Diagnostic significance of paradoxical left ventricular hypertrophy in detecting cardiac amyloidosis.

Background: Cardiac amyloidosis (CA) progresses rapidly with a poor prognosis. Therefore, methods for early diagnosis that are easily accessible in any hospital, are required. We hypothesized that based on the pathology of CA, morphological left ventricular hypertrophy (LVH) without electrical augmentation, namely paradoxical LVH, could be used to diagnose CA. This study aimed to investigate whether paradoxical LVH has diagnostic significance in identifying CA in patients with LVH. Methods: Patients who presented with left ventricular (LV) wall thickness ≥ 12 mm on cardiac magnetic resonance (CMR) were enrolled from a multicentre CMR registry. Paradoxical LVH was defined as a LV wall thickness ≥ 12 mm on CMR, SV1 + RV5 < 3.5 mV, and a lack of secondary ST-T abnormalities. The diagnostic significance of paradoxical LVH in identifying CA was assessed. Results: Of the 110 patients enrolled, 30 (27 %) were diagnosed with CA and 80 (73 %) with a non-CA aetiology. The CA group demonstrated paradoxical LVH more frequently than the non-CA group (80 % vs. 16 %, P < 0.001). It was an independent predictor for detecting CA in patients with LVH (odds ratio: 33.44, 95 % confidence interval: 8.325-134.3, P < 0.001). The sensitivity, specificity, positive predict value, negative predict value and accuracy of paradoxical LVH for CA detection were 80 %, 84 %, 65 %, 92 % and 83 %, respectively. Conclusions: Paradoxical LVH can be used for identifying CA in patients with LVH. Our findings could contribute to the early diagnosis of CA, even in non-specialized hospitals.

Impact of pulmonary vein anatomy and left atrial size on postoperative atrial fibrillation after esophagectomy for esophageal cancer.

BACKGROUND: This study aimed to investigate the relationship between postoperative atrial fibrillation (POAF) after esophagectomy and pre-existing cardiac substrate. METHODS: We retrospectively analyzed 212 consecutive patients from between July 2010 and December 2022 who were scheduled to undergo esophagectomy for esophageal cancer without previous history of atrial fibrillation. All the patients underwent both echocardiography and contrast-enhanced multi-detector computed tomography (MDCT). RESULTS: POAF occurred in 49 patients (23.1%). Multivariable logistic analysis demonstrated that independent predictors for POAF were age [OR; 1.06 (1.01-1.10), P < 0.01), three-field lymph node dissection [OR; 2.55 (1.25-5.23), P < 0.01), left atrial dilatation (> 35 mm) assessment by echocardiography [OR; 3.05 (1.49-6.25), P < 0.01) and common left pulmonary vein [OR; 3.03 (1.44-6.39), P < 0.01). The correlation coefficient was high for left atrial dimensions assessed by echocardiography and MDCT (r = 0.91, P < 0.01). Combination of left atrial dilatation by echocardiography and common left pulmonary vein had high odds ratio [OR; 8.10 (2.62-25.96), P < 0.01). Instead of echocardiographic assessment, combination of left atrial enlargement (> 35 mm) assessed by MDCT and common left pulmonary vein also showed high odds ratio for POAF [OR; 11.23 [2.19-57.63], P < 0.01). CONCLUSION: Incidence of POAF after esophagectomy was related to both left atrial enlargement and common left pulmonary vein assessed by preoperative MDCT. Additional analysis of atrial size and pulmonary vein variation would facilitate preoperative assessment of the risk of POAF, but future studies must ascertain therapeutic strategy.

Relationship between postoperative atrial fibrillation and its recurrence after lung resection.

PURPOSE: Atrial fibrillation (AF) frequently occurs after pulmonary resection and is commonly referred to as postoperative atrial fibrillation (POAF). This study explored whether or not POAF is related to the recurrence of AF in the chronic phase. METHODS: A total of 1311 consecutive patients without a history of AF who underwent lung resection based on a diagnosis of lung tumor were retrospectively analyzed. RESULTS: POAF occurred in 46 patients (3.5%), and a logistic regression analysis revealed that the age (p < 0.05), history of hyperthyroidism (p < 0.05), and major lung resection (p < 0.05) were independent predictors of POAF. AF events in the chronic phase were observed in 15 (32.6%) and 45 (3.6%) patients with and without POAF, respectively. A Cox regression analysis revealed that POAF was the only independent predictor of AF development in the chronic phase (p < 0.01). The Kaplan-Meier curve and log-rank test revealed that the cumulative incidence of AF in the chronic phase was significantly higher in patients with POAF than in those without POAF (p < 0.01). CONCLUSION: POAF was an independent predictor for AF in the chronic phase after lung resection. Further investigations including cases of catheter ablation and optimal medical therapy for patients with POAF after lung resection are needed.

