Functional Angioplasty: Definitions, Historical Overview, and Future Perspectives

Percutaneous coronary intervention (PCI) is used to treat obstructive coronary artery disease (CAD). The role of PCI is well defined in acute coronary syndrome, but that for stable CAD remains debatable. Although PCI generally relieves angina in patients with stable CAD, it may not change its prognosis. The extent and severity of CAD are major determinants of prognosis, and complete revascularization (CR) of all ischemia-causing lesions might improve outcomes. Several studies have shown better outcomes with CR than with incomplete revascularization, emphasizing the importance of functional angioplasty. However, different definitions of inducible myocardial ischemia have been used across studies, making their comparison difficult. Various diagnostic tools have been used to estimate the presence, extent, and severity of inducible myocardial ischemia. However, to date, there are no agreed reference standards of inducible myocardial ischemia. The hallmarks of inducible myocardial ischemia such as electrocardiographic changes and regional wall motion abnormalities may be more clinically relevant as the reference standard to define ischemia-causing lesions. In this review, we summarize studies regarding myocardial ischemia, PCI guidance, and possible explanations for similar findings across studies. Also, we provide some insights into the ideal definition of inducible myocardial ischemia and highlight the appropriate PCI strategy.

SYNTAX Score and SYNTAX Score II Can Predict the Clinical Outcomes of Patients with Left Main and/or 3-Vessel Disease Undergoing Percutaneous Coronary Intervention in the Contemporary Cobalt-Chromium Everolimus-Eluting Stent Era

BACKGROUND AND OBJECTIVES@#The impact of SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery score (SS) and SS II in patients who receive percutaneous coronary intervention with second-generation everolimus-eluting stents (EES) has not been fully validated.@*METHODS@#The SS, SS II were calculated in 1,248 patients with left main and/or 3-vessel disease treated with EES. Patient-oriented composite endpoint (POCE; all-cause death, any myocardial infarction (MI), any revascularization) and target lesion failure (TLF: cardiac death, target-vessel MI, target lesion revascularization) were analyzed.@*RESULTS@#The mean SS was 21.1±9.6. Three-year POCE increased according to the SS group (15.2% vs. 19.9% vs. 27.4% for low (≤22), intermediate (≥23, ≤32), high (≥33) SS groups, p<0.001). By multivariate Cox proportional hazard analysis, SS group was an independent predictor of 3-year POCE (hazard ratio, 1.324; 95% confidence interval, 1.095–1.601; p=0.004). The receiver operating characteristic curves revealed that the SS II was superior to the SS for 3-year POCE prediction (area under the curve [AUC]: 0.611 vs. 0.669 for SS vs. SS II, p=0.019), but not for 3-year TLF (AUC: 0.631 vs. 0.660 for SS vs. SS II, p=0.996). In subgroup analysis, SS II was superior to SS in patients with cardiovascular clinical risk factors, and in those presenting as stable angina.@*CONCLUSIONS@#The usefulness of SS and SS II was still valid in patients with left main and/or 3-vessel disease. SS II was superior to SS for the prediction of patient-oriented outcomes, but not for lesion-oriented outcomes.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00698607ClinicalTrials.gov Identifier: NCT01605721

Sinus of Valsalva Thrombosis Detected on Computed Tomography after Transcatheter Aortic Valve Replacement

Background and Objectives@#Leaflet thrombosis after transcatheter aortic valve replacement (TAVR) has been reported recently, whereas thrombus formation in sinus of Valsalva has yet to be fully evaluated. This study describes clinical and cardiac computed tomography (CT) findings of patients with sinus of Valsalva thrombosis. @*Methods@#Between March 2011 and Aug 2019, 192 patients underwent cardiac CT after TAVR. After a retrospective review of CT images, 9 patients (82 years, male:female=2:7) who had sinus of Valsalva thrombosis identified by cardiac CT were selected for this study. Patient demographics, interval between TAVR and cardiac CT scan, location and CT attenuation of sinus of Valsalva thrombosis, and presence of concurrent leaflet thrombosis were evaluated. @*Results@#The median interval between TAVR and cardiac CT was 11 days. Sinus of Valsalva thrombosis was frequently detected in the non-coronary sinus (89%, 8/9), and predominantly located in the bottom of the sinus extending upward towards the sinotubular junction. Three patients had concomitant leaflet thrombosis, and 3 patients had subclinical embolic stroke noted on brain magnetic resonance imaging. All patients had been prescribed aspirin and clopidogrel after TAVR for at least 6 months without anticoagulants. @*Conclusions@#Cardiac CT after TAVR can detect sinus of Valsalva thrombosis, and attention should be paid to this potential source of subsequent systemic embolization.

