A prospective, single-center, randomized study to assess whether automated coregistration of optical coherence tomography with angiography can reduce geographic miss.

OBJECTIVE: We sought to evaluate whether automated coregistration of optical coherence tomography (OCT) with angiography reduces geographic miss (GM) during coronary stenting. BACKGROUND: Previous intravascular ultrasound or OCT studies have showed that residual disease at the stent edge or stent edge dissection was associated with stent thrombosis or edge restenosis. This has been termed GM. METHODS: Two hundred de novo coronary lesions were randomized in a 1:1 ratio to OCT-guided percutaneous coronary intervention (PCI) with versus without automated coregistration of OCT with angiography. GM, the primary endpoint, was defined as angiographic ≥type B dissection or diameter stenosis >50% or OCT minimum lumen area <4.0 mm2 with significant residual disease or dissection (dissection flap >60°) within 5 mm from the stent edge. RESULTS: The prevalence of GM was not different comparing OCT-guided PCI with versus without automated coregistration (27.6% vs 34.0%, P = 0.33). However, there was a trend toward a reduced prevalence of significant distal stent edge dissection in lesions with automated coregistration (11.1% vs 20.8%, P = 0.07). The discrepancy in the distance between planned versus actual implanted stent location with automated coregistration was significantly shorter than without coregistration (1.9 ± 1.6 mm vs 2.6 ± 2.7 mm, P = 0.03), especially the prevalence of ≥5 mm discrepancy that was less frequent with automated coregistration. CONCLUSIONS: Automated coregistration of OCT with angiography did not reduce the primary endpoint of GM after stent implantation.

Forging a sustainable sky: Unveiling the pillars of aviation e-fuel production for carbon emission circularity.

In 2021, airplanes consumed nearly 250 million tons of fuel, equivalent to almost 10.75 exajoules. Anticipated growth in air travel suggests increasing fuel consumption. In January 2022, demand surged by 82.3%, as per the International Air Transport Association. In tackling aviation emissions, governments promote synthetic e-fuels to cut carbon. Sustainable aviation fuel (SAF) production increased from 1.9 million to 15.8 million gallons in six years. Although cost of kerosene produced with carbon dioxide from direct air capture (DAC) is several times higher than the cost of conventional jet fuel, its projected production cost is expected to decrease from $104-$124/MWh in 2030 to $60-$69/MWh in 2050. Advances in DAC technology, decreasing cost of renewable electricity, and improvements in FT technology are reasons to believe that the cost of e-kerosene will decline. This review describes major e-kerosene synthesis methods, incorporating DAC, hydrogen from water electrolysis, and hydrocarbon synthesis via the Fischer-Tropsch process. The importance of integrating e-fuel production with renewable energy sources and sustainable feedstock utilization cannot be overstated in achieving carbon emission circularity. The paper explores the concept of power-to-liquid (PtL) pathways, where renewable energy is used to convert renewable feedstocks into e-fuels. In addition to these technological improvements, carbon pricing, government subsidies, and public procurement are several policy initiatives that could help to reduce the cost of e-kerosene. Our review provides a comprehensive guide to the production pathways, technological advancements, and carbon emission circularity aspects of aviation e-fuels. It will provide a valuable resource for researchers, policymakers, industry stakeholders, and the general public interested in transitioning to a sustainable aviation industry.

Defining the learning curve for robotic-assisted endoscopic harvesting of the left internal mammary artery.

OBJECTIVE: Robotic-assisted techniques are continuing to cement their role in coronary surgery, particularly in facilitating the endoscopic harvesting of the left internal mammary artery (LIMA), regardless of how the subsequent bypass grafting is performed. As more surgeons attempt to become trained in robotic-assisted procedures, we sought to better define the learning curve associated with robotic-assisted endoscopic LIMA harvest. METHODS: Between January 2011 and July 2012, a total of 77 patients underwent robotic-assisted minimally invasive direct coronary artery bypass surgery at our institution. The LIMA was harvested endoscopically in all patients, using standard robotic instruments, followed by direct grafting to anterior wall myocardial vessels via a small thoracotomy. Intraoperative times for various components of the procedure were collated and analyzed. RESULTS: The mean ± SD time taken to insert and position the ports for the robotic instruments was 3.9 ± 1.4 minutes. The mean ± SD LIMA harvest time was 31.8 ± 10.1 minutes, and the mean ± SD total robotic time was 44.2 ± 12.9 minutes. All time variables consistently continued to decrease as the experience of the operating surgeon increased, with the greatest magnitude of improvement being evident within the first 20 cases. The logarithmic learning curves for LIMA harvest time and total robot time during our entire experience were both calculated as 90%, correlating to an expected 10% improvement in performance for each doubling of cases completed. CONCLUSIONS: Coronary surgeons can rapidly become proficient in robotic-assisted endoscopic LIMA harvest, with significant improvement in operative times evident within the first 20 cases completed. These data may be useful in designing appropriate training programs for newer surgeons seeking to gain experience in robotic-assisted coronary surgery.