Risk Factors for Chronic Atrial Fibrillation Development After Esophagectomy for Esophageal Cancer.

BACKGROUND: This study investigates the prognosis of patients with postoperative atrial fibrillation (POAF), aiming to elucidate predictors of occurrence of atrial fibrillation (AF) in the chronic phase after esophagectomy. METHODS: We retrospectively analyzed 415 consecutive patients between July 2010 and December 2021 who were scheduled to undergo esophagectomy for esophageal cancer and had no previous history of AF. RESULTS: POAF occurred in 73 patients (18%). Their ages were higher than those without POAF (72 [66-77] vs 68 [62-75], P < 0.01). Three-field lymph node dissection was more frequent in patients with POAF (63% vs 50%, P = 0.04). Overall survival rates were not significantly different between those with and without POAF in patients with stage III/IV cancer (P = 0.37), but overall survival rate of patients with POAF was lower than in those without POAF in stage I/II cancer (P = 0.03). Seventeen patients (4.1%) had recurrence of AF or new onset 31 days after esophagectomy. POAF was the only independent predictor of AF development in the chronic phase (HR: 4.09, 95%CI: [1.42-11.74], P = 0.01). AF development in the chronic phase was observed in 8 patients (11.0%) with and 9 patients (2.6%) without POAF (P < 0.01). AF development rates were not significantly different in patients with stage III/IV cancer (P = 0.05), but there was significant difference in patients with stage I/II cancer (P < 0.01). CONCLUSION: The occurrence of POAF after esophagectomy is related with future development of AF and overall survival prognosis. Future studies must ascertain optimal therapeutic strategy.

Real-time venography-guided extrathoracic puncture technique for cardiovascular implantable electronic device implantation.

Central venous access is an essential technique for cardiovascular implantable electronic device (CIED) implantation, and the use of axillary vein approach has recently been increasing. This study sought to examine whether real-time venography-guided extrathoracic puncture facilitates the procedure. We retrospectively analyzed 179 consecutive patients who underwent CIED implantation using the axillary vein puncture method. Patients were divided into two groups: the conventional method group (CG, n = 107) and the real-time venography-guided group (RG, n = 82). The application of real-time venography was at the discretion of individual operators. Operators with experience of less than 50 CIED implantations were defined as inexperienced operators in this study. Puncture duration and number of attempts were significantly less in the RG group than in the CG group (283 ± 198 vs. 421 ± 361 s, p < 0.01, and 3.19 ± 2.00 vs. 4.18 ± 2.85, p < 0.01). These benefits of real-time venography were observed in inexperienced operators, but not in experienced operators. In addition, the success rate without extra attempts at puncture was higher in the RG group (54% vs. 32%, p < 0.01). Although the total amount of contrast medium was higher in the RG group (16.3 ± 4.1 mL vs. 11.9 ± 6.6 mL, p < 0.01), serum levels of creatinine pre- and post-operation were not different in the two groups (p = NS). We concluded that real-time venography is a safe and effective method for axillary vein puncture, especially in inexperienced operators.

Cancer-related vulnerable lesions in patients with stable coronary artery disease.

