herein report the successful use of autologous portal Y-graft interposition after thrombectomy on the back table for a recipient with PVT in a right lobe LDLT.

Successful Transcatheter Aortic Valve Replacement Approached Via a Simultaneously Implanted Y-graft Vascular Prosthesis.

Transcatheter aortic valve replacement (TAVR) is mainly performed using the transfemoral (TF) approach. If the TF approach is difficult, the transapical (TA) or transaortic (TAo) approach is used; however, the complication rate is higher in such cases. In this case, abdominal aortic aneurysm (AAA) replacement and TAVR via artificial vessels were performed simultaneously because of anatomical difficulties in stent graft implantation and TF-TAVR for severe aortic stenosis (AS) associated with AAA. Performing TAVR simultaneously with AAA replacement avoids TA- or TAo-TAVR and allows for postoperative management in the absence of AS. Additionally, there is no need to create a new access for TAVR using artificial vessels. Since the long-term results of AAA are better with open surgery than with endovascular aneurysm repair and the age of indication for TAVR is expected to decrease due to valve-in-valve and other factors, simultaneous surgical AAA replacement and TAVR using a Y-graft vascular prosthesis is an effective treatment option when TF-TAVR is difficult to perform.

A novel Fontan Y-graft for interrupted inferior vena cava and azygos continuation.

OBJECTIVES: To evaluate the hemodynamicdynamic advantage of a new Fontan surgical template that is intended for complex single-ventricle patients with interrupted inferior vena cava-azygos and hemi-azygos continuation. The new technique has emerged from a comprehensive pre-surgical simulation campaign conducted to facilitate a balanced hepatic flow and somatic Fontan pathway growth after Kawashima procedure. METHODS: For 9 patients, aged 2 to18 years, majority having poor preoperative oxygen saturation, a pre-surgical computational fluid dynamics customization is conducted. Both the traditional Fontan pathways and the proposed novel Y-graft templates are considered. Numerical model was validated against in vivo phase-contrast magnetic resonance imaging data and in vitro experiments. RESULTS: The proposed template is selected and executed for 6 out of the 9 patients based on its predicted superior hemodynamic performance. Pre-surgical simulations performed for this cohort indicated that flow from the hepatic veins (HEP) do not reach to the desired lung. The novel Y-graft template, customized via a right- or left-sided displacement of the total cavopulmonary connection anastomosis location resulted a drastic increase in HEP flow to the desired lung. Orientation of HEP to azygos direct shunt is found to be important as it can alter the flow pattern from 38% in the caudally located direct shunt to 3% in the cranial configuration with significantly reversed flow. The postoperative measurements prove that oxygen saturation increased significantly (P-value = 0.00009) to normal levels in 1 year follow-up. CONCLUSIONS: The new Y-graft template, if customized for the individual patient, is a viable alternative to the traditional surgical pathways. This template addresses the competing hemodynamic design factors of low physiological venous pressure, high postoperative oxygen saturation, low energy loss and balanced hepatic growth factor distribution possibly assuring adequate lung development. DATE AND NUMBER OF IRB APPROVAL: 25 October 2019, 280011928-604.01.01.

Myocardial revascularization: Tips and tricks for performing a coronary anastomosis.

Coronary artery bypass graft surgery was performed for the first time in the 1960s [(1]). Today, it is still one of the pillars of cardiac surgery and the most common cardiac operation. Many improvements have been developed since it was first introduced, but such operations remain technically challenging. We focus here on the surgical exposure and suture techniques for different grafts and targets. The goal of standardizing surgical techniques is to improve intraoperative and postoperative outcomes, especially for young practitioners.

Comparative Analysis Following Implementation of Two Types of Y-Composite Multiarterial Revascularization Strategies at a Single Academic Institution.

