Comparing Mortality of RoboticAssisted Coronary Artery Bypass Grafting

Comparing Mortality of Robotic-Assisted Coronary Artery Bypass Grafting with Conventional Surgery in Coronary Artery Disease Patients Ryan A. Ule, MPH, MMS (c) Faculty Advisor: Zachary Weik, MHS, PA-C Department of Medical Science Abstract Results Discussion Coronary artery disease (CAD) is the most common heart disease in the U. S, often leading to complications such as myocardial infarction and death. Coronary artery bypass grafting (CABG) is the preferred surgical treatment to extend the lives of stable CAD patients with multi-vessel disease. Although conventional, open CABG (C-CABG) remains the surgical treatment of choice, less invasive techniques exist, such as robotic -assisted CABG (R-CABG). Little is known about the mortality comparisons between the two techniques. This paper explores: In the surgical treatment of coronary artery disease in adult patients (P), do robotic-assisted surgical techniques (I) result in less overall mortality (O) compared to conventional bypass grafting surgery (C)? One study found that while robotic-assisted techniques were safe, it did not significantly decrease cardiovascular events or mortality in CAD patients (Wu et al, 2019). Another study concluded that while there were lower rates of major perioperative complications for R-CABG, there was no significant difference in mortality compared to standard of care CABG (Whellan et al, 2016). Overall, only one study demonstrated statistically significant evidence that robotically-assisted technique results in an overall decrease in mortality (Su et al, 2018). Still, each study was limited by factors such as selection bias. The evidence from this analysis demonstrated that R-CABG was comparable to conventional surgical techniques in regard to safety and efficacy. However, the evidence was not convincing enough to conclude that R-CABG surgical techniques resulted in less overall mortality in clinical practice. • A majority of the studies found that mortality outcomes for R-CABG was comparable or slightly superior to C-CABG. • Just one study had data that was statistically significant in favor of RCABG both perioperative mortality and long-term survival at 1, 5, or 10 years robotic-assisted CABG had lower rates of in-hospital and long-term mortality than both conventional CABG and PCI procedures. • Most studies had stringent inclusion criteria to ensure appropriate subjects, while using propensity matching to reduce confounding variables among participants. • However, not all studies measured long-term mortality. All studies had limitations such as cohort, observational study designs, unmatched groups, and selection bias. Introduction Table 1. Comparison of study designs for Robotic-Assisted Surgical Techniques vs. Standard Coronary Artery Disease (CAD) Overview: Symptoms: Surgical Treatment: • CAD is the most • Most common: 1. PCI: 1 or 2 vessel common of the Angina - LVF nearly normal cardiovascular • Onset of CAD often is - Does not involve Left diseases, most preceded by a main coronary artery commonly caused by myocardial infarction 2. CABG: 3+ vessel atherosclerosis • MI symptoms may - LVF <40%; stenosis • 18. 2 million U. S. include shortness of >70% adults currently breath, weakness, - Involves Left main diagnosed nausea, pain in arm or coronary artery • Mortality of 365, 914 shoulder, jaw pain • Conventional & in 2017 in the U. S. Robotic Methods • A literature review was conducted using Pub. Med and EBSCOhost in November 2019. Five articles were selected for critical appraisal based on pertinency to the PICO question, surgical techniques used, study design, and outcomes measured. • Exclusion Criteria: - Studies that investigated other surgical settings with robotic use - Studies that did not investigate efficacy, safety and overall survival - Studies using overlapping statin therapy - Meta-analyses & periodicals • Inclusion Criteria: - Studies comparing conventional CABG surgery and robotic CABG surgery alone Study Design Su et al (2018) (1) RC Walters et al (2018) (2) Cohort Whellan et al (2016) (3) RC Total (N) Procedures/Cases Involved Outcome Measurements N = 472: 139 R-CABG 147 C-CABG 186 PCI Patients with proven LM disease >50%; da Vinci robot system TVR, long-term survival, All-causedeath, ICU LOS, total hospital stay N = 313: 103 Robotic 210 Non- Robotic Unknown MACE - any death, stroke, myocardial infarction, TVR N = 127, 717 (2006) isolated CABG N = 97, 249 (2012) operations involving a left interior mammary artery (LIMA) Post-op LOS, and post-op complications, operative and discharge mortality Operation time, inhospital CV and renal events, allcause death Wu et al (2019) (4) RC N = 44: 22 Robotic 22 Non-robotic BIMA grafting through the left pleural space - da Vinci robot system; sternotomy CABG Yanagawa et al (2015) (5) RC N = 15, 530: 5, 199 Robotic 10, 331 Non-robotic Valves or septa, Median cost, overall vessels, pericardium mortality, LOS, procedures complications for all operation types Key: R‐CABG = robotic‐assisted coronary artery bypass grafting; C‐CABG = conventional coronary artery bypass grafting; LM = Left main (coronary artery disease); LIMA = left internal mammary artery; BIMA = bilateral internal mammary artery; LAD = anterior descending artery; MACE = Major adverse cardiovascular events; MACCE = major adverse cardiac and cerebral events; TVR = target vessel revascularization; ICU = intensive care unit; LOS = length of stay; M= male; F= Female; RC= Retrospective Cohort Table 2. Comparison of results: Robotic-Assisted Surgical Techniques vs. Conventional Bypass Grafting Surgery Study 1 2 3 4 5 Perioperative Mortality Long-term Survival TVR MACE Length of Stay S NS NS NA NA NS NS NS S NA NA S NS S S NA S NS S Key: S = statistically significant (p < 0. 05); NS = not statistically significant (p > 0. 05); NA = No results Available MACE = Major Adverse Cardiovascular Events = Stroke, MI, heart failure; Perioperative mortality = death within 30 days of procedure; Long‐term survival = all‐cause death at 1, 5, or 10 years; Length of stay = ICU or total hospital stay ; TVR = Target Vessel Revascularization Conclusion The expansion of R-CABG for CAD patients shows promise, as its use has been found to be safe, effective, and comparable to C-CABG outcomes. While some statistical significance has been found in its favor over conventional techniques, it can not be determined that robotic CABG resulted in significantly less overall mortality than standard CABG. Future studies should look to improve the validity of these findings through randomized trials which matched study groups that better assess lifelong mortality. However, these studies did conclude promising findings to suggest that robotic surgery is a safe and cost-effective alternative technique for performing cardiac surgery and provides enough evidence to encourage future research about the overall mortality on conventional vs robotic CABG patients. Given these findings, more data is needed to accurately distinguish a preference for R-CABG in clinical practice. References 1. Wu C‐J, Chen H‐H, Cheng P‐W, et al. Outcome of Robot‐Assisted Bilateral Internal Mammary Artery Grafting via Left Pleura in Coronary Bypass Surgery. Journal of Clinical Medicine. 2019; 8(4): 502. doi: 10. 3390/jcm 8040502. 2. Su C‐S, Chen Y‐W, Shen C‐H, et al. Clinical outcomes of left main coronary artery disease patients undergoing three different revascularization approaches. Medicine. 2018; 97(7). doi: 10. 1097/md. 0000009778. 3. Whellan DJ, Mccarey MM, Taylor BS, et al. Trends in robotic‐assisted coronary artery bypass Grafts: A study of the society of thoracic surgeons adult cardiac surgery database, 2006 to 2012. The Annals of Thoracic Surgery. 2016; 102(1): 140‐ 146. doi: 10. 1016/j. athoracsur. 2015. 12. 059. 4. Walters D, Reeves RR, Patel M, Naghi J, Ang L, Mahmud E. Complex robotic compared to manual coronary interventions: 6‐ and 12‐month outcomes. Catheterization and Cardiovascular Interventions. 2018; 93(4): 613‐ 617. doi: 10. 1002/ccd. 27867 5. Yanagawa F, Perez M, Bell T, et al. Critical Outcomes in Nonrobotic vs Robotic‐Assisted Cardiac Surgery. JAMA Surgery. 2015; 150(8): 771. doi: 10. 1001/jamasurg. 2015. 1098.