Long-term outcomes following coronary artery bypass grafting: the role of off-pump strategy

Background

The debate on the advantages and limitations of off-pump (OPCAB) on long-term outcomes has not still arrived to a conclusion. This study was designed to compare the impact of OPCAB vs on-pump coronary artery bypass grafting (CABG) on long-term mortality and major adverse cardiac events (MACEs).

Methods

The PRIORITY project was designed to evaluate the long-term outcomes of 2 large prospective multicenter cohort studies on CABG conducted between 2002–2004 and 2007–2008. Data on isolated CABG were linked to 2 administrative datasets. Time-to-event methods were employed to analyze outcomes.

Results

The population consisted of 11021 patients who underwent isolated CABG (27.2% OPCAB) that were divided into development and validation datasets. The median follow-up time was 8 years (interquartile range 7.6–10 years) and was 100% complete. Unadjusted long-term survival was significantly worst for OPCAB, nonetheless the adjustment did not confirm OPCAB as a risk factor for mortality (HR 0.94, 95% CI 0.85–1.03, p=0.19). OPCAB was associated to an increased risk of MACE at 10 years (adjusted HR 1.14, 95% CI 1.06–1.23, p=0.001). Inside the MACEs, OPCAB was significantly related to increased incidence of rehospitalization for percutaneous cardiac intervention (PCI), (adjusted HR 1.33, 95% CI 1.16–1.53, p<0.001), demonstrating to be an independent risk factor for PCI with an hazard that is 33% higher than on-pump CABG.

Conclusions

OPCAB did not affect long-term mortality but is associated with an increased long-term risk of repeat PCI. These findings may have important implications towards health resources allocation, particularly in a climate of cost containment of healthcare expenditures.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Italian Minister of Health

Can double internal thoracic artery grafts affect 10-year outcomes after coronary artery bypass grafting?

Background

The advantages of the employment of double internal thoracic artery grafts (BITA) for coronary artery bypass grafting have been recently questioned and no data on long-term follow-up are available. This observational retrospective cohort study was designed by the PRIORITY planning committee to evaluate 10-year follow-up of isolated CABG performed with and without BITA in order to clarify and consolidate the contrasting literature.

Methods

The PRIORITY project was designed to evaluate the long-term outcomes of 2 large prospective multicenter cohort studies on CABG conducted between 2002–2004 and 2007–2008. Data on isolated CABG were linked to 2 administrative datasets. Time-to-event distributions were separately analyzed accordingly to primary event-type (death, MACEs), using Kaplan-Meier estimates and Cox regression.

Results

The population consisted of 11021 patients who underwent isolated CABG that were divided into development and validation datasets; double thoracic internal artery grafts was employed in 24.6%. The median follow-up time was 8 years (interquartile range 7.6–10 years) and was 100% complete. After adjustment for potential confounding factors, BITA was significantly associated with better survival (HR 0.85, 95% CI 0.76–0.95, p=0.003). Moreover, the employment of BITA reduced the incidence of MACEs at follow-up (adjusted HR 0.87, 95% CI 0.80–0.94, p=0.001). In details, BITA was demonstrated to be a protective factor for acute myocardial infarction (adjusted HR 0.84, 95% CI 0.71–0.99, p=0.05) and for rehospitalization for percutaneous cardiac intervention (PCI; adjusted HR 0.82, 95% CI 0.70–0.96, p=0.013).

Conclusions

The employment of double internal thoracic artery grafts for coronary artery bypass grafting has been associated to survival advantage at 10-year. Moreover, it significantly decreased the incidence of acute myocardial infarction and rehospitalization for percutaneous cardiac intervention.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Italian Minister of Health

Diabetes mellitus in transfemoral transcatheter aortic valve implantation in 11,440 patients from the CENTER collaboration

Background

Diabetes mellitus (DM) is a well-known cardiovascular risk factor present in up to a third of patients undergoing transcatheter aortic valve implantation (TAVI). How DM might influence outcomes after TAVI procedures remains controversial. The aim of this study was to determine differences in outcomes after TAVI according to diabetes status.

Methods

The CENTER (Cerebrovascular EveNts in patients undergoing TranscathetER aortic valve implantation with balloon-expandable valves versus self-expandable valves)-collaboration was a global patient level dataset of patients undergoing transfemoral TAVI from 2007 to 2018. In this analysis, the study examined differences in baseline patient characteristics, 30-day stroke and mortality, and in-hospital outcomes between DM and non-DM patients.