Background We compared early outcomes, at a single academic institution, of implementing full coronary revascularization in coronary artery bypass grafting using multiarterial Y-composite grafts with multiple sequential anastomoses. Methods and Results Clinical records of 425 consecutive patients who underwent coronary artery bypass grafting using Y-grafting with left internal mammary artery and radial artery (Y-RA group) or right internal mammary artery (Y-RIMA group) from 2015 to 2019, were reviewed. These were compared with the institutional experience of isolated coronary artery bypass grafting cases (in situ on pump/off pump) for the same period of time. When comparing the 4 groups, the Y-RIMA/RA groups revealed a higher number of distal anastomosis than the in situ on- or off-pump groups. When the number of distal arterial anastomosis was analyzed, there was a superiority of using the Y-configuration compared with the in situ approach. Moreover, there were no significant differences among groups for mortality and/or major adverse cardiac and cerebrovascular events in hospital or at 30-day follow-up. A subanalysis comparing the Y-RIMA group with the Y-RA group showed that complementary grafts to the Y-construct were required to accomplish full revascularization more frequently in the Y-RIMA group. Full-arterial revascularization was achieved in 92.2% of the Y-RA group and 72.0% of the Y-RIMA group (P<0.001). In 82.8% of the Y-RA group and 30.8% of the Y-RIMA group, revascularization was completed as an anaortic procedure (P<0.001). Conclusions The 2 types of arterial Y-composite grafting were able to be introduced in the routine practice of our institution showing comparable results to the established institutional practice. This procedure allowed for more arterial distal anastomosis to be performed safely without compromising outcomes.

Y-graft modification to the Fontan procedure: Increasingly balanced flow over time.

OBJECTIVE: The use of Y-grafts for Fontan completion is hypothesized to offer more balanced hepatic flow distribution (HFD) and decreased energy losses. The purpose of this study was to evaluate the hemodynamic performance of Y-grafts over time using serial cardiac magnetic resonance data and to compare their performance with extracardiac Fontan connections. METHODS: Ten Fontan patients with commercially available Y-graft connections and serial postoperative cardiac magnetic resonance data were included in this study. Patient-specific computational fluid dynamics simulations were used to estimate HFD and energy losses. Y-graft performance was compared with 3 extracardiac conduit Fontan groups (n = 10 for each) whose follow-up times straddle the Y-graft time points. RESULTS: Y-graft HFD became significantly more balanced over time (deviation from 50% decreased from 18% ± 14% to 8% ± 8%; P = .015). Total cavopulmonary connection resistance did not significantly change. Y-grafts at 3-year follow-up showed more balanced HFD than the extracardiac conduit groups at both the earlier and later follow-up times. Total cavopulmonary connection resistance was not significantly different between any Y-graft or extracardiac conduit group. CONCLUSIONS: Y-grafts showed significantly more balanced HFD over a 3-year follow-up without an increase in total cavopulmonary connection resistance, and therefore may be a valuable option for Fontan completion. Additional follow-up data at longer follow-up times are still needed to thoroughly characterize the potential advantages of Y-graft use.

Total Arch Replacement with Hypothermic Circulatory Arrest, Antegrade Cerebral Perfusion and the Y-graft.

This study examines postoperative morbidity and mortality and long-term survival after total arch replacement (TAR) using deep to moderate hypothermic circulatory arrest (HCA), antegrade cerebral perfusion (ACP), and the Y-graft. Seventy-five patients underwent TAR with the Y graft. Deep to moderate HCA was initiated at 18-22°C. ACP was either initiated immediately (early ACP) or after the distal anastomosis was performed (late ACP). The arch vessels were then serially anastomosed to the individual limbs of the Y-graft. The median age was 66 years (range = 32-82). Etiology of aneurysmal dilatation included 20 (27%) patients with medial degenerations, 25 (33%) with chronic dissections, 14 (19%) with acute dissections, 9 (12%) with atherosclerosis and 2 (3%) with Marfan syndrome. In-hospital mortality was 5%. Neurologic complications occurred in 8 (11%) patients; 2 (3%) had strokes and 6 (8%) had transient neurologic deficits. Patients undergoing TAR with moderate hypothermia had a significantly higher incidence of new-onset renal insufficiency (3 [23%] vs [0%], P < 0.001) and TND (3 (23%) vs 3 (5%), P = 0.028) than the profound and deep hypothermia cohort. Excluding the 1 patient who died intraoperatively, 89% (95%CI: 79-94%) were alive at 1 year, 78% at 5 years (95%CI: 66-86%), and 73% at 10 years (95%CI: 59-82%). The combination of deep to moderate HCA, ACP, and the Y-graft is a safe and reproducible technique. Further inquiry is needed to assess if early ACP provides superior clinical outcomes.

Short-term outcomes of modified Y-graft technique in acute type a aortic dissection using the femoral artery bypass and one minute systemic circulatory arrest technique.