BACKGROUND: Coronary artery disease (CAD) has become a major cause of morbidity and mortality in cancer survivors. It is still unclear whether cancer history influences lesion characteristics. The purpose of this study was to investigate cancer-related lesion morphology in patients with CAD. METHODS: This study enrolled 400 patients with stable CAD. The patients were classified into a cancer survivor group (n = 69) and a noncancer group (n = 331). We investigated coronary lesion morphology by optical coherence tomography, and we assessed the prognosis in terms of both all-cause mortality and major adverse cardiovascular events (MACE). RESULTS: Adenocarcinoma was the most common histopathological diagnosis. Serum C-reactive protein levels were significantly higher in the cancer survivor group than in the noncancer group (cancer survivors 0.12 [0.05-0.42] mg/dL vs. noncancer 0.08 [0.04-0.17] mg/dL, p = 0.019). The cancer survivor group was more likely than the noncancer group to have thrombi (cancer survivors 30.4% vs. noncancer 15.4%, p = 0.004), and layered fibrotic plaques (LFPs; cancer survivors 18.8% vs. noncancer 3.6%, p < 0.0001). Cancer survivors had poorer outcomes than noncancer controls in terms of both all-cause mortality (p = 0.020) and MACE (p = 0.036). CONCLUSIONS: Because of underlying inflammation, CAD patients with cancer had more high-risk lesions than those without cancer, which could result in poorer prognosis for the former. This result might inform the management of CAD in cancer patients in terms of secondary prevention.

Impact of left ventricular ejection fraction and preoperative hemoglobin level on perioperative adverse cardiovascular events in noncardiac surgery.

The prediction of a perioperative adverse cardiovascular event (PACE) is an important clinical issue in the medical management of patients undergoing noncardiac surgery. Although several predictors have been reported, simpler and more practical predictors of PACE have been needed. The aim of this study was to investigate the predictors of PACE in noncardiac surgery. We retrospectively analyzed 723 patients who were scheduled for elective noncardiac surgery and underwent preoperative examinations including 12-lead electrocardiography, transthoracic echocardiography, and blood test. PACE was defined as cardiac death, non-fatal myocardial infarction, unstable angina, congestive heart failure, arrhythmia attack that needs emergency treatment (rapid atrial fibrillation, ventricular tachycardia, and bradycardia), acute pulmonary embolism, asystole, pulseless electrical activity, or stroke during 30 days after surgery. PACE occurred in 54 (7.5%) of 723 patients. High-risk operation (11% vs. 3%, p = 0.003) was more often seen, left ventricular ejection fraction (LVEF) (55 ± 8% vs. 60 ± 7%, p = 0.001) and preoperative hemoglobin level (11.8 ± 2.2 g/dl vs. 12.7 ± 2.0 g/dl, p = 0.001) were lower in patients with PACE compared to those without PACE. By multivariate logistic regression analysis, high-risk operation (odds ratio (OR): 7.05, 95% confidence interval (CI) 2.16-23.00, p = 0.001), LVEF (OR 1.06, every 1% decrement, 95% CI 1.03-1.09, p = 0.001), and preoperative hemoglobin level (OR 1.22, every 1 g/dl decrement, 95% CI 1.07-1.39, p = 0.003) were identified as independent predictors of PACE. Receiver operating characteristic analysis demonstrated that LVEF of 58% (sensitivity = 80%, specificity = 61%, area under the curve (AUC) = 0.723) and preoperative hemoglobin level of 12.2 g/dl (sensitivity = 63%, specificity = 64%, AUC = 0.644) were optimal cut-off values for predicting PACE. High-risk operation, reduced LVEF, and reduced preoperative hemoglobin level were independently associated with PACE in patients undergoing noncardiac surgery.

Effects of intravenous bolus injection of nicorandil on renal artery flow velocity assessed by color Doppler ultrasound.

BACKGROUND: Previous animal studies have shown that a potassium channel opener, nicorandil, provokes vasodilation in renal microvasculature and increases renal blood flow. We conducted a clinical study that aimed to evaluate the effect of nicorandil on renal artery blood flow in comparison with nitroglycerin by using color Doppler ultrasound. METHODS: The present study enrolled 40 patients with stable coronary artery disease who had no renal arterial stenosis and renal parenchymal disease. The patients received intravenous administration of nicorandil (n=20) or nitroglycerin (n=20). Before and after the administration, renal artery blood flow velocity was measured by color-guided pulsed-wave Doppler. RESULTS: The peak-systolic, end-diastolic, and mean renal artery blood flow velocities before the administration were not different between the nicorandil group and the nitroglycerin group. The peak-systolic (79±15cm/s to 99±21cm/s, p<0.001; and 78±19cm/s to 85±19cm/s, p=0.004), end-diastolic (22±5cm/s to 28±8cm/s, p<0.001; and 24±6cm/s to 26±6cm/s, p=0.005) and mean (41±6cm/s to 49±9cm/s, p<0.001; and 43±9cm/s to 45±9cm/s, p=0.009) renal artery flow velocities increased significantly in either group. The nominal changes in the peak-systolic (20±10cm/s vs. 7±8cm/s, p<0.001), end-diastolic (5±4cm/s vs. 2±3cm/s, p=0.001), and mean (8±5cm/s vs. 2±2cm/s, p<0.001) renal artery blood flow velocities were significantly greater in the nicorandil group compared with the nitroglycerin group. CONCLUSION: Intravenous nicorandil increased renal artery blood flow velocity in comparison with nitroglycerin. Nicorandil has a significant effect on renal hemodynamics.

