Evaluation of Instantaneous Wave-Free Ratio and Fractional Flow Reserve in Severe Aortic Valve Stenosis.

BACKGROUND: The optimal functional evaluation of coronary artery stenosis in patients with severe aortic stenosis (AS) has not been established. The objective of the study was to evaluate the instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) in patients with and without severe AS. METHODS: We retrospectively investigated 395 lesions in 293 patients with severe AS and 2257 lesions in 1882 patients without severe AS between 2010 and 2022 from a subgroup of the Interventional Cardiology Research In-Cooperation Society FFR Registry. All patients had FFR values, and iFR was analyzed post hoc using dedicated software only in lesions with adequate resting pressure curves (311 lesions in patients with severe AS and 2257 lesions in patients with nonsevere AS). RESULTS: The incidence of iFR ≤0.89 was 66.6% and 31.8% (P<0.001), while the incidence of FFR ≤0.80 was 45.3% and 43.9% (P=0.60) in the severe AS group and the nonsevere AS group, respectively. In the severe AS group, most lesions (95.2%) with iFR >0.89 had FFR >0.80, while 36.2% of lesions with iFR ≤0.89 had FFR >0.80. During a median follow-up of 2 years, FFR ≤0.80 was significantly associated with deferred lesion failure (adjusted hazard ratio, 2.71 [95% CI, 1.08-6.80]; P=0.034), while iFR ≤0.89 showed no prognostic value (adjusted hazard ratio, 1.31 [95% CI, 0.47-3.60]; P=0.60) in the severe AS group. Lesions with iFR ≤0.89 and FFR >0.80, in particular, were not associated with a higher rate of deferred lesion failure at 3 years compared with lesions with iFR >0.89 (15.4% versus 17.0%; P=0.58). CONCLUSIONS: This study suggested that FFR appears to be less affected by the presence of severe AS and is more associated with prognosis. iFR may overestimate the functional severity of coronary artery disease without prognostic significance, yet it can be useful for excluding significant stenosis in patients with severe AS.

Surveillance Stress Testing After Percutaneous Intervention for Patients With Multivessel or Left Main Coronary Disease.

BACKGROUND: The optimal surveillance strategy after percutaneous coronary intervention (PCI) for high-risk patients with multivessel or left main coronary artery disease (CAD) remains uncertain. OBJECTIVES: This study aims to determine the prognostic role of routine functional testing in patients with multivessel or left main CAD who underwent PCI. METHODS: The POST-PCI (Pragmatic Trial Comparing Symptom-Oriented Versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention) trial randomized high-risk PCI patients to routine functional testing at 1 year or standard care alone during follow-up. This analysis focused on participants with multivessel or left main CAD. The primary outcome was a composite of death from any cause, myocardial infarction, or hospitalization for unstable angina at 2 years. RESULTS: Among 1,706 initially randomized patients, 1,192 patients with multivessel (n = 833) or left main (n = 359) were identified, with 589 in the functional testing group and 603 in the standard care group. Two-year incidences of primary outcome were similar between the functional testing group and the standard care group (6.2% vs 5.7%, respectively; HR: 1.09; 95% CI: 0.68-1.74; P = 0.73). This trend persisted in both groups of multivessel (6.2% vs 5.7%; HR: 1.09; 95% CI: 0.62-1.89; P = 0.78) and left main disease (6.2% vs 5.7%; HR: 1.09; 95% CI: 0.46-2.56; P = 0.85) (P for interaction = 0.90). Routine surveillance functional testing was associated with increased rates of invasive angiography and repeat revascularization beyond 1 year. CONCLUSIONS: In high-risk patients with multivessel or left main CAD who underwent PCI, there was no incremental clinical benefit from routine surveillance functional-testing compared with standard care alone during follow-up. (Pragmatic Trial Comparing Symptom-Oriented Versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention [POST-PCI]; NCT03217877).

Impact of Target Lesion Revascularization on Long-Term Mortality After Percutaneous Coronary Intervention for Left Main Disease.

