Gabriela R. Dincheva

Arterial Grafts Protect the Native Coronary Vessels From Atherosclerotic Disease Progression

BACKGROUND We sought to examine the effect of different conduits on the progression of atherosclerosis in previously revascularized coronary territories. METHODS Between 1995 and 2010, 4,960 patients were discharged alive after primary isolated coronary artery bypass grafting (CABG) with a left internal thoracic artery (LITA) conduit and additional conduits as needed: radial artery (RA) or saphenous vein graft (SVG), or both. Seven hundred seventy-two patients had coronary angiography for recurrent symptoms an average of 5.5±3.5 years after CABG (range, 0.1-16 years). Cumulative graft patency and disease progression in the native vessels was estimated by the Kaplan-Meier survival method. The log-rank test was used to assess differences of disease progression per territory between different types of conduits. RESULTS Kaplan-Meier-estimated 1-, 5-, and 10-year overall disease progression in territories with patent LITAs was 0.01%, 4%, and 8%, respectively; with patent RA grafts, it was 0.01%, 6%, and 11%, respectively (log-rank test, p=0.157); and with patent SVGs it was 3%, 19%, and 43%, respectively (log-rank test; p<0.0001). Disease progression in grafted native coronary arteries in the anterior territory with patent LITA-to-left anterior descending (LAD) artery was 8%, and with patent RA grafts versus patent SVGs to the diagonal branches of LAD artery was 10% and 40%, respectively (log-rank test; p<0.0001). Disease progression in grafted native coronary arteries to the lateral territory with a patent RA graft was 11% versus 50% with a patent SVG (log-rank test; p<0.0001). CONCLUSIONS RA and LITA grafting has a strong protective effect against progression of native coronary artery disease in previously grafted vessels. Multiple arterial grafting may improve long-term survival by preventing progression of atherosclerosis in the native coronary vessels.

Multiple arterial bypass grafting should be routine

OBJECTIVE We sought to estimate the reduction in deaths and the number of additional person-years of life that could potentially be gained by nationwide adoption of routine multiple arterial bypass grafting (MABG). METHODS Propensity matching on 4883 patients undergoing primary, isolated coronary artery bypass grafting (CABG) using the left internal thoracic artery (LITA) from January 1995 to June 2011, resulted in 1023 matched pairs of LITA-radial artery and LITA-saphenous vein patients. Kaplan-Meier estimated survivals were used to calculate the potential number of lives that could be saved based on a 20% and an 80% rate of MABG, compared with the national 10% rate, when applied to a hypothetical national sample of 200,000 similar patients. RESULTS Our overall MABG rate was 40% with >80% rate for the past 3 years. Kaplan-Meier estimated 10-year survival was better for LITA-radial artery patients (83.1%) compared with LITA-saphenous vein patients (75.7%) (log rank test, P < .001). When compared with the current national 10% MABG rate, a 20% and an 80% MABG rate could potentially result in 1400 and 10,000 fewer annual deaths, respectively, among a hypothetical national cohort, yielding >9000 and >64,000 person-years of life over a 10-year period. CONCLUSIONS An 80% rate of MABG has the potential to prevent more than 10,000 deaths annually and add >64,000 person-years of life over the course of 10 years. The use of a second arterial graft during CABG should be routine in the majority of patients undergoing CABG.

Optimal Conduit for Diabetic Patients: Propensity Analysis of Radial and Right Internal Thoracic Arteries

BACKGROUND Multiple arterial grafts, in addition to the left internal thoracic artery, improve long-term survival after coronary artery bypass grafting (CABG); yet, the use of this procedure remains low for both the right internal thoracic artery (RITA) and the radial artery (RA). To identify the optimal arterial conduit to deploy for revascularization of diabetic patients, we compared the outcomes for RA and RITA grafts to the circumflex coronary. METHODS From January 1, 1995, to December 31, 2011, 908 consecutive diabetic patients underwent first-time, isolated CABG (99% on-pump), 659 with the RA and 502 with the RITA, respectively, in two affiliated hospitals. Data were prospectively collected, and late mortality was determined from the Social Security Death Index. Propensity matching, based on preoperative and operative variables, identified 202 matched pairs from each group. RESULTS Long-term survival was similar for matched patients. Mortality, myocardial infarction, reoperation for bleeding, stroke, sepsis, and renal failure were not significantly different between groups. However, deep sternal wound infection (p<0.035) and respiratory failure (p<0.048) favored the RA group, in which the total major adverse events were significantly fewer (p=0.002). CONCLUSIONS In diabetic patients undergoing multivessel revascularization with either RA or RITA grafts to the circumflex coronary, long-term survival is similar. However, RA patients experienced significantly fewer respiratory or sternal wound adverse events. The RA is the preferred conduit to extend to more diabetic patients the recognized survival benefit of a multiple arterial graft strategy.