Impact of functional focal versus diffuse coronary artery disease on bypass graft patency.

BACKGROUND: Pressure guidewire pullback recording can differentiate between functional focal and diffuse disease types in coronary artery disease. The aim of this study was to compare the outcome of coronary artery bypass graft (CABG) patency between patients with functional focal versus diffuse disease types in recipient coronary arteries. METHODS AND RESULTS: We investigated 89 patients who underwent pressure guidewire pullback in the left anterior descending (LAD) artery before CABG using internal mammary artery (IMA). Based on the pressure guidewire pullback data, the LAD lesions were classified into functional focal disease (abrupt pressure step-up; n=58) or functional diffuse disease (gradual pressure increase; n=31). Follow-up computed tomography (CT) angiography was conducted within 1year after CABG to assess the bypass graft patency. Pre CABG, LAD angiographic percent diameter stenosis (57±10% vs. 54±12%, p=0.228) and fractional flow reserve (FFR) (0.68±0.07 vs. 0.69±0.07, p=0.244) were not different between the functional focal and diffuse disease groups. The CABG procedure characteristics were similarly comparable between the two groups. In the follow-up CT angiography after CABG, occlusion or string sign of the IMA graft to LAD was more frequently observed in the functional diffuse disease group than in the functional focal disease group (26% vs. 7%, p=0.021). CONCLUSION: In CABG, functional diffuse disease in the recipient coronary artery was associated with an increased risk of the graft failure in comparison with functional focal disease.

Early Recurrence After Pulmonary Vein Isolation of Paroxysmal Atrial Fibrillation With Different Ablation Technologies - Prospective Comparison of Radiofrequency vs. Second-Generation Cryoballoon Ablation.

BACKGROUND: Inflammation plays a prominent role in the etiology of the early recurrence of atrial fibrillation (ERAF). We prospectively compared the proportion of ERAF and time-course patterns of biomarkers between radiofrequency (RF) and cryoballoon (CB) ablation. METHODS AND RESULTS: We enrolled 82 consecutive paroxysmal AF patients undergoing pulmonary vein (PV) isolation, performed with either a 28-mm 2nd-generation CB and 3-min freeze technique or point-by-point RF ablation. Each group had 41 patients. In the RF group, all PVs were successfully isolated with 28.9 ± 6.5 min of RF delivery. In the CB group, a mean of 5.3 ± 1.4 applications/patient was delivered. The proportion of ERAF was similar between the groups. The time-course patterns significantly differed between the groups for high-sensitivity C-reactive protein (hs-CRP) value (P=0.006) and myocardial injury markers (P<0.0001). Greater myocardial injury was observed in the CB than in the RF group (P<0.0001), whereas the peak hs-CRP value was comparable between the groups. The 2-day post-procedure hs-CRP value was the sole factor correlating with ERAF as identified by the multivariable analysis (hazard ratio 1.697; 95% confidence interval, 1.005-2.865; P=0.048) in the RF, but not the CB group. CONCLUSIONS: The proportion of ERAF was comparable after RF and 2nd-generation CB ablation. Despite CB ablation exhibiting greater myocardial injury than RF ablation, the inflammatory responses were comparable between the groups. The inflammatory response extent predicted ERAF post-RF ablation but not post-CB ablation.

Impact of the order of the targeted pulmonary vein on the vagal response during second-generation cryoballoon ablation.