Does dual antiplatelet therapy affect blood loss and transfusion requirements in robotic-assisted coronary artery surgery?

OBJECTIVE: Patients who present for coronary surgery often receive preoperative dual antiplatelet therapy with aspirin and a thienopyridine derivative (clopidogrel or prasugrel), especially after a recent acute coronary syndrome. Studies have shown that patients on aspirin and clopidogrel are at increased risk for perioperative bleeding and related events. We sought to examine the impact of dual antiplatelet therapy on bleeding and transfusion requirements in patients undergoing robotic-assisted minimally invasive coronary artery bypass grafting. METHODS: From January 2010 to November 2011, a total of 110 patients underwent robotic-assisted off-pump coronary surgery at our institution. All patients underwent robotic-assisted harvest of the left internal mammary artery from the chest wall. Some patients then underwent direct coronary anastomosis to the left anterior descending coronary artery via a left minithoracotomy, whereas others had a complete robotic endoscopic procedure within the closed chest. The patients were divided into two groups for outcome analysis on the basis of preoperative antiplatelet therapy: group 1 (either aspirin alone or no antiplatelet agents at all; n = 53) and group 2 (aspirin plus clopidogrel or prasugrel; n = 57). RESULTS: Perioperative chest tube drainage was not significantly different between the patient groups, irrespective of the preoperative antiplatelet agents used. Transfusion requirements and other morbidities were also similar in both groups of patients. CONCLUSIONS: Preoperative dual antiplatelet therapy does not result in significantly increased bleeding or perioperative transfusion requirements. If clinically indicated, it is reasonable to continue preoperative combination antiplatelet therapy in patients undergoing robotic-assisted coronary surgery.

Does body mass index affect outcomes in robotic-assisted coronary artery bypass procedures?

OBJECTIVE: Obese patients pose unique technical challenges for minimal-access cardiac surgery. We sought to examine the effect of body mass index on short-term outcomes in robotic-assisted coronary surgery. METHODS: From January 2010 to November 2011, a total of 110 consecutive patients underwent robotic-assisted coronary surgery at our institution. All patients had robotic-assisted mobilization of the left internal mammary artery. Some patients then underwent direct coronary anastomosis to the left anterior descending coronary artery via a left mini thoracotomy, whereas others had a complete robotic endoscopic procedure within the closed chest. The short-term outcomes of obese patients (n = 39), defined as body mass index greater than 30 kg/m, were compared with those of nonobese patients (n = 71). RESULTS: Mean left internal mammary artery harvest time was longer in obese patients than in nonobese patients (51.03 vs 39.94 minutes; P = 0.007), as was overall operative time (218.15 vs 186.72 minutes; P = 0.034). There were no significant differences in mortality or major morbidity between obese and nonobese patients. CONCLUSIONS: Obesity does not adversely affect short-term outcomes in robotic-assisted coronary surgery, although operative times are somewhat longer for these patients. Robotic-assisted coronary techniques can be safely pursued in obese patients.

Minimally invasive direct coronary artery bypass as a primary strategy for reoperative myocardial revascularization.

OBJECTIVE: : Conventional reoperative coronary artery bypass grafting is associated with risk of sternal re-entry, injury to patent grafts, and embolization from diseased grafts. Sternal sparing minimally invasive direct coronary artery bypass (MIDCAB) avoids such risks in cases where it is technically feasible. We sought to examine in-hospital outcomes of reoperative MIDCAB surgery. METHODS: : We recorded prospective standardized data from the New York Cardiac Surgical Reporting System database of 369 reoperative MIDCAB cases from 1996 to 2006 and compared with 822 primary MIDCAB patients in the same time period. We compared the preoperative risk profile and postoperative in-hospital outcomes and length of stay for both groups. RESULTS: : There was a significantly higher risk profile typical of the reoperative patient population (P < 0.001 for stroke, peripheral/cerebrovascular disease, extensive aortic calcification, renal failure, and left ventricular ejection fraction <40%) compared with the primary MIDCAB group. Despite this fact, there was no difference in the in-hospital outcomes and length of hospital stay between the two groups. CONCLUSIONS: : Reoperative MIDCAB provides targeted coronary revascularization and avoids hazards of sternal re-entry, graft injury and manipulation, and deleterious effects of cardiopulmonary bypass. This hastens recovery and provides excellent early outcomes equivalent to primary MIDCAB procedures.

