Completeness of revascularization in multivessel coronary artery disease

Myocardial work in patients with heart failure and ischemic cardiomyopathy according to the mode of coronary revascularization

BACKGROUND

The association of percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) on myocardial function, as reflected in myocardial work (MyW) parameters, in patients with ischemic cardiomyopathy and heart failure (HF) is unknown.

METHODS

We analyzed data from 68 patients who were hospitalized with chronic HF due to ischemic cardiomyopathy and stratified them according to the mode of revascularization. All patients underwent a 2D speckle tracking echocardiography exam performed by the same expert sonographer and had complete MyW data including global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE).

RESULTS

The mean age of patients was 70 ± 10 years and 86.8% were men. The mean left ventricular ejection fraction (LVEF) in overall cohort was 31.6 ± 9.5%. Both subgroups did not significantly differ in terms of baseline LVEF, comorbidities, and pharmacotherapy. Compared with those who received PCI, patients revascularized with CABG had significantly greater GWI (821 vs. 555 mmHg%, p = 0.002), GCW (1101 vs. 794 mmHg%, p = 0.001), GWE (78 vs. 72.6%, p = 0.025), and global longitudinal strain (-8.7 vs. -6.7%, p = 0.004). Both patient subgroups did not significantly differ with respect to GWW (273 vs. 245 mmHg%, p = 0.410 for CABG and PCI, respectively) and survival during the median follow-up of 18 months (log-rank p = 0.813).

CONCLUSION

Patients with HF and ischemic cardiomyopathy revascularized with CABG had greater myocardial work performance when compared with those revascularized with PCI. This might suggest a higher degree of functional myocardial revascularization associated with the CABG procedure.

Long-term survival following postoperative myocardial infraction after coronary artery bypass surgery

BACKGROUND

Postoperative myocardial infraction (MI) is a serious complication among patients undergoing Coronary Artery Bypass Grafting (CABG). Data on the impact of postoperative MI on patients undergoing CABG, specifically with respect to their long term outcomes are sparse.

METHODS

We retrospectively analyzed all patients who underwent isolated CABG between January 2014 and December 2016 and identified those who fulfilled the definition of the type 5MI following CABG according to the Fourth Universal Definition of Myocardial Infarction.

RESULTS

A total of 4,642 CABG patients were identified, of whom 141 (3.04%) were diagnosed with postoperative MI. The mean follow-up time was 5.1±2.07 years (range, 4.4-6.9 years). Postoperative MI was more common in patients with recent acute coronary syndrome, when compared to stable angina (22.8% vs. 31.9%; P=0.011) and in those with non-elective versus planned surgery (28.4% vs. 18.4%; P=0.003). Postoperative MI after CABG was associated with an increased rate of postoperative complications, including cardiac tamponade and re exploration for bleeding. Mortality after postoperative MI was higher at short-term follow-up (up to one year) and long-term follow-up (up to five years). The risk factors for postoperative MI after CABG were incomplete revascularization (IR) [OR (95% CI): 2.25 (1.59-3.12), P=0.001], non-elective surgery [OR (95% CI): 1.68 (1.10-2.54), P=0.015] and female gender [OR (95% CI): 1.48 (1.01-2.18), P=0.045].

CONCLUSIONS

PMI after CABG is associated with reduced short- and long-term survival. The main risk factors for postoperative MI are IR, female gender, and non-elective surgery.

Sex Differences in Coronary Artery Bypass Grafting Techniques: A STS Database Analysis

BACKGROUND

Females with coronary artery disease (CAD) have inferior outcomes compared with males, including higher mortality following coronary artery bypass grafting (CABG). We aimed to evaluate the association of female sex with the use of guideline-concordant CABG revascularization techniques.

METHODS

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database was queried for adult patients who underwent first-time isolated CABG in the US from 2011-2019. The association between female sex and the odds of (1) receiving a left internal mammary artery (LIMA) graft for revascularization of the left anterior descending (LAD) artery, (2) undergoing complete revascularization, and (3) undergoing multi-arterial grafting was assessed, adjusting for procedural anatomy.

RESULTS

Among 1,212,487 patients meeting inclusion criteria, 75% were male (n=911,178) and 25% were female (n=301,309). Female sex was associated with lower unadjusted rates of revascularization with an IMA (93.9% vs 95.9%, P<.001), bilateral IMA (2.9% vs 5.6%, P<.001) or radial artery (3.2% vs 5.6%, P<.001) graft. After adjustment, females had a lower odds than males of receiving a LIMA graft to the LAD (adjusted odds ratio [AOR] 0.79, 95% CI 0.75-0.83, P<.001), undergoing complete revascularization (AOR 0.86, 95% CI 0.83-0.90, P<.001), and undergoing multi-arterial grafting (AOR 0.78, 95% CI 0.75-0.81, P<.001).

CONCLUSIONS

Female sex was associated with a 14-22% lower odds of undergoing guideline concordant revascularization including LIMA to LAD grafting, multi-arterial grafting, and complete revascularization. Further investigation is necessary to determine why revascularization approaches differ by sex and to what degree sex disparities in CAD outcomes are due to surgical approach.

Coronary artery bypass grafting in patients with low ejection fraction: what are the risk factors?

BACKGROUND

Left ventricular (LV) dysfunction alone is insufficient as an independent predictor of postoperative complications and mortality in coronary artery bypass graft (CABG) surgery. Our objective was to identify additional independent risk factors in patients with low left ventricle ejection fraction (EF) who underwent CABG.

METHODS

We retrospectively analyzed CABG results of 346 consecutive patients with low EF (≤30%) in a single institution between 2009 and 2015. The primary study endpoint was 30-day all-cause mortality. The secondary endpoints were the development of major adverse cardiac events (MACE) and renal complications after operation. A subgroup of patients underwent additional analyses of the interaction between extents of viable myocardium and postoperative endpoints.

RESULTS

The analysis showed that preoperative hemodynamic instability (AOR=4.57; 95% CI: 1.53-13.7, P=0.007) and serum creatinine >166 µmol/L (AOR=3.46; 95% CI: 1.12-10.7, P=0.031) were independent predictors of 30-day death. Both urgent and emergency operations were predictors for MACE (P=0.038; P=0.005) and renal complications (P=0.004; P=0.007). Pre-existing diabetes mellitus increased the likelihood of renal complications (P=0.020). In the sub-analysis of patients with viable myocardium, the mortality was significantly lower with predicted mortality (P=0.014).

CONCLUSIONS

Patients with significant LV dysfunction undergoing isolated CABG have fair short-term survival even with EF less than 30%. Hemodynamic instability prior to operation and preoperative kidney dysfunction are strong predictors of mortality in patients with low EF. Favorable coronary targets, meticulous operative techniques, and optimal surgical timing before hemodynamic deterioration occurs are essential to minimize the risk of revascularization complications and early postoperative mortality.