SYNTAX Score and SYNTAX Score II Can Predict the Clinical Outcomes of Patients with Left Main and/or 3-Vessel Disease Undergoing Percutaneous Coronary Intervention in the Contemporary Cobalt-Chromium Everolimus-Eluting Stent Era

BACKGROUND AND OBJECTIVES: The impact of SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery score (SS) and SS II in patients who receive percutaneous coronary intervention with second-generation everolimus-eluting stents (EES) has not been fully validated.METHODS: The SS, SS II were calculated in 1,248 patients with left main and/or 3-vessel disease treated with EES. Patient-oriented composite endpoint (POCE; all-cause death, any myocardial infarction (MI), any revascularization) and target lesion failure (TLF: cardiac death, target-vessel MI, target lesion revascularization) were analyzed.RESULTS: The mean SS was 21.1±9.6. Three-year POCE increased according to the SS group (15.2% vs. 19.9% vs. 27.4% for low (≤22), intermediate (≥23, ≤32), high (≥33) SS groups, p<0.001). By multivariate Cox proportional hazard analysis, SS group was an independent predictor of 3-year POCE (hazard ratio, 1.324; 95% confidence interval, 1.095–1.601; p=0.004). The receiver operating characteristic curves revealed that the SS II was superior to the SS for 3-year POCE prediction (area under the curve [AUC]: 0.611 vs. 0.669 for SS vs. SS II, p=0.019), but not for 3-year TLF (AUC: 0.631 vs. 0.660 for SS vs. SS II, p=0.996). In subgroup analysis, SS II was superior to SS in patients with cardiovascular clinical risk factors, and in those presenting as stable angina.CONCLUSIONS: The usefulness of SS and SS II was still valid in patients with left main and/or 3-vessel disease. SS II was superior to SS for the prediction of patient-oriented outcomes, but not for lesion-oriented outcomes.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00698607ClinicalTrials.gov Identifier: NCT01605721

Early experience and favorable clinical outcomes of everolimus-eluting bioresorbable scaffolds for coronary artery disease in Korea

BACKGROUND/AIMS: Compared with metallic drug-eluting stents (DES), bioresorbable vascular scaffolds (BVS) may further improve long-term outcomes of percutaneous coronary intervention (PCI) in patients with coronary artery disease. We report our early experience with BVS in Korea. METHODS: We evaluated 105 consecutive patients with BVS implanted at Asan Medical Center, Korea between October 21, 2015 and June 3, 2016. Angiographic results, and in-hospital and 6-month clinical outcomes were assessed. RESULTS: A total of 134 BVS were implanted to treat 115 lesions. The mean age was 62 ± 10.5 years; 85 patients (81%) were males, 26 patients (25%) were presented with acute coronary syndrome. Among 115 lesions treated with BVS, 76 (66.1%) were B2/C type, 27 (23.5%) were bifurcation lesions, and four (3.5%) were chronic total occlusion. Pre-dilation and post-dilation using high-pressure non-compliant balloon was performed in 104 lesions (90.4%) and 113 lesions (98.2%), respectively. During the procedure, intravascular imaging was used for all patients (100%; intravascular ultrasound 89 and optical coherence tomography 40 patients). Device success rate was 100%. In-segment and in-scaffold acute again were 1.1 ± 0.6 and 1.3 ± 0.5 mm, respectively. Periprocedural myocardial infraction occurred in four patients (3.8%). No deaths, stent thrombosis, or urgent revascularizations occurred either during hospitalization or the follow-up period. CONCLUSIONS: In this single-center experience, implantation of BVS with intravascular imaging support was feasible and early clinical outcomes were excellent. Evaluation of long-term efficacy and safety of BVS and its feasibility in clinical use for a broader range of lesions is warranted.