Off-pump Coronary Bypass Surgery in Patients With Low Ejection Fraction: Is There a Long-Term Survival Advantage?

OBJECTIVE: : Long-term survival after off-pump surgery in patients with low ejection fraction was investigated. METHODS: : Three hundred forty-six patients with ejection fraction 30% or less with isolated off-pump coronary artery bypass surgery (OPCAB) were compared with a propensity matched historical group operated on-pump (ONCAB) and with data from literature after percutaneous coronary intervention and OPCAB surgery. RESULTS: : The lower invasiveness of OPCAB contributed to a significantly better 30-day survival, shorter postoperative length of stay, and fewer in-hospital complications. Incomplete revascularization of the posterior and lateral territories of the heart correlated with higher 1-year mortality. The probability of survival for 8 years after OPCAB was 50.1% (n = 76) versus 49.7% (n = 82) for ONCAB without comparable data from literature for OPCAB or percutaneous coronary intervention in these high-risk patients. CONCLUSIONS: : OPCAB surgery in patients with low ejection fraction is a viable alternative but so far without demonstrable long-term survival advantage to ONCAB.

Long-Term Survival After Minimal Invasive Direct Coronary Artery Bypass (MIDCAB) Surgery in Patients With Low Ejection Fraction.

OBJECTIVE: : The long-term survival after minimal invasive direct coronary artery bypass (MIDCAB) surgery to any coronary territory in patients with ejection fraction of ≤30% was investigated for the first time in literature. METHODS: : Seventy-three patients with primary MIDCAB and 89 patients with reoperative MIDCAB were studied including preoperative risk factors, operative details, early postoperative complications, and survival up to 10 years postoperatively. RESULTS: : Despite the high-risk profile of the patients, the MIDCAB approach for targeted revascularization resulted in excellent short-term results. Ventricular arrhythmia contributed to four of six early deaths. Survival at 5 years postoperatively was 62.5% for primary MIDCAB and 43.2% for reoperative MIDCAB and at 10 years was 36.9% and 29.5%, respectively. Functionally complete vascularization correlates with significantly better long-term survival particularly in primary MIDCAB procedures. CONCLUSIONS: : MIDCAB is a valuable option for targeted revascularization in high-risk patients with low ejection fraction and reoperation.

Less invasive intracardiac surgery performed without aortic clamping.

BACKGROUND: Aortic clamping and cardioplegia delivery add complexity to performing intracardiac procedures through a right minithoracotomy. Recent publications have shown excellent patient outcomes after mitral valve (MV) procedures undertaken through thoracotomy on the fibrillating heart. We reviewed our experience with this approach. METHODS: From March 2000 to September 2006, 100 patients underwent MV repair (n = 42), MV annuloplasty (n = 28), MV replacement (n = 18), atrial septal defect closure (n = 10), tricuspid valve repair (n = 1), and left atrial myxoma excision (n = 1). A modified maze procedure (n = 4) or left minimally invasive direct coronary bypass grafting (MIDCABG) (n = 2) was combined in six cases. The mean age was 57 +/- 11 years (range, 22 to 89); 27 patients were in New York Heart Association (NYHA) class III or IV; 24 cases were first or second time reoperations; 20 patients had a left ventricular ejection fraction of less than 0.3. All the operations were carried out on the fibrillating heart without cross-clamping the aorta through a right minithoracotomy using peripheral cannulation. RESULTS: Mean fibrillation time was 73 +/- 31 minutes (range, 10 to 198 minutes). There was no conversion to sternotomy. Postoperative inotropic support was needed in 20 cases. One patient who underwent a third time reoperation died within 30 days of mesenteric ischemia (hospital mortality = 1%). Complications were the following: four reoperations for bleeding (4%); two strokes (2%). Postoperative median hospital length of stay was five days (range, 2 to 58 days). None of the patients has required MV reoperation after hospital discharge. Follow-up was complete. All survivors were in NYHA class I or II. CONCLUSIONS: Ventricular fibrillation simplifies less invasive intracardiac procedures and carries lower complication rates and perioperative mortality compared with conventional surgery.