OBJECTIVE: Aortic arch replacement in acute type A aortic dissection patients remains the most challenging cardiovascular operation. Herein, we described our modified Y-graft technique using the Femoral Artery Bypass (FAB) and the One Minute Systemic Circulatory Arrest (OSCA) technique, and assessed the short-term outcomes of the patients. METHODS: Between February 2015 and November 2017, 51 patients with acute type A aortic dissection underwent aortic arch replacement. Among them, 23 patients underwent FAB while 28 patients underwent both FAB and OSCA. The intraoperative data and postoperative follow-up data were recorded. The follow-up data of patients with traditional Y-graft technique were collected from previously reported studies. RESULTS: In the FAB group, two patients died due to pulmonary infection (30-day survival rate, 91.3%), and two patients were paralyzed from the waist down. Hemodialysis was performed for five patients (21.7%) before hospital discharge. Fifteen patients (65.2%) received respiratory support for more than 2-days and eight patients (34.8%) for more than 5-days. These follow-up results were comparable or better than the patients with traditional Y-graft technique. Furthermore, compared to the FAB group, the morbidity due to neurological dysfunction and acute renal failure was significantly reduced in the FAB+OSCA group. Moreover, the respiratory support, length of postoperative stay and ICU stay were shortened. CONCLUSIONS: This study clarified the feasibility of FAB and OSCA technique in modifying Y-graft technique. The acute type A aortic dissection patients showed less surgical complications and favorable short-term outcomes after this surgery.

Long-term results of conjoined unification venoplasty for multiple portal vein branches of the right liver graft in living donor liver transplantations.

Background: Autologous portal vein Y-graft (PYG) interposition has been the standard procedure for reconstruction of double portal vein (PV) orifices of right liver grafts during living donor liver transplantations. However, it has the disadvantage of being vulnerable to anastomotic stenosis. A refined technique of conjoined unification venoplasty (CUV) was developed to secure PV reconstruction. Methods: We reviewed the surgical outcomes in PV reconstructions using CUVs in 21 cases which were followed up for >3 years. Results: The mean age of recipients was 51.7±4.9 years. The model for end-stage liver disease score was 15.3±6.4. The graft-recipient weight ratio was 1.12±0.21. Recipient PYGs were harvested in all cases. All living donors were blood relatives or relatives through marriage with type III PV anomalies. The number of right liver graft PV orifices was two in 19 cases and three in two cases. For the central intervening vein patch, a PV segment was used in six cases, and an autologous greater saphenous vein patch was used in the remaining 15 cases. The 21 patient cohort displayed a 100% 4-year patient survival rate. None of them underwent any PV interventions including interventional stenting. Serial follow-up computed tomography scans revealed that the reconstructed PV showed early reshaping with a stable streamlined configuration for over 3 years. Conclusions: PV reconstruction using the CUV technique appears to be significantly more effective in preventing PV complications. We believe that CUV is a useful technique to reconstruct right liver grafts with multiple PV orifices.

Percutaneous Ankle Reconstruction of Lateral Ligaments.

Chronic ankle instability following ankle sprains causes pain and functional problems such as recurrent giving way. Within the 3 ligaments of the lateral ligament complex, 80% of patients tear the anterior talofibular ligament (ATFL), whereas the other 20% of patients tear the ATFL and calcaneofibular ligament (CFL). Rarely, the posterior talofibular ligament is involved. An incidence of 10% to 30% of patients will fail conservative treatment and result in chronic ankle instability that may require surgical treatment. To date, numerous open surgical procedures for anatomic repair or reconstruction of ATFL and/or CFL provide good clinical results.

21-Year Survival of Left Internal Mammary Artery-Radial Artery-Y Graft.

