Comparison of Patients Undergoing Percutaneous Coronary Intervention in Contemporary U.S. Practice With ISCHEMIA Trial Population

Stable Coronary Artery Disease: Who Finally Benefits from Coronary Revascularization in the Modern Era? The ISCHEMIA and Interim ISCHEMIA-EXTEND Analysis

Coronary revascularization is one of the most studied treatment modalities in cardiology; however, there is no consensus among experts about its indications in patients with stable coronary artery disease (SCAD). Contemporary data regarding the role of revascularization in SCAD are in clear conflict with the current European guidelines. This article discusses the main statements of the most significant American and European Guidelines on myocardial revascularization of the last decade and also analyzes the appropriateness of revascularization to improve the prognosis and symptoms in SCAD in the light of new research data, primarily the ISCHEMIA study (NCT01471522) and the ACC/AHA 2021 Revascularization Guidelines based on them. Data on the revascularization in SCAD obtained after the completion of ISCHEMIA (including the interim analysis of ISCHEMIA-EXTEND) and their potential significance are discussed. The results of ISCHEMIA sub-analyses in the most important "controversial" subgroups (3-vessel disease, proximal left anterior descending artery disease, strongly positive stress test, etc.) are reviewed, as are the results of the ISCHEMIA-CKD substudy in patients with severe chronic kidney disease (CKD).

Deferred Versus Performed Revascularization for Left Main Coronary Disease With Hemodynamic Significance

BACKGROUND

The majority of randomized controlled trials of revascularization decision-making excludes left main coronary artery disease (LMD). Therefore, contemporary clinical outcomes of patients with stable coronary artery disease and LMD with proven ischemia remain poorly understood. The aim of this study was to assess the long-term clinical outcomes of physiologically significant LMD according to the treatment strategies of revascularization versus revascularization deferral.

METHODS

In this international multicenter registry of stable LMD interrogated with the instantaneous wave-free ratio, patients with physiologically significant ischemia (instantaneous wave-free ratio ≤0.89) were analyzed according to the coronary revascularization (n=151) versus revascularization deferral (n=74). Propensity score matching was performed to adjust for baseline clinical characteristics. The primary end point was a composite of death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization of left main stem. The secondary end points were as follows: cardiac death or spontaneous LMD-related myocardial infarction; and ischemia-driven target lesion revascularization of left main stem.

RESULTS

At a median follow-up period of 2.8 years, the primary end point occurred in 11 patients (14.9%) in the revascularized group and 21 patients (28.4%) in the deferred group (hazard ratio, 0.42 [95% CI, 0.20-0.89]; P=0.023). For the secondary end points, cardiac death or LMD-related myocardial infarction occurred significantly less frequently in the revascularized group (0.0% versus 8.1%; P=0.004). The rate of ischemia-driven target lesion revascularization of left main stem was also significantly lower in the revascularized group (5.4% versus 17.6%; hazard ratio, 0.20 [95% CI, 0.056-0.70]; P=0.012).

CONCLUSIONS

In patients who underwent revascularization for stable coronary artery disease and physiologically significant LMD determined by instantaneous wave-free ratio, the long-term clinical outcomes were significantly improved as compared with those in whom revascularization was deferred.

Trends and Real-World Safety of Patients Undergoing Percutaneous Coronary Intervention for Symptomatic Stable Ischaemic Heart Disease in Australia

BACKGROUND

Percutaneous coronary intervention (PCI) in stable ischaemic heart disease (SIHD) has not been shown to improve prognosis but can alleviate symptoms and improve quality of life. Appropriately selected patients with symptoms refractory to medical therapy therefore stand to benefit, provided safety is proven.

METHODS

Consecutive patients undergoing PCI for SIHD between 2005-2018 in a prospective registry were included. Yearly comparisons evaluated trends, and a sub-analysis was performed comparing proximal left anterior descending artery (prox-LAD) to other-than-proximal LAD (non-pLAD) PCI. Outcomes included peri-procedural characteristics, in-hospital and 30-day event rates including MACE, and 5-year National Death Index (NDI) linked mortality.

RESULTS

There were 9,421 procedures included. Over time, patients were increasingly co-morbid and had higher rates of AHA/ACC class B2/C lesions, ostial stenoses, bifurcation lesions, and chronic total occlusions (all p-for-trend ≤0.001). Over 14 years, major bleeding reduced (1.05% in 2005/06 vs 0.29% in 2017/18, p-for-trend <0.001), while other in-hospital and 30-day event rates were stably low. There were only seven (0.07%) in hospital deaths and 5-year mortality was 10.3%. No differences were found in outcomes between patients who underwent prox-LAD compared to non-pLAD PCI. Major independent predictors of NDI linked all-cause mortality included an eGFR <30 mL/min/1.73 m² (HR 4.06, 95% CI 3.26-5.06), chronic obstructive pulmonary disease (COPD) (HR 2.25, 95% CI 1.89-2.67) and LVEF <30% (HR 2.13, 95% CI 1.57-2.89).

CONCLUSIONS

Although patient and procedural complexity increased over time, a high degree of procedural success and safety was maintained, including in those undergoing prox-LAD PCI. These real-world data can enhance shared decision making discussions regarding whether PCI should be pursued in patients with symptomatic SIHD refractory to medical therapy.

Ischemia Trial: Does the Cardiology Community Need to Pivot or Continue Current Practices?

PURPOSE OF REVIEW

For decades, the standard of care for stable ischemic heart disease (SIHD) has been an ischemia-centric approach based on largely observational data suggesting a survival benefit of revascularization in patients with moderate-or-severe ischemia. In this article, we will objectively review the evolution of the ischemia paradigm, the trial evidence comparing revascularization to medical therapy in SIHD, and what contemporary practice should be in 2022.

RECENT FINDINGS

Randomized trials, including COURAGE and, most recently, the ISCHEMIA trial, have shown no reduction in "hard outcomes" like death and myocardial infarction (MI) in SIHD compared to medical therapy. The trial excluded high-risk patients with left main disease, low ejection fraction (EF) < 35%, and severe unacceptable angina. Irrespective of the severity of ischemia and the extent of coronary artery disease (CAD), revascularization did not offer any prognostic advantage over medical therapy. On the other hand, there was a durable improvement in symptoms. While there are many caveats to the ISCHEMIA trial, the overall strengths of the trial outweigh these limitations. The findings of ISCHEMIA are consistent with previous trials. It is time for the cardiology community to pivot towards medical therapy as the initial step for most patients with SIHD. Physicians should have the "COURAGE" to embrace "ISCHEMIA" and be comfortable with treating ischemia medically.

Does the ISCHEMIA Trial Apply to My Patients?

PURPOSE OF REVIEW

The ISCHEMIA trial demonstrated no difference in myocardial infarction or death in patients with stable coronary disease and moderate or large ischemia territory treated either with invasive revascularization or optimal medical therapy. Whether the findings of the randomized control trial relates to real-world outcomes is uncertain.

RECENT FINDINGS

Contemporary guideline-directed medical therapy has had a significant impact on the prognosis of coronary artery disease. Various observational data appear to indicate limited generalizability of the ISCHEMIA trial in different populations. Further studies are warranted to evaluate the optimal modality of therapy in patients with stable coronary disease and moderate or severe ischemia. The applicability of ISCHEMIA and ISCHEMIA-CKD trials still requires further validation.