Transseptal Transcatheter Mitral Valve-in-valve Replacement for a Failed Bioprosthetic Mitral Valve

No abstract available.

Bioresorbable Vascular Scaffold Korean Expert Panel Report

Bioresorbable vascular scaffold (BRS) is an innovative device that provides structural support and drug release to prevent early recoil or restenosis, and then degrades into nontoxic compounds to avoid late complications related with metallic drug-eluting stents (DESs). BRS has several putative advantages. However, recent randomized trials and registry studies raised clinical concerns about the safety and efficacy of first generation BRS. In addition, the general guidance for the optimal practice with BRS has not been suggested due to limited long-term clinical data in Korea. To address the safety and efficacy of BRS, we reviewed the clinical evidence of BRS implantation, and suggested the appropriate criteria for patient and lesion selection, scaffold implantation technique, and management.

Early Parasympathetic Reinnervation Is Not Related to Reconnection of Major Branches of the Vagus Nerve after Heart Transplantation

BACKGROUND AND OBJECTIVES: Bicaval heart transplantation (HTx) may promote parasympathetic reinnervation. However, the prevalence and timing of reinnervation have not been fully investigated. Heart rate variability (HRV) and direct vagal stimulation were used to evaluate the presence of parasympathetic reinnervation after bicaval HTx. SUBJECTS AND METHODS: A total of 21 patients (time after HTx 0.52-4.41 years, mean 1.8±1.2 years) who received a bicaval HTx was enrolled. Reinnervation was evaluated using HRV values from 24-hour Holter recordings. A cross-sectional analysis of the HRV at 0.5-1, 1-2, and >2 years after HTx was performed. We also applied high-frequency electrical stimulation (16.7 Hz, 1 msec pulse width, ≤10 V) to the cardiac branches of the vagus nerve at the level of the superior vena cava in eight patients at 6 and 12 months after HTx. RESULTS: The degree of parasympathetic reinnervation corresponded to the time after HTx. The HRV analysis revealed that the root mean square of the successive differences between consecutive RR-intervals (RMSSD) and high-frequency power were significantly higher during the late period (>2 years) compared with the early period (0.5-1 year) after HTx. None of the eight patients who underwent direct vagal stimulation responded during the stimulation at 6 and 12 months, whereas incremental trends in HRV parameters were observed, which indicated that parasympathetic reinnervation began within 1 year after HTx. CONCLUSION: Parasympathetic reinnervation seemed to begin in the early period (<1 year) after bicaval HTx. Reconnection of major branches of the vagus nerve may not be related to early reinnervation.

Cardiac Resynchronization Therapy and QRS Duration: Systematic Review, Meta-analysis, and Meta-regression

Cardiac resynchronization therapy (CRT) has been shown to reduce the risk of death and hospitalization in patients with advanced heart failure with left ventricular dysfunction. However, controversy remains regarding who would most benefit from CRT. We performed a meta-analysis, and meta-regression in an attempt to identify factors that determine the outcome after CRT. A total of 23 trials comprising 10,103 patients were selected for this meta-analysis. Our analysis revealed that CRT significantly reduced the risk of all-cause mortality and hospitalization for heart failure compared to control treatment. The odds ratio (OR) of all-cause death had a linear relationship with mean QRS duration (P=0.009). The benefit in survival was confined to patients with a QRS duration > or =145 ms (OR, 0.86; 95% CI, 0.74-0.99), while no benefit was shown among patients with a QRS duration of 130 ms (OR, 1.00; 95% CI, 0.80-1.25) or less. Hospitalization for heart failure was shown to be significantly reduced in patients with a QRS duration > or =127 ms (OR, 0.77; 95% CI, 0.60-0.98). This meta-regression analysis implies that patients with a QRS duration > or =150 ms would most benefit from CRT, and in those with a QRS duration <130 ms CRT implantation may be potentially harmful.

