Feasibility of catheter ablation in patients with persistent atrial fibrillation guided by fragmented late-gadolinium enhancement areas.

BACKGROUND: A computer simulation model has demonstrated that atrial fibrillation (AF) driver can be attached to heterogeneous fibrosis assessed by late gadolinium enhancement magnetic resonance imaging (LGE-MRI). However, it has not been well elucidated in patients with persistent AF. The aim of this study was to investigate whether radiofrequency (RF) applications in the fragmented LGE area (FLA) could terminate AF or convert it to atrial tachycardia (AT) and improve the rhythm outcome. METHODS: A total of 31 consecutive persistent AF patients with FLAs were enrolled (FLA ablation group, mean age: 69 ± 8 years, mean left atrial diameter: 42 ± 6 mm). A favorable response was defined as direct AF termination or AT conversion during RF applications at the FLA. The rhythm outcome was compared between the FLA ablation group and FLA burden-matched pulmonary vein isolation (PVI) group. RESULTS: Favorable responses were found in 15 (48%) of 31 patients in the FLA group (AF termination in seven, AT conversion in eight patients), but not in the PVI group. AF recurrence at 12 months follow-up was significantly less in the FLA ablation group than in the PVI group (4 [13%] vs. 12 [39%] of 31 patients, log-rank p = .023). In patients with a favorable response, AT recurred in 1 (7%) of 15 patients, but AF did not. CONCLUSIONS: FLA ablation could terminate AF or convert it to AT in half of the patients. No AF recurrence was documented in patients with a favorable response.

Lesion distribution after cryoballoon ablation and hotballoon ablation: Late-gadolinium enhancement magnetic resonance imaging analysis.

INTRODUCTION: Pulmonary vein isolation (PVI) lesions after cryoballoon ablation (CBA) are wide and continuous, however, the distribution can depend on the pulmonary vein (PV) size. We sought to assess the relationship between the lesion distribution and PV size after CBA and hotballoon ablation (HBA). METHODS AND RESULTS: A total of 80 consecutive patients who underwent PVI were enrolled (40 with CBA). The lesions were visualized by late-gadolinium enhancement magnetic resonance imaging. The lesion width, lesion gaps, and distance from the PV ostium (PVos) to distal lesion edge (DLE) were assessed. If the DLE extended inside the PV, the value was expressed as a negative value. Although the lesion width was significantly wider in the CB group (7.8 ± 2.0 vs 4.9 ± 1.0 mm, P < .001), the number of lesion gaps was significantly less in the HB group (2.9 ± 2.4 vs 1.3 ± 1.4 gaps, P = .001). The distance from the PVos to DLE was a negative value in both groups, but the impact was significantly greater (-1.5 ± 1.8 vs -0.2 ± 1.2 mm, P < .001) and negatively correlated with PV size in the CB group, but not in HB group (r = -0.27, P = .007). The AF recurrence 12 months after the procedure did not differ (5 [12.5%] of 40 in the CB group vs 4 [10%] of 40 in the HB group, P = .695). CONCLUSIONS: The PVI lesions after HBA were characterized by (a) narrower, but (b) more continuous, (c) smaller lesion inside the PV, and (d) irrespective of PV size as compared to that after CBA.

A Comparison of Quantitative T2 Mapping on Cardiovascular Magnetic Resonance Imaging with Metaiodobenzylguanidine Scintigraphy and Left Ventricular Functional Recovery in Dilated Cardiomyopathy: A Retrospective Pilot Study.