BACKGROUND: In 1999, Royse et al. reported on the left internal mammary artery, radial artery, Y-graft technique (LIMA-RA-Y), which achieves total arterial revascularization (TAR). However, the most common coronary reconstruction remains LIMA and supplementary saphenous vein grafts (LIMA + SVG). OBJECTIVES: The goal of this study was to conduct a survival comparison of LIMA-RA-Y versus the conventional LIMA + SVG. METHODS: Of the original 464 LIMA-RA-Y patients reported (1996 to 1998), 346 were from the Royal Melbourne Hospital. Survival at June 2017 was compared with a group of 534 patients from 1996 to 2003 from the same institution who received LIMA + SVG, or 5,800 patients who received TAR with different grafting configurations. Propensity score matching (PSM) was performed with 1:1 matching using 26 variables. Comparisons used Kaplan-Meier (KM) and Cox proportional hazards methods. LIMA-RA-Y was compared with LIMA + SVG in which all non-left anterior descending artery grafts were performed with either composite RA or aorta-coronary SVG with no use of right internal mammary artery. We also conducted a comparison of LIMA-RA-Y versus TAR. RESULTS: Baseline characteristics of the LIMA-RA-Y group (n = 346) compared with LIMA + SVG (n = 534) after PSM (n = 232 pairs) did not differ (3.3 ± 0.8 grafts per patient). Survival was worse for LIMA + SVG in the unmatched groups (KM, p < 0.001) and for PSM groups (KM, p = 0.043; Cox proportional hazards ratio: 1.3; 95% confidence interval: 1.0 to 1.6; p = 0.038). Survival did not differ between LIMA-RA-Y and other TAR (n = 5,800) patients before, or after, PSM (n = 332 pairs). CONCLUSIONS: Use of LIMA + SVG has worse survival than LIMA-RA-Y in achieving total arterial revascularization.

Local Hemodynamic Differences Between Commercially Available Y-Grafts and Traditional Fontan Baffles Under Simulated Exercise Conditions: Implications for Exercise Tolerance.

Fontan completion, resulting in a total cavopulmonary connection (TCPC), is accomplished using a lateral tunnel (LT), extracardiac conduit (ECC), or recently a bifurcated Y-graft. The local energetic differences between these graft types have not been substantially analyzed under exercise conditions. The present study evaluates the energetic performance of Y-grafts under simulated exercise conditions, compares their performance to the previous LT/ECC Fontan options, and discusses implications for exercise tolerance and hemodynamic predictability. Twenty Y-graft and 20 LT/ECC patients were analyzed. TCPC anatomies and flow waveforms were reconstructed using patient-specific cardiac magnetic resonance (CMR) images and phase-contrast CMR. Computational fluid dynamics simulations were performed to quantify indexed power loss (iPL) under both resting and simulated exercise conditions. Comparisons between graft types were investigated. iPL was significantly higher (p < 0.01) for Y-grafts at all activity levels. No significant interaction effects were observed between graft type and activity level. iPL at rest was strongly correlated (r 2 = 0.97, p < 0.001) with iPL at moderate exercise for Y-grafts, but less so for the LT/ECC cohort (r 2 = 0.66, p < 0.001). Similar results were seen for intense exercise, with a strong correlation for Y-grafts (r 2 = 0.94, p < 0.001) and a moderate correlation for LT/ECC (r 2 = 0.52, p < 0.001). Commercially available Y-grafts were found to have significantly higher iPL at all activity levels, suggesting worse exercise tolerance than the LT/ECC alternatives. Y-grafts offered impressive hemodynamic predictability which was not seen in the LT/ECC cohort. Our results encourage the further evaluation of an area-preserving Y-graft design to offer both improved energetic performance and hemodynamic predictability. Commercial Y-grafts show worse energetics, but more predictable responses than traditional Fontan connections under simulated exercise conditions. During simulated exercise conditions, commercially available Y-grafts show predictable but inferior energetic performance compared to lateral tunnel and extracardiac conduit Fontan connections, suggesting poorer exercise capacity. If Y-graft use is continued, these results encourage further evaluation of a cross sectional area-preserving Y-graft design as a additional alternative for Fontan completion.

Fontan Revision with Y-Graft in a Patient with Unilateral Pulmonary Arteriovenous Malformation.

The extracardiac conduit Fontan procedure is the last surgical step in the treatment of patients with a functional single ventricle. An acquired pulmonary arteriovenous malformation may appear perioperatively or postoperatively due to an uneven hepatic flow distribution. Here we report a case of a bifurcated Y-graft Fontan operation in a 15-year-old male patient with a unilateral pulmonary arteriovenous malformation after an extracardiac conduit Fontan operation.

Intra-Atrial Y-Graft Fontan for Univentricular Heart With Discontinuous Pulmonary Arteries.

The Y-graft Fontan as described today suffers from the disadvantage of being hostage to restrictions imposed upon the design of the limbs of the Y by existent cardiac anatomy. We describe a patient with discontinuous pulmonary arteries following a prior Glenn shunt, who underwent Fontan completion using an intra-atrial Y-limb placement for recruitment of the discontinuous pulmonary artery. Intracardiac placement of the limb(s) of the Y-graft could potentially increase the applicability of this Fontan modification without being constrained by external cardiac anatomy.

