Norihiko Hiramatsu

Safety and efficacy of central cannulation through ascending aorta for type A aortic dissection

The femoral and axillary arteries are common arterial cannulation sites for repair of type A dissection. However, these peripheral approaches involve certain problems. From January 2002 to August 2009, a total of 77 patients underwent emergency surgery for acute type A dissection. Central cannulation was applied in 26 patients and peripheral cannulation in 51. The arterial cannulation site was decided according to preoperative computed tomography findings, the patients condition, and intraoperative epiaortic ultrasonography findings. Central cannulation was avoided in cases of cardiac tamponade with shock. A cannula was inserted under ultrasound guidance using the Seldinger technique. Preoperative patient comorbidities and dissection-related complications were equally distributed between the two groups. Central cannulation was successfully performed in all 26 cases without incident. Operation time, cardiopulmonary bypass time, mean intubation time and mean intensive care unit stay duration were significant shorter in the central group. One patient (4%) died in the central group compared with four patients (8%) in the peripheral group (P=0.45). Direct central cannulation was successful for repair of type A dissection in selected patients and produced equal or superior surgical data to peripheral cannulation, thus providing one option in the approach to this condition.

Efficacy of Bilateral Internal Thoracic Artery Grafting in Patients With Chronic Kidney Disease

BACKGROUND This study compared short-term and long-term outcomes in propensity score-matched patients with chronic kidney disease receiving bilateral internal thoracic artery (ITA) or single ITA grafting and assessed any benefit of bilateral ITA grafting for survival. METHODS Among 656 consecutive patients undergoing isolated coronary artery bypass grafting (99.1% by off-pump technique) between 2002 and 2008, 361 had chronic kidney disease with no history of dialysis. After excluding 10 patients who would not be potential candidates for bilateral ITA grafting because they were aged older than 85 years and 15 who had only one target vessel at the left coronary area, we identified 157 propensity score-matched pairs. Propensity scores were created based on 13 preoperative factors (C statistics, 0.787). RESULTS During a mean observation of 2.9 years, the rates of overall death and cardiac death (myocardial infarction, heart failure, and sudden death) in the bilateral ITA group were significantly lower than those in the single ITA group (5.1% vs 15.9%, p=0.01; 1.3% vs 8.3%, p=0.01). In multivariate Cox models including bilateral ITA grafting and all other potential predictors, bilateral ITA grafting was significantly associated with a lower risk for overall death (hazard ratio, 0.29; 95% confidence interval, 0.10 to 0.89; p=0.03) and cardiac death (hazard ratio, 0.14; 95% confidence interval, 0.03 to 0.63; p=0.02). CONCLUSIONS Among patients with chronic kidney disease, bilateral ITA grafting provides better long-term survival than single ITA grafting.

Bilateral versus Single Internal Thoracic Artery Grafting in Dialysis Patients with Multivessel Disease

BACKGROUND The purpose of our study was to compare mortality in dialysis patients undergoing bilateral internal thoracic artery (BITA) or single internal thoracic artery (SITA) grafting and to quantify the magnitude of the BITA grafting benefit for survival. METHODS Between January 2002 and December 2008, 656 consecutive patients underwent isolated coronary artery bypass grafting (99.1% by an off-pump technique). Fifty-six of these patients with chronic dialysis and multivessel disease were retrospectively compared with respect to surgical technique: BITA (n = 32) or SITA (n = 23) grafting. End points were all-cause and cardiovascular mortality (mean follow-up duration, 2.5 years). In an attempt to minimize the selection bias, we created propensity scores based on 13 preoperative factors that would affect the surgeons decision about operative strategy; these factors were used for regression adjustment (C statistic, 0.914). RESULTS There were no significant differences between the 2 groups with respect to age, sex, left ventricular ejection fraction, prevalence of diabetes mellitus and peripheral arterial disease, and logistic EuroSCORE. All patients under-went revascularization with the off-pump technique, with no conversion to cardiopulmonary bypass. All arterial conduits were harvested with a skeletonization technique in all cases. Except for 1 patient who received a SITA, internal thoracic arteries were used as in situ grafts in both groups. Complete revascularization was achieved in all patients. The 1-, 3-, and 5-year survival rates free from all-cause mortality for BITA grafting versus SITA grafting were 94% versus 73%, 72% versus 42%, and 52% versus 28%, respectively (P = .01, logrank test). For survival free from cardiovascular mortality, the respective rates were 100% versus 90%, 80% versus 77%, and 80% versus 58% (P = .06). After propensity score adjustment, BITA grafting was significantly associated with lower risks for all-cause mortality (hazard ratio, 0.27; 95% confidence interval, 0.09-0.81; P = .02) and cardiovascular mortality (hazard ratio, 0.20; 95% confidence interval, 0.04-0.93; P = .04). CONCLUSION In situ skeletonized BITA grafting provides better long-term survival in dialysis patients with multivessel disease.