OBJECTIVE: Metaiodobenzylguanidine (MIBG) scintigraphy is used to assess heart failure (HF) severity and to predict cardiac functional recovery. Cardiovascular magnetic resonance (CMR) imaging has recently been used to diagnosis HF. We evaluated CMR T2 mapping and MIBG scintigraphy in dilated cardiomyopathy (DCM) patients. METHODS: Consecutively, 22 DCM patients [aged 56.8 ± 13.4 years; 6 women and 16 men; left ventricular ejection fraction (LVEF), 31.9 ± 10.7%] who underwent T2 mapping and MIBG scintigraphy were retrospectively evaluated. Echocardiography results were recorded at baseline and the 6-month follow-up. Patients with an increased LVEF ≥15% between the 2 measures were considered to be responders. We measured each patient's T2 values and MIBG indices [the heart-to-mediastinum ratio (H/M) in the early phase, H/M in the delayed phase, and the washout rate (WOR)] at baseline. We compared these values between the 12 responders and 10 non-responders. RESULTS: The mean T2 value for all patients was 64.5 ± 6.6 ms. The mean values of early H/M, delayed H/M, and WOR were 2.06 ± 0.25, 1.94 ± 0.35, and 43.5 ± 11.8%, respectively. The T2 values were found to correlate with MIBG indices (p<0.05 for all) and were lower in the responders than non-responders (61.4 vs. 68.1 ms, p=0.013). MIBG indices were not significantly different. CONCLUSION: Our study shows that the T2 values correlated with the MIBG indices and were increased in non-responders. T2 mapping may be useful in assessing the cardiac function and functional recovery in DCM patients.

Optimal angulations for obtaining an en face view of each coronary aortic sinus and the interventricular septum: Correlative anatomy around the left ventricular outflow tract.

An optimal image intensifier angulation used for obtaining an en face view of a target structure is important in electrophysiologic procedures performed around each coronary aortic sinus (CAS). However, few studies have revealed the fluoroscopic anatomy of the target area. This study investigated the optimal angulation for each CAS and the interventricular septum (IVS). The study included 102 consecutive patients who underwent computed tomography coronary angiography. The optimal angle for each CAS was determined by rotating the volume-rendered image around the vertical axis. The angle formed between the anteroposterior axis and IVS was measured using the horizontal section. The frontal direction was defined as zero, positive, or negative if the en face view of the target CAS was obtained in the frontal view, left anterior oblique (LAO) direction, or right anterior oblique (RAO) direction, respectively. The optimal angles for the left, right, and non-CASs were 120.3 ± 10.5°, 4.8 ± 16.3°, and -110.0 ± 13.8°, respectively. The IVS angle was 42.6 ± 8.5°. Accordingly, the optimal image intensifier angulations for the left, right, and non-CASs and the IVS were estimated to be RAO 60°, LAO 5°, LAO 70°, and RAO 50°, respectively. The IVS angle was the most common independent predictor of the optimal angle for each CAS. Differences in the optimal angulations for each CAS and the IVS are demonstrated. The biplane angulation needs to be tailored according to the individual patients and target structures for electrophysiologic procedures.

Association between the rotation and three-dimensional tortuosity of the proximal ascending aorta.

Age-related morphological changes of the aorta, including dilatation and elongation, have been reported. However, rotation has not been fully investigated. We focused on the rotation of the ascending aorta and investigated its relationship with tortuosity. One hundred and two consecutive patients who underwent computed tomography coronary angiography were studied. The angle at which the en face view of the volume-rendered image of the right coronary aortic sinus (RCS) was obtained without foreshortening was defined as the rotation index. It was defined as zero if the RCS was squarely visible in the frontal view, positive if it rotated clockwise toward the left anterior oblique (LAO) direction, and negative if it rotated counter-clockwise toward the right anterior oblique (RAO) direction. The tortuosity was evaluated by measuring the biplane tilt angles formed between the ascending aorta and the horizontal line. The mean rotation index, posterior tilt angle viewed from the RAO direction (αRAO ), and anterior tilt angle viewed from the LAO direction (αLAO ) were 4.8 ± 16.3, 60.7 ± 7.0°, and 63.6 ± 9.0°, respectively. Although no correlation was observed between the rotation index and the αLAO (ß = -0.0761, P = 0.1651), there was a significant negative correlation between the rotation index and αRAO (ß = -0.1810, P < 0.0001). In multivariate regression analysis, the rotation index was an independent predictor of the αRAO (ß = -0.1274, P = 0.0008). Clockwise rotation of the proximal ascending aorta exacerbates the tortuosity by tilting the aorta toward the posterior direction.

