Successful double-layer metal stents rotational ablation under 2-dimensional and 3-dimensional optical coherence tomography guidance: a case report.

BACKGROUND: Stent ablation with rotational atherectomy has been considered a bail-out strategy for the treatment of severe stent underexpansion. Only a few reports have yet shown rotational ablation for double-layer metal struts. CASE PRESENTATION: We present a case of 80-year-old female patient presented to our hospital because of worsening effort angina. Coronary angiography revealed severe in-stent restenosis in the proximal left anterior descending artery. Optical coherence tomography (OCT) examinations found that severe stenosis occurred at the overlap region with 2-layer underexpanded stents and circumferential calcification beneath them. Under the guidance of 2-dimensional (2D) and 3-dimensional (3D) OCT, we successfully performed percutaneous coronary intervention (PCI) of this lesion after adequate stent ablation, high-pressure balloon dilatation, and subsequent everolimus-eluting stent implantation. The patient recovered well uneventfully and discharged from hospital 7 days later. No restenosis occurred after 12 months. CONCLUSIONS: We report a very rare case of in-stent restenosis due to double-layer underexpanded stents. The entire percutaneous coronary intervention procedure was performed step by step under the guidance of high-resolution OCT. Our findings highlight the specific value of 2D and 3D OCT guidance in double-layer stents rotational ablation.

Association of Quantitative Flow Ratio with Lesion Severity and Its Ability to Discriminate Myocardial Ischemia

Background and Objectives@#Quantitative flow ratio (QFR) is an angiography-based technique for functional assessment of coronary artery stenosis. This study investigated the response of QFR to different degree of stenosis severity and its ability to predict the positron emission tomography (PET)-defined myocardial ischemia. @*Methods@#From 109 patients with 185 vessels who underwent both 13 N-ammonia PET and invasive physiological measurement, we compared QFR, fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) for the responses to the different degree of anatomical (percent diameter stenosis [%DS]) and hemodynamic (relative flow reserve [RFR], coronary flow reserve, hyperemic stenosis resistance, and stress myocardial flow) stenosis severity and diagnostic performance against PET-derived parameters. @*Results@#QFR, FFR, and iFR showed similar responses to both anatomic and hemodynamic stenosis severity. Regarding RFR, the diagnostic accuracy of QFR was lower than FFR (76.2% vs. 83.2%, p=0.021) and iFR (76.2% vs. 84.3%, p=0.031). For coronary flow capacity (CFC), QFR showed a lower accuracy than iFR (74.1% vs. 82%, p=0.031) and lower discriminant function than FFR (area under curve: 0.74 vs. 0.79, p=0.044). Discordance between QFR and FFR or iFR was shown in 14.6% of cases and was driven by the difference in %DS and heterogeneous distribution of PET-derived RFR and stress myocardial blood flow. @*Conclusions@#QFR demonstrated a similar response to different anatomic and hemodynamic stenosis severity as FFR or iFR. However, its diagnostic performance was inferior to FFR and iFR when PET-derived RFR and CFC were used as a reference.

Association of Quantitative Flow Ratio with Lesion Severity and Its Ability to Discriminate Myocardial Ischemia

Background and Objectives@#Quantitative flow ratio (QFR) is an angiography-based technique for functional assessment of coronary artery stenosis. This study investigated the response of QFR to different degree of stenosis severity and its ability to predict the positron emission tomography (PET)-defined myocardial ischemia. @*Methods@#From 109 patients with 185 vessels who underwent both 13 N-ammonia PET and invasive physiological measurement, we compared QFR, fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) for the responses to the different degree of anatomical (percent diameter stenosis [%DS]) and hemodynamic (relative flow reserve [RFR], coronary flow reserve, hyperemic stenosis resistance, and stress myocardial flow) stenosis severity and diagnostic performance against PET-derived parameters. @*Results@#QFR, FFR, and iFR showed similar responses to both anatomic and hemodynamic stenosis severity. Regarding RFR, the diagnostic accuracy of QFR was lower than FFR (76.2% vs. 83.2%, p=0.021) and iFR (76.2% vs. 84.3%, p=0.031). For coronary flow capacity (CFC), QFR showed a lower accuracy than iFR (74.1% vs. 82%, p=0.031) and lower discriminant function than FFR (area under curve: 0.74 vs. 0.79, p=0.044). Discordance between QFR and FFR or iFR was shown in 14.6% of cases and was driven by the difference in %DS and heterogeneous distribution of PET-derived RFR and stress myocardial blood flow. @*Conclusions@#QFR demonstrated a similar response to different anatomic and hemodynamic stenosis severity as FFR or iFR. However, its diagnostic performance was inferior to FFR and iFR when PET-derived RFR and CFC were used as a reference.