Results

Of the 11,440 patients included, 31% (n=3,550) were diabetic and 69% (n=7,890) were non-diabetic. Diabetics were younger, had a higher body mass index (BMI) and overall a worse cardiovascular risk profile than non-diabetics. There were no differences between DM and non-DM patients regarding in-hospital mortality (4.8% vs 5.3%, RR: 0.9, 95% CI: 0.7–1.1, p=0.46), myocardial infarction (0.9% vs 0.7%, RR: 1.4, 95% CI: 0.9–2.2, p=0.17), stroke (1.7% vs 2.0%, RR: 0.9, 95% CI: 0.6–1.2, p=0.36), major or life threatening bleeding (5.9% vs 6.3%, RR: 0.9, 95% CI: 0.8–1.1, p=0.44) and permanent pacemaker implantation (13.6% vs 13.4%, RR: 1.0, 95% CI: 0.9–1.1, p=0.69). Similarly, 30-day rates of all-cause mortality (5.4% vs 6.1%, RR: 0.9, 95% CI: 0.8–1.1, p=0.30) and stroke (2.0% vs 2.4%, RR: 0.8, 95% CI: 0.6–1.1, p=0.23) did not differ between diabetic and non-diabetic patients. Accordingly, in multivariate analysis, DM was not an independent predictor of mortality.

Conclusions

In this global collaboration, diabetic patients undergoing transcatheter aortic valve replacement had more cardiovascular comorbidities, were younger and had a higher body mass index than non-diabetics. They had similar periprocedural complications, in-hospital and 30-day mortality rates. In multivariate analysis, diabetes was not associated with increased mortality.

Predicted vs observed mortality in DM

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Dutch Heart Foundation; the Netherlands Organisation for Health Research and Development

Long-term outcome after off-pump coronary artery bypass grafting: implication for public health

Background

The debate on the benefits and limitations of off-pump (OPCAB) coronary artery bypass grafting (CABG) on long-term outcomes is not yet settled. This study aimed to compare the impact of OPCAB vs on-pump CABG on long-term outcomes and to evaluate possible public health implications linked to their use.

Methods

The PRIORITY project was planned to evaluate the long-term outcomes of two prospective multicenter studies on CABG conducted between 2002-2004 and 2007-2008. Data on isolated CABG were linked to administrative data in order to retrieve patients' late outcome. Time-to-event distributions were analyzed accordingly to primary event-type (death, major adverse cardiac events (MACEs)) using the Kaplan-Meier and the Cox proportional hazards methods.

Results

The study population consisted of 11 021 patients who underwent isolated CABG (27.2% OPCAB). The median follow-up time was 8.0 years (interquartile range 7.6-10.0 years). OPCAB had comparable late all-cause mortality to on-pump CABG (HR 0.94, 95%CI 0.85-1.03, p = 0.19), but it was associated to an increased risk of MACE (adjusted HR 1.14, 95%CI 1.06-1.23, p = 0.001). In particular, OPCAB had an increased risk of repeated revascularization with percutaneous cardiac intervention (PCI) (adjusted HR 1.33, 95%CI 1.16-1.53, p < 0.001) compared to on-pump CABG.

Conclusions

OPCAB does not affect long-term mortality, but it significantly increases the risk of MACEs. In particular, OPCAB had an increased risk of repeated revascularization with PCI. These findings may have important implications towards health resources allocation.

Key messages

Off-pump coronary artery bypass grafting strategy is associated with an increased long-term risk of MACE and repeated PCI. Off-pump strategy is mainly based on operator preferences and can have important implications in terms of healthcare costs.

Trends in mortality and heart failure after acute myocardial infarction in Italy from 2007 to 2017

Background

Uncertainties on long-term outcomes after acute myocardial infarction (AMI) still exist, despite the ongoing progresses in the management of patients with AMI. This study aims to appraise early and 1-year outcome of patients hospitalized due to AMI and to describe the role of heart failure (HF) as complication affecting prognoses.