Left Main Coronary Artery Disease Does Not Affect the Outcome of Off-Pump Coronary Artery Bypass Grafting

BACKGROUND Left main coronary artery (LMCA) stenosis (≥50%) has historically been recognized as a risk factor among patients undergoing coronary artery bypass grafting. METHODS From January 2002 to December 2008, a total of 665 patients, 268 of whom had significant LMCA disease, underwent isolated off-pump coronary artery bypass surgery at Shiga Medical University Hospital. We compared the clinical results in the 237 patients with LMCA stenosis (LMCA group) with those in the propensity score-matched 237 patients without LMCA stenosis (non-LMCA group). We performed off-pump surgery in all coronary artery bypass grafting cases with no exclusion criteria. RESULTS All procedures were performed by off-pump technique without conversion to on-pump. Two patients in the LMCA group (2 of 237; 0.8%) and four in the non-LMCA group (4 of 237; 1.7%) died within 30 days after surgery. Follow-up was completed in 96.2% of the patients. The rates of six-year freedom from all cause death were 87.3% and 60.7% in the LMCA group and non-LMCA group, respectively (p = 0.17), and the corresponding rates for the combined endpoint of cardiac death, myocardial infarction, angina pectoris, repeat coronary intervention, and heart failure were 80.4% and 70.4% (p = 0.98). Multivariate Cox regression analysis revealed chronic renal failure as a statistically significant predictor for late cardiac event. CONCLUSIONS Off-pump coronary artery bypass grafting is feasible and safe in patients with critical LMCA stenosis and LMCA disease is not recognized as a risk factor after off-pump coronary artery bypass grafting in either the short or the long term.

Does off-pump bilateral internal thoracic artery grafting increase operative risk in dialysis patients?

BACKGROUND We compared short-term outcomes of patients with chronic dialysis receiving bilateral internal thoracic artery (BITA) grafting with single internal thoracic artery (SITA) grafting using propensity score analysis. METHODS Between 2002 and 2008, 656 consecutive patients underwent isolated coronary artery bypass grafting (99.1% off-pump). Of these, 56 patients with chronic dialysis and multivessel disease were retrospectively compared according to surgical technique, BITA (n = 32) or SITA (n = 23) grafting. In an attempt to minimize the selection bias, propensity scores were created based on 13 preoperative factors (C statistics, 0.914). RESULTS There was no significant difference in age, left ventricular ejection fraction, prevalence of diabetes mellitus, and logistic euroSCORE between the 2 groups. All patients underwent revascularization using the off-pump technique without conversion to cardiopulmonary bypass. All arterial conduits were harvested using skeletonization technique. Except for 1 patient, all ITAs were used as in situ graft. Complete revascularization was achieved in all patients. There was no significant difference in occurrence of mediastinitis, impaired wound healing, and stroke between the 2 groups. The 30-day mortality was 6.3% in the BITA group and 13.0% in the SITA group (P = .64). After adjusting for propensity score, BITA grafting was not associated with impaired wound healing (odds ratio, 0.63; 95% confidence interval, 0.04 to 8.79; P = .73) and 30-day mortality (odds ratio, 0.60; 95% confidence interval, 0.05 to 6.82; P = .68). CONCLUSION In situ skeletonized BITA grafting is safe and feasible in dialysis patients with multivessel disease.