BACKGROUND: Radiofrequency applications around pulmonary vein (PV) ostia often induce vagal reflexes. OBJECTIVE: This study aimed to evaluate the impact of the order of the targeted PV on the vagal response during second-generation cryoballoon ablation. METHODS: Eighty-one consecutive paroxysmal atrial fibrillation (AF) patients undergoing cryoballoon ablation were prospectively enrolled. PV isolation was performed with one 28-mm second-generation balloon using a 3-minute freeze technique. In the first 39 patients, the left superior PV (LSPV) was initially targeted. In the second 42, the LSPV was targeted following the right PVs. RESULTS: Baseline rhythms were sinus rhythm and AF in 34 and 5 patients in the first group, and 34 and 8 in the second group, respectively. In the first group, sinus bradycardia/arrest requiring back-up pacing occurred in 13 patients (38.2%) at a median of 41.0 (10.0-55.5) seconds after balloon deflation (90 [60-100] seconds post freezing), and pauses requiring pacing in 1 (20.0%) with AF. In the second group, no sinus bradycardia/arrest occurred throughout the procedure; however, atrioventricular block requiring back-up pacing occurred 21 seconds after balloon deflation in 1 patient in whom right superior PV (RSPV) ablation was performed for only 60 seconds owing to right phrenic nerve injury. The cycle length was similar at baseline and post PV isolation between the 2 groups, and significantly shorter during RSPV ablation (P < .0001) in both. In total, marked vagal responses were significantly higher in the first than second group (14/39 vs 1/42, P < .0001). CONCLUSIONS: LSPV cryoballoon ablation often provoked marked vagal responses; however, preceding RSPV ablation markedly suppressed this response.

Adenosine Triphosphate Test After Cryothermal Pulmonary Vein Isolation: Creating Contiguous Lesions Is Essential for Eliminating Dormant Conduction.

BACKGROUND: Adenosine triphosphate (ATP) testing reveals dormant pulmonary vein (PV) conduction after electrical PV isolation (PVI). This study aimed to evaluate the incidence of latent PV conduction after cryothermal PVI. METHODS: Fifty-four consecutive paroxysmal atrial fibrillation patients undergoing cryothermal PVI were prospectively enrolled. PVI was performed with one 28-mm second-generation balloon using a 3-minute freeze technique, and touch-up lesions were created by focal cryothermal applications. ATP testing was performed following PVI with a 20-mm circular mapping catheter placed in each PV. RESULTS: Of 217 PVs, 205 (94.5%) were isolated using a cryoballoon, and 12 required additional focal ablation. ATP testing was performed in 46 patients for 173 and 8 PVs, which were isolated by cryoballoons and focal ablation, respectively. No dormant PV conduction was provoked in any PVs, which were isolated by cryoballoons, whereas 4 (50.0%) out of 8 PVs requiring focal ablation had transient ATP-provoked reconnections (0 vs. 50.0%, P < 0.0001) with a median duration of 11.3 (10.7-17.1) seconds. The latent PV conduction site was identical to the residual conduction gap site after cryoballoon ablation in all. All latent conduction was successfully eliminated by 2 (2.0-9.5) additional focal applications. At a mean follow-up of 7.7 ± 1.6 months, 81.5% of the patients were arrhythmia free after a single procedure. CONCLUSIONS: No dormant PV conduction was provoked in PVs, which were isolated by 28-mm second-generation cryoballoons, but was provoked in 50% of PVs, which were isolated by focal cryoablation. These findings suggest that creating contiguous lesions is essential for eliminating dormant conduction in cryothermal ablation.

Prospective Evaluation of Bilateral Diaphragmatic Electromyograms During Cryoballoon Ablation of Atrial Fibrillation.