Cardiovascular magnetic resonance tagging imaging correlates with myocardial dysfunction and T2 mapping in idiopathic dilated cardiomyopathy.

To evaluate the details of myocardial dysfunction in dilated cardiomyopathy (DCM) patients using tagging images and the correlation of tagging imaging with tissue characteristics. Circumferential strain (Ecc) derived from tagging images was measured in 15 normal (NML) subjects (15 males; mean age 28.5 years) and 12 DCM patients (7 males; mean age 48.9 years). The following parameters were compared: (1) the magnitude of peak Ecc (Ecc*); (2) the coefficient of variation of the time of Ecc* (CVtime*), which indexes dyssynchrony; and (3) descriptive findings of time-Ecc curves. We also evaluated the correlations of Ecc* in DCM patients with ejection fraction (EF), myocardial T2 values, and late gadolinium enhancement (LGE). Mean Ecc*s in DCM patients and NML subjects were -12.7 and -23.5%, respectively (P < 0.0001). Mean CVtime*s were 15.2 and 4.5%, respectively (P = 0.0002). The findings of pre-systolic extension and systolic stretch in the septum were observed in 6 (50%) and 10 (83.3%) DCM patients and in none of the NML participants. Ecc* was correlated with EF (P < 0.0001, R2 = 0.90) and T2 values (P = 0.018, R2 = 0.44) but not with LGE (P = 0.072, R2 = 0.28). Tagging images revealed the reduction of myocardial function as well as dyssynchrony in DCM patients. Myocardial dysfunction occurred coincidently with myocardial inflammation.

Predicting the response to cardiac resynchronization therapy using 99mTc-tetrofosmin myocardial scintigraphy in patients with drug-refractory heart failure: additional value of the washout of 99mTc-tetrofosmin.

OBJECTIVE: A lack of response to cardiac resynchronization therapy (CRT) has been reported in 20-40% of heart failure patients with left ventricular (LV) dyssynchrony who underwent treatment based on the established guidelines. The study aimed to investigate the relationship between (99m)Tc-tetrofosmin ((99m)Tc-TF) myocardial scintigraphy and the response to CRT. PATIENTS AND METHODS: Twenty-one patients with drug-refractory heart failure who underwent CRT were evaluated. All patients underwent (99m)Tc-TF myocardial scintigraphy before and after CRT. Single-photon emission computed tomography images of (99m)Tc-TF were acquired at 30 min and 3 h after injection and were used to determine the total defect score (TDS) and washout score (WOS). The change in the LV volume and ejection fraction (ΔLVEF) and relative reduction in left ventricular end-systolic volume (%ΔLVESV) were calculated as an index of LV functional recovery after CRT. Response to CRT was considered to have occurred when ΔLVEF was greater than 15% or when ΔLVEF was greater than 5% and %ΔLVESV was greater than 15%. RESULTS: Significant differences were observed between the patients who responded to CRT (the responder group, 13 patients) and the nonresponder group (eight patients) for both early and delayed TDS and WOS (P<0.05). Moreover, there was a good correlation between early TDS before CRT and both ΔLVEF and %ΔLVESV (P<0.01) and an excellent correlation between WOS before CRT and both ΔLVEF and %ΔLVESV (P<0.01). CONCLUSION: Evaluating the washout of (99m)Tc-TF in addition to myocardial perfusion before CRT using (99m)Tc-TF myocardial scintigraphy might be useful in drug-refractory heart failure patients.

Relationship of decreased accumulation of (99m)Tc-tetrofosmin on myocardial single-photon emission computed tomography images between QRS duration in dilated cardiomyopathy patient with left bundle branch block.

