Minimally Invasive Direct Coronary Artery Bypass: An Evolving Paradigm Over the Past 25 Years

OBJECTIVE

We have routinely utilized minimally invasive direct coronary artery bypass (MIDCAB) for revascularization of the left anterior descending (LAD) coronary artery. We examined how this procedure has evolved.

METHODS

A retrospective review was undertaken of 2,283 consecutive patients who underwent MIDCAB between 1997 and 2021. Patients were divided into 3 groups: group A from 1997 to 2002 (n = 751, 32.9%), group B from 2003 to 2009 (n = 452, 19.8%), and group C from 2009 to 2021 (n = 1,080, 47.3%). Risk profiles and short-term outcomes were analyzed for the entire cohort and for 293 propensity-matched patients drawn from each group.

RESULTS

The left internal mammary artery was harvested open in group A but with robotic assistance in group C. Thirty-day mortality was higher in group A versus group C (12 deaths, 1.6% vs 5 deaths, 0.5%, P = 0.044); this difference was negated after propensity matching. Group A had more comorbidities than group C, including peripheral vascular disease (17.7% vs 10.0%, P < 0.001), congestive heart failure (39.6% vs 18.0%, P < 0.001), and a history of stroke (17.9% vs 10.0%, P < 0.001), although diabetes mellitus was more common in group C (51.4% vs 31.0%, P < 0.001). Stroke was greater in group A (1.2% vs 0.0% vs 0.2%, respectively, P = 0.004), as was the need for prolonged ventilation (3.6% vs 0.2% vs 0.9%, respectively, P < 0.001), before and after propensity matching.

CONCLUSIONS

MIDCAB patients had less comorbidities than in the past. Robot-assisted MIDCAB was associated with lower stroke risk.

Hybrid Minimally Invasive Approach for Combined Obstructive Coronary Artery Disease and Severe Aortic Stenosis

OBJECTIVE

There is a high prevalence of concomitant coronary artery disease (CAD) and aortic stenosis (AS), and these conditions can be treated with a variety of invasive and/or percutaneous approaches. The aim of this study is to demonstrate the feasibility, efficacy, and safety of a staged transcatheter aortic valve replacement (TAVR) after a hybrid minimally invasive direct coronary artery bypass surgery (MIDCAB) to treat combined complex CAD and AS.

METHODS

Six patients with concomitant CAD and severe AS underwent staged treatment of their CAD with MIDCAB and TAVR. All patients had significant complex left main or left anterior descending artery (LAD) stenosis deemed to be not amenable to percutaneous coronary intervention (PCI).

RESULTS

The average syntax score was 22±8 and the Society of Thoracic Surgeons score for surgical AVR was 8±3%. All patients underwent a single vessel MIDCAB for revascularization of the LAD (three patients required additional PCI for non-LAD disease). Two patients had pre-TAVR balloon aortic valvuloplasty and one patient also required treatment of severe mitral valve regurgitation with percutaneous edge-to-edge repair (the MitraClip). There was no intraprocedural or hospital mortality. No neurological deficits or vascular complications were recorded.

CONCLUSIONS

A hybrid staged approach for combined complex CAD and severe AS with MIDCAB, PCI, and TAVR is a valid option in high-risk patients. The order and timing of these procedures must be tailored to the patient's clinical symptoms, stability, and severity of disease.

Safety of Continued Clopidogrel Use in the Preoperative Course of Gastrointestinal Surgery: A Retrospective Cohort Study

OBJECTIVE

Our study aimed to estimate postoperative bleeding risk in older adults taking clopidogrel before gastrointestinal (GI) surgery, to aid surgeons in decisions regarding clopigogrel cessation.

SUMMARY BACKGROUND DATA

Balancing risks of postoperative bleeding associated with continued clopidogrel use and those associated with cessation is difficult for GI surgeons.

METHODS

Using 100% Texas Medicare Claims Data from 2006 to 2011, we identified patients undergoing emergent GI surgery. We propensity score matched patients on clopidogrel before surgery to patients not on clopidogrel. Using conditional logistic regression, we compared risks of bleeding events at 1-month postdischarge between groups, adjusting for bleeding risk factors.

