Lucas B. Ohmes

Three Arterial Grafts Improve Late Survival: A Meta-Analysis of Propensity Matched Studies

Background: Little evidence shows whether a third arterial graft provides superior outcomes compared with the use of 2 arterial grafts in patients undergoing coronary artery bypass grafting. A meta-analysis of all the propensity score-matched observational studies comparing the long-term outcomes of coronary artery bypass grafting with the use of 2-arterial versus 3-arterial grafts was performed. Methods: A literature search was conducted using MEDLINE, EMBASE, and Web of Science to identify relevant articles. Long-term mortality in the propensity score-matched populations was the primary end point. Secondary end points were in-hospital/30-day mortality for the propensity score-matched populations and long-term mortality for the unmatched populations. In the matched population, time-to-event outcome for long-term mortality was extracted as hazard ratios, along with their variance. Statistical pooling of survival (time-to-event) was performed according to a random effect model, computing risk estimates with 95% confidence intervals. Results: Eight propensity score-matched studies reporting on 10 287 matched patients (2-arterial graft: 5346; 3-arterial graft: 4941) were selected for final comparison. The mean follow-up time ranged from 37.2 to 196.8 months. The use of 3 arterial grafts was not statistically associated with early mortality (hazard ratio, 0.93; 95% confidence interval, 0.71–1.22; P=0.62). The use of 3 arterial grafts was associated with statistically significantly lower hazard for late death (hazard ratio, 0.8; 95% confidence interval, 0.75–0.87; P<0.001), irrespective of sex and diabetic mellitus status. This result was qualitatively similar in the unmatched population (hazard ratio, 0.57; 95% confidence interval, 0.33–0.98; P=0.04). Conclusions: The use of a third arterial conduit in patients with coronary artery bypass grafting is not associated with higher operative risk and is associated with superior long-term survival, irrespective of sex and diabetic mellitus status.

Impact of preoperative pulmonary function on outcomes after open repair of descending and thoracoabdominal aortic aneurysms

Objective: To evaluate the impact of preoperative pulmonary function on outcomes after open repair of descending thoracic (DTA) and thoracoabdominal aortic (TAAA) aneurysms. Methods: The outcomes of patients undergoing open repair of DTA or TAAA were analyzed in relation to the results of preoperative pulmonary function tests. Receiver operating characteristic was adopted to assess the effect of forced expiratory volume in one second (FEV1) on the incidence of mortality. Logistic regression analysis and propensity score matching were used. Results: Between 1997 and 2015, 726 patients underwent open DTA or TAAA repair. Pulmonary function tests were available in 711 (97.9%). Receiver operating characteristic analysis revealed the cutoff value of FEV1 to be 50%. Propensity score matching led to 149 pairs of patients with FEV1 below and above 50% with only limited residual imbalance. In the matched population operative mortality was 11.4% and 6.0% in patients with FEV1 ≤ 50% and FEV1 ≥ 51%, respectively (P = .10). The incidence of major adverse events was 33.1% in cases with FEV1 ≤ 50% and 19.5% in those with FEV1 ≥ 51% (P = .008). FEV1 ≤ 50% was associated with a 6.99× increase in the risk of major postoperative adverse events at logistic regression analysis. Conclusions: Preoperative FEV1 < 50% is strongly predictive of increased respiratory failure, tracheostomy, and operative mortality in patients undergoing open DTA/TAAA repair. For these very high‐risk patients with either extensive TAAAs or anatomy unsuitable for endovascular repair, medical therapy may offer the best long‐term survival.

Endoscopic versus open radial artery harvesting: A meta‐analysis of randomized controlled and propensity matched studies

We sought to investigate the impact of radial artery harvesting techniques on clinical outcomes using a meta‐analytic approach limited to randomized controlled trials and propensity‐matched studies for clinical outcomes, in which graft patency was analyzed.