BACKGROUND: Left phrenic nerve injury (PNI) can occur during cryoballoon ablation of the left pulmonary veins (PVs). This study aimed to evaluate the feasibility of monitoring the bilateral phrenic nerve function during cryoballoon ablation of atrial fibrillation (AF). METHODS: Fifty consecutive paroxysmal AF patients undergoing cryoballoon ablation using one 28-mm second-generation balloon were prospectively enrolled. Bilateral diaphragmatic compound motor action potentials (CMAPs) were obtained from modified surface electrodes by pacing from the bilateral subclavian veins, and monitored during 3-minute cryoballoon applications at the ipsilateral PVs. RESULTS: One hundred ninety of 202 PVs were successfully isolated exclusively using 28-mm cryoballoons. CMAPs could be obtained in all except 3 cases with catheter inaccessibility in the left subclavian vein. The left and right CMAP amplitudes were similar at baseline (1.04 ± 0.41 mV vs. 1.01 ± 0.43 mV, P = 0.49). Among 105 left and 132 right PV applications while monitoring CMAPs, 2 (1.9%) and 13 (9.8%) applications were interrupted for a decreased CMAP amplitude (P = 0.01). Among them, CMAPs decreased due to right PNI in 4 applications/patients and to catheter dislodgement in the remaining applications. PNI remained in 1 and recovered in the remaining 3 patients one day after the procedure. Applications without requiring interruptions exhibited no significant CMAP amplitude changes throughout the applications, and the time-course pattern was similar between the bilateral CMAPs (P = 0.292). CONCLUSIONS: A stable bilateral diaphragmatic CMAP could be similarly obtained during cryoballoon applications in the vast majority of patients. Monitoring CMAPs might be useful to anticipate not only right but also left PNI during cryoballoon ablation.

Recurrence after "long-term success" in catheter ablation of paroxysmal atrial fibrillation.

BACKGROUND: The latest guidelines define "long-term success" as freedom from atrial arrhythmia recurrence more than 36 months after procedures without any antiarrhythmic drug therapy. OBJECTIVE: The purpose of this study was to investigate the clinical outcomes and procedural findings in patients with recurrence beyond "long-term success." METHODS: Among patients who underwent pulmonary vein (PV) antrum isolation for drug-refractory symptomatic paroxysmal atrial fibrillation (AF), 37 in whom recurrent arrhythmias were observed during annual follow-up after "long-term success" and who underwent repeat procedures for recurrent arrhythmias were included in the study. RESULTS: The time from the latest procedure to recurrence was a median of 61 ([25th, 75th percentiles]: [51-77.5]) months. Recurrent arrhythmia type was paroxysmal in 22 patients (59.5%) and persistent in 15 (40.5%). Recurrent arrhythmias were atrial tachycardia (AT) in 13 patients (35.1%), including 8 with AT unrelated to PVs. Repeat procedures were performed a median of 2.0 [1.0-4.0] months after identifying recurrent episodes. Recovered PV conduction was found in 29 patients (78.4%) and non-PV foci in 4 (10.8%). Freedom from recurrence 1 year after repeat procedures was 63.3%. Seven patients (18.9%) underwent further repeat procedures a median of 7.0 [2.0-28.0] months after repeat procedures and had no PV reconnections. In total, AF/AT unrelated to PVs was present in 24 patients (64.9%). In contrast, arrhythmias related to PVs were observed in 2 patients (5.4%) during a total of 46 repeat procedures after "long-term success." CONCLUSION: Although PV reconnections were commonly found even after "long-term success," AF/AT unrelated to PVs was assumed to be present in the majority of this population.

Adenosine-Provoked Atrial Fibrillation Originating From Non-Pulmonary Vein Foci: The Clinical Significance and Outcome After Catheter Ablation.

OBJECTIVES: The goal of this study was to systematically investigate the incidence and clinical significance of non-pulmonary vein (PV) foci revealed by adenosine/adenosine triphosphate (ATP) testing during atrial fibrillation (AF) ablation. BACKGROUND: ATP is reported to provoke AF. METHODS: A total of 464 patients with consecutive paroxysmal AF undergoing ATP testing after PV antrum isolation were included. RESULTS: AF originating from non-PV foci was provoked in 26 (5.6%) total patients during first (n = 20) or repeat (n = 8) ablation procedures. Dormant PV conduction was also revealed by ATP testing in 6 patients. Non-PV foci were located in the superior vena cava (SVC) (i.e., the SVC group) and atria (i.e., the atria group) in 10 and 18 (9 each in the right and left atria) patients, respectively. In the multivariable analysis, being female was the sole independent predictor of ATP-provoked AF originating from non-PV foci (hazard ratio [HR]: 2.52 [95% confidence interval (CI): 1.069 to 5.929]; p = 0.034). After additional ablation targeting non-PV foci, freedom from recurrent AF after the last procedure was similar between the SVC group and patients without ATP-provoked AF but was significantly lower in the atria group than in others (p = 0.0008). Atria group membership (HR: 3.725 [95% CI: 1.692 to 8.199]; p = 0.001) and being female (HR: 1.538 [95% CI: 1.189 to 1.989]; p = 0.001) were significant independent predictors associated with recurrence after the last procedure in the multivariable Cox regression model. CONCLUSIONS: ATP provoked AF originating from non-PV foci under isoproterenol in 5.6% of patients undergoing paroxysmal AF ablation. ATP testing might be useful for identifying and eliminating AF originating from the SVC. The atria group was associated with a poor outcome after the last procedure despite efforts to eliminate non-PV foci.