BACKGROUND: Although target lesion revascularization (TLR) after percutaneous coronary intervention (PCI) for unprotected left main coronary artery (LMCA) disease is not rare, its timing of occurrence and prognostic impact on long-term mortality is uncertain. OBJECTIVES: This study sought to investigate TLR incidence over time and its impact on mortality after PCI with drug-eluting stents (DES) for LMCA disease. METHODS: Using a pooled data from 4 multicenter observational registries (IRIS-DES [Interventional Cardiology Research Incorporation Society-Drug-Eluting Stents], IRIS-MAIN [Interventional Cardiology Research Incorporation Society-Left MAIN Revascularization], MAIN-COMPARE [Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization], and PRECOMBAT [PREmier of Randomized COMparison of Bypass Surgery versus AngioplasTy Using Drug-Eluting Stent in Patients with Left Main Coronary Artery Disease]), we evaluated 1,397 patients with LMCA disease treated with DES and available long-term mortality data. The association between TLR and the 10-year risk of mortality was examined by multivariable Cox proportional hazards regression, with TLR as a time-varying covariate. RESULTS: During maximum follow-up of 10 years (median 6.8 years), TLR occurred in 118 patients and its 10-year cumulative incidence was 10.8%. TLR mostly occurred within 2 years after initial PCI and decreased over time: early-stage TLR (within 2 years) in 73 (61.9%) patients and late-stage TLR (beyond 2 years) in 45 (38.1%) patients. Among all TLR patients, 23 patients underwent coronary artery bypass grafting and 95 underwent repeat PCI. In the time-varying multivariable Cox model, the presence of TLR was not significantly associated with an increased risk of mortality (adjusted HR: 0.90; 95% CI: 0.50-1.63; P = 0.73). CONCLUSIONS: Although the incidence of ischemia-driven TLR was mostly common within 2 years after left main PCI, TLR occurred steadily during the 10-year follow-up period. However, given that such patients were optimally revascularized, the prognostic impact of TLR on mortality was not substantial. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133; Observational Study for Left Main Disease Treatment [IRIS-MAIN]; NCT01341327; Ten-Year Outcomes of Stents Versus Coronary-Artery Bypass Grafting for Left Main Coronary Artery Disease [MAIN COMPARE]; NCT02791412; Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT]; NCT00422968).

Short-term and long-term effects of noninvasive cardiac radioablation for ventricular tachycardia: A single-center case series.

Background: Noninvasive cardiac radioablation is reported to be effective and safe for the treatment of ventricular tachycardia (VT). Objective: This study aimed to analyze the acute and long-term effects of VT radioablation. Methods: Patients with intractable VT or premature ventricular contraction (PVC)-induced cardiomyopathy were included in this study and treated using a single-fraction 25-Gy dose of cardiac radioablation. To quantitatively analyze the acute response after treatment, continuous electrocardiography monitoring was performed from 24 hours before to 48 hours after irradiation and at the 1-month follow-up. Long-term clinical safety and efficacy were assessed 1-year follow-up. Results: From 2019 to 2020, 6 patients were treated with radioablation for ischemic VT (n = 3), nonischemic VT (n = 2), or PVC-induced cardiomyopathy (n = 1). In the short-term assessment, the total burden of ventricular beats decreased by 49% within 24 hours after radioablation and further decreased by 70% at 1 month. The VT component decreased earlier and more dramatically than the PVC component (decreased by 91% and 57% at 1 month, respectively). In the long-term assessment, 5 patients showed complete (n = 3) or partial (n = 2) remission of ventricular arrhythmias. One patient showed recurrence at 10 months, which was successfully suppressed with medical treatment. The posttreatment PVC coupling interval was prolonged (+38 ms at 1 month). Ischemic VT burden decreased more markedly than nonischemic VT burden after radioablation. Conclusion: In this small case series of 6 patients, without a comparison group, cardiac radioablation appeared to decrease the intractable VT burden. A therapeutic effect was apparent within 1-2 days after treatment but was variable by etiology of cardiomyopathy.