Open repair of descending thoracic and thoracoabdominal aortic aneurysms in patients with preoperative renal failure

OBJECTIVES To evaluate surgical outcomes in open repair of thoracoabdominal aortic (TAAA) and descending thoracic aortic aneurysms (DTA) in patients with preoperative renal failure (PRF). METHODS Our database was examined for all patients undergoing open TAAA/DTA repair. Patients with a creatinine greater than or equal to 1.5 gm/dl or on haemodialysis were defined as having PRF and were compared to those having normal preoperative renal function. Logistic and Cox regression analysis were used to identify independent determinants of in-hospital outcomes and long-term survival. RESULTS From 1997 to 2015, 711 patients underwent open TAAA/DTA repair. Two hundred and two were categorized as having PRF, of which, 22 where on preoperative haemodialysis. PRF patients had significantly worse comorbidities; smoking (95.5% vs 69.0%; P  < 0.001), chronic pulmonary disease (65.8% vs 29.7%; P  < 0.001), peripheral vascular disease (44.1% vs 19.4%; P  < 0.001) and diabetes (16.3% vs 6.7%; vs P  < 0.001). Operative mortality (OM) was seven-times higher in patients with PRF (14.2 vs 2.2%; P  < 0.001). Logistic regression analysis showed that PRF was a predictor of OM [odds ratio (OR): 4.91; confidence interval (CI): 2.01-11.97; P  < 0.001] and major adverse events (OR: 2.05; CI: 1.21-3.46; P  = 0.007). Kaplan-Meier 5-years survival was significantly lower in PRF patients (45.0% vs 69.8%; P  < 0.001). CONCLUSIONS PRF predicts higher OM and major adverse events incidence following open TAAA/DTA repair. Long-term survival is negatively impacted. Strategies for improving preoperative and intraoperative renal function may lead to better outcomes.

Incomplete revascularization and long-term survival after coronary artery bypass surgery

BACKGROUND We sought to investigate the impact of incomplete revascularization (IR) on long-term survival after isolated coronary artery bypass grafting (CABG). The possible interaction between IR and off-pump surgery was also explored. METHODS A total of 13,701 patients with multivessel disease undergoing CABG were included in the analysis. All patients received left internal thoracic artery (LITA) to the left anterior descending artery (LAD) territory. IR was defined as at least one diseased arterial territory (right coronary artery [RCA] and/or circumflex [CX] artery) incompletely revascularized. RESULTS Overall, 3107 (22.7%) patients received IR. After propensity score matching, IR did not increase all-cause death in the overall group (HR 1.09; 95%CI 0.96-1.22; P=0.17). However, when both RCA and CX artery were incompletely revascularized, late survival was significantly lower (HR 2.15; 95%CI 1.57-2.93). IR was associated with a higher risk of death after off-pump (HR 1.26; 95%CI 1.05-1.49) regardless the extent of IR. After on-pump, IR significantly affected survival only when both RCA and CX artery only were incompletely revascularized (HR 2.32; 95%CI 1.27-4.22). CONCLUSIONS The present analysis shows that in patients with LITA-LAD graft the impact of IR on survival is marginal when only one coronary territory is left ungrafted. When both the RCA and CX territory remain unrevascularized the survival rate is significantly reduced. IR after off-pump CABG is associated with significantly lower survival and affects long-term outcome even when only one coronary territory is not revascularized.

New-generation stents compared with coronary bypass surgery for unprotected left main disease: A word of caution