Prevalence and clinical outcome of phrenic nerve injury during superior vena cava isolation and circumferential pulmonary vein antrum isolation using radiofrequency energy.

BACKGROUND: Phrenic nerve injury (PNI) is recognized as an important complication during atrial fibrillation ablation. This study aimed to investigate the incidence and outcome of PNI during superior vena cava isolation (SVCI) and circumferential pulmonary vein isolation (CPVI) using radiofrequency (RF) energy and the factors associated with its occurrence. METHODS AND RESULTS: Five hundred sixty-seven consecutive patients who underwent SVCI after CPVI without substrate modification who completed a 12-month follow-up were retrospectively analyzed. Point-by-point RF applications were applied with maximum energy settings of 35 W and 30 seconds for the SVCI. In the former 210 patients, sites where pacing captured the PN were avoided whenever possible; however, the maximum power was 35 W. In the latter 357 patients, RF energy was delivered regardless of PN capture; however, the power at PN capture sites was limited to 10 W during continuous diaphragmatic movement monitoring on fluoroscopy. Circumferential pulmonary vein isolation and SVCI were successfully achieved in all. Twelve patients (2.1%) had PNI during SVCI but not during CPVI. Phrenic nerve injury completely recovered in all patients a median of 8.0 months after the procedure. The prevalence was higher in the former period (3.8% vs 1.1%; P = .03). A multivariate logistic regression analysis revealed that the study period (odds ratio 3.546; 95% CI 1.051-11.965; P = .041) was the sole independent predictor for identifying patients with PNI during SVCI. CONCLUSIONS: Phrenic nerve injury occurred in 2.1% of the patients. All occurred during SVCI but not during contemporary CPVI. Energy titration and continuous diaphragmatic movement monitoring significantly decreased the incidence during SVCI.

Is visceral fat really a coronary risk factor? A multi-detector computed tomography study.

Metabolic syndrome (MS) is currently considered to be a risk factor for arteriosclerotic disease. The accumulation of visceral fat leads to arteriosclerotic disease after other risk factors have developed and either direct or mutual effects occur. The aim of this study was to verify whether visceral fat serves as an independent coronary risk factor. A total of 3157 patients who had undergone multi-detector computed tomography (MDCT) were analyzed via computed tomographic angiography and the measurement of their visceral fat area. Coronary arteries with > 70% stenosis were considered to be significant. The visceral fat area was measured at the umbilical level, and an area of 100 cm2 or more was defined as visceral obesity. Coronary risk factors (ie, hypertension, dyslipidemia, diabetes mellitus, family history, and smoking) were obtained from the patient medical records. The patients were divided into two groups: a visceral obesity group, 1130 patients (137.0 ± 31.1 cm2) and a nonvisceral obesity group, 2027 patients (57.3 ± 25.8 cm2). A significant difference in the incidence of coronary stenosis between the two groups was observed. According to multivariable analysis, the factors affecting coronary stenosis were age, gender, dyslipidemia, diabetes mellitus, and the ratio of visceral to subcutaneous fat. Visceral obesity was not found to be an independent coronary risk factor. Visceral obesity demonstrated the predominant presence of coronary risk factors.

Association between circulating monocyte subsets and in-stent restenosis after coronary stent implantation in patients with ST-elevation myocardial infarction.