Prognostic Implication of QRS Variability during Hospitalization in Patients with Acute Decompensated Heart Failure

BACKGROUND AND OBJECTIVES: Heart failure (HF) patients display more varied QRS duration. We investigated whether QRS variability during hospitalization for acute decompensated HF is associated with poor clinical outcomes after discharge. SUBJECTS AND METHODS: One hundred seventy three patients (64% males; age 60+/-13 years) admitted for acute decompensated HF with severe left ventricular (LV) dysfunction (LV ejection fraction < or =35%) were consecutively enrolled. QRS variability was calculated by the difference between maximum and minimum QRS duration acquired during hospitalization. The prognostic implications on composite endpoints of death or urgent heart transplantation were analyzed. RESULTS: Forty-two patients (24.3%) died and three patients (1.7%) underwent urgent heart transplantation during the follow-up of 51+/-18 months. Patients who reached composite endpoints (n=45) showed greater QRS variability than those who did not (n=128) (20+/-23 ms vs. 14+/-14 ms, p=0.046). Patients who had high QRS variability (more than 22 ms; n=36) tended to have a higher event rate than those with QRS variability <22 ms {39% vs. 23%, hazard ratio (HR), 1.88; 95% confidence interval (CI) 1.001-3.539, p=0.05}. Adjusting with other variables, high QRS variability was an independent predictor for composite outcome (HR 1.94; 95% CI 1.023-3.683, p=0.042). CONCLUSION: QRS variability measured during hospitalization for acute decompensated HF has a prognostic impact in HF patients with severe LV dysfunction.

Recurrent Syncope Triggered by Temporal Lobe Epilepsy: Ictal Bradycardia Syndrome

Ictal asystole is potentially lethal, and known to originate from the involvement of limbic autonomic regions. Appropriate treatment must include an antiepileptic drug and the implantation of a pacemaker. We report the case of a 54-year-old male with recurrent syncope secondary to ictal asystole triggered by temporal lobe epilepsy. This was confirmed by combined Holter and video-electroencephalogram monitoring.

Lack of Association Between Low Density Lipoprotein Particle Size and On-Treatment Platelet Reactivity in Patients With Coronary Artery Disease

BACKGROUND AND OBJECTIVES: Small dense low density lipoproteins (sd-LDL) are a risk factor for coronary artery disease and are known to stimulate platelet function in vitro. This study aimed to evaluate whether high proportion of sd-LDL is associated with high on-treatment platelet reactivity (HOPR). SUBJECTS AND METHODS: From January 2009 to March 2010, 439 subjects (mean age: 64.3+/-9.7, Male : Female=306 : 133) were enrolled from the low density LIPOProtein-cholesterol Size measurement Registry with coronary artery disease, who had undergone elective percutaneous coronary intervention and measured both LDL particle size and on-treatment platelet reactivity (OPR). Mean LDL particle size was measured by gradient gel electrophoresis (Quantimetrix, Lipoprint(TM)) and OPR by the VerifyNow(TM) system (aspirin and P2Y12). RESULTS: Between pattern A (large, buoyant LDL dominant) and B (sd-LDL dominant) population, there were no significant difference in OPR to aspirin (441.3+/-71.9 vs. 434.07+/-63.45 aspirin reaction units, p=0.351) or clopidogrel (237.9+/-87.3 vs. 244.9+/-80.7 P2Y12 reaction units, p=0.465). There was no difference in LDL particle size between patients with HOPR compared with non-HOPR patients (aspirin: 26.8+/-0.5 vs. 26.7+/-0.6 nm, p=0.078, clopidogrel: 26.7+/-0.6 vs. 26.8+/-0.5 nm, p=0.857). Pearson's correlation coefficients between LDL particle size and platelet reactivity were not statistically significant (aspirin assay: r=0.080, p=0.098, P2Y12 assay: r=-0.027, p=0.568). CONCLUSION: There was no significant association between LDL particle size and OPR in patients with coronary artery disease.

