High-frequency epicardial ultrasound: review of a multipurpose intraoperative tool for coronary surgery.

Background: In open-chest coronary artery bypass grafting (CABG), the surgeon faces several intraoperative challenges: (1) to locate the target coronary artery, (2) to select the optimal anastomotic site, and (3) to assess the quality of the graft and distal anastomosis. Endoscopically, these three diagnostic aims are particularly challenging.

Methods: We reviewed the literature on the intraoperative application of high-frequency (6.

Coronary connector devices: analysis of 1,469 anastomoses in 1,216 patients.

Automated coronary anastomotic devices could be the key to limited or port access procedures. To evaluate their clinical performance to date, 33 studies that included systematic elective angiographic imaging were reviewed, reporting on five proximal and seven distal devices. Marked outcome differences between the technologies were uncorrelated to study type and demographic, operative, and follow-up variables.

Cognitive outcomes five years after not undergoing coronary artery bypass graft surgery.

Background: Patients with coronary artery disease who underwent coronary artery bypass graft surgery have a high risk of cognitive decline 5 years after the procedure. It is conceivable that this is not caused by the operation, but by natural aging.

Methods: Psychologists repeatedly administered a battery of seven neuropsychological tests with eight main variables to 112 subjects without known coronary artery disease, with a time interval of 5 years.

Robot-assisted 13 MHz epicardial ultrasound for endoscopic quality assessment of coronary anastomoses.

In totally endoscopic coronary artery bypass surgery, intra-operative assessment of anastomotic quality is needed. We evaluated the endoscopic application of epicardial ultrasound to visualize the coronary anastomosis and detect a construction error. In 8 pigs (71-78kg), 16 internal mammary artery to left anterior descending coronary artery anastomoses were constructed conventionally, either correctly (n=8) or incorrectly with a suture cross-over construction error (n=8).

Cognitive and cardiac outcomes 5 years after off-pump vs on-pump coronary artery bypass graft surgery.

Context: Conventional coronary artery bypass graft surgery with use of cardiopulmonary bypass (on-pump CABG) is associated with excellent long-term cardiac outcomes but also with a high incidence of cognitive decline. The effect of avoiding cardiopulmonary bypass (off-pump CABG) on long-term cognitive and cardiac outcomes is unknown.

Objective: To compare the effect of off-pump CABG and on-pump CABG surgery on long-term cognitive and cardiac outcomes.

Cyclooxygenase-2 inhibition increases mortality, enhances left ventricular remodeling, and impairs systolic function after myocardial infarction in the pig.

Background: Cyclooxygenase (COX)-2 expression in the heart increases after myocardial infarction (MI). In murine models of MI, COX-2 inhibition preserves left ventricular dimensions and function. We studied the effect of selective COX-2 inhibition on left ventricular remodeling and function after MI in a pig model.

S2 connector versus suture: distal coronary anastomosis remodeling, patency, and function in the pig.

Background: Anastomotic connectors could be the key to less invasive bypass surgery, including endoscopic procedures, but equivalence to conventional suturing needs to be established. A novel distal coronary connector was tested pre-clinically for safety and efficacy in comparison to conventional suturing.

Methods And Results: Left internal thoracic to left anterior descending coronary artery bypasses were constructed off-pump in 35 pigs (73+/-8 kg).

Risk and determinants of myocardial injury during off-pump coronary artery bypass grafting.

Perioperative myocardial injury (PMI) after coronary revascularization (bypass surgery using cardiopulmonary bypass or percutaneous intervention) is strongly associated with future adverse events, such as death, myocardial infarction, and coronary intervention. The incidence, determinants, and prognostic significance of PMI after bypass surgery without cardiopulmonary bypass (off-pump surgery) are unknown. The study population comprised the patients who were randomized to off-pump surgery in the Octopus Study.

Ultrasound mini-transducer with malleable handle for coronary artery surgery.

Purpose: A 13 MHz epicardial ultrasound mini-transducer (15 x 9 x 6 mm) with a custom made malleable handling tool was evaluated to assess the coronary artery and anastomosis on all sides of the heart.

Description: On indication, in 8 patients undergoing coronary artery bypass surgery on the arrested heart, 8 coronary arteries as well as 27 coronary anastomoses were scanned.

