Annual case volume on mortality after coronary artery bypass grafting: a dose-response meta-analysis

Pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension in Cape Town, South Africa

Background

Pulmonary endarterectomy (PEA) is the only definitive and potentially curative therapy for chronic thromboembolic pulmonary hypertension (CTEPH), associated with impressive improvements in symptoms and haemodynamics. However, it is only offered at a few centres in South Africa. The characteristics and outcomes of patients undergoing PEA in Cape Town have not been reported previously.

Objectives

To assess the difference in World Health Organization functional class (WHO-FC) before and at least 6 weeks after surgery.

Methods

We interrogated the adult cardiothoracic surgery database at the University of Cape Town between December 2005 and April 2021 for patients undergoing PEA at Groote Schuur Hospital and a private hospital.

Results

A total of 32 patients underwent PEA, of whom 8 were excluded from the final analysis owing to incomplete data or a histological diagnosis other than CTEPH. The work-up of these patients for surgery was variable: all had a computed tomography pulmonary angiogram, 7 (29%) had a ventilation/perfusion scan, 5 (21%) underwent right heart catheterisation, and none had a pulmonary angiogram. The perioperative mortality was 4/24 (17%): 1 patient (4%) had a cardiac arrest on induction of anaesthesia, 2 patients (8%) died of postoperative pulmonary haemorrhage, and 1 patient (4%) died of septic complications in the intensive care unit. Among the survivors, the median (interquartile range) improvement in WHO-FC was 2 (1 - 3) classes (p=0.0004); 10/16 patients (63%) returned to a normal baseline (WHO-FC I).

Conclusion

Even in a low-volume centre, PEA is associated with significant improvements in WHO-FC and a return to a normal baseline in survivors.

Study synopsis

What the study adds. South African patients undergoing pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have a marked improvement in functional status, with many returning to a normal functional baseline. However, the small number of patients included in this study indicates that PEA is probably underutilised. Pre- and postoperative assessment is inconsistent, despite availability of established guidelines.Implications of the findings. More patients should be referred to specialist centres for assessment for this potentially curative procedure. Use of guidelines to standardise investigations and monitoring of patients with CTEPH may improve patient selection for surgery.

Annual Case Volume and One-Year Mortality for Endovascular Treatment in Acute Ischemic Stroke

BACKGROUND

The association between endovascular treatment (EVT) case volume per hospital and clinical outcomes has been reported, but the exact volume threshold has not been determined. This study aimed to examine the case volume threshold in this context.

METHODS

National audit data on the quality of acute stroke care in patients admitted via emergency department, within 7 days of onset, in hospitals that treated ≥ 10 stroke cases during the audit period were analyzed. Ischemic stroke cases treated with EVT during the last three audits (2013, 2014, and 2016) were selected for the analysis. Annual EVT case volume per hospital was estimated and analyzed as a continuous and a categorical variable (in quartiles). The primary outcome measure was 1-year mortality as a surrogate of 3-month functional outcome. As post-hoc sensitivity analysis, replication of the study results was examined using the 2018 audit data.

RESULTS

We analyzed 1,746 ischemic stroke cases treated with EVT in 120 acute care hospitals. The median annual EVT case volume was 12.0 cases per hospital, and mortality rates at 1 month, 3 months, and 1 year were 12.7%, 16.6%, and 23.3%, respectively. Q3 and Q4 had 33% lower odds of 1-year mortality than Q1. Adjustments were made for predetermined confounders. Annual EVT case volume cut-off value for 1-year mortality was 15 cases per year (P < 0.02). The same cut-off value was replicated in the sensitivity analysis.

CONCLUSION

Annual EVT case volume was associated with 1-year mortality. The volume threshold per hospital was 15 cases per year.

The impact of trainees' working hour regulations on outcome in CABG and valve surgery in the State of New York

BACKGROUND AND AIM

In 2011, the Accreditation Council for Graduate Medical Education (ACGME) restricted the first-year residents' duty-hour to less than 16-hour shifts, decreased the maximum shift duration for senior residents, and increased minimum time off after on-call duties. Whether these changes may have impacted the outcomes in cardiac surgery remains unclear.

METHODS

We performed a difference-in-difference analysis of the New York State Cardiac Surgery Reporting System data in 2004-2006 (before the duty-hour policies change) and 2014-2016 (after the change). We evaluated differences in 30-day risk-adjusted mortality rates (RAMR) in coronary artery bypass grafting (CABG) and valve surgeries, stratifying data by hospital type: teaching hospitals (TH) versus nonteaching hospitals (NTH). NTH served as the control not affected by the duty-hour policies.

RESULTS

(1) The overall surgical volume for CABG surgery has decreased over time (37,645-24,991), while the volume for valve surgery remained similar (20,969-21,532); (2) TH had better short-term outcomes for CABG procedures during 2014-2016 (median RAMR: 1.01% vs. 1.55% in TH vs. NTH, respectively; p = .025) as well as for valve procedures during both 2004-2006 (5.16% vs. 7.49%, p = .020) and 2014-2016 (2.59% vs. 4.09%, p = .033); (3) at difference-in-difference analysis, trainees' duty-hour regulations were not associated with worsening short-term outcomes in both CABG (p = .296) and valve (p = .651) procedures performed in TH.

CONCLUSION

The introduction of the 2011 trainees' duty-hour regulations was not associated with worse short-term outcomes for CABG and valve surgery performed in the State of NY by TH.

Perioperative outcomes of coronary artery bypass graft surgery in Johannesburg, South Africa

Background

The perioperative complications in patients with coronary artery disease undergoing coronary artery bypass graft (CABG) surgery have been reported predominantly from developed countries, with a paucity of data from sub-Saharan Africa. We aim to report on the clinical characteristics and perioperative complications in patients with obstructive coronary artery disease, managed with CABG surgery at a tertiary academic hospital in Johannesburg, South Africa.

Methods

We retrospectively reviewed data from adult patients who underwent CABG surgery during a 17-year period (January 2000 – December 2017). Data was collected from the cardiothoracic surgery department’s pre- and postoperative reports, the cardiology department’s medical records, and anaesthesiology’s intra-operative reports. We collected demographic, biochemical, clinical, surgical, echocardiographic, and angiographic data. Outcomes data collected included perioperative complications and mortality.

Results

We analysed 1218 consecutive patient records. The study cohort consisted of 951 (78.1%) males, and the mean age was 60.1 ± 10.1 years. During the study period, 137 (11.2%) patients demised with cardiac and sepsis-related causes of death accounting for 49.6 and 37.2%, respectively. Other perioperative complications included excessive bleeding in 222 (18.2%), prolonged ventilation (exceeding 48 h) in 139 (11.4%), and sternal sepsis in 125 (10.3%). On univariate logistic regression analysis, advanced age, a lower left ventricular ejection fraction, smoking, increased cardiopulmonary bypass (CPB) time, and a higher European System for Cardiac Operative Risk Evaluation (EuroSCORE) II were all significantly associated with mortality. The EuroSCORE II [OR: 0.15 95%CI: 0.09–0.22; p = 0.000], and prolonged CPB time [OR: 0.01 CI: 0.00–0.02; p = 0.000] were independent predictors of in-hospital all-cause mortality.

Conclusions

In our study, the crude perioperative mortality rate was 11.2%. Our mortality rate was significantly higher than the mortality rates reported in other developed and developing countries. To better understand the factors driving this high mortality rate, a prospective outcomes registry has been initiated, and this promises to inform on our contemporary mortality and morbidity outcomes.