Early invasive coronary angiography and acute ischaemic heart failure outcomes

Coronary Assessment in Heart Failure within a Safety-Net Setting: Disparities and Outcomes

Background

Though ischemic cardiomyopathy is the leading cause of heart failure (HF), most patients do not undergo coronary assessment after heart failure diagnosis. In a safety-net population, referral patterns have not been studied, and it is unknown whether coronary assessment is associated with improved HF outcomes.

Methods

Using an electronic health record cohort of all individuals with HF within San Francisco Health Network from 2001-2019, we identified factors associated with completion of coronary assessment (invasive coronary angiography, nuclear stress, or coronary computed tomographic angiography). Then we emulated a randomized clinical trial of elective coronary assessment with outcomes of all-cause mortality and a composite outcome of mortality and emergent angiography. We used propensity scores to account for differences between groups. We used national death records to improve ascertainment of mortality.

Results

Among 14,829 individuals with HF (median 62 years old, 5,855 [40%] women), 3,987 (26.9%) ever completed coronary assessment, with 2,467 (18.5%) assessed out of 13,301 with unknown CAD status at HF diagnosis. Women and older individuals were less likely to complete coronary assessment, with differences by race/ethnicity, medical history, substance use, housing, and echocardiographic findings. Among 5,972 eligible for inclusion in the "target trial," 627 underwent early elective coronary assessment and 5,345 did not. Coronary assessment was associated with lower mortality (HR 0.84; 95% CI 0.72-0.97; p=0.025), reduced risk of the composite outcome, higher rates of revascularization, and higher use of medical therapy.

Conclusions

In a safety-net population, disparities in coronary assessment after HF diagnosis are not fully explained by CAD risk factors. Our target trial emulation suggests coronary assessment is associated with improved HF outcomes possibly related to higher rates of revascularization and GDMT use, but with low certainty that this is finding is not attributable to unmeasured confounding.

Real-World Examination of Revascularization Strategies for Left Main Coronary Disease in Ontario, Canada

BACKGROUND

Randomized trials have compared percutaneous coronary intervention and coronary artery bypass grafting (CABG) in patients with left main coronary artery disease undergoing nonemergent revascularization. However, there is a paucity of real-world contemporary observational studies comparing percutaneous coronary intervention (PCI) and CABG.

OBJECTIVES

The purpose of this study was to compare the long-term clinical outcomes of CABG versus PCI in patients with left main coronary disease.

METHODS

Clinical and administrative databases for Ontario, Canada, were linked to obtain records of all patients with angiographic evidence of left main coronary artery disease (≥50% stenosis) treated with either isolated CABG or PCI from 2008 to 2020. Emergent, cardiogenic shock, and ST-segment elevation myocardial infarction patients were excluded. Baseline characteristics of patients were compared and 1:1 propensity score matching was performed. Late mortality and major adverse cardiac and cerebrovascular events were compared between the matched groups using a Cox proportional hazard model.

RESULTS

After exclusions, 1,299 and 21,287 patients underwent PCI and CABG, respectively. Prior to matching, PCI patients were older (age 75.2 vs 68.0 years) and more likely to be women (34.6% vs 20.1%), although they had less CAD burden. Propensity score matching on 25 baseline covariates yielded 1,128 well-matched pairs. There was no difference in early mortality between PCI and CABG (5.5% vs 3.9%; P = 0.075). Over 7-year follow-up, all-cause mortality (53.6% vs 35.2%; HR: 1.63; 95% CI: 1.42-1.87; P < 0.001) and major adverse cardiac and cerebrovascular events (66.8% vs 48.6%; HR: 1.77; 95% CI: 1.57-2.00) were significantly higher with PCI than CABG.

CONCLUSIONS

CABG was the most common revascularization strategy in this real-world registry. Patients undergoing PCI were much older and of higher risk at baseline. After matching, there was no difference in early mortality but improved late survival and freedom from major adverse cardiac and cerebrovascular events with CABG.

Is it the Time to Move Towards Coronary Computed Tomography Angiography-Derived Fractional Flow Reserve Guided Percutaneous Coronary Intervention? The Pros and Cons

Coronary artery disease is the leading cause of mortality worldwide. Diagnosis is conventionally performed by direct visualization of the arteries by invasive coronary angiography (ICA), which has inherent limitations and risks. Measurement of fractional flow reserve (FFR) has been suggested for a more accurate assessment of ischemia in the coronary artery with high accuracy for determining the severity and decision on the necessity of intervention. Nevertheless, invasive coronary angiography-derived fractional flow reserve (ICA-FFR) is currently used in less than one-third of clinical practices because of the invasive nature of ICA and the need for additional equipment and experience, as well as the cost and extra time needed for the procedure. Recent technical advances have moved towards non-invasive high-quality imaging modalities, such as magnetic resonance, single-photon emission computed tomography, and coronary computed tomography (CT) scan; however, none had a definitive modality to confirm hemodynamically significant coronary artery stenosis. Coronary computed tomography angiography (CCTA) can provide accurate anatomic and hemodynamic data about the coronary lesion, especially calculating fractional flow reserve derived from CCTA (CCTA-FFR). Although growing evidence has been published regarding CCTA-FFR results being comparable to ICA-FFR, CCTA-FFR has not yet replaced the invasive conventional angiography, pending additional studies to validate the advantages and disadvantages of each diagnostic method. Furthermore, it has to be identified whether revascularization of a stenotic lesion is plausible based on CCTA-FFR and if the therapeutic plan can be determined safely and accurately without confirmation from invasive methods. Therefore, in the present review, we will outline the pros and cons of using CCTA-FFR vs. ICA-FFR regarding diagnostic accuracy and treatment decision-making.

Estimation of the Absolute Risk of Cardiovascular Disease and Other Events: Issues With the Use of Multiple Fine-Gray Subdistribution Hazard Models

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Background:

The Fine-Gray subdistribution hazard model is frequently used in the cardiovascular literature to estimate subject-specific probabilities of the occurrence of an event of interest over time in the presence of competing risks. A little-known limitation of this approach is that, for some subjects and for some time points, the sum of the subject-specific probabilities for the different event types (eg, cardiovascular and noncardiovascular death) can exceed one.

Methods:

We used data on 8238 patients hospitalized with congestive heart failure in Ontario, Canada. We fit 2 Fine-Gray subdistribution hazards models, one for cardiovascular death and one for noncardiovascular death and estimated the probability of death due to each cause within 5 years of hospital admission. We also fit 2 cause-specific hazard models for the 2 event types and combined the estimated cause-specific hazard functions to obtain subject-specific estimates of the probabilities of each of the 2 event types occurring within 5 years.

Results:

When adding the probabilities of 5-year cardiovascular death and 5-year noncardiovascular death obtained from the Fine-Gray subdistribution hazard models, 8.6% of subjects had an estimated probability of 5-year all-cause mortality that exceeded 1 (100%). This problem was avoided by fitting 2 cause-specific hazard models, one for each outcome type, and combining the estimated cause-specific hazard functions to obtain subject-specific estimates of the risk of cardiovascular and noncardiovascular death.

Conclusions:

The Fine-Gray subdistribution hazard model may be problematic to use for a comprehensive assessment of absolute risks of multiple outcomes, while the combination of 2 cause-specific hazard models shows better statistical behaviour. Cause-specific modeling should not be discarded in competing risk situations.