Background: With the advent of bare metal stents and drug‐eluting stents, percutaneous coronary intervention has emerged as an alternative to coronary artery bypass grafting surgery for unprotected left main disease. However, whether the evolution of stents technology has translated into better results after percutaneous coronary intervention remains unclear. We aimed to compare coronary artery bypass grafting with stents of different generations for left main disease by performing a Bayesian network meta‐analysis of available randomized controlled trials. Methods: All randomized controlled trials with at least 1 arm randomized to percutaneous coronary intervention with stents or coronary artery bypass grafting for left main disease were included. Bare metal stents and drug‐eluting stents of first‐ and second‐generation were compared with coronary artery bypass grafting. Poisson methods and Bayesian framework were used to compute the head‐to‐head incidence rate ratio and 95% credible intervals. Primary end points were the composite of death/myocardial infarction/stroke and repeat revascularization. Results: Nine randomized controlled trials were included in the final analysis. Six trials compared percutaneous coronary intervention with coronary artery bypass grafting (n = 4654), and 3 trials compared different types of stents (n = 1360). Follow‐up ranged from 6 months to 5 years. Second‐generation drug‐eluting stents (incidence rate ratio, 1.3; 95% credible interval, 1.1–1.6), but not bare metal stents (incidence rate ratio, 0.63; 95% credible interval, 0.27–1.4), and first‐generation drug‐eluting stents (incidence rate ratio, 0.85; 95% credible interval, 0.65–1.1) were associated with a significantly increased risk of death/myocardial infarction/stroke when compared with coronary artery bypass grafting. When compared with coronary artery bypass grafting, the highest risk of repeat revascularization was observed for bare metal stents (hazard ratio, 5.1; 95% confidence interval, 2.1–14), whereas first‐generation drug‐eluting stents (incidence rate ratio, 1.8; 95% confidence interval, 1.4–2.4) and second‐generation drug‐eluting stents (incidence rate ratio, 1.8; 95% confidence interval, 1.4–2.4) were comparable. Conclusions: The introduction of new‐generation drug‐eluting stents did not translate into better outcomes for percutaneous coronary intervention when compared with coronary artery bypass grafting.

Biological solutions to aortic root replacement: valve-sparing versus bioprosthetic conduit‡

OBJECTIVES Valve-sparing operations and root replacement with a biologic composite conduit are viable options in aortic root aneurysm. This study was conceived to compare the early and mid-term results of these 2 procedures. METHODS From September 2002 to November 2015, 749 consecutive patients underwent either a valve-sparing operation or a root replacement with a biologic composite conduit at 2 institutions. Propensity score matching was used to compare similar cohorts of patients in the overall population and in the ≤ 55 and ≥ 65-year age groups. RESULTS Overall operative mortality was 0.4%, mean age 57.4 ± 14.3 years, 84.6% were male. Individuals in the biologic composite conduit group were older and had worse preoperative risk profiles [chronic pulmonary disease (5.5% vs 0.9%; P  = 0.001), diabetes (6.4% vs 1.5%; P  = 0.001) and NYHA > 2 (25.2% vs 5.2%; P  < 0.001)]. Mean follow-up was 27.5 ± 28.4 months. In the unmatched population, there was no difference in in-hospital deaths (0 in the valve-sparing versus 3 in the biologic composite conduit group; P  = 0.12). These findings were confirmed in the propensity-matched populations. During follow-up, more patients in the biologic composite conduit group underwent reoperation on the aortic valve (2.6% vs 1.5%; P  = 0.026) resulting in a freedom from reoperation of 97.4% vs 98.5%, respectively. Separate analysis for patients stratified by age revealed no difference in outcomes. CONCLUSIONS In case of aortic root aneurysm, both valve-sparing operations and root replacement with a biologic composite conduit provide excellent outcomes. However, at mid-term follow-up the use of biologic composite conduit is associated with a higher risk of reoperation.

Comparison of Outcomes for Off-Pump Versus On-Pump Coronary Artery Bypass Grafting in Low-Volume and High-Volume Centers and by Low-Volume and High-Volume Surgeons

In terms of in-hospital outcomes, controversy still remains whether off-pump coronary artery bypass grafting is superior to on-pump coronary artery bypass surgery. We investigated whether the volume of off-pump coronary artery bypass procedures by hospital and individual surgeon influences patient outcomes when compared with on-pump coronary artery bypass surgery. Discharge records from the Nationwide Inpatient Sample were retrospectively reviewed for in-hospital admissions from 2003 to 2011, including 999 hospitals in 44 states. A total of 2,094,094 patients undergoing on- and off-pump coronary artery bypass surgery were included. In patients requiring 2 or more grafts, off-pump coronary artery bypass compared with on-pump coronary artery bypass was associated with increased risk-adjusted mortality when performed in low-volume centers (<29 cases per year) (odds ratio [OR] 1.32, 95% confidence interval [CI] 1.06 to 1.57) or by low-volume surgeons (<19 cases per year) (OR 1.26, 95% CI 1.02 to 1.56). In high-volume off-pump coronary artery bypass centers (≥164 cases per year) and surgeons (≥48 cases per year), off-pump coronary artery bypass reduced mortality compared with on-pump coronary artery bypass in cases requiring a single graft (OR 0.66, 95% CI 0.49 to 0.89 and OR 0.33, 95% CI 0.22 to 0.47, respectively) or 2 or more grafts (OR 0.82, 95% CI 0.66 to 0.99 and OR 0.63, 95% CI 0.49 to 0.81, respectively). In conclusion, the outcome of off-pump coronary artery bypass grafting procedures is dependent on volume at both the institution and the individual surgeon level. Off-pump coronary artery bypass should not be performed at low-volume centers and by low-volume surgeons.