Methods

Retrospective nationwide cohort study based on administrative data on patients with AMI admitted in all Italian hospitals from 2007 to 2017. Index admission mortality rate (I-MR), 30-day and 1-year post-discharge mortality rate (PD-MR), and 30-day and 1-year total mortality rate (T-MR) were analysed; mortality average annual changes (AC) and their 95% CI were calculated; the Cox model, adjusting for age, sex, comorbidities and length of stay, was used to analyse 1-year PD-MR

Results

1,148,820 patients were considered. From 2007 to 2017, both I-MR and T-MR up to 1 year decreased significantly (from 10.9 to 8.4%; AC: -0.28%; CI: -0.31 to -0.25 and from 20.2% to 17.1%: AC: -0.33%; CI: -0.39 to -0.28, respectively). From 2010, also the rate of PD-MR decreased significantly from 11.7% to 10.4%, with such favourable trend confirmed at multivariable analyses. The HF diagnosis at the index admission is always associated with a significant increase in the risk of death (1-year T-MR average: 43% and 12% in patients with or without HF, respectively; both patients with and without HF show a constant improvement in I-MR, T-MR and PD-MR over time.

Conclusions

In the last decade, the remarkable improvements in the in-hospital treatment of patients with AMI and in the overall prognosis up to 1 year are confirmed by a constant decrease in both early and long-term mortality. Since complication from HF remains a dangerous condition that significantly worsens the prognosis of the AMI patient, appropriate management strategies must be identified and implemented to guarantee best results from both clinic and public health perspective.

Key messages

Remarkable improvements achieved in overall prognosis after AMI over the past 10 years. HF confirms to be a condition able to worsen AMI patients’ prognosis.

Hospitalization costs related to long-term management of patients undergoing CABG (PRIORITY project)

Background

Identifying potential tools that could help improving the standard of care and lead to a better allocation of economic resources represents a main objective of research in public health. Using data from the PRIORITY cohort, this study aims to describe inpatients costs after a discharge for isolated coronary artery bypass surgery (CABG).

Methods

The PRIORITY project was designed to evaluate the long-term outcomes of 2 large multicenter cohort studies on CABG conducted between 2002-04 and 2007-08. For each patient discharged alive after a CABG intervention, costs of hospitalizations were estimated as the sum of costs of all the admissions occurred during 3 years of follow-up. NHS reimbursement rates were used as standard costs (in Euros). Inpatients costs were analysed according to their baseline risk factors.

Results

Among the 7363 patients included in this analysis, the median 3-year hospitalization costs were 4341€ (IQR: 1865-11699). Median costs were around 4.000€ for subjects alive at the end of follow up but higher for patients dying within 1 (about 8.600€) and 2-3 years of follow up (about 20.000€). The presence of comorbidities (such as diabetes and cancer) lead to higher median hospitalization costs while the on-pump approach was associated to lower median cost. Sixteen per cent of patients were at zero cost having no re-hospitalizations during the 3 years of follow-up (97% alive). Subjects at zero cost received more frequently on-pump approach, had a lower frequency of cancer, arteriopathy and ictus, but a higher frequency of angina and infarction.

Conclusions

Inpatient costs after isolated CABG are affected by preoperative comorbidities and by operative variables that could be removed or managed. Identifying independent risk factors for re-hospitalization will lead to the definition of a preoperative clinical and decision-making path that will bring both a clinical advantage for the patient and an optimization of costs for the NHS.

Key messages

Inpatient costs after isolated CABG are affected by preoperative comorbidities and operative characteristics like the on-pump approach. Appropriate management of operative approaches mainly based on operator preferences can have important implications in terms of healthcare costs.

Bilateral internal thoracic artery grafting in coronary surgery: 10-year outcomes

Background

The advantages to use the bilateral internal thoracic artery grafting (BITA) technique for coronary artery bypass grafting (CABG) have been recently questioned, but data on long-term follow-up is limited. Using data from the PRIORITY project, this study aims to assess the outcome with the use of BITA grafting and its implications for public health.

Methods

The PRIORITY project was planned to evaluate the long-term outcomes of two prospective multicenter studies on CABG conducted between 2002-2004 and 2007-2008. Data on isolated CABG were linked to administrative data in order to retrieve patients' late outcome. Time-to-event distributions were analyzed accordingly to primary event-type (death, major adverse cardiac events (MACEs)) using the Kaplan-Meier and the Cox proportional hazards methods.