BACKGROUND: Recent studies have shown that monocytes in human peripheral blood are heterogeneous. The clinical significance of 2 distinct monocyte subsets as a marker of late in-stent restenosis (ISR) following implantation of bare-metal stents (BMSs) in patients with acute myocardial infarction (AMI) was examined. METHODS AND RESULTS: Seventy-one consecutive patients with AMI who underwent BMS implantation were enrolled in the study. Peripheral blood was collected 12 days after AMI onset. Two distinct monocyte subsets (CD14(+)CD16(-)CCR2(+) and CD14(+)CD16(+)CX3CR1(+)) were measured by flow cytometry. All patients underwent angiography at a scheduled follow up after 9 months. CD14(+)CD16(+)CX3CR1(+) monocyte subset counts were significantly higher in patients with restenosis than in patients without restenosis, whereas neither the total monocytes nor the CD14(+)CD16(-)CCR2(+) subset counts differed significantly between the 2 groups of patients. There was also a significant positive correlation between the CD14(+)CD16(+)CX3CR1(+) monocyte counts and angiographic late lumen loss. In multivariate analysis, the CD14(+)CD16(+)CX3CR1(+) monocyte count was an independent predictor for in-stent late lumen loss. CONCLUSIONS: CD14(+)CD16(+)CX3CR1(+) monocytes might have a role in ISR following coronary BMS implantation in patients with AMI.

Clinical characteristics of patients with kawasaki disease and levels of peripheral endothelial progenitor cells and blood monocyte subpopulations.

BACKGROUND: Coronary sequelae that persist after Kawasaki disease (KD) have been associated with coronary vascular events in adolescents and young adults. The aim of this study was to investigate the relationship between coronary sequelae late after KD and circulating endothelial progenitor cells (EPCs), as a marker of vascular repair, or monocyte subsets as a marker of inflammation. METHODS AND RESULTS: The 31 KD patients were divided into 3 groups according to the type of coronary artery lesion (CAL): group 1 consisted of 14 patients with persistent aneurysm; group 2 consisted of 9 patients with regressed aneurysms; group 3 included 8 KD patients with normal coronary arteries from disease onset. The control group (group 4) consisted of 10 healthy subjects. Flow cytometric analysis was used to quantify circulating EPCs defined as CD34(+)KDR(+) cells and 2 distinct monocyte subsets (CD14(+)CD16(+) and CD14(+)CD16(-)). The number of EPCs in group 1 and group 2 was significantly decreased compared with group 4. In contrast, neither the number of CD14(+)CD16(+) monocytes nor that of CD14(+)CD16(-) monocytes was significantly different among the 4 groups. Finally, there were not any significant relationship between the numbers of EPCs and the 2 monocyte subsets. CONCLUSIONS: There are lower numbers of EPCs in the chronic phase of KD, irrespective of both CAL formation and monocyte subsets.

Relation of microchannel structure identified by optical coherence tomography to plaque vulnerability in patients with coronary artery disease.

Increased neovascularization in atherosclerotic plaques is associated with plaque vulnerability. The high resolution of optical coherence tomography (OCT) might provide a chance to directly visualize plaque neovascularization in vivo. The aim of the present study was to investigate the relation between microchannels in culprit plaques identified by OCT and plaque vulnerability in patients with coronary artery disease. A total of 63 consecutive patients with coronary artery disease who had undergone both OCT and intravascular ultrasound before any interventions to examine culprit lesion morphologies were enrolled. Microchannel was defined as a no-signal tubuloluminal structure on the cross-sectional optical coherence tomographic image. Microchannels were found in 24 (38%) of the 63 patients. The patients were divided into 2 groups according to the presence or absence of microchannels. The frequency of plaque rupture tended to be greater in the microchannel group (50% vs 28%, p = 0.11). The thickness of the fibrous cap (median 60 vs 100 microm, p = 0.001) was significantly less in the patients with microchannels, and significant differences were found in the frequency of thin-cap fibroatheroma (54% vs 21%, p = 0.012) and positive remodeling (67% vs 36%, p = 0.02) between the 2 groups. The high-sensitivity C-reactive protein levels in the microchannel group was significantly greater than those in the no-microchannel group (median 0.27 vs 0.13 mg/dl, p = 0.015). Moreover, increased microchannel counts were associated with greater high-sensitivity C-reactive protein levels (p = 0.01). In conclusion, a significant relation was found between the presence of microchannels in plaques identified by OCT and plaque vulnerability in patients with coronary artery disease.