Evaluation: The malleable handle was easily adjusted, and all sides of the heart were accessible for scanning with the mini-transducer.

Quality assessment of distal S(2)AS connector anastomosis by 13 MHz epicardial ultrasound.

Objective: During application of a distal coronary bypass connector, we employed 13 MHz epicardial ultrasound to evaluate quantitative caliper measurements for vessel size matching and to assess anastomosis quality after connector deployment.

Methods: Two S(2)AS connector anastomoses were constructed on ex vivo pressure-perfused porcine hearts. Epicardial ultrasound measurements of the connector ring and anastomosis were compared to intravascular ultrasound measurement and cast dimensions.

Transmural differences in myocardial function and metabolism during direct left ventricular to coronary artery sourcing.

Background: We investigated the hypothesis that in the absence of collateral circulation, a left ventricle-coronary artery (LV-CA) bypass will maintain normal LV wall function and metabolism transmurally, both at rest and during stress, when the left anterior descending coronary artery (LAD) is acutely occluded proximally.

Methods: In 18 anesthetized pigs (74 +/- 7 kg, mean +/- standard deviation), a covered stent was placed transmurally in the lateral wall of the beating LV and connected to the proximal LAD via an arterial graft. Subepicardial and subendocardial segmental shortening as well as interstitial lactate and glucose concentrations were measured regionally by sonomicrometry and microdialysis, respectively.

Detection of construction errors in ex vivo coronary artery anastomoses by 13-MHz epicardial ultrasonography.

Objective: Intraoperative detection of suboptimal coronary anastomoses allows revision before chest closure. We evaluated an epicardial 13-MHz ultrasound minitransducer as a means to detect three different coronary anastomosis construction errors.

Methods: In total, 120 internal thoracic artery-to-coronary artery anastomoses were constructed correctly (n = 60) or incorrectly (n = 60) with one technical error: suture crossover, purse-string or deep toe stitch (n = 20 each).

Role of coronary collaterals in off-pump and on-pump coronary bypass surgery.

Background: Collaterals limit infarct size, preserve viability, and reduce mortality in patients with acute myocardial infarction. In patients with stable coronary disease, collaterals are associated with less angina and ischemia during angioplasty and fewer ischemic events during follow-up. The role of collaterals has not been studied in patients undergoing off-pump or on-pump bypass surgery.

Activation of hemostasis after coronary artery bypass grafting with or without cardiopulmonary bypass.

Activation of coagulation, fibrinolysis, and the vascular endothelium occurs after heart surgery with cardiopulmonary bypass (CPB), but the effects of eliminating CPB in patients undergoing coronary artery bypass grafting (CABG) are unknown. Therefore, we compared the hemostatic profiles of off-pump and on-pump CABG patients. Two groups of consecutive patients participating in a larger trial (the Octopus Trial) were randomly allocated to undergo CABG with (n = 20) or without (n = 20) CPB.

Geometry assessment of coronary artery anastomoses with construction errors by epicardial ultrasound.

Objective: There is concern about the quality of the distal anastomosis in off-pump coronary artery bypass grafting. We investigated the impact of specific construction errors on anastomotic geometry using epicardial ultrasound.

Methods: Twelve ex vivo pressure perfused porcine and five isolated post-mortem human hearts were used to construct 35 internal mammary artery to coronary artery anastomoses, either without (n = 7) or with a standardized construction error (oversutured toe, oversutured heel, cross-over or purse string; each error, n = 7).

Ninety-degree anterior cardiac displacement in off-pump coronary artery bypass grafting: the Starfish cardiac positioner preserves stroke volume and arterial pressure.

Purpose: In off-pump coronary surgery through sternotomy, exposure of posterior circumflex branches causes circulatory deterioration in both patients and pigs. We assessed cardiac pump function when displacing the pig heart anteriorly with a suction cardiac positioner.

Description: Six pigs (+/-80 kg) underwent sternotomy for hemodynamic instrumentation using catheter-tipped manometers and paced at 80 beats/min.

Myocardial blood supply through a direct left ventricle-coronary artery shunt is not aided by augmented coronary capacitance.