Gender-related outcomes after open repair of descending thoracic and thoracoabdominal aortic aneurysms

Objective Female sex has been associated with greater morbidity and mortality for a variety of major cardiovascular procedures. We sought to determine the influence of female sex on early and late outcomes after open descending thoracic aortic aneurysm (DTA) and thoracoabdominal aortic aneurysm (TAAA) repair. Methods We searched our aortic surgery database to identify patients having open DTA or TAAA repair. Logistic regression and Cox regression analyses were used to assess the effect of sex on perioperative and long‐term outcomes. Results From 1997 until 2017, there were 783 patients who underwent DTA or TAAA repair. There were 462 male patients and 321 female patients. Female patients were significantly older (67.6 ± 13.9 years vs 62.6 ± 14.7 years; P < .001), had more chronic pulmonary disease (47.0% vs 35.7%; P = .001) and forced expiratory volume in 1 second <50% (28.3% vs 18.2%; P < .001), and were more likely to have degenerative aneurysms (61.7% vs 41.6%; P < .001). Operative mortality was not different between women and men (5.6% vs 6.2%; P = .536). However, women were more likely to require a tracheostomy after surgery (10.6% vs 5.0%; P = .003) despite a reduced incidence of left recurrent nerve palsy (3.4% vs 7.8%; P = .012). Logistic regression found female sex to be an independent risk factor for a composite of major adverse events (odds ratio, 2.68; confidence interval, 1.41‐5.11) and need for tracheostomy (odds ratio, 3.73; confidence interval, 1.53‐9.10). Women also had significantly lower 5‐year survival. Conclusions Women undergoing open DTA or TAAA repair are not at greater risk for operative mortality than their male counterparts are. Reduced preoperative pulmonary function may contribute to an increased risk for respiratory failure in the perioperative period. Graphical Abstract Figure. No Caption available.

Retrograde perfusion through superior vena cava reaches the brain during circulatory arrest

Background The optimal technique for brain perfusion during circulatory arrest remains controversial. Concern exists that retrograde cerebral perfusion (RCP) via the superior vena cava (SVC) is unable to perfuse the brain. We evaluated whether RCP blood circulates through the brain parenchyma in humans during deep hypothermic circulatory arrest (DHCA). We hypothesized that a significant difference in the levels of S-100β (a protein with very high neuro-sensitivity) between the blood infused in the SVC and the effluent blood returning in the left carotid artery (CA) during RCP, should be regarded as a sign of the circulation of RCP blood through the brain parenchyma. Methods We enrolled 10 non-consecutive patients undergoing elective arch-surgery using DHCA and RCP. Circulating S-100β levels were measured at baseline and immediately before DHCA. During DHCA and RCP the difference in S-100β between the SVC and the CA was evaluated after 10 minutes of arrest and immediately before resumption of the circulation. S-100β levels were evaluated using enzyme-linked immunosorbent assay (ELISA). Results Mean DHCA duration was 22.4±7.9 minutes. Mean S-100β level at baseline was 92.5±54.9 µg/L. After 10 minutes of DHCA the level of S-100β in the CA was significantly higher than in the SVC (936.9±326.3 vs. 810.9±307.4 µg/L, P=0.0021). This difference was enhanced at the second DHCA sample (1113.8±334.2 vs. 920.5±340.0 µg/L, P=0.0002). There was a statistically significant correlation between the duration of DHCA and the percent difference in S-100β level between the SVC and the CA (Pearsons correlation coefficient =0.902). Conclusions RCP is able to perfuse the brain parenchyma in humans during DHCA.