RESULTS

In total, 1240 patients undergoing emergent GI surgery while treated with clopidogrel were matched to emergency GI surgery patients not treated with clopidogrel. The only significant preoperative differences between groups were higher percent of clopidogrel-treated patients with congestive heart failure, cholecystectomy, and lower percent of clopidogrel-treated patients with colectomy. Mean age was 76.91 (±7.06) and 76.70 (±7.05) years (P = 0.47), and 63.84% and 59.41% of operations were cholecystectomy, in the clopidogrel and nonclopidogrel groups (P = 0.18). In multivariable analyses adjusting for Elixhauser index, hyperlipidemia, confounding drugs, and surgery type, odds ratio for bleeding within 30 days of discharge in those exposed to clopidogrel compared with those not exposed was 1.60 (95% confidence interval, 1.08-2.38), with raw rates of bleeding 6.85% and 4.84%.

CONCLUSIONS

Clopidogrel use in older adults through the preoperative period of GI surgery does not significantly increase bleeding events in the month after surgery.

Evaluating Blood Loss and the Effect of Antiplatelet Treatment in Foot and Ankle Amputations

The interrelationship between diabetes mellitus and cardiovascular disease is well-documented, and, secondary to the latter, is the use of antiplatelet therapy. Although diabetes and the associated vascular manifestations are driving forces behind lower extremity amputations, few data are available on the risks of perioperative antiplatelet therapy with foot and ankle amputations. The goal of the present study was to address the surgical effect of continuing or discontinuing antiplatelet therapy before foot and/or ankle amputation. The following data were retrospectively collected: blood loss, pre- and postoperative hematocrit and hemoglobin, operative time, amputation type, age, diabetic status, antiplatelet treatment, and number of transfusions during the perioperative period. Perioperative antiplatelet therapy was defined as exposure to aspirin or clopidogrel within 3 days before surgery. To compare the outcomes between groups, the following factors were analyzed using bivariate analyses and then multivariate regression models: (1) the need for transfusions, (2) high blood loss (>20 mL), (3) volume of blood loss, and (4) operative time. The noninferiority of continued antiplatelet use was assessed in terms of operative time and blood loss, using a noninferiority margin of 10 minutes or 10 mL, respectively. Antiplatelet therapy was not a statistically significant risk factor for any of the studied outcomes on multivariate analysis. Equivalence testing revealed that continuing antiplatelet therapy is not inferior to discontinuing perioperative therapy in terms of blood loss and operative time. Multivariate analysis of the data suggested that antiplatelet therapy has no statistically significant impact on blood loss, transfusion rate, or operative time.

The impact of clopidogrel therapy on postoperative bleeding after robotic-assisted coronary artery bypass surgery

OBJECTIVES

The purpose of this study was to determine whether patients undergoing robotic-assisted coronary artery bypass graft surgery (CABG) on clopidogrel had an increased risk of bleeding complications compared with those not on clopidogrel.

METHODS

From 2008 to 2011, 322 patients underwent robotic-assisted CABG either as an isolated procedure or as part of a hybrid coronary revascularization procedure (HCR). Patients were classified according to whether they received clopidogrel within 5 days of surgery or intraoperatively (n = 64) compared with those who never received or who had discontinued clopidogrel therapy >5 days before surgery (n = 258). A propensity analysis using 31 preoperative variables was used to control for confounding variables. In a subgroup analysis, patients undergoing one-stage HCR (clopidogrel load 600 mg in odds ratio (OR) prior to stenting) were compared with patients in the clopidogrel group who underwent two-stage HCR.

RESULTS

In the Clopidogrel group, the mean interval between surgery and last dose of clopidogrel was 2.1 ± 1.5 days. Compared with the No Clopidogrel group, the Clopidogrel group had greater 24-h chest tube drainage (1003 ± 572 vs 782 ± 530 ml, P = 0.004) and more blood transfusions (35.9%, 23 of 64 patients vs 20.9%, 54 of 258 patients, P = 0.01). On logistic regression analysis, there was greater 24-h chest tube drainage in the Clopidogrel group (+198 ml, P = 0.02) and a significantly higher incidence of blood transfusion (OR = 2.30, P = 0.01). In the subgroup analysis, patients undergoing one-stage HCR (n = 17) had greater 24-h chest tube drainage compared with patients undergoing two-stage HCR (1262 vs 909 ml, P = 0.03).

CONCLUSIONS

Patients undergoing robotic-assisted CABG on clopidogrel had more postoperative bleeding and a higher incidence of blood transfusion. Therefore, despite a less invasive approach, surgery should be delayed in these patients when possible.

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.