The Relevance of the Primary Prevention Criteria for Implantable Cardioverter Defibrillator Implantation in Korean Symptomatic Severe Heart Failure Patients

BACKGROUND AND OBJECTIVES: Implantable cardioverter defibrillator (ICD) therapy is recommended as the primary tool for prevention of sudden cardiac death (SCD) in symptomatic patients with severe left ventricular dysfunction. There is a paucity of information on whether this recommendation is appropriate for the Korean population with severe heart failure. SUBJECTS AND METHODS: The study group consisted of 275 consecutive patients (mean age 65 years, 71% male) who met the ICD implantation criteria for primary prevention (left ventricular ejection fraction 0.05). All-cause mortality and the incidence of SCD in the NICMP group were comparable to those of the DEFINITE standard therapy group (13% vs. 17%, 6% vs. 6%, respectively, all p>0.05). CONCLUSION: Korean patients with severe heart failure in both the ICMP and NICMP groups had all-caused mortality and risk of SCD comparable to patients in the MADIT-II and DEFINITE standard therapy groups. Therefore, the primary prevention criteria for ICD implantation would be appropriate in both Korean ICMP and NICMP patients.

Chronic Kidney Disease as an Independent Risk Factor for Thromboembolism in Patients with Atrial Fibrillation / 대한내과학회지

BACKGROUND/AIMS: The CHADS2 scoring system has been widely used to stratify thromboembolic risk associated with atrial fibrillation. Chronic kidney disease (CKD) is associated with increased risk of stroke in patients with atrial fibrillation (AF) but has not yet been included in risk-scoring systems. We analyzed the difference in thromboembolic risk of patients with AF and a moderate risk of stroke according to the presence of CKD. METHODS: Of 1,952 patients with AF, 451 with a CHADS2 score of 1 were divided into two groups according to the presence of CKD, and thromboembolic events were analyzed. Each group was further classified by the antithrombotic regimen used: warfarin or aspirin. RESULTS: Of the 451 patients, 94 with CKD had a significantly higher risk for thromboembolic complications than the 357 patients without CKD (hazard ratio [HR], 3.630; 95% confidence interval [CI], 1.565-8.422; p = 0.003). Patients with CKD who were on aspirin had a higher risk for thromboembolic events than those on warfarin (HR, 5.203; 95% CI, 1.056-25.633, p = 0.043). However, in patients without CKD, the aspirin group did not have a higher risk of thromboembolic events than the warfarin group (HR, 0.803; 95% CI, 0.225-2.867, p = 0.735). CONCLUSIONS: In Korean patients with AF and a CHADS2 score of 1, CKD may be an independent thromboembolic risk factor. In patients with CKD, warfarin may be superior to aspirin for lowering thromboembolic risk.

Cardiac Myxoma Originating from the Anterior Mitral Valve Leaflet

Primary cardiac tumors are rare and myxoma is the most common tumor among them. Cardiac myxoma usually occurs in the left atrium. Myxoma originating from mitral valve is extremely rare. We report a case of mitral valve myxoma. The tumor originated from the anterior mitral valve leaflet. The tumor was completely removed and replacement of the mitral valve was not done.

Importance of Clinical and Echocardiographic Hemodynamic Assessment in Chronic Pulmonary Embolism

We describe a 42-year-old man presenting to the emergency department with cardiogenic shock. He had a prior history of acute pulmonary embolism (PE), and had been on anticoagulation for 2 years. Although computed tomographic pulmonary angiography performed at the emergency department showed no change in the extent of PE and did not support a role of surgical treatment, pulmonary embolectomy was recommended by attending physician based on clinical and echocardiographic hemodynamic findings like unstable vital sign and markedly enlarged right ventricle with severely depressed systolic function. Surgery confirmed the presence of fresh thrombi. After surgery, hemodynamic status was progressively improved, but the patient died due to pneumonia and pulmonary hemorrhage.