PURPOSE: This study aimed to clarify the relationship between severity of conduction delay in the left ventricle and myocardial uptake of (99m)Tc-tetrofosmin (TF) in dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB). METHODS AND RESULTS: Thirty-two DCM patients with LBBB underwent electrocardiography and (99m)Tc-TF myocardial single-photon emission computed tomography (SPECT). SPECT images were acquired at 30 min (early images) and 3 h (late images) after injection. We calculated the total defect score (TDS) using a 20-segment model with a 5-point scoring system. The TDS in early and late images was defined as the summed early score (SES) and summed late score (SLS), respectively. On early images, 29 of 32 patients (91%) had decreased tracer uptake in the septum. All patients showed a decreased tracer uptake in the septum on late images. A significant correlation was observed between TDS (both SES and SLS) and QRS duration, with SLS showing an excellent correlation (SES: r = 0.554, P < 0.001; SLS: r = 0.779, P < 0.0001). CONCLUSIONS: These findings suggest that in DCM patients with LBBB, hypoperfusion and myocardial damage in the septum might occur in accordance with an increase in the QRS duration.

Cardiovascular magnetic resonance T2 mapping can detect myocardial edema in idiopathic dilated cardiomyopathy.

Myocardial edema and inflammation play an important role in dilated cardiomyopathy (DCM). This pathologic condition can be identified noninvasively using cardiovascular magnetic resonance imaging (CMR). The purpose of this study was to determine the effectiveness of T2 values obtained with T2 mapping in the detection of edema in DCM patients, compared with that of conventional T2-weighted imaging (T2WI). CMR was used for 15 normal controls (NML) and 26 DCM patients. The DCM patients were classified as having either mild dysfunction with a left ventricular ejection fraction (EF) >35% or severe dysfunction with an EF ≤35%. Myocardial edema was assessed by both T2 mapping and T2WI. The differences between the T2 values determined from T2 mapping and the T2 ratios that were calculated from the T2WI were compared among the NML, mild DCM, and severe DCM patients. The T2 values for the NML, mild DCM, and severe DCM patients were 51.2 ± 1.6, 61.2 ± 0.37, and 67.4 ± 6.8, respectively (P < 0.05 for each pair), and the corresponding T2 ratios were 1.88 ± 0.09, 2.12 ± 0.37, and 2.04 ± 0.34, respectively (P > 0.05). T2 mapping clearly showed that the myocardial water content was larger in DCM patients than in NML controls and that the myocardial water content increased as the disease progressed. Thus, T2 mapping is a useful technique for the diagnosis and quantitation of diffuse myocardial edema.

Clinically suspected acute myopericarditis with cardiac tamponade associated with peripheral blood eosinophilia presenting in early pregnancy: a case report.

INTRODUCTION: The clinical presentation of eosinophilic myocarditis may vary from asymptomatic to the manifestation of severe symptoms, including cardiac tamponade and arrhythmias. In pregnant patients with this condition, drugs must be used cautiously up to approximately the 4th month of pregnancy because drug use should be limited during the period of fetal organogenesis. CASE PRESENTATION: A 30-year-old Asian woman at 14 weeks of pregnancy with progressive malaise was hospitalized. The electrocardiogram revealed ST elevation and low QRS voltage. Echocardiography revealed massive pericardial effusion and myocardial swelling. A laboratory examination revealed an increase in her white blood cell count, with a predominance of neutrophils. Pericardial drainage was performed for relief of the cardiac tamponade. The pericardial effusion revealed an abundance of eosinophils. Subsequently, the peripheral blood eosinophil count began to rise, and the patient was clinically diagnosed with eosinophilic myopericarditis. The patient's condition improved rapidly following the initiation of prednisolone treatment, and she finally delivered a full-term normal infant. CONCLUSIONS: A patient with clinically suspected myopericarditis in the early stage of pregnancy who improved rapidly with pericardial drainage and prednisolone therapy, and successfully delivered a normal full-term infant; the diagnosis was made in the early stage of the disease, based on the detection of an abundance of eosinophils in the pericardial effusion preceding the subsequent development of peripheral blood eosinophilia.