Objectives: Left ventricle-coronary artery shunting is proposed as an alternative means of myocardial revascularization when standard methods are not an option. During diastole, however, regurgitant coronary flow to the left ventricle decreases the efficacy of the left ventricle-coronary artery shunt. We investigated whether augmented coronary compliance would improve net forward shunt flow.

Endoscopic localization and assessment of coronary arteries by 13 MHz epicardial ultrasound.

Background: In totally endoscopic coronary artery bypass grafting the target coronary artery is difficult to locate and assess. We explored the capacity of a high-frequency epicardial ultrasound mini-transducer (Aloka, Tokyo, Japan) to endoscopically locate and assess the left anterior descending (LAD), third obtuse marginal (OM3), and right posterior descending (RDP) coronary arteries.

Methods: In eight pigs, the LAD, OM3, and RDP were endoscopically exposed.

Stapled coronary anastomosis with minimal intraluminal artifact: The S2 Anastomotic System in the off-pump porcine model.

Objective: A reliable, easy-to-use, 1-shot anastomotic device will significantly push the barrier for less invasive coronary bypass surgery. The current study was designed to test the safety, efficacy, and early patency of a novel distal anastomotic device.

Methods: The S2 Anastomotic System (iiTech BV, Amsterdam, The Netherlands) was used in 10 consecutive pigs (73 kg) on a mild antiplatelet regimen.

Randomized comparison between stenting and off-pump bypass surgery in patients referred for angioplasty.

Background: Stenting improves cardiac outcome in comparison with balloon angioplasty. Compared with conventional surgery, off-pump bypass surgery on the beating heart without cardiopulmonary bypass may reduce morbidity, hospital stay, and costs. The purpose, therefore, was to compare cardiac outcome, quality of life, and cost-effectiveness 1 year after stenting and after off-pump surgery.

Endoscopic exposure and stabilization of posterior and inferior branches using the endo-starfish cardiac positioner and the endo-octopus stabilizer for closed-chest beating heart multivessel CABG: hemodynamic changes in the pig.

Background: Closed-chest, off-pump, multivessel CABG requires modified instruments to expose and stabilize posterior and inferior coronary branches. Using three new prototype devices, we explored the feasibility of endoscopic bypass grafting on these branches and assessed cardiac function during cardiac displacement.

Methods: Eight pigs (75 to 85 kg) were instrumented for hemodynamics and paced at 80 to 100 bpm.

Permanent wall stretching in porcine coronary and internal mammary arteries.

Background: Anastomotic connectors may induce substantial arterial wall deformation and, hence, wall injury. We studied arterial wall damage and repair after sustained large longitudinal elongation in the porcine coronary and internal mammary arteries in vivo.

Methods: A stretch device that elongates a part of the artery by 80% was implanted in 8 pigs.

Coronary anastomotic devices: blood-exposed non-intimal surface and coronary wall stress.

Objective: This study compares the area of blood-exposed non-intimal surface in device-constructed anastomoses with the conventionally sutured anastomosis and examines the technical feasibility of 0 blood-exposed non-intimal surface anastomosis configurations.

Methods: In the device-constructed anastomosis, blood-exposed non-intimal surface was estimated in all anastomosis configurations identified in truly new (ie, nonduplicate and nonrelated) patent applications and in anastomotic devices recently introduced by several institutions. In the sutured anastomosis, blood-exposed non-intimal surface area was estimated by analysis of previously investigated anastomoses.

Mechanical properties of porcine and human arteries: implications for coronary anastomotic connectors.

Background: To determine whether the pig is an appropriate experimental animal for studies on distal anastomotic connectors in coronary artery bypass surgery, the mechanical properties of young porcine and old human coronary and internal mammary arteries were compared within and beyond the physiologic range of strains.

Methods: Coronary arteries from 6 humans and 8 pigs were studied as well as internal mammary arteries of 3 humans and 6 pigs (human, aged 61 to 85 years; pig, 78.7 +/- 5.

Briefly occlusive coronary anastomosis with tissue adhesive.

Objective: We assessed the feasibility of a facilitated, briefly occlusive, sutureless coronary anastomosis technique in which side-to-side preglued (octylcyanoacrylate adhesive) bounded walls were opened by a conventional arteriotomy.

Methods: In low-flow (prothrombotic milieu, View Article and Find Full Text PDF