Clinical Relevance of 18F-Sodium Fluoride Positron-Emission Tomography in Noninvasive Identification of High-Risk Plaque in Patients With Coronary Artery Disease.

BACKGROUND: 18F-sodium fluoride (18F-NaF) positron-emission tomography has been introduced as a potential noninvasive imaging tool to identify plaques with high-risk characteristics in patients with coronary artery disease. We sought to evaluate the clinical relevance of 18F-NaF uptake using optical coherence tomography (OCT), intravascular ultrasound (IVUS), and coronary computed tomography angiography in patients with coronary artery disease. METHODS AND RESULTS: The target population consisted of 51 prospectively enrolled patients (93 stenoses) who underwent 18F-NaF positron-emission tomography before invasive coronary angiography. 18F-NaF uptake was compared with IVUS- and OCT-derived plaque characteristics. In the coronary computed tomography angiography subgroup (46 lesions), qualitative lesion characteristics were compared between 18F-NaF-positive and 18F-NaF-negative plaques using adverse plaque characteristics. The plaques with 18F-NaF uptake showed significantly higher plaque burden, more frequent posterior attenuation and positive remodeling in IVUS, and significantly higher maximum lipid arc and more frequent microvessels in OCT (all P<0.05). There were no differences in minimum lumen area and area of calcium between 18F-NaF-positive and 18F-NaF-negative lesions. Among 51 lesions with 18F-NaF-positive uptake, 48 lesions (94.1%) had at least one of high-risk characteristics. The 18F-NaF tissue-to-background ratio in plaques with high-risk characteristics was significantly higher than in those without (1.09 [95% confidence interval, 0.85-1.34] versus 0.62 [95% confidence interval, 0.42-0.82], P<0.001 for IVUS definition; 0.76 [95% confidence interval, 0.54-0.98] versus 0.42 [95% confidence interval, 0.21-0.62], P=0.014 for OCT definition). Among the 15 lesions that met both IVUS- and OCT-defined criteria for high-risk plaque, 14 (93.3%) showed 18F-NaF-positive uptake. There was no difference in the prevalence of plaques with any adverse plaque characteristics between 18F-NaF-positive and 18F-NaF-negative plaques in the coronary computed tomography angiography subgroup (85.2% versus 78.9%; P=0.583). CONCLUSIONS: This study's results suggest that 18F-NaF positron-emission tomography can be a useful noninvasive diagnostic tool to identify and localize plaque with high-risk characteristics. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02388412.

A confused ECG with multiple rhythms caused by atrial premature contractions: A case report.

INTRODUCTION: Atrial premature contractions (APCs) are commonly encountered in clinical practice. The APCs may influence heart conduction system and induce other arrhythmia. The disorder of atrioventricular conduction is related to electrophysiological phenomena, difficult to understand and diagnose. CASE REPORT: We presented a 15-year-old male patient whose baseline electrocardiogram (ECG) was confused with multiple rhythms. Electrophysiological study results showed sinus rhythm with nonconducted APCs in bigeminal rhythm. Nonconducted APCs were blocked without H wave. Some APCs conducted to ventricle with longer AH interval and HV interval. When APCs were abolished by radiofrequency ablation, this patient was free from any arrhythmia during follow-up. CONCLUSION: We considered that the basic rhythm of the baseline ECG was sinus rhythm with atrial bigeminy rhythm and narrow QRS extrasystoles (junctional); some APCs were blocked and some APCs conducted to ventricle with aberrant QRS complexes. The phenomenon of baseline ECG was caused by the APCs.