Results

The study population consisted of 11021 patients who underwent isolated CABG. BITA grafting was employed in 24.6% of patients. The median follow-up time was 8.0 years (interquartile range 7.6-10.0 years). After adjustment for potential confounding factors, BITA grafting was significantly associated with better survival (HR 0.85, 95%CI 0.76-0.95, p = 0.003). Moreover, using BITA grafting reduced the incidence of MACE (HR 0.87, 95%CI 0.80-0.94, p = 0.001), showing to be a protective factor for recurrent acute myocardial infarction (HR 0.84, 95%CI 0.71-0.99, p = 0.05) and for rehospitalization for percutaneous cardiac intervention (HR 0.82, 95%CI 0.70-0.96, p = 0.013).

Conclusions

BITA grafting during isolated CABG is associated with survival advantage at 10-year with a significantly reduced incidence of MACE. Being the choice to perform isolated CABG with or without BITA based mainly on operator personal preferences, these findings may have important implications from a public health perspective.

Key messages

The choice to perform CABG with or without BITA grafting is associated to different outcomes. The choice to perform CABG with or without BITA grafting is mainly based on operator preferences and may have important implications in terms of healthcare expenditures.

Hospital management of patients with acute coronary syndrome: influence of age and gender

Background

Although the improvement of therapeutic strategies is leading to a dramatic decline of in-hospital acute coronary syndrome (ACS) death rates, differences in care and prognosis of ACS patients exist when age, gender and admission department are considered.

Methods

The national administrative hospital discharge record (HDR) system was used. Only data recorded from January 1, 2017 to Dicember 31, 2018 were analyzed. This approach allowed to identify 205775 patients reporting ACS as primary or secondary diagnosis: 122812 with non-ST-elevation ACS (NSTE-ACS) and 82963 with ST-elevation ACS (STEMI). The ACS cohort was stratified by age (<75 and ≥75 years) and gender. The proportion of STEMI patients treated in general medicine or cardiology departments requiring a coronary procedure or extensive investigations were analyzed.

Results

Among the 205775 patients hospitalized for ACS, 6% of STEMI and 8.3% of NSTE-ACS patients have been treated only in a general medicine ward and have never passed through a specific cardiology ward. For STEMI patients, the proportion becomes 4% when males are considered, increases up to 10% for females and up to 13% for elderly patients (≥75 years). During the index hospitalization, about 25% of female and more than 30% of elderly patients with STEMI do not undergo a coronary procedure or other extensive investigations; the same happens only in about 10% of male and 6% of younger patients. The proportion of improperly managed patients reaches 35% for women aged ≥75 years.

Conclusions

In-hospital management of women and elderly patients with ST-elevation ACS does not completely comply with the recommended guidelines and exposes them to unfavourable prognosis.

Key messages

Women and elderly STEMI patients are markedly less intensively investigated and treated in cardiologic departments. This medical policy could lead to unfavourable prognosis.

Relationship between B-type natriuretic peptide levels and ventilatory response during cardiopulmonary exercise test in patients with chronic heart failure

AIM

Aim of the study was to evaluate if brain natriuretic peptide (BNP) levels, a cardiac neurohormone well correlated with prognosis in chronic heart failure (CHF), are associated with enhanced ventilatory response to exercise, in ambulatory patients with intermediate peak oxygen uptake (PVO2).

METHODS

Resting BNP was measured in 129 consecutive stable CHF patients with mild to moderate heart failure (90% New York Heart Association (NYHA) class II or III) and intermediate (10-18 mL/kg/min) PVO2, assessed during cardiopulmonary exercise test. Mean (SD) left ventricular ejection fraction (EF) and pulmonary systolic pressure (PAP) were 41 +/- 3% and 47 +/- 14 mmHg, respectively. The enhanced ventilatory response to exercise (EVR) was assessed as a slope of the relation between minute ventilation and carbon dioxide production (VE/VCO2 slope) > 35.

RESULTS

Thirty-three over 129 patients (26%) had EVR. Mean BNP plasma level was 394 +/- 347 pg/mL. A significant correlation between BNP and EVR (r = 0.310; p < 0.01), was observed. In the logistic multivariate model, a BNP plasma level > 100 pg/mL had an independent predictive value for EVR (95% IC 1.68 to 10.5, Odds Ratio 4.23, p = 0.02). We found a significant correlation between BNP and PAP (r = 0.390; p < 0.001), and between PAP and EVR (r = 0.511; p < 0.01).

CONCLUSIONS

In CHF patients with intermediate PVO2, plasma BNP is clearly related to the enhanced ventilatory response to exercise. In this subset, BNP levels could represent an effective alternative tool for the clinical assessment in patients with unreliable cardiopulmonary exercise test.