A pulsatile hemodynamic evaluation of the commercially available bifurcated Y-graft Fontan modification and comparison with the lateral tunnel and extracardiac conduits.

OBJECTIVE: Fontan completion, resulting in a total cavopulmonary connection, is accomplished using a lateral tunnel, extracardiac conduit, or bifurcated Y-graft. The use of Y-grafts is hypothesized to provide symmetric hepatic blood flow distribution to the lungs, a factor related to pulmonary arteriovenous malformations. The present study evaluates the hemodynamic performance of the largest commercially available Y-graft cohort to date, highlights 6 representative cases, and compares commercially available Y-graft performance with lateral tunnel/extracardiac conduit connections. METHODS: A total of 30 patients with commercially available Y-grafts and 30 patients with lateral tunnel/extracardiac conduits were analyzed. Total cavopulmonary connection anatomies and flow waveforms were reconstructed using cardiac magnetic resonance images and phase-contrast cardiac magnetic resonance. Computational fluid dynamic simulations were performed to quantify total cavopulmonary connection power loss, resistance, and hepatic flow distribution. Comparisons between graft types were investigated. RESULTS: Total cavopulmonary connection resistance was significantly higher for Y-grafts. Hepatic flow distribution was similar overall but showed discrepancies at extreme values with more unbalanced flow in the Y-graft cohort. Power loss was more sensitive to left pulmonary artery stenosis in the Y-graft cohort. Prediction of Y-graft hepatic flow distribution is multifactorial. CONCLUSIONS: Commercially available Y-grafts do not inherently provide more balanced hepatic flow distribution than lateral tunnel/extracardiac conduit connections, which are more energetically favorable and less sensitive to pulmonary artery stenosis. Graft type should be considered on an individual basis because hemodynamic performance is based on a combination of factors, including pulmonary flow distribution, pulmonary artery stenosis, and superior vena cava positioning.

Complete myocardial revascularization using only bilateral internal thoracic arteries provides a low-risk and durable 10-year clinical outcome.

OBJECTIVES: Bilateral internal thoracic artery (BITA) bypass provides long-term survival benefits over strategies that use single internal mammary arteries during coronary artery bypass grafting (CABG). However, the rate of adoption of this strategy remains very low. Moreover, optimal BITA configuration and the use of cardiopulmonary bypass still remain a matter of debate. We investigated the long-term results of a coronary revascularization strategy, utilising exclusively BITA-Y composite grafts using off-pump platform and sequential anastomoses. METHODS: From March 2000 to November 2010, all isolated CABGs (n = 2057 patients) were performed using an off-pump platform. Of these, 1240 patients had three-vessel coronary disease (60.3%), with severe coronary disease defined as >70% stenosis and three-vessel disease defined as the presence of 3 vessels with >70% stenosis, of which 784 (63.2%) were treated with two internal thoracic artery grafts in a composite fashion with a no-touch technique avoiding any manipulation of the ascending aorta. The primary end-point was the long-term survival and freedom from major adverse cerebral and cardiovascular events (MACCEs). The follow-up was completed using the annual anniversary method. RESULTS: The mean number of anastomoses per patient was 4.0. Hospital mortality occurred in 8 patients (1%). Ninety-day stroke, myocardial infarction and repeat revascularization rates were respectively 0.7, 0.6 and 0.3%. The mean follow-up was 6.6 ± 3.2 years and was obtained for 99% of the patients. The 5- and 10-year survival rates were 93.1 ± 1.6 and 83.8 ± 3.2%, respectively. Freedom from major adverse cardiac and cardiovascular event (MACCE) at 5 and 10 years was: cardiovascular event: 98.7 ± 1.6 and 96.1 ± 1.7%, documented ischaemia: 90.5 ± 2 and 80.2 ± 3.8%, revascularization: 94.0 ± 1.5 and 89.7 ± 2.5%, infarction: 98.1 ± 0.8 and 96.0 ± 1.6%. The patency of left and right internal thoracic artery in a BITA-Y configuration was 91.1 and 88.8% at 5 ± 3 years, respectively. CONCLUSION: Performance of an exclusive composite BITA off-pump revascularization strategy optimal and sustained long-term protection from MACCE.