Differences in hemodynamic parameters and exercise capacity between patients with pulmonary arterial hypertension and chronic heart failure.

INTRODUCTION: Although pulmonary arterial hypertension (PAH) and chronic heart failure (CHF) lead to exercise limitation, their pathophysiology is different. Our objective was to evaluate, using right heart catheterization and cardiopulmonary exercise testing, the difference in hemodynamic parameters and exercise capacity between PAH and CHF, which have the same subjective symptoms. METHODS: We studied 20 PAH (mean pulmonary artery pressure: 36 ± 10 mmHg, all . 25 mmHg) and 20 CHF (ejection fraction: 35 ± 10%, all < 40%) patients who underwent both cardiopulmonary exercise testing and right heart catheterization. All patients were in New York Heart Association functional class II or III. RESULTS: Peak oxygen uptake (VO(2)) was lower for PAH patients than for CHF patients (11.7 ± 3.2 mL·kg(-1)·min(-1) vs 14.5 ± 4.6 mL·kg(-1)·min(-1), P = .03), while the slope of ventilation to carbon dioxide production ratio (VE/VCO(2)) was higher for PAH patients than for CHF patients (41.0 ± 12.7 vs 28.0 ± 9.0, P = .001), despite the similarity in their New York Heart Association functional class. Peak VO(2) and VE/VCO(2) correlated with cardiac index for both groups. An important finding was that peak VO(2) correlated with pulmonary vascular resistance for PAH patients (r = 20.46, P = .04) but not for CHF patients (r = 0.33, P = .15). Furthermore, peak VO(2) correlated with pulmonary capillary wedge pressure for CHF patients (r = 20.47, P = .03) but not for PAH patients (r = 0.17, P = .47), while the VE/VCO(2) slope correlated with pulmonary capillary wedge pressure (r = 0.67, P = .002) but not with pulmonary vascular resistance (r = 0.12, P = .63) for CHF patients. CONCLUSION: Peak VO(2) and VE/VCO(2) slope were worse for PAH patients than for CHF patients despite the similar subjective symptoms. This difference might be explained by an altered hemodynamic status.

Effect of left ventricular dyssynchrony on cardiac sympathetic activity in heart failure patients with wide QRS duration.

BACKGROUND: Dyssynchrony has various detrimental effects on cardiac function, but its effect on cardiac sympathetic activity is not fully understood. METHODS AND RESULTS: We studied 50 heart failure patients who underwent cardiac resynchronization therapy (CRT). Cardiac sympathetic activity was assessed by (123)I-metaiodobenzylguanidine ((123)I-MIBG) scintigraphy as the delayed heart-to-mediastinum ratio (H/M ratio). Echocardiography was performed before and 7 months after CRT, and response was defined as a ≥15% decrease in end-systolic volume. Dyssynchrony was determined by the time difference between the anteroseptal-to-posterior wall using speckle-tracking radial strain (≥130 ms predefined as significant). H/M ratio in patients with dyssynchrony was less than that in patients without dyssynchrony (1.62 ± 0.31 vs. 1.82 ± 0.36, P<0.05), even though ejection fraction was not significantly different (24 ± 6% vs. 25 ± 7%). Patients with dyssynchrony and H/M ratio ≥1.6 had a higher frequency of response to CRT (94%) and favorable long-term outcome over 3.0 years. In contrast, patients without dyssynchrony and H/M ratio <1.6 were more likely to show a lower frequency of response to CRT (0%) and unfavorable long-term outcome after CRT. CONCLUSIONS: Dyssynchrony is associated with cardiac sympathetic activity, and (123)I-MIBG scintigraphy may be valuable for predicting the response to CRT.